Effect of body weight gain on insulin sensitivity after retirement from exercise training

NASA Technical Reports Server (NTRS)

Dolkas, Constantine B.; Rodnick, Kenneth J.; Mondon, Carl E.

1990-01-01

The effect of the body-weight gain after retirement from an exercise-training program on the retained increase in insulin sensitivity elicited by the training was investigated in exercise-trained (ET) rats. Insulin sensitivity was assessed by oral glucose tolerance and insulin suppression tests immediately after training and during retirement. Results show that, compared with sedentary controls, exercise training enhanced insulin-induced glucose uptake, but the enhanced sensitivity was gradually lost with the end of running activity until after seven days of retirement, when it became equal to that of controls. This loss of enhanced sensitivity to insulin was associated with an accelerated gain in body weight beginning one day after the start of retirement. However, those animals that gained weight only at rates similar to those of control rats, retained their enhanced sensitivity to insulin.

Lack of stress responses to long-term effects of corticosterone in Caps2 knockout mice.

PubMed

Mishima, Yuriko; Shinoda, Yo; Sadakata, Tetsushi; Kojima, Masami; Wakana, Shigeharu; Furuichi, Teiichi

2015-03-10

Chronic stress is associated with anxiety and depressive disorders, and can cause weight gain. Ca(2+)-dependent activator protein for secretion 2 (CAPS2) is involved in insulin release. Caps2 knockout (KO) mice exhibit decreased body weight, reduced glucose-induced insulin release, and abnormal psychiatric behaviors. We chronically administered the stress hormone corticosterone (CORT), which induces anxiety/depressive-like behavior and normally increases plasma insulin levels, via the drinking water for 10 weeks, and we examined the stress response in KO mice. Chronic CORT exposure inhibited stress-induced serum CORT elevation in wild-type (WT) mice, but not in KO mice. Poor weight gain in CORT-treated animals was observed until week 6 in WT mice, but persisted for the entire duration of the experiment in KO mice, although there is no difference in drug*genotype interaction. Among KO mice, food consumption was unchanged, while water consumption was higher, over the duration of the experiment in CORT-treated animals, compared with untreated animals. Moreover, serum insulin and leptin levels were increased in CORT-treated WT mice, but not in KO mice. Lastly, both WT and KO mice displayed anxiety/depressive-like behavior after CORT administration. These results suggest that Caps2 KO mice have altered endocrine responses to CORT administration, while maintaining CORT-induced anxiety/depressive-like behavior.

Glycemic Control Over 5 Years in 4,900 People With Type 2 Diabetes

PubMed Central

Best, James D.; Drury, Paul L.; Davis, Timothy M.E.; Taskinen, Marja-Riitta; Kesäniemi, Y. Antero; Scott, Russell; Pardy, Christopher; Voysey, Merryn; Keech, Anthony C.

2012-01-01

OBJECTIVE Glycemic control in type 2 diabetes generally worsens over time, requiring intensification of therapy. The Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) trial provided the opportunity to observe glycemic control in a real-world setting. We assessed the adequacy of metformin, sulfonylureas, and insulin to maintain glycemic control and their effects on weight. RESEARCH DESIGN AND METHODS Diabetes control was measured at baseline and yearly for a median of 5 years in the 4,900 patients from the nonintervention arm of this study allocated to placebo. RESULTS Median HbA1c was 6.9% at baseline and increased by an average of 0.22% over 5 years (P < 0.001). Median weight was 86.3 kg at baseline and decreased by 0.4 kg over 5 years (P = 0.002). Baseline therapy was lifestyle measures only in 27%, oral agents without insulin in 59%, and insulin in 14% (7% also taking oral agents). Over 5 years, insulin use increased to 32% (21% also taking oral agents). Use of oral agents remained similar at 56%. Only 2% of patients at baseline and 4% after 5 years were taking oral agents other than metformin or sulfonylureas. Initiation of insulin therapy in 855 patients produced a sustained reduction of HbA1c from a median of 8.2 to 7.7%, with a weight gain of 4.6 kg over 5 years. CONCLUSIONS With intensification of traditional therapies, glycemic control deteriorated very little over 5 years in a large cohort of type 2 diabetes. However, the requirement for insulin therapy doubled, at the expense of significant weight gain and risk of hypoglycemia. PMID:22432105

Impaired Cardiolipin Biosynthesis Prevents Hepatic Steatosis and Diet-Induced Obesity

PubMed Central

Cole, Laura K.; Mejia, Edgard M.; Vandel, Marilyne; Sparagna, Genevieve C.; Claypool, Steven M.; Dyck-Chan, Laura; Klein, Julianne

2016-01-01

Mitochondria are the nexus of energy metabolism, and consequently their dysfunction has been implicated in the development of metabolic complications and progression to insulin resistance and type 2 diabetes. The unique tetra-acyl phospholipid cardiolipin (CL) is located in the inner mitochondrial membrane, where it maintains mitochondrial integrity. Here we show that knockdown of Tafazzin (TAZ kd), a CL transacylase, in mice results in protection against the development of obesity, insulin resistance, and hepatic steatosis. We determined that hypermetabolism protected TAZ kd mice from weight gain. Unexpectedly, the large reduction of CL in the heart and skeletal muscle of TAZ kd mice was not mirrored in the liver. As a result, TAZ kd mice exhibited normal hepatic mitochondrial supercomplex formation and elevated hepatic fatty acid oxidation. Collectively, these studies identify a key role for hepatic CL remodeling in regulating susceptibility to insulin resistance and as a novel therapeutic target for diet-induced obesity. PMID:27495222

Insulin and insulin-like growth factor-1 increased in preterm neonates following massage therapy.

PubMed

Field, Tiffany; Diego, Miguel; Hernandez-Reif, Maria; Dieter, John N I; Kumar, Adarsh M; Schanberg, Saul; Kuhn, Cynthia

2008-12-01

To determine if massage therapy increased serum insulin and insulin-like growth factor-1 (IGF-1) in preterm neonates. Forty-two preterm neonates who averaged 34.6 weeks (M = 29.5 wk gestational age; M birth weight = 1237 g) and were in the "grower" (step-down) nursery were randomly assigned to a massage therapy group (body stroking and passive limb movements for three, 15-minute periods per day for 5 days) or a control group that received the standard nursery care without massage therapy. On Days 1 and 5, the serum collected by clinical heelsticks was also assayed for insulin and IGF-1, and weight gain and kilocalories consumed were recorded daily. Despite similar formula intake, the massaged preterm neonates showed greater increases during the 5-day period in (1) weight gain; (2) serum levels of insulin; and (3) IGF-1. Increased weight gain was significantly correlated with insulin and IGF-1. Previous data suggested that preterm infant weight gain following massage therapy related to increased vagal activity, which suggests decreased stress and gastric motility, which may contribute to more efficient food absorption. The data from this study suggest for the first time that weight gain was also related to increased serum insulin and IGF-1 levels following massage therapy. Preterm infants who received massage therapy not only showed greater weight gain but also a greater increase in serum insulin and IGF-1 levels, suggesting that massage therapy might be prescribed for all growing neonates.

[Studies of diet management and insulin resistance in obese pregnant women].

PubMed

Takeda, S; Saitoh, M; Kinoshita, K; Sakamoto, S

1992-02-01

In an attempt to determine the principles of diet management in obese pregnant women, the association between maternal weight gain during pregnancy (Group I; weight reduction, Group II; +0-4 kg, Group III; +5-9 kg, Group IV; +10 kg-) and the incidence of the complications was investigated in 151 obese pregnant women. Studies on glucose tolerance and insulin binding to erythrocytes were also undertaken. 1) In Group I, the incidences of C/S, forceps delivery, prolonged labor and complication of PIH were lower than those of other groups. There were no heavy-for-dates and light-for-dates babies in Group I, differing from the other three groups. 2) Plasma levels of glucose and insulin were high in obese pregnant women on 75 g OGTT in the second trimester. The binding sites of insulin to erythrocytes were significantly decreased in obese pregnant women. In conclusion, the risks of pregnancy complicated by obesity were high. Insulin resistance was a characteristic of obese pregnant women. The results of this study suggested that the nutritional requirements for very obese pregnant women should be restricted to maintaining the same weight or losing weight during the course of pregnancy to minimize maternal and perinatal risks.

Reversal of diet-induced obesity and insulin resistance by inducible genetic ablation of GRK2

PubMed Central

Vila-Bedmar, Rocio; Cruces-Sande, Marta; Lucas, Elisa; Willemen, Hanneke L.D.M.; Heijnen, Cobi J.; Kavelaars, Annemieke; Mayor, Federico; Murga, Cristina

2015-01-01

Insulin resistance is a common feature of obesity and predisposes individuals to various prevalent pathological conditions. G protein-coupled receptor kinase 2 (GRK2) integrates several signal transduction pathways and is emerging as a physiologically relevant inhibitor of insulin signaling. GRK2 abundanceis increased in humans with metabolic syndrome and in different murine models of insulin resistance. To support GRK2 as a potential drug target in type 2 diabetes and obesity, we investigated whether lowering GRK2 abundance reversed an ongoing systemic insulin-resistant phenotype, using a mouse model of tamoxifen-induced GRK2 ablation after high fat diet-dependent obesity and insulin resistance. Tamoxifen-triggered GRK2 deletion impeded further body weight gain, normalized fa sting glycemia, improved glucose tolerance and was associated with preserved insulin sensitivity in skeletal muscle and liver, thereby maintaining whole body glucose homeostasis. Moreover, when continued to be fed a high fat diet, these animals displayed reduced fat mass and smaller adipocytes, were resistant to the development of liver steatosis, and showed reduced expression of pro-inflammatory markers in the liver. Our results indicate that GRK2 acts as a hub to control metabolic functions in different tissues, which is key to controlling insulin resistance development in vivo. These data suggest that inhibiting GRK2 could reverse an established insulin-resistant and obese phenotype, thereby putting forward this enzyme as a potential therapeutic target linking glucose homeostasis and regulation of adiposity. PMID:26198359

Age and body weight effects on glucose and insulin tolerance in colony cats maintained since weaning on high dietary carbohydrate.

PubMed

Backus, R C; Cave, N J; Ganjam, V K; Turner, J B M; Biourge, V C

2010-12-01

High dietary carbohydrate is suggested to promote development of diabetes mellitus in cats. Glucose tolerance, insulin sensitivity, and insulin secretion were assessed in young [0.8-2.3 (median = 1.1) years, n = 13] and mature [4.0-7.0 (median 5.8) years, n = 12] sexually intact females of a large (n ≅ 700) feline colony in which only dry-type diets (35% metabolizable energy as carbohydrate) were fed from weaning. Insulin sensitivity was assessed from the 'late-phase' (60-120 min) plasma insulin response of intravenous glucose tolerance tests (IVGTTs) and from fractional change in glycaemia from baseline 15 min after an insulin bolus (0.1 U/kg, i.v.). Insulin secretion was assessed from the 'early-phase' (0-15 min) plasma insulin response of IVGTTs. Compared to the young cats, the mature cats had greater body weights [2.3-3.8 (median = 2.9) vs. 3.0-6.3 (median = 4.0) kg, p < 0.01], greater late-phase insulin responses (p < 0.05), lower insulin-induced glycaemic changes (p = 0.06), lower early-phase insulin responses (p < 0.05), and non-significantly different rates of glucose disposal. The late-phase insulin response was correlated with body weight and age (p < 0.05). When group assignments were balanced for body weight, the age-group differences and correlations became non-significant. The findings indicate that body weight gain is more likely than dry-type diets to induce the pre-diabetic conditions of insulin resistance and secretion dysfunction. © 2010 The Authors. Journal of Animal Physiology and Animal Nutrition © 2010 Blackwell Verlag GmbH.

Cost-effectiveness of insulin detemir compared with NPH insulin in people with type 2 diabetes in Denmark, Finland, Norway, and Sweden.

PubMed

Ridderstråle, Martin; Jensen, Marie Markert; Gjesing, Rasmus Prior; Niskanen, Leo

2013-01-01

To assess the cost-effectiveness of insulin detemir compared with Neutral Protamine Hagedorn (NPH) insulin when initiating insulin treatment in people with type 2 diabetes mellitus (T2DM) in Denmark, Finland, Norway, and Sweden. Efficacy and safety data were derived from a 20-week multi-centre randomized controlled head-to-head clinical trial comparing insulin detemir and NPH insulin in insulin naïve people with T2DM, and short-term (1-year) cost effectiveness analyses were performed. As no significant differences in HbA1c were observed between the two treatment arms, the model was based on significant differences in favour of insulin detemir in frequency of hypoglycaemia (Rate-Ratio = 0.52; CI = 0.44-0.61) and weight gain (Δ = 0.9 kg). Model outcomes were measured in Quality Adjusted Life Years (QALYs) using published utility estimates. Acquisition costs for insulin and direct healthcare costs associated with non-severe hypoglycaemic events were obtained from National Health Service public sources. One-way and probabilistic sensitivity analyses were performed. Based on lower incidence of non-severe hypoglycaemic events and less weight gain, the QALY gain from initiating treatment with insulin detemir compared with NPH insulin was 0.01 per patient per year. Incremental cost-effectiveness ratios for the individual countries were: Denmark, Danish Kroner 170,852 (€22,933); Finland, €28,349; Norway, Norwegian Kroner 169,789 (€21,768); and Sweden, Swedish Krona 226,622 (€25,097) per QALY gained. Possible limitations of the study are that data on hypoglycaemia and relative weight benefits from a clinical trial were combined with hypoglycaemia incidence data from observational studies. These populations may have slightly different patient characteristics. The lower risk of non-severe hypoglycaemia and less weight gain associated with using insulin detemir compared with NPH insulin when initiating insulin treatment in insulin naïve patients with type 2 diabetes provide economic benefits in the short-term. Based on cost/QALY threshold values, this represents good value for money in the Nordic countries. Using a short-term modelling approach may be conservative, as reduced frequency of hypoglycaemia and less weight gain may also have positive long-term health-related implications.

The role of Toujeo®, insulin glargine U-300, in the treatment of diabetes mellitus.

PubMed

Brown, Meagan A; Davis, Courtney S; Fleming, Laurie W; Fleming, Joshua W

2016-09-01

The purpose of this article is to educate nurse practitioners about the role of Toujeo®, insulin glargine U-300 (Gla-300), which is a new option for the treatment of diabetes mellitus. A comprehensive literature search was conducted using MEDLINE with the key terms: insulin glargine 300, Toujeo, Gla-300, and EDITION for clinical trial data. Other resources included package inserts, drug information websites, and the World Health Organization (WHO). Gla-300 appears to be a safe and effective option for basal insulin therapy. In clinical trials, it was shown to be equally efficacious as Gla-100 with fewer episodes of hypoglycemia and slightly less weight gain, and subjects receiving Gla-300 required approximately 10 units more basal insulin to obtain the same hemoglobin A1c (HbA1c) as subjects receiving Gla-100. This new basal therapy option represents a potential advantage for patients who require higher doses of insulin because of the higher concentration of Gla-300. The lower incidence of hypoglycemia and more predictable pharmacokinetics could offer a significant therapeutic benefit in difficult-to-control patients with diabetes mellitus. The biggest disadvantage of this product is the slightly higher insulin dosage that is required to improve and/or maintain patients' HbA1c. ©2016 American Association of Nurse Practitioners.

Effects of two commercially available feline diets on glucose and insulin concentrations, insulin sensitivity and energetic efficiency of weight gain.

PubMed

Coradini, M; Rand, J S; Morton, J M; Rawlings, J M

2011-10-01

A low-carbohydrate, high-protein (LCHP) diet is often recommended for the prevention and management of diabetes in cats; however, the effect of macronutrient composition on insulin sensitivity and energetic efficiency for weight gain is not known. The present study compared the effect in adult cats (n 32) of feeding a LCHP (23 and 47 % metabolisable energy (ME)) and a high-carbohydrate, low-protein (HCLP) diet (51 and 21 % ME) on fasting and postprandial glucose and insulin concentrations, and on insulin sensitivity. Tests were done in the 4th week of maintenance feeding and after 8 weeks of ad libitum feeding, when weight gain and energetic efficiency of each diet were also measured. When fed at maintenance energy, the HCLP diet resulted in higher postprandial glucose and insulin concentrations. When fed ad libitum, the LCHP diet resulted in greater weight gain (P < 0.01), and was associated with higher energetic efficiency. Overweight cats eating the LCHP diet had similar postprandial glucose concentrations to lean cats eating the HCLP diet. Insulin sensitivity was not different between the diets when cats were lean or overweight, but glucose effectiveness was higher after weight gain in cats fed the HCLP diet. According to the present results, LCHP diets fed at maintenance requirements might benefit cats with multiple risk factors for developing diabetes. However, ad libitum feeding of LCHP diets is not recommended as they have higher energetic efficiency and result in greater weight gain.

The origins of western obesity: a role for animal protein?

PubMed

McCarty, M F

2000-03-01

A reduced propensity to oxidize fat, as indicated by a relatively high fasting respiratory quotient, is a major risk factor for weight gain. Increased insulin secretion works in various ways to impede fat oxidation and promote fat storage. The substantial 'spontaneous' weight loss often seen with very-low-fat dietary regimens may reflect not only a reduced rate of fat ingestion, but also an improved insulin sensitivity of skeletal muscle that down-regulates insulin secretion. Reduction of diurnal insulin secretion may also play a role in the fat loss often achieved with exercise training, low-glycemic-index diets, supplementation with soluble fiber or chromium, low-carbohydrate regimens, and biguanide therapy. The exceptional leanness of vegan cultures may reflect an additional factor - the absence of animal protein. Although dietary protein by itself provokes relatively little insulin release, it can markedly potentiate the insulin response to co-ingested carbohydrate; Western meals typically unite starchy foods with an animal protein-based main course. Thus, postprandial insulin secretion may be reduced by either avoiding animal protein, or segregating it in low-carbohydrate meals; the latter practice is a feature of fad diets stressing 'food combining'. Vegan diets tend to be relatively low in protein, legume protein may be slowly absorbed, and, as compared to animal protein, isolated soy protein provokes a greater release of glucagon, an enhancer of fat oxidation. The low insulin response to rice may mirror its low protein content. Minimizing diurnal insulin secretion in the context of a low fat intake may represent an effective strategy for achieving and maintaining leanness. Copyright 2000 Harcourt Publishers Ltd.

Sweet taste of saccharin induces weight gain without increasing caloric intake, not related to insulin-resistance in Wistar rats.

PubMed

Foletto, Kelly Carraro; Melo Batista, Bruna Aparecida; Neves, Alice Magagnin; de Matos Feijó, Fernanda; Ballard, Cíntia Reis; Marques Ribeiro, Maria Flávia; Bertoluci, Marcello Casaccia

2016-01-01

In a previous study, we showed that saccharin can induce weight gain when compared with sucrose in Wistar rats despite similar total caloric intake. We now question whether it could be due to the sweet taste of saccharin per se. We also aimed to address if this weight gain is associated with insulin-resistance and to increases in gut peptides such as leptin and PYY in the fasting state. In a 14 week experiment, 16 male Wistar rats received either saccharin-sweetened yogurt or non-sweetened yogurt daily in addition to chow and water ad lib. We measured daily food intake and weight gain weekly. At the end of the experiment, we evaluated fasting leptin, glucose, insulin, PYY and determined insulin resistance through HOMA-IR. Cumulative weight gain and food intake were evaluated through linear mixed models. Results showed that saccharin induced greater weight gain when compared with non-sweetened control (p = 0.027) despite a similar total caloric intake. There were no differences in HOMA-IR, fasting leptin or PYY levels between groups. We conclude that saccharin sweet taste can induce mild weight gain in Wistar rats without increasing total caloric intake. This weight gain was not related with insulin-resistance nor changes in fasting leptin or PYY in Wistar rats. Copyright © 2015 Elsevier Ltd. All rights reserved.

Hyperleptinaemia rather than fasting hyperinsulinaemia is associated with obesity following hypothalamic damage in children.

PubMed

Shaikh, M Guftar; Grundy, Richard G; Kirk, Jeremy M W

2008-12-01

Obesity following hypothalamic damage is often severe and resistant to lifestyle changes. Disruption of hypothalamic feedback mechanisms that maintain energy homeostasis may be responsible for this intractable obesity. Adipocytokines including insulin and leptin are also known to be important regulators of appetite and weight. To investigate the role of insulin, leptin, adiponectin and resistin in the aetiology of hypothalamic obesity (HO). This was a cross-sectional study of three groups of children, those with HO, congenital hypopituitarism (CH) and simple obesity (SO). A total of 69 children (HO=28, CH=18, SO=23) had leptin, resistin, adiponectin and insulin measured. Although fasting hyperinsulinaemia and insulin resistance were demonstrated, no differences in insulin or insulin resistance were seen between the groups. The HO group, however, had higher levels of leptin, adiponectin and resistin, which persisted even after adjusting for fat mass, compared with the other groups (P<0.05). No differences in fasting hyperinsulinaemia or insulin resistance were seen between the groups; however, leptin levels are elevated, even after adjusting for fat mass, suggesting that an element of leptin resistance is associated with HO. This is consistent with the inability of leptin to act on the hypothalamus, either due to transport across the blood-brain barrier or dysfunctional receptors. The lack of response to leptin may be more important in the development of obesity in these individuals, and the fasting hyperinsulinaemia is a result of the increased adipose tissue rather than the cause of the weight gain.

Weight gain in insulin-treated patients by body mass index category at treatment initiation: new evidence from real-world data in patients with type 2 diabetes.

PubMed

Paul, S K; Shaw, J E; Montvida, O; Klein, K

2016-12-01

To evaluate, in patients with type 2 diabetes (T2DM) treated with insulin, the extent of weight gain over 2 years of insulin treatment, and the dynamics of weight gain in relation to glycaemic achievements over time according to adiposity levels at insulin initiation. Patients with T2DM (n = 155 917), who commenced insulin therapy and continued it for at least 6 months, were selected from a large database of electronic medical records in the USA. Longitudinal changes in body weight and glycated haemoglobin (HbA1c) according to body mass index (BMI) category were estimated. Patients had a mean age of 59 years, a mean HbA1c level of 9.5%, and a mean BMI of 35 kg/m 2 at insulin initiation. The HbA1c levels at insulin initiation were significantly lower (9.2-9.4%) in the obese patients than in patients with normal body weight (10.0%); however, the proportions of patients with HbA1c >7.5% or >8.0% were similar across the BMI categories. The adjusted weight gain fell progressively with increasing baseline BMI category over 6, 12 and 24 months (p < .01). The adjusted changes in HbA1c were similar across BMI categories. A 1% decrease in HbA1c was associated with progressively less weight gain as pretreatment BMI rose, ranging from a 1.24 kg gain in those with a BMI <25 kg/m 2 to a 0.32 kg loss in those with a BMI > 40 kg/m 2 . During 24 months of insulin treatment, obese patients gained significantly less body weight than normal-weight and overweight patients, while achieving clinically similar glycaemic benefits. These data provide reassurance with regard to the use of insulin in obese patients. © 2016 John Wiley & Sons Ltd.

Sucrose diet induced enzymatic and hormonal responses affecting carbohydrate, lipid and energy metabolism in two species differing in insulin availability: spiny and ob/ob mice.

PubMed

Shafrir, E; Trostler, N

1984-01-01

The low-insulin responding spiny mice (Acomys cahirinus), maintained on a 50% sucrose diet vs isocaloric regular diet, responded with an impressive increase in the activity of hepatic enzymes of glycolysis and lipogenesis and in hyperlipidemia. There was no hyperinsulinemia or hyperglycemia and spiny mice did not gain weight on sucrose due to loss of adipose tissue. Serum T3 levels rose 1.8 fold and the activity of the hepatic mitochondrial FAD-glycerol-3-phosphate oxidase became induced 2.6 fold representing the enhancement of multiple, T3-dependent, energy-consuming metabolic cycles. An increased TG lipolysis in adipose tissue was also observed. C57BL/6J ob/ob mice were markedly hyperinsulinemic and gained weight on sucrose almost as much as those on regular diet, without changes in serum glucose or insulin. Serum triglyceride level decreased, whereas liver triglycerides accumulated markedly. The extent of the increase in hepatic enzyme activities related to lipogenesis was much lower both in the ob/ob mice and their lean siblings, than in spiny mice, but the basal enzyme activities in ob/ob mice were remarkably elevated. Serum T3 level was also elevated already on the regular diet and rose only slightly on sucrose. Basal glycerol phosphate oxidase activity in ob/ob mice exceeded that in spiny mice and rose only marginally on sucrose. Adipose tissue lipolysis was not increased. Thus, sucrose diet by enhancing the T3 production appeared to activate protective mechanism against weight gain in normoinsulinemic spiny mice, whereas the full expression of these mechanisms appeared to be precluded by the hyperinsulinemia of ob/ob mice.(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of body weight and type of chow on the sensitivity of rats to the behavioral effects of the direct-acting dopamine receptor agonist quinpirole

PubMed Central

Baladi, Michelle G; Newman, Amy H; France, Charles P

2013-01-01

Rationale Amount and type of food can alter dopamine systems and sensitivity to drugs acting on those systems. Objectives This study examined whether changes in body weight, food type, or both body weight and food type contribute to these effects. Methods Rats had free or restricted access (increasing, decreasing, or maintaining body weight) to standard (5.7% fat) or high fat (34.3%) chow. Results In rats gaining weight with restricted or free access to high fat chow, both limbs of the quinpirole yawning dose-response curve (0.0032–0.32 mg/kg) shifted leftward compared with rats eating standard chow. Restricting access to standard or high fat chow (maintaining or decreasing body weight) decreased or eliminated quinpirole-induced yawning; within one week of resuming free feeding, sensitivity to quinpirole was restored, although the descending limb of the dose-response curve was shifted leftward in rats eating high fat chow. These are not likely pharmacokinetic differences because quinpirole-induced hypothermia was not different among groups. PG01037 and L-741,626 antagonized the ascending and descending limbs of the quinpirole dose-response curve in rats eating high fat chow, indicating D3 and D2 receptor mediation, respectively. Rats eating high fat chow also developed insulin resistance. Conclusions These results show that amount and type of chow alter sensitivity to a direct-acting dopamine receptor agonist with the impact of each factor depending on whether body weight increases, decreases, or is maintained. These data demonstrate that feeding conditions, perhaps related to insulin and insulin sensitivity, profoundly impact the actions of drugs acting on dopamine systems. PMID:21544521

Influence of body weight and type of chow on the sensitivity of rats to the behavioral effects of the direct-acting dopamine-receptor agonist quinpirole.

PubMed

Baladi, Michelle G; Newman, Amy H; France, Charles P

2011-10-01

Amount and type of food can alter dopamine systems and sensitivity to drugs acting on those systems. This study examined whether changes in body weight, food type, or both body weight and food type contribute to these effects. Rats had free or restricted access (increasing, decreasing, or maintaining body weight) to standard (5.7% fat) or high-fat (34.3%) chow. In rats gaining weight with restricted or free access to high-fat chow, both limbs of the quinpirole yawning dose-response curve (0.0032-0.32 mg/kg) shifted leftward compared with rats eating standard chow. Restricting access to standard or high-fat chow (maintaining or decreasing body weight) decreased or eliminated quinpirole-induced yawning; within 1 week of resuming free feeding, sensitivity to quinpirole was restored, although the descending limb of the dose-response curve was shifted leftward in rats eating high-fat chow. These are not likely pharmacokinetic differences because quinpirole-induced hypothermia was not different among groups. PG01037 and L-741,626 antagonized the ascending and descending limbs of the quinpirole dose-response curve in rats eating high-fat chow, indicating D3 and D2 receptor mediation, respectively. Rats eating high-fat chow also developed insulin resistance. These results show that amount and type of chow alter sensitivity to a direct-acting dopamine-receptor agonist with the impact of each factor depending on whether body weight increases, decreases, or is maintained. These data demonstrate that feeding conditions, perhaps related to insulin and insulin sensitivity, profoundly impact the actions of drugs acting on dopamine systems.

Combination Therapy With Exenatide Plus Pioglitazone Versus Basal/Bolus Insulin in Patients With Poorly Controlled Type 2 Diabetes on Sulfonylurea Plus Metformin: The Qatar Study

PubMed Central

Abdul-Ghani, Muhammad; Migahid, Osama; Megahed, Ayman; Adams, John; Triplitt, Curtis; DeFronzo, Ralph A.; Zirie, Mahmoud; Jayyousi, Amin

2017-01-01

OBJECTIVE The Qatar Study was designed to examine the efficacy of combination therapy with exenatide plus pioglitazone versus basal/bolus insulin in patients with long-standing poorly controlled type 2 diabetes mellitus (T2DM) on metformin plus a sulfonylurea. RESEARCH DESIGN AND METHODS The study randomized 231 patients with poorly controlled (HbA1c >7.5%, 58 mmol/mol) T2DM on a sulfonylurea plus metformin to receive 1) pioglitazone plus weekly exenatide (combination therapy) or 2) basal plus prandial insulin (insulin therapy) to maintain HbA1c <7.0% (53 mmol/mol). RESULTS After a mean follow-up of 12 months, combination therapy caused a robust decrease in HbA1c from 10.0 ± 0.6% (86 ± 5.2 mmol/mol) at baseline to 6.1 ± 0.1% (43 ± 0.7 mmol/mol) compared with 7.1 ± 0.1% (54 ± 0.8 mmol/mol) in subjects receiving insulin therapy. Combination therapy was effective in lowering the HbA1c independent of sex, ethnicity, BMI, or baseline HbA1c. Subjects in the insulin therapy group experienced significantly greater weight gain and a threefold higher rate of hypoglycemia than patients in the combination therapy group. CONCLUSIONS Combination exenatide/pioglitazone therapy is a very effective and safe therapeutic option in patients with long-standing poorly controlled T2DM on metformin plus a sulfonylurea. PMID:28096223

Fenofibrate Decreases Insulin Clearance and Insulin Secretion to Maintain Insulin Sensitivity*

PubMed Central

Ramakrishnan, Sadeesh K.; Russo, Lucia; Ghanem, Simona S.; Patel, Payal R.; Oyarce, Ana Maria; Heinrich, Garrett; Najjar, Sonia M.

2016-01-01

High fat diet reduces the expression of CEACAM1 (carcinoembryonic antigen-related cell adhesion molecule 1), a transmembrane glycoprotein that promotes insulin clearance and down-regulates fatty acid synthase activity in the liver upon its phosphorylation by the insulin receptor. Because peroxisome proliferator-activated receptor α (PPARα) transcriptionally suppresses CEACAM1 expression, we herein examined whether high fat down-regulates CEACAM1 expression in a PPARα-dependent mechanism. By activating PPARα, the lipid-lowering drug fenofibrate reverses dyslipidemia and improves insulin sensitivity in type 2 diabetes in part by promoting fatty acid oxidation. Despite reducing glucose-stimulated insulin secretion, fenofibrate treatment does not result in insulin insufficiency. To examine whether this is mediated by a parallel decrease in CEACAM1-dependent hepatic insulin clearance pathways, we fed wild-type and Pparα−/− null mice a high fat diet supplemented with either fenofibrate or Wy14643, a selective PPARα agonist, and examined their effect on insulin metabolism and action. We demonstrated that the decrease in insulin secretion by fenofibrate and Wy14643 is accompanied by reduction in insulin clearance in wild-type but not Pparα−/− mice, thereby maintaining normoinsulinemia and insulin sensitivity despite continuous high fat intake. Intact insulin secretion in L-CC1 mice with protected hepatic insulin clearance and CEACAM1 levels provides in vivo evidence that insulin secretion responds to changes in insulin clearance to maintain physiologic insulin and glucose homeostasis. These results also emphasize the relevant role of hepatic insulin extraction in regulating insulin sensitivity. PMID:27662905

Novel Use of Glucagon in a Closed-Loop System for Prevention of Hypoglycemia in Type 1 Diabetes

PubMed Central

Castle, Jessica R.; Engle, Julia M.; Youssef, Joseph El; Massoud, Ryan G.; Yuen, Kevin C.J.; Kagan, Ryland; Ward, W. Kenneth

2010-01-01

OBJECTIVE To minimize hypoglycemia in subjects with type 1 diabetes by automated glucagon delivery in a closed-loop insulin delivery system. RESEARCH DESIGN AND METHODS Adult subjects with type 1 diabetes underwent one closed-loop study with insulin plus placebo and one study with insulin plus glucagon, given at times of impending hypoglycemia. Seven subjects received glucagon using high-gain parameters, and six subjects received glucagon in a more prolonged manner using low-gain parameters. Blood glucose levels were measured every 10 min and insulin and glucagon infusions were adjusted every 5 min. All subjects received a portion of their usual premeal insulin after meal announcement. RESULTS Automated glucagon plus insulin delivery, compared with placebo plus insulin, significantly reduced time spent in the hypoglycemic range (15 ± 6 vs. 40 ± 10 min/day, P = 0.04). Compared with placebo, high-gain glucagon delivery reduced the frequency of hypoglycemic events (1.0 ± 0.6 vs. 2.1 ± 0.6 events/day, P = 0.01) and the need for carbohydrate treatment (1.4 ± 0.8 vs. 4.0 ± 1.4 treatments/day, P = 0.01). Glucagon given with low-gain parameters did not significantly reduce hypoglycemic event frequency (P = NS) but did reduce frequency of carbohydrate treatment (P = 0.05). CONCLUSIONS During closed-loop treatment in subjects with type 1 diabetes, high-gain pulses of glucagon decreased the frequency of hypoglycemia. Larger and longer-term studies will be required to assess the effect of ongoing glucagon treatment on overall glycemic control. PMID:20332355

Glucosamine enhances body weight gain and reduces insulin response in mice fed chow diet but mitigates obesity, insulin resistance and impaired glucose tolerance in mice high-fat diet.

PubMed

Hwang, Ji-Sun; Park, Ji-Won; Nam, Moon-Suk; Cho, Hyeongjin; Han, Inn-Oc

2015-03-01

This study investigated the potential of glucosamine (GlcN) to affect body weight gain and insulin sensitivity in mice normal and at risk for developing diabetes. Male C57BL/6J mice were fed either chow diet (CD) or a high fat diet (HFD) and the half of mice from CD and HFD provided with a solution of 10% (w/v) GlcN. Total cholesterol and nonesterified free fatty acid levels were determined. Glucose tolerance test and insulin tolerance test were performed. HepG2 human hepatoma cells or differentiated 3T3-L1 adipocytes were stimulated with insulin under normal (5 mM) or high glucose (25 mM) conditions. Effect of GlcN on 2-deoxyglucose (2-DG) uptake was determined. JNK and Akt phosphorylation and nucleocytoplasmic protein O-GlcNAcylation were assayed by Western blotting. GlcN administration stimulated body weight gain (6.58±0.82 g vs. 11.1±0.42 g), increased white adipose tissue fat mass (percentage of bodyweight, 3.7±0.32 g vs. 5.61±0.34 g), and impaired the insulin response in livers of mice fed CD. However, GlcN treatment in mice fed HFD led to reduction of body weight gain (18.02±0.66 g vs. 16.22±0.96 g) and liver weight (2.27±0.1 vs. 1.85±0.12 g). Furthermore, obesity-induced insulin resistance and impaired Akt insulin signaling in the liver were alleviated by GlcN administration. GlcN inhibited the insulin response under low (5 mM) glucose conditions, whereas it restored the insulin response for Akt phosphorylation under high (25 mM) glucose conditions in HepG2 and 3T3-L1 cells. Uptake of 2-DG increased upon GlcN treatment under 5 mM glucose compared to control, whereas insulin-stimulated 2-DG uptake decreased under 5 mM and increased under 25 mM glucose in differentiated 3T3-L1 cells. Our results show that GlcN increased body weight gain and reduced the insulin response for glucose maintenance when fed to normal CD mice, whereas it alleviated body weight gain and insulin resistance in HFD mice. Therefore, the current data support the integrative function of the HBP reflecting the nutrient status of lipids or glucose and further implicate the importance of the pathway in insulin signaling for the regulation of metabolism. Copyright © 2015 Elsevier Inc. All rights reserved.

Deletion of the alpha-arrestin protein Txnip in mice promotes adiposity and adipogenesis while preserving insulin sensitivity.

PubMed

Chutkow, William A; Birkenfeld, Andreas L; Brown, Jonathan D; Lee, Hui-Young; Frederick, David W; Yoshioka, Jun; Patwari, Parth; Kursawe, Romy; Cushman, Samuel W; Plutzky, Jorge; Shulman, Gerald I; Samuel, Varman T; Lee, Richard T

2010-06-01

Thioredoxin interacting protein (Txnip), a regulator of cellular oxidative stress, is induced by hyperglycemia and inhibits glucose uptake into fat and muscle, suggesting a role for Txnip in type 2 diabetes pathogenesis. Here, we tested the hypothesis that Txnip-null (knockout) mice are protected from insulin resistance induced by a high-fat diet. Txnip gene-deleted (knockout) mice and age-matched wild-type littermate control mice were maintained on a standard chow diet or subjected to 4 weeks of high-fat feeding. Mice were assessed for body composition, fat development, energy balance, and insulin responsiveness. Adipogenesis was measured from ex vivo fat preparations, and in mouse embryonic fibroblasts (MEFs) and 3T3-L1 preadipocytes after forced manipulation of Txnip expression. Txnip knockout mice gained significantly more adipose mass than controls due to a primary increase in both calorie consumption and adipogenesis. Despite increased fat mass, Txnip knockout mice were markedly more insulin sensitive than controls, and augmented glucose transport was identified in both adipose and skeletal muscle. RNA interference gene-silenced preadipocytes and Txnip(-/-) MEFs were markedly adipogenic, whereas Txnip overexpression impaired adipocyte differentiation. As increased adipogenesis and insulin sensitivity suggested aspects of augmented peroxisome proliferator-activated receptor-gamma (PPARgamma) response, we investigated Txnip's regulation of PPARgamma function; manipulation of Txnip expression directly regulated PPARgamma expression and activity. Txnip deletion promotes adiposity in the face of high-fat caloric excess; however, loss of this alpha-arrestin protein simultaneously enhances insulin responsiveness in fat and skeletal muscle, revealing Txnip as a novel mediator of insulin resistance and a regulator of adipogenesis.

Insulin sensitivity and metabolic flexibility following exercise training among different obese insulin-resistant phenotypes.

PubMed

Malin, Steven K; Haus, Jacob M; Solomon, Thomas P J; Blaszczak, Alecia; Kashyap, Sangeeta R; Kirwan, John P

2013-11-15

Impaired fasting glucose (IFG) blunts the reversal of impaired glucose tolerance (IGT) after exercise training. Metabolic inflexibility has been implicated in the etiology of insulin resistance; however, the efficacy of exercise on peripheral and hepatic insulin sensitivity or substrate utilization in adults with IFG, IGT, or IFG + IGT is unknown. Twenty-four older (66.7 ± 0.8 yr) obese (34.2 ± 0.9 kg/m(2)) adults were categorized as IFG (n = 8), IGT (n = 8), or IFG + IGT (n = 8) according to a 75-g oral glucose tolerance test (OGTT). Subjects underwent 12-wk of exercise (60 min/day for 5 days/wk at ∼85% HRmax) and were instructed to maintain a eucaloric diet. A euglycemic hyperinsulinemic clamp (40 mU·m(2)·min(-1)) with [6,6-(2)H]glucose was used to determine peripheral and hepatic insulin sensitivity. Nonoxidative glucose disposal and metabolic flexibility [insulin-stimulated respiratory quotient (RQ) minus fasting RQ] were also assessed. Glucose incremental area under the curve (iAUCOGTT) was calculated from the OGTT. Exercise increased clamp-derived peripheral and hepatic insulin sensitivity more in adults with IFG or IGT alone than with IFG + IGT (P < 0.05). Exercise reduced glucose iAUCOGTT in IGT only (P < 0.05), and the decrease in glucose iAUCOGTT was inversely correlated with the increase in peripheral but not hepatic insulin sensitivity (P < 0.01). Increased clamp-derived peripheral insulin sensitivity was also correlated with enhanced metabolic flexibility, reduced fasting RQ, and higher nonoxidative glucose disposal (P < 0.05). Adults with IFG + IGT had smaller gains in clamp-derived peripheral insulin sensitivity and metabolic flexibility, which was related to blunted improvements in postprandial glucose. Additional work is required to assess the molecular mechanism(s) by which chronic hyperglycemia modifies insulin sensitivity following exercise training.

Insulin resistance and its association with catch-up growth in Chinese children born small for gestational age.

PubMed

Liu, Chunhua; Wu, Baiyan; Lin, Niyang; Fang, Xiaoyi

2017-01-01

To assess insulin resistance and β-cell function from birth to age 4 years and to examine their associations with catch-up growth (CUG) in Chinese small-for-gestational-age (SGA) children. Weight and height were measured yearly from birth to age 4 years, and transformed into age- and gender-adjusted SD scores. Fasting serum insulin and glucose were measured, and fasting insulin resistance and β-cell function were estimated using the homeostasis model assessment (HOMA). The mean HOMA-IR of the SGA group was significantly lower than that of the appropriate-for-gestational-age (AGA) group at ages 2 and 3 years old, and the mean HOMA% of the SGA group was significantly lower than that of the AGA group at age 4 years old. At 4 years of age, HOMA for insulin resistance was positively correlated with the height gain and SD of height gain between 0 and 5 months, and HOMA% was positively correlated with the weight gain and SD of weight gain between 6 and 12 months in SGA children. SGA children with CUG show a greater propensity to develop insulin resistance than AGA children between ages 2 and 4 years old. HOMA parameters are related to CUG in the first year of life. © 2016 The Obesity Society.

Treatment Strategy for Type 2 Diabetes with Obesity: Focus on Glucagon-like Peptide-1 Receptor Agonists.

PubMed

Ji, Qiuhe

2017-06-01

The progressive nature of type 2 diabetes mellitus (T2DM) calls for step-wise intensification of therapy for maintaining normal glycemic levels and lowering cardiovascular (CV) risk. Because obesity is a prominent risk factor and comorbidity of T2DM, it further elevates the CV risk in T2DM. Therefore, it is vital to manage weight, obesity, and glycemic parameters for effective T2DM management. Few oral antidiabetic drugs (sulfonylureas and thiazolidinediones) and insulin are not suitable for obese patients with T2DM because these drugs cause weight gain. The present review discusses the place of glucagon-like peptide-1 receptor agonists (GLP-1RAs) in the treatment of obese patients with T2DM and the significance of these drugs in the prevention of future CV risk in patients with T2DM. A literature search of PubMed and EMBASE was conducted by using the search terms T2DM, GLP-1RAs, obesity, and cardiovascular complication. Randomized controlled trials measuring the effect of GLP-1RAs versus that of placebo on CV outcomes were included in the review. GLP-1RAs have emerged as a therapeutic alternative; these drugs exert their actions by providing glycemic control, improving insulin resistance and ö̇-cell function, and reducing weight. The risk of hypoglycemia with GLP-1RAs is minimal; however, GLP-1RAs are associated with gastrointestinal adverse events and raise concerns regarding pancreatitis. Combining GLP-1RAs with insulin analogues results in higher efficacy, a lowered insulin dose, and reduced insulin-related hypoglycemia and weight gain. Longer acting GLP-1RAs are also associated with improvement in medication adherence. Improvement in CV risk factors such as blood pressure and lipid profile further increases their usability for improving CV outcomes. Overall, the properties of GLP-1RAs make them suitable for combination with oral antidiabetic drugs in the early stages of T2DM and with insulins in the later stages for optimizing comprehensive management of the disease. Copyright © 2017 Elsevier HS Journals, Inc. All rights reserved.

Metabolic profiling in Prader-Willi syndrome and nonsyndromic obesity: sex differences and the role of growth hormone.

PubMed

Irizarry, Krystal A; Bain, James; Butler, Merlin G; Ilkayeva, Olga; Muehlbauer, Michael; Haqq, Andrea M; Freemark, Michael

2015-12-01

To identify metabolic factors controlling appetite and insulin sensitivity in PWS and assess effects of GH treatment. We compared amino acids, fatty acids and acylcarnitines in GH-treated and untreated PWS children and obese and lean controls to identify biomarkers associated with ghrelin, peptide YY and markers of insulin sensitivity (adiponectin and HOMA-IR). Compared with obese controls (OC), children with PWS had fasting hyperghrelinaemia, hyperadiponectinaemia, hypoinsulinaemia and increased ghrelin/PYY. Hyperghrelinaemia, hyperadiponectinaemia and hypoinsulinaemia were more striking in PWS females than males, and decreases in BCAA were detected only in PWS females. GH-treated PWS subjects had lower leptin and higher IGF-1 and adiponectin than untreated subjects; fasting ghrelin, PYY and insulin levels were comparable. Ghrelin correlated inversely with BCAA in PWS but not OC. Adiponectin correlated negatively with BMIz and HOMA-IR in PWS; in contrast, adiponectin correlated more strongly with BCAA than BMIz or HOMA-IR in OC. BCAA levels were lower in PWS females than OC females and correlated inversely with ghrelin. Low BCAA in PWS females may promote hyperghrelinaemia and hyperphagia, while hyperadiponectinaemia may maintain insulin sensitivity despite excess weight gain. GH treatment may reduce leptin and increase adiponectin, but does not affect fasting ghrelin or PYY. © 2015 John Wiley & Sons Ltd.

Metabolic profiling in Prader-Willi syndrome and non-syndromic obesity: sex differences and the role of growth hormone

PubMed Central

Irizarry, Krystal A.; Bain, James; Butler, Merlin G.; Ilkayeva, Olga; Muehlbauer, Michael; Haqq, Andrea M.; Freemark, Michael

2015-01-01

Objectives To identify metabolic factors controlling appetite and insulin sensitivity in PWS and assess effects of GH treatment. Methods We compared amino acids, fatty acids, and acylcarnitines in GH-treated and untreated PWS children and obese and lean controls to identify biomarkers associated with ghrelin, peptide YY, and markers of insulin sensitivity (adiponectin and HOMA-IR). Results Compared with obese controls (OC), children with PWS had hyperghrelinemia, hyperadiponectinemia, hypoinsulinemia, and increased ghrelin/PYY. Hyperghrelinemia, hyperadiponectinemia, and hypoinsulinemia were more striking in PWS females than males and decreases in BCAA were detected only in PWS females. GH-treated PWS subjects had lower leptin and higher IGF-1 and adiponectin than untreated subjects; ghrelin, PYY, and insulin levels were comparable. Ghrelin correlated inversely with BCAA in PWS but not OC. Adiponectin correlated negatively with BMIz and HOMA-IR in PWS; in contrast, adiponectin correlated more strongly with BCAA than BMIz or HOMA-IR in OC. Conclusions BCAA levels were lower in PWS females than OC females and correlated inversely with ghrelin. Low BCAA in PWS females may promote hyperghrelinemia and hyperphagia, while hyperadiponectinemia may maintain insulin sensitivity despite excess weight gain. GH treatment may reduce leptin and increase adiponectin, but does not affect ghrelin or PYY. PMID:25736874

A longitudinal study of serum insulin and insulin resistance as predictors of weight and body fat gain in African American and Caucasian children

PubMed Central

Sedaka, Nicole M.; Olsen, Cara H.; Yannai, Laura E.; Stutzman, William E.; Krause, Amanda J.; Sherafat-Kazemzadeh, Roya; Condarco, Tania A.; Brady, Sheila M.; Demidowich, Andrew P.; Reynolds, James C.; Yanovski, Susan Z; Hubbard, Van S; Yanovski, Jack A

2016-01-01

Background The influence of insulin and insulin resistance (IR) on children’s weight and fat gain is unclear. Objective To evaluate insulin and IR as predictors of weight and body fat gain in children at high-risk for adult obesity. We hypothesized that baseline IR would be positively associated with follow-up BMI and fat mass. Subjects/Methods 249 healthy African American and Caucasian children, age 6–12y, at high-risk for adult obesity because of early-onset childhood overweight and/or parental overweight, were followed for up to 15y with repeated BMI and fat mass measurements. We examined baseline serum insulin and HOMA-IR as predictors of follow-up BMI Z score and fat mass by DEXA in mixed model longitudinal analyses accounting for baseline body composition, pubertal stage, sociodemographic factors, and follow-up interval. Results At baseline, 39% were obese (BMI ≥95th percentile for age/sex). Data from 1,335 annual visits were examined. Children were followed for an average of 7.2±4.3y, with a maximum follow up of 15 years. After accounting for covariates, neither baseline insulin nor HOMA-IR was significantly associated with follow up BMI (p’s>.26), BMIz score (p’s>.22), fat mass (p’s>.78), or fat mass percentage (p’s>.71). In all models, baseline BMI (p<.0001), body fat mass (p<.0001), and percentage fat (p<.001) were strong positive predictors for change in BMI and fat mass. In models restricted to children without obesity at baseline, some but not all models had significant interaction terms between body adiposity and insulinemia/HOMA-IR that suggested less gain in mass among those with greater insulin or insulin resistance. The opposite was found in some models restricted to children with obesity at baseline. Conclusions In middle childhood, BMI and fat mass, but not insulin or IR, are strong predictors of children’s gains in BMI and fat mass during adolescence. PMID:27534840

Group 1B phospholipase A₂ inactivation suppresses atherosclerosis and metabolic diseases in LDL receptor-deficient mice.

PubMed

Hollie, Norris I; Konaniah, Eddy S; Goodin, Colleen; Hui, David Y

2014-06-01

Previous studies have shown that inactivation of the group 1B phospholipase A2 (Pla2g1b) suppresses diet-induced obesity, hyperglycemia, insulin resistance, and hyperlipidemia in C57BL/6 mice. A possible influence of Pla2g1b inactivation on atherosclerosis has not been addressed previously. The current study utilized LDL receptor-deficient (Ldlr(-/-)) mice with plasma lipid levels and distribution similar to hyperlipidemic human subjects as a preclinical animal model to test the effectiveness of Pla2g1b inactivation on atherosclerosis. The Pla2g1b(+/+)Ldlr(-/-) and Pla2g1b(-/-)Ldlr(-/-) mice were fed a low fat chow diet or a hypercaloric diet with 58.5 kcal% fat and 25 kcal% sucrose for 10 weeks. Minimal differences were observed between Pla2g1b(+/+)Ldlr(-/-) and Pla2g1b(-/-)Ldlr(-/-) mice when the animals were maintained on the low fat chow diet. However, when the animals were maintained on the hypercaloric diet, the Pla2g1(+/+)Ldlr(-/-) mice showed the expected body weight gain but the Pla2g1b(-/-)Ldlr(-/-) mice were resistant to diet-induced body weight gain. The Pla2g1b(-/-)Ldlr(-/-) mice also displayed lower fasting glucose, insulin, and plasma lipid levels compared to the Pla2g1b(+/+)Ldlr(-/-) mice, which displayed robust hyperglycemia, hyperinsulinemia, and hyperlipidemia in response to the hypercaloric diet. Importantly, atherosclerotic lesions in the aortic roots were also reduced 7-fold in the Pla2g1b(-/-)Ldlr(-/-) mice. The effectiveness of Pla2g1b inactivation to suppress diet-induced body weight gain and reduce diabetes and atherosclerosis in LDL receptor-deficient mice suggests that pharmacological inhibition of Pla2g1b may be a viable strategy to decrease diet-induced obesity and the risk of diabetes and atherosclerosis in humans. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Metformin for treatment of antipsychotic-induced weight gain: a randomized, placebo-controlled study.

PubMed

Wang, Man; Tong, Jian-hua; Zhu, Gang; Liang, Guang-ming; Yan, Hong-fei; Wang, Xiu-zhen

2012-06-01

To evaluate the efficacy of metformin for treatment of antipsychotic-induced weight gain. Seventy-two patients with first-episode schizophrenia who gained more than 7% of their predrug weight were randomly assigned to receive 1000 mg/d of metformin or placebo in addition to their ongoing treatment for 12 weeks using a double-blind study design. The primary outcome was change in body weight. The secondary outcomes included changes in body mass index, fasting glucose and insulin, and insulin resistance index. Of the 72 patients who were randomly assigned, 66 (91.6%) completed treatments. The body weight, body mass index, fasting insulin and insulin resistance index decreased significantly in the metformin group, but increased in the placebo group during the 12-week follow-up period. Significantly more patients in the metformin group lost their baseline weight by more than 7%, which was the cutoff for clinically meaningful weight loss. Metformin was tolerated well by majority patients. Metformin was effective and safe in attenuating antipsychotic-induced weight gain and insulin resistance in first-episode schizophrenia patients. Patients displayed good adherence to metformin. Copyright © 2012 Elsevier B.V. All rights reserved.

Potential Underlying Mechanisms for Greater Weight Gain in Massaged Preterm Infants

PubMed Central

Field, Tiffany; Diego, Miguel; Hernandez-Reif, Maria

2010-01-01

In this paper, potential underlying mechanisms for massage therapy effects on preterm infant weight gain are reviewed. Path analyses are presented suggesting that: 1) increased vagal activity was associated with 2) increased gastric motility, which, in turn, was related to 3) greater weight gain; and 4) increased IGF-1 was related to greater weight gain. The change in vagal activity during the massage explained 49% of the variance in the change in gastric activity. And, the change in vagal activity during the massage explained 62% of the variance in the change in insulin. That the change in gastric activity was not related to the change in insulin suggests two parallel pathways via which massage therapy leads to increased weight gain: 1) insulin release via the celiac branch of the vagus; and 2) increased gastric activity via the gastric branch of the vagus. PMID:21570125

Improvement of Insulin Secretion and Pancreatic β-cell Function in Streptozotocin-induced Diabetic Rats Treated with Aloe vera Extract

PubMed Central

Noor, Ayesha; Gunasekaran, S.; Vijayalakshmi, M. A.

2017-01-01

Background: Diabetes mellitus is a metabolic disorder characterized by chronic hyperglycemia. Plant extracts and their products are being used as an alternative system of medicine for the treatment of diabetes. Aloe vera has been traditionally used to treat several diseases and it exhibits antioxidant, anti-inflammatory, and wound-healing effects. Streptozotocin (STZ)-induced Wistar diabetic rats were used in this study to understand the potential protective effect of A. vera extract on the pancreatic islets. Objective: The aim of the present study was to evaluate the A. vera extract on improvement of insulin secretion and pancreatic β-cell function by morphometric analysis of pancreatic islets in STZ-induced diabetic Wistar rats. Materials and Methods: After acclimatization, male Wistar rats, maintained as per the Committee for the Purpose of Control and Supervision of Experiments on Animals guidelines, were randomly divided into four groups of six rats each. Fasting plasma glucose and insulin levels were assessed. The effect of A. vera extract in STZ-induced diabetic rats on the pancreatic islets by morphometric analysis was evaluated. Results: Oral administration of A. vera extract (300 mg/kg) daily to diabetic rats for 3 weeks showed restoration of blood glucose levels to normal levels with a concomitant increase in insulin levels upon feeding with A. vera extract in STZ-induced diabetic rats. Morphometric analysis of pancreatic sections revealed quantitative and qualitative gain in terms of number, diameter, volume, and area of the pancreatic islets of diabetic rats treated with A. vera extract when compared to the untreated diabetic rats. Conclusion: A. vera extract exerts antidiabetic effects by improving insulin secretion and pancreatic β-cell function by restoring pancreatic islet mass in STZ-induced diabetic Wistar rats. SUMMARY Fasting plasma glucose (FPG) and insulin levels were restored to normal levels in diabetic rats treated with Aloe vera extractIslets of pancreas were qualitatively and quantitatively restored to normalcy leading to restoration of FPG and insulin levels of diabetic rats treated with Aloe vera extractMorphometric analysis of pancreatic sections revealed quantitative and qualitative gain in terms of number, diameter, volume, and area of the pancreatic islets of diabetic rats treated with Aloe vera extract when compared to the untreated diabetic rats. Abbreviations Used: A. vera, FPG: Fasting plasma glucose, STZ: Streptozotocin, BW: Body weight PMID:29333050

Body fat mass and the proportion of very large adipocytes in pregnant women are associated with gestational insulin resistance

PubMed Central

Svensson, H; Wetterling, L; Bosaeus, M; Odén, B; Odén, A; Jennische, E; Edén, S; Holmäng, A; Lönn, M

2016-01-01

Background/Objectives: Pregnancy is accompanied by fat gain and insulin resistance. Changes in adipose tissue morphology and function during pregnancy and factors contributing to gestational insulin resistance are incompletely known. We sought to characterize adipose tissue in trimesters 1 and 3 (T1/T3) in normal weight (NW) and obese pregnant women, and identify adipose tissue-related factors associated with gestational insulin resistance. Subjects/Methods: Twenty-two NW and 11 obese women were recruited early in pregnancy for the Pregnancy Obesity Nutrition and Child Health study. Examinations and sampling of blood and abdominal adipose tissue were performed longitudinally in T1/T3 to determine fat mass (air-displacement plethysmography); insulin resistance (homeostasis model assessment of insulin resistance, HOMA-IR); size, number and lipolytic activity of adipocytes; and adipokine release and density of immune cells and blood vessels in adipose tissue. Results: Fat mass and HOMA-IR increased similarly between T1 and T3 in the groups; all remained normoglycemic. Adipocyte size increased in NW women. Adipocyte number was not influenced, but proportions of small and large adipocytes changed oppositely in the groups. Lipolytic activity and circulating adipocyte fatty acid-binding protein increased in both groups. Adiponectin release was reduced in NW women. Fat mass and the proportion of very large adipocytes were most strongly associated with T3 HOMA-IR by multivariable linear regression (R2=0.751, P<0.001). Conclusions: During pregnancy, adipose tissue morphology and function change comprehensively. NW women accumulated fat in existing adipocytes, accompanied by reduced adiponectin release. In comparison with the NW group, obese women had signs of adipocyte recruitment and maintained adiponectin levels. Body fat and large adipocytes may contribute significantly to gestational insulin resistance. PMID:26563815

Body fat mass and the proportion of very large adipocytes in pregnant women are associated with gestational insulin resistance.

PubMed

Svensson, H; Wetterling, L; Bosaeus, M; Odén, B; Odén, A; Jennische, E; Edén, S; Holmäng, A; Lönn, M

2016-04-01

Pregnancy is accompanied by fat gain and insulin resistance. Changes in adipose tissue morphology and function during pregnancy and factors contributing to gestational insulin resistance are incompletely known. We sought to characterize adipose tissue in trimesters 1 and 3 (T1/T3) in normal weight (NW) and obese pregnant women, and identify adipose tissue-related factors associated with gestational insulin resistance. Twenty-two NW and 11 obese women were recruited early in pregnancy for the Pregnancy Obesity Nutrition and Child Health study. Examinations and sampling of blood and abdominal adipose tissue were performed longitudinally in T1/T3 to determine fat mass (air-displacement plethysmography); insulin resistance (homeostasis model assessment of insulin resistance, HOMA-IR); size, number and lipolytic activity of adipocytes; and adipokine release and density of immune cells and blood vessels in adipose tissue. Fat mass and HOMA-IR increased similarly between T1 and T3 in the groups; all remained normoglycemic. Adipocyte size increased in NW women. Adipocyte number was not influenced, but proportions of small and large adipocytes changed oppositely in the groups. Lipolytic activity and circulating adipocyte fatty acid-binding protein increased in both groups. Adiponectin release was reduced in NW women. Fat mass and the proportion of very large adipocytes were most strongly associated with T3 HOMA-IR by multivariable linear regression (R(2)=0.751, P<0.001). During pregnancy, adipose tissue morphology and function change comprehensively. NW women accumulated fat in existing adipocytes, accompanied by reduced adiponectin release. In comparison with the NW group, obese women had signs of adipocyte recruitment and maintained adiponectin levels. Body fat and large adipocytes may contribute significantly to gestational insulin resistance.

Novel Podophyllotoxin Derivatives as Partial PPARγ Agonists and their Effects on Insulin Resistance and Type 2 Diabetes.

PubMed

Zhang, Xiangming; Liu, Huijuan; Sun, Bo; Sun, Yan; Zhong, Weilong; Liu, Yanrong; Chen, Shuang; Ling, Honglei; Zhou, Lei; Jing, Xiangyan; Qin, Yuan; Xiao, Ting; Sun, Tao; Zhou, Honggang; Yang, Cheng

2016-11-17

Peroxisome proliferator-activated receptor γ (PPARγ) is recognized as a key regulator of insulin resistance. In this study, we searched for novel PPARγ agonists in a library of structurally diverse organic compounds and determined that podophyllotoxin exhibits partial agonist activity toward PPARγ. Eight novel podophyllotoxin-like derivatives were synthesized and assayed for toxicity and functional activity toward PPARγ to reduce the possible systemic toxic effects of podophyllotoxin and to maintain partial agonist activity toward PPARγ. Cell-based transactivation assays showed that compounds (E)-3-(hydroxy(3,4,5-trimethoxyphenyl)methyl)-4-(4(trifluoromethyl)styryl)dihydrofuran-2(3H)-one (3a) and (E)-4-(3-acetylstyryl)-3-(hydroxyl (3,4,5-trimethoxyphenyl)methyl)dihydrofuran-2(3H)-one (3f) exhibited partial agonist activity. An experiment using human hepatocarcinoma cells (HepG2) that were induced to become an insulin-resistant model showed that compounds 3a and 3f improved insulin sensitivity and glucose consumption. In addition, compounds 3a and 3f significantly improved hyperglycemia and insulin resistance in high-fat diet-fed streptozotocin (HFD-STZ)-induced type 2 diabetic rats at a dose of 15 mg/kg/day administered orally for 45 days, without significant weight gain. Cell toxicity testing also showed that compounds 3a and 3f exhibited weaker toxicity than pioglitazone. These findings suggested that compounds 3a and 3f improved insulin resistance in vivo and in vitro and that the compounds exhibited potential for the treatment of type 2 diabetes mellitus.

Repaglinide versus metformin in combination with bedtime NPH insulin in patients with type 2 diabetes established on insulin/metformin combination therapy.

PubMed

Furlong, Niall J; Hulme, Shirley A; O'Brien, Sarah V; Hardy, Kevin J

2002-10-01

To compare the effect on glycemic control and weight gain of repaglinide versus metformin combined with bedtime NPH insulin in patients with type 2 diabetes. A total of 80 subjects treated with 850 or 1,000 mg t.i.d. metformin combined with bedtime NPH insulin were randomized to 13 weeks of open-label treatment with 4 mg t.i.d. repaglinide (n = 39) or metformin (dose unchanged) (n = 41). Insulin dose was titrated at the clinician's discretion, aiming for a fasting blood glucose (FBG) < or =6.0 mmol/l. Baseline age, diabetes duration, insulin requirement, weight, BMI, FBG, and HbA(1c) (Diabetes Control and Complications Trial-aligned assay, normal range 4.6-6.2%) were similar. Glycemic control improved (nonsignificantly) with insulin/metformin by (mean) 0.4%, from 8.4 to 8.1% (P = 0.09) but deteriorated with insulin/repaglinide by (mean) 0.4%, from 8.1 to 8.6% (P = 0.03; P = 0.005 between groups). Weight gain was less with insulin/metformin: 0.9 +/- 0.4 kg (means +/- SE) (P = 0.01) versus 2.7 +/- 0.4 kg (P < 0.0001) (P = 0.002 between groups). The Diabetes Treatment Satisfaction Questionnaire score (potential range 0 [minimum] to 36 [maximum]) increased from 32.4 +/- 0.8 to 34.1 +/- 0.5 (P = 0.01) with insulin/metformin but decreased from 32.5 +/- 0.9 to 29.1 +/- 1.3 (P < 0.002) with insulin/repaglinide. Combined with bedtime NPH insulin, metformin provides superior glycemic control to repaglinide with less weight gain and improved diabetes treatment satisfaction.

A longitudinal study of serum insulin and insulin resistance as predictors of weight and body fat gain in African American and Caucasian children.

PubMed

Sedaka, N M; Olsen, C H; Yannai, L E; Stutzman, W E; Krause, A J; Sherafat-Kazemzadeh, R; Condarco, T A; Brady, S M; Demidowich, A P; Reynolds, J C; Yanovski, S Z; Hubbard, V S; Yanovski, J A

2017-01-01

The influence of insulin and insulin resistance (IR) on children's weight and fat gain is unclear. To evaluate insulin and IR as predictors of weight and body fat gain in children at high risk for adult obesity. We hypothesized that baseline IR would be positively associated with follow-up body mass index (BMI) and fat mass. Two hundred and forty-nine healthy African American and Caucasian children aged 6-12 years at high risk for adult obesity because of early-onset childhood overweight and/or parental overweight were followed for up to 15 years with repeated BMI and fat mass measurements. We examined baseline serum insulin and homeostasis model of assessment-IR (HOMA-IR) as predictors of follow-up BMI Z-score and fat mass by dual-energy X-ray absorptiometry in mixed model longitudinal analyses accounting for baseline body composition, pubertal stage, sociodemographic factors and follow-up interval. At baseline, 39% were obese (BMI⩾95th percentile for age/sex). Data from 1335 annual visits were examined. Children were followed for an average of 7.2±4.3 years, with a maximum follow-up of 15 years. After accounting for covariates, neither baseline insulin nor HOMA-IR was significantly associated with follow-up BMI (Ps>0.26), BMIz score (Ps>0.22), fat mass (Ps>0.78) or fat mass percentage (Ps>0.71). In all models, baseline BMI (P<0.0001), body fat mass (P<0.0001) and percentage of fat (P<0.001) were strong positive predictors for change in BMI and fat mass. In models restricted to children without obesity at baseline, some but not all models had significant interaction terms between body adiposity and insulinemia/HOMA-IR that suggested less gain in mass among those with greater insulin or IR. The opposite was found in some models restricted to children with obesity at baseline. In middle childhood, BMI and fat mass, but not insulin or IR, are strong predictors of children's gains in BMI and fat mass during adolescence.

Metabolic impact of switching antipsychotic therapy to aripiprazole after weight gain: a pilot study.

PubMed

Kim, Sun H; Ivanova, Oxana; Abbasi, Fahim A; Lamendola, Cindy A; Reaven, Gerald M; Glick, Ira D

2007-08-01

Switching antipsychotic regimen to agents with low weight gain potential has been suggested in patients who gain excessive weight on their antipsychotic therapy. In an open-label pilot study, we evaluated the metabolic and psychiatric efficacy of switching to aripiprazole in 15 (9 men, 6 women) outpatients with schizophrenia who had gained at least 10 kg on their previous antipsychotic regimen. Individuals had evaluation of glucose tolerance, insulin resistance (insulin suppression test), lipid concentrations, and psychiatric status before and after switching to aripiprazole for 4 months. A third of the individuals could not psychiatrically tolerate switching to aripiprazole. In the remaining individuals, psychiatric symptoms significantly improved with decline in Clinical Global Impression Scale (by 26%, P = 0.015) and Positive and Negative Syndrome Scale (by 22%, P = 0.023). Switching to aripiprazole did not alter weight or metabolic outcomes (fasting glucose, insulin resistance, and lipid concentrations) in the patients of whom 73% were insulin resistant and 47% had impaired or diabetic glucose tolerance at baseline. In conclusion, switching to aripiprazole alone does not ameliorate the highly prevalent metabolic abnormalities in the schizophrenia population who have gained weight on other second generation antipsychotic medications.

Antidepressant-like Effect of Insulin in Streptozotocin-induced Type 2 Diabetes Mellitus Rats.

PubMed

Sestile, Caio C; Maraschin, Jhonatan C; Rangel, Marcel P; Cuman, Roberto K N; Audi, Elisabeth A

2016-09-01

This study evaluated the antidepressant-like effect of insulin compared to sertraline and a combination of insulin and sertraline in streptozotocin (STZ)-induced type 2 diabetes mellitus (T2DM) rats submitted to the forced swim test (FST). Male Wistar rats were daily treated for 21 days with insulin (1 or 2 IU/kg, i.p.), with the selective serotonin reuptake inhibitor (SSRI), sertraline (10 mg/kg, i.p.), or with a combination of insulin (1 or 2 IU/kg, i.p.) and sertraline (10 mg/kg, i.p.) and submitted to the FST. We also evaluated the water and food intake, urine volume and weight gain of the rats. Rats treated with STZ showed impaired glucose tolerance. Chronic treatment with sertraline showed an antidepressant-like effect in non-diabetic and diabetic rats. Furthermore, sertraline promoted lower weight gain in diabetic rats. Insulin reduced the immobility behaviour in T2DM rats with impaired glucose tolerance. In conclusion, our results showed that insulin has an antidepressant-like effect comparable to that of sertraline. Sertraline is effective as an antidepressant and reduces weight gain, which reinforces its superiority over other SSRIs in the treatment of major depression disorder in patients with T2DM. © 2016 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

Improvement and emergence of insulin restriction in women with type 1 diabetes.

PubMed

Goebel-Fabbri, Ann E; Anderson, Barbara J; Fikkan, Janna; Franko, Debra L; Pearson, Kimberly; Weinger, Katie

2011-03-01

To determine the distinguishing characteristics of women who report stopping insulin restriction at 11 years of follow-up from those continuing to endorse insulin restriction as well as those characteristics differing in patients who continue to use insulin appropriately from new insulin restrictors. This is an 11-year follow-up study of 207 women with type 1 diabetes. Insulin restriction, diabetes self-care behaviors, diabetes-specific distress, and psychiatric and eating disorder symptoms were assessed using self-report surveys. Of the original sample, 57% participated in the follow-up study. Mean age was 44 ± 12 years, diabetes duration was 28 ± 11 years, and A1C was 7.9 ± 1.3%. At follow-up, 20 of 60 baseline insulin restrictors had stopped restriction. Women who stopped reported improved diabetes self-care and distress, fewer problems with diabetes self-management, and lower levels of psychologic distress and eating disorder symptoms. Logistic regression indicated that lower levels of fear of weight gain with improved blood glucose and fewer problems with diabetes self-management predicted stopping restriction. At follow-up, 34 women (23%) reported new restriction, and a larger proportion of new insulin restrictors, relative to nonrestrictors, endorsed fear of weight gain with improved blood glucose. Findings indicate that fear of weight gain associated with improved blood glucose and problems with diabetes self-care are core issues related to both the emergence and resolution of insulin restriction. Greater attention to these concerns may help treatment teams to better meet the unique treatment needs of women struggling with insulin restriction.

Systematic Review of the Cost Effectiveness of Insulin Analogues in Type 1 and Type 2 Diabetes Mellitus.

PubMed

Shafie, Asrul Akmal; Ng, Chin Hui; Tan, Yui Ping; Chaiyakunapruk, Nathorn

2017-02-01

Insulin analogues have a pharmacokinetic advantage over human insulin and are increasingly used to treat diabetes mellitus. A summary of their cost effectiveness versus other available treatments was required. Our objective was to systematically review the published cost-effectiveness studies of insulin analogues for the treatment of patients with type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). We searched major databases and health technology assessment agency reports for economic evaluation studies published up until 30 September 2015. Two reviewers performed data extraction and assessed the quality of the data using the CHEERS (Consolidated Health Economic Evaluation Reporting Standards) guidelines. Seven of the included studies assessed short-acting insulin analogues, 12 assessed biphasic insulin analogues, 30 assessed long-acting insulin analogues and one assessed a combination of short- and long-acting insulin analogues. Only 17 studies involved patients with T1DM, all were modelling studies and 12 were conducted in Canada. The incremental cost-effectiveness ratios (ICERs) for short-acting insulin analogues ranged from dominant to $US435,913 per quality-adjusted life-year (QALY) gained, the ICERs for biphasic insulin analogues ranged from dominant to $US57,636 per QALY gained and the ICERs for long-acting insulin analogues ranged from dominant to $US599,863 per QALY gained. A total of 15 studies met all the CHEERS guidelines reporting quality criteria. Only 26 % of the studies assessed heterogeneity in their analyses. Current evidence indicates that insulin analogues are cost effective for T1DM; however, evidence for their use in T2DM is not convincing. Additional evidence regarding compliance and efficacy is required to support the broader use of long-acting and biphasic insulin analogues in T2DM. The value of insulin analogues depends strongly on reductions in hypoglycaemia event rates and its efficacy in lowering glycated haemoglobin (HbA 1c ).

Rare sugar D-allulose: Potential role and therapeutic monitoring in maintaining obesity and type 2 diabetes mellitus.

PubMed

Hossain, Akram; Yamaguchi, Fuminori; Matsuo, Tatsuhiro; Tsukamoto, Ikuko; Toyoda, Yukiyasu; Ogawa, Masahiro; Nagata, Yasuo; Tokuda, Masaaki

2015-11-01

Obesity and type 2 diabetes mellitus (T2DM) are the leading worldwide risk factors for mortality. The inextricably interlinked pathological progression from excessive weight gain, obesity, and hyperglycemia to T2DM, usually commencing from obesity, typically originates from overconsumption of sugar and high-fat diets. Although most patients require medications, T2DM is manageable or even preventable with consumption of low-calorie diet and maintaining body weight. Medicines like insulin, metformin, and thiazolidinediones that improve glycemic control; however, these are associated with weight gain, high blood pressure, and dyslipidemia. These situations warrant the attentive consideration of the role of balanced foods. Recently, we have discovered advantages of a rare sugar, D-allulose, a zero-calorie functional sweetener having strong anti-hyperlipidemic and anti-hyperglycemic effects. Study revealed that after oral administration in rats D-allulose readily entered the blood stream and was eliminated into urine within 24h. Cell culture study showed that D-allulose enters into and leaves the intestinal enterocytes via glucose transporters GLUT5 and GLUT2, respectively. In addition to D-allulose's short-term effects, the characterization of long-term effects has been focused on preventing commencement and progression of T2DM in diabetic rats. Human trials showed that D-allulose attenuates postprandial glucose levels in healthy subjects and in borderline diabetic subjects. The anti-hyperlipidemic effect of D-allulose, combined with its anti-inflammatory actions on adipocytes, is beneficial for the prevention of both obesity and atherosclerosis and is accompanied by improvements in insulin resistance and impaired glucose tolerance. Therefore, this review presents brief discussions focusing on physiological functions and potential benefits of D-allulose on obesity and T2DM. Copyright © 2015 Elsevier Inc. All rights reserved.

A cost-controlling treatment strategy of adding liraglutide to insulin in type 2 diabetes.

PubMed

de Wit, H M; Vervoort, G M M; de Galan, B E; Tack, C J

2017-09-01

Addition of the GLP-1 receptor agonist liraglutide to insulin can reverse insulin-associated weight gain, improve HbA1c and decrease the need for insulin, but is expensive. From a cost perspective, such treatment should be discontinued when it is clear that treatment targets will not be achieved. Our aim was to find the best cost-controlling treatment strategy: the shortest possible trial period needed to discriminate successfully treated patients from those failing to achieve predefined targets of treatment success. We used data from the 'Effect of Liraglutide on insulin-associated wEight GAiN in patients with Type 2 diabetes' (ELEGANT) trial, comparing additional liraglutide (n = 47) and standard insulin therapy (n = 24) during 26 weeks, to calculate the costs associated with different trial periods. Treatment success after 26 weeks was defined by having achieved ≥ 2 of the following: ≥ 4% weight loss, HbA1c ≤ 53 mmol/mol (7%), and/or discontinuation of insulin. The additional direct costs of adding liraglutide for 26 weeks were € 699 per patient, or € 137 per 1 kg weight loss, compared with standard therapy. The best cost-controlling treatment strategy (identifying 21 of 23 responders, treating four non-responders) was to continue treatment in patients showing ≥ 3% weight loss or ≥ 60% decrease in insulin dose at 8 weeks, with a total cost of € 246 for this t rial period, saving € 453 in case of early discontinuation. An 8-week trial period of adding liraglutide to insulin in patients with insulin-associated weight gain is an effective cost-controlling treatment strategy if the liraglutide is discontinued in patients not showing an early response regarding weight loss or insulin reduction.

Intramyocellular Lipid Droplet Size Rather Than Total Lipid Content is Related to Insulin Sensitivity After 8 Weeks of Overfeeding.

PubMed

Covington, Jeffrey D; Johannsen, Darcy L; Coen, Paul M; Burk, David H; Obanda, Diana N; Ebenezer, Philip J; Tam, Charmaine S; Goodpaster, Bret H; Ravussin, Eric; Bajpeyi, Sudip

2017-12-01

Intramyocellular lipid (IMCL) is inversely related to insulin sensitivity in sedentary populations, yet no prospective studies in humans have examined IMCL accumulation with overfeeding. Twenty-nine males were overfed a high-fat diet (140% caloric intake, 44% from fat) for 8 weeks. Measures of IMCL, whole-body fat oxidation from a 24-hour metabolic chamber, muscle protein extracts, and muscle ceramide measures were obtained before and after the intervention. Eight weeks of overfeeding did not increase overall IMCL. The content of smaller lipid droplets peripherally located in the myofiber decreased, while increases in larger droplets correlated inversely with glucose disposal rate. Overfeeding resulted in inhibition of Akt activity, which correlated with the reductions in smaller, peripherally located lipid droplets and drastic increases in ceramide content. Additionally, peripherally located lipid droplets were associated with more efficient lipid oxidation. Finally, participants who maintained a greater number of smaller, peripherally located lipid droplets displayed a better resistance to weight gain with overfeeding. These results show that lipid droplet size and location rather than mere IMCL content are important to understanding insulin sensitivity. © 2017 The Obesity Society.

Dipeptidyl peptidase-4 inhibitors or sodium glucose co-transporter-2 inhibitors as an add-on to insulin therapy: A comparative review

PubMed Central

Singh, Awadhesh Kumar; Singh, Ritu

2016-01-01

The gradual decline in β-cell function is inevitable in type 2 diabetes mellitus and therefore, substantial proportions of patients require insulin subsequently, in order to achieve optimal glucose control. While weight gain, hypoglycemia, and fluid retention especially during dose intensification is a known limitation to insulin therapy, these adverse effects also reduce patient satisfaction and treatment adherence. It is also possible that the benefits of intensive control achieved by insulin therapy, perhaps get nullified by the weight gain and hypoglycemia. In addition, improvement in plasma glucose or glycated hemoglobin (HbA1c) itself is associated with weight gain. Notably, studies have already suggested that reduction in body weight by ~3–5%, may allow a significantly better glycemic control. Thus, a class of drugs, which can reduce HbA1c effectively, yet are weight neutral or preferably reduce body weight, could be the most sought out strategy as an add-on therapy to insulin. While sulfonylureas (SUs) are associated with weight gain and hypoglycemia, pioglitazone increases body weight and fluid retention. Moreover, SUs are not recommended once premix or prandial insulin is commenced. The addition of newer agents, such as glucagon-like peptide-1 receptor agonist to insulin certainly appears to be an effective tool in reducing both HbA1c and body weight as is evident across the studies; however, this approach incurs an additional injection as well as cost. Dipeptidyl peptidase-4 inhibitors (DPP-4I) and sodium-glucose co-transporter-2 inhibitors (SGLT-2I) are other exciting options, as an add-on to insulin therapy primarily because these are oral drugs and do not possess any intrinsic potential of hypoglycemia. Furthermore, these are either weight neutral or induce significant weight loss. This review article aims to comparatively analyze the safety and efficacy of DPP-4I and SGLT-2I, as an add-on therapy to insulin. PMID:26904466

Evaluating drug cost per responder and number needed to treat associated with lixisenatide on top of glargine when compared to rapid-acting insulin intensification regimens on top of glargine, in patients with type 2 diabetes in the UK, Italy, and Spain.

PubMed

Afonso, Marion; Ryan, Fay; Pitcher, Ashley; Lew, Elisheva

2017-06-01

This study investigated the cost per responder and number needed to treat (NNT) in type 2 diabetes mellitus (T2DM) patients for lixisenatide compared to insulin intensification regimens using composite endpoints in the UK, Italy, and Spain. Efficacy and safety outcomes were obtained from GetGoal Duo-2, a 26-week phase 3 trial comparing lixisenatide vs insulin glulisine (IG) once daily (QD) and three times daily (TID). Response at week 26 was extrapolated to 52 weeks, assuming a maintained treatment effect, based on long-term evidence in other T2DM populations. Responders were defined using composite end-points, based on an HbA1c threshold and/or no weight gain and/or no hypoglycemia. The HbA1c threshold was varied in sensitivity analyses. Annual treatment costs were estimated in euros (1 GBP = 1.26 EUR), including drug acquisition and resource use costs. Cost per responder was computed by dividing annual treatment costs per patient by the proportion of responders. Lixisenatide was associated with the lowest cost per responder for all composite end-points that included a weight-related component. For the main composite end-point of HbA1c ≤7.5% AND no weight gain AND no symptomatic hypoglycemia, cost per responder results were: UK: 6,867€, 8,746€, and 12,410€; Italy: 7,057€, 9,160€, and 12,844€; Spain: 8,370€, 11,365€, and 17,038€, for lixisenatide, IG QD, and TID, respectively. The NNT analysis showed that, for every 6.85 and 5.86 patients treated with lixisenatide, there was approximately one additional responder compared to IG QD and TID, respectively. A limitation of the clinical inputs is the lack of 52-week trial data from GetGoal Duo-2, which led to the assumption of a maintained treatment effect from week 26 to 52. This analysis suggests lixisenatide is an efficient economic resource allocation in the UK, Italy, and Spain.

Pronounced weight gain in insulin-treated patients with type 2 diabetes mellitus is associated with an unfavourable cardiometabolic risk profile.

PubMed

Jansen, H J; Vervoort, G; van der Graaf, M; Tack, C J

2010-11-01

Pronounced weight gain after start of insulin therapy in patients with type 2 diabetes mellitus (T2DM) may offset beneficial effects conferred by the improvement of glycaemic control. This hypothesis was tested by comparing the cardiometabolic risk profile of a group of type 2 diabetes patients with a marked increase in body weight ('gainers) after the start of insulin treatment and a similar group without any or only minimal weight gain ('non-gainers'). In a cross-sectional study, we compared two predefined groups of patients with T2DM who had been on insulin therapy for a mean of 4.0 years: 'gainers' vs 'non-gainers'. Cardiometabolic risk was assessed by measuring fat content and distribution (physical examination, bioelectrical impedance analysis, dual energy X-ray absorption, and magnetic resonance imaging), liver fat content (magnetic resonance spectroscopy), physical activity levels (Sensewear® armband) and plasma markers. Each subgroup consisted of 14 patients. Gainers had significantly more total body and trunk fat (especially subcutaneous fat) compared with no-gainers. Gainers had similar liver fat content, and slightly higher levels of fat hormones. Furthermore, gainers performed significantly less physical activity. Lastly, gainers had higher total cholesterol, low-density lipoprotein cholesterol, and alanine aminotransferase levels with similar cholesterol-lowering treatment. Patients with T2DM who show pronounced weight gain during insulin therapy have a less favourable cardiometabolic risk profile compared with patients who show no or minimal weight gain.

Pre-teen insulin resistance predicts weight gain, impaired fasting glucose, and type 2 diabetes at age 18-19 y: a 10-y prospective study of black and white girls.

PubMed

Morrison, John A; Glueck, Charles J; Horn, Paul S; Schreiber, George B; Wang, Ping

2008-09-01

Identifying early pre-teen predictors of adolescent weight gain and the development of impaired fasting glucose (IFG) and type 2 diabetes (T2DM) at age 18-19 y could provide avenues for prevention. We evaluated possible pre-teen predictors for development of IFG, T2DM, and changes in body mass index at age 18-19 y in black and white girls. In a prospective cohort study, body habitus and fasting insulin and glucose were measured at ages 9-10 and 18-19 y, and multiple 3-d diet records were collected. Factors predicting 10-y change in body mass index and development of IFG and T2DM together were assessed. In multivariate analyses, 10-y change in homeostatic model assessment of insulin resistance (HOMA-IR) and the age 9-10 y HOMA-IR x percentage of calories from fat interaction were positive predictors of 10-y changes in body mass index. At age 18-19 y, there were 5 incident cases of T2DM, 37 cases of IFG, and 597 noncases. Age 9-10 y IFG and HOMA-IR (or insulin), 10-y change in HOMA-IR (or insulin), and the age 9-10 y insulin x total caloric intake interaction predicted IFG and T2DM at age 18-19 y. Pre-teen IFG, insulin resistance (and insulin), and rapidly increasing insulin resistance during adolescence identifies girls who are at greater risk of future IFG and T2DM. In addition, insulin resistance, interacting with high-fat diets, identifies girls who are at risk of greater weight gain. These findings could open avenues to primary prevention of obesity, IFG, and T2DM in children.

Improvement and Emergence of Insulin Restriction in Women With Type 1 Diabetes

PubMed Central

Goebel-Fabbri, Ann E.; Anderson, Barbara J.; Fikkan, Janna; Franko, Debra L.; Pearson, Kimberly; Weinger, Katie

2011-01-01

OBJECTIVE To determine the distinguishing characteristics of women who report stopping insulin restriction at 11 years of follow-up from those continuing to endorse insulin restriction as well as those characteristics differing in patients who continue to use insulin appropriately from new insulin restrictors. RESEARCH DESIGN AND METHODS This is an 11-year follow-up study of 207 women with type 1 diabetes. Insulin restriction, diabetes self-care behaviors, diabetes-specific distress, and psychiatric and eating disorder symptoms were assessed using self-report surveys. RESULTS Of the original sample, 57% participated in the follow-up study. Mean age was 44 ± 12 years, diabetes duration was 28 ± 11 years, and A1C was 7.9 ± 1.3%. At follow-up, 20 of 60 baseline insulin restrictors had stopped restriction. Women who stopped reported improved diabetes self-care and distress, fewer problems with diabetes self-management, and lower levels of psychologic distress and eating disorder symptoms. Logistic regression indicated that lower levels of fear of weight gain with improved blood glucose and fewer problems with diabetes self-management predicted stopping restriction. At follow-up, 34 women (23%) reported new restriction, and a larger proportion of new insulin restrictors, relative to nonrestrictors, endorsed fear of weight gain with improved blood glucose. CONCLUSIONS Findings indicate that fear of weight gain associated with improved blood glucose and problems with diabetes self-care are core issues related to both the emergence and resolution of insulin restriction. Greater attention to these concerns may help treatment teams to better meet the unique treatment needs of women struggling with insulin restriction. PMID:21266653

Insulin degludec and insulin aspart: novel insulins for the management of diabetes mellitus

PubMed Central

Atkin, Stephen; Javed, Zeeshan; Fulcher, Gregory

2015-01-01

Patients with type 2 diabetes mellitus require insulin as disease progresses to attain or maintain glycaemic targets. Basal insulin is commonly prescribed initially, alone or with one or more rapid-acting prandial insulin doses, to limit mealtime glucose excursions (a basal–bolus regimen). Both patients and physicians must balance the advantages of improved glycaemic control with the risk of hypoglycaemia and increasing regimen complexity. The rapid-acting insulin analogues (insulin aspart, insulin lispro and insulin glulisine) all have similar pharmacokinetic and pharmacodynamic characteristics and clinical efficacy/safety profiles. However, there are important differences in the pharmacokinetic and pharmacodynamic profiles of basal insulins (insulin glargine, insulin detemir and insulin degludec). Insulin degludec is an ultra-long-acting insulin analogue with a flat and stable glucose-lowering profile, a duration of action exceeding 30 h and less inter-patient variation in glucose-lowering effect than insulin glargine. In particular, the chemical properties of insulin degludec have allowed the development of a soluble co-formulation with prandial insulin aspart (insulin degludec/insulin aspart) that provides basal insulin coverage for at least 24 h with additional mealtime insulin for one or two meals depending on dose frequency. Pharmacokinetic and pharmacodynamic studies have shown that the distinct, long basal glucose-lowering action of insulin degludec and the prandial glucose-lowering effect of insulin aspart are maintained in the co-formulation. Evidence from pivotal phase III clinical trials indicates that insulin degludec/insulin aspart translate into sustained glycaemic control with less hypoglycaemia and the potential for a simpler insulin regimen with fewer daily injections. PMID:26568812

Antiobesity Pharmacotherapy for Patients with Type 2 Diabetes: Focus on Long-Term Management

PubMed Central

Jeon, Won Seon

2014-01-01

Type 2 diabetes and obesity have a complex relationship; obesity is linked to insulin resistance, the precursor to type 2 diabetes. The management of obesity is an important method to delay onset of diabetes and improve the glycemic durability of antidiabetic agents. However, insulin and some of the oral hypoglycemic agents used to treat diabetes cause significant weight gain, and it is difficult for patients with diabetes to reduce and maintain their weight by life-style changes alone. Thus, antiobesity medications or bariatric surgery may be a necessary adjunct for certain obese patients with diabetes. In 2012, the U.S. Food and Drug Administration (FDA) approved lorcaserin and phentermine/topiramate extended-release for the management of chronic weight, and approval for naltrexone/bupropion sustained-release as an adjunct to exercise and reduced caloric intake followed in 2014. Liraglutide is pending FDA approval for antiobesity drug. Here we review the efficacy of approved and new promising drugs for the management of obesity. PMID:25559569

Effects of food pattern change and physical exercise on cafeteria diet-induced obesity in female rats.

PubMed

Goularte, Jéferson F; Ferreira, Maria B C; Sanvitto, Gilberto L

2012-10-28

Obesity affects a large number of people around the world and appears to be the result of changes in food intake, eating habits and physical activity levels. Changes in dietary patterns and physical exercise are therefore strongly recommended to treat obesity and its complications. The present study tested the hypothesis that obesity and metabolic changes produced by a cafeteria diet can be prevented with dietary changes and/or physical exercise. A total of fifty-six female Wistar rats underwent one of five treatments: chow diet; cafeteria diet; cafeteria diet followed by a chow diet; cafeteria diet plus exercise; cafeteria diet followed by a chow diet plus exercise. The duration of the experiment was 34 weeks. The cafeteria diet resulted in higher energy intake, weight gain, increased visceral adipose tissue and liver weight, and insulin resistance. The cafeteria diet followed by the chow diet resulted in energy intake, body weight, visceral adipose tissue and liver weight and insulin sensitivity equal to that of the controls. Exercise increased total energy intake at week 34, but produced no changes in the animals' body weight or adipose tissue mass. However, insulin sensitivity in animals subjected to exercise and the diet was similar to that of the controls. The present study found that exposure to palatable food caused obesity and insulin resistance and a diet change was sufficient to prevent cafeteria diet-induced obesity and to maintain insulin sensitivity at normal levels. In addition, exercise resulted in normal insulin sensitivity in obese rats. These results may help to develop new approaches for the treatment of obesity and type 2 diabetes mellitus.

Comparison of repaglinide vs. gliclazide in combination with bedtime NPH insulin in patients with Type 2 diabetes inadequately controlled with oral hypoglycaemic agents.

PubMed

Furlong, N J; Hulme, S A; O'Brien, S V; Hardy, K J

2003-11-01

This open-label randomized controlled clinical trial compared the effect on glycaemic control and weight gain of repaglinide vs. gliclazide combined with bedtime NPH insulin in patients with Type 2 diabetes inadequately controlled with oral hypoglycaemic therapy [HbA1c>7.0% (DCCT aligned assay, normal range 4.6-6.2%)]. Eighty subjects with Type 2 diabetes were randomized to 13 weeks' open-label treatment with repaglinide 4 mg t.i.d. or gliclazide 160 mg b.i.d. in combination with bedtime NPH insulin (initial dose 0.5 units/kg). The fasting blood glucose (FBG) target was < or =6.0 mmol/l. Baseline characteristics were similar for age, sex, weight, BMI, FBG and HbA1c. Glycaemic control improved similarly in both groups-insulin/gliclazide by (mean) 1.0%, from 9.2 to 8.2% (P=0.001) and by 0.9%, from 9.4 to 8.5% in the insulin/repaglinide group (P=0.005) (P=0.83 between groups). Weight gain averaged (mean +/- sem) 4.1 +/- 0.5 and 3.4 +/- 0.4 kg in the insulin/gliclazide and insulin/repaglinide groups, respectively (P<0.0001 for both groups from baseline) (P=0.29 between groups). The mean number of hypoglycaemic episodes experienced per patient was 2.95 +/- 0.82 (insulin/gliclazide) and 2.3 +/- 0.52 (insulin/repaglinide) (P=0.81 between groups). Both treatments were associated with significant improvements in Diabetes Treatment Satisfaction [Diabetes Treatment Satisfaction Questionnaire-potential range 0 (min) to 36 (max)]; in the insulin/gliclazide group, by 4.9 +/- 1.1 points to 33.3 +/- 0.6 (P<0.0001) and by 3.0 +/- 0.9 points to 34.6 +/- 0.4 (P=0.0006) in the insulin/repaglinide group (P=0.29 between groups). Over 13 weeks, both repaglinide and gliclazide, when combined with bedtime NPH insulin produce similar significant improvements in glycaemic control (-1%) and similar weight gain.

Functional silencing is initiated and maintained in immature anti-insulin B cells.

PubMed

Henry, Rachel A; Acevedo-Suárez, Carlos A; Thomas, James W

2009-03-15

Mechanisms of B cell tolerance act during development in the bone marrow and periphery to eliminate or restrict autoreactive clones to prevent autoimmune disease. B cells in the spleens of mice that harbor anti-insulin BCR transgenes (125Tg) are maintained in a functionally silenced or anergic state by endogenous hormone, but it is not clear when and where anergy is induced. An in vitro bone marrow culture system was therefore used to probe whether small protein hormones, a critical class of autoantigens, could interact with the BCR to induce anergy early during B cell development. Upon exposure to insulin, anti-insulin (125Tg) immature B cells show similar hallmarks of anergy as those observed in mature splenic B cells. These include BCR down-regulation, impaired proliferative responses to anti-CD40, and diminished calcium mobilization upon stimulation with BCR-dependent and independent stimuli. Inhibition of calcineurin also results in reduced immature B cell proliferation in a similar manner, suggesting a potential mechanism through which reduced intracellular calcium mobilization may be altering cellular proliferation. Signs of impairment appear after short-term exposure to insulin, which are reversible upon Ag withdrawal. This suggests that a high degree of functional plasticity is maintained at this stage and that constant Ag engagement is required to maintain functional inactivation. These findings indicate that tolerance observed in mature, splenic 125Tg B cells is initiated by insulin in the developing B cell compartment and thus highlight an important therapeutic window for the prevention of insulin autoimmunity.

Evaluating the cost-effectiveness of insulin detemir versus neutral protamine Hagedorn insulin in patients with type 1 or type 2 diabetes in the UK using a short-term modeling approach.

PubMed

Pollock, Richard F; Chubb, Barrie; Valentine, William J; Heller, Simon

2018-01-01

To estimate the short-term cost-effectiveness of insulin detemir (IDet) versus neutral protamine Hagedorn (NPH) insulin based on the incidence of non-severe hypoglycemia and changes in body weight in subjects with type 1 diabetes (T1D) or type 2 diabetes (T2D) in the UK. A model was developed to evaluate cost-effectiveness based on non-severe hypoglycemia, body mass index, and pharmacy costs over 1 year. Published rates of non-severe hypoglycemia were employed in the T1D and T2D analyses, while reduced weight gain with IDet was modeled in the T2D analysis only. Effectiveness was calculated in terms of quality-adjusted life expectancy using published utility scores. Pharmacy costs were captured using published prices and defined daily doses. Costs were expressed in 2016 pounds sterling (GBP). Sensitivity analyses were performed (including probabilistic sensitivity analysis). In T1D, IDet was associated with fewer non-severe hypoglycemic events than NPH insulin (126.7 versus 150.8 events per person-year), leading to an improvement of 0.099 quality-adjusted life years (QALYs). Costs with IDet were GBP 60 higher, yielding an incremental cost-effectiveness ratio (ICER) of GBP 610 per QALY gained. In T2D, mean non-severe hypoglycemic event rates and body weight were lower with IDet than NPH insulin, leading to a total incremental utility of 0.120, accompanied by an annual cost increase of GBP 171, yielding an ICER of GBP 1,422 per QALY gained for IDet versus NPH insulin. Short-term health economic evaluation showed IDet to be a cost-effective alternative to NPH insulin in the UK due to lower rates of non-severe hypoglycemia (T1D and T2D) and reduced weight gain (T2D only).

The Impact of Weight Gain on Motivation, Compliance, and Metabolic Control in Patients with Type 2 Diabetes Mellitus

PubMed Central

Pi-Sunyer, F. Xavier

2010-01-01

Patients with type 2 diabetes, approximately 85% of whom are overweight or obese, often have an increased incidence of cardiovascular disease (CVD) risk factors such as hypertension and dyslipidemia. Both type 2 diabetes and obesity are independent risk factors for CVD. Unfortunately, many therapies aimed at maintaining and improving glucose control are associated with weight gain. Among the older antidiabetes agents, most, including the insulin secretagogues and sensitizers, can lead to weight gain, except for metformin, which is weight-neutral. Among the newer agents, the dipeptidyl peptidase-4 inhibitors generally are weight-neutral in addition to lowering glucose, while the glucagon-like peptide–1 receptor agonists lead to weight reduction. Patients with type 2 diabetes are at an increased risk for both diabetes-and CV-related outcomes, and weight reduction is an important component of diabetes management. Weight gain in patients with type 2 diabetes can contribute to patient frustration and may negatively impact their compliance to therapeutic regimens. The selection of antidiabetes agents that not only improve glucose control but reduce or have a neutral effect on weight with beneficial effects on lipids are ideal options for managing patients with type 2 diabetes. PMID:19820278

Antihyperglycaemic potential of the water-ethanol extract of Kalanchoe crenata (Crassulaceae).

PubMed

Kamgang, René; Mboumi, Rostand Youmbi; Fondjo, Angèle Foyet; Tagne, Michel Archange Fokam; N'dillé, Gabriel Patrice Roland Mengue; Yonkeu, Jeanne Ngogang

2008-01-01

Kalanchoe crenata is a vegetable widely used in Cameroon and largely efficient in the treatment of diabetes mellitus. The effect of the water-ethanol extract of this plant (WEKC) on blood glucose levels was investigated in fasting normal and diet-induced diabetic rats (MACAPOS 1) after a short- and medium-term treatment. Diabetes was induced by submitting Wistar rats to a hypercaloric sucrose diet over 4 months. Six hours after a single oral administration of WEKC, 135 and 200 mg kg(-1) body weight extracts significantly (P < 0.01) reduced the blood glucose levels both in normal and diabetic rats without real dose-dependent effect. During the medium-term treatment, 200 mg kg(-1) WEKC administered daily for 4 weeks significantly reduced blood glucose levels within week 1 (P < 0.05), with a maximum effect at week 4 (-52%, P < 0.01), while maintaining glycaemia within the normal range. All the WEKC-treated diabetic rats exhibited significant (P < 0.01) increase in insulin sensitivity index (K (ITT)) compared with the initial time and to the untreated diabetic animals. Animals treated for 4 weeks exhibited a slight resistance in body-weight gain and decrease in food and water intake. The WEKC activities on all parameters assessed were comparable with the glibenclamide effects. Qualitative phytochemical screening revealed that K. crenata contains terpenoids, tannins, polysaccharids, saponins, flavonoids and alkaloids. The data suggest that K. crenata might contain important chemical components that could induce significant improvement in glucose clearance and/or uptake and resistance to body-weight gain and insulin sensitivity, and could be a potent alternative or complementary therapeutic substance in the control of type 2 diabetes and other insulin-resistant conditions.

Long-term high-fat feeding induces greater fat storage in mice lacking UCP3.

PubMed

Costford, Sheila R; Chaudhry, Shehla N; Crawford, Sean A; Salkhordeh, Mahmoud; Harper, Mary-Ellen

2008-11-01

Uncoupling protein-3 (UCP3) is a mitochondrial inner-membrane protein highly expressed in skeletal muscle. While UCP3's function is still unknown, it has been hypothesized to act as a fatty acid (FA) anion exporter, protecting mitochondria against lipid peroxidation and/or facilitating FA oxidation. The aim of this study was to determine the effects of long-term feeding of a 45% fat diet on whole body indicators of muscle metabolism in congenic C57BL/6 mice that were either lacking UCP3 (Ucp3(-/-)) or had a transgenically induced approximately twofold increase in UCP3 levels (UCP3tg). Mice were fed the high-fat (HF) diet for a period of either 4 or 8 mo immediately following weaning. After long-term HF feeding, UCP3tg mice weighed an average of 15% less than wild-type mice (P < 0.05) and were 20% less metabolically efficient than both wild-type and Ucp3(-/-) mice (P < 0.01). Additionally, wild-type mice had 21% lower, whereas UCP3tg mice had 36% lower, levels of adiposity compared with Ucp3(-/-) mice (P < 0.05 and P < 0.001, respectively), indicating a protective effect of UCP3 against fat gain. No differences in whole body oxygen consumption were detected following long-term HF feeding. Glucose and insulin tolerance tests revealed that both the UCP3tg and Ucp3(-/-) mice were more glucose tolerant and insulin sensitive compared with wild-type mice after short-term HF feeding, but this protection was not maintained in the long term. Findings indicate that UCP3 is involved in protection from fat gain induced by long-term HF feeding, but not in protection from insulin resistance.

Maternal insulin resistance, triglycerides and cord blood insulin in relation to post-natal weight trajectories and body composition in the offspring up to 2 years.

PubMed

Brunner, S; Schmid, D; Hüttinger, K; Much, D; Heimberg, E; Sedlmeier, E-M; Brüderl, M; Kratzsch, J; Bader, B L; Amann-Gassner, U; Hauner, H

2013-12-01

The intrauterine metabolic environment might have a programming effect on offspring body composition. We aimed to explore associations of maternal variables of glucose and lipid metabolism during pregnancy, as well as cord blood insulin, with infant growth and body composition up to 2 years post-partum. Data of pregnant women and their infants came from a randomized controlled trial designed to investigate the impact of nutritional fatty acids on adipose tissue development in the offspring. Of the 208 pregnant women enrolled, 118 infants were examined at 2 years. In the present analysis, maternal fasting plasma insulin, homeostasis model assessment of insulin resistance and serum triglycerides measured during pregnancy, as well as insulin in umbilical cord plasma, were related to infant growth and body composition assessed by skinfold thickness measurements and abdominal ultrasonography up to 2 years of age. Maternal homeostasis model assessment of insulin resistance at the 32nd week of gestation was significantly inversely associated with infant lean body mass at birth, whereas the change in serum triglycerides during pregnancy was positively associated with ponderal index at 4 months, but not at later time points. Cord plasma insulin correlated positively with birthweight and neonatal fat mass and was inversely associated with body weight gain up to 2 years after multiple adjustments. Subsequent stratification by gender revealed that this relationship with weight gain was stronger, and significant only in girls. Cord blood insulin is inversely associated with subsequent infant weight gain up to 2 years and this seems to be more pronounced in girls. © 2013 The Authors. Diabetic Medicine © 2013 Diabetes UK.

Three-year efficacy of complex insulin regimens in type 2 diabetes.

PubMed

Holman, Rury R; Farmer, Andrew J; Davies, Melanie J; Levy, Jonathan C; Darbyshire, Julie L; Keenan, Joanne F; Paul, Sanjoy K

2009-10-29

Evidence supporting the addition of specific insulin regimens to oral therapy in patients with type 2 diabetes mellitus is limited. In this 3-year open-label, multicenter trial, we evaluated 708 patients who had suboptimal glycated hemoglobin levels while taking metformin and sulfonylurea therapy. Patients were randomly assigned to receive biphasic insulin aspart twice daily, prandial insulin aspart three times daily, or basal insulin detemir once daily (twice if required). Sulfonylurea therapy was replaced by a second type of insulin if hyperglycemia became unacceptable during the first year of the study or subsequently if glycated hemoglobin levels were more than 6.5%. Outcome measures were glycated hemoglobin levels, the proportion of patients with a glycated hemoglobin level of 6.5% or less, the rate of hypoglycemia, and weight gain. Median glycated hemoglobin levels were similar for patients receiving biphasic (7.1%), prandial (6.8%), and basal (6.9%) insulin-based regimens (P=0.28). However, fewer patients had a level of 6.5% or less in the biphasic group (31.9%) than in the prandial group (44.7%, P=0.006) or in the basal group (43.2%, P=0.03), with 67.7%, 73.6%, and 81.6%, respectively, taking a second type of insulin (P=0.002). [corrected] Median rates of hypoglycemia per patient per year were lowest in the basal group (1.7), higher in the biphasic group (3.0), and highest in the prandial group (5.7) (P<0.001 for the overall comparison). The mean weight gain was higher in the prandial group than in either the biphasic group or the basal group. Other adverse event rates were similar in the three groups. Patients who added a basal or prandial insulin-based regimen to oral therapy had better glycated hemoglobin control than patients who added a biphasic insulin-based regimen. Fewer hypoglycemic episodes and less weight gain occurred in patients adding basal insulin. (Current Controlled Trials number, ISRCTN51125379.) 2009 Massachusetts Medical Society

Hyperthyroidism impairs pancreatic beta cell adaptations to late pregnancy and maternal liporegulation in the rat.

PubMed

Holness, M J; Greenwood, G K; Smith, N D; Sugden, M C

2005-11-01

Hyperthyroidism modifies lipid dynamics (increased oxidation), impairs insulin action and can suppress insulin secretion. We therefore examined the impact of hyperthyroidism on the relationship between glucose-stimulated insulin secretion (GSIS) and insulin action, using late pregnancy as a model of physiological insulin resistance that is associated with compensatory insulin hypersecretion to maintain glucose tolerance. Our aim was to examine whether hyperthyroidism compromises the regulation of insulin secretion and the ability of insulin to modulate circulating lipid concentrations in late pregnancy. Hyperthyroidism was induced by tri-iodothyronine (T(3)) administration from day 17 to 19 of pregnancy. GSIS was assessed during an IVGTT and during hyperglycaemic clamps in vivo and in vitro, using step-up and -down islet perifusions. Hyperthyroidism in pregnancy elevated the glucose threshold for GSIS and impaired GSIS at low and high glucose concentrations in islet perifusions. In the intact animal, insulin secretion (after bolus glucose) was more rapidly curtailed following removal of the glucose stimulus to secretion. In contrast, GSIS was maintained during protracted hyperglycaemia (hyperglycaemic clamps) in the hyperthyroid pregnant state in vivo. Hyperthyroidism in vivo during late pregnancy blunts GSIS in subsequently isolated and perifused islets at low and high glucose concentrations. It also adversely affects GSIS under conditions of an acute glucose challenge in vivo. In contrast, GSIS is maintained during sustained hyperglycaemia in vivo, suggesting that in vivo factors can rescue GSIS. The ability of insulin to suppress systemic lipid levels during hyperglycaemic clamps was impaired. We therefore suggest that higher circulating lipids may preserve GSIS under conditions of sustained hyperglycaemia in the hyperthyroid pregnancy.

[Cyanidin-3-glucoside attenuates body weight gain, serum lipid concentrations and insulin resistance in high-fat diet-induced obese rats].

PubMed

Yu, Ren-Qiang; Wu, Xiao-You; Zhou, Xiang; Zhu, Jing; Ma, Lu-Yi

2014-05-01

Cyanidin-3-glucoside (C3G) is the main active ingredient of anthocyanidin. This study aimed to evaluate the effects of C3G on body weight gain, visceral adiposity, lipid profiles and insulin resistance in high-fat diet-induced obese rats. Thirty male Sprague-Dawley rats were randomly divided into a control group (n=8) and a high fat diet group (n=22), and were fed with standard diet or high fat diet. Five weeks later, 17 high-fat diet-induced obese rats were randomly given C3G [100 mg/(kg·d)] or normal saline via intragastric administration for 5 weeks. Five weeks later, body weight, visceral adiposity and food intake were measured. Blood samples were collected for detecting fasting glucose, serum insulin, lipid profiles and adiponectin. Insulin resistance index, atherosclerosis index and average feed efficiency ratio were calculated. C3G supplementation markedly decreased body weight, visceral adiposity, average feed efficiency ratio, triglyceride, total cholesterol, low density lipoprotein cholesterol, fasting glucose, serum insulin, insulin resistance index and atherosclerosis index in high-fat diet-induced obese rats. C3G supplementation normalized serum adiponectin and high density lipoprotein cholesterol levels in high-fat diet-induced obese rats. Cyanidin-3-glucoside can reduce body weight gain, and attenuate obesity-associated dyslipidemia and insulin resistance in high-fat diet-fed rats via up-regulating serum adiponectin level.

Alterations in glucose and protein metabolism in animals subjected to simulated microgravity

NASA Technical Reports Server (NTRS)

Mondon, C. E.; Rodnick, K. J.; Azhar, S.; Reaven, G. M.; Dolkas, C. B.

1992-01-01

Reduction of physical activity due to disease or environmental restraints, such as total bed rest or exposure to spaceflight, leads to atrophy of skeletal muscle and is frequently accompanied by alterations in food intake and the concentration of metabolic regulatory hormones such as insulin. Hindlimb suspension of laboratory rats, as a model for microgravity, also shows marked atrophy of gravity-dependent muscles along with a reduced gain in body weight. Suspended rats exhibit enhanced sensitivity to insulin-induced glucose uptake when compared with normal control rats and resistance to insulin action when compared with control rats matched similarly for reduced body weight gain. These changes are accompanied by decreased insulin binding and tyrosine kinase activity in soleus but not plantaris muscle, unchanged glucose uptake by perfused hindlimb and decreased sensitivity but not responsiveness to insulin-induced suppression of net proteolysis in hindlimb skeletal muscle. These findings suggest that loss of insulin sensitivity during muscle atrophy is associated with decreased insulin binding and tyrosine kinase activity in atrophied soleus muscle along with decreased sensitivity to the effects of insulin on suppressing net protein breakdown but not on enhancing glucose uptake by perfused hindlimb.

Alterations in glucose and protein metabolism in animals subjected to simulated microgravity

NASA Astrophysics Data System (ADS)

Mondon, C. E.; Rodnick, K. J.; Dolkas, C. B.; Azhar, S.; Reaven, G. M.

1992-09-01

Reduction of physical activity due to disease or environmental restraints, such as total bed rest or exposure to spaceflight, leads to atrophy of skeletal muscle and is frequently accompanied by alterations in food intake and the concentration of metabolic regulatory hormones such as insulin. Hindlimb suspension of laboratory rats, as a model for microgravity, also shows marked atrophy of gravity dependent muscles along with a reduced gain in body weight. Suspended rats exhibit enhanced sensitivity to insulin-induced glucose uptake when compared with normal control rats and resistance to insulin action when compared with control rats matched similarly for reduced body weight gain. These changes are accompanied by decreased insulin binding and tyrosine kinase activity in soleus but not plantaris muscle, unchanged glucose uptake by perfused hindlimb and decreased sensitivity but not responsiveness to insulin-induced suppression of net proteolysis in hindlimb skeletal muscle. These findings suggest that loss of insulin sensitivity during muscle atrophy is associated with decreased insulin binding and tyrosine kinase activity in atrophied soleus muscle along with decreased sensitivity to the effects of insulin on suppressing net protein breakdown but not on enhancing glucose uptake by perfused hindlimb.

Cost-Effectiveness of Insulin Degludec Versus Insulin Glargine U100 in Patients with Type 1 and Type 2 Diabetes Mellitus in Serbia.

PubMed

Lalić, Nebojša; Russel-Szymczyk, Monika; Culic, Marina; Tikkanen, Christian Klyver; Chubb, Barrie

2018-04-26

This study investigates the cost-effectiveness of insulin degludec versus insulin glargine U100 in patients with type 1 and type 2 diabetes mellitus in Serbia. A cost-utility analysis, implementing a simple short-term model, was used to compare treatment costs and outcomes with degludec versus glargine U100 in patients with type 1 (T1DM) and type 2 diabetes (T2DM). Cost-effectiveness was analysed in a 1-year setting, based on data from clinical trials. Costs were estimated from the healthcare payer perspective, the Serbian Health Insurance Fund (RFZO). The outcome measure was the incremental cost-effectiveness ratio (ICER) or cost per quality-adjusted life-year (QALY) gained. Degludec is highly cost-effective compared with glargine U100 for people with T1DM and T2DM in Serbia. The ICERs are estimated at 417,586 RSD/QALY gained in T1DM, 558,811 RSD/QALY gained in T2DM on basal oral therapy (T2DM BOT ) and 1,200,141 RSD/QALY gained in T2DM on basal-bolus therapy (T2DM B/B ). All ICERs fall below the commonly accepted thresholds for cost-effectiveness in Serbia (1,785,642 RSD/QALY gained). In all three patient groups, insulin costs are higher with degludec than with glargine U100, but these costs are partially offset by savings from a lower daily insulin dose in T1DM and T2DM BOT , a reduction in hypoglycaemic events in all three patient groups and reduced costs of SMBG testing in the T2DM groups with degludec versus glargine U100. Degludec is a cost-effective alternative to glargine U100 for patients with T1DM and T2DM in Serbia. Degludec may particularly benefit those suffering from hypoglycaemia or where the patient would benefit from the option of flexible dosing. Novo Nordisk.

Long term rebaudioside A treatment does not alter circadian activity rhythms, adiposity, or insulin action in male mice

PubMed Central

Reynolds, Thomas H.; Soriano, Rachelle A.; Obadi, Obadi A.; Murkland, Stanley; Possidente, Bernard

2017-01-01

Obesity is a major public health problem that is highly associated with insulin resistance and type 2 diabetes, two conditions associated with circadian disruption. To date, dieting is one of the only interventions that result in substantial weight loss, but restricting caloric intake is difficult to maintain long-term. The use of artificial sweeteners, particularly in individuals that consume sugar sweetened beverages (energy drinks, soda), can reduce caloric intake and possibly facilitate weight loss. The purpose of the present study was to examine the effects of the artificial sweetener, rebaudioside A (Reb-A), on circadian rhythms, in vivo insulin action, and the susceptibility to diet-induced obesity. Six month old male C57BL/6 mice were assigned to a control or Reb-A (0.1% Reb-A supplemented drinking water) group for six months. Circadian wheel running rhythms, body weight, caloric intake, insulin action, and susceptibility to diet-induced obesity were assessed. Time of peak physical activity under a 12:12 light-dark (LD) cycle, mean activity levels, and circadian period in constant dark were not significantly different in mice that consumed Reb-A supplemented water compared to normal drinking water, indicating that circadian rhythms and biological clock function were unaltered. Although wheel running significantly reduced body weight in both Reb-A and control mice (P = 0.0001), consuming Reb-A supplemented water did not alter the changes in body weight following wheel running (P = 0.916). In vivo insulin action, as assessed by glucose, insulin, and pyruvate tolerance tests, was not different between mice that consumed Reb-A treated water compared to normal drinking water. Finally, Reb-A does not appear to change the susceptibility to diet-induced obesity as both groups of mice gained similar amounts of body weight when placed on a high fat diet. Our results indicate that consuming Reb-A supplemented water does not promote circadian disruption, insulin resistance, or obesity. PMID:28475596

Long term rebaudioside A treatment does not alter circadian activity rhythms, adiposity, or insulin action in male mice.

PubMed

Reynolds, Thomas H; Soriano, Rachelle A; Obadi, Obadi A; Murkland, Stanley; Possidente, Bernard

2017-01-01

Obesity is a major public health problem that is highly associated with insulin resistance and type 2 diabetes, two conditions associated with circadian disruption. To date, dieting is one of the only interventions that result in substantial weight loss, but restricting caloric intake is difficult to maintain long-term. The use of artificial sweeteners, particularly in individuals that consume sugar sweetened beverages (energy drinks, soda), can reduce caloric intake and possibly facilitate weight loss. The purpose of the present study was to examine the effects of the artificial sweetener, rebaudioside A (Reb-A), on circadian rhythms, in vivo insulin action, and the susceptibility to diet-induced obesity. Six month old male C57BL/6 mice were assigned to a control or Reb-A (0.1% Reb-A supplemented drinking water) group for six months. Circadian wheel running rhythms, body weight, caloric intake, insulin action, and susceptibility to diet-induced obesity were assessed. Time of peak physical activity under a 12:12 light-dark (LD) cycle, mean activity levels, and circadian period in constant dark were not significantly different in mice that consumed Reb-A supplemented water compared to normal drinking water, indicating that circadian rhythms and biological clock function were unaltered. Although wheel running significantly reduced body weight in both Reb-A and control mice (P = 0.0001), consuming Reb-A supplemented water did not alter the changes in body weight following wheel running (P = 0.916). In vivo insulin action, as assessed by glucose, insulin, and pyruvate tolerance tests, was not different between mice that consumed Reb-A treated water compared to normal drinking water. Finally, Reb-A does not appear to change the susceptibility to diet-induced obesity as both groups of mice gained similar amounts of body weight when placed on a high fat diet. Our results indicate that consuming Reb-A supplemented water does not promote circadian disruption, insulin resistance, or obesity.

Insulin initiation in primary care for patients with type 2 diabetes: 3-year follow-up study.

PubMed

Dale, Jeremy; Martin, Steven; Gadsby, Roger

2010-07-01

To evaluate the 3-year impact of initiating basal insulin on glycaemic control (HbA1c) and weight gain in patients with poorly controlled type 2 diabetes registered with UK general practices that volunteered to participate in an insulin initiation training programme. Audit utilising data collected from practice record systems, which included data at baseline, 3, 6 months and subsequent six-monthly intervals post-insulin initiation for up to 10 patients per participating practice. Of 115 eligible practices, 55 (47.8%) contributed data on a total of 516 patients. The mean improvement in HbA1c levels in the first 6 months was 1.4% (range -3.8% to 8.2%, median=1.40%). Thereafter, there was no overall change in HbA1c levels, although the change for individual patients ranged from -4.90% to +7.50%. At 36 months, 141 (41%) patients for whom data were provided had achieved the pre-2006/2007 UK Quality and Outcomes Framework (QOF) target of 7.4% or less, including 98 (29%) who had achieved an HbA1c of 7% or less. Patients who achieved target had a lower HbA1c at baseline (mean 9.1% compared to 9.7%; p<0.001); had a lower weight at 36 months (mean 88.0kg compared to 93.5kg; p=0.05); were more likely to be on basal insulin alone (88, 47.1% compared to 46, 34.6%; p<0.05); and were slightly older (mean 64.5 years compared to 61.7 years; p<0.05). Attending an insulin initiation training programme may successfully prepare primary healthcare professionals to initiate insulin therapy as part of everyday practice for patients with poorly controlled type 2 diabetes. The impact on glycaemic control is maintained over a 3-year period. Although intensification of treatment occurred during this period, the findings suggest scope for further intensification of insulin therapy in order to improve on the glycaemic control achieved during the first 6 months post-insulin initiation.

Cerebral Blood Flow and Glucose Metabolism in Appetite-Related Brain Regions in Type 1 Diabetic Patients After Treatment With Insulin Detemir and NPH Insulin

PubMed Central

van Golen, Larissa W.; IJzerman, Richard G.; Huisman, Marc C.; Hensbergen, Jolanda F.; Hoogma, Roel P.; Drent, Madeleine L.; Lammertsma, Adriaan A.; Diamant, Michaela

2013-01-01

OBJECTIVE To test the hypothesis that insulin detemir, which is associated with less weight gain than other basal insulin formulations, exerts its weight-modulating effects by acting on brain regions involved in appetite regulation, as represented by altered cerebral blood flow (CBF) or cerebral glucose metabolism (CMRglu). RESEARCH DESIGN AND METHODS Twenty-eight male type 1 diabetic patients (age 36.9 ± 9.7 years, BMI 24.9 ± 2.7 kg/m2, A1C 7.5 ± 0.6%) successfully completed a randomized crossover study, consisting of two periods of 12-week treatment with either insulin detemir or NPH insulin, both in combination with prandial insulin aspart. After each treatment period, patients underwent positron emission tomography scans to measure regional CBF and CMRglu. RESULTS After 12 weeks, A1C, daily insulin doses, fasting insulin, and blood glucose levels were similar between treatments. Insulin detemir resulted in body weight loss, whereas NPH insulin induced weight gain (between-treatment difference 1.3 kg; P = 0.02). After treatment with insulin detemir relative to NPH insulin, CBF was higher in brain regions involved in appetite regulation, whereas no significant difference in CMRglu was observed. CONCLUSIONS Treatment with insulin detemir versus NPH insulin resulted in weight loss, paralleled by increased CBF in appetite-related brain regions in the resting state, in men with well-controlled type 1 diabetes. These findings lend support to the hypothesis that a differential effect on the brain may contribute to the consistently observed weight-sparing effect of insulin detemir. PMID:24130356

Diet-genotype interactions in the development of the obese, insulin-resistant phenotype of C57BL/6J mice lacking melanocortin-3 or -4 receptors.

PubMed

Sutton, Gregory M; Trevaskis, James L; Hulver, Matthew W; McMillan, Ryan P; Markward, Nathan J; Babin, M Josephine; Meyer, Emily A; Butler, Andrew A

2006-05-01

Loss of brain melanocortin receptors (Mc3rKO and Mc4rKO) causes increased adiposity and exacerbates diet-induced obesity (DIO). Little is known about how Mc3r or Mc4r genotype, diet, and obesity affect insulin sensitivity. Insulin resistance, assessed by insulin and glucose tolerance tests, Ser(307) phosphorylation of insulin receptor substrate 1, and activation of protein kinase B, was examined in control and DIO wild-type (WT), Mc3rKO and Mc4rKO C57BL/6J mice. Mc4rKO mice were hyperphagic and had increased metabolic efficiency (weight gain per kilojoule consumed) relative to WT; both parameters increased further on high-fat diet. Obesity of Mc3rKO was more dependent on fat intake, involving increased metabolic efficiency. Fat mass of DIO Mc3rKO and Mc4rKO was similar, although Mc4rKO gained weight more rapidly. Mc4rKO develop hepatic insulin resistance and severe hepatic steatosis with obesity, independent of diet. DIO caused further deterioration of insulin action in Mc4rKO of either sex and, in male Mc3rKO, compared with controls, associated with increased fasting insulin, severe glucose intolerance, and reduced insulin signaling in muscle and adipose tissue. DIO female Mc3rKO exhibited very modest perturbations in glucose metabolism and insulin sensitivity. Consistent with previous data suggesting impaired fat oxidation, both Mc3rKO and Mc4rKO had reduced muscle oxidative metabolism, a risk factor for weight gain and insulin resistance. Energy expenditure was, however, increased in Mc4rKO compared with Mc3rKO and controls, perhaps due to hyperphagia and metabolic costs associated with rapid growth. In summary, DIO affects insulin sensitivity more severely in Mc4rKO compared with Mc3rKO, perhaps due to a more positive energy balance.

Hyperandrogenemia Induced by Letrozole Treatment of Pubertal Female Mice Results in Hyperinsulinemia Prior to Weight Gain and Insulin Resistance.

PubMed

Skarra, Danalea V; Hernández-Carretero, Angelina; Rivera, Alissa J; Anvar, Arya R; Thackray, Varykina G

2017-09-01

Women with polycystic ovary syndrome (PCOS) diagnosed with hyperandrogenism and ovulatory dysfunction have an increased risk of developing metabolic disorders, including type 2 diabetes and cardiovascular disease. We previously developed a model that uses letrozole to elevate endogenous testosterone levels in female mice. This model has hallmarks of PCOS, including hyperandrogenism, anovulation, and polycystic ovaries, as well as increased abdominal adiposity and glucose intolerance. In the current study, we further characterized the metabolic dysfunction that occurs after letrozole treatment to determine whether this model represents a PCOS-like metabolic phenotype. We focused on whether letrozole treatment results in altered pancreatic or liver function as well as insulin resistance. We also investigated whether hyperinsulinemia occurs secondary to weight gain and insulin resistance in this model or if it can occur independently. Our study demonstrated that letrozole-treated mice developed hyperinsulinemia after 1 week of treatment and without evidence of insulin resistance. After 2 weeks of letrozole treatment, mice became significantly heavier than placebo mice, demonstrating that weight gain was not required to develop hyperinsulinemia. After 5 weeks of letrozole treatment, mice exhibited blunted glucose-stimulated insulin secretion, insulin resistance, and impaired insulin-induced phosphorylation of AKT in skeletal muscle. Moreover, letrozole-treated mice exhibited dyslipidemia after 5 weeks of treatment but no evidence of hepatic disease. Our study demonstrated that the letrozole-induced PCOS mouse model exhibits multiple features of the metabolic dysregulation observed in obese, hyperandrogenic women with PCOS. This model will be useful for mechanistic studies investigating how hyperandrogenemia affects metabolism in females. Copyright © 2017 Endocrine Society.

Lifecourse Childhood Adiposity Trajectories Associated With Adolescent Insulin Resistance

PubMed Central

Huang, Rae-Chi; de Klerk, Nicholas H.; Smith, Anne; Kendall, Garth E.; Landau, Louis I.; Mori, Trevor A.; Newnham, John P.; Stanley, Fiona J.; Oddy, Wendy H.; Hands, Beth; Beilin, Lawrence J.

2011-01-01

OBJECTIVE In light of the obesity epidemic, we aimed to characterize novel childhood adiposity trajectories from birth to age 14 years and to determine their relation to adolescent insulin resistance. RESEARCH DESIGN AND METHODS A total of 1,197 Australian children with cardiovascular/metabolic profiling at age 14 years were studied serially from birth to age 14 years. Semiparametric mixture modeling was applied to anthropometric data over eight time points to generate adiposity trajectories of z scores (weight-for-height and BMI). Fasting insulin and homeostasis model assessment of insulin resistance (HOMA-IR) were compared at age 14 years between adiposity trajectories. RESULTS Seven adiposity trajectories were identified. Three (two rising and one chronic high adiposity) trajectories comprised 32% of the population and were associated with significantly higher fasting insulin and HOMA-IR compared with a reference trajectory group (with longitudinal adiposity z scores of approximately zero). There was a significant sex by trajectory group interaction (P < 0.001). Girls within a rising trajectory from low to moderate adiposity did not show increased insulin resistance. Maternal obesity, excessive weight gain during pregnancy, and gestational diabetes were more prevalent in the chronic high adiposity trajectory. CONCLUSIONS A range of childhood adiposity trajectories exist. The greatest insulin resistance at age 14 years is seen in those with increasing trajectories regardless of birth weight and in high birth weight infants whose adiposity remains high. Public health professionals should urgently target both excessive weight gain in early childhood across all birth weights and maternal obesity and excessive weight gain during pregnancy. PMID:21378216

Glucose-stimulated insulin response in pregnant sheep following acute suppression of plasma non-esterified fatty acid concentrations

PubMed Central

Regnault, Timothy RH; Oddy, Hutton V; Nancarrow, Colin; Sriskandarajah, Nadarajah; Scaramuzzi, Rex J

2004-01-01

Background Elevated non-esterified fatty acids (NEFA) concentrations in non-pregnant animals have been reported to decrease pancreatic responsiveness. As ovine gestation advances, maternal insulin concentrations fall and NEFA concentrations increase. Experiments were designed to examine if the pregnancy-associated rise in NEFA concentration is associated with a reduced pancreatic sensitivity to glucose in vivo. We investigated the possible relationship of NEFA concentrations in regulating maternal insulin concentrations during ovine pregnancy at three physiological states, non-pregnant, non-lactating (NPNL), 105 and 135 days gestational age (dGA, term 147+/- 3 days). Methods The plasma concentrations of insulin, growth hormone (GH) and ovine placental lactogen (oPL) were determined by double antibody radioimmunoassay. Insulin responsiveness to glucose was measured using bolus injection and hyperglycaemic clamp techniques in 15 non-pregnant, non-lactating ewes and in nine pregnant ewes at 105 dGA and near term at 135 dGA. Plasma samples were also collected for hormone determination. In addition to bolus injection glucose and insulin Area Under Curve calculations, the Mean Plasma Glucose Increment, Glucose Infusion Rate and Mean Plasma Insulin Increment and Area Under Curve were determined for the hyperglycaemic clamp procedures. Statistical analysis of data was conducted with Students t-tests, repeated measures ANOVA and 2-way ANOVA. Results Maternal growth hormone, placental lactogen and NEFA concentrations increased, while basal glucose and insulin concentrations declined with advancing gestation. At 135 dGA following bolus glucose injections, peak insulin concentrations and insulin area under curve (AUC) profiles were significantly reduced in pregnant ewes compared with NPNL control ewes (p < 0.001 and P < 0.001, respectively). In hyperglycaemic clamp studies, while maintaining glucose levels not different from NPNL ewes, pregnant ewes displayed significantly reduced insulin responses and a maintained depressed insulin secretion. In NPNL ewes, 105 and 135 dGA ewes, the Glucose Infusion Rate (GIR) was constant at approximately 5.8 mg glucose/kg/min during the last 40 minutes of the hyperglycaemic clamp and the Mean Plasma Insulin Increment (MPII) was only significantly (p < 0.001) greater in NPNL ewes. Following the clamp, NEFA concentrations were reduced by approximately 60% of pre-clamp levels in all groups, though a blunted and suppressed insulin response was maintained in 105 and 135 dGA ewes. Conclusions Results suggest that despite an acute suppression of circulating NEFA concentrations during pregnancy, the associated steroids and hormones of pregnancy and possibly NEFA metabolism, may act to maintain a reduced insulin output, thereby sparing glucose for non-insulin dependent placental uptake and ultimately, fetal requirements. PMID:15352999

Adjunct therapy for type 1 diabetes mellitus.

PubMed

Lebovitz, Harold E

2010-06-01

Insulin replacement therapy in type 1 diabetes mellitus (T1DM) is nonphysiologic. Hyperinsulinemia is generated in the periphery to achieve normal insulin concentrations in the liver. This mismatch results in increased hypoglycemia, increased food intake with weight gain, and insufficient regulation of postprandial glucose excursions. Islet amyloid polypeptide is a hormone synthesized in pancreatic beta cells and cosecreted with insulin. Circulating islet amyloid polypeptide binds to receptors located in the hindbrain and increases satiety, delays gastric emptying and suppresses glucagon secretion. Thus, islet amyloid polypeptide complements the effects of insulin. T1DM is a state of both islet amyloid polypeptide and insulin deficiency. Pramlintide, a synthetic analog of islet amyloid polypeptide, can replace this hormone in patients with T1DM. When administered as adjunctive therapy to such patients treated with insulin, pramlintide decreases food intake and causes weight loss. Pramlintide therapy is also associated with suppression of glucagon secretion and delayed gastric emptying, both of which decrease postprandial plasma glucose excursions. Pramlintide therapy improves glycemic control and lessens weight gain. Agents that decrease intestinal carbohydrate digestion (alpha-glucosidase inhibitors) or decrease insulin resistance (metformin) might be alternative adjunctive therapies in T1DM, though its benefits are marginally supported by clinical data.

Reversal of endothelial dysfunction in aorta of streptozotocin-nicotinamide-induced type-2 diabetic rats by S-Allylcysteine.

PubMed

Brahmanaidu, Parim; Uddandrao, V V Sathibabu; Sasikumar, Vadivukkarasi; Naik, Ramavat Ravindar; Pothani, Suresh; Begum, Mustapha Sabana; Rajeshkumar, M Prasanna; Varatharaju, Chandrasekar; Meriga, Balaji; Rameshreddy, P; Kalaivani, A; Saravanan, Ganapathy

2017-08-01

Dietary measures and plant-based therapies as prescribed by native systems of medicine have gained attraction among diabetics with claims of efficacy. The present study investigated the effects of S-Allylcysteine (SAC) on body weight gain, glucose, insulin, insulin resistance, and nitric oxide synthase in plasma and argininosuccinate synthase (AS) and argininosuccinate lyase (ASL), lipid peroxides and antioxidant enzymes in aorta of control and streptozotocin-nicotinamide (STZ-NA)-induced diabetic rats. Changes in body weight, glucose, insulin, insulin resistance, and antioxidant profiles of aorta and mRNA expressions of nitric oxide synthase, AS, and ASL were observed in experimental rats. SAC (150 mg/kg b.w) showed its therapeutic effects similar to gliclazide in decreasing glucose, insulin resistance, lipid peroxidation, and increasing body weight; insulin, antioxidant enzymes, and mRNA levels of nitric oxide synthase, argininosuccinate synthase, and argininosuccinate lyase genes in STZ-NA rats. Histopathologic studies also revealed the protective nature of SAC on aorta. In conclusion, garlic and its constituents mediate the anti-diabetic potential through mitigating hyperglycemic status, changing insulin resistance by alleviating endothelial dysregulation in both plasma and tissues.

Female rats selectively bred for high intrinsic aerobic fitness are protected from ovariectomy-associated metabolic dysfunction

PubMed Central

Padilla, Jaume; Park, Young-Min; Welly, Rebecca J.; Scroggins, Rebecca J.; Britton, Steven L.; Koch, Lauren G.; Jenkins, Nathan T.; Crissey, Jacqueline M.; Zidon, Terese; Morris, E. Matthew; Meers, Grace M. E.; Thyfault, John P.

2015-01-01

Ovariectomized rodents model human menopause in that they rapidly gain weight, reduce spontaneous physical activity (SPA), and develop metabolic dysfunction, including insulin resistance. How contrasting aerobic fitness levels impacts ovariectomy (OVX)-associated metabolic dysfunction is not known. Female rats selectively bred for high and low intrinsic aerobic fitness [high-capacity runners (HCR) and low-capacity runners (LCR), respectively] were maintained under sedentary conditions for 39 wk. Midway through the observation period, OVX or sham (SHM) operations were performed providing HCR-SHM, HCR-OVX, LCR-SHM, and LCR-OVX groups. Glucose tolerance, energy expenditure, and SPA were measured before and 4 wk after surgery, while body composition via dual-energy X-ray absorptiometry and adipose tissue distribution, brown adipose tissue (BAT), and skeletal muscle phenotype, hepatic lipid content, insulin resistance via homeostatic assessment model of insulin resistance and AdipoIR, and blood lipids were assessed at death. Remarkably, HCR were protected from OVX-associated increases in adiposity and insulin resistance, observed only in LCR. HCR rats were ∼30% smaller, had ∼70% greater spontaneous physical activity (SPA), consumed ∼10% more relative energy, had greater skeletal muscle proliferator-activated receptor coactivator 1-alpha, and ∼40% more BAT. OVX did not increase energy intake and reduced SPA to the same extent in both HCR and LCR. LCR were particularly affected by an OVX-associated reduction in resting energy expenditure and experienced a reduction in relative BAT; resting energy expenditure correlated positively with BAT across all animals (r = 0.6; P < 0.001). In conclusion, despite reduced SPA following OVX, high intrinsic aerobic fitness protects against OVX-associated increases in adiposity and insulin resistance. The mechanism may involve preservation of resting energy expenditure. PMID:25608751

Development and in vivo evaluation of an oral insulin-PEG delivery system.

PubMed

Calceti, P; Salmaso, S; Walker, G; Bernkop-Schnürch, A

2004-07-01

Insulin-monomethoxypoly(ethylene glycol) derivatives were obtained by preparation of mono- and di-terbutyl carbonate insulin derivatives, reaction of available protein amino groups with activated 750 Da PEG and, finally, amino group de-protection. This procedure allowed for obtaining high yield of insulin-1PEG and insulin-2PEG. In vivo studies carried out by subcutaneous injection into diabetic mice demonstrated that the two bioconjugates maintained the native biological activity. In vitro, PEGylation was found to enhance the hormone stability towards proteases. After 1 h incubation with elastase, native insulin, insulin-1PEG and insulin-2PEG undergo about 70, 30 and 10% degradation, respectively, while in the presence of pepsin protein degradation was 100, 70 and 50%, respectively. The attachment of low molecular weight PEG did not significantly (P >0.05) alter insulin permeation behavior across the intestinal mucosa. Insulin-1PEG was formulated into mucoadhesive tablets constituted by the thiolated polymer poly(acrylic acid)-cysteine. The therapeutic agent was sustained released from these tablets within 5 h. In vivo, by oral administration to diabetic mice, the glucose levels were found to decrease of about 40% since the third hour from administration and the biological activity was maintained up to 30 h. According to these results, the combination of PEGylated insulin with a thiolated polymer used as drug carrier matrix might be a promising strategy for oral insulin administration.

A 24-week, prospective, randomized, open-label, treat-to-target pilot study of obese type 2 diabetes patients with severe insulin resistance to assess the addition of exenatide on the efficacy of u-500 regular insulin plus metformin.

PubMed

Distiller, Larry A; Nortje, Hendrik; Wellmann, Holger; Amod, Aslam; Lombard, Landman

2014-11-01

To compare the efficacy of 500 U/mL (U-500) regular insulin + metformin with U-500 regular insulin + metformin + exenatide in improving glycemic control in patients with severely insulin-resistant type 2 diabetes mellitus (T2DM). Thirty patients with T2DM and severe insulin resistance were screened, and 28 were randomized to regular insulin U-500 + metformin or the GLP-1 analog exenatide, U-500, and metformin. Glycated hemoglobin (HbA1c) levels, body weight, and insulin doses were documented at baseline and at 3 and 6 months. The number and severity hypoglycemic episodes were noted. There were 7 males and 7 females in each group (U-500 + metformin and U-500 + metformin + exenatide). Overall, U-500 insulin + metformin, either alone or with the addition of exenatide, resulted in a significant improvement in HbA1c in both groups, with no significant difference between the 2 groups. There was no meaningful weight change in those utilizing exenatide. Those on U-500 insulin and metformin alone had a tendency toward some weight gain. No severe hypoglycemia occurred during the study period. Symptomatic hypoglycemia was more common in the group on exenatide, but this occurred in only 5 patients, and the clinical significance of this is uncertain. Insulin dosage changes on U-500 regular insulin were variable but tended to be lower in those subjects on exenatide. U-500 regular insulin + metformin is effective for the treatment of T2DM patients with severe insulin resistance. The addition of exenatide may ameliorate potential weight gain but provides no additional improvement in glycemia.

Effect of re-coaching on self-injection of insulin in older diabetic patients - Impact of cognitive impairment.

PubMed

Omori, Keiko; Kawamura, Takahiko; Urata, Misako; Matsuura, Mayumi; Kusama, Minoru; Imamine, Rui; Watarai, Atsuko; Nakashima, Eitaro; Umemura, Toshitaka; Hotta, Nigishi

2017-08-01

We investigated the effect of re-coaching on self-injection of insulin and impact of cognitive function in 100 older diabetic patients. We examined patients on a variety of skills and knowledge regarding self-injection of insulin and evaluated the effect of re-coaching the patients after 3months and 4years. We also investigated the influence of cognitive impairment (CI) on coaching. Skills scores for self-injection of insulin and HbA1c improved significantly 3months after re-coaching. In 51 patients followed-up for 4years, skills scores were maintained during the 4years, while knowledge scores improved after 3months but then returned to the baseline level. In the group of patients with CI as determined by the Mini-Mental Status Examination, skills scores were similar to those in the group without CI, while knowledge scores were significantly lower as compared with those in the group without CI at any time point. Skills scores were maintained during the 4years regardless of CI. The present study showed that re-coaching in skills for self-injection of insulin was effective in improving and maintaining insulin treatment in older diabetic patients, even if patients had CI. Copyright © 2017 Elsevier B.V. All rights reserved.

Vildagliptin versus insulin in patients with type 2 diabetes mellitus inadequately controlled with sulfonylurea: results from a randomized, 24 week study.

PubMed

Forst, Thomas; Koch, Cornelia; Dworak, Markus

2015-06-01

There is limited evidence to guide the selection of second-line anti-hyperglycemic agents in patients with type 2 diabetes mellitus (T2DM) who are inadequately controlled with sulfonylurea monotherapy and are intolerant to metformin. We compared the efficacy and safety of vildagliptin 50 mg qd and Neutral Protamine Hagedorn (NPH) insulin qd in such patients. This was a 24 week, multicenter, randomized, open-label study. The co-primary endpoints were (i) proportion of patients achieving HbA1c <7.0% without any confirmed hypoglycemic events (HEs) or weight gain ≥3% (composite endpoint); (ii) rate of confirmed HEs. Treatment satisfaction was assessed using the TSQM-9 questionnaire at study end. A total of 162 patients were randomly assigned to vildagliptin (n = 83) and NPH insulin (n = 79). Similar proportion of patients achieved the composite endpoint in vildagliptin versus NPH insulin group (35.4% versus 34.2%; OR 0.985; 95% CI 0.507, 1.915; p = 0.96). After 24 weeks, 48.8% of patients in the vildagliptin group and 60.8% in the NPH insulin group achieved HbA1c <7.0%; 13.4% in the vildagliptin group and 29.1% in the insulin group had at least one confirmed HE; while 11.0% in the vildagliptin group and 22.8% in the insulin group experienced weight gain. The rate of confirmed HEs was significantly lower in patients receiving vildagliptin versus NPH insulin (1.3 versus 5.1 events per year). The TSQM-9 score for 'convenience' at week 24 increased significantly more with vildagliptin than with NPH insulin. Addition of vildagliptin and NPH insulin resulted in a similar number of patients reaching HbA1c target without HEs or weight gain in T2DM patients inadequately controlled with sulfonylurea. The addition of vildagliptin to sulfonylurea could be considered as a treatment option prior to intensification with insulin, with the advantages of a lower HE rate and greater patient convenience. Study results are limited by a higher drop-out rate in the vildagliptin arm.

Prevention of Insulin Resistance by Dietary Intervention among Pregnant Mothers: A Randomized Controlled Trial.

PubMed

Goodarzi-Khoigani, Masoomeh; Mazloomy Mahmoodabad, Seyed Saeed; Baghiani Moghadam, Mohammad Hossein; Nadjarzadeh, Azadeh; Mardanian, Farahnaz; Fallahzadeh, Hossein; Dadkhah-Tirani, Azam

2017-01-01

Chronic insulin resistance (IR) is a basic part of the pathophysiology of gestational diabetes mellitus. Nutrition significantly impacts IR and weight loss reduces insulin levels, whereas weight gain increases the concentrations. Therefore, we surveyed the effect of nutrition intervention on IR in pregnant women and whether this effect is irrespective of weight gaining in accordance with Institute of Medicine limits. This prospective, randomized clinical trial was carried out among 150 primiparous pregnant mothers in fifteen health centers, five hospitals, and 15 private obstetrical offices in Isfahan. The nutrition intervention included education of healthy diet with emphasize on 50%-55% of total energy intake from carbohydrate (especially complex carbohydrates), 25%-30% from fat (to increase mono unsaturated fatty acids and decrease saturated and trans-fatty acids), and 15%-20% from protein during pregnancy for experimental group. The controls received the usual prenatal care by their health-care providers. This trial decreased pregnancy-induced insulin increases ( P = 0.01) and IR marginally ( P = 0.05). ANCOVA demonstrated that control of gestational weight gaining was more effective to decrease IR ( P = 0.02) while insulin values decreased by nutrition intervention and irrespective of weight control ( P = 0.06). Fasting plasma glucose (FPG) concentrations did not decrease by intervention ( P = 0.56) or weight management ( P = 0.15). The current intervention was effective to decrease pregnancy-induced insulin increases and IR. Considering study results on FPG levels and incidence of GDM, we suggest repeat of study design in a larger sample.

Hypoglycemic potency of novel trivalent chromium in hyperglycemic insulin-deficient rats.

PubMed

Machaliński, Bogusław; Walczak, Mieczysław; Syrenicz, Anhelli; Machalińska, Anna; Grymuła, Katarzyna; Stecewicz, Iwona; Wiszniewska, Barbara; Dabkowska, Elzbieta

2006-01-01

Two sources of chromium III, "chromium 454" and "chromium picolinate," were tested in insulin-deficient Streptozocin-treated diabetic rats. This model was selected in order to evaluate the possibility of any hypoglycemic potency of chromium in a relative absence of blood insulin concentration. Three weeks of the treatment with CRC454 and CrP resulted in a 38% and 11% reduction of blood glucose levels, respectively. Body weight gains were equally improved by both treatments. Blood levels of CK, ALT and AST were significantly reduced by CRC454 and CrP. These results might suggest that any hypoglycemic effect of trivalent chromium under insulin-deficient conditions could be largely dependent upon the type of chromium agent and associated characteristics such as solubility and bioavalibility. In contrast, improvement of body weight gains and blood levels of CK, AST and ALT seems to be less dependent on the type of chromium compound under these experimental conditions. In conclusion, CRC454 showed significant reduction of hyperglycemia under insulin-deficient conditions.

Effect of increasing body condition on key regulators of fat metabolism in subcutaneous adipose tissue depot and circulation of nonlactating dairy cows.

PubMed

Locher, L; Häussler, S; Laubenthal, L; Singh, S P; Winkler, J; Kinoshita, A; Kenéz, Á; Rehage, J; Huber, K; Sauerwein, H; Dänicke, S

2015-02-01

In response to negative energy balance, overconditioned cows mobilize more body fat than thin cows and subsequently are prone to develop metabolic disorders. Changes in adipose tissue (AT) metabolism are barely investigated in overconditioned cows. Therefore, the objective was to investigate the effect of increasing body condition on key regulator proteins of fat metabolism in subcutaneous AT and circulation of dairy cows. Nonlactating, nonpregnant dairy cows (n=8) investigated in the current study served as a model to elucidate the changes in the course of overcondition independent from physiological changes related to gestation, parturition, and lactation. Cows were fed diets with increasing portions of concentrate during the first 6wk of the experiment until 60% were reached, which was maintained for 9wk. Biopsy samples from AT of the subcutaneous tailhead region were collected every 8wk, whereas blood was sampled monthly. Within the experimental period cows had an average BW gain of 243±33.3 kg. Leptin and insulin concentrations were increased until wk 12. Based on serum concentrations of glucose, insulin, and nonesterified fatty acids, the surrogate indices for insulin sensitivity were calculated. High-concentrate feeding led to decreased quantitative insulin sensitivity check index and homeostasis model assessment due to high insulin and glucose concentrations indicating decreased insulin sensitivity. Adiponectin, an adipokine-promoting insulin sensitivity, decreased in subcutaneous AT, but remained unchanged in the circulation. The high-concentrate diet affected key enzymes reflecting AT metabolism such as AMP-activated protein kinase and hormone-sensitive lipase, both represented as the proportion of the phosphorylated protein to total protein, as well as fatty acid synthase. The extent of phosphorylation of AMP-activated protein kinase and the protein expression of fatty acid synthase were inversely regulated throughout the experimental period, whereas the extent of phosphorylation of hormone-sensitive lipase was consistently decreasing by the high-concentrate diet. Overcondition in nonpregnant, nonlactating dairy cows changed the expression of key regulator proteins of AT metabolism and circulation accompanied by impaired insulin sensitivity, which might increase the risk for metabolic disorders. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Lowering Plasma Glucose Concentration by Inhibiting Renal Sodium-Glucose Co-Transport

PubMed Central

Abdul-Ghani, Muhammad A; DeFronzo, Ralph A

2017-01-01

Maintaining normoglycaemia not only reduces the risk of diabetic microvascular complications but also corrects the metabolic abnormalities that contribute to the development and progression of hyperglycaemia (i.e. insulin resistance and beta-cell dysfunction). Progressive beta-cell failure, in addition to the multiple side effects associated with many current antihyperglycaemic agents (e.g., hypoglycaemia and weight gain) presents major obstacle to the achievement of the recommended goal of glycaemic control in patients with diabetes mellitus (DM). Thus, novel effective therapies are needed for optimal glucose control in subjects with DM. Recently, specific inhibitors of renal sodium glucose cotransporter 2 (SGLT2) have been developed to produce glucosuria and lower the plasma glucose concentration. Because of their unique mechanism of action (which is independent of the secretion and action of insulin), these agents are effective in lowering the plasma glucose concentration in all stages of DM and can be combined with all other antidiabetic agents. In this review, we summarize the available data concerning the mechanism of action, efficacy and safety of this novel class of antidiabetic agent. PMID:24690096

Fat-cell mass, serum leptin and adiponectin changes during weight gain and loss in yellow-bellied marmots (Marmota flaviventris).

PubMed

Florant, Gregory L; Porst, Heather; Peiffer, Aubrey; Hudachek, Susan F; Pittman, Chris; Summers, Scott A; Rajala, Michael W; Scherer, Philipp E

2004-11-01

Leptin and adiponectin are proteins produced and secreted from white adipose tissue and are important regulators of energy balance and insulin sensitivity. Seasonal changes in leptin and adiponectin have not been investigated in mammalian hibernators in relationship to changes in fat cell and fat mass. We sought to determine the relationship between serum leptin and adiponectin levels with seasonal changes in lipid mass. We collected serum and tissue samples from marmots (Marmota flaviventris) in different seasons while measuring changes in fat mass, including fat-cell size. We found that leptin is positively associated with increasing fat mass and fat-cell size, while adiponectin is negatively associated with increasing lipid mass. These findings are consistent with the putative roles of these adipokines: leptin increases with fat mass and is involved in enhancing lipid oxidation while adiponectin appears to be higher in summer when hepatic insulin sensitivity should be maintained since the animals are eating. Our data suggest that during autumn/winter animals have switched from a lipogenic condition to a lipolytic state, which may include leptin resistance.

Comparison of grass haylage digestibility and metabolic plasma profile in Icelandic and Standardbred horses.

PubMed

Ragnarsson, S; Jansson, A

2011-06-01

The aim of the present study was to compare digestibility and metabolic response in Icelandic and Standardbred horses fed two grass haylages harvested at different stages of maturity. Six horses of each breed were used in a 24-day change-over design. A total collection of faeces was made on days 15-17 and 22-24. Blood samples were collected on day 24 of each period and analysed for total plasma protein (TPP), plasma urea, non-esterified fatty acids, cortisol and insulin concentration. There were no differences in digestibility coefficients of crude protein, neutral detergent fibre or energy between breeds but organic matter digestibility was higher in the Standardbred horses. On both haylages, the Icelandic horses gained weight whereas the Standardbred horses lost weight. The Icelandic horses had higher TPP, plasma insulin and lower plasma urea concentrations. Our results indicate that the Icelandic horse may be more prone to maintain positive energy balance in relation to the Standardbred horse, but there were no indication of a better digestive capacity in the Icelandic horses. © 2010 Blackwell Verlag GmbH.

Evaluation of insulin secretion and action in New World camelids.

PubMed

Firshman, Anna M; Cebra, Christopher K; Schanbacher, Barbara J; Seaquist, Elizabeth R

2013-01-01

To measure and compare insulin secretion and sensitivity in healthy alpacas and llamas via glucose clamping techniques. 8 llamas and 8 alpacas. Hyperinsulinemic euglycemic clamping (HEC) and hyperglycemic clamping (HGC) were performed on each camelid in a crossover design with a minimum 48-hour washout period between clamping procedures. The HEC technique was performed to measure insulin sensitivity. Insulin was infused IV at 6 mU/min/kg for 4 hours, and an IV infusion of glucose was adjusted to maintain blood glucose concentration at 150 mg/dL. Concentrations of blood glucose and plasma insulin were determined throughout. The HGC technique was performed to assess insulin secretion in response to exogenous glucose infusion. An IV infusion of glucose was administered to maintain blood glucose concentration at 320 mg/dL for 3 hours, and concentrations of blood glucose and plasma insulin were determined throughout. Alpacas and llamas were not significantly different with respect to whole-body insulin sensitivity during HEC or in pancreatic β-cell response during HGC. Alpacas and llamas had markedly lower insulin sensitivity during HEC and markedly lower pancreatic β-cell response during HGC, in comparison with many other species. New World camelids had lower glucose-induced insulin secretion and marked insulin resistance in comparison with other species. This likely contributes to the disorders of fat and glucose metabolism that are common to camelids.

Space Grown Insulin Crystals Provide New Data on Diabetes

NASA Technical Reports Server (NTRS)

1998-01-01

Diabetic patients may someday reduce their insulin injections and lead more normal lives because of new insights gained through innovative space research in which insulin crystals were grown on the Space Shuttle. Results from a 1994 insulin crystals growth experiment in space are leading to a new understanding of protein insulin. Lack of insulin is the cause of diabetes, a disease that accounts for one-seventh of the nation's health care costs. Champion Deivanaygam, a researcher at the Center for Macromolecular Crystallography at the University of Alabama in Birmingham, assists in this work. Photo credit: NASA/Marshall Space Flight Center (MSFC)

Dispelling Myths about Nicotine Replacement Therapy

MedlinePlus

... of nicotine gum is associated with hyperinsulinemia and insulin resistance. Circulation. 1996;94:878-881. 16. Epifano L, ... R, Shafer Z, Fainaru M. Weight gain and insulin resistance during nicotine replacement therapy. Clin Cardiol. 1999;22: ...

Cost-Effectiveness of IDegLira Versus Insulin Intensification Regimens for the Treatment of Adults with Type 2 Diabetes in the Czech Republic.

PubMed

Kvapil, Milan; Prázný, Martin; Holik, Pavel; Rychna, Karel; Hunt, Barnaby

2017-12-01

The aim of this study was to evaluate the long-term cost-effectiveness of the insulin degludec/liraglutide combination (IDegLira) versus basal insulin intensification strategies for patients with type 2 diabetes mellitus (T2DM) not optimally controlled on basal insulin in the Czech Republic. Cost-effectiveness was evaluated using the QuintilesIMS Health CORE Diabetes model, an interactive internet-based model that simulates clinical outcomes and costs for cohorts of patients with diabetes. The analysis was conducted from the perspective of the Czech Republic public payer. Sensitivity analyses were conducted to explore the sensitivity of the model to plausible variations in key parameters. The use of IDegLira was associated with an improvement in the quality-adjusted life expectancy of 0.31 quality-adjusted life-years (QALYs), at an additional cost of Czech Koruna (CZK) 107,829 over a patient's lifetime compared with basal-bolus therapy, generating an incremental cost-effectiveness ratio (ICER) of CZK 345,052 per QALY gained. In a scenario analysis, IDegLira was associated with an ICER of CZK 693,763 per QALY gained compared to basal insulin + glucagon-like peptide-1 receptor agonist (GLP-1 RA). The ICERs are below the generally accepted willingness-to-pay threshold (CZK 1,100,000/QALY gained at the time of this analysis). Results from this evaluation suggest that IDegLira is a cost-effective treatment option compared with basal-bolus therapy and basal insulin + GLP-1 RA for patients with T2DM in the Czech Republic whose diabetes is not optimally controlled with basal insulin. Novo Nordisk.

Improvement of Insulin Sensitivity by Isoenergy High Carbohydrate Traditional Asian Diet: A Randomized Controlled Pilot Feasibility Study

PubMed Central

Hsu, William C.; Lau, Ka Hei Karen; Matsumoto, Motonobu; Moghazy, Dalia; Keenan, Hillary; King, George L.

2014-01-01

The prevalence of diabetes is rising dramatically among Asians, with increased consumption of the typical Western diet as one possible cause. We explored the metabolic responses in East Asian Americans (AA) and Caucasian Americans (CA) when transitioning from a traditional Asian diet (TAD) to a typical Western diet (TWD), which has not been reported before. This 16-week randomized control pilot feasibility study, included 28AA and 22CA who were at risk of developing type 2 diabetes. Eight weeks of TAD were provided to all participants, followed by 8 weeks of isoenergy TWD (intervention) or TAD (control). Anthropometric measures, lipid profile, insulin resistance and inflammatory markers were assessed. While on TAD, both AA and CA improved in insulin AUC (−960.2 µU/mL×h, P = 0.001) and reduced in weight (−1.6 kg; P<0.001), body fat (−1.7%, P<0.001) and trunk fat (−2.2%, P<0.001). Comparing changes from TAD to TWD, AA had a smaller weight gain (−1.8 to 0.3 kg, P<0.001) than CA (−1.4 to 0.9 kg, P = 0.001), but a greater increase in insulin AUC (AA: −1402.4 to 606.2 µU/mL×h, P = 0.015 vs CA: −466.0 to 223.5 µU/mL×h, P = 0.034) and homeostatic static model assessment-insulin resistance (HOMA-IR) (AA: −0.3 to 0.2, P = 0.042 vs CA: −0.1 to 0.0, P = 0.221). Despite efforts to maintain isoenergy state and consumption of similar energy, TAD induced weight loss and improved insulin sensitivity in both groups, while TWD worsened the metabolic profile. Trial Registration: ClinicalTrials.gov NCT00379548 PMID:25226279

Diet-induced obesity exacerbates metabolic and behavioral effects of polycystic ovary syndrome in a rodent model.

PubMed

Ressler, Ilana B; Grayson, Bernadette E; Ulrich-Lai, Yvonne M; Seeley, Randy J

2015-06-15

Polycystic ovary syndrome (PCOS) is the most common endocrinopathy affecting women of reproductive age. Although a comorbidity of PCOS is obesity, many are lean. We hypothesized that increased saturated fat consumption and obesity would exacerbate metabolic and stress indices in a rodent model of PCOS. Female rats were implanted with the nonaromatizable androgen dihydrotestosterone (DHT) or placebo pellets prior to puberty. Half of each group was maintained ad libitum on either a high-fat diet (HFD; 40% butter fat calories) or nutrient-matched low-fat diet (LFD). Irrespective of diet, DHT-treated animals gained more body weight, had irregular cycles, and were glucose intolerant compared with controls on both diets. HFD/DHT animals had the highest levels of fat mass and insulin resistance. DHT animals demonstrated increased anxiety-related behavior in the elevated plus maze by decreased distance traveled and time in the open arms. HFD consumption increased immobility during the forced-swim test. DHT treatment suppressed diurnal corticosterone measurements in both diet groups. In parallel, DHT treatment significantly dampened stress responsivity to a mild stressor. Brains of DHT animals showed attenuated c-Fos activation in the ventromedial hypothalamus and arcuate nucleus; irrespective of DHT-treatment, however, all HFD animals had elevated hypothalamic paraventricular nucleus c-Fos activation. Whereas hyperandrogenism drives overall body weight gain, glucose intolerance, anxiety behaviors, and stress responsivity, HFD consumption exacerbates the effect of androgens on adiposity, insulin resistance, and depressive behaviors. Copyright © 2015 the American Physiological Society.

Diet-induced obesity exacerbates metabolic and behavioral effects of polycystic ovary syndrome in a rodent model

PubMed Central

Ressler, Ilana B.; Grayson, Bernadette E.; Ulrich-Lai, Yvonne M.

2015-01-01

Polycystic ovary syndrome (PCOS) is the most common endocrinopathy affecting women of reproductive age. Although a comorbidity of PCOS is obesity, many are lean. We hypothesized that increased saturated fat consumption and obesity would exacerbate metabolic and stress indices in a rodent model of PCOS. Female rats were implanted with the nonaromatizable androgen dihydrotestosterone (DHT) or placebo pellets prior to puberty. Half of each group was maintained ad libitum on either a high-fat diet (HFD; 40% butter fat calories) or nutrient-matched low-fat diet (LFD). Irrespective of diet, DHT-treated animals gained more body weight, had irregular cycles, and were glucose intolerant compared with controls on both diets. HFD/DHT animals had the highest levels of fat mass and insulin resistance. DHT animals demonstrated increased anxiety-related behavior in the elevated plus maze by decreased distance traveled and time in the open arms. HFD consumption increased immobility during the forced-swim test. DHT treatment suppressed diurnal corticosterone measurements in both diet groups. In parallel, DHT treatment significantly dampened stress responsivity to a mild stressor. Brains of DHT animals showed attenuated c-Fos activation in the ventromedial hypothalamus and arcuate nucleus; irrespective of DHT-treatment, however, all HFD animals had elevated hypothalamic paraventricular nucleus c-Fos activation. Whereas hyperandrogenism drives overall body weight gain, glucose intolerance, anxiety behaviors, and stress responsivity, HFD consumption exacerbates the effect of androgens on adiposity, insulin resistance, and depressive behaviors. PMID:26078189

Pressure hyperalgesia in hind limb suspended rats.

PubMed

Chowdhury, Parimal; Soulsby, Michael E; Jayroe, John; Akel, Nisreen S; Gaddy, Dana; Dobretsov, Maxim

2011-10-01

Spaceflight and simulated microgravity often associate with pain and prediabetes. Streptozotocin (STZ)-induced moderate insulinopenia rat models of prediabetes result in pressure hyperalgesia. The current study was designed to determine whether or not simulated microgravity induced by hind limb suspension (HLS) in rats lead to insulinopenia and pressure hyperalgesia. Adult male rats were divided into HLS (N = 20) and control, non-suspended (N = 16) groups, respectively. Bodyweight and hind limb pressure-pain withdrawal threshold (PPT) were measured at regular 2-5 d intervals for 7 d before and 12-13 d after HLS. Bodyweights and PPT of control and HLS animals measured on the day of suspension were not different. During the experiment, control rats gained 61 +/- 5 g, but maintained their PPT at the baseline level. Suspended rats gained 26 +/- 3 g of weight during the same time period and their PPT declined from 105 +/- 6 g to 84 +/- 6 g. Neither blood glucose nor pancreatic islet density and area were affected by HLS. However, the random plasma insulin of HLS rats was significantly lower than that of control animals (1.6 +/- 0.2 vs. 2.7 +/- 0.2 ng ml(-1)). The observed relationship between insulin and PPT levels in the HLS rats was similar to that observed in rats with STZ-induced insulinopenia. These data suggest that moderate insulinopenia may affect the rat's sensitivity to deep pressure directly, without affecting glucose homeostasis. In addition, our data suggest that HLS rats may develop peripheral neuropathy.

Biotechnology

NASA Image and Video Library

1998-06-03

Diabetic patients may someday reduce their insulin injections and lead more normal lives because of new insights gained through innovative space research in which insulin crystals were grown on the Space Shuttle. Results from a 1994 insulin crystals growth experiment in space are leading to a new understanding of protein insulin. Lack of insulin is the cause of diabetes, a disease that accounts for one-seventh of the nation's health care costs. Champion Deivanaygam, a researcher at the Center for Macromolecular Crystallography at the University of Alabama in Birmingham, assists in this work. Photo credit: NASA/Marshall Space Flight Center (MSFC)

Weight gain as a consequence of living a modern lifestyle: a discussion of barriers to effective weight control and how to overcome them

PubMed Central

Seaman, David R.

2013-01-01

Objective The purpose of this commentary is to discuss modern lifestyle factors that promote weight gain and to suggest methods for clinicians to more effectively educate patients about weight management. Discussion Most adults in the United States are overweight or obese. Multiple factors related to the modern lifestyle appear to play causal roles. In general, the population maintains sedentary lives and overconsumes calorie-dense foods. In particular, refined carbohydrates negatively impact metabolism and stimulate neural addiction mechanisms, which facilitate weight gain. As adipose tissue mass accumulates, satiation centers in the hypothalamus become resistant to insulin and leptin, which leads to increased caloric consumption. Several behavior issues further augment weight gain, such as eating too quickly, a lack of sleep, high stress levels, and a lack of exercise. Finally, adipose tissue accumulation alters the body weight set point, which leads to metabolic changes that function to resist weight loss efforts. Each of these factors may work together to augment weight gain and promote obesity. Health care providers, such as chiropractic physicians, who educate patients on wellness, prevention, and lifestyle changes are well positioned to address these issues. Conclusion People need to be educated about the modern lifestyle factors that prevent effective weight management. Without this knowledge and the associated practical application of lifestyle choices that prevent weight gain, becoming overweight or obese appears to be an unavoidable consequence of living a modern lifestyle. PMID:25067929

Incretin-based therapy in combination with basal insulin: a promising tactic for the treatment of type 2 diabetes.

PubMed

Vora, J; Bain, S C; Damci, T; Dzida, G; Hollander, P; Meneghini, L F; Ross, S A

2013-02-01

Incretin therapies such as dipeptidyl peptidase-4 inhibitors (DPP-4Is) and GLP-1 receptor agonists (GLP-1RAs) have become well-established treatments for type 2 diabetes. Both drug classes reduce blood glucose through physiological pathways mediated by the GLP-1 receptor, resulting in glucose-dependent enhancement of residual insulin secretion and inhibition of glucagon secretion. In addition, the GLP-1RAs reduce gastrointestinal motility and appear to have appetite-suppressing actions and, so, are often able to produce clinically useful weight loss. The glucose-dependency of their glucagon-inhibiting and insulin-enhancing effects, together with their weight-sparing properties, make the incretin therapies a logical proposition for use in combination with exogenous basal insulin therapy. This combination offers the prospect of an additive or synergistic glucose-lowering effect without a greatly elevated risk of hypoglycaemia compared with insulin monotherapy, and any insulin-associated weight gain might also be mitigated. Furthermore, the incretin therapies can be combined with metformin, which is usually continued when basal insulin is introduced in type 2 diabetes. Although the combination of incretin and insulin therapy is currently not addressed in internationally recognized treatment guidelines, several clinical studies have assessed its use. The data, summarized in this review, are encouraging and show that glycaemic control is improved and weight gain is limited or reversed (especially with the combined use of GLP-1RAs and basal insulin), and that the use of an incretin therapy can also greatly reduce insulin dose requirements. The addition of basal insulin to established incretin therapy is straightforward, but insulin dose adjustment (though not discontinuation) is usually necessary if the sequence is reversed. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Tracking weight change, insulin resistance, stress, and aerobic fitness over 4 years of college.

PubMed

Hopper, Mari K; Moninger, Shana Lynn

2017-01-01

To determine if weight gain is accompanied by development of insulin resistance (IR) during 4 years in college. Two cohorts of college students were enrolled in fall semesters 2009 and 2010 and tracked for 4 years. Following a 12-hour fast, subjects reported for measurement of body mass index (BMI), perceived stress (PSS), aerobic fitness, and blood glucose, insulin, and lipids. In the first year, 33% of subjects were overweight or obese, and 20% were hyperinsulinemic. Year 4 had 29 remaining subjects with disproportionate attrition of overweight and obese individuals. Just over half the subjects gained weight (WI), whereas nearly 30% lost considerable amounts (WD). WD showed significant decline in fasting insulin, low-density lipoprotein (LDL) cholesterol, and PSS from year 1. WI was primarily highly fit men who did not demonstrate increased IR. WI was not associated with IR over 4 years of college.

Determinants of weight gain in the action to control cardiovascular risk in diabetes trial.

PubMed

Fonseca, Vivian; McDuffie, Roberta; Calles, Jorge; Cohen, Robert M; Feeney, Patricia; Feinglos, Mark; Gerstein, Hertzel C; Ismail-Beigi, Faramarz; Morgan, Timothy M; Pop-Busui, Rodica; Riddle, Matthew C

2013-08-01

Identify determinants of weight gain in people with type 2 diabetes mellitus (T2DM) allocated to intensive versus standard glycemic control in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial. We studied determinants of weight gain over 2 years in 8,929 participants (4,425 intensive arm and 4,504 standard arm) with T2DM in the ACCORD trial. We used general linear models to examine the association between each baseline characteristic and weight change at the 2-year visit. We fit a linear regression of change in weight and A1C and used general linear models to examine the association between each medication at baseline and weight change at the 2-year visit, stratified by glycemia allocation. There was significantly more weight gain in the intensive glycemia arm of the trial compared with the standard arm (3.0 ± 7.0 vs. 0.3 ± 6.3 kg). On multivariate analysis, younger age, male sex, Asian race, no smoking history, high A1C, baseline BMI of 25-35, high waist circumference, baseline insulin use, and baseline metformin use were independently associated with weight gain over 2 years. Reduction of A1C from baseline was consistently associated with weight gain only when baseline A1C was elevated. Medication usage accounted for <15% of the variability of weight change, with initiation of thiazolidinedione (TZD) use the most prominent factor. Intensive participants who never took insulin or a TZD had an average weight loss of 2.9 kg during the first 2 years of the trial. In contrast, intensive participants who had never previously used insulin or TZD but began this combination after enrolling in the ACCORD trial had a weight gain of 4.6-5.3 kg at 2 years. Weight gain in ACCORD was greater with intensive than with standard treatment and generally associated with reduction of A1C from elevated baseline values. Initiation of TZD and/or insulin therapy was the most important medication-related factor associated with weight gain.

Gestational weight gain and body mass indexes have an impact on the outcomes of diabetic mothers and infants.

PubMed

Maayan-Metzger, Ayala; Schushan-Eisen, Irit; Strauss, Tzipora; Globus, Omer; Leibovitch, Leah

2015-11-01

This study evaluated mothers with diabetes to determine whether prepregnancy body mass index (BMI), BMI on delivery or gestational weight gain (GWG) had the greatest impact on maternal and neonatal outcomes. We retrospectively examined the medical charts of 634 full-term infants born to mothers with gestational diabetes mellitus not requiring insulin (n = 476), gestational diabetes mellitus requiring insulin (n = 140) and insulin-dependent diabetes mellitus (n = 18). Data regarding maternal BMI before pregnancy and on delivery were recorded, as well as maternal and neonatal complications. Infants born to women who gained more than the recommended weight during pregnancy had higher birthweights, higher rates of meconium-stained amniotic fluid and neonatal hypoglycaemia. Using logistic regression, Caesarean section delivery was predicted by gestational diabetes requiring insulin, with an odds ratio (OR) of 1.76, maternal hypertension (OR 2.4), infants born large for gestational age (OR 2.78) and maternal BMI ≥ 30 on delivery (OR 1.06). Neonatal complications were predicted by maternal insulin-dependent diabetes (OR 5.21), lower gestational age (OR 0.8) and GWG above the recommended amount (OR 1.56). Women with diabetes should be made aware that higher GWG can lead to Caesarean section delivery, infant macrosomia and other neonatal complications. ©2015 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

TIF-IA-dependent regulation of ribosome synthesis in drosophila muscle is required to maintain systemic insulin signaling and larval growth.

PubMed

Ghosh, Abhishek; Rideout, Elizabeth J; Grewal, Savraj S

2014-10-01

The conserved TOR kinase signaling network links nutrient availability to cell, tissue and body growth in animals. One important growth-regulatory target of TOR signaling is ribosome biogenesis. Studies in yeast and mammalian cell culture have described how TOR controls rRNA synthesis-a limiting step in ribosome biogenesis-via the RNA Polymerase I transcription factor TIF-IA. However, the contribution of TOR-dependent ribosome synthesis to tissue and body growth in animals is less clear. Here we show in Drosophila larvae that ribosome synthesis in muscle is required non-autonomously to maintain normal body growth and development. We find that amino acid starvation and TOR inhibition lead to reduced levels of TIF-IA, and decreased rRNA synthesis in larval muscle. When we mimic this decrease in muscle ribosome synthesis using RNAi-mediated knockdown of TIF-IA, we observe delayed larval development and reduced body growth. This reduction in growth is caused by lowered systemic insulin signaling via two endocrine responses: reduced expression of Drosophila insulin-like peptides (dILPs) from the brain and increased expression of Imp-L2-a secreted factor that binds and inhibits dILP activity-from muscle. We also observed that maintaining TIF-IA levels in muscle could partially reverse the starvation-mediated suppression of systemic insulin signaling. Finally, we show that activation of TOR specifically in muscle can increase overall body size and this effect requires TIF-IA function. These data suggest that muscle ribosome synthesis functions as a nutrient-dependent checkpoint for overall body growth: in nutrient rich conditions, TOR is required to maintain levels of TIF-IA and ribosome synthesis to promote high levels of systemic insulin, but under conditions of starvation stress, reduced muscle ribosome synthesis triggers an endocrine response that limits systemic insulin signaling to restrict growth and maintain homeostasis.

TIF-IA-Dependent Regulation of Ribosome Synthesis in Drosophila Muscle Is Required to Maintain Systemic Insulin Signaling and Larval Growth

PubMed Central

Ghosh, Abhishek; Rideout, Elizabeth J.; Grewal, Savraj S.

2014-01-01

The conserved TOR kinase signaling network links nutrient availability to cell, tissue and body growth in animals. One important growth-regulatory target of TOR signaling is ribosome biogenesis. Studies in yeast and mammalian cell culture have described how TOR controls rRNA synthesis—a limiting step in ribosome biogenesis—via the RNA Polymerase I transcription factor TIF-IA. However, the contribution of TOR-dependent ribosome synthesis to tissue and body growth in animals is less clear. Here we show in Drosophila larvae that ribosome synthesis in muscle is required non-autonomously to maintain normal body growth and development. We find that amino acid starvation and TOR inhibition lead to reduced levels of TIF-IA, and decreased rRNA synthesis in larval muscle. When we mimic this decrease in muscle ribosome synthesis using RNAi-mediated knockdown of TIF-IA, we observe delayed larval development and reduced body growth. This reduction in growth is caused by lowered systemic insulin signaling via two endocrine responses: reduced expression of Drosophila insulin-like peptides (dILPs) from the brain and increased expression of Imp-L2—a secreted factor that binds and inhibits dILP activity—from muscle. We also observed that maintaining TIF-IA levels in muscle could partially reverse the starvation-mediated suppression of systemic insulin signaling. Finally, we show that activation of TOR specifically in muscle can increase overall body size and this effect requires TIF-IA function. These data suggest that muscle ribosome synthesis functions as a nutrient-dependent checkpoint for overall body growth: in nutrient rich conditions, TOR is required to maintain levels of TIF-IA and ribosome synthesis to promote high levels of systemic insulin, but under conditions of starvation stress, reduced muscle ribosome synthesis triggers an endocrine response that limits systemic insulin signaling to restrict growth and maintain homeostasis. PMID:25356674

Insulin resistance and the metabolism of branched-chain amino acids in humans.

PubMed

Adeva, María M; Calviño, Jesús; Souto, Gema; Donapetry, Cristóbal

2012-07-01

Peripheral resistance to insulin action is the major mechanism causing the metabolic syndrome and eventually type 2 diabetes mellitus. The metabolic derangement associated with insulin resistance is extensive and not restricted to carbohydrates. The branched-chain amino acids (BCAAs) are particularly responsive to the inhibitory insulin action on amino acid release by skeletal muscle and their metabolism is profoundly altered in conditions featuring insulin resistance, insulin deficiency, or both. Obesity, the metabolic syndrome and diabetes mellitus display a gradual increase in the plasma concentration of BCAAs, from the obesity-related low-grade insulin-resistant state to the severe deficiency of insulin action in diabetes ketoacidosis. Obesity-associated hyperinsulinemia succeeds in maintaining near-normal or slightly elevated plasma concentration of BCAAs, despite the insulin-resistant state. The low circulating levels of insulin and/or the deeper insulin resistance occurring in diabetes mellitus are associated with more marked elevation in the plasma concentration of BCAAs. In diabetes ketoacidosis, the increase in plasma BCAAs is striking, returning to normal when adequate metabolic control is achieved. The metabolism of BCAAs is also disturbed in other situations typically featuring insulin resistance, including kidney and liver dysfunction. However, notwithstanding the insulin-resistant state, the plasma level of BCAAs in these conditions is lower than in healthy subjects, suggesting that these organs are involved in maintaining BCAAs blood concentration. The pathogenesis of the decreased BCAAs plasma level in kidney and liver dysfunction is unclear, but a decreased afflux of these amino acids into the blood stream has been observed.

A Controlled Study of the Effectiveness of an Adaptive Closed-Loop Algorithm to Minimize Corticosteroid-Induced Stress Hyperglycemia in Type 1 Diabetes

PubMed Central

Youssef, Joseph El; Castle, Jessica R; Branigan, Deborah L; Massoud, Ryan G; Breen, Matthew E; Jacobs, Peter G; Bequette, B Wayne; Ward, W Kenneth

2011-01-01

To be effective in type 1 diabetes, algorithms must be able to limit hyperglycemic excursions resulting from medical and emotional stress. We tested an algorithm that estimates insulin sensitivity at regular intervals and continually adjusts gain factors of a fading memory proportional-derivative (FMPD) algorithm. In order to assess whether the algorithm could appropriately adapt and limit the degree of hyperglycemia, we administered oral hydrocortisone repeatedly to create insulin resistance. We compared this indirect adaptive proportional-derivative (APD) algorithm to the FMPD algorithm, which used fixed gain parameters. Each subject with type 1 diabetes (n = 14) was studied on two occasions, each for 33 h. The APD algorithm consistently identified a fall in insulin sensitivity after hydrocortisone. The gain factors and insulin infusion rates were appropriately increased, leading to satisfactory glycemic control after adaptation (premeal glucose on day 2, 148 ± 6 mg/dl). After sufficient time was allowed for adaptation, the late postprandial glucose increment was significantly lower than when measured shortly after the onset of the steroid effect. In addition, during the controlled comparison, glycemia was significantly lower with the APD algorithm than with the FMPD algorithm. No increase in hypoglycemic frequency was found in the APD-only arm. An afferent system of duplicate amperometric sensors demonstrated a high degree of accuracy; the mean absolute relative difference of the sensor used to control the algorithm was 9.6 ± 0.5%. We conclude that an adaptive algorithm that frequently estimates insulin sensitivity and adjusts gain factors is capable of minimizing corticosteroid-induced stress hyperglycemia. PMID:22226248

Basal Insulin Regimens for Adults with Type 1 Diabetes Mellitus: A Cost-Utility Analysis.

PubMed

Dawoud, Dalia; Fenu, Elisabetta; Higgins, Bernard; Wonderling, David; Amiel, Stephanie A

2017-12-01

To assess the cost-effectiveness of basal insulin regimens for adults with type 1 diabetes mellitus in England. A cost-utility analysis was conducted in accordance with the National Institute for Health and Care Excellence reference case. The UK National Health Service and personal and social services perspective was used and a 3.5% discount rate was applied for both costs and outcomes. Relative effectiveness estimates were based on a systematic review of published trials and a Bayesian network meta-analysis. The IMS CORE Diabetes Model was used, in which net monetary benefit (NMB) was calculated using a threshold of £20,000 per quality-adjusted life-year (QALY) gained. A wide range of sensitivity analyses were conducted. Insulin detemir (twice daily) [iDet (bid)] had the highest mean QALY gain (11.09 QALYs) and NMB (£181,456) per patient over the model time horizon. Compared with the lowest cost strategy (insulin neutral protamine Hagedorn once daily), it had an incremental cost-effectiveness ratio of £7844/QALY gained. Insulin glargine (od) [iGlarg (od)] and iDet (od) were ranked as second and third, with NMBs of £180,893 and £180,423, respectively. iDet (bid) remained the most cost-effective treatment in all the sensitivity analyses performed except when high doses were assumed (>30% increment compared with other regimens), where iGlarg (od) ranked first. iDet (bid) is the most cost-effective regimen, providing the highest QALY gain and NMB. iGlarg (od) and iDet (od) are possible options for those for whom the iDet (bid) regimen is not acceptable or does not achieve required glycemic control. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Space Grown Insulin Crystals Provide New Data on Diabetes

NASA Technical Reports Server (NTRS)

1998-01-01

Diabetic patients may someday reduce their insulin injections and lead more normal lives because of new insights gained through irnovative space research in which insulin crystals were grown on the Space Shuttle. Results from a 1994 insulin crystal growth experiment in space are leading to a new understanding of protein insulin. Lack of insulin is the cause of diabetes, a desease that accounts for one-seventh of the nation's health care costs. Dr. Marianna Long, associate director of the Center of Macromolecular Crystallography at the University of Alabama at Birmingham, is a co-investigator on the research. Photo credit: NASA/Marshall Space Flight Center (MSFC)

Anesthesia with propofol induces insulin resistance systemically in skeletal and cardiac muscles and liver of rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yasuda, Yoshikazu; Fukushima, Yuji; Kaneki, Masao

Highlights: ► Propofol, as a model anesthetic drug, induced whole body insulin resistance. ► Propofol anesthesia decreased glucose infusion rate to maintain euglycemia. ► Propofol decreased insulin-mediated glucose uptake in skeletal and cardiac muscles. ► Propofol increased hepatic glucose output confirming hepatic insulin resistance. -- Abstract: Hyperglycemia together with hepatic and muscle insulin resistance are common features in critically ill patients, and these changes are associated with enhanced inflammatory response, increased susceptibility to infection, muscle wasting, and worsened prognosis. Tight blood glucose control by intensive insulin treatment may reduce the morbidity and mortality in intensive care units. Although some anestheticsmore » have been shown to cause insulin resistance, it remains unknown how and in which tissues insulin resistance is induced by anesthetics. Moreover, the effects of propofol, a clinically relevant intravenous anesthetic, also used in the intensive care unit for sedation, on insulin sensitivity have not yet been investigated. Euglycemic hyperinsulinemic clamp study was performed in rats anesthetized with propofol and conscious unrestrained rats. To evaluate glucose uptake in tissues and hepatic glucose output [{sup 3}H]glucose and 2-deoxy[{sup 14}C]glucose were infused during the clamp study. Anesthesia with propofol induced a marked whole-body insulin resistance compared with conscious rats, as reflected by significantly decreased glucose infusion rate to maintain euglycemia. Insulin-stimulated tissue glucose uptake was decreased in skeletal muscle and heart, and hepatic glucose output was increased in propofol anesthetized rats. Anesthesia with propofol induces systemic insulin resistance along with decreases in insulin-stimulated glucose uptake in skeletal and heart muscle and attenuation of the insulin-mediated suppression of hepatic glucose output in rats.« less

Hormonal control of growth in the wing imaginal disks of Junonia coenia: the relative contributions of insulin and ecdysone.

PubMed

Nijhout, H Frederik; Laub, Emily; Grunert, Laura W

2018-03-19

The wing imaginal disks of Lepidoptera can be grown in tissue culture, but require both insulin and ecdysone to grow normally. Here, we investigate the contributions the two hormones make to growth. Ecdysone is required to maintain mitoses, whereas in the presence of insulin alone mitoses stop. Both ecdysone and insulin stimulate protein synthesis, but only ecdysone stimulates DNA synthesis. Insulin stimulates primarily cytoplasmic growth and an increase in cell size, whereas ecdysone, by virtue of its stimulation of DNA synthesis and mitosis, stimulates growth by an increase in cell number. Although both hormones stimulate protein synthesis, they do so in different spatial patterns. Both hormones stimulate protein synthesis in the inter-vein regions, but ecdysone stimulates synthesis more strongly in the veins and in the margin of the wing disk. We propose that the balance of insulin and ecdysone signaling must be regulated to maintain normal growth, and when growth appears to be due primarily to an increase in cell number, or an increase in cell size, this may indicate growth occurred under conditions that favored a stronger role for ecdysone, or insulin, respectively. © 2018. Published by The Company of Biologists Ltd.

Aqueous extract of Chrysobalanus icaco leaves, in lower doses, prevent fat gain in obese high-fat fed mice.

PubMed

White, P A S; Cercato, L M; Batista, V S; Camargo, E A; De Lucca, W; Oliveira, A S; Silva, F T; Goes, T C; Oliveira, E R A; Moraes, V R S; Nogueira, P C L; De Oliveira E Silva, A M; Quintans-Junior, L J; Lima, B S; Araújo, A A S; Santos, M R V

2016-02-17

Due to the rise in obesity, the necessity for resources and treatments that could reduce the morbidity and mortality associated to this pandemia has emerged. The development of new anti-obesity drugs through herbal sources has been increasing in the past decades which are being used not only as medicine but also as food supplements. Previous studies with the aqueous extract of Chrysobalanus icaco L (AECI) have demonstrated activity on lowering blood glucose levels and body weight. Investigate C. icaco effects in overall adiposity and glycemic homeostasis. C57BL/6J mice were randomly assigned to standard chow (SC) or high-fat diet (HFD) and treated with AECI in 0.35mg/mL or 0.7mg/mL concentrations ad libitum. Food intake, feed efficiency, metabolic efficiency, body, fat pads and gastrocnemius weight, adiposity index, serum lipids, fecal lipid excretion, locomotor activity in the open field test and insulin and glucose tolerance tests were analyzed and compared. The major components of the extract were demonstrated through HPLC and its antioxidant activity analyzed through DPPH and lipid peroxidation. The AECI in the 0.35mg/mL concentration did not affect food intake or body weight. However, it promoted lower adipose tissue gain, TG levels, and fecal lipid excretion, increased locomotor activity and lean mass weight, and normalized insulin sensitivity and glucose tolerance. Moreover, AECI showed the presence of myricetin 3-O-glucuronide, rutin, quercitrin and myricitrin and demonstrated high-antioxidant activity. AECI in lower concentrations can prevent fat storage or enhance fat utilization through the increase of locomotor activity. Also, this reinforces its ability to maintain glucose homeostasis through the normalization of insulin sensitivity and glucose tolerance despite the high-fat diet intake. These activities could be associated to the extract's polyphenol content. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Rapid insulin sensitivity test (RIST).

PubMed

Lautt, W W; Wang, X; Sadri, P; Legare, D J; Macedo, M P

1998-12-01

A rapid insulin sensitivity test (RIST) was recently introduced to assess insulin action in vivo (H. Xie, L. Zhu, Y.L. Zhang, D.J. Legare, and W.W. Lautt. J. Pharmacol. Toxicol. Methods, 35: 77-82. 1996). This technical report describes the current recommended standard operating procedure for the use of the RIST in rats based upon additional experience with approximately 100 tests. We describe the manufacture and use of an arterial-venous shunt that allows rapid multiple arterial samples and intravenous administration of drugs. The RIST procedure involves determination of a stable arterial glucose baseline to define the ideal euglycemic level to be maintained following a 5-min infusion of insulin, with the RIST index being the amount of glucose required to be infused to maintain euglycemia over the test period. Insulin administration by a 5-min infusion is preferable to a 30-s bolus administration. No significant difference was determined between the use of Toronto pork-beef or human insulin. Four consecutive RISTs were carried out in the same animal over 4-5 h with no tendency for change with time. The RIST index is sufficiently sensitive and reproducible to permit establishment of insulin dose-response curves and interference of insulin action by elimination of hepatic parasympathetic nerves, using atropine. This technical report provides the current recommended standard operating procedure for the RIST.

Microgravity

NASA Image and Video Library

1998-06-03

Diabetic patients may someday reduce their insulin injections and lead more normal lives because of new insights gained through irnovative space research in which insulin crystals were grown on the Space Shuttle. Results from a 1994 insulin crystal growth experiment in space are leading to a new understanding of protein insulin. Lack of insulin is the cause of diabetes, a desease that accounts for one-seventh of the nation's health care costs. Dr. Marianna Long, associate director of the Center of Macromolecular Crystallography at the University of Alabama at Birmingham, is a co-investigator on the research. Photo credit: NASA/Marshall Space Flight Center (MSFC)

Metabolic effects of smoking cessation.

PubMed

Harris, Kindred K; Zopey, Mohan; Friedman, Theodore C

2016-05-01

Smoking continues to be the leading cause of preventable death in the USA, despite the vast and widely publicized knowledge about the negative health effects of tobacco smoking. Data show that smoking cessation is often accompanied by weight gain and an improvement in insulin sensitivity over time. However, paradoxically, post-cessation-related obesity might contribute to insulin resistance. Furthermore, post-cessation weight gain is reportedly the number one reason why smokers, especially women, fail to initiate smoking cessation or relapse after initiating smoking cessation. In this Review, we discuss the metabolic effects of stopping smoking and highlight future considerations for smoking cessation programs and therapies to be designed with an emphasis on reducing post-cessation weight gain.

Metabolic effects of smoking cessation

PubMed Central

Harris, Kindred K.; Zopey, Mohan; Friedman, Theodore C.

2016-01-01

Smoking continues to be the leading cause of preventable death in the USA, despite the vast and widely publicized knowledge about the negative health effects of tobacco smoking. Data show that smoking cessation is often accompanied by weight gain and an improvement in insulin sensitivity over time. However, paradoxically, post-cessation-related obesity might contribute to insulin resistance. Furthermore, post-cessation weight gain is reportedly the number one reason why smokers, especially women, fail to initiate smoking cessation or relapse after initiating smoking cessation. In this Review, we discuss the metabolic effects of stopping smoking and highlight future considerations for smoking cessation programs and therapies to be designed with an emphasis on reducing post-cessation weight gain. PMID:26939981

Postnatal weight gain induced by overfeeding pups and maternal high-fat diet during the lactation period modulates glucose metabolism and the production of pancreatic and gastrointestinal peptides.

PubMed

Du, Qinwen; Hosoda, Hiroshi; Umekawa, Takashi; Kinouchi, Toshi; Ito, Natsuki; Miyazato, Mikiya; Kangawa, Kenji; Ikeda, Tomoaki

2015-08-01

The impact of rapid weight gain on glucose metabolism during the early postnatal period remains unclear. We investigated the influence of rapid weight gain under different nutritional conditions on glucose metabolism, focusing on the production of pancreatic and gastric peptides. On postnatal day (PND) 2, C57BL/6N pups were divided into three groups: control (C) pups whose dams were fed a control diet (10%kcal fat) and nursed 10 pups each; maternal high-fat diet (HFD) pups whose dams were fed an HFD (45%kcal fat) and nursed 10 pups each; and overfeeding (OF) pups whose dams were fed the control diet and nursed 4 pups each. Data were collected on PND 7, 14 and 21. The body weight gains of the HFD and OF pups were 1.2 times higher than that of the C pups. On PND 14, the HFD pups had higher blood glucose levels, but there were no significant differences in serum insulin levels between the HFD and C pups. The OF pups had higher blood glucose and serum insulin levels than that of the C pups. Insulin resistance was found in the HFD and OF pups. On PND 14, the content of incretins in the jejunum was increased in the OF pups, and acyl ghrelin in the stomach was upregulated in the HFD and OF pups. These results suggest that neonatal weight gain induced by overfeeding pups and maternal high-fat diet during the early postnatal period modulates the insulin sensitivity and the production of pancreatic and gastrointestinal peptides. Copyright © 2015 Elsevier Inc. All rights reserved.

Insulin Oedema in Newly Diagnosed Type 1 Diabetes Mellitus

PubMed Central

Çetinkaya, Semra; Yılmaz Ağladıoğlu, Sebahat; Peltek Kendirici, Havva Nur; Bilgili, Hatice; Yıldırım, Nurdan; Aycan, Zehra

2010-01-01

Despite the essential role of insulin in the management of patients with insulin deficiency, insulin use can lead to adverse effects such as hypoglycaemia and weight gain. Rarely, crucial fluid retention can occur with insulin therapy, resulting in an oedematous condition. Peripheral or generalised oedema is an extremely rare complication of insulin therapy in the absence of heart, liver or renal involvement. It has been reported in newly diagnosed type 1 diabetes, in poorly controlled type 2 diabetes following the initiation of insulin therapy, and in underweight patients on large doses of insulin. The oedema occurs shortly after the initiation of intensive insulin therapy. We describe two adolescent girls with newly diagnosed type 1 diabetes, who presented with oedema of the lower extremities approximately one week after the initiation of insulin treatment; other causes of oedema were excluded. Spontaneous recovery was observed in both patients. Conflict of interest:None declared. PMID:21274337

Once-daily basal insulin glargine versus thrice-daily prandial insulin lispro in people with type 2 diabetes on oral hypoglycaemic agents (APOLLO): an open randomised controlled trial.

PubMed

Bretzel, Reinhard G; Nuber, Ulrike; Landgraf, Wolfgang; Owens, David R; Bradley, Clare; Linn, Thomas

2008-03-29

As type 2 diabetes mellitus progresses, oral hypoglycaemic agents often fail to maintain blood glucose control and insulin is needed. We investigated whether the addition of once-daily insulin glargine is non-inferior to three-times daily prandial insulin lispro in overall glycaemic control in adults with inadequately controlled type 2 diabetes mellitus taking oral hypoglycaemic agents. In the 44-week, parallel, open study that was undertaken in 69 study sites across Europe and Australia, 418 patients with type 2 diabetes mellitus that was inadequately controlled by oral hypoglycaemic agents were randomly assigned to either insulin glargine taken once daily at the same time every day or to insulin lispro administered three times per day. The primary objective was to compare the change in haemoglobin A(1c) from baseline to endpoint (week 44) between the two regimens. Randomisation was done with a central randomisation service. Analysis was per protocol. This study is registered with ClinicalTrials.gov, number NCT00311818. 205 patients were randomly assigned to insulin glargine and 210 to insulin lispro. Mean haemoglobin A(1c) decrease in the insulin glargine group was -1.7% (from 8.7% [SD 1.0] to 7.0% [0.7]) and -1.9% in the insulin lispro group (from 8.7% [1.0] to 6.8% [0.9]), which was within the predefined limit of 0.4% for non-inferiority (difference=0.157; 95% Cl -0.008 to 0.322). 106 (57%) patients reached haemoglobin A(1c) of 7% or less in the glargine group and 131 (69%) in the lispro group. In the glargine group, the fall in mean fasting blood glucose (-4.3 [SD 2.3] mmol/L vs -1.8 [2.3] mmol/L; p<0.0001) and nocturnal blood glucose (-3.3 [2.8] mmol/L vs -2.6 [2.9] mmol/L; p=0.0041) was better than it was in the insulin lispro group, whereas insulin lispro better controlled postprandial blood glucose throughout the day (p<0.0001). The incidence of hypoglycaemic events was less with insulin glargine than with lispro (5.2 [95% CI 1.9-8.9] vs 24.0 [21-28] events per patient per year; p<0.0001). Respective mean weight gains were 3.01 (SD 4.33) kg and 3.54 (4.48) kg. The improvement of treatment satisfaction was greater for insulin glargine than for insulin lispro (mean difference 3.13; 95% CI 2.04-4.22). A therapeutic regimen involving the addition of either basal or prandial insulin analogue is equally effective in lowering haemoglobin A(1c). We conclude that insulin glargine provides a simple and effective option that is more satisfactory to patients than is lispro for early initiation of insulin therapy, since it was associated with a lower risk of hypoglycaemia, fewer injections, less blood glucose self monitoring, and greater patient satisfaction than was insulin lispro. Sanofi-Aventis.

Treating Type 1 Diabetes Mellitus with a Rapid-Acting Analog Insulin Regimen vs. Regular Human Insulin in Germany: A Long-Term Cost-Effectiveness Evaluation.

PubMed

Valentine, William J; Van Brunt, Kate; Boye, Kristina S; Pollock, Richard F

2018-06-01

The aim of the present study was to evaluate the cost effectiveness of rapid-acting analog insulin relative to regular human insulin in adults with type 1 diabetes mellitus in Germany. The PRIME Diabetes Model, a patient-level, discrete event simulation model, was used to project long-term clinical and cost outcomes for patients with type 1 diabetes from the perspective of a German healthcare payer. Simulated patients had a mean age of 21.5 years, duration of diabetes of 8.6 years, and baseline glycosylated hemoglobin of 7.39%. Regular human insulin and rapid-acting analog insulin regimens reduced glycosylated hemoglobin by 0.312 and 0.402%, respectively. Compared with human insulin, hypoglycemia rate ratios with rapid-acting analog insulin were 0.51 (non-severe nocturnal) and 0.80 (severe). No differences in non-severe diurnal hypoglycemia were modeled. Discount rates of 3% were applied to future costs and clinical benefits accrued over the 50-year time horizon. In the base-case analysis, rapid-acting analog insulin was associated with an improvement in quality-adjusted life expectancy of 1.01 quality-adjusted life-years per patient (12.54 vs. 11.53 quality-adjusted life-years). Rapid-acting analog insulin was also associated with an increase in direct costs of €4490, resulting in an incremental cost-effectiveness ratio of €4427 per quality-adjusted life-year gained vs. human insulin. Sensitivity analyses showed that the base case was driven predominantly by differences in hypoglycemia; abolishing these differences reduced incremental quality-adjusted life expectancy to 0.07 quality-adjusted life-years, yielding an incremental cost-effectiveness ratio of €74,622 per quality-adjusted life-year gained. Rapid-acting analog insulin is associated with beneficial outcomes in patients with type 1 diabetes and is likely to be considered cost effective in the German setting vs. regular human insulin.

Autophagy and its link to type II diabetes mellitus

PubMed Central

Yang, Jai-Sing; Lu, Chi-Cheng; Kuo, Sheng-Chu; Hsu, Yuan-Man; Tsai, Shih-Chang; Chen, Shih-Yin; Chen, Yng-Tay; Lin, Ying-Ju; Huang, Yu-Chuen; Chen, Chao-Jung; Lin, Wei-De; Liao, Wen-Lin; Lin, Wei-Yong; Liu, Yu-Huei; Sheu, Jinn-Chyuan; Tsai, Fuu-Jen

2017-01-01

Autophagy, a double-edged sword for cell survival, is the research object on 2016 Nobel Prize in Physiology or Medicine. Autophagy is a molecular mechanism for maintaining cellular physiology and promoting survival. Defects in autophagy lead to the etiology of many diseases, including diabetes mellitus (DM), cancer, neurodegeneration, infection disease and aging. DM is a metabolic and chronic disorder and has a higher prevalence in the world as well as in Taiwan. The character of diabetes mellitus is hyperglycemia resulting from defects in insulin secretion, insulin action, or both. Type 2 diabetes mellitus (T2DM) is characterized by insulin resistance and failure of producing insulin on pancreatic beta cells. In T2DM, autophagy is not only providing nutrients to maintain cellular energy during fasting, but also removes damaged organelles, lipids and miss-folded proteins. In addition, autophagy plays an important role in pancreatic beta cell dysfunction and insulin resistance. In this review, we summarize the roles of autophagy in T2DM. PMID:28612706

Kinetics of insulin aggregation in aqueous solutions upon agitation in the presence of hydrophobic surfaces.

PubMed Central

Sluzky, V; Tamada, J A; Klibanov, A M; Langer, R

1991-01-01

The stability of protein-based pharmaceuticals (e.g., insulin) is important for their production, storage, and delivery. To gain an understanding of insulin's aggregation mechanism in aqueous solutions, the effects of agitation rate, interfacial interactions, and insulin concentration on the overall aggregation rate were examined. Ultraviolet absorption spectroscopy, high-performance liquid chromatography, and quasielastic light scattering analyses were used to monitor the aggregation reaction and identify intermediate species. The reaction proceeded in two stages; insulin stability was enhanced at higher concentration. Mathematical modeling of proposed kinetic schemes was employed to identify possible reaction pathways and to explain greater stability at higher insulin concentration. Images PMID:1946348

Insulin and branched-chain amino acid depletion during mouse preimplantation embryo culture programmes body weight gain and raised blood pressure during early postnatal life.

PubMed

Velazquez, Miguel A; Sheth, Bhavwanti; Smith, Stephanie J; Eckert, Judith J; Osmond, Clive; Fleming, Tom P

2018-02-01

Mouse maternal low protein diet exclusively during preimplantation development (Emb-LPD) is sufficient to programme altered growth and cardiovascular dysfunction in offspring. Here, we use an in vitro model comprising preimplantation culture in medium depleted in insulin and branched-chain amino acids (BCAA), two proposed embryo programming inductive factors from Emb-LPD studies, to examine the consequences for blastocyst organisation and, after embryo transfer (ET), postnatal disease origin. Two-cell embryos were cultured to blastocyst stage in defined KSOM medium supplemented with four combinations of insulin and BCAA concentrations. Control medium contained serum insulin and uterine luminal fluid amino acid concentrations (including BCAA) found in control mothers from the maternal diet model (N-insulin+N-bcaa). Experimental medium (three groups) contained 50% reduction in insulin and/or BCAA (L-insulin+N-bcaa, N-insulin+L-bcaa, and L-insulin+N-bcaa). Lineage-specific cell numbers of resultant blastocysts were not affected by treatment. Following ET, a combined depletion of insulin and BCAA during embryo culture induced a non sex-specific increase in birth weight and weight gain during early postnatal life. Furthermore, male offspring displayed relative hypertension and female offspring reduced heart/body weight, both characteristics of Emb-LPD offspring. Combined depletion of metabolites also resulted in a strong positive correlation between body weight and glucose metabolism that was absent in the control group. Our results support the notion that composition of preimplantation culture medium can programme development and associate with disease origin affecting postnatal growth and cardiovascular phenotypes and implicate two important nutritional mediators in the inductive mechanism. Our data also have implications for human assisted reproductive treatment (ART) practice. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Once-daily prandial lixisenatide versus once-daily rapid-acting insulin in patients with type 2 diabetes mellitus insufficiently controlled with basal insulin: analysis of data from five randomized, controlled trials.

PubMed

Raccah, Denis; Lin, Jay; Wang, Edward; Germé, Maeva; Perfetti, Riccardo; Bonadonna, Riccardo C; de Pablos-Velasco, Pedro; Roussel, Ronan; Rosenstock, Julio

2014-01-01

To compare the efficacy and safety of lixisenatide (LIXI), a once-daily prandial glucagon-like peptide-1 (GLP-1) receptor agonist, as add-on to basal insulin (Basal+LIXI) versus once-daily rapid-acting insulin (Basal+RAI) in patients with type 2 diabetes mellitus (T2DM). Data were extracted from five randomized controlled trials assessing the efficacy and safety of basal insulin+insulin glulisine (n=3) or basal insulin+LIXI (n=2). Patients in the Basal+LIXI cohort were matched to patients in the Basal+RAI cohort using propensity score matching. In the matched population, Basal+LIXI was twice as likely to reach composite outcomes of glycated haemoglobin (HbA1c) <7% and no symptomatic hypoglycaemia compared with the Basal+RAI group (odds ratio [OR]: 1.90; 95% confidence interval [CI]: 1.01, 3.55; P=0.0455), as well as HbA1c <7% and no severe hypoglycaemia (OR: 1.97; 95 CI: 1.06, 3.66; P=0.0311). Furthermore, Basal+LIXI was more than twice as likely to reach HbA1c <7%, no weight gain and no symptomatic hypoglycaemia (OR: 2.58; 95% CI: 1.23, 5.40; P=0.0119). Both basal+LIXI and Basal+RAI improved glycaemic control in patients with T2DM with inadequate glycaemic control on basal insulin. Basal+LIXI offers an effective therapeutic option to advance basal insulin therapy, improving glucose control without weight gain and with less risk of hypoglycaemia than prandial insulin. © 2013.

Dietary monounsaturated fat in early life regulates IGFBP2: implications for fat mass accretion and insulin sensitivity.

PubMed

Sabin, Matthew A; Yau, Steven W; Russo, Vincenzo C; Clarke, Iain J; Dunshea, Frank R; Chau, Jillian; Cox, Maree; Werther, George A

2011-12-01

The aim of this study was to investigate effects of dietary supplementation with fat or sugar on body composition (BC) and insulin sensitivity (IS) in maturing pigs. Fifty newborn pigs randomized to a control diet or 18% saturated fat (SF), 18% monounsaturated fat (MUF), 18% mixed fat (MF), or 50% sucrose (SUC), from 1 to 16 weeks of age. Outcomes included weight gain, BC (dual energy X-ray absorptiometry, DXA), IS (fasting insulin and hyperinsulinaemic-euglycaemic clamps), fasting Non-Esterified Fatty Acid (NEFA) concentrations, and mRNA expression of genes involved in lipogenesis and IS in skeletal muscle (SM), subcutaneous (SAT), and visceral adipose tissue (VAT). In vitro studies examined direct effects of fatty acids on insulin-like growth factor-binding protein 2 (IGFBP2) mRNA in C2C12 myotubes. While SUC-fed pigs gained most weight (due to larger quantities consumed; P < 0.01), those fed fat-enriched diets exhibited more weight gain per unit energy intake (P < 0.001). Total (P = 0.03) and visceral (P = 0.04) adiposity were greatest in MUF-fed pigs. Whole-body IS was decreased in those fed fat (P = 0.04), with fasting insulin increased in MUF-fed pigs (P = 0.03). SM IGFBP2 mRNA was increased in MUF-fed pigs (P = 0.009) and, in all animals, SM IGFBP2 mRNA correlated with total (P = 0.007) and visceral (P = 0.001) fat, fasting insulin (r = 0.321; P = 0.03) and change in NEFA concentrations (r = 0.285; P = 0.047). Furthermore, exposure of in vitro cultured myotubes to MUF, but not SF, reduced IGFBP2 mRNA suggesting a converse direct effect. In conclusion, diets high in fat, but not sugar, promote visceral adiposity and insulin resistance in maturing pigs, with evidence that fatty acids have direct and indirect effects on IGFBP2 mRNA expression in muscle.

Strict glycaemic control in patients hospitalised in a mixed medical and surgical intensive care unit: a randomised clinical trial

PubMed Central

De La Rosa, Gisela Del Carmen; Donado, Jorge Hernando; Restrepo, Alvaro Humberto; Quintero, Alvaro Mauricio; González, Luis Gabriel; Saldarriaga, Nora Elena; Bedoya, Marisol; Toro, Juan Manuel; Velásquez, Jorge Byron; Valencia, Juan Carlos; Arango, Clara Maria; Aleman, Pablo Henrique; Vasquez, Esdras Martin; Chavarriaga, Juan Carlos; Yepes, Andrés; Pulido, William; Cadavid, Carlos Alberto

2008-01-01

Introduction Critically ill patients can develop hyperglycaemia even if they do not have diabetes. Intensive insulin therapy decreases morbidity and mortality rates in patients in a surgical intensive care unit (ICU) and decreases morbidity in patients in a medical ICU. The effect of this therapy on patients in a mixed medical/surgical ICU is unknown. Our goal was to assess whether the effect of intensive insulin therapy, compared with standard therapy, decreases morbidity and mortality in patients hospitalised in a mixed ICU. Methods This is a prospective, randomised, non-blinded, single-centre clinical trial in a medical/surgical ICU. Patients were randomly assigned to receive either intensive insulin therapy to maintain glucose levels between 80 and 110 mg/dl (4.4 to 6.1 mmol/l) or standard insulin therapy to maintain glucose levels between 180 and 200 mg/dl (10 and 11.1 mmol/l). The primary end point was mortality at 28 days. Results Over a period of 30 months, 504 patients were enrolled. The 28-day mortality rate was 32.4% (81 of 250) in the standard insulin therapy group and 36.6% (93 of 254) in the intensive insulin therapy group (Relative Risk [RR]: 1.1; 95% confidence interval [CI]: 0.85 to 1.42). The ICU mortality in the standard insulin therapy group was 31.2% (78 of 250) and 33.1% (84 of 254) in the intensive insulin therapy group (RR: 1.06; 95%CI: 0.82 to 1.36). There was no statistically significant reduction in the rate of ICU-acquired infections: 33.2% in the standard insulin therapy group compared with 27.17% in the intensive insulin therapy group (RR: 0.82; 95%CI: 0.63 to 1.07). The rate of hypoglycaemia (≤ 40 mg/dl) was 1.7% in the standard insulin therapy group and 8.5% in the intensive insulin therapy group (RR: 5.04; 95% CI: 1.20 to 21.12). Conclusions IIT used to maintain glucose levels within normal limits did not reduce morbidity or mortality of patients admitted to a mixed medical/surgical ICU. Furthermore, this therapy increased the risk of hypoglycaemia. Trial Registration clinicaltrials.gov Identifiers: 4374-04-13031; 094-2 in 000966421 PMID:18799004

Management of type 2 diabetes with Fixed-Ratio combination insulin degludec/liraglutide (IDEGLIRA) versus Basal-Bolus therapy (INSULIN GLARGINE U100 PLUS INSULIN ASPART): A Short-Term Cost-Effectiveness analysis in the UK setting.

PubMed

Drummond, R S; Malkin, Sjp; Du Preez, M; Lee, X Y; Hunt, B

2018-05-24

Insulin degludec/liraglutide (IDegLira) is a once-daily, single-injection, fixed-ratio combination of insulin degludec, a basal insulin with a half-life of more than 24 hours, and GLP-1 receptor agonist liraglutide. The present analysis evaluated the cost-effectiveness of IDegLira versus basal-bolus therapy (BBT) with insulin glargine U100 plus up to four times daily insulin aspart for management of type 2 diabetes in the UK. A Microsoft Excel model was used to evaluate the cost-utility of IDegLira versus BBT over a 1-year time horizon. Clinical input data were taken from the treat-to-target DUAL VII trial, conducted in patients unable to achieve adequate glycaemic control (Hb A1c <7.0%) with basal insulin, with IDegLira associated with lower rates of hypoglycaemia and reduced body mass index (BMI) in comparison with BBT, with similar Hb A1c reductions. Costs (GBP) and event-related disutilities were taken from published sources. Extensive sensitivity analyses were performed. IDegLira was associated with an improvement of 0.05 quality-adjusted life years (QALYs) versus BBT, due to reductions in non-severe hypoglycaemic episodes and BMI with IDegLira. Costs were higher with IDegLira by GBP 303 per patient, leading to an incremental cost-effectiveness ratio (ICER) of GBP 5,924 per QALY gained for IDegLira versus BBT. ICERs remained below GBP 20,000 per QALY gained across a range of sensitivity analyses. IDegLira is a cost-effective alternative to BBT with insulin glargine U100 plus insulin aspart, providing equivalent glycaemic control with a simpler treatment regimen for patients with type 2 diabetes inadequately controlled on basal insulin in the UK. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Management of the pregnant, insulin-dependent diabetic woman.

PubMed

Jovanovic, L; Peterson, C M

1980-01-01

An intensive care program was offered to all insulin-dependent, pregnant diabetic women who presented to The New York Hospital Obstetrical Clinic in their eighth week or less of gestation. The patients were hospitalized for 1 wk to normalize their blood glucose and to teach the technique of self-monitored glucose determination, diet and exchange lists, and the method to titrate insulin according to the blood glucose determination. The mean blood glucose for the first 10 patients accepted to the program was 169 mg/dl at the start of the program with a mean hemoglobin A1c of 9.4% for the group (normal < 5.5%) and glucosuria up to 50 g/24 h. After discharge, mean glucose was 91 mg/dl, and urinary glucose excretion was 1.4 g/24 h. HbA1c fell into the normal range 5 wk after normoglycemia was achieved (3.4%) (nl < 5.5%). Normoglycemia was maintained as outpatients until 3 wk before delivery when the patients were readmitted for tests of fetal well-being. Mean weight gain for the mothers was 12.2 kg. Mean glucose at delivery was 87 mg/dl and HbA1c was 3%. Hormonal profiles (hCG, hPRL, estrogens, progesterone, hPL) normalized after normoglycemia was achieved and remained normal until delivery. Mean gestational age at time of delivery was 38.8 wk with a mean infant birth weight of 2988 g. No infant manifested hypoglycemia, hypocalcemia, erythremia, or respiratory disease. The use of self-monitored blood glucose allows for optimal care of the insulin-dependent, pregnant diabetic woman while she remains at home with her family.

Concepts and clinical use of ultra-long basal insulin.

PubMed

Eliaschewitz, Freddy Goldberg; Barreto, Tânia

2016-01-01

Diabetes mellitus (DM) is a public health issue, affecting around 382 million people worldwide. In order to achieve glycemic goals, insulin therapy is the frontline therapy for type 1 DM patients; for patients with type 2 DM, use of insulin therapy is an option as initial or add-on therapy for those not achieving glycemic control. Despite insulin therapy developments seen in the last decades, several barriers remain for insulin initiation and optimal maintenance in clinical practice. Fear of hypoglycemia, weight gain, pain associated with blood testing and injection-related pain are the most cited reasons for not starting insulin therapy. However, new generation of basal insulin formulations, with longer length of action, have shown the capability of providing adequate glycemic control with lower risk of hypoglycemia.

Carbohydrate Modified Diet & Insulin Sensitizers Reduce Body Weight & Modulate Metabolic Syndrome Measures in EMPOWIR (Enhance the Metabolic Profile of Women with Insulin Resistance): A Randomized Trial of Normoglycemic Women with Midlife Weight Gain

PubMed Central

Mogul, Harriette R.; Freeman, Ruth; Nguyen, Khoa; Frey, Michael; Klein, Lee-Ann; Jozak, Sheila; Tanenbaum, Karen

2014-01-01

Rationale Progressive midlife weight gain is associated with multiple adverse health outcomes and may represent an early manifestation of insulin resistance in a distinct subset of women. Emerging data implicate hyperinsulinema as a proximate cause of weight gain and support strategies that attenuate insulin secretion. Objective To assess a previously reported novel hypocaloric carbohydrate modified diet alone (D), and in combination with metformin (M) and metformin plus low-dose rosiglitazone (MR), in diverse women with midlife weight gain (defined as >20lbs since the twenties), normal glucose tolerance, and hyperinsulinemia. Participants 46 women, mean age 46.6±1.0, BMI 30.5±0.04 kg/m2, 54.5% white, 22.7% black, 15.9% Hispanic, at 2 university medical centers. Methods A dietary intervention designed to reduce insulin excursions was implemented in 4 weekly nutritional group workshops prior to randomization. Main Outcome Measure Change in 6-month fasting insulin. Pre-specified secondary outcomes were changes in body weight, HOMA-IR, metabolic syndrome (MS) measures, leptin, and adiponectin. Results Six-month fasting insulin declined significantly in the M group: 12.5 to 8.0 µU/ml, p = .026. Mean 6-month weight decreased significantly and comparably in D, M, and MR groups: 4.7, 5.4, and 5.5% (p’s.049, .002, and.032). HOMA–IR decreased in M and MR groups (2.5 to 1.6 and 1.9 to 1.3, p’s = .054, .013). Additional improvement in MS measures included reduced waist circumference in D and MR groups and increased HDL in the D and M groups. Notably, mean fasting leptin did not decline in a subset of subjects with weight loss (26.15±2.01 ng/ml to 25.99±2.61 ng/ml, p = .907. Adiponectin increased significantly in the MR group (11.1±1.0 to 18.5±7.4, p<.001) Study medications were well tolerated. Conclusions These findings suggest that EMPOWIR’s easily implemented dietary interventions, alone and in combination with pharmacotherapies that target hyperinsulinemia, merit additional investigation in larger, long-term studies. Trial Registration ClinicalTrials.gov NCT00618072 PMID:25259787

Adipose tissue (P)RR regulates insulin sensitivity, fat mass and body weight.

PubMed

Shamansurova, Zulaykho; Tan, Paul; Ahmed, Basma; Pepin, Emilie; Seda, Ondrej; Lavoie, Julie L

2016-10-01

We previously demonstrated that the handle-region peptide, a prorenin/renin receptor [(P)RR] blocker, reduces body weight and fat mass and may improve insulin sensitivity in high-fat fed mice. We hypothesized that knocking out the adipose tissue (P)RR gene would prevent weight gain and insulin resistance. An adipose tissue-specific (P)RR knockout (KO) mouse was created by Cre-loxP technology using AP2-Cre recombinase mice. Because the (P)RR gene is located on the X chromosome, hemizygous males were complete KO and had a more pronounced phenotype on a normal diet (ND) diet compared to heterozygous KO females. Therefore, we challenged the female mice with a high-fat diet (HFD) to uncover certain phenotypes. Mice were maintained on either diet for 9 weeks. KO mice had lower body weights compared to wild-types (WT). Only hemizygous male KO mice presented with lower total fat mass, higher total lean mass as well as smaller adipocytes compared to WT mice. Although food intake was similar between genotypes, locomotor activity during the active period was increased in both male and female KO mice. Interestingly, only male KO mice had increased O2 consumption and CO2 production during the entire 24-hour period, suggesting an increased basal metabolic rate. Although glycemia during a glucose tolerance test was similar, KO males as well as HFD-fed females had lower plasma insulin and C-peptide levels compared to WT mice, suggesting improved insulin sensitivity. Remarkably, all KO animals exhibited higher circulating adiponectin levels, suggesting that this phenotype can occur even in the absence of a significant reduction in adipose tissue weight, as observed in females and, thus, may be a specific effect related to the (P)RR. (P)RR may be an important therapeutic target for the treatment of obesity and its associated complications such as type 2 diabetes.

Combining insulin with metformin or an insulin secretagogue in non-obese patients with type 2 diabetes: 12 month, randomised, double blind trial

PubMed Central

Tarnow, Lise; Frandsen, Merete; Nielsen, Bente B; Hansen, Birgitte V; Pedersen, Oluf; Parving, Hans-Henrik; Vaag, Allan A

2009-01-01

Objectives To study the effect of insulin treatment in combination with metformin or an insulin secretagogue, repaglinide, on glycaemic regulation in non-obese patients with type 2 diabetes. Design Randomised, double blind, double dummy, parallel trial. Setting Secondary care in Denmark between 2003 and 2006. Participants Non-obese patients (BMI ≤27) with preserved beta cell function. Interventions After a four month run-in period with repaglinide plus metformin combination therapy, patients with a glycated haemoglobin (HbA1c) concentration of 6.5% or more were randomised to repaglinide 6 mg or metformin 2000 mg. All patients also received biphasic insulin aspart 70/30 (30% soluble insulin aspart and 70% intermediate acting insulin aspart) 6 units once a day before dinner for 12 months. Insulin dose was adjusted aiming for a fasting plasma glucose concentration of 4.0-6.0 mmol/l. The target of HbA1c concentration was less than 6.5%. Treatment was intensified to two or three insulin injections a day if glycaemic targets were not reached. Main outcome measure HbA1c concentration. Results Of the 459 patients who were eligible, 102 were randomised, and 97 completed the trial. Patients had had type 2 diabetes for approximately 10 years. At the end of treatment, HbA1c concentration was reduced by a similar amount in the two treatment groups (insulin plus metformin: mean (standard deviation) HbA1c 8.15% (1.32) v 6.72% (0.66); insulin plus repaglinide: 8.07% (1.49) v 6.90% (0.68); P=0.177). Total daily insulin dose and risk of hypoglycaemia were also similar in the two treatment groups. Weight gain was less with metformin plus biphasic insulin aspart 70/30 than with repaglinide plus biphasic insulin aspart 70/30 (difference in mean body weight between treatments −2.51 kg, 95% confidence interval −4.07 to −0.95). Conclusions In non-obese patients with type 2 diabetes and poor glycaemic regulation on oral hypoglycaemic agents, overall glycaemic regulation with insulin in combination with metformin was equivalent to that with insulin plus repaglinide. Weight gain seemed less with insulin plus metformin than with insulin plus repaglinide. Trial registration NCT00118963 PMID:19900993

Hormonal and metabolic effects of olanzapine and clozapine related to body weight in rodents.

PubMed

Albaugh, Vance L; Henry, Cathy R; Bello, Nicholas T; Hajnal, Andras; Lynch, Susan L; Halle, Beth; Lynch, Christopher J

2006-01-01

To characterize a model of atypical antipsychotic drug-induced obesity and evaluate its mechanism. Chronically, olanzapine or clozapine was self-administered via cookie dough to rodents (Sprague-Dawley or Wistar rats; C57Bl/6J or A/J mice). Chronic studies measured food intake, body weight, adiponectin, active ghrelin, leptin, insulin, tissue wet weights, glucose, clinical chemistry endpoints, and brain dopaminergic D2 receptor density. Acute studies examined food intake, ghrelin, leptin, and glucose tolerance. Olanzapine (1 to 8 mg/kg), but not clozapine, increased body weight in female rats only. Weight changes were detectable within 2 to 3 days and were associated with hyperphagia starting approximately 24 hours after the first dose. Chronic administration (12 to 29 days) led to adiposity, hyperleptinemia, and mild insulin resistance; no lipid abnormalities or changes in D2 receptor density were observed. Topiramate, which has reversed weight gain from atypical antipsychotics in humans, attenuated weight gain in rats. Acutely, olanzapine, but not clozapine, lowered plasma glucose and leptin. Increases in glucose, insulin, and leptin following a glucose challenge were also blunted. A model of olanzapine-induced obesity was characterized which shares characteristics of patients with atypical antipsychotic drug-induced obesity; these characteristics include hyperphagia, hyperleptinemia, insulin resistance, and weight gain attenuation by topiramate. This model may be a useful and inexpensive model of uncomplicated obesity amenable to rapid screening of weight loss drugs. Olanzapine-induced weight gain may be secondary to hyperphagia associated with acute lowering of plasma glucose and leptin, as well as the inability to increase plasma glucose and leptin following a glucose challenge.

Over-expression of ZnT7 increases insulin synthesis and secretion in pancreatic beta-cells by promoting insulin gene transcription

USDA-ARS?s Scientific Manuscript database

The mechanism by which zinc regulates insulin synthesis and secretion in pancreatic beta-cells is still unclear. Cellular zinc homeostasis is largely maintained by zinc transporters and intracellular zinc binding proteins. In this study, we demonstrated that zinc transporter 7 (ZnT7, Slc30a7) was co...

Establishment of rat pancreatic endocrine cell lines by infection with simian virus 40.

PubMed Central

Niesor, E J; Wollheim, C B; Mintz, D H; Blondel, B; Renold, A E; Weil, R

1979-01-01

The feasibility of infection and transformation by SV40 (simian virus 40) of primary cell cultures derived from newborn-rat pancreas was investigated. As judged by the presence of intranuclear SV40 T-antigen, exposure to the virus resulted specifically in infection and transformation of epithelioid (predominantly endocrine) cells. The transformed cells were subcultured (more than 64 passages) and cloned. Culture medium and acid/ethanol extracts of the cells did not contain detectable amounts of immunoreactive insulin after the third subculture. However, inoculation of such SV40-transformed pancreatic cells into immunodeficient rats results in tumours in which insulin production was partially restored through the passage in vivo, since the tumour cells contained and synthesized small amounts of immunoreactive insulin which co-migrated with an insulin marker on gel chromatography. Interestingly, the transformed cells maintained under tissue-culture conditions produced a protein immunologically related to insulin, soluble in aqueous buffer but insoluble in acid/ethanol. This 3000-dalton protein is too large to be a translation product of the rat preproinsulin 9S mRNA. SV40-transformed pancreatic cells might prove useful in the investigation of the factors controlling and maintaining insulin biosynthesis. Images Fig. 1. PMID:222255

Disruption of growth hormone receptor gene causes diminished pancreatic islet size and increased insulin sensitivity in mice.

PubMed

Liu, Jun-Li; Coschigano, Karen T; Robertson, Katie; Lipsett, Mark; Guo, Yubin; Kopchick, John J; Kumar, Ujendra; Liu, Ye Lauren

2004-09-01

Growth hormone, acting through its receptor (GHR), plays an important role in carbohydrate metabolism and in promoting postnatal growth. GHR gene-deficient (GHR(-/-)) mice exhibit severe growth retardation and proportionate dwarfism. To assess the physiological relevance of growth hormone actions, GHR(-/-) mice were used to investigate their phenotype in glucose metabolism and pancreatic islet function. Adult GHR(-/-) mice exhibited significant reductions in the levels of blood glucose and insulin, as well as insulin mRNA accumulation. Immunohistochemical analysis of pancreatic sections revealed normal distribution of the islets despite a significantly smaller size. The average size of the islets found in GHR(-/-) mice was only one-third of that in wild-type littermates. Total beta-cell mass was reduced 4.5-fold in GHR(-/-) mice, significantly more than their body size reduction. This reduction in pancreatic islet mass appears to be related to decreases in proliferation and cell growth. GHR(-/-) mice were different from the human Laron syndrome in serum insulin level, insulin responsiveness, and obesity. We conclude that growth hormone signaling is essential for maintaining pancreatic islet size, stimulating islet hormone production, and maintaining normal insulin sensitivity and glucose homeostasis.

Neuroendocrine mechanism of food intake and energy regulation in Japanese quail under differential simulated photoperiodic conditions: Involvement of hypothalamic neuropeptides, AMPK, insulin and adiponectin receptors.

PubMed

Banerjee, Somanshu; Chaturvedi, Chandra Mohini

2018-05-26

Neuroendocrine coordination between the reproductive and energy regulatory hypothalamic circuitries not only tightly regulates food intake and energy expenditure but also maintains the body weight and reproduction. The effect of different simulated photoperiodic conditions on food intake and neuroendocrine mechanism of energy homeostasis in Japanese quail is not investigated till date. Hence, our present study is designed to elucidate the effect of different simulated photoperiodic conditions on food consumption and neuroendocrine mechanism(s) of energy regulation in this poultry species. The alterations in hypothalamic energy balancing neuropeptides (NPY/AgRP/CART), polypeptide hormone precursor (POMC), protein kinase (AMPK-p-AMPK) as well as receptors of insulin and adiponectin [Insulin Receptor (IR), Adiponectin Receptor 1 & 2] have been investigated in photosensitive (PS), scotorefractory (SR),photorefractory (PR) and scotosensitive (SS) quail. Immunofluorescence and western blotting were used to quantify the expression of these peptides and proteins. Results showed increased food consumption and body weight gain, along with increased expression of NPY, AgRP, IR, adiponectin receptors and p-AMPK, decreased CART and POMC in the hypothalamus of photosensitive and scotorefractory quail. While, opposite findings were observed in photorefractory and scotosensitive quail. Hence, this study may suggest the hypothalamic energy channelization towards reproductive axis in photosensitive and scotorefractory quail to support the full breeding conditions, while hypothalamic energy deprivation in photorefractory and scotosensitive quail leads to reproductive quiescence. Copyright © 2018 Elsevier B.V. All rights reserved.

Return of hunger following a relatively high carbohydrate breakfast is associated with earlier recorded glucose peak and nadir

PubMed Central

Chandler-Laney, Paula C.; Morrison, Shannon A.; Goree, Laura Lee T.; Ellis, Amy C.; Casazza, Krista; Desmond, Renee; Gower, Barbara A

2014-01-01

Objective To test the hypothesis that a breakfast meal with high carbohydrate/ low fat results in an earlier increase in postprandial glucose and insulin, a greater decrease below baseline in postprandial glucose, and an earlier return of appetite, compared to a low carbohydrate/high fat meal. Design Overweight but otherwise healthy adults (n=64) were maintained on one of two eucaloric diets: high carbohydrate/low fat (HC/LF; 55:27:18% kcals from carbohydrate: fat: protein) versus low carbohydrate/high fat (LC/HF; 43:39:18% kcals from carbohydrate: fat: protein). After 4 weeks of acclimation to the diets, participants underwent a meal test during which circulating glucose and insulin and self-reported hunger and fullness, were measured before and after consumption of breakfast from their assigned diets. Results The LC/HF meal resulted in a later time at the highest and lowest recorded glucose, higher glucose concentrations at 3 and 4 hours post-meal, and lower insulin incremental area under the curve. Participants consuming the LC/HF meal reported lower appetite 3 and 4 hours following the meal, a response that was associated with the timing of the highest and lowest recorded glucose. Conclusions Modest increases in meal carbohydrate content at the expense of fat content may facilitate weight gain over the long-term by contributing to an earlier rise and fall of postprandial glucose concentrations and an earlier return of appetite. PMID:24819342

The temporal impact of chronic intermittent psychosocial stress on high-fat diet-induced alterations in body weight.

PubMed

Finger, Beate C; Dinan, Timothy G; Cryan, John F

2012-06-01

Chronic stress and diet can independently or in concert influence the body's homeostasis over time. Thus, it is crucial to investigate the interplay of these parameters to gain insight into the evolution of stress-induced metabolic and eating disorders. C57BL/6J mice were subjected to chronic psychosocial (mixed model of social defeat and overcrowding) stress in combination with either a high- or low-fat diet for three or six weeks. To determine the evolution of stress and dietary effects, changes in body weight, caloric intake and caloric efficiency were determined as well as circulating leptin, insulin, glucose and corticosterone levels and social avoidance behaviour. Exposure to stress for three weeks caused an increase in weight gain, in caloric intake and in caloric efficiency only in mice on a low-fat diet. However, after six weeks, only stressed mice on a high-fat diet displayed a pronounced inhibition of body weight gain, accompanied by reduced caloric intake and caloric efficiency. Stress decreased circulating leptin levels in mice on a low-fat diet after three weeks and in mice on a high-fat diet after three and six weeks of exposure. Plasma levels of insulin and markers of insulin resistance were blunted in mice on high-fat diet following six weeks of stress exposure. Social avoidance following chronic stress was present in all mice after three and six weeks. This study describes the evolution of the chronic effects of social defeat/overcrowding stress in combination with exposure to high- or low-fat diet. Most importantly, we demonstrate that a six week chronic exposure to social defeat stress prevents the metabolic effects of high-fat diet, by inhibiting an increase in weight gain, caloric intake and efficiency and insulin resistance as well as in plasma leptin and insulin levels. This study highlights the importance of considering the chronic aspects of both parameters and their time-dependent interplay. Copyright © 2011 Elsevier Ltd. All rights reserved.

Energy balance and hypothalamic effects of a high-protein/low-carbohydrate diet.

PubMed

Kinzig, Kimberly P; Hargrave, Sara L; Hyun, Jayson; Moran, Timothy H

2007-10-22

Diets high in fat or protein and extremely low in carbohydrate are frequently reported to result in weight loss in humans. We previously reported that rats maintained on a low-carbohydrate-high fat diet (LC-HF) consumed similar kcals/day as chow (CH)-fed rats and did not differ in body weight after 7 weeks. LC-HF rats had a 45% decrease in POMC expression in the ARC, decreased plasma insulin, and increased plasma leptin and ghrelin. In the present study we assessed the effects of a low-carbohydrate-high-protein diet (HP: 30% fat, 65% protein, and 5% CHO) on body weight, caloric intake, plasma hormone levels and hypothalamic gene expression. Male rats (n=16) were maintained on CH or HP for 4 weeks. HP rats gained significantly less weight than CH rats (73.4+/-9.4 and 125.0+/-8.2 g) and consumed significantly less kcals/day (94.8+/-1.5 and 123.6+/-1.1). Insulin was significantly reduced in HP rats (HP: 1.8+/-0.6 vs. CH: 4.12+/-0.8 ng/ml), there were no differences between groups in plasma leptin and plasma ghrelin was significantly elevated in HP rats (HP: 127.5+/-45 vs. CH: 76.9+/-8 pg/ml). Maintenance on HP resulted in significantly increased ARC POMC (HP: 121+/-10.0 vs. 100+/-5.9) and DMH NPY (HP: 297+/-82.1 vs. CH: 100+/-37.7) expression compared to CH controls. These data suggest that the macronutrient content of diets differentially influences hypothalamic gene expression in ways that can affect overall intake.

Personalized intensification of insulin therapy in type 2 diabetes - does a basal-bolus regimen suit all patients?

PubMed

Giugliano, D; Sieradzki, J; Stefanski, A; Gentilella, R

2016-08-01

Many patients with type 2 diabetes mellitus (T2DM) require insulin therapy. If basal insulin fails to achieve glycemic control, insulin intensification is one possible treatment intensification strategy. We summarized clinical data from randomized clinical trials designed to compare the efficacy and safety of basal-bolus and premixed insulin intensification regimens. We defined a between-group difference of ≥0.3% in end-of-study glycated hemoglobin (HbA1c) as clinically meaningful. A PubMed database search supplemented by author-identified papers yielded 15 trials which met selection criteria: randomized design, patients with T2DM receiving basal-bolus (bolus injection ≤3 times/day) vs. premixed (≤3 injections/day) insulin regimens, primary/major endpoint(s) HbA1c- and/or hypoglycemia-related, and trial duration ≥12 weeks. Glycemic control improved with both basal-bolus and premixed insulin regimens with - in most cases - acceptable levels of weight gain and hypoglycemia. A clinically meaningful difference between regimens in glycemic control was recorded in only four comparisons, all of which favored basal-bolus therapy. The incidence of hypoglycemia was significantly different between regimens in only three comparisons, one of which favored premixed insulin and two basal-bolus therapy. Of the four trials that reported a significant difference between regimens in bodyweight change, two favored basal-bolus therapy and two favored premixed insulin. Thus, on a population level, neither basal-bolus therapy nor premixed insulin showed a consistent advantage in terms of glycemic control, hypoglycemic risk, or bodyweight gain. It is therefore recommended that clinicians should adopt an individualized approach to insulin intensification - taking into account the benefits and risks of each treatment approach and the attitude and preferences of each patient - in the knowledge that both basal-bolus and premixed regimens may be successful.

Glycaemic control and hypoglycaemia with new insulin glargine 300 U/ml versus insulin glargine 100 U/ml in people with type 2 diabetes using basal insulin and oral antihyperglycaemic drugs: the EDITION 2 randomized 12-month trial including 6-month extension.

PubMed

Yki-Järvinen, H; Bergenstal, R M; Bolli, G B; Ziemen, M; Wardecki, M; Muehlen-Bartmer, I; Maroccia, M; Riddle, M C

2015-12-01

To compare the efficacy and safety of new insulin glargine 300 U/ml (Gla-300) with insulin glargine 100 U/ml (Gla-100) over 12 months of treatment in people with type 2 diabetes using basal insulin and oral antihyperglycaemic drugs (OADs). EDITION 2 (NCT01499095) was a randomized, 6-month, multicentre, open-label, two-arm, phase IIIa study investigating once-daily Gla-300 versus Gla-100, plus OADs (excluding sulphonylureas), with a 6-month safety extension. Similar numbers of participants in each group completed 12 months of treatment [Gla-300, 315 participants (78%); Gla-100, 314 participants (77%)]. The reduction in glycated haemoglobin was maintained for 12 months with both treatments: least squares (LS) mean (standard error) change from baseline -0.55 (0.06)% for Gla-300 and -0.50 (0.06)% for Gla-100; LS mean difference -0.06 [95% confidence interval (CI) -0.22 to 0.10)%]. A significant relative reduction of 37% in the annualized rate of nocturnal confirmed [≤3.9 mmol/l (≤70 mg/dl)] or severe hypoglycaemia was observed with Gla-300 compared with Gla-100: rate ratio 0.63 [(95% CI 0.42-0.96); p = 0.031], and fewer participants experienced ≥1 event [relative risk 0.84 (95% CI 0.71-0.99)]. Severe hypoglycaemia was infrequent. Weight gain was significantly lower with Gla-300 than Gla-100 [LS mean difference -0.7 (95% CI -1.3 to -0.2) kg; p = 0.009]. Both treatments were well tolerated with a similar pattern of adverse events (incidence of 69 and 60% in the Gla-300 and Gla-100 groups). In people with type 2 diabetes treated with Gla-300 or Gla-100, and non-sulphonylurea OADs, glycaemic control was sustained over 12 months, with less nocturnal hypoglycaemia in the Gla-300 group. © 2015 The Authors. Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.

Effect of antipsychotics on peptides involved in energy balance in drug-naive psychotic patients after 1 year of treatment.

PubMed

Perez-Iglesias, Rocio; Vazquez-Barquero, Jose Luis; Amado, Jose Antonio; Berja, Ana; Garcia-Unzueta, Maria Teresa; Pelayo-Terán, Jose María; Carrasco-Marín, Eugenio; Mata, Ignacio; Crespo-Facorro, Benedicto

2008-06-01

Weight gain has become one of the most common and concerning side effects of antipsychotic treatment. The mechanisms whereby antipsychotics induce weight gain are not known. It has been suggested that peptides related to food intake and energy balance could play a role in weight gain secondary to antipsychotic therapy. To better understand the pathophysiology of antipsychotic-induced weight gain, we studied the effects of 3 antipsychotic drugs (haloperidol, olanzapine, and risperidone) on peptides involved in energy balance (insulin, ghrelin, leptin, adiponectin, visfatin, and resistin) in a population of drug-naive patients with first episode of psychosis.A significant increase in weight (10.16 kg [SD, 8.30 kg]; P < 0.001), body mass index (3.56 kg/m [SD, 2.89 kg/m]; P < 0.001), and fasting insulin (3.93 muU/mL [SD, 3.93 muU/mL]; P = 0.028), leptin (6.76 ng/mL [SD, 7.21 ng/mL]; P < 0.001), and ghrelin (15.47 fmol/mL [SD, 47.90 fmol/mL]; P = 0.009) plasma levels were observed. The increments in insulin and leptin concentrations were highly correlated with the increment in weight and body mass index and seem to be a consequence of the higher fat stores. The unexpected increase in ghrelin levels might be related with the causal mechanism of weight gain induced by antipsychotics. Finally, the 3 antipsychotics had similar effects in all parameters evaluated.

Adipose tissue inflammation and reduced insulin sensitivity in ovariectomized mice occurs in the absence of increased adiposity

USDA-ARS?s Scientific Manuscript database

Menopause promotes central obesity, adipose tissue (AT) inflammation and insulin resistance (IR). Both obesity and the loss of estrogen can activate innate and adaptive immune cells (macrophages (M's), T-cells). The respective impacts of weight gain and loss of ovarian hormones on AT inflammation an...

Zinc transporter 7 deficiency affects lipid synthesis in adipocytes by inhibiting insulin-dependent Akt activity and glucose uptake

USDA-ARS?s Scientific Manuscript database

Mice deficient for zinc transporter 7 (Znt7) are mildly zinc deficient, accompanied with low body weight gain and body fat accumulation. To investigate the underlying mechanism of Znt7 deficiency in body adiposity, we investigated fatty acid composition and insulin sensitivity in visceral (epididyma...

An acute rat in vivo screening model to predict compounds that alter blood glucose and/or insulin regulation.

PubMed

Brott, David A; Diamond, Melody; Campbell, Pam; Zuvich, Andy; Cheatham, Letitia; Bentley, Patricia; Gorko, Mary Ann; Fikes, James; Saye, JoAnne

2013-01-01

Drug-induced glucose dysregulation and insulin resistance have been associated with weight gain and potential induction and/or exacerbation of diabetes mellitus in the clinic suggesting they may be safety biomarkers when developing antipsychotics. Glucose and insulin have also been suggested as potential efficacy biomarkers for some oncology compounds. The objective of this study was to qualify a medium throughput rat in vivo acute Intravenous Glucose Tolerance Test (IVGTT) for predicting compounds that will induce altered blood glucose and/or insulin levels. Acute and sub-chronic studies were performed to qualify an acute IVGTT model. Double cannulated male rats (Han-Wistar and Sprague-Dawley) were administered vehicle, olanzapine, aripiprazole or other compounds at t=-44min for acute studies and at time=-44min on the last day of dosing for sub-chronic studies, treated with dextrose (time=0min; i.v.) and blood collected using an automated Culex® system for glucose and insulin analysis (time=-45, -1, 2, 10, 15, 30, 45, 60, 75, 90, 120, 150 and 180min). Olanzapine significantly increased glucose and insulin area under the curve (AUC) values while aripiprazole AUC values were similar to control, in both acute and sub-chronic studies. All atypical antipsychotics evaluated were consistent with literature references of clinical weight gain. As efficacy biomarkers, insulin AUC but not glucose AUC values were increased with a compound known to have insulin growth factor-1 (IGF-1) activity, compared to control treatment. These studies qualified the medium throughput acute IVGTT model to more quickly screen compounds for 1) safety - the potential to elicit glucose dysregulation and/or insulin resistance and 2) efficacy - as a surrogate for compounds affecting the glucose and/or insulin regulatory pathways. These data demonstrate that the same in vivo rat model and assays can be used to predict both clinical safety and efficacy of compounds. © 2013.

Hormonal and Metabolic Effects of Olanzapine and Clozapine Related to Body Weight in Rodents

PubMed Central

Albaugh, Vance L.; Henry, Cathy R.; Bello, Nicholas T.; Hajnal, Andras; Lynch, Susan L.; Halle, Beth; Lynch, Christopher J.

2009-01-01

Objective To characterize a model of atypical antipsychotic drug-induced obesity and evaluate its mechanism. Research Methods and Procedures Chronically, olanzapine or clozapine was self-administered via cookie dough to rodents (Sprague-Dawley or Wistar rats; C57Bl/6J or A/J mice). Chronic studies measured food intake, body weight, adiponectin, active ghrelin, leptin, insulin, tissue wet weights, glucose, clinical chemistry endpoints, and brain dopaminergic D2 receptor density. Acute studies examined food intake, ghrelin, leptin, and glucose tolerance. Results Olanzapine (1 to 8 mg/kg), but not clozapine, increased body weight in female rats only. Weight changes were detectable within 2 to 3 days and were associated with hyperphagia starting ~24 hours after the first dose. Chronic administration (12 to 29 days) led to adiposity, hyperleptinemia, and mild insulin resistance; no lipid abnormalities or changes in D2 receptor density were observed. Topiramate, which has reversed weight gain from atypical anti-psychotics in humans, attenuated weight gain in rats. Acutely, olanzapine, but not clozapine, lowered plasma glucose and leptin. Increases in glucose, insulin, and leptin following a glucose challenge were also blunted. Discussion A model of olanzapine-induced obesity was characterized which shares characteristics of patients with atypical antipsychotic drug-induced obesity; these characteristics include hyperphagia, hyperleptinemia, insulin resistance, and weight gain attenuation by topiramate. This model may be a useful and inexpensive model of uncomplicated obesity amenable to rapid screening of weight loss drugs. Olanzapine-induced weight gain may be secondary to hyperphagia associated with acute lowering of plasma glucose and leptin, as well as the inability to increase plasma glucose and leptin following a glucose challenge. PMID:16493121

Effects of Exenatide Plus Rosiglitazone on β-Cell Function and Insulin Sensitivity in Subjects With Type 2 Diabetes on Metformin

PubMed Central

DeFronzo, Ralph A.; Triplitt, Curtis; Qu, Yongming; Lewis, Michelle S.; Maggs, David; Glass, Leonard C.

2010-01-01

OBJECTIVE Study the effects of exenatide (EXE) plus rosiglitazone (ROSI) on β-cell function and insulin sensitivity using hyperglycemic and euglycemic insulin clamp techniques in participants with type 2 diabetes on metformin. RESEARCH DESIGN AND METHODS In this 20-week, randomized, open-label, multicenter study, participants (mean age, 56 ± 10 years; weight, 93 ± 16 kg; A1C, 7.8 ± 0.7%) continued their metformin regimen and received either EXE 10 μg b.i.d. (n = 45), ROSI 4 mg b.i.d. (n = 45), or EXE 10 μg b.i.d. + ROSI 4 mg b.i.d. (n = 47). Seventy-three participants underwent clamp procedures to quantitate insulin secretion and insulin sensitivity. RESULTS A1C declined in all groups (P < 0.05), but decreased most with EXE+ROSI (EXE+ROSI, −1.3 ± 0.1%; ROSI, −1.0 ± 0.1%, EXE, −0.9 ± 0.1%; EXE+ROSI vs. EXE or ROSI, P < 0.05). ROSI resulted in weight gain, while EXE and EXE+ROSI resulted in weight loss (EXE, −2.8 ± 0.5 kg; EXE+ROSI, −1.2 ± 0.5 kg; ROSI, + 1.5 ± 0.5 kg; P < 0.05 between and within all groups). At week 20, 1st and 2nd phase insulin secretion was significantly higher in EXE and EXE+ROSI versus ROSI (both P < 0.05). Insulin sensitivity (M value) was significantly higher in EXE+ROSI versus EXE (P = 0.014). CONCLUSIONS Therapy with EXE+ROSI offset the weight gain observed with ROSI and elicited an additive effect on glycemic control with significant improvements in β-cell function and insulin sensitivity. PMID:20107105

A Study of the Carbohydrate-to-Insulin Ratio in Pregnant Women with Type 1 Diabetes on Pump Treatment.

PubMed

Bongiovanni, Marzia; Fresa, Raffaella; Visalli, Natalia; Bitterman, Olimpia; Suraci, Concetta; Napoli, Angela

2016-06-01

The aim of this study was to assess carbohydrate (CHO)-to-insulin ratio (CHO/IR) values in pregnant women with type 1 diabetes and to describe differences in CHO/IR across each week of pregnancy. This was a multicenter, retrospective, observational study (2006-2012) of 101 white pregnant women with a mean age of 32 (range, 18-43) years who had type 1 diabetes and were under continuous subcutaneous insulin infusion (CSII) therapy. These patients had the following characteristics: type 1 diabetes duration was 1 year (range, 1-31 years), the pregestational glycosylated hemoglobin level was 6.9% (range, 6.8-12.1%), the median weight gain during pregnancy was 14 kg (-3; 25 kg), with delivery at 37 weeks (range, 30-40 weeks), and the child had a birth weight of 3.530 kg (range, 1.480-5.250 kg). The CHO/IR was measured by dividing the CHO (in g) of each meal by insulin unit injected to acquire and maintain the following glycemic targets: fasting <90 mg/dL and 1-h postprandial <130 mg/dL. Simultaneously, CHO/IR indices were calculated through 500/total daily doses of insulin and 300/total daily doses of insulin. Education and management before and during pregnancy were in agreement with Italian Association of Dietitians, Association of Medical Diabetologists, and Italian Society of Diabetology recommendations. Data were analyzed using SPSS software (version 20.0; SPSS, Inc., Chicago, IL). The CHO/IR decreased on average from 9.6 (5-18) to 5.4 (2.3-8) at breakfast, from 10 (3.5-16) to 8.4 (3.0-17.8) at lunch, and from 12.5 (8-20) to 6.1 (4.2-12) at dinner. The CHO/IR calculated using the "500 rule" decreased from 14.3 (10-20.3) to 8.6 (4.1-15.9). Using the "300 rule," the ratios decreased from 8.5 (6-12.1) to 5.2 (2.4-9.5). The bivariate correlation between the values calculated more appropriate values using the "300 rule" for breakfast and the "500 rule" for lunch and dinner across all weeks of pregnancy. CHO/IR reduction in pregnancy is likely due to an increase in insulin resistance.

Effects of saxagliptin add-on therapy to insulin on blood glycemic fluctuations in patients with type 2 diabetes

PubMed Central

Li, Feng-fei; Jiang, Lan-lan; Yan, Reng-na; Zhu, Hong-hong; Zhou, Pei-hua; Zhang, Dan-feng; Su, Xiao-fei; Wu, Jin-dan; Ye, Lei; Ma, Jian-hua

2016-01-01

Abstract Background: To investigate whether saxagliptin add-on therapy to continuous subcutaneous insulin infusion (CSII) further improve blood glycemic control than CSII therapy in patients with newly diagnosed type 2 diabetes (T2D). Methods: This was a single-center, randomized, control, open-labeled trial. Newly diagnosed T2D patients were recruited between February 2014 and December 2015. Subjects were divided into saxagliptin add-on therapy to CSII group (n = 31) and CSII therapy group (n = 38). The treatment was maintained for 4 weeks. Oral glucose tolerance test was performed at baseline. Serum samples were obtained before and 30 and 120 minutes after oral administration for glucose, insulin, and C-peptide determination. Continuous glucose monitoring (CGM) was performed before and endpoint. Results: A total of 69 subjects were admitted. After 4-week therapy, CGM data showed that patients with saxagliptin add-on therapy exhibited further improvement of mean amplitude glycemic excursion (MAGE), the incremental area under curve of plasma glucose >7.8 and 10 mmol/L compared with that of control group. In addition, the hourly mean blood glucose concentrations, especially between 0000 and 0600 in patient with saxagliptin add-on therapy, were significantly lower compared with that of the control patients. Furthermore, patients in saxagliptin add-on group needed lower insulin dose to maintain euglycemic control. In addition, severe hypoglycemic episode was not observed from any group. Conclusion: Saxagliptin add-on therapy to insulin had the ability of further improve blood glycemic controlling, with lower insulin dose required by patients with T2D to maintain euglycemic controlling. PMID:27787387

Effects of saxagliptin add-on therapy to insulin on blood glycemic fluctuations in patients with type 2 diabetes: A randomized, control, open-labeled trial.

PubMed

Li, Feng-Fei; Jiang, Lan-Lan; Yan, Reng-Na; Zhu, Hong-Hong; Zhou, Pei-Hua; Zhang, Dan-Feng; Su, Xiao-Fei; Wu, Jin-Dan; Ye, Lei; Ma, Jian-Hua

2016-10-01

To investigate whether saxagliptin add-on therapy to continuous subcutaneous insulin infusion (CSII) further improve blood glycemic control than CSII therapy in patients with newly diagnosed type 2 diabetes (T2D). This was a single-center, randomized, control, open-labeled trial. Newly diagnosed T2D patients were recruited between February 2014 and December 2015. Subjects were divided into saxagliptin add-on therapy to CSII group (n = 31) and CSII therapy group (n = 38). The treatment was maintained for 4 weeks. Oral glucose tolerance test was performed at baseline. Serum samples were obtained before and 30 and 120 minutes after oral administration for glucose, insulin, and C-peptide determination. Continuous glucose monitoring (CGM) was performed before and endpoint. A total of 69 subjects were admitted. After 4-week therapy, CGM data showed that patients with saxagliptin add-on therapy exhibited further improvement of mean amplitude glycemic excursion (MAGE), the incremental area under curve of plasma glucose >7.8 and 10 mmol/L compared with that of control group. In addition, the hourly mean blood glucose concentrations, especially between 0000 and 0600 in patient with saxagliptin add-on therapy, were significantly lower compared with that of the control patients. Furthermore, patients in saxagliptin add-on group needed lower insulin dose to maintain euglycemic control. In addition, severe hypoglycemic episode was not observed from any group. Saxagliptin add-on therapy to insulin had the ability of further improve blood glycemic controlling, with lower insulin dose required by patients with T2D to maintain euglycemic controlling.

One-year effectiveness of two hypocaloric diets with different protein/carbohydrate ratios in weight loss and insulin resistance.

PubMed

Calleja Fernández, A; Vidal Casariego, A; Cano Rodríguez, I; Ballesteros Pomar, Ma D

2012-01-01

The maintenance of weight loss may be influenced by the distribution of macronutrients in the diet and insulin sensitivity. The objective of the study was to evaluate the longterm effect of two hypocaloric diets with different protein/carbohydrate ratios in overweight and obese individuals either with insulin resistance (IR) or without insulin resistance (IS). Prospective, randomized, clinical intervention study. Forty patients were classified as IR/IS after a 75 g oral glucose tolerance test and then randomized to a diet with either 40% carbohydrate/30% protein/30% fat (diet A) or 55% carbohydrate/15% protein/30% fat (diet B). After one year of follow-up there was no difference in weight loss between diets A and B in each group, but the IS group maintained weight loss better than the IR group [-5.7 (3.9) vs. -0.6 (4.1); P = 0.04]. No differences were found in either Homeostasis Model Assessment (HOMA) or other metabolic glucose parameters except lower insulin at 120 minutes with diet A [21.40 (8.30) vs. 71.40 (17.11); P = 0.02]. The hypocaloric diets with different protein/carbohydrate ratios produced similar changes in weight. Insulin resistance may play a negative role in maintaining weight loss.

Effect of a mitochondrial-targeted coenzyme Q analog on pancreatic β-cell function and energetics in high fat fed obese mice.

PubMed

Imai, Yumi; Fink, Brian D; Promes, Joseph A; Kulkarni, Chaitanya A; Kerns, Robert J; Sivitz, William I

2018-06-01

We recently reported that mitoquinone (mitoQ, 500 μmol/L) added to drinking water of C57BL/6J mice attenuated weight gain and reduced oxidative stress when administered to high-fat (HF) fed mice. Here, we examined the effects of mitoQ administered to HF fed mice on pancreatic islet morphology, dynamics of insulin secretion, and islet mitochondrial metabolism. C57BL/6J mice were fed HF for 130 days while we administered vehicle (cyclodextrin [CD]) or mitoQ added to the drinking water at up to 500 μmol/L. MitoQ-treated mice vs vehicle gained significantly less weight, expended significantly more energy as determined by indirect calorimetry, and trended to consume less (nonsignificant) food. As we and others reported before, mitoQ-treated mice drank less water but showed no difference in percent body fluid by nuclear magnetic resonance. Circulating insulin and glucose-stimulated insulin secretion by isolated islets were decreased in mitoQ-treated mice while insulin sensitivity (plasma insulin x glucose) was greater. Islet respiration as basal oxygen consumption (OCR), OCR directed at ATP synthesis, and maximal uncoupled OCR were also reduced in mitoQ-treated mice. Quantitative morphologic studies revealed that islet size was reduced in the mitoQ-treated mice while visual inspection of histochemically stained sections suggested that mitoQ reduced islet lipid peroxides. MitoQ markedly improved liver function as determined by plasma alanine aminotransferase. In summary, mitoQ treatment reduced the demand for insulin and reduced islet size, likely consequent to the action of mitoQ to mitigate weight gain and improve liver function. This article has been contributed to by US Government employees and their work is in the public domain in the USA.

Alternate-day fasting diet improves fructose-induced insulin resistance in mice.

PubMed

Beigy, M; Vakili, S; Berijani, S; Aminizade, M; Ahmadi-Dastgerdi, M; Meshkani, R

2013-12-01

Increased fructose consumption is linked to insulin resistance, weight gain, hyperlipidemia and hypertension. Although the advantages of several dietary restriction regimens have been demonstrated, the effects of alternate-day fasting (ADF) on fructose-induced insulin resistance have not yet been studied. This study is based on a new modification on ADF by combining the fructose-rich solution (10% w/v) and regular mice diet. Mice were randomly allocated into four groups: ADF50% (50% restriction in chow food intake but ad libitum fructose drink), ADF100% (100% restriction for chow food but ad libitum fructose drink), control (ad libitum chow food intake plus tap water) and daily food and fructose (DFF) (had free access to both chow and fructose solution). Biweekly fasting blood sugar (FBS), glucose tolerance test (GTT) and insulin tolerance test (ITT) were conducted. All groups gained weight during the study (p < 0.05). Body weights of DFF and control groups did not differ from that of ADF groups, but ADF50% gained more (p < 0.01) weights than ADF100% through the study. Total calorie intake (feed + fast days) of ADF50% was higher than that of ADF100% (p < 0.001) and control (p < 0.03). In addition, ADF groups consumed more energy than the control and DFF groups in feed (ad libitum) days (p < 0.05). At the end of the study, the mean FBS levels in the control and ADF100% groups were similar and significantly lower in relation to that of DFF and ADF50% groups (p < 0.01). Measurements of area under the curve in GTT and ITT revealed that the ADF100% group was more insulin-sensitive than the DFF and ADF50% groups. In conclusion, these data suggest that the ADF100% improves fructose-induced insulin resistance in mice. © 2013 Blackwell Verlag GmbH.

When Intensive Insulin Therapy (MDI) Fails in Patients With Type 2 Diabetes: Switching to GLP-1 Receptor Agonist Versus Insulin Pump.

PubMed

Cohen, Ohad; Filetti, Sebastiano; Castañeda, Javier; Maranghi, Marianna; Glandt, Mariela

2016-08-01

Treatment with insulin, alone or with oral or injectable hypoglycemic agents, is becoming increasingly common in patients with type 2 diabetes. However, approximately 40% of patients fail to reach their glycemic targets with the initially prescribed regimen and require intensification of insulin therapy, which increases the risks of weight gain and hypoglycemia. Many of these patients eventually reach a state in which further increases in the insulin dosage fail to improve glycemic control while increasing the risks of weight gain and hypoglycemia. The recently completed OpT2mise clinical trial showed that continuous subcutaneous insulin infusion (CSII) is more effective in reducing glycated hemoglobin (HbA1c) than intensification of multiple daily injection (MDI) insulin therapy in patients with type 2 diabetes who do not respond to intensive insulin therapy. CSII therapy may also be useful in patients who do not reach glycemic targets despite multidrug therapy with basal-bolus insulin and other agents, including glucagon-like peptide (GLP)-1 receptor agonists; current guidelines offer no recommendations for the treatment of such patients. Importantly, insulin and GLP-1 receptor agonists have complementary effects on glycemia and, hence, can be used either sequentially or in combination in the initial management of diabetes. Patients who have not previously failed GLP-1 receptor agonist therapy may show reduction in weight and insulin dose, in addition to moderate improvement in HbA1c, when GLP-1 receptor agonist therapy is added to MDI regimens. In subjects with long-standing type 2 diabetes who do not respond to intensive insulin therapies, switching from MDI to CSII and/or the addition of GLP-1 receptor agonists to MDI have the potential to improve glycemic control without increasing the risk of adverse events. © 2016 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

Chardonnay Grape Seed Flour Ameliorates Hepatic Steatosis and Insulin Resistance via Altered Hepatic Gene Expression for Oxidative Stress, Inflammation, and Lipid and Ceramide Synthesis in Diet-Induced Obese Mice

PubMed Central

Seo, Kun-Ho; Bartley, Glenn E.; Tam, Christina; Kim, Hong-Seok; Kim, Dong-Hyeon; Chon, Jung-Whan; Yokoyama, Wallace

2016-01-01

To identify differentially expressed hepatic genes contributing to the improvement of high-fat (HF) diet-induced hepatic steatosis and insulin resistance following supplementation of partially defatted flavonoid-rich Chardonnay grape seed flour (ChrSd), diet-induced obese (DIO) mice were fed HF diets containing either ChrSd or microcrystalline cellulose (MCC, control) for 5 weeks. The 2-h insulin area under the curve was significantly lowered by ChrSd, indicating that ChrSd improved insulin sensitivity. ChrSd intake also significantly reduced body weight gain, liver and adipose tissue weight, hepatic lipid content, and plasma low-density lipoprotein (LDL)-cholesterol, despite a significant increase in food intake. Exon microarray analysis of hepatic gene expression revealed down-regulation of genes related to triglyceride and ceramide synthesis, immune response, oxidative stress, and inflammation and upregulation of genes related to fatty acid oxidation, cholesterol, and bile acid synthesis. In conclusion, the effects of ChrSd supplementation in a HF diet on weight gain, insulin resistance, and progression of hepatic steatosis in DIO mice were associated with modulation of hepatic genes related to oxidative stress, inflammation, ceramide synthesis, and lipid and cholesterol metabolism. PMID:27977712

Polycystic ovary syndrome: insight into pathogenesis and a common association with insulin resistance.

PubMed

Barber, Thomas M; Dimitriadis, George K; Andreou, Avgi; Franks, Stephen

2016-06-01

Polycystic ovary syndrome (PCOS) is a common condition that typically develops in reproductive-age women. The cardinal clinical and biochemical characteristics of PCOS include reproductive dysfunction and hyperandrogenic features. PCOS is also strongly associated with obesity based on data from epidemiological and genetic studies. Accordingly, PCOS often becomes manifest in those women who carry a genetic predisposition to its development, and who also gain weight. The role of weight gain and obesity in the development of PCOS is mediated at least in part, through worsening of insulin resistance. Compensatory hyperinsulinaemia that develops in this context disrupts ovarian function, with enhanced androgen production and arrest of ovarian follicular development. Insulin resistance also contributes to the strong association of PCOS with adverse metabolic risk, including dysglycaemia, dyslipidaemia and fatty liver. Conversely, modest weight loss of just 5% body weight with improvement in insulin sensitivity, frequently results in clinically meaningful improvements in hyperandrogenic, reproductive and metabolic features. Future developments of novel therapies for obese women with PCOS should focus on promotion of weight loss and improvement in insulin sensitivity. In this context, therapies that complement lifestyle changes such as dietary modification and exercise, particularly during the maintenance phase of weight loss are important. Putative novel targets for therapy in PCOS include human brown adipose tissue. © 2016 Royal College of Physicians.

Induction of steatohepatitis (NASH) with insulin resistance in wildtype B6 mice by a western-type diet containing soybean oil and cholesterol.

PubMed

Henkel, Janin; Coleman, Charles Dominic; Schraplau, Anne; Jӧhrens, Korinna; Weber, Daniela; Castro, José Pedro; Hugo, Martin; Schulz, Tim Julius; Krämer, Stephanie; Schürmann, Annette; Püschel, Gerhard Paul

2017-03-21

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are hepatic manifestations of the metabolic syndrome. Many currently used animal models of NAFLD/NASH lack clinical features of either NASH or metabolic syndrome such as hepatic inflammation and fibrosis (e.g. high-fat diets) or overweight and insulin resistance (e.g. methionine-choline-deficient diets) or they are based on monogenetic defects (e.g. ob/ob mice). In the current study, a western-type diet containing soybean oil with high n 6-PUFA and 0.75% cholesterol (SOD+Cho) induced steatosis, inflammation and fibrosis accompanied by hepatic lipid peroxidation and oxidative stress in livers of C57BL/6-mice which in addition showed increased weight gain and insulin resistance, thus displaying a phenotype closely resembling all clinical features of NASH in patients with metabolic syndrome. In striking contrast a soybean oil-containing western-type diet without cholesterol (SOD) induced only mild steatosis but neither hepatic inflammation nor fibrosis, weight gain or insulin resistance. Another high-fat diet mainly consisting of lard and supplemented with fructose in drinking water (LAD+Fru) resulted in more prominent weight gain, insulin resistance and hepatic steatosis than SOD+Cho but livers were devoid of inflammation and fibrosis. Although both LAD+Fru- and SOD+Cho-fed animals had high plasma cholesterol, liver cholesterol was elevated only in SOD+Cho animals. Cholesterol induced expression of chemotactic and inflammatory cytokines in cultured Kupffer cells and rendered hepatocytes more susceptible to apoptosis. Summarizing, dietary cholesterol in SOD+Cho diet may trigger hepatic inflammation and fibrosis. SOD+Cho-fed animals may be a useful disease model displaying many clinical features of patients with the metabolic syndrome and NASH.

The effect of diet composition on weight gain and pyruvate dehydrogenase activity in heart muscle in the gold thioglucose obese mouse.

PubMed

Steinbeck, K; Caterson, I D; Astbury, L; Turtle, J R

1987-01-01

Pyruvate dehydrogenase complex activity is the major determinant of glucose oxidation in animal cells. Tissue glucose oxidation is reduced in obesity and states of insulin resistance and alternate fuels are utilized for energy and pyruvate dehydrogenase activity is reduced in cardiac muscle in obesity. The effect of four different diets (standard laboratory chow, high-carbohydrate, high-protein and high-fat) on weight gain, cardiac pyruvate dehydrogenase activity (PDHa) and serum insulin, glucose and free fatty acids was studied in the gold thioglucose obese mouse. All four diets produced significant weight gain in the gold thioglucose injected animal. Cardiac PDHa was influenced by both obesity and diet composition. The obese chow-fed animals had significantly reduced PDHa. On high-carbohydrate and high-protein feeding lean controls had a significant decrease in cardiac PDHa compared to chow-fed controls, but only in high-carbohydrate-fed animals was this further reduced by obesity. High-fat feeding produced a rapid and almost complete suppression of PDHa in both lean and obese animals. Serum insulin, glucose and free fatty acids were also affected by diet as well as obesity. The highest serum insulins were found in chow-fed obese animals whereas the highest serum glucoses were in high-carbohydrate-fed obese animals. Hyperinsulinaemia did not develop in the high-fat-fed obese animal, but the highest serum free fatty acids were found in high-fat feeding. It is concluded that both diet composition and obesity affect cardiac PDHa and therefore glucose utilization in this tissue. Insulin resistance in the acute stages of obesity development is also affected by diet composition.

Reduced insulin signaling maintains electrical transmission in a neural circuit in aging flies

PubMed Central

McGourty, Kieran; Allen, Marcus J.; Madem, Sirisha Kudumala; Adcott, Jennifer; Kerr, Fiona; Wong, Chi Tung; Vincent, Alec; Godenschwege, Tanja; Boucrot, Emmanuel; Partridge, Linda

2017-01-01

Lowered insulin/insulin-like growth factor (IGF) signaling (IIS) can extend healthy lifespan in worms, flies, and mice, but it can also have adverse effects (the “insulin paradox”). Chronic, moderately lowered IIS rescues age-related decline in neurotransmission through the Drosophila giant fiber system (GFS), a simple escape response neuronal circuit, by increasing targeting of the gap junctional protein innexin shaking-B to gap junctions (GJs). Endosomal recycling of GJs was also stimulated in cultured human cells when IIS was reduced. Furthermore, increasing the activity of the recycling small guanosine triphosphatases (GTPases) Rab4 or Rab11 was sufficient to maintain GJs upon elevated IIS in cultured human cells and in flies, and to rescue age-related loss of GJs and of GFS function. Lowered IIS thus elevates endosomal recycling of GJs in neurons and other cell types, pointing to a cellular mechanism for therapeutic intervention into aging-related neuronal disorders. PMID:28902870

Preteen insulin levels interact with caloric intake to predict increases in obesity at ages 18 to 19 years: a 10-year prospective study of black and white girls.

PubMed

Morrison, John A; Glueck, Charles J; Wang, Ping

2010-05-01

We evaluated the associations of teenage insulin and adolescent diet with 10-year weight gain in an analysis sample of black and white girls matched for pubertal stage, body mass index (BMI) (or fat mass), and insulin at ages 9 to 10 years. We hypothesized that preteen insulin and insulin resistance would interact with dietary factors to positively predict increases in BMI. Furthermore, we hypothesized that increased insulin and insulin resistance, interacting with higher caloric intake during adolescence, would lead to greater increments in BMI in black girls than in white girls. Prospective 10-year follow-up was performed on 215 pairs of black and white schoolgirls matched at baseline by BMI (or fat mass), insulin, and pubertal stage, with repeated measures of body habitus, insulin, and dietary intake. When matched for BMI, black girls had higher fat-free mass and white girls had higher fat mass at ages 9 to 10 years. Black-white differences in caloric intake were not significant at ages 9 to 10 years, but black girls consumed more calories at age 19 years. Black girls consumed a greater percentage of calories from fat throughout. At age 19 years, black girls had higher BMI, fat mass index, and insulin. When matched at ages 9 to 10 years for fat mass, black girls were heavier, had higher BMI, and had greater fat-free mass. By ages 18 to 19 years, black girls continued to have higher BMI, but had accrued higher fat mass and a higher percentage of body fat. By stepwise multiple regression, 10-year increases in BMI were predicted by ages 9 to 10 years BMI, 10-year change in insulin, and a 3-way interaction between ages 9 to 10 years insulin, adolescent caloric intake, and race (higher in black girls) (all Ps < .0001). Insulin at ages 9 to 10 years interacts with caloric intake to increase BMI by age 19 years. There appear to be intrinsic black-white metabolic differences that lead to greater gains in fat during adolescence in black girls. Evaluating BMI and insulin at ages 9 to 10 years could identify girls (particularly black) who would optimally benefit from dietary and exercise interventions to avoid obesity.

Central insulin and leptin-mediated autonomic control of glucose homeostasis

PubMed Central

Marino, Joseph S.; Xu, Yong; Hill, Jennifer W.

2016-01-01

Largely as a result of rising obesity rates, the incidence of type 2 diabetes is escalating rapidly. Type 2 diabetes results from multi-organ dysfunctional glucose metabolism. Recent publications have highlighted hypothalamic insulin- and adipokine-sensing as a major determinant of peripheral glucose and insulin responsiveness. The preponderance of evidence indicates that the brain is the master regulator of glucose homeostasis, and that hypothalamic insulin and leptin signaling in particular play a crucial role in the development of insulin resistance. This review discusses the neuronal crosstalk between the hypothalamus, autonomic nervous system, and tissues associated with the pathogenesis of type 2 diabetes, and how hypothalamic insulin and leptin signaling are integral to maintaining normal glucose homeostasis. PMID:21489811

Central insulin and leptin-mediated autonomic control of glucose homeostasis.

PubMed

Marino, Joseph S; Xu, Yong; Hill, Jennifer W

2011-07-01

Largely as a result of rising obesity rates, the incidence of type 2 diabetes is escalating rapidly. Type 2 diabetes results from multi-organ dysfunctional glucose metabolism. Recent publications have highlighted hypothalamic insulin- and adipokine-sensing as a major determinant of peripheral glucose and insulin responsiveness. The preponderance of evidence indicates that the brain is the master regulator of glucose homeostasis, and that hypothalamic insulin and leptin signaling in particular play a crucial role in the development of insulin resistance. This review discusses the neuronal crosstalk between the hypothalamus, autonomic nervous system, and tissues associated with the pathogenesis of type 2 diabetes, and how hypothalamic insulin and leptin signaling are integral to maintaining normal glucose homeostasis. Copyright © 2011 Elsevier Ltd. All rights reserved.

Spargel/dPGC-1 Is a New Downstream Effector in the Insulin–TOR Signaling Pathway in Drosophila

PubMed Central

Mukherjee, Subhas; Duttaroy, Atanu

2013-01-01

Insulin and target of rapamycin (TOR) signaling pathways converge to maintain growth so a proportionate body form is attained. Insufficiency in either insulin or TOR results in developmental growth defects due to low ATP level. Spargel is the Drosophila homolog of PGC-1, which is an omnipotent transcriptional coactivator in mammals. Like its mammalian counterpart, Spargel/dPGC-1 is recognized for its role in energy metabolism through mitochondrial biogenesis. An earlier study demonstrated that Spargel/dPGC-1 is involved in the insulin–TOR signaling, but a comprehensive analysis is needed to understand exactly which step of this pathway Spargel/PGC-1 is essential. Using genetic epistasis analysis, we demonstrated that a Spargel gain of function can overcome the TOR and S6K mediated cell size and cell growth defects in a cell autonomous manner. Moreover, the tissue-restricted phenotypes of TOR and S6k mutants are rescued by Spargel overexpression. We have further elucidated that Spargel gain of function sets back the mitochondrial numbers in growth-limited TOR mutant cell clones, which suggests a possible mechanism for Spargel action on cells and tissue to attain normal size. Finally, excess Spargel can ameliorate the negative effect of FoxO overexpression only to a limited extent, which suggests that Spargel does not share all of the FoxO functions and consequently cannot significantly rescue the FoxO phenotypes. Together, our observation established that Spargel/dPGC-1 is indeed a terminal effector in the insulin–TOR pathway operating below TOR, S6K, Tsc, and FoxO. This led us to conclude that Spargel should be incorporated as a new member of this growth-signaling pathway. PMID:23934892

Dietary Anthocyanins and Insulin Resistance: When Food Becomes a Medicine.

PubMed

Belwal, Tarun; Nabavi, Seyed Fazel; Nabavi, Seyed Mohammad; Habtemariam, Solomon

2017-10-12

Insulin resistance is an abnormal physiological state that occurs when insulin from pancreatic β-cells is unable to trigger a signal transduction pathway in target organs such as the liver, muscles and adipose tissues. The loss of insulin sensitivity is generally associated with persistent hyperglycemia (diabetes), hyperinsulinemia, fatty acids and/or lipid dysregulation which are often prevalent under obesity conditions. Hence, insulin sensitizers are one class of drugs currently employed to treat diabetes and associated metabolic disorders. A number of natural products that act through multiple mechanisms have also been identified to enhance insulin sensitivity in target organs. One group of such compounds that gained interest in recent years are the dietary anthocyanins. Data from their in vitro, in vivo and clinical studies are scrutinized in this communication to show their potential health benefit through ameliorating insulin resistance. Specific mechanism of action ranging from targeting specific signal transduction receptors/enzymes to the general antioxidant and anti-inflammatory mechanisms of insulin resistance are presented.

A Novel Membrane-Based Anti-Diabetic Action of Atorvastatin

PubMed Central

Horvath, Emily M.; Tackett, Lixuan; Elmendorf, Jeffrey S.

2008-01-01

We recently found that chromium picolinate (CrPic), a nutritional supplement thought to improve insulin sensitivity in individuals with impaired glucose tolerance, enhances insulin action by lowering plasma membrane (PM) cholesterol. Recent in vivo studies suggest that cholesterol-lowering statin drugs benefit insulin sensitivity in insulin-resistant patients, yet a mechanism is unknown. We report here that atorvastatin (ATV) diminished PM cholesterol by 22% (P<0.05) in 3T3-L1 adipocytes. As documented for CrPic, this small reduction in PM cholesterol enhanced insulin action. Replenishment of cholesterol mitigated the positive effects of ATV on insulin sensitivity. Co-treatment with CrPic and ATV did not amplify the extent of PM cholesterol loss or insulin sensitivity gain. In addition, analyses of insulin signal transduction suggest a non-signaling basis of both therapies. Our data reveal an unappreciated beneficial non-hepatic effect of statin action and highlight a novel mechanistic similarity between two recently recognized therapies of impaired glucose tolerance. PMID:18514061

Insulin and insulin-like growth factor-1 induce pronounced hypertrophy of skeletal myofibers in tissue culture

NASA Technical Reports Server (NTRS)

Vandenburgh, Herman H.; Karlisch, Patricia; Shansky, Janet

1990-01-01

Skeletal myofibers differentiated from primary avian myoblasts in tissue culture can be maintained in positive nitrogen balance in a serum-free medium for at least 6 to 7 days when embedded in a three dimensional collagen gel matrix. The myofibers are metabolically sensitive to physiological concentrations of insulin but these concentrations do not stimulate cell growth. Higher insulin concentrations stimulate both cell hyperplasia and myofiber hypertrophy. Cell growth results from a long term 42 percent increase in total protein synthesis and a 38 percent increase in protein degradation. Myofiber diameters increase by 71 to 98 percent after 6 to 7 days in insulin-containing medium. Insulin-like growth factor-1 but not insulin-like growth factor-2, at 250 ng/ml, is as effective as insulin in stimulating cell hyperplasia and myofiber hypertrophy. This model system provides a new method for studying the long-term anabolic effects of insulin and insulin-like growth factors on myofiber hypertrophy under defined tissue culture conditions.

Intensive insulin therapy improves insulin sensitivity and mitochondrial function in severely burned children.

PubMed

Fram, Ricki Y; Cree, Melanie G; Wolfe, Robert R; Mlcak, Ronald P; Qian, Ting; Chinkes, David L; Herndon, David N

2010-06-01

To institute intensive insulin therapy protocol in an acute pediatric burn unit and study the mechanisms underlying its benefits. Prospective, randomized study. An acute pediatric burn unit in a tertiary teaching hospital. Children, 4-18 yrs old, with total body surface area burned > or =40% and who arrived within 1 wk after injury were enrolled in the study. Patients were randomized to one of two groups. Intensive insulin therapy maintained blood glucose levels between 80 and 110 mg/dL. Conventional insulin therapy maintained blood glucose < or =215 mg/dL. Twenty patients were included in the data analysis consisting of resting energy expenditure, whole body and liver insulin sensitivity, and skeletal muscle mitochondrial function. Studies were performed at 7 days postburn (pretreatment) and at 21 days postburn (posttreatment). Resting energy expenditure significantly increased posttreatment (1476 +/- 124 to 1925 +/- 291 kcal/m(2) x day; p = .02) in conventional insulin therapy as compared with a decline in intensive insulin therapy. Glucose infusion rate was identical between groups before treatment (6.0 +/- 0.8 conventional insulin therapy vs. 6.8 +/- 0.9 mg/kg x min intensive insulin therapy; p = .5). Intensive insulin therapy displayed a significantly higher glucose clamp infusion rate posttreatment (9.1 +/- 1.3 intensive insulin therapy versus 4.8 +/- 0.6 mg/kg x min conventional insulin therapy, p = .005). Suppression of hepatic glucose release was significantly greater in the intensive insulin therapy after treatment compared with conventional insulin therapy (5.0 +/- 0.9 vs. 2.5 +/- 0.6 mg/kg x min; intensive insulin therapy vs. conventional insulin therapy; p = .03). States 3 and 4 mitochondrial oxidation of palmitate significantly improved in intensive insulin therapy (0.9 +/- 0.1 to 1.7 +/- 0.1 microm O(2)/CS/mg protein/min for state 3, p = .004; and 0.7 +/- 0.1 to 1.3 +/- 0.1 microm O(2)/CS/mg protein/min for state 4, p < .002), whereas conventional insulin therapy remained at the same level of activity (0.9 +/- 0.1 to 0.8 +/- 0.1 microm O(2)/CS/mg protein/min for state 3, p = .4; 0.6 +/- 0.03 to 0.7 +/- 0.1 microm O(2)/CS/mg protein/min, p = .6). Controlling blood glucose levels < or =120 mg/dL using an intensive insulin therapy protocol improves insulin sensitivity and mitochondrial oxidative capacity while decreasing resting energy expenditure in severely burned children.

Effects of Bisphenol A on glucose homeostasis and brain insulin signaling pathways in male mice.

PubMed

Fang, Fangfang; Chen, Donglong; Yu, Pan; Qian, Wenyi; Zhou, Jing; Liu, Jingli; Gao, Rong; Wang, Jun; Xiao, Hang

2015-02-01

The potential effects of Bisphenol A (BPA) on peripheral insulin resistance have recently gained more attention, however, its functions on brain insulin resistance are still unknown. The aim of the present study was to investigate the effects of BPA on insulin signaling and glucose transport in mouse brain. The male mice were administrated of 100 μg/kg/day BPA or vehicle for 15 days then challenged with glucose and insulin tolerance tests. The insulin levels were detected with radioimmunoassay (RIA), and the insulin signaling pathways were investigated by Western blot. Our results revealed that BPA significantly increased peripheral plasma insulin levels, and decreased the insulin signals including phosphorylated insulin receptor (p-IR), phosphorylated insulin receptor substrate 1 (p-IRS1), phosphorylated protein kinase B (p-AKT), phosphorylated glycogen synthase kinase 3β (p-GSK3β) and phosphorylated extracellular regulated protein kinases (p-ERK1/2) in the brain, though insulin expression in both hippocampus and profrontal cortex was increased. In parallel, BPA exposure might contribute to glucose transport disturbance in the brain since the expression of glucose transporters were markedly decreased. In conclusion, BPA exposure perturbs the insulin signaling and glucose transport in the brain, therefore, it might be a risk factor for brain insulin resistance. Copyright © 2015 Elsevier Inc. All rights reserved.

Unpredictable Feeding Impairs Glucose Tolerance in Growing Lambs

PubMed Central

Jaquiery, Anne L.; Oliver, Mark H.; Landon-Lane, Nina; Matthews, Samuel J.; Harding, Jane E.; Bloomfield, Frank H.

2013-01-01

Irregular eating is associated with insulin resistance and metabolic disease in adults but may affect young, growing children differently. We investigated the metabolic effects of unpredictable feeding in female juvenile lambs randomly assigned to receive, for six weeks, maintenance feed given twice daily in equal portions (Control Group, C; n = 24) or the same weekly feed amount in aliquots of variable size at unpredictable times (Unpredictable Group, U; n = 21). Intravenous glucose tolerance tests (IVGTT), insulin tolerance tests (ITT), and measurement of diurnal plasma cortisol concentrations were performed pre and post the dietary intervention. Groups were compared using t test and RM ANOVA. Weight gain was similar in both groups (C 18±2%; U 16±2% of initial body weight). Glucose area under the curve (AUC) was unchanged in C (AUC pre 818±34, post 801±33 mmol.min.l−1), but increased by 20% in U (pre 830±25, post 1010±19 mmol.min.l−1; p<0.0001), with an inadequate insulin response to glucose load (log(AUC insulin first 40 minutes) post intervention C 1.49±0.04 vs U 1.36±0.04 ng.min.ml−1; p = 0.03). Insulin tolerance and diurnal variation of plasma cortisol concentrations were not different between groups. Unpredictable feeding impairs insulin response to glucose in growing lambs despite high quality food and normal weight gain. Irregular eating warrants investigation as a potentially remediable risk factor for disordered glucose metabolism. PMID:23613779

Ultra-structural study of insulin granules in pancreatic β-cells of db/db mouse by scanning transmission electron microscopy tomography.

PubMed

Xue, Yanhong; Zhao, Wei; Du, Wen; Zhang, Xiang; Ji, Gang; Ying, Wang; Xu, Tao

2012-07-01

Insulin granule trafficking is a key step in the secretion of glucose-stimulated insulin from pancreatic β-cells. The main feature of type 2 diabetes (T2D) is the failure of pancreatic β-cells to secrete sufficient amounts of insulin to maintain normal blood glucose levels. In this work, we developed and applied tomography based on scanning transmission electron microscopy (STEM) to image intact insulin granules in the β-cells of mouse pancreatic islets. Using three-dimensional (3D) reconstruction, we found decreases in both the number and the grey level of insulin granules in db/db mouse pancreatic β-cells. Moreover, insulin granules were closer to the plasma membrane in diabetic β-cells than in control cells. Thus, 3D ultra-structural tomography may provide new insights into the pathology of insulin secretion in T2D.

Microencapsulation techniques to develop formulations of insulin for oral delivery: a review.

PubMed

Cárdenas-Bailón, Fernando; Osorio-Revilla, Guillermo; Gallardo-Velázquez, Tzayhrí

2013-01-01

Oral insulin delivery represents one of the most challenging goals for pharmaceutical industry. In general, it is accepted that oral administration of insulin would be more accepted by patients and insulin would be delivered in a more physiological way than the parenteral route. From all strategies to deliverer insulin orally, microencapsulation or nanoencapsulation of insulin are the most promising approaches because these techniques protect insulin from enzymatic degradation in stomach, show a good release profile at intestine pH values, maintain biological activity during formulation and enhance intestinal permeation at certain extent. From different microencapsulation techniques, it seems that complex coacervation, multiple emulsion and internal gelation are the most appropriate techniques to encapsulate insulin due to their relative ease of preparation. Besides that, the use of organic solvents is not required and can be scaled up at low cost; however, relative oral bioavailability still needs to be improved.

Overnutrition in spiny mice (Acomys cahirinus): beta-cell expansion leading to rupture and overt diabetes on fat-rich diet and protective energy-wasting elevation in thyroid hormone on sucrose-rich diet.

PubMed

Shafrir, E

2000-01-01

The investigation of diabetes propensity in spiny mice, performed in Geneva and Jerusalem colonies, is reviewed. Spiny mice live in semi-desert regions of the eastern Mediterranean countries. Those transferred to Geneva in the 1950s were maintained on a rodent diet supplemented by fat-rich seeds. They became obese, exhibited pancreatic islet hyperplasia and hypertrophy. Low insulin secretion response was characteristic of this species, despite ample pancreatic content of insulin. After a few months, diabetes with ketosis occurred, often suddenly, in association with islet cell disintegration. In Jerusalem the spiny mice were collected from their native habitat and placed on diets containing 50% sucrose or fat-rich seed diets. On a sucrose-rich diet, spiny mice developed hepatomegaly, lipogenic enzyme hyperactivity, and elevation in very low density lipoproteins as a result of metabolism of the fructose component mainly in the liver. No overt diabetes or pancreatic islet disintegration were observed, although insulin content and beta-cell hypertrophy and hyperplasia were apparent. On a fat-rich diet, spiny mice exhibited marked weight gain, adipose tissue growth and low hepatic lipogenesis. The obesity was accompanied by mild hyperglycemia and hyperinsulinemia with glucose intolerance leading to an occasional glucosuria after several months on the diet. The sucrose diet induced an extrathyroidal elevation of triiodothyronine (T(3)). Serum T(3) level and hepatic T(4)-T(3) conversion were increased, while serum T(4) levels tended to decrease. The activity of the T(3)-inducible hepatic mitochondrial FAD-glycerophosphate oxidase and K(+)/Na(+)-ATPase, as well as body temperature were increased, indicating that the sucrose diet was associated with enhanced thermogenesis and energy-wasting metabolic cycling. The sucrose-rich diet might exert an adaptive thermogenesis-mediated defense mechanism, protecting against excessive weight gain and disruptive pancreatic islet lesion. After 18 months maintenance on sucrose-rich versus fat-rich diets the number of animals surviving was significantly higher on the sucrose diet whereas on the fat diet a significant number of animals succumbed to expansive islet cell disruption and diabetes.

MiRNAs in β-Cell Development, Identity, and Disease

PubMed Central

Martinez-Sanchez, Aida; Rutter, Guy A.; Latreille, Mathieu

2017-01-01

Pancreatic β-cells regulate glucose metabolism by secreting insulin, which in turn stimulates the utilization or storage of the sugar by peripheral tissues. Insulin insufficiency and a prolonged period of insulin resistance are usually the core components of type 2 diabetes (T2D). Although, decreased insulin levels in T2D have long been attributed to a decrease in β-cell function and/or mass, this model has recently been refined with the recognition that a loss of β-cell “identity” and dedifferentiation also contribute to the decline in insulin production. MicroRNAs (miRNAs) are key regulatory molecules that display tissue-specific expression patterns and maintain the differentiated state of somatic cells. During the past few years, great strides have been made in understanding how miRNA circuits impact β-cell identity. Here, we review current knowledge on the role of miRNAs in regulating the acquisition of the β-cell fate during development and in maintaining mature β-cell identity and function during stress situations such as obesity, pregnancy, aging, or diabetes. We also discuss how miRNA function could be harnessed to improve our ability to generate β-cells for replacement therapy for T2D. PMID:28123396

Insulin and Weight Gain: Keep the Pounds Off

MedlinePlus

... liraglutide (Victoza), albiglutide (Tarzeum), dulaglutide (Trulicity), sitagliptin (Januvia), saxagliptin (Onglyza), canagliflozin (Invokana), dapagliflozin (Farxiga), empagliflozin (Jardiance) and ...

Genetic markers of insulin sensitivity and insulin secretion are associated with spontaneous postnatal growth and response to growth hormone treatment in short SGA children: the North European SGA Study (NESGAS).

PubMed

Jensen, Rikke Beck; Thankamony, Ajay; Day, Felix; Scott, Robert A; Langenberg, Claudia; Kirk, Jeremy; Donaldson, Malcolm; Ivarsson, Sten-A; Söder, Olle; Roche, Edna; Hoey, Hilary; Juul, Anders; Ong, Ken K; Dunger, David B

2015-03-01

The wide heterogeneity in the early growth and metabolism of children born small for gestational age (SGA), both before and during GH therapy, may reflect common genetic variations related to insulin secretion or sensitivity. Combined multiallele single nucleotide polymorphism scores with known associations with insulin sensitivity or insulin secretion were analyzed for their relationships with spontaneous postnatal growth and first-year responses to GH therapy in 96 short SGA children. The insulin sensitivity allele score (GS-InSens) was positively associated with spontaneous postnatal weight gain (regression coefficient [B]: 0.12 SD scores per allele; 95% confidence interval [CI], 0.01-0.23; P = .03) and also in response to GH therapy with first-year height velocity (B: 0.18 cm/y per allele; 95% CI, 0.02-0.35; P = .03) and change in IGF-1 (B: 0.17 SD scores per allele; 95% CI, 0.00-0.32; P = .03). The association with first-year height velocity was independent of reported predictors of response to GH therapy (adjusted P = .04). The insulin secretion allele score (GS-InSec) was positively associated with spontaneous postnatal height gain (B: 0.15; 95% CI, 0.01-0.30; P = .03) and disposition index both before (B: 0.02; 95% CI, 0.00-0.04; P = .04) and after 1 year of GH therapy (B: 0.03; 95% CI, 0.01-0.05; P = .002), but not with growth and IGF-1 responses to GH therapy. Neither of the allele scores was associated with size at birth. Genetic allele scores indicative of insulin sensitivity and insulin secretion were associated with spontaneous postnatal growth and responses to GH therapy in short SGA children. Further pharmacogenetic studies may support the rationale for adjuvant therapies by informing the mechanisms of treatment response.

3D printed microneedles for insulin skin delivery.

PubMed

Pere, Cristiane Patricia Pissinato; Economidou, Sophia N; Lall, Gurprit; Ziraud, Clémentine; Boateng, Joshua S; Alexander, Bruce D; Lamprou, Dimitrios A; Douroumis, Dennis

2018-06-15

In this study, polymeric microneedle patches were fabricated by stereolithography, a 3D printing technique, for the transdermal delivery of insulin. A biocompatible resin was photopolymerized to build pyramid and cone microneedle designs followed by inkjet print coating of insulin formulations. Trehalose, mannitol and xylitol were used as drug carriers with the aim to preserve insulin integrity and stability but also to facilitate rapid release rates. Circular dichroism and Raman analysis demonstrated that all carriers maintained the native form of insulin, with xylitol presenting the best performance. Franz cell release studies were used for in vitro determination of insulin release rates in porcine skin. Insulin was released rapidly within 30 min irrespectively of the microneedle design. 3D printing was proved an effective technology for the fabrication of biocompatible and scalable microneedle patches. Copyright © 2018 Elsevier B.V. All rights reserved.

Murine Norovirus Increases Atherosclerotic Lesion Size and Macrophages in Ldlr−/− Mice

PubMed Central

Paik, Jisun; Fierce, Yvette; Mai, Phuong-Oanh; Phelps, Susan R; McDonald, Thomas; Treuting, Piper; Drivdahl, Rolf; Brabb, Thea; LeBoeuf, Renee; O'Brien, Kevin D

2011-01-01

Murine norovirus (MNV) is prevalent in rodent facilities in the United States. Because MNV has a tropism for macrophages and dendritic cells, we hypothesized that it may alter phenotypes of murine models of inflammatory diseases, such as obesity and atherosclerosis. We examined whether MNV infection influences phenotypes associated with diet-induced obesity and atherosclerosis by using Ldlr−/− mice. Male Ldlr−/− mice were maintained on either a diabetogenic or high-fat diet for 16 wk, inoculated with either MNV or vehicle, and monitored for changes in body weight, blood glucose, glucose tolerance, and insulin sensitivity. Influence of MNV on atherosclerosis was analyzed by determining aortic sinus lesion area. Under both dietary regimens, MNV-infected and control mice gained similar amounts of weight and developed similar degrees of insulin resistance. However, MNV infection was associated with significant increases in aortic sinus lesion area and macrophage content in Ldlr−/− mice fed a high-fat diet but not those fed a diabetogenic diet. In conclusion, MNV infection exacerbates atherosclerosis in Ldlr−/− mice fed a high-fat diet but does not influence obesity- and diabetes-related phenotypes. Increased lesion size was associated with increased macrophages, suggesting that MNV may influence macrophage activation or accumulation in the lesion area. PMID:22330248

Oral Insulin Delivery: How Far Are We?

PubMed Central

Fonte, Pedro; Araújo, Francisca; Reis, Salette; Sarmento, Bruno

2013-01-01

Oral delivery of insulin may significantly improve the quality of life of diabetes patients who routinely receive insulin by the subcutaneous route. In fact, compared with this administration route, oral delivery of insulin in diabetes treatment offers many advantages: higher patient compliance, rapid hepatic insulinization, and avoidance of peripheral hyperinsulinemia and other adverse effects such as possible hypoglycemia and weight gain. However, the oral delivery of insulin remains a challenge because its oral absorption is limited. The main barriers faced by insulin in the gastrointestinal tract are degradation by proteolytic enzymes and lack of transport across the intestinal epithelium. Several strategies to deliver insulin orally have been proposed, but without much clinical or commercial success. Protein encapsulation into nanoparticles is regarded as a promising alternative to administer insulin orally because they have the ability to promote insulin paracellular or transcellular transport across the intestinal mucosa. In this review, different delivery systems intended to increase the oral bioavailability of insulin will be discussed, with a special focus on nanoparticulate carrier systems, as well as the efforts that pharmaceutical companies are making to bring to the market the first oral delivery system of insulin. The toxicological and safety data of delivery systems, the clinical value and progress of oral insulin delivery, and the future prospects in this research field will be also scrutinized. PMID:23567010

The effects of resistance training on metabolic health with weight regain.

PubMed

Warner, Shana O; Linden, Melissa A; Liu, Ying; Harvey, Benjamin R; Thyfault, John P; Whaley-Connell, Adam T; Chockalingam, Anand; Hinton, Pamela S; Dellsperger, Kevin C; Thomas, Tom R

2010-01-01

To determine whether resistance training effectively maintains improvements in cardiometabolic syndrome risk factors during weight regain, 9 individuals lost 4% to 6% of their body weight during an 8- to 12-week diet- and aerobic exercise-induced weight loss phase followed by a controlled weight regain phase (8-12 weeks), during which they regained approximately 50% of the lost weight while participating in a supervised resistance training program. Following weight loss (6.0%+/-0.3%), body mass index, body fat percentage, waist circumference, all abdominal adipose tissue depots, total cholesterol, low-density lipoprotein cholesterol, insulin, and homeostasis model assessment (HOMA) were significantly reduced, while quantitative insulin-sensitivity check index (QUICKI) and cardiorespiratory fitness (maximal oxygen consumption) significantly increased. During weight regain (48.3%+/-3.3% of lost weight), body fat percentage, waist circumference, and maximal oxygen consumption were maintained and muscular strength and lean body mass significantly increased. Abdominal adipose tissue depots, insulin, HOMA, and QUICKI did not significantly change after weight regain. Resistance training was effective in maintaining improvements in metabolic health during weight regain.

Effect of combined application insulin and insulin detemir on continous glucose monitor in children with type 1 diabetes mellitus.

PubMed

Chen, Xiao-Yun; Dong, Qing; Li, Gui-Mei

2015-01-01

Insulin detemir is a soluble long-acting human insulin analogue at neutral pH with a unique mechanism of action, which could strengthen the effects of insulin. This study aims to explore the effects of insulin combined with insulin detemir on the continous glucose in children with type 1 diabetes mellitus. In this study, 150 patients with type 1 diabetes enrolled were included and randomly divided into 3 groups: insulin group (group A), insulin detemir group (group B) and insulin combined with insulin detemir group (group C). Each subject underwent 72 h of continuous glucose monitoring (CGM). MAGE, HbA1c and Noctumal Hypoglycemia levels were examined by using the ELISA kits. The body weight changes were also detected in this study. The results indicated that the information including age, body weight, disease duration and glucose level and HbA1c percentage on the start time point among three groups indicated no statistical differences. Insulin combined with insulin detemir decrease MAGE and HbA1c level in Group C compared to Group A and Group A (P < 0.05). Insulin combined with insulin detemir decreas noctumal hypoglycemia levels and body weight changes (P < 0.05). In conclusion, this study confirmed efficacy of insulin detemir by demonstrating non-inferiority of insulin detemir compared with insulin with respect to HbA1c, with an improved safety profile including significantly fewer hypoglycaemic episodes and less undesirable weight gain in children.

A high-fat, ketogenic diet causes hepatic insulin resistance in mice, despite increasing energy expenditure and preventing weight gain.

PubMed

Jornayvaz, François R; Jurczak, Michael J; Lee, Hui-Young; Birkenfeld, Andreas L; Frederick, David W; Zhang, Dongyang; Zhang, Xian-Man; Samuel, Varman T; Shulman, Gerald I

2010-11-01

Low-carbohydrate, high-fat ketogenic diets (KD) have been suggested to be more effective in promoting weight loss than conventional caloric restriction, whereas their effect on hepatic glucose and lipid metabolism and the mechanisms by which they may promote weight loss remain controversial. The aim of this study was to explore the role of KD on liver and muscle insulin sensitivity, hepatic lipid metabolism, energy expenditure, and food intake. Using hyperinsulinemic-euglycemic clamps, we studied insulin action in mice fed a KD or regular chow (RC). Body composition was assessed by ¹H magnetic resonance spectroscopy. Despite being 15% lighter (P < 0.001) than RC-fed mice because of a 17% increase in energy expenditure (P < 0.001), KD-fed mice manifested severe hepatic insulin resistance, as reflected by decreased suppression (0% vs. 100% in RC-fed mice, P < 0.01) of endogenous glucose production during the clamp. Hepatic insulin resistance could be attributed to a 350% increase in hepatic diacylglycerol content (P < 0.001), resulting in increased activation of PKCε (P < 0.05) and decreased insulin receptor substrate-2 tyrosine phosphorylation (P < 0.01). Food intake was 56% (P < 0.001) lower in KD-fed mice, despite similar caloric intake, and could partly be attributed to a more than threefold increase (P < 0.05) in plasma N-acylphosphatidylethanolamine concentrations. In conclusion, despite preventing weight gain in mice, KD induces hepatic insulin resistance secondary to increased hepatic diacylglycerol content. Given the key role of nonalcoholic fatty liver disease in the development of type 2 diabetes and the widespread use of KD for the treatment of obesity, these results may have potentially important clinical implications.

Role of Substance P in the Regulation of Glucose Metabolism via Insulin Signaling-Associated Pathways

PubMed Central

Bakirtzi, Kyriaki; Kokkotou, Efi; Stavrakis, Dimitris; Margolis, Kara Gross; Thomou, Thomas; Giorgadze, Nino; Kirkland, James L.

2011-01-01

Substance P (SP), encoded by the tachykinin 1 (Tac1) gene, is the most potent tachykinin ligand for the high-affinity neurokinin-1 receptor (NK-1R). We previously reported that NK-1R-deficient mice show less weight gain and reduced circulating levels of leptin and insulin in response to a high-fat diet (HFD) and demonstrated the presence of functional NK-1R in isolated human preadipocytes. Here we assessed the effects of SP on weight gain in response to HFD and determined glucose metabolism in Tac1-deficient (Tac1−/−) mice. The effect of SP on the expression of molecules that may predispose to reduced glucose uptake was also determined in isolated human mesenteric, omental, and sc preadipocytes. We show that although weight accumulation in response to HFD was similar between Tac1−/− mice and wild-type littermates, Tac1−/− mice demonstrated lower glucose and leptin and increased adiponectin blood levels and showed improved responses to insulin challenge after HFD. SP stimulated phosphorylation of c-Jun N-terminal kinase, protein kinase Cθ, mammalian target of rapamycin, and inhibitory serine insulin receptor substrate-1 phosphorylation in human preadipocytes in vitro. Preincubation of human mesenteric preadipocytes with the protein kinase Cθ pseudosubstrate inhibitor reduced insulin receptor substrate 1 phosphorylation in response to SP. Lastly, SP also induced insulin receptor substrate-1 phosphorylation in mature human sc adipocytes. Our results demonstrate an important role for SP in adipose tissue responses and obesity-associated pathologies. These novel SP effects on molecules that enhance insulin resistance at the adipocyte level may reflect an important role for this peptide in the pathophysiology of type 2 diabetes. PMID:22009727

Role of substance P in the regulation of glucose metabolism via insulin signaling-associated pathways.

PubMed

Karagiannides, Iordanes; Bakirtzi, Kyriaki; Kokkotou, Efi; Stavrakis, Dimitris; Margolis, Kara Gross; Thomou, Thomas; Giorgadze, Nino; Kirkland, James L; Pothoulakis, Charalabos

2011-12-01

Substance P (SP), encoded by the tachykinin 1 (Tac1) gene, is the most potent tachykinin ligand for the high-affinity neurokinin-1 receptor (NK-1R). We previously reported that NK-1R-deficient mice show less weight gain and reduced circulating levels of leptin and insulin in response to a high-fat diet (HFD) and demonstrated the presence of functional NK-1R in isolated human preadipocytes. Here we assessed the effects of SP on weight gain in response to HFD and determined glucose metabolism in Tac1-deficient (Tac1(-/-)) mice. The effect of SP on the expression of molecules that may predispose to reduced glucose uptake was also determined in isolated human mesenteric, omental, and sc preadipocytes. We show that although weight accumulation in response to HFD was similar between Tac1(-/-) mice and wild-type littermates, Tac1(-/-) mice demonstrated lower glucose and leptin and increased adiponectin blood levels and showed improved responses to insulin challenge after HFD. SP stimulated phosphorylation of c-Jun N-terminal kinase, protein kinase C, mammalian target of rapamycin, and inhibitory serine insulin receptor substrate-1 phosphorylation in human preadipocytes in vitro. Preincubation of human mesenteric preadipocytes with the protein kinase C pseudosubstrate inhibitor reduced insulin receptor substrate 1 phosphorylation in response to SP. Lastly, SP also induced insulin receptor substrate-1 phosphorylation in mature human sc adipocytes. Our results demonstrate an important role for SP in adipose tissue responses and obesity-associated pathologies. These novel SP effects on molecules that enhance insulin resistance at the adipocyte level may reflect an important role for this peptide in the pathophysiology of type 2 diabetes.

Tracking Weight Change, Insulin Resistance, Stress, and Aerobic Fitness over 4 Years of College

ERIC Educational Resources Information Center

Hopper, Mari K.; Moninger, Shana Lynn

2017-01-01

Objective: To determine if weight gain is accompanied by development of insulin resistance (IR) during 4 years in college. Participants: Two cohorts of college students were enrolled in fall semesters 2009 and 2010 and tracked for 4 years. Methods: Following a 12-hour fast, subjects reported for measurement of body mass index (BMI), perceived…

Food Overconsumption in Healthy Adults Triggers Early and Sustained Increases in Serum Branched-Chain Amino Acids and Changes in Cysteine Linked to Fat Gain.

PubMed

Elshorbagy, Amany K; Samocha-Bonet, Dorit; Jernerén, Fredrik; Turner, Cheryl; Refsum, Helga; Heilbronn, Leonie K

2018-06-13

Plasma concentrations of branched-chain amino acids (BCAAs) and the sulfur-containing amino acid cysteine are associated with obesity and insulin resistance. BCAAs predict future diabetes. We investigated amino acid changes during food overconsumption. Forty healthy men and women with a body mass index (mean ± SEM) of 25.6 ± 0.6 were overfed by 1250 kcal/d for 28 d, increasing consumption of all macronutrients. Insulin sensitivity and body composition were assessed at baseline (day 0) and day 28. Fasting serum amino acids were measured at days 0, 3, and 28. Linear mixed-effects models evaluated the effect of time in the total group and separately in those with low and high body fat gain (below compared with at or above median fat gain, 1.95 kg). At days 0 and 28, insulin-induced suppression of serum amino acids during a hyperinsulinemic-euglycemic clamp test and, in a subset (n = 20), adipose tissue mRNA expression of selected amino acid metabolizing enzymes were assessed. Weight increased by 2.8 kg. High fat gainers gained 2.6 kg fat mass compared with 1.1 kg in low fat gainers. Valine and isoleucine increased at day 3 (+17% and +22%, respectively; P ≤ 0.002) and remained elevated at day 28, despite a decline in valine (P = 0.019) from day 3 values. Methionine, cystathionine, and taurine were unaffected. Serum total cysteine (tCys) transiently increased at day 3 (+11%; P = 0.022) only in high fat gainers (P-interaction = 0.043), in whom the cysteine catabolic enzyme cysteine dioxygenase (CDO1) was induced (+26%; P = 0.025) in adipose tissue (P-interaction = 0.045). Overconsumption did not alter adipose tissue mRNA expression of the BCAA-metabolizing enzymes branched-chain keto acid dehydrogenase E1α polypeptide (BCKDHA) or branched-chain amino transferase 1 (BCAT1). In the total population at day 0, insulin infusion decreased all serum amino acids (-11% to -47%; P < 0.01), except for homocysteine and tCys, which were unchanged, and glutathione, which was increased by 54%. At day 28, insulin increased tCys (+8%), and the insulin-induced suppression of taurine and phenylalanine observed at day 0, but not that of BCAAs, was significantly impaired. These findings highlight the role of nutrient oversupply in increasing fasting BCAA concentrations in healthy adults. The link between cysteine availability, CDO1 expression, and fat gain deserves investigation. This trial was registered at www.clinicaltrials.gov as NCT00562393.

Interferon beta overexpression attenuates adipose tissue inflammation and high-fat diet-induced obesity and maintains glucose homeostasis.

PubMed

Alsaggar, M; Mills, M; Liu, D

2017-01-01

The worldwide prevalence of obesity is increasing, raising health concerns regarding obesity-related complications. Chronic inflammation has been characterized as a major contributor to the development of obesity and obesity-associated metabolic disorders. The purpose of the current study is to assess whether the overexpression of interferon beta (IFNβ1), an immune-modulating cytokine, will attenuate high-fat diet-induced adipose inflammation and protect animals against obesity development. Using hydrodynamic gene transfer to elevate and sustain blood concentration of IFNβ1 in mice fed a high-fat diet, we showed that the overexpression of Ifnβ1 gene markedly suppressed immune cell infiltration into adipose tissue, and attenuated production of pro-inflammatory cytokines. Systemically, IFNβ1 blocked adipose tissue expansion and body weight gain, independent of food intake. Possible browning of white adipose tissue might also contribute to blockade of weight gain. More importantly, IFNβ1 improved insulin sensitivity and glucose homeostasis. These results suggest that targeting inflammation represents a practical strategy to block the development of obesity and its related pathologies. In addition, IFNβ1-based therapies have promising potential for clinical applications for the prevention and treatment of various inflammation-driven pathologies.

Polycystic ovary syndrome: insight into pathogenesis and a common association with insulin resistance.

PubMed

Barber, Thomas M; Dimitriadis, George K; Andreou, Avgi; Franks, Stephen

2015-12-01

Polycystic ovary syndrome (PCOS) is a common condition that typically develops in reproductive-age women. The cardinal clinical and biochemical characteristics of PCOS include reproductive dysfunction and hyperandrogenic features. PCOS is also strongly associated with obesity based on data from epidemiological and genetic studies. Accordingly, PCOS often becomes manifest in those women who carry a genetic predisposition to its development, and who also gain weight. The role of weight gain and obesity in the development of PCOS is mediated at least in part, through worsening of insulin resistance. Compensatory hyperinsulinaemia that develops in this context disrupts ovarian function, with enhanced androgen production and arrest of ovarian follicular development. Insulin resistance also contributes to the strong association of PCOS with adverse metabolic risk, including dysglycaemia, dyslipidaemia and fatty liver. Conversely, modest weight loss of just 5% body weight with improvement in insulin sensitivity, frequently results in clinically meaningful improvements in hyperandrogenic, reproductive and metabolic features. Future developments of novel therapies for obese women with PCOS should focus on promotion of weight loss and improvement in insulin sensitivity. In this context, therapies that complement lifestyle changes such as dietary modification and exercise, particularly during the maintenance phase of weight loss are important. Putative novel targets for therapy in PCOS include human brown adipose tissue. © Royal College of Physicians 2015. All rights reserved.

Beneficial effects of exercise on offspring obesity and insulin resistance are reduced by maternal high-fat diet

PubMed Central

Schreiber, Saskia; Klaus, Susanne; Kanzleiter, Isabel

2017-01-01

Scope We investigated the long-term effects of maternal high-fat consumption and post-weaning exercise on offspring obesity susceptibility and insulin resistance. Methods C57BL/6J dams were fed either a high-fat (HFD, 40% kcal fat) or low-fat (LFD, 10% kcal fat) semi-synthetic diet during pregnancy and lactation. After weaning, male offspring of both maternal diet groups (mLFD; mHFD) received a LFD. At week 7, half of the mice got access to a running wheel (+RW) as voluntary exercise training. To induce obesity, all offspring groups (mLFD +/-RW and mHFD +/-RW) received HFD from week 15 until week 25. Results Compared to mLFD, mHFD offspring were more prone to HFD-induced body fat gain and exhibited an increased liver mass which was not due to increased hepatic triglyceride levels. RW improved the endurance capacity in mLFD, but not in mHFD offspring. Additionally, mHFD offspring +RW exhibited higher plasma insulin levels during glucose tolerance test and an elevated basal pancreatic insulin production compared to mLFD offspring. Conclusion Taken together, maternal HFD reduced offspring responsiveness to the beneficial effects of voluntary exercise training regarding the improvement of endurance capacity, reduction of fat mass gain, and amelioration of HFD-induced insulin resistance. PMID:28235071

Postnatal Weight Gain Modifies Severity and Functional Outcome of Oxygen-Induced Proliferative Retinopathy

PubMed Central

Stahl, Andreas; Chen, Jing; Sapieha, Przemyslaw; Seaward, Molly R.; Krah, Nathan M.; Dennison, Roberta J.; Favazza, Tara; Bucher, Felicitas; Löfqvist, Chatarina; Ong, Huy; Hellström, Ann; Chemtob, Sylvain; Akula, James D.; Smith, Lois E.H.

2010-01-01

In clinical studies, postnatal weight gain is strongly associated with retinopathy of prematurity (ROP). However, animal studies are needed to investigate the pathophysiological mechanisms of how postnatal weight gain affects the severity of ROP. In the present study, we identify nutritional supply as one potent parameter that affects the extent of retinopathy in mice with identical birth weights and the same genetic background. Wild-type pups with poor postnatal nutrition and poor weight gain (PWG) exhibit a remarkably prolonged phase of retinopathy compared to medium weight gain or extensive weight gain pups. A high (r2 = 0.83) parabolic association between postnatal weight gain and oxygen-induced retinopathy severity is observed, as is a significantly prolonged phase of proliferative retinopathy in PWG pups (20 days) compared with extensive weight gain pups (6 days). The extended retinopathy is concomitant with prolonged overexpression of retinal vascular endothelial growth factor in PWG pups. Importantly, PWG pups show low serum levels of nonfasting glucose, insulin, and insulin-like growth factor-1 as well as high levels of ghrelin in the early postoxygen-induced retinopathy phase, a combination indicative of poor metabolic supply. These differences translate into visual deficits in adult PWG mice, as demonstrated by impaired bipolar and proximal neuronal function. Together, these results provide evidence for a pathophysiological correlation between poor postnatal nutritional supply, slow weight gain, prolonged retinal vascular endothelial growth factor overexpression, protracted retinopathy, and reduced final visual outcome. PMID:21056995

Postnatal weight gain modifies severity and functional outcome of oxygen-induced proliferative retinopathy.

PubMed

Stahl, Andreas; Chen, Jing; Sapieha, Przemyslaw; Seaward, Molly R; Krah, Nathan M; Dennison, Roberta J; Favazza, Tara; Bucher, Felicitas; Löfqvist, Chatarina; Ong, Huy; Hellström, Ann; Chemtob, Sylvain; Akula, James D; Smith, Lois E H

2010-12-01

In clinical studies, postnatal weight gain is strongly associated with retinopathy of prematurity (ROP). However, animal studies are needed to investigate the pathophysiological mechanisms of how postnatal weight gain affects the severity of ROP. In the present study, we identify nutritional supply as one potent parameter that affects the extent of retinopathy in mice with identical birth weights and the same genetic background. Wild-type pups with poor postnatal nutrition and poor weight gain (PWG) exhibit a remarkably prolonged phase of retinopathy compared to medium weight gain or extensive weight gain pups. A high (r(2) = 0.83) parabolic association between postnatal weight gain and oxygen-induced retinopathy severity is observed, as is a significantly prolonged phase of proliferative retinopathy in PWG pups (20 days) compared with extensive weight gain pups (6 days). The extended retinopathy is concomitant with prolonged overexpression of retinal vascular endothelial growth factor in PWG pups. Importantly, PWG pups show low serum levels of nonfasting glucose, insulin, and insulin-like growth factor-1 as well as high levels of ghrelin in the early postoxygen-induced retinopathy phase, a combination indicative of poor metabolic supply. These differences translate into visual deficits in adult PWG mice, as demonstrated by impaired bipolar and proximal neuronal function. Together, these results provide evidence for a pathophysiological correlation between poor postnatal nutritional supply, slow weight gain, prolonged retinal vascular endothelial growth factor overexpression, protracted retinopathy, and reduced final visual outcome.

Insulin Is Required to Maintain Albumin Expression by Inhibiting Forkhead Box O1 Protein*

PubMed Central

Chen, Qing; Lu, Mingjian; Monks, Bobby R.; Birnbaum, Morris J.

2016-01-01

Diabetes is accompanied by dysregulation of glucose, lipid, and protein metabolism. In recent years, much effort has been spent on understanding how insulin regulates glucose and lipid metabolism, whereas the effect of insulin on protein metabolism has received less attention. In diabetes, hepatic production of serum albumin decreases, and it has been long established that insulin positively controls albumin gene expression. In this study, we used a genetic approach in mice to identify the mechanism by which insulin regulates albumin gene transcription. Albumin expression was decreased significantly in livers with insulin signaling disrupted by ablation of the insulin receptor or Akt. Concomitant deletion of Forkhead Box O1 (Foxo1) in these livers rescued the decreased albumin secretion. Furthermore, activation of Foxo1 in the liver is sufficient to suppress albumin expression. These results suggest that Foxo1 acts as a repressor of albumin expression. PMID:26668316

Rosiglitazone Improves Insulin Sensitivity and Baroreflex Gain in Rats with Diet-Induced Obesity

PubMed Central

Zhao, Ding; McCully, Belinda H.

2012-01-01

Obesity decreases baroreflex gain (BRG); however, the mechanisms are unknown. We tested the hypothesis that impaired BRG is related to the concurrent insulin resistance, and, therefore, BRG would be improved after treatment with the insulin-sensitizing drug rosiglitazone. Male rats fed a high-fat diet diverged into obesity-prone (OP) and obesity-resistant (OR) groups after 2 weeks. Then, OP and OR rats, as well as control (CON) rats fed a standard diet, were treated daily for 2 to 3 weeks with rosiglitazone (3 or 6 mg/kg) or its vehicle by gavage. Compared with OR and CON rats, conscious OP rats exhibited reductions in BRG (OP, 2.9 ± 0.1 bpm/mm Hg; OR, 4.0 ± 0.2 bpm/mm Hg; CON, 3.9 ± 0.2 bpm/mm Hg; P < 0.05) and insulin sensitivity (hyperinsulinemic euglycemic clamp; OP, 6.8 ± 0.9 mg/kg · min; OR, 22.2 ± 1.2 mg/kg · min; CON, 17.7 ± 0.8 mg/kg · min; P < 0.05), which were well correlated (r2 = 0.49; P < 0.01). In OP rats, rosiglitazone dose-dependently improved (P < 0.05) insulin sensitivity (12.8 ± 0.6 mg/kg · min at 3 mg/kg; 16.0 ± 1.5 mg/kg · min at 6 mg/kg) and BRG (3.8 ± 0.4 bpm/mm Hg at 3 mg/kg; 5.3 ± 0.7 bpm/mm Hg at 6 mg/kg). However, 6 mg/kg rosiglitazone also increased BRG in OR rats without increasing insulin sensitivity, disrupted the correlation between BRG and insulin sensitivity (r2 = 0.08), and, in OP and OR rats, elevated BRG relative to insulin sensitivity (analysis of covariance; P < 0.05). Moreover, in OP rats, stimulation of the aortic depressor nerve, to activate central baroreflex pathways, elicited markedly reduced decreases in heart rate and arterial pressure, but these responses were not improved by rosiglitazone. In conclusion, diet-induced obesity impairs BRG via a central mechanism that is related to the concurrent insulin resistance. Rosiglitazone normalizes BRG, but not by improving brain baroreflex processing or insulin sensitivity. PMID:22815534

Infant Body Composition and Adipokine Concentrations in Relation to Maternal Gestational Weight Gain

PubMed Central

Estampador, Angela C.; Pomeroy, Jeremy; Renström, Frida; Nelson, Scott M.; Mogren, Ingrid; Persson, Margareta; Sattar, Naveed; Domellöf, Magnus; Franks, Paul W.

2014-01-01

OBJECTIVE To investigate associations of maternal gestational weight gain and body composition and their impact on offspring body composition and adipocytokine, glucose, and insulin concentrations at age 4 months. RESEARCH DESIGN AND METHODS This was a prospective study including 31 mother-infant pairs (N = 62). Maternal body composition was assessed using doubly labeled water. Infant body composition was assessed at 4 months using air displacement plethysmography, and venous blood was assayed for glucose, insulin, adiponectin, interleukin-6 (IL-6), and leptin concentrations. RESULTS Rate of gestational weight gain in midpregnancy was significantly associated with infant fat mass (r = 0.41, P = 0.03); rate of gestational weight in late pregnancy was significantly associated with infant fat-free mass (r = 0.37, P = 0.04). Infant birth weight was also strongly correlated with infant fat-free mass at 4 months (r = 0.63, P = 0.0002). Maternal BMI and maternal fat mass were strongly inversely associated with infant IL-6 concentrations (r = −0.60, P = 0.002 and r = −0.52, P = 0.01, respectively). Infant fat-free mass was inversely related to infant adiponectin concentrations (r = −0.48, P = 0.008) and positively correlated with infant blood glucose adjusted for insulin concentrations (r = 0.42, P = 0.04). No significant associations for leptin were observed. CONCLUSIONS Timing of maternal weight gain differentially impacts body composition of the 4-month-old infant, which in turn appears to affect the infant’s glucose and adipokine concentrations. PMID:24623025

Biphasic insulin-releasing effect of BTS 67 582 in rats.

PubMed

Storey, D A; Bailey, C J

1998-12-01

BTS 67 582 (1,1-dimethyl-2(2-morpholinophenyl)guanidine fumarate) is being developed as a short-acting anti-diabetic insulin secretagogue. The effect of BTS 67 582 on the phasic pattern of insulin release was assessed in anaesthetized normal rats by measuring arterial plasma insulin concentrations while arterial glucose concentrations were fixed at 6, 8.5 and 12.5 mM. Intravenous BTS 67 582 (10 mg kg(-1)) induced an immediate but transient increase in insulin concentrations which declined by 10 min (first phase). This was followed by a smaller but sustained increase in insulin concentrations (second phase). The increment from basal to peak insulin release (0-2 min) was independent of glucose, but the first phase was maintained for longer and the second phase was greater at the highest concentration of glucose (12.5 mM). BTS 67 582 also extended the first-phase insulin response to a standard intravenous glucose challenge and enhanced the rate of glucose disappearance by approximately 12%. Thus BTS 67 582 causes biphasic stimulation of insulin release and augments the insulin-releasing effect of glucose.

FoxO1 integrates direct and indirect effects of insulin on hepatic glucose production and glucose utilization

PubMed Central

O-Sullivan, InSug; Zhang, Wenwei; Wasserman, David H.; Liew, Chong Wee; Liu, Jonathan; Paik, Jihye; DePinho, Ronald A.; Stolz, Donna Beer; Kahn, C. Ronald; Schwartz, Michael W.; Unterman, Terry G.

2016-01-01

FoxO proteins are major targets of insulin action. To better define the role of FoxO1 in mediating insulin effects in the liver, we generated liver-specific insulin receptor knockout (LIRKO) and IR/FoxO1 double knockout (LIRFKO) mice. Here we show that LIRKO mice are severely insulin resistant based on glucose, insulin and C-peptide levels, and glucose and insulin tolerance tests, and genetic deletion of hepatic FoxO1 reverses these effects. 13C-glucose and insulin clamp studies indicate that regulation of both hepatic glucose production (HGP) and glucose utilization is impaired in LIRKO mice, and these defects are also restored in LIRFKO mice corresponding to changes in gene expression. We conclude that (1) inhibition of FoxO1 is critical for both direct (hepatic) and indirect effects of insulin on HGP and utilization, and (2) extrahepatic effects of insulin are sufficient to maintain normal whole-body and hepatic glucose metabolism when liver FoxO1 activity is disrupted. PMID:25963540

Sustained efficacy of insulin pump therapy compared with multiple daily injections in type 2 diabetes: 12-month data from the OpT2mise randomized trial.

PubMed

Aronson, R; Reznik, Y; Conget, I; Castañeda, J A; Runzis, S; Lee, S W; Cohen, O

2016-05-01

To compare insulin pump therapy and multiple daily injections (MDI) in patients with type 2 diabetes receiving basal and prandial insulin analogues. After a 2-month dose-optimization period, 331 patients with glycated haemoglobin (HbA1c) levels ≥8.0% and ≤12% were randomized to pump therapy or continued MDI for 6 months [randomization phase (RP)]. The MDI group was subsequently switched to pump therapy during a 6-month continuation phase (CP). The primary endpoint was the between-group difference in change in mean HbA1c from baseline to the end of the RP. The mean HbA1c at baseline was 9% in both groups. At the end of the RP, the reduction in HbA1c was significantly greater with pump therapy than with MDI (-1.1 ± 1.2% vs -0.4 ± 1.1%; p < 0.001). The pump therapy group maintained this improvement to 12 months while the MDI group, which was switched to pump therapy, showed a 0.8% reduction: the final HbA1c level was identical in both arms. In the RP, total daily insulin dose (TDD) was 20.4% lower with pump therapy than with MDI and remained stable in the CP. The MDI-pump group showed a 19% decline in TDD, such that by 12 months TDD was equivalent in both groups. There were no differences in weight gain or ketoacidosis between groups. In the CP, one patient in each group experienced severe hypoglycaemia. Pump therapy has a sustained durable effect on glycaemic control in uncontrolled type 2 diabetes. © 2016 The Authors. Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.

Sustained efficacy of insulin pump therapy compared with multiple daily injections in type 2 diabetes: 12‐month data from the OpT2mise randomized trial

PubMed Central

Reznik, Y.; Conget, I.; Castañeda, J. A.; Runzis, S.; Lee, S. W.; Cohen, O.

2016-01-01

Aims To compare insulin pump therapy and multiple daily injections (MDI) in patients with type 2 diabetes receiving basal and prandial insulin analogues. Methods After a 2‐month dose‐optimization period, 331 patients with glycated haemoglobin (HbA1c) levels ≥8.0% and ≤12% were randomized to pump therapy or continued MDI for 6 months [randomization phase (RP)]. The MDI group was subsequently switched to pump therapy during a 6‐month continuation phase (CP). The primary endpoint was the between‐group difference in change in mean HbA1c from baseline to the end of the RP. Results The mean HbA1c at baseline was 9% in both groups. At the end of the RP, the reduction in HbA1c was significantly greater with pump therapy than with MDI (−1.1 ± 1.2% vs −0.4 ± 1.1%; p < 0.001). The pump therapy group maintained this improvement to 12 months while the MDI group, which was switched to pump therapy, showed a 0.8% reduction: the final HbA1c level was identical in both arms. In the RP, total daily insulin dose (TDD) was 20.4% lower with pump therapy than with MDI and remained stable in the CP. The MDI–pump group showed a 19% decline in TDD, such that by 12 months TDD was equivalent in both groups. There were no differences in weight gain or ketoacidosis between groups. In the CP, one patient in each group experienced severe hypoglycaemia. Conclusions Pump therapy has a sustained durable effect on glycaemic control in uncontrolled type 2 diabetes. PMID:26854123

Evaluation of the Genetic and Nutritional Control of Obesity and Type 2 Diabetes in a Novel Mouse Model on Chromosome 7: An Insight into Insulin Signaling and Glucose Homeostasis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nelson, S.; Dhar, M.

Obesity is the main cause of type 2 diabetes, accounting for 90-95% of all diabetes cases in the US. Human obesity is a complex trait and can be studied using appropriate mouse models. A novel polygenic mouse model for studying the genetic and environmental contributions to and the physiological ramifications of obesity and related phenotypes is found in specific lines of mice bred and maintained at Oak Ridge National Laboratory. Heterozygous mice with a maternally inherited copy of two radiation-induced deletions in the p region of mouse chromosome 7, p23DFioD and p30PUb, have significantly greater body fat and show hyperinsulinemiamore » compared to the wild-type. A single gene, Atp10c, maps to this critical region and codes for a putative aminophospholipid translocase. Biochemical and molecular studies were initiated to gain insight into obesity and glucose homeostasis in these animals and to study the biological role of Atp10c in creating these phenotypes. Glucose and insulin tolerance tests were standardized for the heterozygous p23DFioD and control mice on a custom-made diet containing 20% protein, 70% carbohydrate, and 10% fat (kcal). Atp10c expression profiles were also generated using Reverse-Transcriptase Polymerase Chain Reaction (RT-PCR). Heterozygous p23DFioD animals showed insulin resistance after receiving a dose of either 0.375 or 0.75 U/kg Illetin R insulin. RT-PCR data also shows differences in Atp10c expression in the mutants versus control mice. Using these standardized biochemical assays, future studies will further the understanding of genetic and nutritional controls of glucose homeostasis and obesity in animal models and subsequently in human populations.« less

Enhanced leptin sensitivity and improved glucose homeostasis in mice lacking suppressor of cytokine signaling-3 in POMC-expressing cells.

PubMed

Kievit, Paul; Howard, Jane K; Badman, Michael K; Balthasar, Nina; Coppari, Roberto; Mori, Hiroyuki; Lee, Charlotte E; Elmquist, Joel K; Yoshimura, Akihiko; Flier, Jeffrey S

2006-08-01

Suppressor of cytokine signaling-3 (Socs-3) negatively regulates the action of various cytokines, as well as the metabolic hormones leptin and insulin. Mice with haploinsufficiency of Socs-3, or those with neuronal deletion of Socs-3, are lean and more leptin and insulin sensitive. To examine the role of Socs-3 within specific neurons critical to energy balance, we created mice with selective deletion of Socs-3 within pro-opiomelanocortin (POMC)-expressing cells. These mice had enhanced leptin sensitivity, measured by weight loss and food intake after leptin infusion. On chow diet, glucose homeostasis was improved despite normal weight gain. On a high-fat diet, the rate of weight gain was reduced, due to increased energy expenditure rather than decreased food intake; glucose homeostasis and insulin sensitivity were substantially improved. These studies demonstrate that Socs-3 within POMC neurons regulates leptin sensitivity and glucose homeostasis, and plays a key role in linking high-fat diet to disordered metabolism.

Seasonal changes in pancreatic B-cell function in euthermic yellow-bellied marmots.

PubMed

Florant, G L; Lawrence, A K; Williams, K; Bauman, W A

1985-08-01

Fasting plasma insulin (PI) and glucose (PG) concentrations were measured throughout the body weight cycle of marmots. Animals gained weight during summer, and in late fall body weight peaked, after which they ceased feeding. Each month euthermic animals were injected intra-arterially with either dextrose (500 mg/kg) or porcine insulin (0.1 U/kg), and blood samples were collected over the subsequent 2 h. During weight gain fasting PI concentration and pancreatic B-cell response to injected dextrose increased markedly. Maximal insulin release to a dextrose challenge was measured during peak body weight or when body weight initially began to decline. The PG concentration after exogenous insulin administration was slight (less than 10%) in the fall but increased approximately 25% in the spring after marmots lost weight. Basal PG levels were not significantly different throughout the year. Basal fasting PI concentrations were significantly higher during the fall (P less than 0.01). It is suggested that in the fall, when marmots are obese, hyperinsulinemia and peripheral insulin resistance appear. Furthermore, in two animals with an increase in body weight of approximately 30% or less over the summer, peripheral resistance was demonstrable, albeit not as marked as in animals that appropriately doubled their body weights when given food ad libitum. Thus we hypothesize that factors other than adiposity, i.e., food intake, central nervous system input to the pancreatic B-cell, and/or changes in B-cell sensitivity to PG, may contribute to the observed peripheral insulin resistance and may be involved in body weight regulation.

Diet-induced obesity alters memory consolidation in female rats.

PubMed

Zanini, P; Arbo, B D; Niches, G; Czarnabay, D; Benetti, F; Ribeiro, M F; Cecconello, A L

2017-10-15

Obesity is a multifactorial disease characterized by the abnormal or excessive fat accumulation, which is caused by an energy imbalance between consumed and expended calories. Obesity leads to an inflammatory response that may result in peripheral and central metabolic changes, including insulin and leptin resistance. Insulin and leptin resistance have been associated with metabolic and cognitive dysfunctions. Obesity and some neurodegenerative diseases that lead to dementia affect mainly women. However, the effects of diet-induced obesity on memory consolidation in female rats are poorly understood. Therefore, the aim of this study was to evaluate the effect of a hypercaloric diet on the object recognition memory of female rats and on possible related metabolic changes. The animals submitted to the hypercaloric diet presented a higher food intake in grams and in calories, resulting in increased weight gain and liposomatic index in comparison with the animals exposed to the control diet. These animals presented a memory deficit in the object recognition test and increased serum levels of glucose and leptin. However, no significant differences were found in the serum levels of insulin, TNF-α and IL-1β, in the index of insulin resistance (HOMA), in the hippocampal levels of insulin, TNF-α and IL-1β, as well as on Akt expression or activation in the hippocampus. Our findings indicate that adult female rats submitted to a hypercaloric diet present memory consolidation impairment, which could be associated with diet-induced weight gain and leptin resistance, even without the development of insulin resistance. Copyright © 2017 Elsevier Inc. All rights reserved.

Insulin Dynamics in Young Women with Polycystic Ovary Syndrome and Normal Glucose Tolerance across Categories of Body Mass Index

PubMed Central

Manco, Melania; Castagneto-Gissey, Lidia; Arrighi, Eugenio; Carnicelli, Annamaria; Brufani, Claudia; Luciano, Rosa; Mingrone, Geltrude

2014-01-01

Background Evidence favours insulin resistance and compensatory hyperinsulinemia as the predominant, perhaps primary, defects in polycystic ovary syndrome (PCOS). The aim of the present study was to evaluate insulin metabolism in young women with PCOS but normal glucose tolerance as compared with age, body mass index and insulin resistance-matched controls to answer the question whether women with PCOS hypersecrete insulin in comparison to appropriately insulin resistance-matched controls. Research Design and Methods Sixty-nine cases were divided according to their body mass index (BMI) in normal-weight (N = 29), overweight (N = 24) and obese patients (N = 16). Controls were 479 healthy women (age 16–49 y). Whole body Insulin Sensitivity (WBISI), fasting, and total insulin secretion were estimated following an oral glucose tolerance test (C-peptide deconvolution method). Results Across classes of BMI, PCOS patients had greater insulin resistance than matched controls (p<0.0001 for all the comparisons), but they showed higher fasting and total insulin secretion than their age, BMI and insulin resistance-matched peers (p<0.0001 for all the comparisons). Conclusion Women with PCOS show higher insulin resistance but also larger insulin secretion to maintain normal glucose homeostasis than age-, BMI- and insulin resistance-matched controls. PMID:24705280

Antidiabetogenic Effects of Chromium Mitigate Hyperinsulinemia-Induced Cellular Insulin Resistance via Correction of Plasma Membrane Cholesterol Imbalance

PubMed Central

Horvath, Emily M.; Tackett, Lixuan; McCarthy, Alicia M.; Raman, Priya; Brozinick, Joseph T.; Elmendorf, Jeffrey S.

2008-01-01

Previously, we found that a loss of plasma membrane (PM) phosphatidylinositol 4,5-bisphosphate (PIP2)-regulated filamentous actin (F-actin) structure contributes to insulin-induced insulin resistance. Interestingly, we also demonstrated that chromium picolinate (CrPic), a dietary supplement thought to improve glycemic status in insulin-resistant individuals, augments insulin-regulated glucose transport in insulin-sensitive 3T3-L1 adipocytes by lowering PM cholesterol. Here, to gain mechanistic understanding of these separate observations, we tested the prediction that CrPic would protect against insulin-induced insulin resistance by improving PM features important in cytoskeletal structure and insulin sensitivity. We found that insulin-induced insulin-resistant adipocytes display elevated PM cholesterol with a reciprocal decrease in PM PIP2. This lipid imbalance and insulin resistance was corrected by the cholesterol-lowering action of CrPic. The PM lipid imbalance did not impair insulin signaling, nor did CrPic amplify insulin signal transduction. In contrast, PM analyses corroborated cholesterol and PIP2 interactions influencing cytoskeletal structure. Because extensive in vitro study documents an essential role for cytoskeletal capacity in insulin-regulated glucose transport, we next evaluated intact skeletal muscle from obese, insulin-resistant Zucker (fa/fa) rats. Because insulin resistance in these animals likely involves multiple mechanisms, findings that cholesterol-lowering restored F-actin cytoskeletal structure and insulin sensitivity to that witnessed in lean control muscle were striking. Also, experiments using methyl-β-cyclodextrin to shuttle cholesterol into or out of membranes respectively recapitulated the insulin-induced insulin-resistance and protective effects of CrPic on membrane/cytoskeletal interactions and insulin sensitivity. These data predict a PM cholesterol basis for hyperinsulinemia-associated insulin resistance and importantly highlight the reversible nature of this abnormality. PMID:18165437

Childhood craniopharyngioma: greater hypothalamic involvement before surgery is associated with higher homeostasis model insulin resistance index

PubMed Central

Trivin, Christine; Busiah, Kanetee; Mahlaoui, Nizar; Recasens, Christophe; Souberbielle, Jean-Claude; Zerah, Michel; Sainte-Rose, Christian; Brauner, Raja

2009-01-01

Background Obesity seems to be linked to the hypothalamic involvement in craniopharyngioma. We evaluated the pre-surgery relationship between the degree of this involvement on magnetic resonance imaging and insulin resistance, as evaluated by the homeostasis model insulin resistance index (HOMA). As insulin-like growth factor 1, leptin, soluble leptin receptor (sOB-R) and ghrelin may also be involved, we compared their plasma concentrations and their link to weight change. Methods 27 children with craniopharyngioma were classified as either grade 0 (n = 7, no hypothalamic involvement), grade 1 (n = 8, compression without involvement), or grade 2 (n = 12, severe involvement). Results Despite having similar body mass indexes (BMI), the grade 2 patients had higher glucose, insulin and HOMA before surgery than the grade 0 (P = 0.02, <0.05 and 0.02 respectively) and 1 patients (P < 0.02 and <0.03 for both insulin and HOMA). The grade 0 (5.8 ± 4.9) and 1 (7.2 ± 5.3) patients gained significantly less weight (kg) during the year after surgery than did the grade 2 (16.3 ± 7.4) patients. The pre-surgery HOMA was positively correlated with these weight changes (P < 0.03). The data for the whole population before and 6–18 months after surgery showed increases in BMI (P < 0.0001), insulin (P < 0.005), and leptin (P = 0.0005), and decreases in sOB-R (P < 0.04) and ghrelin (P < 0.03). Conclusion The hypothalamic involvement by the craniopharyngioma before surgery seems to determine the degree of insulin resistance, regardless of the BMI. The pre-surgery HOMA values were correlated with the post-surgery weight gain. This suggests that obesity should be prevented by reducing inn secretion in those cases with hypothalamic involvement. PMID:19341477

Molecular aspects of glucose homeostasis in skeletal muscle--A focus on the molecular mechanisms of insulin resistance.

PubMed

Carnagarin, Revathy; Dharmarajan, Arun M; Dass, Crispin R

2015-12-05

Among all the varied actions of insulin, regulation of glucose homeostasis is the most critical and intensively studied. With the availability of glucose from nutrient metabolism, insulin action in muscle results in increased glucose disposal via uptake from the circulation and storage of excess, thereby maintaining euglycemia. This major action of insulin is executed by redistribution of the glucose transporter protein, GLUT4 from intracellular storage sites to the plasma membrane and storage of glucose in the form of glycogen which also involves modulation of actin dynamics that govern trafficking of all the signal proteins of insulin signal transduction. The cellular mechanisms responsible for these trafficking events and the defects associated with insulin resistance are largely enigmatic, and this review provides a consolidated overview of the various molecular mechanisms involved in insulin-dependent glucose homeostasis in skeletal muscle, as insulin resistance at this major peripheral site impacts whole body glucose homeostasis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Chronic central leptin infusion modulates the glycemia response to insulin administration in male rats through regulation of hepatic glucose metabolism.

PubMed

Burgos-Ramos, Emma; Canelles, Sandra; Rodríguez, Amaia; Gómez-Ambrosi, Javier; Frago, Laura M; Chowen, Julie A; Frühbeck, Gema; Argente, Jesús; Barrios, Vicente

2015-11-05

Leptin and insulin use overlapping signaling mechanisms to modify hepatic glucose metabolism, which is critical in maintaining normal glycemia. We examined the effect of an increase in central leptin and insulin on hepatic glucose metabolism and its influence on serum glucose levels. Chronic leptin infusion increased serum leptin and reduced hepatic SH-phosphotyrosine phosphatase 1, the association of suppressor of cytokine signaling 3 to the insulin receptor in liver and the rise in glycemia induced by central insulin. Leptin also decreased hepatic phosphoenolpyruvate carboxykinase levels and increased insulin's ability to phosphorylate insulin receptor substrate-1, Akt and glycogen synthase kinase on Ser9 and to stimulate glucose transporter 2 and glycogen levels. Peripheral leptin treatment reproduced some of these changes, but to a lesser extent. Our data indicate that leptin increases the hepatic response to a rise in insulin, suggesting that pharmacological manipulation of leptin targets may be of interest for controlling glycemia. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Effects of dietary fat profile on gut permeability and microbiota and their relationships with metabolic changes in mice.

PubMed

Lam, Yan Y; Ha, Connie W Y; Hoffmann, Jenny M A; Oscarsson, Jan; Dinudom, Anuwat; Mather, Thomas J; Cook, David I; Hunt, Nicholas H; Caterson, Ian D; Holmes, Andrew J; Storlien, Len H

2015-07-01

To distinguish the effects of dietary fat profile on gut parameters and their relationships with metabolic changes and to determine the capacity of n-3 fatty acids to modify gut variables in the context of diet-induced metabolic dysfunctions. Mice received control or high-fat diets emphasizing saturated (HFD-sat), n-6 (HFD-n6), or n-3 (HFD-n3) fatty acids for 8 weeks. In another cohort, mice that were maintained on HFD-sat received n-3-rich fish oil or resolvin D1 supplementation. HFD-sat and HFD-n6 induced similar weight gain, but only HFD-sat increased index of insulin resistance (HOMA-IR), colonic permeability, and mesenteric fat inflammation. Hydrogen sulfide-producing bacteria were one of the major groups driving the diet-specific changes in gut microbiome, with the overall microbial profile being associated with changes in body weight, HOMA-IR, and gut permeability. In mice maintained on HFD-sat, fish oil and resolvin D1 restored barrier function and reduced inflammation in the colon but were unable to normalize HOMA-IR. Different dietary fat profiles led to distinct intestinal and metabolic outcomes that are independent of obesity. Interventions targeting inflammation successfully restored gut health but did not reverse systemic aspects of diet-induced metabolic dysfunction, implicating separation between gut dysfunctions and disease-initiating and/or -maintaining processes. © 2015 The Obesity Society.

Aerobic exercise training conserves insulin sensitivity for 1 yr following weight loss in overweight women.

PubMed

Fisher, Gordon; Hunter, Gary R; Gower, Barbara A

2012-02-01

The objectives of this study were to 1) identify the independent effects of exercise (aerobic or resistance training) and weight loss on whole body insulin sensitivity and 2) determine if aerobic or resistance training would be more successful for maintaining improved whole body insulin sensitivity 1 yr following weight loss. Subjects were 97 healthy, premenopausal women, body mass index (BMI) 27-30 kg/m(2). Following randomized assignment to one of three groups, diet only, diet + aerobic, or diet + resistance training until a BMI <25 kg/m(2) was achieved, body composition, fat distribution, and whole body insulin sensitivity were determined at baseline, in the weight reduced state, and at 1-yr follow up. The whole body insulin sensitivity index (S(I)) was determined using a frequently sampled intravenous glucose tolerance test. Results of repeated-measures ANOVA indicated a significant improvement in S(I) following weight loss. However, there were no group or group×time interactions. At 1-yr follow up, there were no significant time or group interactions for S(I;) however, there was a significant group×time interaction for S(I). Post hoc analysis revealed that women in the aerobic training group showed a significant increased S(I) from weight reduced to 1-yr follow up (P < 0.05), which was independent of intra-abdominal adipose tissue and %fat. No significant differences in S(I) from weight reduced to 1-yr follow up were observed for diet only or diet + resistance groups. Additionally, multiple linear regression analysis revealed that change in whole body insulin sensitivity from baseline to 1-yr follow up was independently associated with the change in Vo(2max) from baseline to 1-yr follow up (P < 0.05). These results suggest that long-term aerobic exercise training may conserve improvements in S(I) following weight loss and that maintaining cardiovascular fitness following weight loss may be important for maintaining improvements in S(I).

Probiotic supplementation prevents high-fat, overfeeding-induced insulin resistance in human subjects.

PubMed

Hulston, Carl J; Churnside, Amelia A; Venables, Michelle C

2015-02-28

The purpose of the present study was to determine whether probiotic supplementation (Lactobacillus casei Shirota (LcS)) prevents diet-induced insulin resistance in human subjects. A total of seventeen healthy subjects were randomised to either a probiotic (n 8) or a control (n 9) group. The probiotic group consumed a LcS-fermented milk drink twice daily for 4 weeks, whereas the control group received no supplementation. Subjects maintained their normal diet for the first 3 weeks of the study, after which they consumed a high-fat (65 % of energy), high-energy (50 % increase in energy intake) diet for 7 d. Whole-body insulin sensitivity was assessed by an oral glucose tolerance test conducted before and after overfeeding. Body mass increased by 0·6 (SE 0·2) kg in the control group (P< 0·05) and by 0·3 (SE 0·2) kg in the probiotic group (P>0·05). Fasting plasma glucose concentrations increased following 7 d of overeating (control group: 5·3 (SE 0·1) v. 5·6 (SE 0·2) mmol/l before and after overfeeding, respectively, P< 0·05), whereas fasting serum insulin concentrations were maintained in both groups. Glucose AUC values increased by 10 % (from 817 (SE 45) to 899 (SE 39) mmol/l per 120 min, P< 0·05) and whole-body insulin sensitivity decreased by 27 % (from 5·3 (SE 1·4) to 3·9 (SE 0·9), P< 0·05) in the control group, whereas normal insulin sensitivity was maintained in the probiotic group (4·4 (SE 0·8) and 4·5 (SE 0·9) before and after overeating, respectively (P>0·05). These results suggest that probiotic supplementation may be useful in the prevention of diet-induced metabolic diseases such as type 2 diabetes.

Effects of soybean oligosaccharides on antioxidant enzyme activities and insulin resistance in pregnant women with gestational diabetes mellitus.

PubMed

Fei, Bei-bei; Ling, Li; Hua, Chen; Ren, Shu-yan

2014-09-01

The effects of soybean oligosaccharides (SBOS) on antioxidant enzyme activities and insulin resistance in pregnant women with gestational diabetes mellitus (GDM) were investigated. Ninety-seven pregnant women with GDM were randomly divided into two groups, the control group (51 cases) and the SBOS group (46 cases). Before the group separation, the blood sugar level in patients was maintained stable by regular diet and insulin treatment. The control group was continued with the insulin treatment, while the SBOS group was treated with the combination of insulin and SBOS. Results showed that SBOS were able to reduce oxidative stress and alleviate insulin resistance in pregnant women with GDM, which indicates that SBOS may play an important role in the control of GDM complications. Copyright © 2014 Elsevier Ltd. All rights reserved.

Cost-Effectiveness Analysis of Insulin Detemir Compared to Neutral Protamine Hagedorn (NPH) in Patients with Type 1 and Type 2 Diabetes Mellitus in Spain.

PubMed

Morales, Cristóbal; de Luis, Daniel; de Arellano, Antonio Ramírez; Ferrario, Maria Giovanna; Lizán, Luis

2015-12-01

An Excel ® (Microsoft Corporation) model was adapted to estimate the short-term (1-year) cost effectiveness of insulin detemir (IDet) versus neutral protamine Hagedorn (NPH) insulin in patients initiating insulin treatment with type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) in Spain. Clinical benefits included the non-severe hypoglycemia rate for T1DM and T2DM, and weight change for T2DM. Three scenarios were included with different hypoglycemia rates estimated on the basis of clinical trials and observational studies. Costs, estimated from perspective of the Spanish Public Healthcare System (Euros 2014), included insulin treatment and non-severe hypoglycemia management costs. Non-severe hypoglycemia, defined as a self-managed event, implied the use of extra glucose testing strips and a general practitioner visit during the week following the event for 25% of patients. An average disutility value was associated to non-severe hypoglycemia events and, for T2DM, to one body mass index unit gain to calculate quality-adjusted life years (QALYs). For the three scenarios a range of 0.025-0.076 QALYs for T1DM and 0.014-0.051 QALYs for T2DM were gained for IDet versus NPH due to non-severe hypoglycemia and weight gain avoidance, in return of an incremental cost of €145-192 for T1DM and €128-206 for T2DM. This resulted in the IDet versus NPH incremental cost-effectiveness ratio (ICER) ranging between €1910/QALY and €7682/QALY for T1DM and €2522/QALY and €15,009/QALY for T2DM. IDet was a cost-effective alternative to NPH insulin in the first year of treatment of patients with T1DM and patients with T2DM in Spain, with ICERs under the threshold value commonly accepted in Spain (€30,000/QALY). Novo Nordisk.

Correlates of basal insulin persistence among insulin-naïve people with type 2 diabetes: results from a multinational survey.

PubMed

Peyrot, Mark; Perez-Nieves, Magaly; Ivanova, Jasmina; Cao, Dachuang; Schmerold, Luke; Kalirai, Samaneh; Hadjiyianni, Irene

2017-10-01

People with T2DM who initiate basal insulin therapy often stop therapy temporarily or permanently soon after initiation. This study analyzes the reasons for and correlates of stopping and restarting basal insulin therapy among people with T2DM. An online survey was completed by 942 insulin-naïve adults with self-reported T2DM from Brazil, France, Germany, Japan, Spain, UK, and US. Respondents had initiated basal insulin therapy within the 3-24 months before survey participation and met criteria for one of three persistence groups: continuers had no gaps of ≥7 days in basal insulin treatment; interrupters had at least one gap in insulin therapy of ≥7 days within the first 6 months after initiation and had since restarted basal insulin; and discontinuers stopped using basal insulin within the first 6 months after initiation and had not restarted. Physician recommendations and cost were strongly implicated in patients stopping and not resuming insulin therapy. Continuous persistence was lower for patients with more worries about insulin initiation, greater difficulties and weight gain while using insulin, and higher for those using pens and perceiving their diabetes as severe. Repeated interruption of insulin therapy was associated with hyperglycemia and treatment burden while using insulin. Resumption and perceived likelihood of resumption were associated with hyperglycemia upon insulin cessation. Perceived likelihood of resumption among discontinuers was associated with perceived benefits of insulin. Better understanding of the risk factors for patient cessation and resumption of basal insulin therapy may help healthcare providers improve persistence with therapy.

Metabolically normal obese people are protected from adverse effects following weight gain

PubMed Central

Fabbrini, Elisa; Yoshino, Jun; Yoshino, Mihoko; Magkos, Faidon; Tiemann Luecking, Courtney; Samovski, Dmitri; Fraterrigo, Gemma; Okunade, Adewole L.; Patterson, Bruce W.; Klein, Samuel

2015-01-01

BACKGROUND. Obesity is associated with insulin resistance and increased intrahepatic triglyceride (IHTG) content, both of which are key risk factors for diabetes and cardiovascular disease. However, a subset of obese people does not develop these metabolic complications. Here, we tested the hypothesis that people defined by IHTG content and insulin sensitivity as “metabolically normal obese” (MNO), but not those defined as “metabolically abnormal obese” (MAO), are protected from the adverse metabolic effects of weight gain. METHODS. Body composition, multiorgan insulin sensitivity, VLDL apolipoprotein B100 (apoB100) kinetics, and global transcriptional profile in adipose tissue were evaluated before and after moderate (~6%) weight gain in MNO (n = 12) and MAO (n = 8) subjects with a mean BMI of 36 ± 4 kg/m2 who were matched for BMI and fat mass. RESULTS. Although the increase in body weight and fat mass was the same in both groups, hepatic, skeletal muscle, and adipose tissue insulin sensitivity deteriorated, and VLDL apoB100 concentrations and secretion rates increased in MAO, but not MNO, subjects. Moreover, biological pathways and genes associated with adipose tissue lipogenesis increased in MNO, but not MAO, subjects. CONCLUSIONS. These data demonstrate that MNO people are resistant, whereas MAO people are predisposed, to the adverse metabolic effects of moderate weight gain and that increased adipose tissue capacity for lipogenesis might help protect MNO people from weight gain–induced metabolic dysfunction. TRIAL REGISTRATION. ClinicalTrials.gov NCT01184170. FUNDING. This work was supported by NIH grants UL1 RR024992 (Clinical Translational Science Award), DK 56341 (Nutrition and Obesity Research Center), DK 37948 and DK 20579 (Diabetes Center Grant), and UL1 TR000450 (KL2 Award); a Central Society for Clinical and Translational Research Early Career Development Award; and by grants from the Longer Life Foundation and the Kilo Foundation. PMID:25555214

Lipid metabolism and body composition in Gclm(-/-) mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kendig, Eric L.; Center for Environmental Genetics, University of Cincinnati Medical Center, P.O. Box 670056, Cincinnati, OH 45267; Chen, Ying

2011-12-15

In humans and experimental animals, high fat diets (HFD) are associated with risk factors for metabolic diseases, such as excessive weight gain and adiposity, insulin resistance and fatty liver. Mice lacking the glutamate-cysteine ligase modifier subunit gene (Gclm(-/-)) and deficient in glutathione (GSH), are resistant to HFD-mediated weight gain. Herein, we evaluated Gclm-associated regulation of energy metabolism, oxidative stress, and glucose and lipid homeostasis. C57BL/6J Gclm(-/-) mice and littermate wild-type (WT) controls received a normal diet or an HFD for 11 weeks. HFD-fed Gclm(-/-) mice did not display a decreased respiratory quotient, suggesting that they are unable to process lipidmore » for metabolism. Although dietary energy consumption and intestinal lipid absorption were unchanged in Gclm(-/-) mice, feeding these mice an HFD did not produce excess body weight nor fat storage. Gclm(-/-) mice displayed higher basal metabolic rates resulting from higher activities of liver mitochondrial NADH-CoQ oxidoreductase, thus elevating respiration. Although Gclm(-/-) mice exhibited strong systemic and hepatic oxidative stress responses, HFD did not promote glucose intolerance or insulin resistance. Furthermore, HFD-fed Gclm(-/-) mice did not develop fatty liver, likely resulting from very low expression levels of genes encoding lipid metabolizing enzymes. We conclude that Gclm is involved in the regulation of basal metabolic rate and the metabolism of dietary lipid. Although Gclm(-/-) mice display a strong oxidative stress response, they are protected from HFD-induced excessive weight gain and adipose deposition, insulin resistance and steatosis. -- Highlights: Black-Right-Pointing-Pointer A high fat diet does not produce body weight and fat gain in Gclm(-/-) mice. Black-Right-Pointing-Pointer A high fat diet does not induce steatosis or insulin resistance in Gclm(-/-) mice. Black-Right-Pointing-Pointer Gclm(-/-) mice have high basal metabolism and mitochondrial oxygen consumption. Black-Right-Pointing-Pointer Expression of lipid metabolizing genes is extremely low in Gclm(-/-) mice.« less

Comparative efficacy and safety of oral antidiabetic drugs and insulin in treating gestational diabetes mellitus

PubMed Central

Liang, Hui-ling; Ma, Shu-juan; Xiao, Yan-ni; Tan, Hong-zhuan

2017-01-01

Abstract Background: The safety and efficacy of different drugs in treatment of gestational diabetes mellitus (GDM) patients who could not maintain normal glucose level only through diet and exercise remains to be debated. We performed this network meta-analysis (NAM) to compare and rank different antidiabetic drugs in glucose level control and pregnancy outcomes in GDM patients. Methods: We searched PubMed, Cochrane Library, Web of Science, and Embase up to December 31, 2016. Randomized controlled trials (RCTs) related to different drugs in the treatment of GDM patients were enrolled. We extracted the relevant information and assessed the risk of bias with the Cochrane risk of bias tool. We did pair-wise meta-analyses using the fixed-effects model or random-effects model and then adopted random-effects NAM combining both direct and indirect evidence within a Bayesian framework, to calculate the odds ratio (OR) or standardized mean difference (SMD) and to draw a surface under the cumulative ranking curve of the neonatal and maternal outcomes of different treatments in GDM patients. Results: Thirty-two randomized controlled trials (RCTs) were included in this NAM, including 6 kinds of treatments (metformin, metformin plus insulin, insulin, glyburide, acarbose, and placebo). The results of the NAM showed that regarding the incidence of macrosomia and LGA, metformin had lower incidence than glyburide (OR, 0.5411 and 0.4177). In terms of the incidence of admission to the NICU, insulin had higher incidence compared with glyburide (OR, 1.844). As for the incidence of neonatal hypoglycemia, metformin had lower incidence than insulin and glyburide (OR, 0.6331 and 0.3898), and insulin was lower than glyburide (OR, 0.6236). For mean birth weight, metformin plus insulin was lower than insulin (SMD, -0.5806), glyburide (SMD, -0.7388), and placebo (SMD, -0.6649). Besides, metformin was observed to have lower birth weight than glyburide (SMD, 0.2591). As for weight gain, metformin and metformin plus insulin were lower than insulin (SMD, -0.9166, -1.53). Ranking results showed that glyburide might be the optimum treatment regarding average glucose control, and metformin is the fastest in glucose control for GDM patients; glyburide have the highest incidence of macrosomia, preeclampsia, hyperbilirubinemia, neonatal hypoglycemia, shortest gestational age at delivery, and lowest mean birth weight; metformin (plus insulin when required) have the lowest incidence of macrosomia, PIH, LGA, RDS, low gestational age at delivery, and low birth weight. Besides, insulin had the highest incidence of NICU admission, acarbose had the lowest risk of neonatal hypoglycemia. Conclusion: Our study concluded that metformin is fastest in glucose control, with a more favorable pregnancy outcomes—would be a better option, but its rate of glucose control is the lowest.However, glyburide is the optimumtreatment regarding the rate of glucose control, but withmore adverse outcomes. This NAMbased on 32 RCTs will strongly help to guide further development of management for GDM patients, clinicians should carefully balance the risk–benefit profile of different treatments according to various situations. PMID:28930827

Periodic-Zone Model Predictive Control for Diurnal Closed-Loop Operation of an Artificial Pancreas

PubMed Central

Gondhalekar, Ravi; Dassau, Eyal; Zisser, Howard C.; Doyle, Francis J.

2013-01-01

Background The objective of this research is an artificial pancreas (AP) that performs automatic regulation of blood glucose levels in people with type 1 diabetes mellitus. This article describes a control strategy that performs algorithmic insulin dosing for maintaining safe blood glucose levels over prolonged, overnight periods of time and furthermore was designed with outpatient, multiday deployment in mind. Of particular concern is the prevention of nocturnal hypoglycemia, because during sleep, subjects cannot monitor themselves and may not respond to alarms. An AP intended for prolonged and unsupervised outpatient deployment must strategically reduce the risk of hypoglycemia during times of sleep, without requiring user interaction. Methods A diurnal insulin delivery strategy based on predictive control methods is proposed. The so-called “periodic-zone model predictive control” (PZMPC) strategy employs periodically time-dependent blood glucose output target zones and furthermore enforces periodically time-dependent insulin input constraints to modulate its behavior based on the time of day. Results The proposed strategy was evaluated through an extensive simulation-based study and a preliminary clinical trial. Results indicate that the proposed method delivers insulin more conservatively during nighttime than during daytime while maintaining safe blood glucose levels at all times. In clinical trials, the proposed strategy delivered 77% of the amount of insulin delivered by a time-invariant control strategy; specifically, it delivered on average 1.23 U below, compared with 0.31 U above, the nominal basal rate overnight while maintaining comparable, and safe, blood glucose values. Conclusions The proposed PZMPC algorithm strategically prevents nocturnal hypoglycemia and is considered a significant step toward deploying APs into outpatient environments for extended periods of time in full closed-loop operation. PMID:24351171

Central insulin-mediated regulation of hepatic glucose production [Review].

PubMed

Inoue, Hiroshi

2016-01-01

Insulin controls hepatic glucose production (HGP) and maintains glucose homeostasis through the direct action of hepatic insulin receptors, as well as the indirect action of insulin receptors in the central nervous system. Insulin acts on insulin receptors in the hypothalamic arcuate nucleus, activates ATP-sensitive potassium channels in a phosphoinositide 3-kinase (PI3K)-dependent manner, induces hyperpolarization of the hypothalamic neurons, and regulates HGP via the vagus nerve. In the liver, central insulin action augments IL-6 expression in Kupffer cells and activates STAT3 transcription factors in hepatocytes. Activated STAT3 suppresses the gene expression of gluconeogenic enzymes, thereby reducing HGP. It has become evident that nutrients such as glucose, fatty acids, and amino acids act upon the hypothalamus together with insulin, affecting HGP. On the other hand, HGP control by central insulin action is impeded in obesity and impeded by insulin resistance due to disturbance of PI3K signaling and inflammation in the hypothalamus or inhibition of STAT3 signaling in the liver. Although the mechanism of control of hepatic gluconeogenic gene expression by central insulin action is conserved across species, its importance in human glucose metabolism has not been made entirely clear and its elucidation is anticipated in the future.

Glibenclamide, metformin, and insulin for the treatment of gestational diabetes: a systematic review and meta-analysis

PubMed Central

Balsells, Montserrat; García-Patterson, Apolonia; Solà, Ivan; Roqué, Marta; Gich, Ignasi

2015-01-01

Objective To summarize short term outcomes in randomized controlled trials comparing glibenclamide or metformin versus insulin or versus each other in women with gestational diabetes requiring drug treatment. Design Systematic review and meta-analysis. Eligibility criteria for selecting studies Randomized controlled trials that fulfilled all the following: (1) published as full text; (2) addressed women with gestational diabetes requiring drug treatment; (3) compared glibenclamide v insulin, metformin v insulin, or metformin v glibenclamide; and (4) provided information on maternal or fetal outcomes. Data sources Medline, CENTRAL, and Embase were searched up to 20 May 2014. Outcomes measures We considered 14 primary outcomes (6 maternal, 8 fetal) and 16 secondary (5 maternal, 11 fetal) outcomes. Results We analyzed 15 articles, including 2509 subjects. Significant differences for primary outcomes in glibenclamide v insulin were obtained in birth weight (mean difference 109 g (95% confidence interval 35.9 to 181)), macrosomia (risk ratio 2.62 (1.35 to 5.08)), and neonatal hypoglycaemia (risk ratio 2.04 (1.30 to 3.20)). In metformin v insulin, significance was reached for maternal weight gain (mean difference −1.14 kg (−2.22 to −0.06)), gestational age at delivery (mean difference −0.16 weeks (−0.30 to −0.02)), and preterm birth (risk ratio 1.50 (1.04 to 2.16)), with a trend for neonatal hypoglycaemia (risk ratio 0.78 (0.60 to 1.01)). In metformin v glibenclamide, significance was reached for maternal weight gain (mean difference −2.06 kg (−3.98 to −0.14)), birth weight (mean difference −209 g (−314 to −104)), macrosomia (risk ratio 0.33 (0.13 to 0.81)), and large for gestational age newborn (risk ratio 0.44 (0.21 to 0.92)). Four secondary outcomes were better for metformin in metformin v insulin, and one was worse for metformin in metformin v glibenclamide. Treatment failure was higher with metformin than with glibenclamide. Conclusions At short term, in women with gestational diabetes requiring drug treatment, glibenclamide is clearly inferior to both insulin and metformin, while metformin (plus insulin when required) performs slightly better than insulin. According to these results, glibenclamide should not be used for the treatment of women with gestational diabetes if insulin or metformin is available. Systematic review registration NCT01998113 PMID:25609400

Liver-specific expression of carboxylesterase 1g/esterase-x reduces hepatic steatosis, counteracts dyslipidemia and improves insulin signaling.

PubMed

Bahitham, Wesam; Watts, Russell; Nelson, Randal; Lian, Jihong; Lehner, Richard

2016-05-01

Ces1g/Es-x deficiency in mice results in weight gain, insulin resistance, fatty liver and hyperlipidemia through upregulation of de novo lipogenesis and oversecretion of triacylglycerol (TG)-rich lipoproteins. Here, we show that restoration of Ces1g/Es-x expression only in the liver significantly reduced hepatic TG concentration accompanied by decreased size of lipid droplets, reduced secretion of very low-density lipoproteins and improved insulin-mediated signal transduction in the liver. Collectively, these results demonstrate that hepatic Ces1g/Es-x plays a critical role in limiting hepatic steatosis, very low-density lipoprotein assembly and in augmenting insulin sensitivity. Copyright © 2016 Elsevier B.V. All rights reserved.

Systemic absorption of insulin and glucagon applied topically to the eyes of rats and a diabetic dog.

PubMed

Pillion, D J; Wang, P; Yorks, J; McCann, P; Meezan, E

1995-01-01

Nondiabetic rats were anesthetized with xylazine/ketamine to induce hyperglycemia and systemic insulin absorption from eyedrops formulated with dodecylmaltoside was quantitated by both a decrease in serum levels of D-glucose and an increase in immunoreactive insulin levels. When insulin eyedrop administration was delayed until 60 minutes after the administration of eyedrops containing 0.25% dodecylmaltoside, the enhanced systemic absorption of insulin was maintained, suggesting that dodecylmaltoside had an effect directly on the permeability of the nasal sinus epithelium. When glucagon was formulated in eyedrops or nosedrops containing dodecylmaltoside, systemic absorption of glucagon could be measured in the form of an increase in the serum D-glucose concentration following nasal application, but not after ocular application. Eyedrops containing insulin plus 0.125% dodecylmaltoside were administered to a diabetic dog; a dose of 20 units of regular insulin caused a modest decrease in serum D-glucose concentration and a concomitant increase in serum immunoreactive insulin content. These results provide evidence that peptide drugs such as insulin can be formulated in eyedrops with low concentrations of dodecylmaltoside, a mild nonionic surfactant.

Maintaining vigorous activity attenuates 7-yr weight gain in 8340 runners.

PubMed

Williams, Paul T

2007-05-01

Body weight generally increases with aging in Western societies. Although training studies show that exercise produces acute weight loss, it is unclear whether the long-term maintenance of vigorous exercise attenuates the trajectory of age-related weight gain. Specifically, prior studies have not tested whether the maintenance of physical activity, in the absence of any change in activity, prevents weight gain. Prospective study of 6119 male and 2221 female runners whose running distances changed < 5 km x wk(-1) between baseline and follow-up surveys 7 yr later. On average, men who maintained modest (0-23 km x wk(-1)), intermediate (24-47 km x wk(-1)), or prolonged running distances (> or = 48 km x wk(-1)) all gained weight through age 64; however, those who maintained > or = 48 km x wk(-1) had one half the average annual weight gain of those who maintained < 24 km x wk(-1). For example, between the ages of 35 and 44 in men and 30 and 39 yr in women, those who maintained < 24 km x wk(-1) gained, on average, 2.1 and 2.9 kg more per decade than those averaging > 48 km x wk(-1). Age-related weight gain, and its attenuation by maintained exercise, were both greater in younger than in older men. Men's gains in waist circumference with age, and its attenuation by maintaining running, were the same in older and younger men. Regardless of age, women increased their body weight, waist circumference, and hip circumference over time, and these measurements were attenuated in proportion to their maintained running distance. In both sexes, running disproportionately prevented more extreme increases in weight. As they aged, men and women gained less weight in proportion to their levels of sustained vigorous activity. This long-term beneficial effect is in addition to the acute weight loss that occurs with increased activity.

Insulin Resistance Induced by Hyperinsulinemia Coincides with a Persistent Alteration at the Insulin Receptor Tyrosine Kinase Domain

PubMed Central

Catalano, Karyn J.; Maddux, Betty A.; Szary, Jaroslaw; Youngren, Jack F.; Goldfine, Ira D.; Schaufele, Fred

2014-01-01

Insulin resistance, the diminished response of target tissues to insulin, is associated with the metabolic syndrome and a predisposition towards diabetes in a growing proportion of the worldwide population. Under insulin resistant states, the cellular response of the insulin signaling pathway is diminished and the body typically responds by increasing serum insulin concentrations to maintain insulin signaling. Some evidence indicates that the increased insulin concentration may itself further dampen insulin response. If so, insulin resistance would worsen as the level of circulating insulin increases during compensation, which could contribute to the transition of insulin resistance to more severe disease. Here, we investigated the consequences of excess insulin exposure to insulin receptor (IR) activity. Cells chronically exposed to insulin show a diminished the level of IR tyrosine and serine autophosphorylation below that observed after short-term insulin exposure. The diminished IR response did not originate with IR internalization since IR amounts at the cell membrane were similar after short- and long-term insulin incubation. Förster resonance energy transfer between fluorophores attached to the IR tyrosine kinase (TK) domain showed that a change in the TK domain occurred upon prolonged, but not short-term, insulin exposure. Even though the altered ‘insulin refractory’ IR TK FRET and IR autophosphorylation levels returned to baseline (non-stimulated) levels after wash-out of the original insulin stimulus, subsequent short-term exposure to insulin caused immediate re-establishment of the insulin-refractory levels. This suggests that some cell-based ‘memory’ of chronic hyperinsulinemic exposure acts directly at the IR. An improved understanding of that memory may help define interventions to reset the IR to full insulin responsiveness and impede the progression of insulin resistance to more severe disease states. PMID:25259572

A decade of temporal trends in overweight/obesity in youth with type 1 diabetes after the Diabetes Control and Complications Trial.

PubMed

Baskaran, Charumathi; Volkening, Lisa K; Diaz, Monica; Laffel, Lori M

2015-06-01

Youth with type 1 diabetes (T1D) are at risk for weight gain due to the epidemic of childhood overweight/obesity and common use of intensive insulin therapy; the latter resulted in weight gain in the Diabetes Control and Complications Trial. To assess overweight/obesity prevalence and intensive insulin therapy use in youth with T1D over a decade and identify factors associated with weight status and glycemic control. We obtained cross-sectional data from four unique cohorts (1999, 2002, 2006, and 2009). Youth (N = 507, 49% male) were 8-16 yr old with T1D duration ≥6 months, A1c 6.0-12.0% (42-108 mmol/mol), and daily insulin dose ≥0.5 U/kg. Across cohorts, age, body mass index (BMI) percentile, and A1c ranged from 12.0 ± 2.2 to 12.8 ± 2.3 yr, 70 ± 22 to 72 ± 21, and 8.3 ± 1.0 (67 ± 11) to 8.5 ± 1.1% (69 ± 12 mmol/mol), respectively. Intensive insulin therapy use increased from 52 to 97% (p < 0.001) between 1999 and 2009. However, prevalence of overweight/obesity remained similar, 27% (1999), 36% (2002), 33% (2006), and 31% (2009) (p = 0.54), as did z-BMI. In multivariate analysis, higher A1c was related to higher insulin dose (p < 0.01), less frequent blood glucose monitoring (p < 0.001), and non-white race (p < 0.001); A1c was not related to z-BMI, intensive insulin therapy, or cohort. z-BMI was related to insulin dose (p < 0.005) but not intensive insulin therapy or cohort. Despite near-universal implementation of intensive insulin therapy, overweight/obesity prevalence in youth with T1D remained stable over a decade, similar to the general pediatric population. However, A1c remained suboptimal, underscoring the need to optimize T1D treatment to reduce future complication risk. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Insulin glargine 300 units/mL: a guide for healthcare professionals involved in the management of diabetes.

PubMed

Strong, Jodi; Kruger, Davida; Novak, Lucia

2017-04-01

Insulin glargine 300 units/mL: Insulin glargine 300 units/mL (Gla-300) is a formulation of insulin glargine that delivers the same number of insulin units in one-third of the injectable volume of insulin glargine 100 units/mL (Gla-100). Glucose control: Recently approved in the United States and in Europe for use in type 1 and type 2 diabetes, Gla-300 has a more constant and evenly distributed glucose-lowering effect compared with Gla-100, with a duration of action beyond 24 hours and lower within-day and between-day intra-individual variability in blood glucose levels. These benefits translate into predictable and sustained glucose control from a once-daily injection, with potential for fewer hypoglycemia episodes and less weight gain. Case studies are presented to highlight the potential clinical benefits and considerations associated with initiating treatment with Gla-300 in people with type 1 and type 2 diabetes.

Disorders of carbohydrate or lipid metabolism in camelids.

PubMed

Cebra, Christopher K

2009-07-01

Camelids develop a number of disturbances related to energy metabolism. Some are similar to disorders seen in other species, but most relate to camelids' unusual characteristics of poor glucose tolerance, partial insulin resistance, and low concentrations of circulating insulin. Camelids are especially prone to abnormalities related to stimuli that inhibit insulin release or activity, or that promote activities normally antagonized by insulin. These include stimuli that mobilize glycogen or fat stores, or inhibit glucose uptake or intravascular glycolysis. These stimuli are generally more important than negative energy balance in triggering these disorders. Treatment must concentrate on the hormonal aspects, and not just provision of energy. Treatments related to hormonal aspects include those to decrease catecholamine release and to provide exogenous insulin until the camelid is again able to maintain appropriate energy substrate homeostasis.

Effect of hypothyroidism on insulin sensitivity and glucose tolerance in dogs.

PubMed

Hofer-Inteeworn, Natalie; Panciera, David L; Monroe, William E; Saker, Korinn E; Davies, Rebecca Hegstad; Refsal, Kent R; Kemnitz, Joseph W

2012-04-01

To determine the effects of hypothyroidism on insulin sensitivity, glucose tolerance, and concentrations of hormones counter-regulatory to insulin in dogs. 8 anestrous mixed-breed bitches with experimentally induced hypothyroidism and 8 euthyroid control dogs. The insulin-modified frequently sampled IV glucose tolerance test and minimal model analysis were used to determine basal plasma insulin and glucose concentrations, acute insulin response to glucose, insulin sensitivity, glucose effectiveness, and disposition index. Growth hormone response was assessed by stimulation and suppression tests. Additionally, basal serum growth hormone (GH) and insulin-like growth factor-1 (IGF-1) concentrations and urine cortisol-to-creatinine concentration ratios were measured and dual energy x-ray absorptiometry was performed to evaluate body composition. Insulin sensitivity was lower in the hypothyroid group than in the euthyroid group, whereas acute insulin response to glucose was higher. Glucose effectiveness and disposition index were not different between groups. Basal serum GH and IGF-1 concentrations as well as abdominal fat content were high in hypothyroid dogs, but urine cortisol-to-creatinine concentration ratios were unchanged. Hypothyroidism appeared to negatively affect glucose homeostasis by inducing insulin resistance, but overall glucose tolerance was maintained by increased insulin secretion in hypothyroid dogs. Possible factors affecting insulin sensitivity are high serum GH and IGF-1 concentrations and an increase in abdominal fat. In dogs with diseases involving impaired insulin secretion such as diabetes mellitus, concurrent hypothyroidism can have important clinical implications.

Insulin Glargine 300 U/mL: A Review in Diabetes Mellitus.

PubMed

Blair, Hannah A; Keating, Gillian M

2016-03-01

Insulin glargine 300 U/mL (Toujeo(®)) is a long-acting basal insulin analogue approved for the treatment of diabetes mellitus. Insulin glargine 300 U/mL has a more stable and prolonged pharmacokinetic/pharmacodynamic profile than insulin glargine 100 U/mL (Lantus(®)), with a duration of glucose-lowering activity exceeding 24 h. In several 6-month phase III trials, insulin glargine 300 U/mL achieved comparable glycaemic control to that seen with insulin glargine 100 U/mL in patients with type 1 or type 2 diabetes, albeit with consistently higher daily basal insulin requirements. These improvements in glycaemic control were maintained during longer-term (12 months) treatment. Insulin glargine 300 U/mL was generally associated with a lower risk of nocturnal hypoglycaemia than insulin glargine 100 U/mL in insulin-experienced patients with type 2 diabetes, while the risk of nocturnal hypoglycaemia did not significantly differ between treatment groups in insulin-naïve patients with type 2 diabetes or in patients with type 1 diabetes. To conclude, once-daily subcutaneous insulin glargine 300 U/mL is an effective and generally well tolerated basal insulin therapy option for patients with type 1 or type 2 diabetes.

New Basal Insulins: a Clinical Perspective of Their Use in the Treatment of Type 2 Diabetes and Novel Treatment Options Beyond Basal Insulin.

PubMed

Frias, Patrick F; Frias, Juan Pablo

2017-08-18

The purpose of this review was to review advances in basal insulin formulations and new treatment options for patients with type 2 diabetes not achieving glycemic targets despite optimized basal insulin therapy. Advances in basal insulin formulations have resulted in products with increasingly favorable pharmacokinetic and pharmacodynamic properties, including flatter, peakless action profiles, less inter- and intra-patient variability, and longer duration of activity. These properties have translated to significantly reduced risk of hypoglycemia (particularly during the night) compared with previous generation basal insulins. When optimized basal insulin therapy is not sufficient to obtain or maintain glycemic goals, various options exist to improve glycemic control, including intensification of insulin therapy with the addition of prandial insulin or changing to pre-mixed insulin and, more recently, the addition of a GLP-1 receptor agonist, either as a separate injection or as a component of one of the new fixed-ratio combinations of a basal insulin and GLP-1 RA. New safer and often more convenient basal insulins and fixed ratio combinations containing basal insulin (and GLP-1 receptor agonist) are available today for patients with type 2 diabetes not achieving glycemic goals. Head-to-head studies comparing the latest generation basal insulins are underway, and future studies assessing the fixed-ratio combinations will be important to better understand their differentiating features.

Insulin binding and glucose uptake of adipocytes in rats adapted to hypergravitational force

NASA Technical Reports Server (NTRS)

Kobayashi, M.; Mondon, C. E.; Oyama, J.

1980-01-01

Rats were exposed to 4.15 g for 1 yr and weight and age matched, and lean noncentrifuged rats were used as control groups. Rats exposed to chronic hypergravity (hypergravic rats) were found to show lower ambient insulin levels, greater food intake with smaller body weight gain, and decreased size of isolated adipocytes. The ability of adipocytes from the hypergravic rats to bind insulin was increased. With Scatchard analysis, both number and affinity of receptors were increased. In contrast to the increased binding, glucose transport was found to be decreased in adipocytes from these animals. However, when the data were expressed as a percentage of maximal effect, the half maximal insulin effect for both the hypergravic and lean control groups was produced at an insulin concentration of 0.23 + or - 0.02 ng/ml, which was lower than the insulin concentration of 0.31 + or - 0.02 ng/ml for the weight-matched control group (P less than 0.05). This increased insulin sensitivity in the hypergravic group was accounted for by an increased number of receptors.

Therapeutics in pediatric diabetes: insulin and non-insulin approaches. Part of a series on Pediatric Pharmacology, guest edited by Gianvincenzo Zuccotti, Emilio Clementi, and Massimo Molteni.

PubMed

Kim, Jongoh; Kim, Se Min; Nguyen, Ha Cam Thuy; Redondo, Maria Jose

2012-01-01

Treatment of pediatric diabetes can be challenging. Strict glucose control can be accompanied by hypoglycemia and weight gain. Recently, there have been many developments in insulin preparations and delivery methods which make insulin levels more close to a physiologic pattern. Newly developed rapid/long acting analogues and delivery devices such as continuous subcutaneous insulin infusion (CSII, insulin pump) may reduce hypoglycemia and improve glycemic control. CSII combined with continuous glucose monitoring can achieve even better glycemic control. The closed-loop system is rapidly evolving and an artificial pancreas will be available in the near future. It is now recognized that several hormones other than insulin such as glucagon, amylin, and incretins contribute to glucose homeostasis. The role of co-adjuncts such as metformin, amylin analogues, and incretin based therapy is now emerging. Immunotherapy in a high risk population or patients in the early phase of type 1 diabetes may prevent further destruction of pancreatic β cells. Copyright © 2011 Elsevier Ltd. All rights reserved.

Butyrylcholinesterase regulates central ghrelin signaling and has an impact on food intake and glucose homeostasis.

PubMed

Chen, V P; Gao, Y; Geng, L; Brimijoin, S

2017-09-01

Ghrelin is the only orexigenic hormone known to stimulate food intake and promote obesity and insulin resistance. We recently showed that plasma ghrelin is controlled by butyrylcholinesterase (BChE), which has a strong impact on feeding and weight gain. BChE knockout (KO) mice are prone to obesity on high-fat diet, but hepatic BChE gene transfer rescues normal food intake and obesity resistance. However, these mice lack brain BChE and still develop hyperinsulinemia and insulin resistance, suggesting essential interactions between BChE and ghrelin within the brain. To test the hypothesis we used four experimental groups: (1) untreated wild-type mice, (2) BChE KO mice with LUC delivered by adeno-associated virus (AAV) in combined intravenous (i.v.) and intracerebral (i.c.) injections, (3) KO mice given AAV for mouse BChE (i.v. only) and (4) KO mice given the same vector both i.v. and i.c. All mice ate a 45% calorie high-fat diet from the age of 1 month. Body weight, body composition, daily caloric intake and serum parameters were monitored throughout, and glucose tolerance and insulin tolerance tests were performed at intervals. Circulating ghrelin levels dropped substantially in the KO mice after i.v. AAV-BChE delivery, which led to normal food intake and healthy body weight. BChE KO mice that received AAV-BChE through i.v. and i.c. combined treatments not only resisted weight gain on high-fat diet but also retained normal glucose and insulin tolerance. These data indicate a central role for BChE in regulating both insulin and glucose homeostasis. BChE gene transfer could be a useful therapy for complications linked to diet-induced obesity and insulin resistance.

Effect of Intermittent Hypoxia and Rimonabant on Glucose Metabolism in Rats: Involvement of Expression of GLUT4 in Skeletal Muscle

PubMed Central

Wang, Xiaoya; Yu, Qin; Yue, Hongmei; Zeng, Shuang; Cui, Fenfen

2015-01-01

Background Obstructive sleep apnea (OSA) and its main feature, chronic intermittent hypoxia (IH) during sleep, is closely associated with insulin resistance (IR) and diabetes. Rimonabant can regulate glucose metabolism and improve IR. The present study aimed to assess the effect of IH and rimonabant on glucose metabolism and insulin sensitivity, and to explore the possible mechanisms. Material/Methods Thirty-two rats were randomly assigned into 4 groups: Control group, subjected to intermittent air only; IH group, subjected to IH only; IH+NS group, subjected to IH and treated with normal saline; and IH+Rim group, subjected to IH and treated with 10 mg/kg/day of rimonabant. All rats were killed after 28 days of exposure. Then, the blood and skeletal muscle were collected. We measured fasting blood glucose levels, fasting blood insulin levels, and the expression of glucose transporter 4 (GLUT4) in both mRNA and protein levels in skeletal muscle. Results IH can slow weight gain, increase serum insulin level, and reduce insulin sensitivity in rats. The expressions of GLUT4 mRNA, total GLUT4, and plasma membrane protein of GLUT4 (PM GLUT4) in skeletal muscle were decreased. Rimonabant treatment was demonstrated to improve weight gain and insulin sensitivity of the rats induced by IH. Rimonabant significantly upregulated the expression of GLUT4 mRNA, PM GLUT4, and total GLUT4 in skeletal muscle. Conclusions The present study demonstrates that IH can cause IR and reduced expression of GLUT4 in both mRNA and protein levels in skeletal muscle of rats. Rimonabant treatment can improve IH – induced IR, and the upregulation of GLUT4 expression may be involved in this process. PMID:26503060

Aging Impairs Myocardial Fatty Acid and Ketone Oxidation and Modifies Cardiac Functional and Metabolic Responses to Insulin in Mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hyyti, Outi M.; Ledee, Dolena; Ning, Xue-Han

2010-07-02

Aging presumably initiates shifts in substrate oxidation mediated in part by changes in insulin sensitivity. Similar shifts occur with cardiac hypertrophy and may contribute to contractile dysfunction. We tested the hypothesis that aging modifies substrate utilization and alters insulin sensitivity in mouse heart when provided multiple substrates. In vivo cardiac function was measured with microtipped pressure transducers in the left ventricle from control (4–6 mo) and aged (22–24 mo) mice. Cardiac function was also measured in isolated working hearts along with substrate and anaplerotic fractional contributions to the citric acid cycle (CAC) by using perfusate containing 13C-labeled free fatty acidsmore » (FFA), acetoacetate, lactate, and unlabeled glucose. Stroke volume and cardiac output were diminished in aged mice in vivo, but pressure development was preserved. Systolic and diastolic functions were maintained in aged isolated hearts. Insulin prompted an increase in systolic function in aged hearts, resulting in an increase in cardiac efficiency. FFA and ketone flux were present but were markedly impaired in aged hearts. These changes in myocardial substrate utilization corresponded to alterations in circulating lipids, thyroid hormone, and reductions in protein expression for peroxisome proliferator-activated receptor (PPAR)α and pyruvate dehydrogenase kinase (PDK)4. Insulin further suppressed FFA oxidation in the aged. Insulin stimulation of anaplerosis in control hearts was absent in the aged. The aged heart shows metabolic plasticity by accessing multiple substrates to maintain function. However, fatty acid oxidation capacity is limited. Impaired insulin-stimulated anaplerosis may contribute to elevated cardiac efficiency, but may also limit response to acute stress through depletion of CAC intermediates.« less

O-Linked-N-Acetylglucosamine Cycling and Insulin Signaling Are Required for the Glucose Stress Response in Caenorhabditis elegans

PubMed Central

Mondoux, Michelle A.; Love, Dona C.; Ghosh, Salil K.; Fukushige, Tetsunari; Bond, Michelle; Weerasinghe, Gayani R.; Hanover, John A.; Krause, Michael W.

2011-01-01

In a variety of organisms, including worms, flies, and mammals, glucose homeostasis is maintained by insulin-like signaling in a robust network of opposing and complementary signaling pathways. The hexosamine signaling pathway, terminating in O-linked-N-acetylglucosamine (O-GlcNAc) cycling, is a key sensor of nutrient status and has been genetically linked to the regulation of insulin signaling in Caenorhabditis elegans. Here we demonstrate that O-GlcNAc cycling and insulin signaling are both essential components of the C. elegans response to glucose stress. A number of insulin-dependent processes were found to be sensitive to glucose stress, including fertility, reproductive timing, and dauer formation, yet each of these differed in their threshold of sensitivity to glucose excess. Our findings suggest that O-GlcNAc cycling and insulin signaling are both required for a robust and adaptable response to glucose stress, but these two pathways show complex and interdependent roles in the maintenance of glucose–insulin homeostasis. PMID:21441213

Fasting glucose and postprandial glycemia: which is the best target for improving outcomes? The Apollo and 4-T Trials.

PubMed

Monnier, Louis; Colette, Claude

2008-11-01

Two studies, the Apollo and 4-T Trials, were conducted in order to determine which insulin regimen (basal or prandial) is the most efficient for the treatment of insulin-requiring type 2 diabetic patients. Both trials compared treatments using prandial insulins (aspart or lispro) three times daily with more classical insulin strategies using basal insulin given once daily (glargine or detemir) or twice daily if required (detemir in the 4-T Study). Both studies showed that a therapeutic regimen involving prandial insulin resulted in equal (Apollo Study) or greater (4-T Study) reductions in patients' HbA(1c) levels than basal insulin regimens. However, the prandial insulin strategies were accompanied by higher risks of hypoglycemia and greater weight gain. As a consequence, the investigators of the two studies concluded that basal insulin once daily provides a simple and effective option with less adverse effects than prandial insulin three times a day. Such conclusions are certainly important for guiding strategies in the vast majority of type 2 diabetic patients who require an add-on insulin therapy. However, the authors' opinion is that the choice between either basal or prandial insulin alone and combined insulin regimens with basal and prandial insulin should be tailored according to the patient's clinical status by paying more attention to the respective contributions of basal and prandial hyperglycemia to their overall hyperglycemia. This recommendation seems to be particularly important when insulin treatment is initiated in patients exhibiting HbA(1c) levels between 7.0 and 8.0%.

Insulin in the Brain: There and Back Again

PubMed Central

Banks, William A.; Owen, Joshua B.; Erickson, Michelle A

2012-01-01

Insulin performs unique functions within the CNS. Produced nearly exclusively by the pancreas, insulin crosses the blood-brain barrier (BBB) using a saturable transporter, affecting feeding and cognition through CNS mechanisms largely independent of glucose utilization. Whereas peripheral insulin acts primarily as a metabolic regulatory hormone, CNS insulin has an array of effects on brain that may more closely resemble the actions of the ancestral insulin molecule. Brain endothelial cells (BEC), the cells that form the vascular BBB and contain the transporter that translocates insulin from blood to brain, is itself regulated by insulin. The insulin transporter is altered by physiological and pathological factors including hyperglycemia and the diabetic state. The latter can lead to BBB disruption. Pericytes, pluripotent cells in intimate contact with the BEC, protect the integrity of the BBB and its ability to transport insulin. Most of insulin’s known actions within the CNS are mediated through two canonical pathways, the phosphoinositide-3 kinase (PI3)/Akt and Ras/mitogen activated kinase (MAPK) cascades. Resistance to insulin action within the CNS, sometimes referred to as diabetes mellitus type III, is associated with peripheral insulin resistance, but it is possible that variable hormonal resistance syndromes exist so that resistance at one tissue bed may be independent of that at others. CNS insulin resistance is associated with Alzheimer’s disease, depression, and impaired baroreceptor gain in pregnancy. These aspects of CNS insulin action and the control of its entry by the BBB are likely only a small part of the story of insulin within the brain. PMID:22820012

Bioavailable Insulin-Like Growth Factor-I Inversely Related to Weight Gain in Postmenopausal Women regardless of Exogenous Estrogen

PubMed Central

Jung, Su Yon; Hursting, Stephen D.; Guindani, Michele; Vitolins, Mara Z.; Paskett, Electra; Chang, Shine

2014-01-01

Background Weight gain, insulin-like growth factor-I (IGF-I) levels, and excess exogenous steroid hormone use are putative cancer risk factors, yet their interconnected pathways have not been fully characterized. This cross-sectional study investigated the relationship between plasma IGF-I levels and weight gain according to body mass index (BMI), leptin levels, and exogenous estrogen use among postmenopausal women. Methods This study included 794 postmenopausal women who enrolled in an ancillary study of the Women's Health Initiative Observational Study between February 1995 and July 1998. The relationship between IGF-I levels and weight gain was analyzed using ordinal logistic regression. We used the molar ratio of IGF-I to IGF binding protein-3 (IGF-I/IGFBP-3) or circulating IGF-I levels adjusting for IGFBP-3 as a proxy of bioavailable IGF-I. The plasma concentrations were expressed as quartiles. Results Among the obese group, women in the third quartile (Q3) of IGF-I and highest quartile of IGF-I/IGFBP-3 were less likely to gain weight (>3% from baseline) than were women in the first quartiles (Q1). Among the normal weight group, women in Q2 and Q3 of IGF-I/IGFBP-3 were 70% less likely than those in Q1 to gain weight. Among current estrogen users, Q3 of IGF-I/IGFBP-3 had 0.5 times the odds of gaining weight than Q1. Conclusions Bioavailable IGF-I levels were inversely related to weight gain overall. Impact Although weight gain was not consistent with increases in IGF-I levels among postmenopausal women in this report, avoidance of weight gain as a strategy to reduce cancer risk may be recommend. PMID:24363252

Metformin for treatment of antipsychotic-induced amenorrhea and weight gain in women with first-episode schizophrenia: a double-blind, randomized, placebo-controlled study.

PubMed

Wu, Ren-Rong; Jin, Hua; Gao, Keming; Twamley, Elizabeth W; Ou, Jian-Jun; Shao, Ping; Wang, Juan; Guo, Xiao-Feng; Davis, John M; Chan, Philip K; Zhao, Jing-Ping

2012-08-01

Data on the treatment of antipsychotic-induced amenorrhea, particularly when occurring with weight gain, are limited. The authors investigated the efficacy and safety of metformin in the treatment of antipsychotic-induced amenorrhea and weight gain in women with first-episode schizophrenia. Eighty-four women (ages 18-40 years) with first-episode schizophrenia who suffered from amenorrhea during antipsychotic treatment were randomly assigned, in a double-blind study design, to receive 1000 mg/day of metformin or placebo in addition to their antipsychotic treatment for 6 months. The primary outcome measures were restoration of menstruation and change in body weight and body mass index (BMI). Secondary outcome measures were changes in levels of prolactin, luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol, and testosterone; in fasting levels of insulin and glucose; in LH/FSH ratio; and in insulin resistance index. Repeated mixed models with repeated-measures regression analyses and binary logistic regression were used in the analysis. A total of 76 patients completed the 6-month trial. Significantly more patients in the metformin group (N=28, 66.7%) than in placebo group (N=2, 4.8%) resumed their menstruation. Among patients treated with metformin, BMI decreased by a mean of 0.93 and the insulin resistance index by 2.04. In contrast, patients who received placebo had a mean increase in BMI of 0.85. The prolactin, LH, and testosterone levels and LH/FSH ratio decreased significantly in the metformin group at months 2, 4, and 6, but these levels did not change in the placebo group. Metformin was effective in reversing antipsychotic-induced adverse events, including restoration of menstruation, promotion of weight loss, and improvement in insulin resistance in female patients with schizophrenia.

Cost-effectiveness of continuous subcutaneous insulin infusion in people with type 2 diabetes in the Netherlands.

PubMed

Roze, S; Duteil, E; Smith-Palmer, J; de Portu, S; Valentine, W; de Brouwer, B F E; Reznik, Y; de Valk, H W

2016-08-01

Up to 30% of insulin-treated type 2 diabetes patients are unable to achieve HbA1c targets despite optimization of insulin multiple daily injections (MDI). For these patients the use of continuous subcutaneous insulin infusion (CSII) represents a useful but under-utilized alternative. The aim of the present analysis was to examine the cost-effectiveness of initiating CSII in type 2 diabetes patients failing to achieve good glycemic control on MDI in the Netherlands. Long-term projections were made using the IMS CORE Diabetes Model. Clinical input data were sourced from the OpT2mise trial. The analysis was performed over a lifetime time horizon. The discount rates applied to future costs and clinical outcomes were 4% and 1.5% per annum, respectively. CSII was associated with improved quality-adjusted life expectancy compared with MDI (9.38 quality-adjusted life years [QALYs] vs 8.95 QALYs, respectively). The breakdown of costs indicated that ∼50% of costs were attributable to diabetes-related complications. Higher acquisition costs of CSII vs MDI were partially offset by the reduction in complications. The ICER was estimated at EUR 62,895 per QALY gained and EUR 60,474 per QALY gained when indirect costs were included. In the Netherlands, CSII represents a cost-effective option in patients with type 2 diabetes who continue to have poorly-controlled HbA1c despite optimization of MDI. Since the ICER falls below the willingness-to-pay threshold of EUR 80,000 per QALY gained, CSII is likely to represent good-value for money in the treatment of poorly-controlled T2D patients compared with MDI.

Small G proteins in insulin action: Rab and Rho families at the crossroads of signal transduction and GLUT4 vesicle traffic.

PubMed

Ishikura, S; Koshkina, A; Klip, A

2008-01-01

Insulin stimulates glucose uptake into muscle and adipose tissues through glucose transporter 4 (GLUT4). GLUT4 cycles between the intracellular compartments and the plasma membrane. GLUT4 traffic-regulating insulin signals are largely within the insulin receptor-insulin receptor substrate-phosphatidylinositol 3-kinase (IR-IRS-PI3K) axis. In muscle cells, insulin signal bifurcates downstream of the PI3K into one arm leading to the activation of the Ser/Thr kinases Akt and atypical protein kinase C, and another leading to the activation of Rho family protein Rac1 leading to actin remodelling. Activated Akt inactivates AS160, a GTPase-activating protein for Rab family small G proteins. Here we review the roles of Rab and Rho proteins, particularly Rab substrates of AS160 and Rac1, in insulin-stimulated GLUT4 traffic. We discuss: (1) how distinct steps in GLUT4 traffic may be regulated by discrete Rab proteins, and (2) the importance of Rac1 activation in insulin-induced actin remodelling in muscle cells, a key element for the net gain in surface GLUT4.

Long-term insulin glargine therapy in type 2 diabetes mellitus: a focus on cardiovascular outcomes

PubMed Central

Joseph, Joshua J; Donner, Thomas W

2015-01-01

Cardiovascular disease is the leading cause of mortality in type 2 diabetes mellitus. Hyperinsulinemia is associated with increased cardiovascular risk, but the effects of exogenous insulin on cardiovascular disease progression have been less well studied. Insulin has been shown to have both cardioprotective and atherosclerosis-promoting effects in laboratory animal studies. Long-term clinical trials using insulin to attain improved diabetes control in younger type 1 and type 2 diabetes patients have shown improved cardiovascular outcomes. Shorter trials of intensive diabetes control with high insulin use in higher risk patients with type 2 diabetes have shown either no cardiovascular benefit or increased all cause and cardiovascular mortality. Glargine insulin is a basal insulin analog widely used to treat patients with type 1 and type 2 diabetes. This review focuses on the effects of glargine on cardiovascular outcomes. Glargine lowers triglycerides, leads to a modest weight gain, causes less hypoglycemia when compared with intermediate-acting insulin, and has a neutral effect on blood pressure. The Outcome Reduction With Initial Glargine Intervention (ORIGIN trial), a 6.2 year dedicated cardiovascular outcomes trial of glargine demonstrated no increased cardiovascular risk. PMID:25657589

Phenformin in Insulin-Dependent Diabetics

PubMed Central

Bloom, Arnold; Kolbe, R. J.

1970-01-01

Forty-one diabetic patients on insulin were given 100mg. of phenformin daily for six weeks, either before or after a period of six weeks of inert capsules, in a double-blind cross-over trial. Eleven patients while on phenformin noticed hypoglycaemic effects and reduced their insulin on average by almost 20% without resultant rise in blood sugar levels. Twenty-eight patients felt no untoward effects and maintained their usual insulin dose. Phenformin led to improved control of the diabetes, with a significant decrease in blood sugar levels and a significant reduction in the variability of the weekly blood sugar readings. There was no increased ketosis, no change in cholesterol, and no significant loss of weight. PMID:4914612

Effects of exposure to artificial long days on milk yield, maternal insulin-like growth factor 1 levels and kid growth rate in subtropical goats.

PubMed

Hernández, Horacio; Flores, José Alfredo; Delgadillo, José Alberto; Fernández, Ilda G; Flores, Manuel de Jesús; Mejía, Ángel; Elizundia, José Manuel; Bedos, Marie; Ponce, José Luis; Ramírez, Sergio

2016-04-01

This study was designed to determine whether any relationship exists between exposure to artificial long days, milk yield, maternal plasma insulin-like growth factor 1 (IGF-1) levels, and kid growth rate in goats. One group of lactating goats was maintained under naturally decreasing day length (control group; n = 19), while in another one, they were kept under artificial long days (LD group; n = 19). Milk yield was higher in goats from the LD group than that in the control group (P < 0.05). Maternal IGF-1 levels at day 57 of lactation were higher (P < 0.05) in goats from the LD group than the levels in the control group and were positively correlated with the total milk yields per goat at days 43 and 57 of lactation (r = 0.77 and r = 0.84, respectively; P < 0.01). Daily weight gain at week 4 was higher (P < 0.01) in kids from the LD group than that in kids from the control group and was correlated with total and average IGF-1 maternal levels (r = 0.60 and r = 0.60, P < 0.05). It was concluded that submitting lactating goats to artificial long days increases milk yield, plasma IGF-1 maternal levels and the growth rate of the kids. © 2015 Japanese Society of Animal Science.

Moving beyond the illness: factors contributing to gaining and maintaining employment.

PubMed

Cunningham, K; Wolbert, R; Brockmeier, M B

2000-08-01

The work presented here, exploratory in nature, uses a comparative and qualitative approach to understand the factors associated with the ability of individuals with severe and persistent mental illness to successfully gain and maintain employment. Based on open-ended interviews with individuals in an Assertive Community Treatment (ACT) program, we compare the experiences of those who have been successful gaining and maintaining employment, with those who have been successful gaining but not maintaining work, and those who have been unsuccessful gaining employment. The three groups seemed to differ in three significant ways: (1) in the ways the individuals talked about their illness, (2) in the ways the individuals talked about work, and (3) in the strategies they described for coping with bad days. In each of these areas individuals' awareness of and attitude toward their illness was significant. The findings have clear implications for agencies working to help people with severe and persistent mental illness obtain and maintain employment.

Effects of Insulin Detemir and NPH Insulin on Body Weight and Appetite-Regulating Brain Regions in Human Type 1 Diabetes: A Randomized Controlled Trial

PubMed Central

van Golen, Larissa W.; Veltman, Dick J.; IJzerman, Richard G.; Deijen, Jan Berend; Heijboer, Annemieke C.; Barkhof, Frederik; Drent, Madeleine L.; Diamant, Michaela

2014-01-01

Studies in rodents have demonstrated that insulin in the central nervous system induces satiety. In humans, these effects are less well established. Insulin detemir is a basal insulin analog that causes less weight gain than other basal insulin formulations, including the current standard intermediate-long acting Neutral Protamine Hagedorn (NPH) insulin. Due to its structural modifications, which render the molecule more lipophilic, it was proposed that insulin detemir enters the brain more readily than other insulins. The aim of this study was to investigate whether insulin detemir treatment differentially modifies brain activation in response to food stimuli as compared to NPH insulin. In addition, cerebral spinal fluid (CSF) insulin levels were measured after both treatments. Brain responses to viewing food and non-food pictures were measured using functional Magnetic Resonance Imaging in 32 type 1 diabetic patients, after each of two 12-week treatment periods with insulin detemir and NPH insulin, respectively, both combined with prandial insulin aspart. CSF insulin levels were determined in a subgroup. Insulin detemir decreased body weight by 0.8 kg and NPH insulin increased weight by 0.5 kg (p = 0.02 for difference), while both treatments resulted in similar glycemic control. After treatment with insulin detemir, as compared to NPH insulin, brain activation was significantly lower in bilateral insula in response to visual food stimuli, compared to NPH (p = 0.02 for right and p = 0.05 for left insula). Also, CSF insulin levels were higher compared to those with NPH insulin treatment (p = 0.003). Our findings support the hypothesis that in type 1 diabetic patients, the weight sparing effect of insulin detemir may be mediated by its enhanced action on the central nervous system, resulting in blunted activation in bilateral insula, an appetite-regulating brain region, in response to food stimuli. Trial Registration ClinicalTrials.gov NCT00626080. PMID:24739875

Effects of insulin detemir and NPH insulin on body weight and appetite-regulating brain regions in human type 1 diabetes: a randomized controlled trial.

PubMed

van Golen, Larissa W; Veltman, Dick J; IJzerman, Richard G; Deijen, Jan Berend; Heijboer, Annemieke C; Barkhof, Frederik; Drent, Madeleine L; Diamant, Michaela

2014-01-01

Studies in rodents have demonstrated that insulin in the central nervous system induces satiety. In humans, these effects are less well established. Insulin detemir is a basal insulin analog that causes less weight gain than other basal insulin formulations, including the current standard intermediate-long acting Neutral Protamine Hagedorn (NPH) insulin. Due to its structural modifications, which render the molecule more lipophilic, it was proposed that insulin detemir enters the brain more readily than other insulins. The aim of this study was to investigate whether insulin detemir treatment differentially modifies brain activation in response to food stimuli as compared to NPH insulin. In addition, cerebral spinal fluid (CSF) insulin levels were measured after both treatments. Brain responses to viewing food and non-food pictures were measured using functional Magnetic Resonance Imaging in 32 type 1 diabetic patients, after each of two 12-week treatment periods with insulin detemir and NPH insulin, respectively, both combined with prandial insulin aspart. CSF insulin levels were determined in a subgroup. Insulin detemir decreased body weight by 0.8 kg and NPH insulin increased weight by 0.5 kg (p = 0.02 for difference), while both treatments resulted in similar glycemic control. After treatment with insulin detemir, as compared to NPH insulin, brain activation was significantly lower in bilateral insula in response to visual food stimuli, compared to NPH (p = 0.02 for right and p = 0.05 for left insula). Also, CSF insulin levels were higher compared to those with NPH insulin treatment (p = 0.003). Our findings support the hypothesis that in type 1 diabetic patients, the weight sparing effect of insulin detemir may be mediated by its enhanced action on the central nervous system, resulting in blunted activation in bilateral insula, an appetite-regulating brain region, in response to food stimuli. ClinicalTrials.gov NCT00626080.

De Novo Lipogenesis Maintains Vascular Homeostasis through Endothelial Nitric-oxide Synthase (eNOS) Palmitoylation*♦

PubMed Central

Wei, Xiaochao; Schneider, Jochen G.; Shenouda, Sherene M.; Lee, Ada; Towler, Dwight A.; Chakravarthy, Manu V.; Vita, Joseph A.; Semenkovich, Clay F.

2011-01-01

Endothelial dysfunction leads to lethal vascular complications in diabetes and related metabolic disorders. Here, we demonstrate that de novo lipogenesis, an insulin-dependent process driven by the multifunctional enzyme fatty-acid synthase (FAS), maintains endothelial function by targeting endothelial nitric-oxide synthase (eNOS) to the plasma membrane. In mice with endothelial inactivation of FAS (FASTie mice), eNOS membrane content and activity were decreased. eNOS and FAS were physically associated; eNOS palmitoylation was decreased in FAS-deficient cells, and incorporation of labeled carbon into eNOS-associated palmitate was FAS-dependent. FASTie mice manifested a proinflammatory state reflected as increases in vascular permeability, endothelial inflammatory markers, leukocyte migration, and susceptibility to LPS-induced death that was reversed with an NO donor. FAS-deficient endothelial cells showed deficient migratory capacity, and angiogenesis was decreased in FASTie mice subjected to hindlimb ischemia. Insulin induced FAS in endothelial cells freshly isolated from humans, and eNOS palmitoylation was decreased in mice with insulin-deficient or insulin-resistant diabetes. Thus, disrupting eNOS bioavailability through impaired lipogenesis identifies a novel mechanism coordinating nutritional status and tissue repair that may contribute to diabetic vascular disease. PMID:21098489

Loss of end-differentiated β-cell phenotype following pancreatic islet transplantation.

PubMed

Anderson, S J; White, M G; Armour, S L; Maheshwari, R; Tiniakos, D; Muller, Y D; Berishvili, E; Berney, T; Shaw, J A M

2018-03-01

Replacement of pancreatic β-cells through deceased donor islet transplantation is a proven therapy for preventing recurrent life-threatening hypoglycemia in type 1 diabetes. Although near-normal glucose levels and insulin independence can be maintained for many years following successful islet transplantation, restoration of normal functional β-cell mass has remained elusive. It has recently been proposed that dedifferentiation/plasticity towards other endocrine phenotypes may play an important role in stress-induced β-cell dysfunction in type 2 diabetes. Here we report loss of end-differentiated β-cell phenotype in 2 intraportal islet allotransplant recipients. Despite excellent graft function and sustained insulin independence, all examined insulin-positive cells had lost expression of the end-differentiation marker, urocortin-3, or appeared to co-express the α-cell marker, glucagon. In contrast, no insulin + /urocortin-3 - cells were seen in nondiabetic deceased donor control pancreatic islets. Loss of end-differentiated phenotype may facilitate β-cell survival during the stresses associated with islet isolation and culture, in addition to sustained hypoxia following engraftment. As further refinements in islet isolation and culture are made in parallel with exploration of alternative β-cell sources, graft sites, and ultimately fully vascularized bioengineered insulin-secreting microtissues, differentiation status immunostaining provides a novel tool to assess whether fully mature β-cell phenotype has been maintained. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

Maintaining euglycemia prevents insulin-induced Fos expression in brain autonomic regulatory circuits.

PubMed

Ao, Yan; Wu, Shuying; Go, Vay Liang W; Toy, Natalie; Yang, Hong

2005-08-01

Insulin-induced hypoglycemia activates neurons in hypothalamic and brain medullary nuclei involved in central autonomic regulation. We investigated whether these central neuronal activations relates to a deficiency of glucose supply. Three groups of non-fasted, conscious rats received intravenous (iv) saline infusion (control), a hyperinsulinemic/hypoglycemic clamp, or a hyperinsulinemic/euglycemic clamp for 120 minutes and then the brains were collected for Fos immunohistochemistry. The number of Fos positive cells significantly increased in the paraventricular nucleus of the hypothalamus (PVN, 191 +/- 63 versus 66 +/- 18), pontine locus coeruleus (LC, 53 +/- 19 versus 5 +/- 2), brain medullary dorsal motor nucleus of the vagus (DMV, 26 +/- 4 versus 1 +/- 0), and nucleus tractus solitarii (NTS, 38 +/- 3 versus 10 +/- 35) in rats with hyperinsulinemic/hypoglycemic clamp compared with the controls. Maintaining blood glucose levels within physiological range by hyperinsulinemic/euglycemic clamp prevented insulin infusion-induced Fos expression in the PVN, DMV, and NTS. The numbers of Fos positive cells in these nuclei were significantly lower (-87%, -75%, and -51%, respectively) than that in the hypoglycemic rats. These results indicate that neuronal activation in hypothalamic and medullary autonomic regulatory nuclei induced by insulin administration is caused by hypoglycemia rather than a direct action of insulin. In addition, certain neurons in the medullary DMV and NTS respond to declines in glucose levels within physiological range.

Lifestyle and Weight Predictors of a Healthy Overweight Profile over a 20 year Follow-up

PubMed Central

Fung, Michael; Canning, Karissa L.; Mirdamadi, Paul; Ardern, Chris I.; Kuk, Jennifer L.

2016-01-01

Objectives To examine whether changes in modifiable risk factors (physical activity, cardiorespiratory fitness (CRF), body weight and diet composition) are associated with the transition to metabolically healthy overweight/obese (MHO) versus metabolically abnormal overweight/obese. Methods This analysis included 1358 adults (aged 25.0 (3.5) years) from the CARDIA study who were healthy at baseline and overweight/obese at follow-up. Participants with zero or one of the following six risk factors were classified as MHO: elevated triglycerides, LDL, blood pressure, fasting glucose and HOMA-insulin resistance and low HDL. Results Over the 20 year follow-up, the sample gained weight (BMI 24.5 kg/m2 to 31.1 kg/m2) and the prevalence of MHO was 47% of overweight/obese at follow-up. After adjusting for changes in CRF, diet and weight change, physical activity and macronutrient intake were not independently associated with MHO (p>0.05), while changes in CRF (fit-unfit: RR (95%) = 0.58, 0.52–0.66; unfit-unfit: RR = 0.67, 0.58–0.76, versus fit-fit) and weight (gain: RR (95%) = 0.54, 0.43–0.67; cycle: RR = 0.74, 0.57–0.94; versus stable) were independently associated with MHO. Conclusion Focusing on high CRF and strategies to limit weight gain may be important for individuals with overweight and obesity in early to mid-adulthood to maintain a metabolically healthy profile. PMID:26010328

Control of hepatic glucose metabolism by islet and brain.

PubMed

Rojas, J M; Schwartz, M W

2014-09-01

Dysregulation of hepatic glucose uptake (HGU) and inability of insulin to suppress hepatic glucose production (HGP) contribute to hyperglycaemia in patients with type 2 diabetes (T2D). Growing evidence suggests that insulin can inhibit HGP not only through a direct effect on the liver but also through a mechanism involving the brain. Yet, the notion that insulin action in the brain plays a physiological role in the control of HGP continues to be controversial. Although studies in dogs suggest that the direct hepatic effect of insulin is sufficient to explain day-to-day control of HGP, a surprising outcome has been revealed by recent studies in mice, investigating whether the direct hepatic action of insulin is necessary for normal HGP: when the hepatic insulin signalling pathway was genetically disrupted, HGP was maintained normally even in the absence of direct input from insulin. Here, we present evidence that points to a potentially important role of the brain in the physiological control of both HGU and HGP in response to input from insulin as well as other hormones and nutrients. © 2014 John Wiley & Sons Ltd.

Initiation of once daily insulin detemir is not associated with weight gain in patients with type 2 diabetes mellitus: results from an observational study

PubMed Central

2013-01-01

Background Obesity is common in type 2 diabetes (T2DM) and is associated with increased risk of morbidity and all-cause mortality. This analysis describes weight changes associated with insulin detemir initiation in real-life clinical practice. Methods Study of Once-Daily Levemir (SOLVE) was a 24-week international observational study of once-daily insulin detemir as add-on therapy in patients with T2DM receiving oral hypoglycaemic agents (OHAs). Results 17,374 participants were included in the analysis: mean age 62 ± 12 years; weight 80.8 ± 17.6 kg; body mass index (BMI) 29.2 ± 5.3 kg/m2; diabetes duration 10 ± 7 years; HbA1c 8.9 ± 1.6%. HbA1c decreased by 1.3 ± 1.5% during the study, with insulin doses of 0.27 ± 0.17 IU/kg. Patients with higher BMI had higher pre-insulin HbA1c, and similar reductions in HbA1c with insulin therapy. Weight decreased from 80.8 ± 17.6 kg to 80.3 ± 17.0 kg (change of -0.6 [95% CI -0.65; -0.47] kg), with 35% of patients losing >1 kg. Patients with the highest pre-insulin BMI lost the greatest amount of weight: BMI < 25: +0.8 [95% CI: 0.6; 0.9] kg, 25 ≤ BMI < 30: -0.2 [95% CI: -0.3; -0.8] kg, 30 ≤ BMI < 35: -1.0 [95% CI: -1.1; -0.8] kg; BMI ≥ 35: -1.9 [95% CI: -2.2; -1.6] kg. Minor hypoglycaemia decreased with increasing BMI: 2.3 and 1.3 events per patient year for BMI <25 and  ≥ 35, respectively. Conclusions Overall, patients with poorly controlled T2DM achieved significant reductions in HbA1c after initiation of once-daily insulin detemir therapy, without weight gain. The favourable impact of insulin detemir on weight may not apply to other insulin preparations. Trial registrations ClinicalTrials.gov, NCT00825643 and NCT00740519 PMID:24499517

Cost-effectiveness of exenatide twice daily vs insulin glargine as add-on therapy to oral antidiabetic agents in patients with type 2 diabetes in China.

PubMed

Gu, Shuyan; Wang, Xiaoyong; Qiao, Qing; Gao, Weiguo; Wang, Jian; Dong, Hengjin

2017-12-01

To estimate the long-term cost-effectiveness of exenatide twice daily vs insulin glargine once daily as add-on therapy to oral antidiabetic agents (OADs) for Chinese patients with type 2 diabetes (T2DM). The Cardiff Diabetes Model was used to simulate disease progression and estimate the long-term effects of exenatide twice daily vs insulin glargine once daily. Patient profiles and treatment effects required for the model were obtained from literature reviews (English and Chinese databases) and from a meta-analysis of 8 randomized controlled trials comparing exenatide twice daily with insulin glargine once daily add-on to OADs for T2DM in China. Medical expenditure data were collected from 639 patients with T2DM (aged ≥18 years) with and without complications incurred between January 1, 2014 and December 31, 2015 from claims databases in Shandong, China. Costs (2014 Chinese Yuan [¥]) and benefits were estimated, from the payers' perspective, over 40 years at a discount rate of 3%. A series of sensitivity analyses were performed. Patients on exenatide twice daily + OAD had a lower predicted incidence of most cardiovascular and hypoglycaemic events and lower total costs compared with those on insulin glargine once daily + OAD. A greater number of quality-adjusted life years (QALYs; 1.94) at a cost saving of ¥117 706 gained was associated with exenatide twice daily vs insulin glargine once daily. (i.e. cost saving of ¥60 764/QALY) per patient. In Chinese patients with T2DM inadequately controlled by OADs, exenatide twice daily is a cost-effective add-on therapy alternative to insulin glargine once daily, and may address the problem of an excess of medical needs resulting from weight gain and hypoglycaemia in T2DM treatment. © 2017 John Wiley & Sons Ltd.

Oral delivery of insulin for treatment of diabetes: status quo, challenges and opportunities.

PubMed

Wong, Chun Y; Martinez, Jorge; Dass, Crispin R

2016-09-01

Diabetes mellitus is characterised by progressive β-cell destruction and loss of function, or loss of ability of tissues to respond to insulin. Daily subcutaneous insulin injection is standard management for people with diabetes, although patient compliance is hard to achieve due to the inconvenience of injections, so other forms of delivery are being tested, including oral administration. This review summarises the developments in oral insulin administration. The PubMed database was consulted to compile this review comparing conventional subcutaneous injection of insulin to the desired oral delivery. Oral administration of insulin has potential benefits in reducing pain and chances of skin infection, improving the portal levels of insulin and avoiding side effects such as hyperinsulinemia, weight gain and hypoglycaemia. Although oral delivery of insulin is an ideal administration route for patients with diabetes, several physiological barriers have to be overcome. An expected low oral bioavailability can be attributed to its high molecular weight, susceptibility to enzymatic proteolysis and low diffusion rate across the mucin barrier. Strategies for increasing the bioavailability of oral insulin include the use of enzyme inhibitors, absorption enhancers, mucoadhesive polymers and chemical modification for endogenous receptor-mediated absorption. These may help significantly increase patient compliance and disease management. © 2016 Royal Pharmaceutical Society.

SIRT1 Gain of Function Does Not Mimic or Enhance the Adaptations to Intermittent Fasting.

PubMed

Boutant, Marie; Kulkarni, Sameer S; Joffraud, Magali; Raymond, Frédéric; Métairon, Sylviane; Descombes, Patrick; Cantó, Carles

2016-03-08

Caloric restriction (CR) has been shown to prevent the onset of insulin resistance and to delay age-related physiological decline in mammalian organisms. SIRT1, a NAD(+)-dependent deacetylase enzyme, has been suggested to mediate the adaptive responses to CR, leading to the speculation that SIRT1 activation could be therapeutically used as a CR-mimetic strategy. Here, we used a mouse model of moderate SIRT1 overexpression to test whether SIRT1 gain of function could mimic or boost the metabolic benefits induced by every-other-day feeding (EODF). Our results indicate that SIRT1 transgenesis does not affect the ability of EODF to decrease adiposity and improve insulin sensitivity. Transcriptomic analyses revealed that SIRT1 transgenesis and EODF promote very distinct adaptations in individual tissues, some of which can be even be metabolically opposite, as in brown adipose tissue. Therefore, whereas SIRT1 overexpression and CR both improve glucose metabolism and insulin sensitivity, the etiologies of these benefits are largely different. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

'I don't feel like a diabetic any more': the impact of stopping insulin in patients with maturity onset diabetes of the young following genetic testing.

PubMed

Shepherd, Maggie; Hattersley, Andrew T

2004-01-01

Hepatocyte nuclear factor-1alpha (HNF-1alpha) maturity onset diabetes of the young (MODY) is the commonest cause of monogenic diabetes but is frequently misdiagnosed as type 1 diabetes. The availability of genetic testing in MODY has improved diagnosis. Sulphonylurea sensitivity in HNF-1alpha patients means that those on insulin from diagnosis can transfer to sulphonylureas and may improve glycaemic control. To gain insight into the implications for patients of stopping insulin, in-depth interviews were conducted with eight HNF-1alpha patients transferred to sulphonylureas after a median of 20 years on insulin. Thematic content analysis highlighted four key themes: Fear, anxiety and excitement regarding stopping insulin, particularly among those who had been on insulin for many years or had never omitted insulin in the past. Improved lifestyle and self image accompanied by feelings of relief and 'increased normality'. Reflections on their time on insulin, including feelings of annoyance, particularly when the need for insulin treatment had been questioned at diagnosis. Difficulty 'letting go' of insulin treatment--some patients found it hard to believe that they no longer required injections as this conflicted with messages previously received from healthcare professionals. Transferring from insulin to sulphonylureas had a positive impact on lifestyle but support was needed for patients to adjust, many having grown up with the belief they would be on insulin for life.

A small amount of dietary carbohydrate can promote the HFD-induced insulin resistance to a maximal level.

PubMed

Mei, Shuang; Yang, Xuefeng; Guo, Huailan; Gu, Haihua; Zha, Longying; Cai, Junwei; Li, Xuefeng; Liu, Zhenqi; Bennett, Brian J; He, Ling; Cao, Wenhong

2014-01-01

Both dietary fat and carbohydrates (Carbs) may play important roles in the development of insulin resistance. The main goal of this study was to further define the roles for fat and dietary carbs in insulin resistance. C57BL/6 mice were fed normal chow diet (CD) or HFD containing 0.1-25.5% carbs for 5 weeks, followed by evaluations of calorie consumption, body weight and fat gains, insulin sensitivity, intratissue insulin signaling, ectopic fat, and oxidative stress in liver and skeletal muscle. The role of hepatic gluconeogenesis in the HFD-induced insulin resistance was determined in mice. The role of fat in insulin resistance was also examined in cultured cells. HFD with little carbs (0.1%) induced severe insulin resistance. Addition of 5% carbs to HFD dramatically elevated insulin resistance and 10% carbs in HFD was sufficient to induce a maximal level of insulin resistance. HFD with little carbs induced ectopic fat accumulation and oxidative stress in liver and skeletal muscle and addition of carbs to HFD dramatically enhanced ectopic fat and oxidative stress. HFD increased hepatic expression of key gluconeogenic genes and the increase was most dramatic by HFD with little carbs, and inhibition of hepatic gluconeogenesis prevented the HFD-induced insulin resistance. In cultured cells, development of insulin resistance induced by a pathological level of insulin was prevented in the absence of fat. Together, fat is essential for development of insulin resistance and dietary carb is not necessary for HFD-induced insulin resistance due to the presence of hepatic gluconeogenesis but a very small amount of it can promote HFD-induced insulin resistance to a maximal level.

A Small Amount of Dietary Carbohydrate Can Promote the HFD-Induced Insulin Resistance to a Maximal Level

PubMed Central

Guo, Huailan; Gu, Haihua; Zha, Longying; Cai, Junwei; Li, Xuefeng; Liu, Zhenqi; Bennett, Brian J.; He, Ling; Cao, Wenhong

2014-01-01

Both dietary fat and carbohydrates (Carbs) may play important roles in the development of insulin resistance. The main goal of this study was to further define the roles for fat and dietary carbs in insulin resistance. C57BL/6 mice were fed normal chow diet (CD) or HFD containing 0.1–25.5% carbs for 5 weeks, followed by evaluations of calorie consumption, body weight and fat gains, insulin sensitivity, intratissue insulin signaling, ectopic fat, and oxidative stress in liver and skeletal muscle. The role of hepatic gluconeogenesis in the HFD-induced insulin resistance was determined in mice. The role of fat in insulin resistance was also examined in cultured cells. HFD with little carbs (0.1%) induced severe insulin resistance. Addition of 5% carbs to HFD dramatically elevated insulin resistance and 10% carbs in HFD was sufficient to induce a maximal level of insulin resistance. HFD with little carbs induced ectopic fat accumulation and oxidative stress in liver and skeletal muscle and addition of carbs to HFD dramatically enhanced ectopic fat and oxidative stress. HFD increased hepatic expression of key gluconeogenic genes and the increase was most dramatic by HFD with little carbs, and inhibition of hepatic gluconeogenesis prevented the HFD-induced insulin resistance. In cultured cells, development of insulin resistance induced by a pathological level of insulin was prevented in the absence of fat. Together, fat is essential for development of insulin resistance and dietary carb is not necessary for HFD-induced insulin resistance due to the presence of hepatic gluconeogenesis but a very small amount of it can promote HFD-induced insulin resistance to a maximal level. PMID:25055153

A human beta cell line with drug inducible excision of immortalizing transgenes

PubMed Central

Benazra, Marion; Lecomte, Marie-José; Colace, Claire; Müller, Andreas; Machado, Cécile; Pechberty, Severine; Bricout-Neveu, Emilie; Grenier-Godard, Maud; Solimena, Michele; Scharfmann, Raphaël; Czernichow, Paul; Ravassard, Philippe

2015-01-01

Objectives Access to immortalized human pancreatic beta cell lines that are phenotypically close to genuine adult beta cells, represent a major tool to better understand human beta cell physiology and develop new therapeutics for Diabetes. Here we derived a new conditionally immortalized human beta cell line, EndoC-βH3 in which immortalizing transgene can be efficiently removed by simple addition of tamoxifen. Methods We used lentiviral mediated gene transfer to stably integrate a tamoxifen inducible form of CRE (CRE-ERT2) into the recently developed conditionally immortalized EndoC βH2 line. The resulting EndoC-βH3 line was characterized before and after tamoxifen treatment for cell proliferation, insulin content and insulin secretion. Results We showed that EndoC-βH3 expressing CRE-ERT2 can be massively amplified in culture. We established an optimized tamoxifen treatment to efficiently excise the immortalizing transgenes resulting in proliferation arrest. In addition, insulin expression raised by 12 fold and insulin content increased by 23 fold reaching 2 μg of insulin per million cells. Such massive increase was accompanied by enhanced insulin secretion upon glucose stimulation. We further observed that tamoxifen treated cells maintained a stable function for 5 weeks in culture. Conclusions EndoC βH3 cell line represents a powerful tool that allows, using a simple and efficient procedure, the massive production of functional non-proliferative human beta cells. Such cells are close to genuine human beta cells and maintain a stable phenotype for 5 weeks in culture. PMID:26909308

Fed levels of amino acids are required for the somatotropin-induced increase in muscle protein synthesis

PubMed Central

Wilson, Fiona A.; Suryawan, Agus; Orellana, Renán A.; Nguyen, Hanh V.; Jeyapalan, Asumthia S.; Gazzaneo, Maria C.; Davis, Teresa A.

2008-01-01

Chronic somatotropin (pST) treatment in pigs increases muscle protein synthesis and circulating insulin, a known promoter of protein synthesis. Previously, we showed that the pST-mediated rise in insulin could not account for the pST-induced increase in muscle protein synthesis when amino acids were maintained at fasting levels. This study aimed to determine whether the pST-induced increase in insulin promotes skeletal muscle protein synthesis when amino acids are provided at fed levels and whether the response is associated with enhanced translation initiation factor activation. Growing pigs were treated with pST (0 or 180 μg·kg−1·day−1) for 7 days, and then pancreatic-glucose-amino acid clamps were performed. Amino acids were raised to fed levels in the presence of either fasted or fed insulin concentrations; glucose was maintained at fasting throughout. Muscle protein synthesis was increased by pST treatment and by amino acids (with or without insulin) (P < 0.001). In pST-treated pigs, fed, but not fasting, amino acid concentrations further increased muscle protein synthesis rates irrespective of insulin level (P < 0.02). Fed amino acids, with or without raised insulin concentrations, increased the phosphorylation of S6 kinase (S6K1) and eukaryotic initiation factor (eIF) 4E-binding protein 1 (4EBP1), decreased inactive 4EBP1·eIF4E complex association, and increased active eIF4E·eIF4G complex formation (P < 0.02). pST treatment did not alter translation initiation factor activation. We conclude that the pST-induced stimulation of muscle protein synthesis requires fed amino acid levels, but not fed insulin levels. However, under the current conditions, the response to amino acids is not mediated by the activation of translation initiation factors that regulate mRNA binding to the ribosomal complex. PMID:18682537

Fed levels of amino acids are required for the somatotropin-induced increase in muscle protein synthesis.

PubMed

Wilson, Fiona A; Suryawan, Agus; Orellana, Renán A; Nguyen, Hanh V; Jeyapalan, Asumthia S; Gazzaneo, Maria C; Davis, Teresa A

2008-10-01

Chronic somatotropin (pST) treatment in pigs increases muscle protein synthesis and circulating insulin, a known promoter of protein synthesis. Previously, we showed that the pST-mediated rise in insulin could not account for the pST-induced increase in muscle protein synthesis when amino acids were maintained at fasting levels. This study aimed to determine whether the pST-induced increase in insulin promotes skeletal muscle protein synthesis when amino acids are provided at fed levels and whether the response is associated with enhanced translation initiation factor activation. Growing pigs were treated with pST (0 or 180 microg x kg(-1) x day(-1)) for 7 days, and then pancreatic-glucose-amino acid clamps were performed. Amino acids were raised to fed levels in the presence of either fasted or fed insulin concentrations; glucose was maintained at fasting throughout. Muscle protein synthesis was increased by pST treatment and by amino acids (with or without insulin) (P<0.001). In pST-treated pigs, fed, but not fasting, amino acid concentrations further increased muscle protein synthesis rates irrespective of insulin level (P<0.02). Fed amino acids, with or without raised insulin concentrations, increased the phosphorylation of S6 kinase (S6K1) and eukaryotic initiation factor (eIF) 4E-binding protein 1 (4EBP1), decreased inactive 4EBP1.eIF4E complex association, and increased active eIF4E.eIF4G complex formation (P<0.02). pST treatment did not alter translation initiation factor activation. We conclude that the pST-induced stimulation of muscle protein synthesis requires fed amino acid levels, but not fed insulin levels. However, under the current conditions, the response to amino acids is not mediated by the activation of translation initiation factors that regulate mRNA binding to the ribosomal complex.

Massage Changes Babies' Body, Brain and Behavior

NASA Astrophysics Data System (ADS)

Ishikawa, Chihiro; Shiga, Takashi

Tactile stimulation is an important factor in mother-infant interactions. Many studies on both human and animals have shown that tactile stimulation during the neonatal period has various beneficial effects in the subsequent growth of the body and brain. In particular, massage is often applied to preterm human babies as “touch care”, because tactile stimulation together with kinesthetic stimulation increases body weight, which is accompanied by behavioral development and the changes of endocrine and neural conditions. Among them, the elevation of insulin-like growth factor-1, catecholamine, and vagus nerve activity may underlie the body weight gain. Apart from the body weight gain, tactile stimulation has various effects on the nervous system and endocrine system. For example, it has been reported that tactile stimulation on human and animal babies activates parasympathetic nervous systems, while suppresses the hypothalamic-pituitary-adrenalcortical (HPA) axis, which may be related to the reduction of emotionality, anxiety-like behavior, and pain sensitivity. In addition, animal experiments have shown that tactile stimulation improves learning and memory. Facilitation of the neuronal activity and the morphological changes including the hippocampal synapse may underlie the improvement of the learning and memory. In conclusion, it has been strongly suggested that tactile stimulation in early life has beneficial effects on body, brain structure and function, which are maintained throughout life.

Voluntary wheel running selectively augments insulin-stimulated vasodilation in arterioles from white skeletal muscle of insulin-resistant rats.

PubMed

Mikus, Catherine R; Roseguini, Bruno T; Uptergrove, Grace M; Morris, E Matthew; Rector, Randy Scott; Libla, Jessica L; Oberlin, Douglas J; Borengasser, Sarah J; Taylor, Angelina M; Ibdah, Jamal A; Laughlin, Maurice Harold; Thyfault, John P

2012-11-01

Exercise (RUN) prevents declines in insulin-mediated vasodilation, an important component of insulin-mediated glucose disposal, in rats prone to obesity and insulin resistance. Determine whether RUN (1) improves insulin-stimulated vasodilation after insulin resistance has been established, and (2) differentially affects arterioles from red and white muscle. Insulin signaling and vasoreactivity to insulin (1-1000 μIU/mL) were assessed in 2A from the Gw and Gr of SED OLETF rats at 12 and 20 weeks of age (SED12, SED20) and those undergoing RUN (RUN20) or caloric restriction (CR20; to match body weight of RUN) from 12 to 20 weeks. Glucose and insulin responses to i.p. glucose were reduced in RUN20, elevated in SED20 (p < 0.05 vs. SED12), and maintained in CR20. Insulin-stimulated vasodilation was greater in Gw but not Gr, 2As of RUN20 (p < 0.01 vs. all groups), and was improved by ET-1 receptor inhibition in Gw 2As from SED20 and CR20 (p < 0.05). There were no differences in microvascular insulin signaling among groups or muscle beds. RUN selectively improved insulin-mediated vasodilation in Gw 2As, in part through attenuated ET-1 sensitivity/production, an adaptation that was independent of changes in adiposity and may contribute to enhanced insulin-stimulated glucose disposal. © 2012 John Wiley & Sons Ltd.

Simulation-Based Evaluation of Dose-Titration Algorithms for Rapid-Acting Insulin in Subjects with Type 2 Diabetes Mellitus Inadequately Controlled on Basal Insulin and Oral Antihyperglycemic Medications.

PubMed

Ma, Xiaosu; Chien, Jenny Y; Johnson, Jennal; Malone, James; Sinha, Vikram

2017-08-01

The purpose of this prospective, model-based simulation approach was to evaluate the impact of various rapid-acting mealtime insulin dose-titration algorithms on glycemic control (hemoglobin A1c [HbA1c]). Seven stepwise, glucose-driven insulin dose-titration algorithms were evaluated with a model-based simulation approach by using insulin lispro. Pre-meal blood glucose readings were used to adjust insulin lispro doses. Two control dosing algorithms were included for comparison: no insulin lispro (basal insulin+metformin only) or insulin lispro with fixed doses without titration. Of the seven dosing algorithms assessed, daily adjustment of insulin lispro dose, when glucose targets were met at pre-breakfast, pre-lunch, and pre-dinner, sequentially, demonstrated greater HbA1c reduction at 24 weeks, compared with the other dosing algorithms. Hypoglycemic rates were comparable among the dosing algorithms except for higher rates with the insulin lispro fixed-dose scenario (no titration), as expected. The inferior HbA1c response for the "basal plus metformin only" arm supports the additional glycemic benefit with prandial insulin lispro. Our model-based simulations support a simplified dosing algorithm that does not include carbohydrate counting, but that includes glucose targets for daily dose adjustment to maintain glycemic control with a low risk of hypoglycemia.

Breast feeding and insulin levels in low birth weight neonates: a randomized study.

PubMed

Gupta, Mukesh; Zaheer; Jora, Rakesh; Kaul, Vijay; Gupta, Rajeev

2010-05-01

To evaluate the influence of early infancy feeding practices on fasting insulin levels, as marker of insulin resistance, in low birthweight neonates. Eighty successive low birth weight (<2.5 kg) neonates <10 days of age born at >38 wk of gestation at this tertiary care centre, were successively invited for participation in the study; parents of 52 (65%) consented to participate. Group 1 children (n=26) were randomized to receive only breast feeding and Group 2 (n=26) received fortified breast feeding with a commercially available human milk fortifier. Routine anthropometry and evaluation of health status was performed. The babies were followed-up every 15 day up to three months. 4-hour fasting glucose and insulin levels were measured at baseline and at 3 month. Statistical analyses were performed using t-test and Mann-Whitney test. In excusively breast-fed Group 1 neonates vs Group 2 the mean birthweight was similar (1.99+/-0.23 vs 1.87+/-0.30 kg). There was no difference in body length, head circumference and chest circumference. Mean hemoglobin levels, fasting glucose (63.9+/-9.8 vs 64.3+/-8.0 mg/dl) and fasting insulin levels (1.44+/-1.19 vs 1.73+/-1.38 microU/ml), were also similar. At three month follow-up in Group 1 children receiving exclusive breast feeding, there was significantly lower weight as compared to Group 2 (3.40+/-0.3 vs 4.75+/-0.5 kg, p<0.01). This was associated with significantly lower fasting glucose (79.0+/-9.4 vs 85.6+/-8.4 mg/dl) and fasting insulin levels (6.95+/-4.27 vs 15.73+/-3.29 microU/ml) (p<0.001). The difference persisted even after adjustment for weight gain in Group 2 (weight adjusted insulin 11.26+/-3.3 microU/ml; p<0.001). Low birthweight neonates fed fortified breast milk had greater fasting insulin levels compared to those with exclusive breast feeding, at three month of age. The difference persisted after adjustment for excessive gain in fortified milk fed neonates and, suggests adverse glucometabolic programming.

Insulin secretion and insulin resistance in Korean women with gestational diabetes mellitus and impaired glucose tolerance.

PubMed

Yang, Sae Jeong; Kim, Tae Nyun; Baik, Sei Hyun; Kim, Tae Sun; Lee, Kwan Woo; Nam, Moonsuk; Park, Yong Soo; Woo, Jeong-Teak; Kim, Young Seol; Kim, Sung-Hoon

2013-05-01

The aim was to compare the insulin sensitivity and secretion index of pregnant Korean women with normal glucose tolerance (NGT), gestational impaired glucose tolerance (GIGT; only one abnormal value according to the Carpenter and Coustan criteria), and gestational diabetes mellitus (GDM). A cross-sectional study was performed with 1,163 pregnant women with positive (1-hour plasma glucose ≥ 7.2 mmol/L) in a 50-g oral glucose challenge test (OGCT). The 100-g oral glucose tolerance test (OGTT) was used to stratify the participants into three groups: NGT (n = 588), GIGT (n = 294), and GDM (n = 281). The GDM group had higher homeostasis model assessment of insulin resistance and lower insulin sensitivity index (ISOGTT), quantitative insulin sensitivity check index, homeostasis model assessment for estimation of index β-cell secretion (HOMA-B), first and second phase insulin secretion, and insulin secretion-sensitivity index (ISSI) than the NGT group (p ≤ 0.001 for all). Moreover, the GIGT group had lower ISOGTT, HOMA-B, first and second phase insulin secretion, and ISSI than the NGT group (p < 0.001 for all). Among the GIGT subjects, the 1-hour plasma glucose abnormal levels group showed significantly greater weight gain during pregnancy and higher values in the 50-g OGCT than the other two groups. Moreover, the 1-hour and 2-hour abnormal levels groups had poorer insulin secretion status than the 3-hour abnormal levels group. Korean women with GDM show impairments of both insulin secretion and insulin sensitivity. In addition, GIGT is associated with both β-cell dysfunction and insulin resistance.

Astrocytes produce an insulin-like neurotrophic factor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kadle, R.; Suksang, C.; Fellows, R.E.

1986-05-01

They have previously reported that survival of dissociated neurons from fetal rat telencephalon plated at low density in serum-free, hormone-free defined medium is enhanced in the presence of insulin. In the absence of insulin a similar effect on neuronal survival is observed if cells are grown in medium conditioned by glial cells. The present study was carried out to characterize the insulin-like neurotrophic activity present in the glial conditioned medium (GLCM). Conditioned medium from confluent cultures of astrogial cells maintained in a serum free defined medium without insulin was collected every two or three days. A 5 to 30kDa fractionmore » of this medium was obtained by filtering it sequentially through YM30 and YM5 membrane filters. Binding of /sup 125/I-insulin to high density neuronal cultures was inhibited 43% by this fraction. Radioimmunoassay for insulin indicated that 1-2 ng of immuno-reactive insulin were present per ml of GLCM. Immunosequestration of the factor by insulin antibodies bound to protein A agarose gel resulted in loss of neurotrophic activity of the 5 to 30 kDa fraction. These results indicate that cultured astrocytes produce a factor immunologically and biochemically similar to insulin. This factor enhances the survival of neurons in culture and may be important for their normal development and differentiation.« less

Molecular Dynamics Simulations of Insulin: Elucidating the Conformational Changes that Enable Its Binding.

PubMed

Papaioannou, Anastasios; Kuyucak, Serdar; Kuncic, Zdenka

2015-01-01

A sequence of complex conformational changes is required for insulin to bind to the insulin receptor. Recent experimental evidence points to the B chain C-terminal (BC-CT) as the location of these changes in insulin. Here, we present molecular dynamics simulations of insulin that reveal new insights into the structural changes occurring in the BC-CT. We find three key results: 1) The opening of the BC-CT is inherently stochastic and progresses through an open and then a "wide-open" conformation--the wide-open conformation is essential for receptor binding, but occurs only rarely. 2) The BC-CT opens with a zipper-like mechanism, with a hinge at the Phe24 residue, and is maintained in the dominant closed/inactive state by hydrophobic interactions of the neighboring Tyr26, the critical residue where opening of the BC-CT (activation of insulin) is initiated. 3) The mutation Y26N is a potential candidate as a therapeutic insulin analogue. Overall, our results suggest that the binding of insulin to its receptor is a highly dynamic and stochastic process, where initial docking occurs in an open conformation and full binding is facilitated through interactions of insulin receptor residues with insulin in its wide-open conformation.

Metabolism and insulin signaling in common metabolic disorders and inherited insulin resistance.

PubMed

Højlund, Kurt

2014-07-01

Type 2 diabetes, obesity and polycystic ovary syndrome (PCOS) are common metabolic disorders which are observed with increasing prevalences, and which are caused by a complex interplay between genetic and environmental factors, including increased calorie intake and physical inactivity. These metabolic disorders are all characterized by reduced plasma adiponectin and insulin resistance in peripheral tissues. Quantitatively skeletal muscle is the major site of insulin resistance. Both low plasma adiponectin and insulin resistance contribute to an increased risk of type 2 diabetes and cardiovascular disease. In several studies, we have investigated insulin action on glucose and lipid metabolism, and at the molecular level, insulin signaling to glucose transport and glycogen synthesis in skeletal muscle from healthy individuals and in obesity, PCOS and type 2 diabetes. Moreover, we have described a novel syndrome characterized by postprandial hyperinsulinemic hypoglycemia and insulin resistance. This syndrome is caused by a mutation in the tyrosine kinase domain of the insulin receptor gene (INSR). We have studied individuals with this mutation as a model of inherited insulin resistance. Type 2 diabetes, obesity and PCOS are characterized by pronounced defects in the insulin-stimulated glucose uptake, in particular glycogen synthesis and to a lesser extent glucose oxidation, and the ability of insulin to suppress lipid oxidation. In inherited insulin resistance, however, only insulin action on glucose uptake and glycogen synthesis is impaired. This suggests that the defects in glucose and lipid oxidation in the common metabolic disorders are secondary to other factors. In young women with PCOS, the degree of insulin resistance was similar to that seen in middle-aged patients with type 2 diabetes. This supports the hypothesis of an unique pathogenesis of insulin resistance in PCOS. Insulin in physiological concentrations stimulates glucose uptake in human skeletal muscle in vivo by activation of the insulin signaling cascade to glucose transport through the enzymes IRS1, PI3K, Akt2, AS160/TBC1D4 and RAC1, and to glycogen synthesis through Akt2, inhibition of GSK3 and activation of glycogen synthase (GS) via dephosphorylation of serine residues in both the NH2-terminal (site 2+2a) and the COOH-terminal end (site 3a+3b). In type 2 diabetes, obesity and PCOS, there is, although with some variation from study to study, defects in insulin signaling through IRS1, PI3K, Akt2 and AS160/TBC1D4, which can explain reduced insulin action on glucose transport. In type 2 diabetes an altered intracellular distribution of SNAP23 and impaired activation of RAC1 also seem to play a role for reduced insulin action on glucose transport. In all common metabolic disorders, we observed an impaired insulin activation of GS, which seems to be caused by attenuated dephosphorylation of GS at site 2+2a, whereas as the inhibition of GSK3 and the dephosphorylation of GS at its target sites, site 3a+3a, appeared to be completely normal. In individuals with inherited insulin resistance, we observed largely the same defects in insulin action on IRS1, PI3K, Akt2 and GS, as well as a normal inhibition of GSK3 and dephosphorylation of GS at site 3a+3b. In these individuals, however, a markedly reduced insulin clearance seems to partially rescue insulin signaling to glucose transport and GS. Adiponectin is thought to improve insulin sensitivity primarily by increasing lipid oxidation through activation of the enzyme AMPK, and possibly via cross-talking of adiponectin with insulin signaling, and hence glucose transport and glycogen synthesis. We demonstrated a strong correlation between plasma adiponectin and insulin action on glucose disposal and glycogen synthesis in obesity, type 2 diabetes and PCOS. In individuals with inherited insulin resistance, plasma adiponectin was normal, but the correlation of adiponectin with insulin-stimulated glucose uptake and glycogen synthesis was at least equally strong. Moreover, we found a correlation between plasma adiponectin and insulin activation of GS. This result is supported by a number of recent studies of animal models and muscle cell lines, which have shown that adiponectin augments insulin action on enzymes in the insulin signaling cascade. In contrast, we observed no differences in the abundance or activity of AMPK in obesity, type 2 diabetes, PCOS or inherited insulin resistance. This indicates that reduced insulin sensitivity in these conditions is not mediated via abnormal AMPK activity. The results from these studies demonstrate that the well-established abnormalities in insulin action on glucose uptake and glycogen synthesis are reflected by defects in insulin signaling to these cellular processes in type 2 diabetes, obesity, and PCOS, and as expected also in inherited insulin resistance caused by a mutation in INSR. In common metabolic disorders, low plasma adiponectin may contribute to insulin resistance and defects in insulin signaling, whereas in inherited insulin resistance a normal plasma adiponectin and reduced insulin clearance could contribute to maintain a sufficient activation of the insulin signaling cascade. The insight gained from these studies have improved our understanding of the molecular mechanisms underlying insulin resistance in skeletal muscle of humans, and can form the basis for further studies, which can lead to the development of treatment that more directly targets insulin resistance, and hence reduce the risk of type 2 diabetes and cardiovascular disease.

E4orf1 induction in adipose tissue promotes insulin-independent signaling in the adipocyte.

PubMed

Kusminski, Christine M; Gallardo-Montejano, Violeta I; Wang, Zhao V; Hegde, Vijay; Bickel, Perry E; Dhurandhar, Nikhil V; Scherer, Philipp E

2015-10-01

Type 2 diabetes remains a worldwide epidemic with major pathophysiological changes as a result of chronic insulin resistance. Insulin regulates numerous biochemical pathways related to carbohydrate and lipid metabolism. We have generated a novel mouse model that allows us to constitutively activate, in an inducible fashion, the distal branch of the insulin signaling transduction pathway specifically in adipocytes. Using the adenoviral 36 E4orf1 protein, we chronically stimulate locally the Ras-ERK-MAPK signaling pathway. At the whole body level, this leads to reduced body-weight gain under a high fat diet challenge. Despite overlapping glucose tolerance curves, there is a reduced requirement for insulin action under these conditions. The mice further exhibit reduced circulating adiponectin levels that ultimately lead to impaired lipid clearance, and inflamed and fibrotic white adipose tissues. Nevertheless, they are protected from diet-induced hepatic steatosis. As we observe constitutively elevated p-Akt levels in the adipocytes, even under conditions of low insulin levels, this pinpoints enhanced Ras-ERK-MAPK signaling in transgenic adipocytes as a potential alternative route to bypass proximal insulin signaling events. We conclude that E4orf1 expression in the adipocyte leads to enhanced baseline activation of the distal insulin signaling node, yet impaired insulin receptor stimulation in the presence of insulin, with important implications for the regulation of adiponectin secretion. The resulting systemic phenotype is complex, yet highlights the powerful nature of manipulating selective branches of the insulin signaling network within the adipocyte.

Effect of a High-Fructose Weight-Maintaining Diet on Lipogenesis and Liver Fat

PubMed Central

Noworolski, Susan M.; Wen, Michael J.; Dyachenko, Artem; Prior, Jessica L.; Weinberg, Melissa E.; Herraiz, Laurie A.; Tai, Viva W.; Bergeron, Nathalie; Bersot, Thomas P.; Rao, Madhu N.; Schambelan, Morris; Mulligan, Kathleen

2015-01-01

Context: Consumption of high-fructose diets promotes hepatic fatty acid synthesis (de novo lipogenesis [DNL]) and an atherogenic lipid profile. It is unclear whether these effects occur independent of positive energy balance and weight gain. Objectives: We compared the effects of a high-fructose, (25% of energy content) weight-maintaining diet to those of an isocaloric diet with the same macronutrient distribution but in which complex carbohydrate (CCHO) was substituted for fructose. Design, Setting, and Participants: Eight healthy men were studied as inpatients for consecutive 9-day periods. Stable isotope tracers were used to measure fractional hepatic DNL and endogenous glucose production (EGP) and its suppression during a euglycemic-hyperinsulinemic clamp. Liver fat was measured by magnetic resonance spectroscopy. Results: Weight remained stable. Regardless of the order in which the diets were fed, the high-fructose diet was associated with both higher DNL (average, 18.6 ± 1.4% vs 11.0 ± 1.4% for CCHO; P = .001) and higher liver fat (median, +137% of CCHO; P = .016) in all participants. Fasting EGP and insulin-mediated glucose disposal did not differ significantly, but EGP during hyperinsulinemia was greater (0.60 ± 0.07 vs 0.46 ± 0.06 mg/kg/min; P = .013) with the high-fructose diet, suggesting blunted suppression of EGP. Conclusion: Short-term high-fructose intake was associated with increased DNL and liver fat in healthy men fed weight-maintaining diets. PMID:25825943

Effects of agave nectar versus sucrose on weight gain, adiposity, blood glucose, insulin, and lipid responses in mice.

PubMed

Hooshmand, Shirin; Holloway, Brittany; Nemoseck, Tricia; Cole, Sarah; Petrisko, Yumi; Hong, Mee Young; Kern, Mark

2014-09-01

Agave nectar is a fructose-rich liquid sweetener derived from a plant, and is often promoted as a low glycemic alternative to refined sugar. However, little scientific research has been conducted in animals or humans to determine its metabolic and/or health effects. The aim of this study was to explore the influence of agave nectar versus sucrose on weight gain, adiposity, fasting plasma blood glucose, insulin, and lipid levels. Eighteen (n=18) male ICR mice (33.8±1.6 g) were divided into two groups (n=6 for agave nectar and n=12 for sucrose) and provided free access to one of two diets of equal energy densities differing only in a portion of the carbohydrate provided. Diets contained 20% carbohydrate (by weight of total diet) from either raw agave nectar or sucrose. Epididymal fat pads were excised, and blood was collected after 34 days. Weight gain (4.3±2.2 vs. 8.4±3.4 g), fat pad weights (0.95±0.54 vs. 1.75±0.66 g), plasma glucose (77.8±12.2 vs. 111.0±27.9 mg/dL), and insulin (0.61±0.29 vs. 1.46±0.81 ng/mL) were significantly lower (P≤.05) for agave nectar-fed mice compared to sucrose-fed mice respectively. No statistically significant differences in total cholesterol or triglycerides were detected. These results suggest that in comparison to sucrose, agave nectar may have a positive influence on weight gain and glucose control. However, more research with a larger sample of animals and/or with human subjects is warranted.

Cost-effectiveness analysis of IDegLira versus basal-bolus insulin for patients with type 2 diabetes in the Slovak health system

PubMed Central

Psota, Marek; Psenkova, Maria Bucek; Racekova, Natalia; Ramirez de Arellano, Antonio; Vandebrouck, Tom; Hunt, Barnaby

2017-01-01

Aims To investigate the cost-effectiveness of once-daily insulin degludec/liraglutide (IDegLira) versus basal-bolus therapy in patients with type 2 diabetes not meeting glycemic targets on basal insulin from a healthcare payer perspective in Slovakia. Methods Long-term clinical and economic outcomes for patients receiving IDegLira and basal-bolus therapy were estimated using the IMS CORE Diabetes Model based on a published pooled analysis of patient-level data. Results IDegLira was associated with an improvement in quality-adjusted life expectancy of 0.29 quality-adjusted life years (QALYs) compared with basal-bolus therapy. The average lifetime cost per patient in the IDegLira arm was EUR 2,449 higher than in the basal-bolus therapy arm. Increased treatment costs with IDegLira were partially offset by cost savings from avoided diabetes-related complications. IDegLira was highly cost-effective versus basal-bolus therapy with an incremental cost-effectiveness ratio of EUR 8,590 per QALY gained, which is well below the cost-effectiveness threshold set by the law in Slovakia. Conclusion IDegLira is cost-effective in Slovakia, providing a simple option for intensification of basal insulin therapy without increasing the risk of hypoglycemia or weight gain and with fewer daily injections than a basal-bolus regimen. PMID:29276398

Consumption of clarified grapefruit juice ameliorates high-fat diet induced insulin resistance and weight gain in mice.

PubMed

Chudnovskiy, Rostislav; Thompson, Airlia; Tharp, Kevin; Hellerstein, Marc; Napoli, Joseph L; Stahl, Andreas

2014-01-01

To determine the metabolic effects of grapefruit juice consumption we established a model in which C57Bl/6 mice drank 25-50% sweetened GFJ, clarified of larger insoluble particles by centrifugation (cGFJ), ad libitum as their sole source of liquid or isocaloric and sweetened water. cGFJ and control groups consumed similar amounts of liquids and calories. Mice fed a high-fat diet and cGFJ experienced a 18.4% decrease in weight, a 13-17% decrease in fasting blood glucose, a three-fold decrease in fasting serum insulin, and a 38% decrease in liver triacylglycerol values, compared to controls. Mice fed a low-fat diet that drank cGFJ experienced a two-fold decrease in fasting insulin, but not the other outcomes observed with the high-fat diet. cGFJ consumption decreased blood glucose to a similar extent as the commonly used anti-diabetic drug metformin. Introduction of cGFJ after onset of diet-induced obesity also reduced weight and blood glucose. A bioactive compound in cGFJ, naringin, reduced blood glucose and improved insulin tolerance, but did not ameliorate weight gain. These data from a well-controlled animal study indicate that GFJ contains more than one health-promoting neutraceutical, and warrant further studies of GFJ effects in the context of obesity and/or the western diet.

Metabolic markers during pregnancy and their association with maternal and newborn weight status.

PubMed

Perichart-Perera, Otilia; Muñoz-Manrique, Cinthya; Reyes-López, Angélica; Tolentino-Dolores, Maricruz; Espino Y Sosa, Salvador; Ramírez-González, Ma Cristina

2017-01-01

Obesity during pregnancy increases the risk of adverse clinical outcomes and is associated with low-grade chronic inflammation. We describe maternal metabolic risk and inflammation by maternal weight status, and evaluate the association of metabolic and inflammatory markers with birthweight in a group of pregnant Mexican women. This study derived from a prospective cohort of healthy pregnant women <14 weeks of gestation, receiving prenatal care at National Institute of Perinatology (Mexico, 2009-2013). Metabolic and inflammatory markers were measured in maternal serum in all three pregnancy trimesters (1st: 11.42±1.7; 2nd: 21.06±2.4; 3rd: 32.74±2.3 weeks). Pregestational weight was self-reported, and body mass index (BMI) was calculated. Gestational weight gain was evaluated in the third trimester. Newborn´s weight was measured at birth. We carried out correlations, general mixed linear model and regression analyses, based on pregestational weight (self-reported), body mass index (BMI), gestational weight gain (evaluated in the third trimester) and newborn weight (measured at birth). Of the 177 women included in the study (mean age = 26.93±8.49), thirty-eight percent (n = 67) were overweight or had obesity, and 32.8% (n = 58) showed excessive gestational weight gain. We found insulin, lipids (including total cholesterol, LDL-cholesterol, HDL-cholesterol, and triglycerides-TG), leptin and interleukin 1b (IL-1b) all increased significantly (p<0.05) during pregnancy. Pregestational maternal weight status altered longitudinal concentrations of insulin, leptin, adiponectin, TG and C reactive protein. Excessive gestational weight gain was associated with higher maternal insulin in the third trimester (p<0.05). Early pregnancy leptin and TNFα were determinants of birthweight in women with normal weight, but not in overweight or obese women. Maternal weight status affected the concentrations of insulin, leptin, adiponectin, triglycerides and C reactive protein throughout pregnancy. The role of early leptin and TNFα in fetal growth need further study given the association was only observed in normal weight women. This study presents data distribution of metabolic and inflammatory markers of normal weight and overweight/obese women that did not develop GDM, preeclampsia nor macrosomia.

Reversal of the toxic effects of cachectin by concurrent insulin administration.

PubMed

Fraker, D L; Merino, M J; Norton, J A

1989-06-01

Rats treated with recombinant human tumor necrosis factor-cachectin, 100 micrograms/kg ip twice daily for 5 consecutive days, had a 56% decrease in food intake, a 54% decrease in nitrogen balance, and a 23-g decrease in body weight gain vs. saline-treated controls. Concurrent neutral protamine hagedorn insulin administration of 2 U/100 g sc twice daily reversed all of these changes to control levels without causing any treatment deaths. The improvement seen with insulin was dose independent. Five days of cachectin treatment caused a severe interstitial pneumonitis, periportal inflammation in the liver, and an increase in wet organ weight in the heart, lungs, kidney, and spleen. Concurrent insulin treatment led to near total reversal of these histopathologic changes. Cachectin treatment did not significantly change blood glucose levels from control values of 130-140 mg/dl, but insulin plus cachectin caused a significant decrease in blood glucose from 1 through 12 h after injection. Administration of high-dose insulin can near totally reverse the nutritional and histopathologic toxicity of sublethal doses of cachectin in rats.

A Branched-Chain Amino Acid-Related Metabolic Signature that Differentiates Obese and Lean Humans and Contributes to Insulin Resistance

PubMed Central

Newgard, Christopher B; An, Jie; Bain, James R; Muehlbauer, Michael J; Stevens, Robert D; Lien, Lillian F; Haqq, Andrea M; Shah, Svati H.; Arlotto, Michelle; Slentz, Cris A; Rochon, James; Gallup, Dianne; Ilkayeva, Olga; Wenner, Brett R; Yancy, William E; Eisenson, Howard; Musante, Gerald; Surwit, Richard; Millington, David S; Butler, Mark D; Svetkey, Laura P

2009-01-01

Summary Metabolomic profiling of obese versus lean humans reveals a branched-chain amino acid (BCAA)-related metabolite signature that is suggestive of increased catabolism of BCAA and correlated with insulin resistance. To test its impact on metabolic homeostasis, we fed rats on high-fat (HF), HF with supplemented BCAA (HF/BCAA) or standard chow (SC) diets. Despite having reduced food intake and weight gain equivalent to the SC group, HF/BCAA rats were equally insulin resistant as HF rats. Pair-feeding of HF diet to match the HF/BCAA animals or BCAA addition to SC diet did not cause insulin resistance. Insulin resistance induced by HF/BCAA feeding was accompanied by chronic phosphorylation of mTOR, JNK, and IRS1(ser307), accumulation of multiple acylcarnitines in muscle, and was reversed by the mTOR inhibitor, rapamycin. Our findings show that in the context of a poor dietary pattern that includes high fat consumption, BCAA contributes to development of obesity-associated insulin resistance. PMID:19356713

A Review of the “Bolus Guide,” A New Insulin Bolus Dosing Support Tool Based on Selection of Carbohydrate Ranges

PubMed Central

Pańkowska, Ewa

2010-01-01

In this issue of Journal of Diabetes Science and Technology, Shapira and colleagues present new concepts of carbohydrate load estimation in intensive insulin therapy. By using a mathematical model, they attempt to establish how accurately carbohydrate food content should be maintained in order to keep postprandial blood glucose levels in the recommended range. Their mathematical formula, the “bolus guide” (BG), is verified by simulating prandial insulin dosing and responding to proper blood glucose levels. Different variants such as insulin sensitivity factor, insulin-to-carbohydrate ratio, and target blood glucose were taken into this formula in establishing the calculated proper insulin dose. The new approach presented here estimates the carbohydrate content by rearranging the carbohydrate load instead of the simple point estimation that the current bolus calculators (BCs) use. Computerized estimations show that the BG directives, as compared to a BC, result in more glucose levels above 200 mg/dl and thus indicate less hypoglycemia readings. PMID:20663454

Green Synthesis of Oxovanadium(IV)/chitosan Nanocomposites and Its Ameliorative Effect on Hyperglycemia, Insulin Resistance, and Oxidative Stress.

PubMed

Liu, Yanjun; Jie, Xu; Guo, Yongli; Zhang, Xin; Wang, Jingfeng; Xue, Changhu

2016-02-01

In this paper, the preparation, characterization, and ameliorative effect on high-fat high-sucrose diet-induced hyperglycemia, insulin resistance, oxidative stress in mice of novel oxovanadium(IV)/chitosan (OV/CS) nanocomposites were investigated. The nanobiocomposite was produced by chemical reduction by chitosan and L-ascorbic acid using microwave heating, under environment-friendly conditions, using aqueous solutions, and notably, by using both mediators as reducing and stabilizing agents. In addition, OV/CS nanocomposites were characterized by transmission electron microscopy, energy dispersive spectroscopy, particle size, and zeta potential measurements. In vivo experiments were designed to examine whether the OV/CS nanocomposites would provide additional benefits on oxidative stress, hyperglycemia, and insulin resistance in mice with type 2 diabetes. The results rendered insulin resistant by treating with OV/CS nanocomposites alleviate insulin resistance and improve oxidative stress. Such nanocomposite seem to be a valuable therapy to achieve and/or maintain glycemic control and therapeutic agents in the treatment arsenal for insulin resistance and type 2 diabetes.

A critical role for beta cell M3 muscarinic acetylcholine receptors in regulating insulin release and blood glucose homeostasis in vivo.

PubMed

Gautam, Dinesh; Han, Sung-Jun; Hamdan, Fadi F; Jeon, Jongrye; Li, Bo; Li, Jian Hua; Cui, Yinghong; Mears, David; Lu, Huiyan; Deng, Chuxia; Heard, Thomas; Wess, Jürgen

2006-06-01

One of the hallmarks of type 2 diabetes is that pancreatic beta cells fail to release sufficient amounts of insulin in the presence of elevated blood glucose levels. Insulin secretion is modulated by many hormones and neurotransmitters including acetylcholine, the major neurotransmitter of the peripheral parasympathetic nervous system. The physiological role of muscarinic acetylcholine receptors expressed by pancreatic beta cells remains unclear at present. Here, we demonstrate that mutant mice selectively lacking the M3 muscarinic acetylcholine receptor subtype in pancreatic beta cells display impaired glucose tolerance and greatly reduced insulin release. In contrast, transgenic mice selectively overexpressing M3 receptors in pancreatic beta cells show a profound increase in glucose tolerance and insulin release. Moreover, these mutant mice are resistant to diet-induced glucose intolerance and hyperglycemia. These findings indicate that beta cell M3 muscarinic receptors play a key role in maintaining proper insulin release and glucose homeostasis.

Fanconi anemia links reactive oxygen species to insulin resistance and obesity.

PubMed

Li, Jie; Sipple, Jared; Maynard, Suzette; Mehta, Parinda A; Rose, Susan R; Davies, Stella M; Pang, Qishen

2012-10-15

Insulin resistance is a hallmark of obesity and type 2 diabetes. Reactive oxygen species (ROS) have been proposed to play a causal role in insulin resistance. However, evidence linking ROS to insulin resistance in disease settings has been scant. Since both oxidative stress and diabetes have been observed in patients with the Fanconi anemia (FA), we sought to investigate the link between ROS and insulin resistance in this unique disease model. Mice deficient for the Fanconi anemia complementation group A (Fanca) or Fanconi anemia complementation group C (Fancc) gene seem to be diabetes-prone, as manifested by significant hyperglycemia and hyperinsulinemia, and rapid weight gain when fed with a high-fat diet. These phenotypic features of insulin resistance are characterized by two critical events in insulin signaling: a reduction in tyrosine phosphorylation of the insulin receptor (IR) and an increase in inhibitory serine phosphorylation of the IR substrate-1 in the liver, muscle, and fat tissues from the insulin-challenged FA mice. High levels of ROS, spontaneously accumulated or generated by tumor necrosis factor alpha in these insulin-sensitive tissues of FA mice, were shown to underlie the FA insulin resistance. Treatment of FA mice with the natural anti-oxidant Quercetin restores IR signaling and ameliorates the diabetes- and obesity-prone phenotypes. Finally, pairwise screen identifies protein-tyrosine phosphatase (PTP)-α and stress kinase double-stranded RNA-dependent protein kinase (PKR) that mediate the ROS effect on FA insulin resistance. These findings establish a pathogenic and mechanistic link between ROS and insulin resistance in a unique human disease setting. ROS accumulation contributes to the insulin resistance in FA deficiency by targeting both PTP-α and PKR.

Fanconi Anemia Links Reactive Oxygen Species to Insulin Resistance and Obesity

PubMed Central

Li, Jie; Sipple, Jared; Maynard, Suzette; Mehta, Parinda A.; Rose, Susan R.; Davies, Stella M.

2012-01-01

Abstract Aims: Insulin resistance is a hallmark of obesity and type 2 diabetes. Reactive oxygen species (ROS) have been proposed to play a causal role in insulin resistance. However, evidence linking ROS to insulin resistance in disease settings has been scant. Since both oxidative stress and diabetes have been observed in patients with the Fanconi anemia (FA), we sought to investigate the link between ROS and insulin resistance in this unique disease model. Results: Mice deficient for the Fanconi anemia complementation group A (Fanca) or Fanconi anemia complementation group C (Fancc) gene seem to be diabetes-prone, as manifested by significant hyperglycemia and hyperinsulinemia, and rapid weight gain when fed with a high-fat diet. These phenotypic features of insulin resistance are characterized by two critical events in insulin signaling: a reduction in tyrosine phosphorylation of the insulin receptor (IR) and an increase in inhibitory serine phosphorylation of the IR substrate-1 in the liver, muscle, and fat tissues from the insulin-challenged FA mice. High levels of ROS, spontaneously accumulated or generated by tumor necrosis factor alpha in these insulin-sensitive tissues of FA mice, were shown to underlie the FA insulin resistance. Treatment of FA mice with the natural anti-oxidant Quercetin restores IR signaling and ameliorates the diabetes- and obesity-prone phenotypes. Finally, pairwise screen identifies protein-tyrosine phosphatase (PTP)-α and stress kinase double-stranded RNA-dependent protein kinase (PKR) that mediate the ROS effect on FA insulin resistance. Innovation: These findings establish a pathogenic and mechanistic link between ROS and insulin resistance in a unique human disease setting. Conclusion: ROS accumulation contributes to the insulin resistance in FA deficiency by targeting both PTP-α and PKR. Antioxid. Redox Signal. 00, 000–000. PMID:22482891

[Pancreatic infringement exocrine and endocrine in cystic fibrosis].

PubMed

Kessler, L; Abély, M

2016-12-01

The exocrine pancreatic insufficiency affects more than 80% of cystic fibrosis (CF) infants. Pancreatic insufficiency is diagnosed by low levels of fecal elastase. An optimal caloric intake, a pancreatic enzyme treatment are the keys to maintain a good nutritional status. The fat soluble vitamins supplementation will be associated with pancreatic enzymes treatment and will be adapted to plasma levels. Iron and oligo-element deficiency such as zinc is common. The pancreatic enzymes function is not optimal in the proximal bowel: the intraluminal intestinal pH is low because of the absence of bicarbonate release by the pancreas. The use of proton pump inhibitors may improve the functionality of pancreatic enzymes treatment. New therapies such as ivacaftor in patients with a G551D mutation allows a weight gain in particular by restoring intestinal pH similar to controls. Lengthening of the life expectancy of patients with CF is accompanied by the emergence new aspects of the disease, especially diabetes, favored by pancreatic cystic fibrosis resulting in an anatomical destruction of pancreatic islets. Currently, diabetes affects a third of the patients after 20 years, and half after 30 years. Cystic fibrosis-related diabetes is a major factor of morbidity-mortality in all stages of the disease and is characterized by a preclinical phase of glucose intolerance particularly long reaching up to 10 years. Its pathophysiology combines a lack of insulin secretion, an insulin resistance secondary to chronic infection, and a decrease in the production of the GIP and GLP-1. The insulin secretion depending on the channel chlorine (Cystic Fibrosis Transmembrane conductance Regulator [CFTR]) activity at the membrane surface of insulin cell is reduced prior to the occurrence of pancreatic histological lesions. At the stage of diabetes, obtaining a normoglycemia by insulin treatment began very early allows to slow the decline of lung function and nutritional status. Given the silent phase of diabetes, screening it is recommended by the realization of an annual OGTT from 10 years of age, or before in severe forms of CF. New treatments of CF able to target CFTR showed their efficacy in slowing the decline of lung function, and could also contribute to slow or prevent the onset of diabetes. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Comparative Study of Serum Leptin and Insulin Resistance Levels Between Korean Postmenopausal Vegetarian and Non-vegetarian Women.

PubMed

Kim, Mi-Hyun; Bae, Yun-Jung

2015-07-01

The present study was conducted to compare serum leptin and insulin resistance levels between Korean postmenopausal long-term semi-vegetarians and non-vegetarians. Subjects of this study belonged to either a group of postmenopausal vegetarian women (n = 54), who maintained a semi-vegetarian diet for over 20 years or a group of non-vegetarian controls. Anthropometric characteristics, serum leptin, serum glucose, serum insulin, insulin resistance (HOMA-IR; Homeostasis Model Assessment of Insulin Resistance), and nutrient intake were compared between the two groups. The vegetarians showed significantly lower body weight (p < 0.01), body mass index (p < 0.001), percentage (%) of body fat (p < 0.001), and serum levels of leptin (p < 0.05), glucose (p < 0.001), and insulin (p < 0.01), than the non-vegetarians. The HOMA-IR of the vegetarians was significantly lower than that of the non-vegetarians (p < 0.01) after adjustment for the % of body fat. A long-term vegetarian diet might be related to lower insulin resistance independent of the % of body fat in postmenopausal women.

Comparative Study of Serum Leptin and Insulin Resistance Levels Between Korean Postmenopausal Vegetarian and Non-vegetarian Women

PubMed Central

Kim, Mi-Hyun

2015-01-01

The present study was conducted to compare serum leptin and insulin resistance levels between Korean postmenopausal long-term semi-vegetarians and non-vegetarians. Subjects of this study belonged to either a group of postmenopausal vegetarian women (n = 54), who maintained a semi-vegetarian diet for over 20 years or a group of non-vegetarian controls. Anthropometric characteristics, serum leptin, serum glucose, serum insulin, insulin resistance (HOMA-IR; Homeostasis Model Assessment of Insulin Resistance), and nutrient intake were compared between the two groups. The vegetarians showed significantly lower body weight (p < 0.01), body mass index (p < 0.001), percentage (%) of body fat (p < 0.001), and serum levels of leptin (p < 0.05), glucose (p < 0.001), and insulin (p < 0.01), than the non-vegetarians. The HOMA-IR of the vegetarians was significantly lower than that of the non-vegetarians (p < 0.01) after adjustment for the % of body fat. A long-term vegetarian diet might be related to lower insulin resistance independent of the % of body fat in postmenopausal women. PMID:26251836

Role of ghrelin and leptin in the regulation of carbohydrate metabolism. Part II. Leptin.

PubMed

Otto-Buczkowska, Ewa; Chobot, Agata

2012-10-26

Leptin is produced by mature adipocytes. Its amount correlates positively with the mass of the adipose tissue. Leptin plays a crucial role in maintaining body weight and glucose homeostasis. It is transported through the blood-brain barrier to the central nervous system, where it activates the autonomic nervous system, causing the feeling of satiety and inhibiting appetite. It also acts through central and peripheral pathways, including the regulation of insulin secretion by pancreatic β cells. Leptin may also directly affect the metabolism and function of peripheral tissues. It has been found to play a role in peripheral insulin resistance by attenuating insulin action, and perhaps also insulin signaling, in various insulin-responsive cell types. Recent data provide convincing evidence that leptin has a beneficial influence on glucose homeostasis. Studies suggest that leptin could be used as an adjunct of insulin therapy in insulin-deficient diabetes, thereby providing an insight into the therapeutic implications of leptin as an anti-diabetic agent. Extensive research will be needed to determine long-term safety and efficacy of such a therapy.

Identification of fatty acid binding protein 4 as an adipokine that regulates insulin secretion during obesity

PubMed Central

Wu, Lindsay E.; Samocha-Bonet, Dorit; Whitworth, P. Tess; Fazakerley, Daniel J.; Turner, Nigel; Biden, Trevor J.; James, David E.; Cantley, James

2014-01-01

A critical feature of obesity is enhanced insulin secretion from pancreatic β-cells, enabling the majority of individuals to maintain glycaemic control despite adiposity and insulin resistance. Surprisingly, the factors coordinating this adaptive β-cell response with adiposity have not been delineated. Here we show that fatty acid binding protein 4 (FABP4/aP2) is an adipokine released from adipocytes under obesogenic conditions, such as hypoxia, to augment insulin secretion. The insulinotropic action of FABP4 was identified using an in vitro system that recapitulates adipocyte to β-cell endocrine signalling, with glucose-stimulated insulin secretion (GSIS) as a functional readout, coupled with quantitative proteomics. Exogenous FABP4 potentiated GSIS in vitro and in vivo, and circulating FABP4 levels correlated with GSIS in humans. Insulin inhibited FABP4 release from adipocytes in vitro, in mice and in humans, consistent with feedback regulation. These data suggest that FABP4 and insulin form an endocrine loop coordinating the β-cell response to obesity. PMID:24944906

RBP4 activates antigen-presenting cells leading to adipose tissue inflammation and systemic insulin resistance

PubMed Central

Moraes-Vieira, Pedro M.; Yore, Mark M.; Dwyer, Peter M.; Syed, Ismail; Aryal, Pratik; Kahn, Barbara B.

2014-01-01

Insulin resistance is a major cause of diabetes and is highly associated with adipose tissue (AT) inflammation in obesity. RBP4, a retinol-transporter, is elevated in insulin resistance and contributes to increased diabetes risk. We aimed to determine the mechanisms for RBP4-induced insulin resistance. Here we show that RBP4 elevation causes AT inflammation by activating innate immunity which elicits an adaptive immune-response. RBP4-overexpressing mice (RBP4-Ox) are insulin-resistant and glucose-intolerant and have increased AT macrophage and CD4 T-cell infiltration. In RBP4-Ox, AT CD206+ macrophages express pro-inflammatory markers and activate CD4 T-cells while maintaining alternatively-activated macrophage markers. These effects result from direct activation of AT antigen-presenting cells (APCs) by RBP4 through a JNK-dependent pathway. Transfer of RBP4-activated APCs into normal mice is sufficient to induce AT inflammation, insulin resistance and glucose intolerance. Thus, RBP4 causes insulin resistance, at least partly, by activating AT APCs which induce CD4 T-cell Th1 polarization and AT inflammation. PMID:24606904

Conformational Dynamics of Insulin

PubMed Central

Hua, Qing-Xin; Jia, Wenhua; Weiss, Michael A.

2011-01-01

We have exploited a prandial insulin analog to elucidate the underlying structure and dynamics of insulin as a monomer in solution. A model was provided by insulin lispro (the active component of Humalog®; Eli Lilly and Co.). Whereas NMR-based modeling recapitulated structural relationships of insulin crystals (T-state protomers), dynamic anomalies were revealed by amide-proton exchange kinetics in D2O. Surprisingly, the majority of hydrogen bonds observed in crystal structures are only transiently maintained in solution, including key T-state-specific inter-chain contacts. Long-lived hydrogen bonds (as defined by global exchange kinetics) exist only at a subset of four α-helical sites (two per chain) flanking an internal disulfide bridge (cystine A20–B19); these sites map within the proposed folding nucleus of proinsulin. The anomalous flexibility of insulin otherwise spans its active surface and may facilitate receptor binding. Because conformational fluctuations promote the degradation of pharmaceutical formulations, we envisage that “dynamic re-engineering” of insulin may enable design of ultra-stable formulations for humanitarian use in the developing world. PMID:22649374

Alteration in mitochondrial Ca(2+) uptake disrupts insulin signaling in hypertrophic cardiomyocytes.

PubMed

Gutiérrez, Tomás; Parra, Valentina; Troncoso, Rodrigo; Pennanen, Christian; Contreras-Ferrat, Ariel; Vasquez-Trincado, César; Morales, Pablo E; Lopez-Crisosto, Camila; Sotomayor-Flores, Cristian; Chiong, Mario; Rothermel, Beverly A; Lavandero, Sergio

2014-11-07

Cardiac hypertrophy is characterized by alterations in both cardiac bioenergetics and insulin sensitivity. Insulin promotes glucose uptake by cardiomyocytes and its use as a substrate for glycolysis and mitochondrial oxidation in order to maintain the high cardiac energy demands. Insulin stimulates Ca(2+) release from the endoplasmic reticulum, however, how this translates to changes in mitochondrial metabolism in either healthy or hypertrophic cardiomyocytes is not fully understood. In the present study we investigated insulin-dependent mitochondrial Ca(2+) signaling in normal and norepinephrine or insulin like growth factor-1-induced hypertrophic cardiomyocytes. Using mitochondrion-selective Ca(2+)-fluorescent probes we showed that insulin increases mitochondrial Ca(2+) levels. This signal was inhibited by the pharmacological blockade of either the inositol 1,4,5-triphosphate receptor or the mitochondrial Ca(2+) uniporter, as well as by siRNA-dependent mitochondrial Ca(2+) uniporter knockdown. Norepinephrine-stimulated cardiomyocytes showed a significant decrease in endoplasmic reticulum-mitochondrial contacts compared to either control or insulin like growth factor-1-stimulated cells. This resulted in a reduction in mitochondrial Ca(2+) uptake, Akt activation, glucose uptake and oxygen consumption in response to insulin. Blocking mitochondrial Ca(2+) uptake was sufficient to mimic the effect of norepinephrine-induced cardiomyocyte hypertrophy on insulin signaling. Mitochondrial Ca(2+) uptake is a key event in insulin signaling and metabolism in cardiomyocytes.

Enhanced insulin sensitivity in prepubertal children with constitutional delay of growth and development.

PubMed

Wilson, Dyanne A; Hofman, Paul L; Miles, Harriet L; Sato, Tim A; Billett, Nathalie E; Robinson, Elizabeth M; Cutfield, Wayne S

2010-02-01

To test the hypothesis that prepubertal children with presumed constitutional delay of growth and development (CDGD) have enhanced insulin sensitivity and, therefore, insulin sensitivity is associated with later onset of puberty. Twenty-one prepubertal children with presumed CDGD and 23 prepubertal control children, underwent a frequently sampled intravenous glucose tolerance test to evaluate insulin sensitivity and other markers of insulin, glucose, and growth regulation. Children in the CDGD group were shorter and leaner than control subjects. Children with presumed CDGD were 40% more insulin sensitive (17.0 x 10(-4) min(-1)/[mU/L] versus 12.1 x 10(-4) min(-1)/[mU/L]; P = .0006) and had reduced acute insulin response, thus maintaining euglycemia (216 mU/L versus 330 mU/L; P = .02) compared with control subjects. In addition, the CDGD group had lower serum insulin-like growth factor binding protein 3 levels (3333 ng/mL versus 3775 ng/mL; P = .0004) and a trend toward lower serum insulin-like growth factor-II levels (794 ng/mL versus 911 ng/mL; P = .06). Prepubertal children with presumed CDGD have enhanced insulin sensitivity, supporting the hypothesis that insulin sensitivity is associated with timing of puberty. It may signify long-term biological advantages with lower risk of metabolic syndrome and malignancy. Copyright 2010 Mosby, Inc. All rights reserved.

Improved Pharmacokinetic and Pharmacodynamic Profile of Rapid-Acting Insulin Using Needle-Free Jet Injection Technology

PubMed Central

Engwerda, Elsemiek E.C.; Abbink, Evertine J.; Tack, Cees J.; de Galan, Bastiaan E.

2011-01-01

OBJECTIVE Insulin administered by jet injectors is dispensed over a larger subcutaneous area than insulin injected with a syringe, which may facilitate a more rapid absorption. This study compared the pharmacologic profile of administration of insulin aspart by jet injection to that by conventional insulin pen. RESEARCH DESIGN AND METHODS Euglycemic glucose clamp tests were performed in 18 healthy volunteers after subcutaneous administration of 0.2 units/kg body wt of aspart, either administered by jet injection or by conventional pen, using a randomized, double-blind, double-dummy, cross over study design. Pharmacodynamic and pharmacokinetic profiles were derived from the glucose infusion rate (GIR) needed to maintain euglycemia and from plasma insulin levels, respectively. RESULTS The time to maximal GIR was significantly shorter when insulin was injected with the jet injector compared with conventional pen administration (51 ± 3 vs. 105 ± 11 min, P < 0.0001). The time to peak insulin concentration was similarly reduced (31 ± 3 vs. 64 ± 6 min, P < 0.0001) and peak insulin concentrations were increased (108 ± 13 vs. 79 ± 7 mU/L, P = 0.01) when insulin was injected by jet injection compared with conventional pen injection. Jet injector insulin administration reduced the time to 50% glucose disposal by ∼40 min (P < 0.0001). There were no differences in maximal GIR, total insulin absorption, or total insulin action between the two devices. CONCLUSIONS Administration of insulin aspart by jet injection enhances insulin absorption and reduces the duration of glucose-lowering action. This profile resembles more closely the pattern of endogenous insulin secretion and may help to achieve better meal insulin coverage and correction of postprandial glucose excursions. PMID:21715522

Fructose intervention for 12 weeks does not impair glycemic control or incretin hormone responses during oral glucose or mixed meal tests in obese men.

PubMed

Matikainen, N; Söderlund, S; Björnson, E; Bogl, L H; Pietiläinen, K H; Hakkarainen, A; Lundbom, N; Eliasson, B; Räsänen, S M; Rivellese, A; Patti, L; Prinster, A; Riccardi, G; Després, J-P; Alméras, N; Holst, J J; Deacon, C F; Borén, J; Taskinen, M-R

2017-06-01

Incretin hormones glucagon-like peptide (GLP)-1 and glucose-dependent insulinotropic polypeptide (GIP) are affected early on in the pathogenesis of metabolic syndrome and type 2 diabetes. Epidemiologic studies consistently link high fructose consumption to insulin resistance but whether fructose consumption impairs the incretin response remains unknown. As many as 66 obese (BMI 26-40 kg/m 2 ) male subjects consumed fructose-sweetened beverages containing 75 g fructose/day for 12 weeks while continuing their usual lifestyle. Glucose, insulin, GLP-1 and GIP were measured during oral glucose tolerance test (OGTT) and triglycerides (TG), GLP-1, GIP and PYY during a mixed meal test before and after fructose intervention. Fructose intervention did not worsen glucose and insulin responses during OGTT, and GLP-1 and GIP responses during OGTT and fat-rich meal were unchanged. Postprandial TG response increased significantly, p = 0.004, and we observed small but significant increases in weight and liver fat content, but not in visceral or subcutaneous fat depots. However, even the subgroups who gained weight or liver fat during fructose intervention did not worsen their glucose, insulin, GLP-1 or PYY responses. A minor increase in GIP response during OGTT occurred in subjects who gained liver fat (p = 0.049). In obese males with features of metabolic syndrome, 12 weeks fructose intervention 75 g/day did not change glucose, insulin, GLP-1 or GIP responses during OGTT or GLP-1, GIP or PYY responses during a mixed meal. Therefore, fructose intake, even accompanied with mild weight gain, increases in liver fat and worsening of postprandial TG profile, does not impair glucose tolerance or gut incretin response to oral glucose or mixed meal challenge. Copyright © 2017 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.

Two-year efficacy and safety of AIR inhaled insulin in patients with type 1 diabetes: An open-label randomized controlled trial.

PubMed

Garg, Satish K; Mathieu, Chantal; Rais, Nadeem; Gao, Haitao; Tobian, Janet A; Gates, Jeffrey R; Ferguson, Jeffrey A; Webb, David M; Berclaz, Pierre-Yves

2009-09-01

Patients with type 1 diabetes require intensive insulin therapy for optimal glycemic control. AIR((R)) inhaled insulin (system from Eli Lilly and Company, Indianapolis, IN) (AIR is a registered trademark of Alkermes, Inc., Cambridge, MA) may be an efficacious and safe alternative to subcutaneously injected (SC) mealtime insulin. This was a Phase 3, 2-year, randomized, open-label, active-comparator, parallel-group study in 385 patients with type 1 diabetes who were randomly assigned to receive AIR insulin or SC insulin (regular human insulin or insulin lispro) at mealtimes. Both groups received insulin glargine once daily. Efficacy measures included mean change in hemoglobin A1C (A1C) from baseline to end point, eight-point self-monitored blood glucose profiles, and insulin dosage. Safety assessments included hypoglycemic events, pulmonary function tests, adverse events, and insulin antibody levels. In both treatment groups, only 20% of subjects reached the target of A1C <7.0%. A significant A1C difference of 0.44% was seen favoring SC insulin, with no difference between the groups in insulin doses or hypoglycemic events at end point. Patients in both treatment groups experienced progressive decreases in lung function, but larger (reversible) decrements in diffusing capacity of the lung for carbon monoxide (DL(CO)) were associated with AIR insulin treatment. Greater weight gain was seen with SC insulin treatment. The AIR inhaled insulin program was terminated by the sponsor prior to availability of any Phase 3 data for reasons unrelated to safety or efficacy. Despite early termination, this trial provides evidence that AIR insulin was less efficacious in lowering A1C and was associated with a greater decrease in DL(CO) and increased incidence of cough than SC insulin in patients with type 1 diabetes.

Insulin immuno-neutralization in fed chickens: effects on liver and muscle transcriptome.

PubMed

Simon, Jean; Milenkovic, Dragan; Godet, Estelle; Cabau, Cedric; Collin, Anne; Métayer-Coustard, Sonia; Rideau, Nicole; Tesseraud, Sophie; Derouet, Michel; Crochet, Sabine; Cailleau-Audouin, Estelle; Hennequet-Antier, Christelle; Gespach, Christian; Porter, Tom E; Duclos, Michel J; Dupont, Joëlle; Cogburn, Larry A

2012-03-01

Chickens mimic an insulin-resistance state by exhibiting several peculiarities with regard to plasma glucose level and its control by insulin. To gain insight into the role of insulin in the control of chicken transcriptome, liver and leg muscle transcriptomes were compared in fed controls and "diabetic" chickens, at 5 h after insulin immuno-neutralization, using 20.7K-chicken oligo-microarrays. At a level of false discovery rate <0.01, 1,573 and 1,225 signals were significantly modified by insulin privation in liver and muscle, respectively. Microarray data agreed reasonably well with qRT-PCR and some protein level measurements. Differentially expressed mRNAs with human ID were classified using Biorag analysis and Ingenuity Pathway Analysis. Multiple metabolic pathways, structural proteins, transporters and proteins of intracellular trafficking, major signaling pathways, and elements of the transcriptional control machinery were largely represented in both tissues. At least 42 mRNAs have already been associated with diabetes, insulin resistance, obesity, energy expenditure, or identified as sensors of metabolism in mice or humans. The contribution of the pathways presently identified to chicken physiology (particularly those not yet related to insulin) needs to be evaluated in future studies. Other challenges include the characterization of "unknown" mRNAs and the identification of the steps or networks, which disturbed tissue transcriptome so extensively, quickly after the turning off of the insulin signal. In conclusion, pleiotropic effects of insulin in chickens are further evidenced; major pathways controlled by insulin in mammals have been conserved despite the presence of unique features of insulin signaling in chicken muscle.

Mechanisms of β-cell functional adaptation to changes in workload

PubMed Central

Wortham, Matthew; Sander, Maike

2016-01-01

Insulin secretion must be tightly coupled to nutritional state to maintain blood glucose homeostasis. To this end, pancreatic β-cells sense and respond to changes in metabolic conditions, thereby anticipating insulin demands for a given physiological context. This is achieved in part through adjustments of nutrient metabolism, which is controlled at several levels including allosteric regulation, posttranslational modifications, and altered expression of metabolic enzymes. In this review, we discuss mechanisms of β-cell metabolic and functional adaptation in the context of two physiological states that alter glucose-stimulated insulin secretion: fasting and insulin resistance. We review current knowledge of metabolic changes that occur in the β-cell during adaptation and specifically discuss transcriptional mechanisms that underlie β-cell adaptation. A more comprehensive understanding of how β-cells adapt to changes in nutrient state could identify mechanisms to be co-opted for therapeutically modulating insulin secretion in metabolic disease. PMID:27615135

Chemically controlled closed-loop insulin delivery.

PubMed

Ravaine, Valérie; Ancla, Christophe; Catargi, Bogdan

2008-11-24

Alternative treatments for diabetes are currently being investigated to improve both patient comfort and avoid complications due to hyperglycaemia episodes. In the absence of a cure like pancreas or beta-islets transplants, the ideal method would be an artificial "closed-loop" system able to mimic pancreas activity. This would operate continuously and automatically, causing appropriate response to losses and gains in glucose levels. Chemically controlled closed-loop insulin delivery has been explored by two main strategies. The first one consists in delivering insulin with a glucose-responsive matrix. Polymeric hydrogels that swell or shrink according to the glucose concentration allow delivering insulin doses adapted to the glucose concentration. The second strategy consists in modifying insulin itself with glucose-sensitive functional groups that trigger its activity. Recent developments made in these areas represent significant progress in terms of biocompatibility, selectivity, pharmacokinetics, and easiness of administration, as required for in vivo applications. Although some issues still have to be overcome, this field of research is promising as a possible alternative to other approaches for diabetes treatment.

Association between insulin resistance and preeclampsia in obese non-diabetic women receiving metformin.

PubMed

Balani, Jyoti; Hyer, Steve; Syngelaki, Argyro; Akolekar, Ranjit; Nicolaides, Kypros H; Johnson, Antoinette; Shehata, Hassan

2017-12-01

To examine whether the reduced incidence of preeclampsia in non-diabetic obese pregnant women treated with metformin is mediated by changes in insulin resistance. This was a secondary analysis of obese pregnant women in a randomised trial (MOP trial). Fasting plasma glucose and insulin were measured in 384 of the 400 women who participated in the MOP trial. Homeostasis model assessment of insulin resistance (HOMA-IR) was compared in the metformin and placebo groups and in those that developed preeclampsia versus those that did not develop preeclampsia. At 28 weeks, median HOMA-IR was significantly lower in the metformin group. Logistic regression analysis demonstrated that there was a significant contribution in the prediction of preeclampsia from maternal history of chronic hypertension and gestational weight gain, but not HOMA-IR either at randomisation ( p  = 0.514) or at 28 weeks ( p  = 0.643). Reduced incidence of preeclampsia in non-diabetic obese pregnant women treated with metformin is unlikely to be due to changes in insulin resistance.

Meta-Analysis of Maternal and Neonatal Outcomes Associated with the Use of Insulin Glargine versus NPH Insulin during Pregnancy

PubMed Central

Lepercq, Jacques; Lin, Jay; Hall, Gillian C.; Wang, Edward; Dain, Marie-Paule; Riddle, Matthew C.; Home, Philip D.

2012-01-01

As glargine, an analog of human insulin, is increasingly used during pregnancy, a meta-analysis assessed its safety in this population. A systematic literature search identified studies of gestational or pregestational diabetes comparing use of insulin glargine with human NPH insulin, with at least 15 women in both arms. Data was extracted for maternal outcomes (weight at delivery, weight gain, 1st/3rd trimester HbA1c, severe hypoglycemia, gestation/new-onset hypertension, preeclampsia, and cesarean section) and neonatal outcomes (congenital malformations, gestational age at delivery, birth weight, macrosomia, LGA, 5 minute Apgar score >7, NICU admissions, respiratory distress syndrome, neonatal hypoglycemia, and hyperbilirubinemia). Relative risk ratios and weighted mean differences were determined using a random effect model. Eight studies of women using glargine (331) or NPH (371) were analyzed. No significant differences in the efficacy and safety-related outcomes were found between glargine and NPH use during pregnancy. PMID:22685467

E-cadherin and cell adhesion: a role in architecture and function in the pancreatic islet.

PubMed

Rogers, Gareth J; Hodgkin, Matthew N; Squires, Paul E

2007-01-01

The efficient secretion of insulin from beta-cells requires extensive intra-islet communication. The cell surface adhesion protein epithelial (E)-cadherin (ECAD) establishes and maintains epithelial tissues such as the islets of Langerhans. In this study, the role of ECAD in regulating insulin secretion from pseudoislets was investigated. The effect of an immuno-neutralising ECAD on gross morphology, cytosolic calcium signalling, direct cell-to-cell communication and insulin secretion was assessed by fura-2 microfluorimetry, Lucifer Yellow dye injection and insulin ELISA in an insulin-secreting model system. Antibody blockade of ECAD reduces glucose-evoked changes in [Ca(2+)](i) and insulin secretion. Neutralisation of ECAD causes a breakdown in the glucose-stimulated synchronicity of calcium oscillations between discrete regions within the pseudoislet, and the transfer of dye from an individual cell within a cell cluster is attenuated in the absence of ECAD ligation, demonstrating that gap junction communication is disrupted. The functional consequence of neutralising ECAD is a significant reduction in insulin secretion. Cell adhesion via ECAD has distinct roles in the regulation of intercellular communication between beta-cells within islets, with potential repercussions for insulin secretion.

Three-dimensional printed polymeric system to encapsulate human mesenchymal stem cells differentiated into islet-like insulin-producing aggregates for diabetes treatment.

PubMed

Sabek, Omaima M; Farina, Marco; Fraga, Daniel W; Afshar, Solmaz; Ballerini, Andrea; Filgueira, Carly S; Thekkedath, Usha R; Grattoni, Alessandro; Gaber, A Osama

2016-01-01

Diabetes is one of the most prevalent, costly, and debilitating diseases in the world. Pancreas and islet transplants have shown success in re-establishing glucose control and reversing diabetic complications. However, both are limited by donor availability, need for continuous immunosuppression, loss of transplanted tissue due to dispersion, and lack of vascularization. To overcome the limitations of poor islet availability, here, we investigate the potential of bone marrow-derived mesenchymal stem cells differentiated into islet-like insulin-producing aggregates. Islet-like insulin-producing aggregates, characterized by gene expression, are shown to be similar to pancreatic islets and display positive immunostaining for insulin and glucagon. To address the limits of current encapsulation systems, we developed a novel three-dimensional printed, scalable, and potentially refillable polymeric construct (nanogland) to support islet-like insulin-producing aggregates' survival and function in the host body. In vitro studies showed that encapsulated islet-like insulin-producing aggregates maintained viability and function, producing steady levels of insulin for at least 4 weeks. Nanogland-islet-like insulin-producing aggregate technology here investigated as a proof of concept holds potential as an effective and innovative approach for diabetes cell therapy.

Three-dimensional printed polymeric system to encapsulate human mesenchymal stem cells differentiated into islet-like insulin-producing aggregates for diabetes treatment

PubMed Central

Sabek, Omaima M; Farina, Marco; Fraga, Daniel W; Afshar, Solmaz; Ballerini, Andrea; Filgueira, Carly S; Thekkedath, Usha R; Grattoni, Alessandro; Gaber, A Osama

2016-01-01

Diabetes is one of the most prevalent, costly, and debilitating diseases in the world. Pancreas and islet transplants have shown success in re-establishing glucose control and reversing diabetic complications. However, both are limited by donor availability, need for continuous immunosuppression, loss of transplanted tissue due to dispersion, and lack of vascularization. To overcome the limitations of poor islet availability, here, we investigate the potential of bone marrow–derived mesenchymal stem cells differentiated into islet-like insulin-producing aggregates. Islet-like insulin-producing aggregates, characterized by gene expression, are shown to be similar to pancreatic islets and display positive immunostaining for insulin and glucagon. To address the limits of current encapsulation systems, we developed a novel three-dimensional printed, scalable, and potentially refillable polymeric construct (nanogland) to support islet-like insulin-producing aggregates’ survival and function in the host body. In vitro studies showed that encapsulated islet-like insulin-producing aggregates maintained viability and function, producing steady levels of insulin for at least 4 weeks. Nanogland—islet-like insulin-producing aggregate technology here investigated as a proof of concept holds potential as an effective and innovative approach for diabetes cell therapy. PMID:27152147

Insulin Therapy in People With Type 2 Diabetes: Opportunities and Challenges?

PubMed Central

Home, Philip; Riddle, Matthew; Cefalu, William T.; Bailey, Clifford J.; Bretzel, Reinhard G.; del Prato, Stefano; Leroith, Derek; Schernthaner, Guntram; van Gaal, Luc; Raz, Itamar

2014-01-01

Given the continued interest in defining the optimal management of individuals with type 2 diabetes, the Editor of Diabetes Care convened a working party of diabetes specialists to examine this topic in the context of insulin therapy. This was prompted by recent new evidence on the use of insulin in such people. The group was aware of evidence that the benefits of insulin therapy are still usually offered late, and thus the aim of the discussion was how to define the optimal timing and basis for decisions regarding insulin and to apply these concepts in practice. It was noted that recent evidence had built upon that of the previous decades, together confirming the benefits and safety of insulin therapy, albeit with concerns about the potential for hypoglycemia and gain in body weight. Insulin offers a unique ability to control hyperglycemia, being used from the time of diagnosis in some circumstances, when metabolic control is disturbed by medical illness, procedures, or therapy, as well as in the longer term in ambulatory care. For those previously starting insulin, various other forms of therapy can be added later, which offer complementary effects appropriate to individual needs. Here we review current evidence and circumstances in which insulin can be used, consider individualized choices of alternatives and combination regimens, and offer some guidance on personalized targets and tactics for glycemic control in type 2 diabetes. PMID:24855154

Increase in Pancreatic Proinsulin and Preservation of β-Cell Mass in Autoantibody-Positive Donors Prior to Type 1 Diabetes Onset

PubMed Central

Rodriguez-Calvo, Teresa; Zapardiel-Gonzalo, Jose; Amirian, Natalie; Castillo, Ericka; Lajevardi, Yasaman; Krogvold, Lars; Dahl-Jørgensen, Knut

2017-01-01

Type 1 diabetes is characterized by the loss of insulin production caused by β-cell dysfunction and/or destruction. The hypothesis that β-cell loss occurs early during the prediabetic phase has recently been challenged. Here we show, for the first time in situ, that in pancreas sections from autoantibody-positive (Ab+) donors, insulin area and β-cell mass are maintained before disease onset and that production of proinsulin increases. This suggests that β-cell destruction occurs more precipitously than previously assumed. Indeed, the pancreatic proinsulin-to-insulin area ratio was also increased in these donors with prediabetes. Using high-resolution confocal microscopy, we found a high accumulation of vesicles containing proinsulin in β-cells from Ab+ donors, suggesting a defect in proinsulin conversion or an accumulation of immature vesicles caused by an increase in insulin demand and/or a dysfunction in vesicular trafficking. In addition, islets from Ab+ donors were larger and contained a higher number of β-cells per islet. Our data indicate that β-cell mass (and function) is maintained until shortly before diagnosis and declines rapidly at the time of clinical onset of disease. This suggests that secondary prevention before onset, when β-cell mass is still intact, could be a successful therapeutic strategy. PMID:28137793

The diet-derived short chain fatty acid propionate improves beta-cell function in humans and stimulates insulin secretion from human islets in vitro.

PubMed

Pingitore, Attilio; Chambers, Edward S; Hill, Thomas; Maldonado, Inmaculada Ruz; Liu, Bo; Bewick, Gavin; Morrison, Douglas J; Preston, Tom; Wallis, Gareth A; Tedford, Catriona; Castañera González, Ramón; Huang, Guo C; Choudhary, Pratik; Frost, Gary; Persaud, Shanta J

2017-02-01

Diet-derived short chain fatty acids (SCFAs) improve glucose homeostasis in vivo, but the role of individual SCFAs and their mechanisms of action have not been defined. This study evaluated the effects of increasing colonic delivery of the SCFA propionate on β-cell function in humans and the direct effects of propionate on isolated human islets in vitro. For 24 weeks human subjects ingested an inulin-propionate ester that delivers propionate to the colon. Acute insulin, GLP-1 and non-esterified fatty acid (NEFA) levels were quantified pre- and post-supplementation in response to a mixed meal test. Expression of the SCFA receptor FFAR2 in human islets was determined by western blotting and immunohistochemistry. Dynamic insulin secretion from perifused human islets was quantified by radioimmunoassay and islet apoptosis was determined by quantification of caspase 3/7 activities. Colonic propionate delivery in vivo was associated with improved β-cell function with increased insulin secretion that was independent of changes in GLP-1 levels. Human islet β-cells expressed FFAR2 and propionate potentiated dynamic glucose-stimulated insulin secretion in vitro, an effect that was dependent on signalling via protein kinase C. Propionate also protected human islets from apoptosis induced by the NEFA sodium palmitate and inflammatory cytokines. Our results indicate that propionate has beneficial effects on β-cell function in vivo, and in vitro analyses demonstrated that it has direct effects to potentiate glucose-stimulated insulin release and maintain β-cell mass through inhibition of apoptosis. These observations support ingestion of propiogenic dietary fibres to maintain healthy glucose homeostasis. © 2016 John Wiley & Sons Ltd.

KATP Channel Mutations and Neonatal Diabetes.

PubMed

Shimomura, Kenju; Maejima, Yuko

2017-09-15

Since the discovery of the K ATP channel in 1983, numerous studies have revealed its physiological functions. The K ATP channel is expressed in various organs, including the pancreas, brain and skeletal muscles. It functions as a "metabolic sensor" that converts the metabolic status to electrical activity. In pancreatic beta-cells, the K ATP channel regulates the secretion of insulin by sensing a change in the blood glucose level and thus maintains glucose homeostasis. In 2004, heterozygous gain-of-function mutations in the KCNJ11 gene, which encodes the Kir6.2 subunit of the K ATP channel, were found to cause neonatal diabetes. In some mutations, diabetes is accompanied by severe neurological symptoms [developmental delay, epilepsy, neonatal diabetes (DEND) syndrome]. This review focuses on mutations of Kir6.2, the pore-forming subunit and sulfonylurea receptor (SUR) 1, the regulatory subunit of the K ATP channel, which cause neonatal diabetes/DEND syndrome and also discusses the findings of the pathological mechanisms that are associated with neonatal diabetes, and its neurological features.

Performance Analysis of Fuzzy-PID Controller for Blood Glucose Regulation in Type-1 Diabetic Patients.

PubMed

Yadav, Jyoti; Rani, Asha; Singh, Vijander

2016-12-01

This paper presents Fuzzy-PID (FPID) control scheme for a blood glucose control of type 1 diabetic subjects. A new metaheuristic Cuckoo Search Algorithm (CSA) is utilized to optimize the gains of FPID controller. CSA provides fast convergence and is capable of handling global optimization of continuous nonlinear systems. The proposed controller is an amalgamation of fuzzy logic and optimization which may provide an efficient solution for complex problems like blood glucose control. The task is to maintain normal glucose levels in the shortest possible time with minimum insulin dose. The glucose control is achieved by tuning the PID (Proportional Integral Derivative) and FPID controller with the help of Genetic Algorithm and CSA for comparative analysis. The designed controllers are tested on Bergman minimal model to control the blood glucose level in the facets of parameter uncertainties, meal disturbances and sensor noise. The results reveal that the performance of CSA-FPID controller is superior as compared to other designed controllers.

Insulin and GLP-1 infusions demonstrate the onset of adipose-specific insulin resistance in a large fasting mammal: potential glucogenic role for GLP-1.

PubMed

Viscarra, Jose A; Rodriguez, Ruben; Vazquez-Medina, Jose Pablo; Lee, Andrew; Tift, Michael S; Tavoni, Stephen K; Crocker, Daniel E; Ortiz, Rudy M

2013-08-01

Prolonged food deprivation increases lipid oxidation and utilization, which may contribute to the onset of the insulin resistance associated with fasting. Because insulin resistance promotes the preservation of glucose and oxidation of fat, it has been suggested to be an adaptive response to food deprivation. However, fasting mammals exhibit hypoinsulinemia, suggesting that the insulin resistance-like conditions they experience may actually result from reduced pancreatic sensitivity to glucose/capacity to secrete insulin. To determine whether fasting results in insulin resistance or in pancreatic dysfunction, we infused early- and late-fasted seals (naturally adapted to prolonged fasting) with insulin (0.065 U/kg), and a separate group of late-fasted seals with low (10 pM/kg) or high (100 pM/kg) dosages of glucagon-like peptide-1 (GLP-1) immediately following a glucose bolus (0.5g/kg), and measured the systemic and cellular responses. Because GLP-1 facilitates glucose-stimulated insulin secretion, these infusions provide a method to assess pancreatic insulin-secreting capacity. Insulin infusions increased the phosphorylation of insulin receptor and Akt in adipose and muscle of early and late fasted seals; however the timing of the signaling response was blunted in adipose of late fasted seals. Despite the dose-dependent increases in insulin and increased glucose clearance (high dose), both GLP-1 dosages produced increases in plasma cortisol and glucagon, which may have contributed to the glucogenic role of GLP-1. Results suggest that fasting induces adipose-specific insulin resistance in elephant seal pups, while maintaining skeletal muscle insulin sensitivity, and therefore suggests that the onset of insulin resistance in fasting mammals is an evolved response to cope with prolonged food deprivation.

The effects of exenatide twice daily compared to insulin lispro added to basal insulin in Latin American patients with type 2 diabetes: A retrospective analysis of the 4B trial.

PubMed

de Lapertosa, Silvia Beatriz Gorban; Frechtel, Gustavo; Hardy, Elise; Sauque-Reyna, Leobardo

2016-12-01

Socioeconomic changes in Latin American countries have led to an increased prevalence of type 2 diabetes (T2D). We examined the effects of exenatide twice daily (BID) or insulin lispro, each added to insulin glargine, in Latin American patients with T2D. This was a subgroup analysis of patients from Argentina and Mexico in the 4B study (N=114). Patients with glycated hemoglobin (HbA1c) of 7.0-10.0% (53-86mmol/mol) after 12weeks of intensive basal insulin optimization were randomized to exenatide BID or thrice-daily insulin lispro added to insulin glargine and metformin. After 30weeks, addition of exenatide BID or insulin lispro resulted in significant (P<0.0001) reductions in HbA1c (exenatide BID: -0.9% [-10mmol/mol]; insulin lispro: -1.2% [-13mmol/mol]). Weight was stable in the exenatide BID group (-0.1kg) and increased significantly (+3.4kg; P<0.0001) with insulin lispro. Major and minor hypoglycemia occurred less frequently (40 vs. 253 events) with exenatide BID compared with insulin lispro. Gastrointestinal adverse events of nausea, diarrhea, and vomiting occurred more frequently with exenatide BID than with insulin lispro. Both exenatide BID and prandial insulin lispro, each added to basal insulin glargine, were effective at reducing HbA1c in Latin American patients. Treatment with exenatide BID resulted in stable weight but more gastrointestinal adverse events. Treatment with insulin lispro resulted in weight gain and an increased risk of hypoglycemia. These findings support the addition of exenatide BID to insulin glargine as an option for Latin American patients unable to achieve glycemic control on basal insulin alone. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Gestational Protein Restriction Impairs Insulin-Regulated Glucose Transport Mechanisms in Gastrocnemius Muscles of Adult Male Offspring

PubMed Central

Blesson, Chellakkan S.; Sathishkumar, Kunju; Chinnathambi, Vijayakumar

2014-01-01

Type II diabetes originates from various genetic and environmental factors. Recent studies showed that an adverse uterine environment such as that caused by a gestational low-protein (LP) diet can cause insulin resistance in adult offspring. The mechanism of insulin resistance induced by gestational protein restriction is not clearly understood. Our aim was to investigate the role of insulin signaling molecules in gastrocnemius muscles of gestational LP diet–exposed male offspring to understand their role in LP-induced insulin resistance. Pregnant Wistar rats were fed a control (20% protein) or isocaloric LP (6%) diet from gestational day 4 until delivery and a normal diet after weaning. Only male offspring were used in this study. Glucose and insulin responses were assessed after a glucose tolerance test. mRNA and protein levels of molecules involved in insulin signaling were assessed at 4 months in gastrocnemius muscles. Muscles were incubated ex vivo with insulin to evaluate insulin-induced phosphorylation of insulin receptor (IR), Insulin receptor substrate-1, Akt, and AS160. LP diet-fed rats gained less weight than controls during pregnancy. Male pups from LP diet–fed mothers were smaller but exhibited catch-up growth. Plasma glucose and insulin levels were elevated in LP offspring when subjected to a glucose tolerance test; however, fasting levels were comparable. LP offspring showed increased expression of IR and AS160 in gastrocnemius muscles. Ex vivo treatment of muscles with insulin showed increased phosphorylation of IR (Tyr972) in controls, but LP rats showed higher basal phosphorylation. Phosphorylation of Insulin receptor substrate-1 (Tyr608, Tyr895, Ser307, and Ser318) and AS160 (Thr642) were defective in LP offspring. Further, glucose transporter type 4 translocation in LP offspring was also impaired. A gestational LP diet leads to insulin resistance in adult offspring by a mechanism involving inefficient insulin-induced IR, Insulin receptor substrate-1, and AS160 phosphorylation and impaired glucose transporter type 4 translocation. PMID:24797633

Modelling the regulatory system for diabetes mellitus with a threshold window

NASA Astrophysics Data System (ADS)

Yang, Jin; Tang, Sanyi; Cheke, Robert A.

2015-05-01

Piecewise (or non-smooth) glucose-insulin models with threshold windows for type 1 and type 2 diabetes mellitus are proposed and analyzed with a view to improving understanding of the glucose-insulin regulatory system. For glucose-insulin models with a single threshold, the existence and stability of regular, virtual, pseudo-equilibria and tangent points are addressed. Then the relations between regular equilibria and a pseudo-equilibrium are studied. Furthermore, the sufficient and necessary conditions for the global stability of regular equilibria and the pseudo-equilibrium are provided by using qualitative analysis techniques of non-smooth Filippov dynamic systems. Sliding bifurcations related to boundary node bifurcations were investigated with theoretical and numerical techniques, and insulin clinical therapies are discussed. For glucose-insulin models with a threshold window, the effects of glucose thresholds or the widths of threshold windows on the durations of insulin therapy and glucose infusion were addressed. The duration of the effects of an insulin injection is sensitive to the variation of thresholds. Our results indicate that blood glucose level can be maintained within a normal range using piecewise glucose-insulin models with a single threshold or a threshold window. Moreover, our findings suggest that it is critical to individualise insulin therapy for each patient separately, based on initial blood glucose levels.

A Review of the Security of Insulin Pump Infusion Systems

PubMed Central

Paul, Nathanael; Kohno, Tadayoshi; Klonoff, David C

2011-01-01

Insulin therapy has enabled patients with diabetes to maintain blood glucose control to lead healthier lives. Today, rather than injecting insulin manually using syringes, a patient can use a device such as an insulin pump to deliver insulin programmatically. This allows for more granular insulin delivery while attaining blood glucose control. Insulin pump system features have increasingly benefited patients, but the complexity of the resulting system has grown in parallel. As a result, security breaches that can negatively affect patient health are now possible. Rather than focus on the security of a single device, we concentrate on protecting the security of the entire system. In this article, we describe the security issues as they pertain to an insulin pump system that includes an embedded system of components, which include the insulin pump, continuous glucose management system, blood glucose monitor, and other associated devices (e.g., a mobile phone or personal computer). We detail not only the growing wireless communication threat in each system component, but also describe additional threats to the system (e.g., availability and integrity). Our goal is to help create a trustworthy infusion pump system that will ultimately strengthen pump safety, and we describe mitigating solutions to address identified security issues. PMID:22226278

A review of the security of insulin pump infusion systems.

PubMed

Paul, Nathanael; Kohno, Tadayoshi; Klonoff, David C

2011-11-01

Insulin therapy has enabled patients with diabetes to maintain blood glucose control to lead healthier lives. Today, rather than injecting insulin manually using syringes, a patient can use a device such as an insulin pump to deliver insulin programmatically. This allows for more granular insulin delivery while attaining blood glucose control. Insulin pump system features have increasingly benefited patients, but the complexity of the resulting system has grown in parallel. As a result, security breaches that can negatively affect patient health are now possible. Rather than focus on the security of a single device, we concentrate on protecting the security of the entire system. In this article, we describe the security issues as they pertain to an insulin pump system that includes an embedded system of components, which include the insulin pump, continuous glucose management system, blood glucose monitor, and other associated devices (e.g., a mobile phone or personal computer). We detail not only the growing wireless communication threat in each system component, but also describe additional threats to the system (e.g., availability and integrity). Our goal is to help create a trustworthy infusion pump system that will ultimately strengthen pump safety, and we describe mitigating solutions to address identified security issues. © 2011 Diabetes Technology Society.

Dynamics in insulin requirements and treatment safety.

PubMed

Harper, R; Donnelly, R; Bi, Yixi; Bashan, E; Minhas, R; Hodish, I

2016-01-01

The majority of insulin users have elevated HbA1c. There is growing recognition that the low success rates are due to variations in insulin requirements. Thus, frequent dosage adjustments are needed. In practice, adjustments occur sporadically due to limited provider availability. We investigated intra-individual dynamics of insulin requirements using data from a service evaluation of the d-Nav® Insulin Guidance Service. This service facilitates automated insulin dosage adjustments, as often as needed, to achieve and maintain optimal glycemic balance. Data were collected from subjects who have been using the service for more than a year. Events of considerable and persistent decrease in insulin requirements were identified by drops in total daily insulin ≥25%. Overall, 62 patients were studied over an average period of 2.1±0.5 (mean±standard deviation) years. Stability in HbA1c was attained after ~3 quarters at 7.4%±0.2% (57.4mmol/mol±1mmol/mol). Events were identified in 56.5% of the patients. On average, each affected patient had 0.8±0.4 events per year, lasting 9.7±6.6weeks, while total daily insulin dosage decreased by 41.4±13.4%. Our findings may call attention to a major contributing factor to hypoglycemia among insulin users. In reality, insulin dosage is seldom adjusted and thus transient periods of decrease in insulin requirements and overtreatment are usually overlooked. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Insulin resistance in striated muscle-specific integrin receptor beta1-deficient mice.

PubMed

Zong, Haihong; Bastie, Claire C; Xu, Jun; Fassler, Reinhard; Campbell, Kevin P; Kurland, Irwin J; Pessin, Jeffrey E

2009-02-13

Integrin receptor plays key roles in mediating both inside-out and outside-in signaling between cells and the extracellular matrix. We have observed that the tissue-specific loss of the integrin beta1 subunit in striated muscle results in a near complete loss of integrin beta1 subunit protein expression concomitant with a loss of talin and to a lesser extent, a reduction in F-actin content. Muscle-specific integrin beta1-deficient mice had no significant difference in food intake, weight gain, fasting glucose, and insulin levels with their littermate controls. However, dynamic analysis of glucose homeostasis using euglycemichyperinsulinemic clamps demonstrated a 44 and 48% reduction of insulin-stimulated glucose infusion rate and glucose clearance, respectively. The whole body insulin resistance resulted from a specific inhibition of skeletal muscle glucose uptake and glycogen synthesis without any significant effect on the insulin suppression of hepatic glucose output or insulin-stimulated glucose uptake in adipose tissue. The reduction in skeletal muscle insulin responsiveness occurred without any change in GLUT4 protein expression levels but was associated with an impairment of the insulin-stimulated protein kinase B/Akt serine 473 phosphorylation but not threonine 308. The inhibition of insulin-stimulated serine 473 phosphorylation occurred concomitantly with a decrease in integrin-linked kinase expression but with no change in the mTOR.Rictor.LST8 complex (mTORC2). These data demonstrate an in vivo crucial role of integrin beta1 signaling events in mediating cross-talk to that of insulin action.

Insulin secretion and insulin resistance in Korean women with gestational diabetes mellitus and impaired glucose tolerance

PubMed Central

Yang, Sae Jeong; Kim, Tae Nyun; Baik, Sei Hyun; Kim, Tae Sun; Lee, Kwan Woo; Nam, Moonsuk; Park, Yong Soo; Woo, Jeong-Teak; Kim, Young Seol

2013-01-01

Background/Aims The aim was to compare the insulin sensitivity and secretion index of pregnant Korean women with normal glucose tolerance (NGT), gestational impaired glucose tolerance (GIGT; only one abnormal value according to the Carpenter and Coustan criteria), and gestational diabetes mellitus (GDM). Methods A cross-sectional study was performed with 1,163 pregnant women with positive (1-hour plasma glucose ≥ 7.2 mmol/L) in a 50-g oral glucose challenge test (OGCT). The 100-g oral glucose tolerance test (OGTT) was used to stratify the participants into three groups: NGT (n = 588), GIGT (n = 294), and GDM (n = 281). Results The GDM group had higher homeostasis model assessment of insulin resistance and lower insulin sensitivity index (ISOGTT), quantitative insulin sensitivity check index, homeostasis model assessment for estimation of index β-cell secretion (HOMA-B), first and second phase insulin secretion, and insulin secretion-sensitivity index (ISSI) than the NGT group (p ≤ 0.001 for all). Moreover, the GIGT group had lower ISOGTT, HOMA-B, first and second phase insulin secretion, and ISSI than the NGT group (p < 0.001 for all). Among the GIGT subjects, the 1-hour plasma glucose abnormal levels group showed significantly greater weight gain during pregnancy and higher values in the 50-g OGCT than the other two groups. Moreover, the 1-hour and 2-hour abnormal levels groups had poorer insulin secretion status than the 3-hour abnormal levels group. Conclusions Korean women with GDM show impairments of both insulin secretion and insulin sensitivity. In addition, GIGT is associated with both β-cell dysfunction and insulin resistance. PMID:23682224

The Effects of Insulin Resistance on Individual Tissues: An Application of a Mathematical Model of Metabolism in Humans.

PubMed

Pearson, Taliesin; Wattis, Jonathan A D; King, John R; MacDonald, Ian A; Mazzatti, Dawn J

2016-06-01

Whilst the human body expends energy constantly, the human diet consists of a mix of carbohydrates and fats delivered in a discontinuous manner. To deal with this sporadic supply of energy, there are transport, storage and utilisation mechanisms, for both carbohydrates and fats, around all tissues of the body. Insulin-resistant states such as type 2 diabetes and obesity are characterised by reduced efficiency of these mechanisms. Exactly how these insulin-resistant states develop, for example whether there is an order in which tissues become insulin resistant, is an active area of research with the hope of gaining a better overall understanding of insulin resistance. In this paper, we use a previously derived system of 12 first-order coupled differential equations that describe the transport between, and storage in, different tissues of the human body. We briefly revisit the derivation of the model before parametrising the model to account for insulin resistance. We then solve the model numerically, separately simulating each individual tissue as insulin resistant, and discuss and compare these results, drawing three main conclusions. The implications of these results are in accordance with biological intuition. First, insulin resistance in a tissue creates a knock-on effect on the other tissues in the body, whereby they attempt to compensate for the reduced efficiency of the insulin-resistant tissue. Second, insulin resistance causes a fatty liver, and the insulin resistance of tissues other than the liver can cause fat to accumulate in the liver. Finally, although insulin resistance in individual tissues can cause slightly reduced skeletal muscle metabolic flexibility, it is when the whole body is insulin resistant that the biggest effect on skeletal muscle flexibility is seen.

Postprandial blood glucose control in type 1 diabetes for carbohydrates with varying glycemic index foods.

PubMed

Hashimoto, Shogo; Noguchi, Claudia Cecilia Yamamoto; Furutani, Eiko

2014-01-01

Treatment of type 1 diabetes consists of maintaining postprandial normoglycemia using the correct prandial insulin dose according to food intake. Nonetheless, it is hardly achieved in practice, which results in several diabetes-related complications. In this study we present a feedforward plus feedback blood glucose control system that considers the glycemic index of foods. It consists of a preprandial insulin bolus whose optimal bolus dose and timing are stated as a minimization problem, which is followed by a postprandial closed-loop control based on model predictive control. Simulation results show that, for a representative carbohydrate intake of 50 g, the present control system is able to maintain postprandial glycemia below 140 mg/dL while preventing postprandial hypoglycemia as well.

The effect of insulin upon the influx of tryptophan into the brain of the rabbit.

PubMed

Daniel, P M; Love, E R; Moorhouse, S R; Pratt, O E

1981-03-01

1. The effect of hyperinsulinaemia upon the influx of tryptophan into the brain was determined. A raised level of insulin was maintained in the circulation of rabbits for periods of up to 120 min by means of a continuous, programmed intravenous injection of the hormone, given by an electronically controlled variable-drive syringe. A similar, appropriately programmed, intravenous injection of glucose, given simultaneously with the insulin, maintained the concentration of the blood glucose within normal limits throughout each experiment, so that the results were not vitiated by the development of hypoglycaemia. 2. Raised levels of insulin in the blood affect the supply of tryptophan to the brain in two opposing ways: (a) by increasing the binding of tryptophan to the albumin in the blood, thereby reducing the level of the free tryptophan in the circulation by about a half, which would decrease the influx of tryptophan into the brain; (b) by simultaneously reducing the levels in the blood of six or more of the amino acids which compete with tryptophan for transport carriers into the brain, which would increase the influx of tryptophan. The net result of these two opposing effects is that insulin causes only a slight increase in the influx of tryptophan into the brain. 3. To account in quantitative terms for the effect of insulin upon the influx of tryptophan into the brain it proved necessary to make one assumption. This assumption was that a predictable proportion of the tryptophan which is loosely bound to blood albumin is being stripped off this protein by the transport carrier located on the luminal surface membranes of the endothelial cells during the passage of the blood through the cerebral capillaries. If this assumption is accepted the work reported here explains adequately the effect of insulin on the influx of tryptophan into the brain.

Metformin ameliorates high uric acid-induced insulin resistance in skeletal muscle cells.

PubMed

Yuan, Huier; Hu, Yaqiu; Zhu, Yuzhang; Zhang, Yongneng; Luo, Chaohuan; Li, Zhi; Wen, Tengfei; Zhuang, Wanling; Zou, Jinfang; Hong, Liangli; Zhang, Xin; Hisatome, Ichiro; Yamamoto, Tetsuya; Cheng, Jidong

2017-03-05

Hyperuricemia occurs together with abnormal glucose metabolism and insulin resistance. Skeletal muscle is an important organ of glucose uptake, disposal, and storage. Metformin activates adenosine monophosphate-activated protein kinase (AMPK) to regulate insulin signaling and promote the translocation of glucose transporter type 4 (GLUT4), thereby stimulating glucose uptake to maintain energy balance. Our previous study showed that high uric acid (HUA) induced insulin resistance in skeletal muscle tissue. However, the mechanism of metformin ameliorating UA-induced insulin resistance in muscle cells is unknown and we aimed to determine it. In this study, differentiated C2C12 cells were exposed to UA (15 mg/dl), then reactive oxygen species (ROS) was detected with DCFH-DA and glucose uptake with 2-NBDG. The levels of phospho-insulin receptor substrate 1 (IRS1; Ser307), phospho-AKT (Ser473) and membrane GLUT4 were examined by western blot analysis. The impact of metformin on UA-induced insulin resistance was monitored by adding Compound C, an AMPK inhibitor, and LY294002, a PI3K/AKT inhibitor. Our data indicate that UA can increase ROS production, inhibit IRS1-AKT signaling and insulin-stimulated glucose uptake, and induce insulin resistance in C2C12 cells. Metformin can reverse this process by increasing intracellular glucose uptake and ameliorating UA-induced insulin resistance. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Chronic hyperinsulinemia contributes to insulin resistance under dietary restriction in association with altered lipid metabolism in Zucker diabetic fatty rats.

PubMed

Morita, Ippei; Tanimoto, Keiichi; Akiyama, Nobuteru; Naya, Noriyuki; Fujieda, Kumiko; Iwasaki, Takanori; Yukioka, Hideo

2017-04-01

Hyperinsulinemia is widely thought to be a compensatory response to insulin resistance, whereas its potentially causal role in the progression of insulin resistance remains to be established. Here, we aimed to examine whether hyperinsulinemia could affect the progression of insulin resistance in Zucker fatty diabetic (ZDF) rats. Male ZDF rats at 8 wk of age were fed a diet ad libitum (AL) or dietary restriction (DR) of either 15 or 30% from AL feeding over 6 wk. Insulin sensitivity was determined by hyperinsulinemic euglycemic clamp. ZDF rats in the AL group progressively developed hyperglycemia and hyperinsulinemia by 10 wk of age, and then plasma insulin rapidly declined to nearly normal levels by 12 wk of age. Compared with AL group, DR groups showed delayed onset of hyperglycemia and persistent hyperinsulinemia, leading to weight gain and raised plasma triglycerides and free fatty acids by 14 wk of age. Notably, insulin sensitivity was significantly reduced in the DR group rather than the AL group and inversely correlated with plasma levels of insulin and triglyceride but not glucose. Moreover, enhanced lipid deposition and upregulation of genes involved in lipogenesis were detected in liver, skeletal muscle, and adipose tissues of the DR group rather than the AL group. Alternatively, continuous hyperinsulinemia induced by insulin pellet implantation produced a decrease in insulin sensitivity in ZDF rats. These results suggest that chronic hyperinsulinemia may lead to the progression of insulin resistance under DR conditions in association with altered lipid metabolism in peripheral tissues in ZDF rats. Copyright © 2017 the American Physiological Society.

E4orf1 induction in adipose tissue promotes insulin-independent signaling in the adipocyte

PubMed Central

Kusminski, Christine M.; Gallardo-Montejano, Violeta I.; Wang, Zhao V.; Hegde, Vijay; Bickel, Perry E.; Dhurandhar, Nikhil V.; Scherer, Philipp E.

2015-01-01

Background/Purpose Type 2 diabetes remains a worldwide epidemic with major pathophysiological changes as a result of chronic insulin resistance. Insulin regulates numerous biochemical pathways related to carbohydrate and lipid metabolism. Methods We have generated a novel mouse model that allows us to constitutively activate, in an inducible fashion, the distal branch of the insulin signaling transduction pathway specifically in adipocytes. Results Using the adenoviral 36 E4orf1 protein, we chronically stimulate locally the Ras-ERK-MAPK signaling pathway. At the whole body level, this leads to reduced body-weight gain under a high fat diet challenge. Despite overlapping glucose tolerance curves, there is a reduced requirement for insulin action under these conditions. The mice further exhibit reduced circulating adiponectin levels that ultimately lead to impaired lipid clearance, and inflamed and fibrotic white adipose tissues. Nevertheless, they are protected from diet-induced hepatic steatosis. As we observe constitutively elevated p-Akt levels in the adipocytes, even under conditions of low insulin levels, this pinpoints enhanced Ras-ERK-MAPK signaling in transgenic adipocytes as a potential alternative route to bypass proximal insulin signaling events. Conclusion We conclude that E4orf1 expression in the adipocyte leads to enhanced baseline activation of the distal insulin signaling node, yet impaired insulin receptor stimulation in the presence of insulin, with important implications for the regulation of adiponectin secretion. The resulting systemic phenotype is complex, yet highlights the powerful nature of manipulating selective branches of the insulin signaling network within the adipocyte. PMID:26500839

Comparison of the physiological relevance of systemic vs. portal insulin delivery to evaluate whole body glucose flux during an insulin clamp

PubMed Central

Farmer, Tiffany D.; Jenkins, Erin C.; O'Brien, Tracy P.; McCoy, Gregory A.; Havlik, Allison E.; Nass, Erik R.; Nicholson, Wendell E.; Printz, Richard L.

2014-01-01

To understand the underlying pathology of metabolic diseases, such as diabetes, an accurate determination of whole body glucose flux needs to be made by a method that maintains key physiological features. One such feature is a positive differential in insulin concentration between the portal venous and systemic arterial circulation (P/S-IG). P/S-IG during the determination of the relative contribution of liver and extra-liver tissues/organs to whole body glucose flux during an insulin clamp with either systemic (SID) or portal (PID) insulin delivery was examined with insulin infusion rates of 1, 2, and 5 mU·kg−1·min−1 under either euglycemic or hyperglycemic conditions in 6-h-fasted conscious normal rats. A P/S-IG was initially determined with endogenous insulin secretion to exist with a value of 2.07. During an insulin clamp, while inhibiting endogenous insulin secretion by somatostatin, P/S-IG remained at 2.2 with PID, whereas, P/S-IG disappeared completely with SID, which exhibited higher arterial and lower portal insulin levels compared with PID. Consequently, glucose disappearance rates and muscle glycogen synthetic rates were higher, but suppression of endogenous glucose production and liver glycogen synthetic rates were lower with SID compared with PID. When the insulin clamp was performed with SID at 2 and 5 mU·kg−1·min−1 without managing endogenous insulin secretion under euglycemic but not hyperglycemic conditions, endogenous insulin secretion was completely suppressed with SID, and the P/S-IG disappeared. Thus, compared with PID, an insulin clamp with SID underestimates the contribution of liver in response to insulin to whole body glucose flux. PMID:25516552

Insulin therapy for type 2 diabetes - are we there yet? The d-Nav® story.

PubMed

Hodish, I

2018-01-01

Insulin replacement therapy is mostly used by patients with type 2 diabetes who become insulin deficient and have failed other therapeutic options. They comprise about a quarter of those with diabetes, endures the majority of the complications and consumes the majority of the resources. Adequate insulin replacement therapy can prevent complications and reduce expenses, as long as therapy goals are achieved and maintained. Sadly, these therapy goals are seldom achieved and outcomes have not improved for decades despite advances in pharmacotherapy and technology. There is a growing recognition that the low success rate of insulin therapy results from intra-individual and inter-individual variations in insulin requirements. Total insulin requirements per day vary considerably between patients and constantly change without achieving a steady state. Thus, the key element in effective insulin therapy is unremitting and frequent dosage adjustments that can overcome those dynamics. In practice, insulin adjustments are done sporadically during outpatient clinic. Due to time constraints, providers are not able to deliver appropriate insulin dosage optimization. The d-Nav® Insulin Guidance Service has been developed to provide appropriate insulinization in insulin users without increasing the burden on healthcare systems. It relies on dedicated clinicians and a spectrum of technological solutions. Patients are provided with a handheld device called d-Nav® which advises them what dose of insulin to administer during each injection and automatically adjust insulin dosage when needed. The d-Nav care specialists periodically follow-up with users through telephone calls and in-person consultations to bestow user confidence, correct usage errors, triage, and identify uncharacteristic clinical courses. The following review provide details about the service and its clinical outcomes.

Orally administered H-Dmt-Tic-Lys-NH-CH2-Ph (MZ-2), a potent mu/delta-opioid receptor antagonist, regulates obese-related factors in mice.

PubMed

Marczak, Ewa D; Jinsmaa, Yunden; Myers, Page H; Blankenship, Terry; Wilson, Ralph; Balboni, Gianfranco; Salvadori, Severo; Lazarus, Lawrence H

2009-08-15

Orally active dual mu-/delta-opioid receptor antagonist, H-Dmt-Tic-Lys-NH-CH(2)-Ph (MZ-2) was applied to study body weight gain, fat content, bone mineral density, serum insulin, cholesterol and glucose levels in female ob/ob (B6.V-Lep/J homozygous) and lean wild mice with or without voluntary exercise on wheels for three weeks, and during a two week post-treatment period under the same conditions. MZ-2 (10mg/kg/day, p.o.) exhibited the following actions: (1) reduced body weight gain in sedentary obese mice that persisted beyond the treatment period without effect on lean mice; (2) stimulated voluntary running on exercise wheels of both groups of mice; (3) decreased fat content, enhanced bone mineral density (BMD), and decreased serum insulin and glucose levels in obese mice; and (4) MZ-2 (30 microM) increased BMD in human osteoblast cells (MG-63) comparable to naltrexone, while morphine inhibited mineral nodule formation. Thus, MZ-2 has potential application in the clinical management of obesity, insulin and glucose levels, and the amelioration of osteoporosis.

Cost-effectiveness of sensor-augmented pump therapy in two different patient populations with type 1 diabetes in Italy.

PubMed

Nicolucci, A; Rossi, M C; D'Ostilio, D; Delbaere, A; de Portu, S; Roze, S

2018-07-01

Sensor-augmented pump therapy (SAP) combines real time continuous glucose monitoring (CGM) with Continuous Subcutaneous Insulin Infusion (CSII) and provides additional benefits beyond those provided by CSII alone. SAP with automated insulin suspension provides early warning of the onset of hyperglycemia and hypoglycemia and has the functionality to suspend insulin delivery if sensor glucose levels are predicted to fall below a predefined threshold. Aim of this study was to assess the cost-effectiveness of SAP with automated insulin suspension versus CSII alone in type 1 diabetes. Cost-effectiveness analysis was performed using the CORE Diabetes Model. The analysis was performed in two different cohorts: one with high baseline HbA1c and one at elevated risk for hypoglycemic events. Clinical input data were sourced from published data. The analysis was conducted from a societal perspective over a lifetime time horizon; costs and clinical outcomes were discounted at 3% per year. In patients with poor glycemic control, SAP with automated insulin suspension resulted in improved discounted quality-adjusted life expectancy (QALY) versus CSII (12.44 QALYs vs. 10.99 QALYs) but higher mean total lifetime costs (€324,991 vs. €259,852), resulting in an incremental cost effectiveness ratio (ICER) of €44,982 per QALY gained. In patients at elevated risk for hypoglycemia, the ICER was €33,692 per QALY gained for SAP versus CSII. In Italy, the use of SAP with automated insulin suspension is associated with projected improvements in outcomes as compared to CSII. These benefits translate into an ICER usually considered as good value for money, particularly in patients at elevated risk of hypoglycemia. Copyright © 2018 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.

Long-Term Cost-Effectiveness of Insulin Glargine Versus Neutral Protamine Hagedorn Insulin for Type 2 Diabetes in Thailand.

PubMed

Permsuwan, Unchalee; Chaiyakunapruk, Nathorn; Dilokthornsakul, Piyameth; Thavorn, Kednapa; Saokaew, Surasak

2016-06-01

Even though Insulin glargine (IGlar) has been available and used in other countries for more than a decade, it has not been adopted into Thai national formulary. This study aimed to evaluate the long-term cost effectiveness of IGlar versus neutral protamine Hagedorn (NPH) insulin in type 2 diabetes from the perspective of Thai Health Care System. A validated computer simulation model (the IMS CORE Diabetes Model) was used to estimate the long-term projection of costs and clinical outcomes. The model was populated with published characteristics of Thai patients with type 2 diabetes. Baseline risk factors were obtained from Thai cohort studies, while relative risk reduction was derived from a meta-analysis study conducted by the Canadian Agency for Drugs and Technology in Health. Only direct costs were taken into account. Costs of diabetes management and complications were obtained from hospital databases in Thailand. Both costs and outcomes were discounted at 3 % per annum and presented in US dollars in terms of 2014 dollar value. Incremental cost-effectiveness ratio (ICER) was calculated. One-way and probabilistic sensitivity analyses were also performed. IGlar is associated with a slight gain in quality-adjusted life years (0.488 QALYs), an additional life expectancy (0.677 life years), and an incremental cost of THB119,543 (US$3522.19) compared with NPH insulin. The ICERs were THB244,915/QALY (US$7216.12/QALY) and THB176,525/life-year gained (LYG) (US$5201.09/LYG). The ICER was sensitive to discount rates and IGlar cost. At the acceptable willingness to pay of THB160,000/QALY (US$4714.20/QALY), the probability that IGlar was cost effective was less than 20 %. Compared to treatment with NPH insulin, treatment with IGlar in type 2 diabetes patients who had uncontrolled blood glucose with oral anti-diabetic drugs did not represent good value for money at the acceptable threshold in Thailand.

Loss of ovarian function in the VCD mouse-model of menopause leads to insulin resistance and a rapid progression into the metabolic syndrome.

PubMed

Romero-Aleshire, Melissa J; Diamond-Stanic, Maggie K; Hasty, Alyssa H; Hoyer, Patricia B; Brooks, Heddwen L

2009-09-01

Factors comprising the metabolic syndrome occur with increased incidence in postmenopausal women. To investigate the effects of ovarian failure on the progression of the metabolic syndrome, female B(6)C(3)F(1) mice were treated with 4-vinylcyclohexene diepoxide (VCD) and fed a high-fat (HF) diet for 16 wk. VCD destroys preantral follicles, causing early ovarian failure and is a well-characterized model for the gradual onset of menopause. After 12 wk on a HF diet, VCD-treated mice had developed an impaired glucose tolerance, whereas cycling controls were unaffected [12 wk AUC HF mice 13,455 +/- 643 vs. HF/VCD 17,378 +/- 1140 mg/dl/min, P < 0.05]. After 16 wk on a HF diet, VCD-treated mice had significantly higher fasting insulin levels (HF 5.4 +/- 1.3 vs. HF/VCD 10.1 +/- 1.4 ng/ml, P < 0.05) and were significantly more insulin resistant (HOMA-IR) than cycling controls on a HF diet (HF 56.2 +/- 16.7 vs. HF/VCD 113.1 +/- 19.6 mg/dl x microU/ml, P < 0.05). All mice on a HF diet gained more weight than mice on a standard diet, and weight gain in HF/VCD mice was significantly increased compared with HF cycling controls. Interestingly, even without a HF diet, progression into VCD-induced menopause caused a significant increase in cholesterol and free fatty acids. Furthermore, in mice fed a standard diet (6% fat), insulin resistance developed 4 mo after VCD-induced ovarian failure. Insulin resistance following ovarian failure (menopause) was prevented by estrogen replacement. Studies here demonstrate that ovarian failure (menopause) accelerates progression into the metabolic syndrome and that estrogen replacement prevents the onset of insulin resistance in VCD-treated mice. Thus, the VCD model of menopause provides a physiologically relevant means of studying how sex hormones influence the progression of the metabolic syndrome.

Experimentally induced gestational androgen excess disrupts glucoregulation in rhesus monkey dams and their female offspring.

PubMed

Abbott, David H; Bruns, Cristin R; Barnett, Deborah K; Dunaif, Andrea; Goodfriend, Theodore L; Dumesic, Daniel A; Tarantal, Alice F

2010-11-01

Discrete fetal androgen excess during early gestation in rhesus monkeys (Macaca mulatta) promotes endocrine antecedents of adult polycystic ovary syndrome (PCOS)-like traits in female offspring. Because developmental changes promoting such PCOS-like metabolic dysfunction remain unclear, the present study examined time-mated, gravid rhesus monkeys with female fetuses, of which nine gravid females received 15 mg of testosterone propionate (TP) subcutaneously daily from 40 to 80 days (first to second trimesters) of gestation [term, mean (range): 165 (155-175) days], whereas an additional six such females received oil vehicle injections over the same time interval. During gestation, ultrasonography quantified fetal growth measures and was used as an adjunct for fetal blood collections. At term, all fetuses were delivered by cesarean section for postnatal studies. Blood samples were collected from dams and infants for glucose, insulin, and total free fatty acid (FFA) determinations. TP injections transiently accelerated maternal weight gain in dams, very modestly increased head diameter of prenatally androgenized (PA) fetuses, and modestly increased weight gain in infancy compared with concurrent controls. Mild to moderate glucose intolerance, with increased area-under-the-curve circulating insulin values, occurred in TP-injected dams during an intravenous glucose tolerance test in the early second trimester. Moreover, reduced circulating FFA levels occurred in PA fetuses during a third trimester intravenous glucagon-tolbutamide challenge (140 days gestation), whereas excessive insulin sensitivity and increased insulin secretion relative to insulin sensitivity occurred in PA infants during an intravenous glucose-tolbutamide test at ∼1.5 mo postnatal age. Data from these studies suggest that experimentally induced fetal androgen excess may result in transient hyperglycemic episodes in the intrauterine environment that are sufficient to induce relative increases in pancreatic function in PA infants, suggesting in this nonhuman primate model that differential programming of insulin action and secretion may precede adult metabolic dysfunction.

Experimentally induced gestational androgen excess disrupts glucoregulation in rhesus monkey dams and their female offspring

PubMed Central

Bruns, Cristin R.; Barnett, Deborah K.; Dunaif, Andrea; Goodfriend, Theodore L.; Dumesic, Daniel A.; Tarantal, Alice F.

2010-01-01

Discrete fetal androgen excess during early gestation in rhesus monkeys (Macaca mulatta) promotes endocrine antecedents of adult polycystic ovary syndrome (PCOS)-like traits in female offspring. Because developmental changes promoting such PCOS-like metabolic dysfunction remain unclear, the present study examined time-mated, gravid rhesus monkeys with female fetuses, of which nine gravid females received 15 mg of testosterone propionate (TP) subcutaneously daily from 40 to 80 days (first to second trimesters) of gestation [term, mean (range): 165 (155–175) days], whereas an additional six such females received oil vehicle injections over the same time interval. During gestation, ultrasonography quantified fetal growth measures and was used as an adjunct for fetal blood collections. At term, all fetuses were delivered by cesarean section for postnatal studies. Blood samples were collected from dams and infants for glucose, insulin, and total free fatty acid (FFA) determinations. TP injections transiently accelerated maternal weight gain in dams, very modestly increased head diameter of prenatally androgenized (PA) fetuses, and modestly increased weight gain in infancy compared with concurrent controls. Mild to moderate glucose intolerance, with increased area-under-the-curve circulating insulin values, occurred in TP-injected dams during an intravenous glucose tolerance test in the early second trimester. Moreover, reduced circulating FFA levels occurred in PA fetuses during a third trimester intravenous glucagon-tolbutamide challenge (140 days gestation), whereas excessive insulin sensitivity and increased insulin secretion relative to insulin sensitivity occurred in PA infants during an intravenous glucose-tolbutamide test at ∼1.5 mo postnatal age. Data from these studies suggest that experimentally induced fetal androgen excess may result in transient hyperglycemic episodes in the intrauterine environment that are sufficient to induce relative increases in pancreatic function in PA infants, suggesting in this nonhuman primate model that differential programming of insulin action and secretion may precede adult metabolic dysfunction. PMID:20682841

Health economics analysis of insulin aspart vs. regular human insulin in type 2 diabetes patients, based on observational real life evidence from general practices in Germany.

PubMed

Liebl, A; Seitz, L; Palmer, A J

2014-10-01

A retrospective analysis of German general practice data demonstrated that insulin aspart (IA) was associated with a significantly reduced incidence of macrovascular events (MVE: stroke, myocardial infarction, peripheral vascular disease or coronary heart disease) vs. regular human insulin (RHI) in type 2 diabetes patients. Economic implications, balanced against potential improvements in quality-adjusted life years (QALYs) resulting from lower risks of complications with IA in this setting have not yet been explored. A decision analysis model was developed utilizing 3-year initial MVE rates for each comparator, combined with published German-specific insulin and MVE costs and health utilities to calculate number needed to treat (NNT) to avoid any MVE, incremental costs and QALYs gained/ person for IA vs. RHI. A 3-year time horizon and German 3(rd)-party payer perspective were used. Probabilistic sensitivity analysis was performed, sampling from distributions of key parameters. Additional sensitivity analyses were performed. NNT over a 3 year period to avoid any MVE was 8 patients for IA vs. RHI. Due to lower MVE rates, IA dominated RHI with 0.020 QALYs gained (95% confidence interval: 0.014-0.025) and cost savings of EUR 1 556 (1 062-2 076)/person for IA vs. RHI over the 3-year time horizon. Sensitivity analysis revealed that IA would still be overall cost saving even if the cost of IA was double the cost/unit of RHI. From a health economics perspective, IA was the superior alternative for the insulin treatment of type 2 diabetes, with lower incidence of MVE events translating to improved QALYs and lower costs vs. RHI within a 3-year time horizon. © J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart · New York.

Therapeutic actions of an insulin receptor activator and a novel peroxisome proliferator-activated receptor gamma agonist in the spontaneously hypertensive obese rat model of metabolic syndrome X.

PubMed

Velliquette, Rodney A; Friedman, Jacob E; Shao, J; Zhang, Bei B; Ernsberger, Paul

2005-07-01

Insulin resistance clusters with hyperlipidemia, impaired glucose tolerance, and hypertension as metabolic syndrome X. We tested a low molecular weight insulin receptor activator, demethylasterriquinone B-1 (DMAQ-B1), and a novel indole peroxisome proliferator-activated receptor gamma agonist, 2-(2-(4-phenoxy-2-propylphenoxy)ethyl)indole-5-acetic acid (PPEIA), in spontaneously hypertensive obese rats (SHROB), a genetic model of syndrome X. Agents were given orally for 19 days. SHROB showed fasting normoglycemia but impaired glucose tolerance after an oral load, as shown by increased glucose area under the curve (AUC) [20,700 mg x min/ml versus 8100 in lean spontaneously hypertensive rats (SHR)]. Insulin resistance was indicated by 20-fold excess fasting insulin and increased insulin AUC (6300 ng x min/ml versus 990 in SHR). DMAQ-B1 did not affect glucose tolerance (glucose AUC = 21,300) but reduced fasting insulin 2-fold and insulin AUC (insulin AUC = 4300). PPEIA normalized glucose tolerance (glucose AUC = 9100) and reduced insulin AUC (to 3180) without affecting fasting insulin. PPEIA also increased food intake, fat mass, and body weight gain (81 +/- 12 versus 45 +/- 8 g in untreated controls), whereas DMAQ-B1 had no effect on body weight but reduced subscapular fat mass. PPEIA but not DMAQ-B1 reduced blood pressure. In skeletal muscle, insulin-stimulated phosphorylation of the insulin receptor and insulin receptor substrate protein 1-associated phosphatidylinositol 3-kinase activity were decreased by 40 to 55% in SHROB relative to lean SHR. PPEIA, but not DMAQ-B1, enhanced both insulin actions. SHROB also showed severe hypertriglyceridemia (355 +/- 42 mg/dl versus 65 +/- 3 in SHR) attenuated by both agents (DMAQ-B1, 228 +/- 18; PPEIA, 79 +/- 3). Both these novel antidiabetic agents attenuate insulin resistance and hypertriglyceridemia associated with metabolic syndrome but via distinct mechanisms.

Who gains clinical benefit from using insulin pump therapy? A qualitative study of the perceptions and views of health professionals involved in the Relative Effectiveness of Pumps over MDI and Structured Education (REPOSE) trial.

PubMed

Lawton, J; Kirkham, J; Rankin, D; White, D A; Elliott, J; Jaap, A; Smithson, W H; Heller, S

2016-02-01

To explore health professionals' views about insulin pump therapy [continuous subcutaneous insulin infusion (CSII)] and the types of individuals they thought would gain greatest clinical benefit from using this treatment. In-depth interviews with staff (n = 18) who delivered the Relative Effectiveness of Pumps Over MDI and Structured Education (REPOSE) trial. Data were analysed thematically. Staff perceived insulin pumps as offering a better self-management tool to some individuals due to the drip feed of insulin, the ability to alter basal rates and other advanced features. However, staff also noted that, because of the diversity of features on offer, CSII is a more technically complex therapy to execute than multiple daily injections. For this reason, staff described how, alongside clinical criteria, they had tended to select individuals for CSII in routine clinical practice based on their perceptions about whether they possessed the personal and psychological attributes needed to make optimal use of pump technology. Staff also described how their assumptions about personal and psychological suitability had been challenged by working on the REPOSE trial and observing individuals make effective use of CSII who they would not have recommended for this type of therapy in routine clinical practice. Our findings add to those studies that highlight the difficulties of using patient characteristics and variables to predict clinical success using CSII. To promote equitable access to CSII, attitudinal barriers and prejudicial assumptions amongst staff about who is able to make effective use of CSII may need to be addressed. © 2015 The Authors. Diabetic Medicine © 2015 Diabetes UK.

Interplay between gut microbiota and p66Shc affects obesity-associated insulin resistance.

PubMed

Ciciliot, Stefano; Albiero, Mattia; Campanaro, Stefano; Poncina, Nicol; Tedesco, Serena; Scattolini, Valentina; Dalla Costa, Francesca; Cignarella, Andrea; Vettore, Monica; Di Gangi, Iole Maria; Bogialli, Sara; Avogaro, Angelo; Fadini, Gian Paolo

2018-02-21

The 66 kDa isoform of the mammalian Shc gene promotes adipogenesis, and p66Shc -/- mice accumulate less body weight than wild-type (WT) mice. As the metabolic consequences of the leaner phenotype of p66Shc -/- mice is debated, we hypothesized that gut microbiota may be involved. We confirmed that p66Shc -/- mice gained less weight than WT mice when on a high-fat diet (HFD), but they were not protected from insulin resistance and glucose intolerance. p66Shc deletion significantly modified the composition of gut microbiota and their modification after an HFD. This was associated with changes in gene expression of Il-1b and regenerating islet-derived protein 3 γ ( Reg3g) in the gut and in systemic trimethylamine N-oxide and branched chain amino acid levels, despite there being no difference in intestinal structure and permeability. Depleting gut microbiota at the end of HFD rendered both strains more glucose tolerant but improved insulin sensitivity only in p66Shc -/- mice. Microbiota-depleted WT mice cohoused with microbiota-competent p66Shc -/- mice became significantly more insulin resistant than WT mice cohoused with WT mice, despite no difference in weight gain. These findings reconcile previous inconsistent observations on the metabolic phenotype of p66Shc -/- mice and illustrate the complex microbiome-host-genotype interplay under metabolic stress.-Ciciliot, S., Albiero, M., Campanaro, S., Poncina, N., Tedesco, S., Scattolini, V., Dalla Costa, F., Cignarella, A., Vettore, M., Di Gangi, I. M., Bogialli, S., Avogaro, A., Fadini, G. P. Interplay between gut microbiota and p66Shc affects obesity-associated insulin resistance.

A unified Hyperglycemia and Diabetic ketoacidosis (DKA) insulin infusion protocol based on an Excel algorithm and implemented via Electronic Medical Record (EMR) in Intensive Care Units.

PubMed

Gupta, Deepashree; Kirn, Meredith; Jamkhana, Zafar A; Lee, Richard; Albert, Stewart G; Rollins, Kimberly M

To assess the efficacy of a unified hyperglycemia and diabetic ketoacidosis (DKA) insulin infusion protocol (IIP), based on an Excel algorithm and implemented as an electronic order set, in achieving glycemic targets and minimizing hypoglycemia. An IIP was instituted in medical and surgical intensive care units for post-cardiac surgery (PCS) and other stress hyperglycemia (SH), diabetes hyperglycemia (DH), and DKA. The IIP initiated therapeutic insulin rates at elevated blood glucose (BG), and decreased insulin when target range was achieved. A convenience sample (n=62) was studied; 20 PCS, 15 with DH, 9 with SH, 8 with diabetes on vasopressors, 7 with diabetes on glucocorticoids and 3 with DKA were assessed. The protocol maintained BG at 144±24.7mg/dL for PCS and 167±36mg/dL for patients with diabetes mellitus. It maintained acceptable target range (ATR) (100mg/dL-180mg/dL) 89% of the time for PCS and 67% of the time for patients with diabetes mellitus. There were no measurements of BG<70mg/dL. The protocol lowered the BG at a similar rate and time period in those with diabetes, DKA and those with or without vasopressors or glucocorticoids. To determine long-term efficacy, a retrospective review of Point of Care (POC) RALS (Remote Automated Data System) BG data 2 years post implementation demonstrated fewer episodes of hypoglycemia<70mg/dL and hyperglycemia>240mg/dL and more BG values within ATR. This IIP maintained ATR without hypoglycemia for patients in the ICU setting without requiring complex nursing calculations. Copyright © 2016 Diabetes India. Published by Elsevier Ltd. All rights reserved.

Comparison of Subcutaneous Regular Insulin and Lispro Insulin in Diabetics Receiving Continuous Nutrition

PubMed Central

Stull, Mamie C.; Strilka, Richard J.; Clemens, Michael S.; Armen, Scott B.

2015-01-01

Background: Optimal management of non–critically ill patients with diabetes maintained on continuous enteral feeding (CEN) is poorly defined. Subcutaneous (SQ) lispro and SQ regular insulin were compared in a simulated type 1 and type 2 diabetic patient receiving CEN. Method: A glucose-insulin feedback mathematical model was employed to simulate type 1 and type 2 diabetic patients on CEN. Each patient received 25 SQ injections of regular insulin or insulin lispro, ranging from 0-6 U. Primary endpoints were the change in mean glucose concentration (MGC) and change in glucose variability (GV); hypoglycemic episodes were also reported. The model was first validated against patient data. Results: Both SQ insulin preparations linearly decreased MGC, however, SQ regular insulin decreased GV whereas SQ lispro tended to increase GV. Hourly glucose concentration measurements were needed to capture the increase in GV. In the type 2 diabetic patient, “rebound hyperglycemia” occurred after SQ lispro was rapidly metabolized. Although neither SQ insulin preparation caused hypoglycemia, SQ lispro significantly lowered MGC compared to SQ regular insulin. Thus, it may be more likely to cause hypoglycemia. Analyses of the detailed glucose concentration versus time data suggest that the inferior performance of lispro resulted from its shorter duration of action. Finally, the effects of both insulin preparations persisted beyond their duration of actions in the type 2 diabetic patient. Conclusions: Subcutaneous regular insulin may be the short-acting insulin preparation of choice for this subset of diabetic patients. Clinical trial is required before a definitive recommendation can be made. PMID:26134836

Comparison of Subcutaneous Regular Insulin and Lispro Insulin in Diabetics Receiving Continuous Nutrition: A Numerical Study.

PubMed

Stull, Mamie C; Strilka, Richard J; Clemens, Michael S; Armen, Scott B

2015-06-30

Optimal management of non-critically ill patients with diabetes maintained on continuous enteral feeding (CEN) is poorly defined. Subcutaneous (SQ) lispro and SQ regular insulin were compared in a simulated type 1 and type 2 diabetic patient receiving CEN. A glucose-insulin feedback mathematical model was employed to simulate type 1 and type 2 diabetic patients on CEN. Each patient received 25 SQ injections of regular insulin or insulin lispro, ranging from 0-6 U. Primary endpoints were the change in mean glucose concentration (MGC) and change in glucose variability (GV); hypoglycemic episodes were also reported. The model was first validated against patient data. Both SQ insulin preparations linearly decreased MGC, however, SQ regular insulin decreased GV whereas SQ lispro tended to increase GV. Hourly glucose concentration measurements were needed to capture the increase in GV. In the type 2 diabetic patient, "rebound hyperglycemia" occurred after SQ lispro was rapidly metabolized. Although neither SQ insulin preparation caused hypoglycemia, SQ lispro significantly lowered MGC compared to SQ regular insulin. Thus, it may be more likely to cause hypoglycemia. Analyses of the detailed glucose concentration versus time data suggest that the inferior performance of lispro resulted from its shorter duration of action. Finally, the effects of both insulin preparations persisted beyond their duration of actions in the type 2 diabetic patient. Subcutaneous regular insulin may be the short-acting insulin preparation of choice for this subset of diabetic patients. Clinical trial is required before a definitive recommendation can be made. © 2015 Diabetes Technology Society.

PPAR delta: a dagger in the heart of the metabolic syndrome.

PubMed

Barish, Grant D; Narkar, Vihang A; Evans, Ronald M

2006-03-01

Obesity is a growing threat to global health by virtue of its association with insulin resistance, glucose intolerance, hypertension, and dyslipidemia, collectively known as the metabolic syndrome or syndrome X. The nuclear receptors PPARalpha and PPARgamma are therapeutic targets for hypertriglyceridemia and insulin resistance, respectively, and drugs that modulate these receptors are currently in clinical use. More recent work on the less-described PPAR isotype PPARdelta has uncovered a dual benefit for both hypertriglyceridemia and insulin resistance, highlighting the broad potential of PPARdelta in the treatment of metabolic disease. PPARdelta enhances fatty acid catabolism and energy uncoupling in adipose tissue and muscle, and it suppresses macrophage-derived inflammation. Its combined activities in these and other tissues make it a multifaceted therapeutic target for the metabolic syndrome with the potential to control weight gain, enhance physical endurance, improve insulin sensitivity, and ameliorate atherosclerosis.

New Insulin Glargine 300 Units/mL Versus Glargine 100 Units/mL in People With Type 1 Diabetes: A Randomized, Phase 3a, Open-Label Clinical Trial (EDITION 4).

PubMed

Home, Philip D; Bergenstal, Richard M; Bolli, Geremia B; Ziemen, Monika; Rojeski, Maria; Espinasse, Melanie; Riddle, Matthew C

2015-12-01

Insulin therapy in type 1 diabetes still provides suboptimal outcomes. Insulin glargine 300 units/mL (Gla-300), with a flatter pharmacodynamic profile compared with insulin glargine 100 units/mL (Gla-100), is an approach to this problem. People with type 1 diabetes, using a mealtime and basal insulin regimen, were randomized open-label to Gla-300 or Gla-100 and to morning or evening injection, continuing the mealtime analog, and followed for 6 months. Participants (n = 549) were a mean age of 47 years and had a mean duration of diabetes of 21 years and BMI of 27.6 kg/m(2). The change in HbA1c (primary end point; baseline 8.1%) was equivalent in the two treatment groups (difference, 0.04% [95% CI -0.10 to 0.19]) (0.4 mmol/mol [-1.1 to 2.1]), and Gla-300 was thus noninferior. Similar results with wider 95% CIs were found for morning and evening injection times and for prebreakfast self-measured plasma glucose (SMPG) overall. Results were also similar for Gla-300 when morning and evening injection time was compared, including overlapping 8-point SMPG profiles. Hypoglycemia did not differ, except for the first 8 weeks of the study, when nocturnal confirmed or severe hypoglycemia was lower with Gla-300 (rate ratio 0.69 [95% CI 0.53-0.91]). Hypoglycemia with Gla-300 did not differ by time of injection. The basal insulin dose was somewhat higher at 6 months for Gla-300. The adverse event profile did not differ and was independent of the Gla-300 time of injection. Weight gain was lower with Gla-300. In long-duration type 1 diabetes, Gla-300 provides similar glucose control to Gla-100, with a lower risk of hypoglycemia after transfer from other insulins, independent of time of injection, and less weight gain. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

Effects of Insulin and Octreotide on Memory and Growth Hormone in Alzheimer's Disease

PubMed Central

Watson, G. Stennis; Baker, Laura D.; Cholerton, Brenna A.; Rhoads, Kristoffer W.; Merriam, George R.; Schellenberg, Gerard D.; Asthana, PhD;Sanjay; Cherrier, Monique; Craft, Suzanne

2009-01-01

Both insulin alone and the somatostatin analogue octreotide alone facilitate memory in patients with Alzheimer's disease (AD). Since octreotide inhibits endogenous insulin secretion, the cognitive effects of insulin and octreotide may not be independent. This study tested the individual and interactive effects of insulin and octreotide on memory and plasma growth hormone (GH) levels in older adults. Participants were 16 memory-impaired (AD=7, amnestic mild cognitive impairment=9; apolipoprotein E [APOE] ε4- [no ε4 alleles]=9, ε4+ [1-2 ε4 alleles]=7) and 19 cognitively-intact older adults (APOE ε4-=17, ε4+=1). On separate days, fasting participants received counterbalanced infusions of (1) insulin (1 mU·kg-1·min-1) and dextrose to maintain euglycemia, (2) octreotide (150 μg/h), (3) insulin, dextrose, and octreotide, or (4) saline. Story recall was the principal endpoint. Insulin alone facilitated delayed recall for ε4-patients, relative to ε4+ patients (P=0.0012). Furthermore, ε4- patients with higher Mattis Dementia Rating Scale (DRS) scores had greater octreotide-induced memory facilitation (P=0.0298). For healthy adults, octreotide facilitated memory (P=0.0122). Unexpectedly, hyperinsulinemia with euglycemia increased GH levels in healthy controls (P=0.0299). Thus, insulin and octreotide appear to regulate memory in older adults. APOE ε4 genotype modulates responses to insulin and octreotide. Finally, insulin may regulate GH levels during euglycemia. PMID:19625744

Add on Exenatide Treatment is Beneficial in Poorly Controlled Obese Type 2 Diabetics under Intensive Insulin Regimens.

PubMed

Sönmez, Alper; Dinç, Mustafa; Taşlıpınar, Abdullah; Aydoğdu, Aydogan; Meriç, Coskun; Başaran, Yalcin; Haymana, Cem; Demir, Orhan; Yılmaz, İlker; Azal, Ömer

2017-04-01

Background: Intensive insulin treatment is bothersome in obese patients with type 2 diabetes mellitus. High insulin dosages further increase weight gain and the risk of hypoglycemia. Glucagon like peptide-1 receptor agonists decrease the insulin need, cause weight loss and reduce the risk of hypoglycemia. There is limited data about the effect of exenatide on obese diabetics under intensive insulin regimens. Methods: This retrospective case series report the clinical outcomes of 23 obese (13 morbidly obese) patients with uncontrolled type 2 diabetes mellitus (Age=59±10.44 years, body mass index 41.1±6.8 kg/m 2 , HbA1c 9.9±1.5%), under high dose (94.1±39.6 unit) intensive insulin. Exenatide twice daily was added for a mean follow-up period of 11.22±7.01 (3-30) months. Intensive insulin regimens were continued in 7 patients while the others were switched to basal insulin during the follow-up. Results: During the follow-up, mean HbA1c levels of the patients significantly improved (p=0.019), along with the significant decrease in body mass index and the total insulin need (p<0.001 for both). Baseline insulin dosages were significantly higher in the intensive regimen group (p=0.013) while other demographical and clinical characteristics were similar. No significant difference was present between the groups regarding the alterations of HbA1c, body mass index and the reduction in total insulin dosages. Conclusion: Add on exenatide appears to be a rational treatment modality in uncontrolled obese patients with type 2 diabetes mellitus despite intensive insulin regimens. Further prospective randomized studies with longer follow-up periods are recommended. © Georg Thieme Verlag KG Stuttgart · New York.

Predictors of increasing BMI during the course of diabetes in children and adolescents with type 1 diabetes: data from the German/Austrian DPV multicentre survey.

PubMed

Fröhlich-Reiterer, Elke E; Rosenbauer, Joachim; Bechtold-Dalla Pozza, Susanne; Hofer, Sabine E; Schober, Edith; Holl, Reinhard W

2014-08-01

Increased weight gain has been reported prior to disease onset (accelerator hypothesis) and as a side effect of intensified insulin therapy in type 1 diabetes (T1D). Paediatric studies are complicated by the age-dependency and gender-dependency of BMI, and also by a trend towards obesity in the general population. The aim of this study was to evaluate factors related to the increase in BMI during the course of diabetes in children and adolescents with T1D in a large multicentre survey. Within the DPV database (Diabetespatienten Verlaufsdokumentation) a standardised, prospective, computer-based documentation programme, data of 53,108 patients with T1D, aged <20 years, were recorded in 248 centres. 12,774 patients (53% male, mean age 13.4±3.9, mean diabetes duration 4.7±3.0 years and mean age at diabetes onset 8.7±4.0 years) were included in this analysis. Population-based German reference data were used to calculate BMI-SDS and define overweight and obesity. 12.5% of T1D patients were overweight and 2.8% were obese. Multiple longitudinal regression analysis revealed that female gender, low BMI at diabetes onset, intensified insulin therapy and higher insulin dose, as well as pubertal diabetes onset, long diabetes duration and onset in earlier calendar years among girls, were related to higher BMI-SDS increase during the course of diabetes (p<0.01; all). Intensified insulin regimen is associated with weight gain during T1D treatment, in addition to demographic variables. Optimisation of diabetes management, especially in females, might limit weight gain in order to reduce overweight and obesity together with comorbidities among paediatric T1D patients. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

The lysosomal membrane protein SCAV-3 maintains lysosome integrity and adult longevity

PubMed Central

Li, Yuan; Chen, Baohui; Zou, Wei; Wang, Xin; Wu, Yanwei; Zhao, Dongfeng; Sun, Yanan; Liu, Yubing

2016-01-01

Lysosomes degrade macromolecules and recycle metabolites as well as being involved in diverse processes that regulate cellular homeostasis. The lysosome is limited by a single phospholipid bilayer that forms a barrier to separate the potent luminal hydrolases from other cellular constituents, thus protecting the latter from unwanted degradation. The mechanisms that maintain lysosomal membrane integrity remain unknown. Here, we identified SCAV-3, the Caenorhabditis elegans homologue of human LIMP-2, as a key regulator of lysosome integrity, motility, and dynamics. Loss of scav-3 caused rupture of lysosome membranes and significantly shortened lifespan. Both of these phenotypes were suppressed by reinforced expression of LMP-1 or LMP-2, the C. elegans LAMPs, indicating that longevity requires maintenance of lysosome integrity. Remarkably, reduction in insulin/insulin-like growth factor 1 (IGF-1) signaling suppressed lysosomal damage and extended the lifespan in scav-3(lf) animals in a DAF-16–dependent manner. Our data reveal that SCAV-3 is essential for preserving lysosomal membrane stability and that modulation of lysosome integrity by the insulin/IGF-1 signaling pathway affects longevity. PMID:27810910

Converting adult pancreatic islet α-cells into β-cells by targeting both Dnmt1 and Arx

PubMed Central

Chakravarthy, Harini; Gu, Xueying; Enge, Martin; Dai, Xiaoqing; Wang, Yong; Damond, Nicolas; Downie, Carolina; Liu, Kathy; Wang, Jing; Xing, Yuan; Chera, Simona; Thorel, Fabrizio; Quake, Stephen; Oberholzer, Jose; MacDonald, Patrick E.; Herrera, Pedro L.; Kim, Seung K.

2017-01-01

Summary Insulin-producing pancreatic β-cells in mice can slowly regenerate from glucagon-producing α-cells in settings like β-cell loss, but the basis of this conversion is unknown. Moreover it remains unclear if this intra-islet cell conversion is relevant to diseases like type 1 diabetes (T1D). We show that the α-cell regulators Aristaless-related homeobox (Arx) and DNA methyltransferase 1 (Dnmt1) maintain α-cell identity in mice. Within 3 months of Dnmt1 and Arx loss, lineage tracing and single cell RNA sequencing revealed extensive α-cell conversion into progeny resembling native β-cells. Physiological studies demonstrated that converted α-cells acquire hallmark β-cell electrophysiology, and show glucose-stimulated insulin secretion. In T1D patients, subsets of Glucagon-expressing cells show loss of DNMT1 and ARX, and produce Insulin and other β-cell factors, suggesting that DNMT1 and ARX maintain α-cell identity in humans. Our work reveals pathways regulated by Arx and Dnmt1 sufficient for achieving targeted generation of β-cells from adult pancreatic α-cells. PMID:28215845

Insulin sensitivity and brain reward activation in overweight Hispanic girls: a pilot study

PubMed Central

Adam, Tanja C.; Tsao, Sinchai; Page, Kathleen A.; Hu, Houchun; Hasson, Rebecca E.; Goran, Michael I.

2014-01-01

Background Insulin resistance is a link between obesity and the associated disease risk. In addition to its role as an energy regulatory signal to the hypothalamus, insulin also modulates food reward. Objective To examine the relationship of insulin sensitivity (SI) and fasting insulin with cerebral activation in response to food and non-food cues in children. Methods Twelve overweight Hispanic girls (age: 8–11) participated in two study visits, a frequently sampled intravenous glucose tolerance test and a functional neuroimaging (fMRI) session (GE HDxt 3.0Tesla)) with visual stimulation tasks. Blocks of images (high calorie (HC), low calorie (LC) and non-food (NF)) were presented in randomized order. Results Comparing HC with NF, SI was inversely associated with activation in the anterior cingulate (r2 = 0.65; p < 0.05), the insula (r2 = 0.69; p < 0.05), the orbitofrontal cortex (r2 = 0.74; p < 0.05), and the frontal and rolandic operculum (r2 = 0.76; p < 0.001). Associations remained significant after adjustment for BMI. Association of fasting insulin and cerebral activation dissapeared after adjustment for waist circumference. Conclusion In addition to weight loss insulin sensitivity may pose an important target to regulate neural responses to food cues in the prevention of excessive weight gain. PMID:24357646

Insulin resistance in the control of body fat distribution: a new hypothesis.

PubMed

Ali, A T; Ferris, W F; Naran, N H; Crowther, N J

2011-02-01

Obesity causes insulin resistance, which is a prime etiological factor for type 2 diabetes, dyslipidemia, and cardiovascular disease. However, insulin resistance may be a normal physiological response to obesity that limits further fat deposition and which only has pathological effects at high levels. The current hypothesis suggests that in obesity the initial deposition of triglycerides occurs in subcutaneous adipose tissue and as this increases in size insulin resistance will rise and limit further subcutaneous lipid accumulation. Triglycerides will then be diverted to the visceral fat depot as well as to ectopic sites. This leads to a substantial rise in insulin resistance and the prevalence of its associated disorders. Evidence supporting this hypothesis includes studies showing that in lean subjects the prime determinant of insulin resistance is BMI, that is, subcutaneous fat whilst in overweight and obese subjects it is waist circumference and visceral adiposity. It has also been shown that the metabolic syndrome suddenly increases in prevalence at high levels of insulin resistance and we suggest that this is due to the diversion of lipids from the subcutaneous to the visceral depot. This system may have functioned in our evolutionary past to limit excessive adiposity by causing lipid deposition to occur at a site that has maximal effects on insulin resistance but involves minimal weight gain. © Georg Thieme Verlag KG Stuttgart · New York.

Skeletal Muscle TRIB3 Mediates Glucose Toxicity in Diabetes and High- Fat Diet–Induced Insulin Resistance

PubMed Central

Wu, Mengrui; Kim, Teayoun; Jariwala, Ravi H.; Garvey, W. John; Luo, Nanlan; Kang, Minsung; Ma, Elizabeth; Tian, Ling; Steverson, Dennis; Yang, Qinglin; Fu, Yuchang

2016-01-01

In the current study, we used muscle-specific TRIB3 overexpressing (MOE) and knockout (MKO) mice to determine whether TRIB3 mediates glucose-induced insulin resistance in diabetes and whether alterations in TRIB3 expression as a function of nutrient availability have a regulatory role in metabolism. In streptozotocin diabetic mice, TRIB3 MOE exacerbated, whereas MKO prevented, glucose-induced insulin resistance and impaired glucose oxidation and defects in insulin signal transduction compared with wild-type (WT) mice, indicating that glucose-induced insulin resistance was dependent on TRIB3. In response to a high-fat diet, TRIB3 MOE mice exhibited greater weight gain and worse insulin resistance in vivo compared with WT mice, coupled with decreased AKT phosphorylation, increased inflammation and oxidative stress, and upregulation of lipid metabolic genes coupled with downregulation of glucose metabolic genes in skeletal muscle. These effects were prevented in the TRIB3 MKO mice relative to WT mice. In conclusion, TRIB3 has a pathophysiological role in diabetes and a physiological role in metabolism. Glucose-induced insulin resistance and insulin resistance due to diet-induced obesity both depend on muscle TRIB3. Under physiological conditions, muscle TRIB3 also influences energy expenditure and substrate metabolism, indicating that the decrease and increase in muscle TRIB3 under fasting and nutrient excess, respectively, are critical for metabolic homeostasis. PMID:27207527

Intrauterine insulin resistance in fetuses of overweight mothers.

PubMed

Liu, Bin; Xu, Yun; Liang, Jian-Ming; Voss, Courtney; Xiao, Huan-Yu; Sheng, Wei-Yang; Sun, Yan-Hong; Wang, Zi-Lian

2013-01-01

To investigate the relationship between maternal overweight and fetal insulin resistance. Nineteen overweight and 30 lean pregnant women were recruited in the present study. Maternal and fetal insulin resistance were determined by measuring sex hormone binding globulin (SHBG) concentrations in maternal venous or umbilical cord serum, respectively. Maternal age, gestational age, height, pre-gravidity weight, pre-partum weight, as well as fetal gender, birth weight, birth height, and head circumference were collected as clinical data. Fetuses of overweight mothers had larger birth weight (3.58±0.55kg vs 3.32±0.42, adjusted P=0.006) and lower SHBG concentrations (26.64±3.65 vs 34.36±7.84, adjusted P=0.007) than those of lean mothers after values were adjusted for potential cofactors. Fetal SHBG level was negatively correlated with pre-gravidity body mass index (R=-0.392, adjusted P=0.025) and weight gain during pregnancy (R=-0.332, adjusted P=0.026) even with adjustment for potential cofactors. Among the 29 pregnant women with gestational diabetes mellitus, the overweight mothers had higher H1AC levels than their lean counterparts (6.47±0.44 vs 5.74±0.52, adjusted P=0.004). Intrauterine insulin resistance is more prominent in fetuses of overweight mothers, an effect that is decreased by weight gain control during pregnancy. © 2012 The Authors. Journal of Obstetrics and Gynaecology Research © 2012 Japan Society of Obstetrics and Gynecology.

Reversal of diet-induced obesity increases insulin transport into cerebrospinal fluid and restores sensitivity to the anorexic action of central insulin in male rats.

PubMed

Begg, Denovan P; Mul, Joram D; Liu, Min; Reedy, Brianne M; D'Alessio, David A; Seeley, Randy J; Woods, Stephen C

2013-03-01

Diet-induced obesity (DIO) reduces the ability of centrally administered insulin to reduce feeding behavior and also reduces the transport of insulin from the periphery to the central nervous system (CNS). The current study was designed to determine whether reversal of high-fat DIO restores the anorexic efficacy of central insulin and whether this is accompanied by restoration of the compromised insulin transport. Adult male Long-Evans rats were initially maintained on either a low-fat chow diet (LFD) or a high-fat diet (HFD). After 22 weeks, half of the animals on the HFD were changed to the LFD, whereas the other half continued on the HFD for an additional 8 weeks, such that there were 3 groups: 1) a LFD control group (Con; n = 18), 2) a HFD-fed, DIO group (n = 17), and 3) a HFD to LFD, DIO-reversal group (DIO-rev; n = 18). The DIO reversal resulted in a significant reduction of body weight and epididymal fat weight relative to the DIO group. Acute central insulin administration (8 mU) reduced food intake and caused weight loss in Con and DIO-rev but not DIO rats. Fasting cerebrospinal fluid insulin was higher in DIO than Con animals. However, after a peripheral bolus injection of insulin, cerebrospinal fluid insulin increased in Con and DIO-rev rats but not in the DIO group. These data provide support for previous reports that DIO inhibits both the central effects of insulin and insulin's transport to the CNS. Importantly, DIO-rev restored sensitivity to the effects of central insulin on food intake and insulin transport into the CNS.

The disposition index does not reflect β-cell function in IGT subjects treated with pioglitazone.

PubMed

DeFronzo, Ralph A; Tripathy, Devjit; Abdul-Ghani, Muhammad; Musi, Nicolas; Gastaldelli, Amalia

2014-10-01

The insulin secretion/insulin resistance (IR) (disposition) index (ΔI/ΔG ÷ IR, where Δ is change from baseline, I is insulin, and G is glucose) is commonly used as a measure of β-cell function. This relationship is curvilinear and becomes linear when log transformed. ΔI is determined by 2 variables: insulin secretion rate (ISR) and metabolic clearance of insulin. We postulated that the characteristic curvilinear relationship would be lost if Δ plasma C-peptide (ΔCP) (instead of Δ plasma insulin) was plotted against insulin sensitivity. A total of 441 individuals with impaired glucose tolerance (IGT) from ACT NOW received an oral glucose tolerance test and were randomized to pioglitazone or placebo for 2.4 years. Pioglitazone reduced IGT conversion to diabetes by 72% (P < .0001). ΔI/ΔG vs the Matsuda index of insulin sensitivity showed the characteristic curvilinear relationship. However, when ΔCP/ΔG or ΔISR/ΔG was plotted against the Matsuda index, the curvilinear relationship was completely lost. This discordance was explained by 2 distinct physiologic effects that altered plasma insulin response in opposite directions: 1) increased ISR and 2) augmented metabolic clearance of insulin. The net result was a decline in the plasma insulin response to hyperglycemia during the oral glucose tolerance test. These findings demonstrate a physiologic control mechanism wherein the increase in ISR ensures adequate insulin delivery into the portal circulation to suppress hepatic glucose production while delivering a reduced but sufficient amount of insulin to peripheral tissues to maintain the pioglitazone-mediated improvement in insulin sensitivity without excessive hyperinsulinemia. These results demonstrate the validity of the disposition index when relating the plasma insulin response to insulin sensitivity but underscore the pitfall of this index when drawing conclusions about β-cell function, because insulin secretion declined despite an increase in the plasma insulin response.

Enrichment, Distribution of Vanadium-Containing Protein in Vanadium-Enriched Sea Cucumber Apostichopus japonicus and the Ameliorative Effect on Insulin Resistance.

PubMed

Liu, Yanjun; Zhou, Qingxin; Zhao, Yanlei; Wang, Yiming; Wang, Yuming; Wang, Jingfeng; Xu, Jie; Xue, Changhu

2016-05-01

Sea cucumbers are a potential source of natural organic vanadium that may improve insulin resistance. In this work, vanadium was accumulated rapidly in blood, body wall, and intestine by sea cucumber Apostichopus japonicus. Furthermore, water-soluble vanadium-containing proteins, the main form of the organic vanadium, were tentatively accumulated and isolated by a bioaccumulation experiment. It was also designed to evaluate the beneficial effect of vanadium-containing proteins (VCPs) from sea cucumber rich in vanadium on the development of hyperglycemia and insulin resistance in C57BL/6J mice fed with a high-fat high-sucrose diet (HFSD). HFSD mice treated with VCPs significantly decreased fasting blood glucose, serum insulin, and HOMA-IR values as compared to HFSD mice, respectively. Serum adiponectin, resistin, TNF-α, and leptin levels in insulin-resistant mice were dramatically reduced by a VCP supplement. These results show an ameliorative effect on insulin resistance by treatment with VCPs. Such compound seems to be a valuable therapy to achieve and/or maintain glycemic control and therapeutic agents in the treatment arsenal for insulin resistance and type 2 diabetes.

Excessive weight gain during full breast-feeding.

PubMed

Grunewald, Maria; Hellmuth, Christian; Demmelmair, Hans; Koletzko, Berthold

2014-01-01

Breast-feeding is considered to offer optimal nutrition for healthy infant growth and development. Observational studies have linked breast-feeding to reduced obesity. CASE OBSERVATION: We observed an infant who was born macrosomic (4.56 kg) and showed excessive weight gain markedly exceeding the 97th percentile of weight during full breast-feeding. At the age of 4 months, the weight was greater than 11 kg. Clinical evaluation did not reveal any underlying pathology. After the introduction of complementary feeding and hence reduction of the breast milk intake, the excessive weight gain was attenuated and the slope of the percentile curve paralleled upper percentiles. Since this pattern suggested full breast-feeding as the driver of excessive weight gain, we analyzed the human milk composition at the infant age of 1 year and compared the results with published data on composition at this stage of lactation. The milk contents of lactose, fat, fatty acids, polar lipids, carnitine species, and insulin were similar to the reference data. The adiponectin content was increased. The most remarkable alteration was a high milk protein content (mean 1.25 g/dl, reference 0.8 g/dl). A very high protein supply in infancy has been previously shown to increase plasma concentrations of the growth factors insulin and IGF-1, weight gain, and later obesity. We speculate that interindividual variations in human milk adiponectin and protein contents may contribute to modulation of the growth of fully breast-fed infants and in this case may have contributed to excessive weight gain during full breast-feeding. This hypothesis merits being tested in future cohort studies. © 2014 S. Karger AG, Basel.

Silymarin Induces Insulin Resistance through an Increase of Phosphatase and Tensin Homolog in Wistar Rats

PubMed Central

Cheng, Kai-Chun; Asakawa, Akihiro; Li, Ying-Xiao; Chung, Hsien-Hui; Amitani, Haruka; Ueki, Takatoshi; Cheng, Juei-Tang; Inui, Akio

2014-01-01

Background and aims Phosphatase and tensin homolog (PTEN) is a phosphoinositide phosphatase that regulates crucial cellular functions, including insulin signaling, lipid and glucose metabolism, as well as survival and apoptosis. Silymarin is the active ingredient in milk thistle and exerts numerous effects through the activation of PTEN. However, the effect of silymarin on the development of insulin resistance remains unknown. Methods Wistar rats fed fructose-rich chow or normal chow were administered oral silymarin to identify the development of insulin resistance using the homeostasis model assessment of insulin resistance and hyperinsulinemic- euglycemic clamping. Changes in PTEN expression in skeletal muscle and liver were compared using western blotting analysis. Further investigation was performed in L6 cells to check the expression of PTEN and insulin-related signals. PTEN deletion in L6 cells was achieved by small interfering ribonucleic acid transfection. Results Oral administration of silymarin at a dose of 200 mg/kg once daily induced insulin resistance in normal rats and enhanced insulin resistance in fructose-rich chow-fed rats. An increase of PTEN expression was observed in the skeletal muscle and liver of rats with insulin resistance. A decrease in the phosphorylation of Akt in L6 myotube cells, which was maintained in a high-glucose condition, was also observed. Treatment with silymarin aggravated high-glucose-induced insulin resistance. Deletion of PTEN in L6 cells reversed silymarin-induced impaired insulin signaling and glucose uptake. Conclusions Silymarin has the ability to disrupt insulin signaling through increased PTEN expression. Therefore, silymarin should be used carefully in type-2 diabetic patients. PMID:24404172

Early growth response-1 negative feedback regulates skeletal muscle postprandial insulin sensitivity via activating Ptp1b transcription.

PubMed

Wu, Jing; Tao, Wei-Wei; Chong, Dan-Yang; Lai, Shan-Shan; Wang, Chuang; Liu, Qi; Zhang, Tong-Yu; Xue, Bin; Li, Chao-Jun

2018-03-15

Postprandial insulin desensitization plays a critical role in maintaining whole-body glucose homeostasis by avoiding the excessive absorption of blood glucose; however, the detailed mechanisms that underlie how the major player, skeletal muscle, desensitizes insulin action remain to be elucidated. Herein, we report that early growth response gene-1 ( Egr-1) is activated by insulin in skeletal muscle and provides feedback inhibition that regulates insulin sensitivity after a meal. The inhibition of the transcriptional activity of Egr-1 enhanced the phosphorylation of the insulin receptor (InsR) and Akt, thus increasing glucose uptake in L6 myotubes after insulin stimulation, whereas overexpression of Egr-1 decreased insulin sensitivity. Furthermore, deletion of Egr-1 in the skeletal muscle improved systemic insulin sensitivity and glucose tolerance, which resulted in lower blood glucose levels after refeeding. Mechanistic analysis demonstrated that EGR-1 inhibited InsR phosphorylation and glucose uptake in skeletal muscle by binding to the proximal promoter region of protein tyrosine phosphatase-1B (PTP1B) and directly activating transcription. PTP1B knockdown largely restored insulin sensitivity and enhanced glucose uptake, even under conditions of EGR-1 overexpression. Our results indicate that EGR-1/PTP1B signaling negatively regulates postprandial insulin sensitivity and suggest a potential therapeutic target for the prevention and treatment of excessive glucose absorption.-Wu, J., Tao, W.-W., Chong, D.-Y., Lai, S.-S., Wang, C., Liu, Q., Zhang, T.-Y., Xue, B., Li, C.-J. Early growth response-1 negative feedback regulates skeletal muscle postprandial insulin sensitivity via activating Ptp1b transcription.

Switching from high-fat to low-fat diet normalizes glucose metabolism and improves glucose-stimulated insulin secretion and insulin sensitivity but not body weight in C57BL/6J mice.

PubMed

Agardh, Carl-David; Ahrén, Bo

2012-03-01

Environmental factors such as a high-fat diet contribute to type 2 diabetes and obesity. This study examined glycemia, insulin sensitivity, and β-cell function after switching from a high-fat diet to a low-fat diet in mice. C57BL/6J mice were fed a high-fat diet or low-fat diet for 18 months, after which mice on the high-fat diet either maintained this diet or switched to a low-fat diet for 4 weeks. Body weight and glucose and insulin responses to intraperitoneal glucose were determined. Insulin secretion (insulinogenic index: the 10-minute insulin response divided by the 10-minute glucose level) and insulin sensitivity (1 divided by basal insulin) were determined. After 18 months on a high-fat diet, mice had glucose intolerance, marked hyperinsulinemia, and increased body weight compared to mice on a low-fat diet (P < 0.001). Switching from a high-fat diet to low-fat diet normalized glucose tolerance, reduced but not normalized body weight (P < 0.001), increased insulin secretion (248 ± 39 vs 141 ± 46 pmol/mmol; P = 0.028) and improved but not normalized insulin sensitivity (3.2 ± 0.1 vs 1.0 ± 0.1 [pmol/L]; P = 0.012). Switching from a high-fat diet to low-fat diet normalizes glucose tolerance and improves but not normalizes insulin secretion and insulin sensitivity. These effects are more pronounced than the reduced body weight.

Enhanced bone regeneration using an insulin-loaded nano-hydroxyapatite/collagen/PLGA composite scaffold.

PubMed

Wang, Xing; Zhang, Guilan; Qi, Feng; Cheng, Yongfeng; Lu, Xuguang; Wang, Lu; Zhao, Jing; Zhao, Bin

2018-01-01

Insulin is widely considered as a classical hormone and drug in maintaining energy and glucose homeostasis. Recently, insulin has been increasingly recognized as an indispensable factor for osteogenesis and bone turnover, but its applications in bone regeneration have been restricted because of the short periods of activity and uncontrolled release. In this study, we incorporated insulin-loaded poly lactic-co-glycolic-acid (PLGA) nanospheres into nano-hydroxyapatite/collagen (nHAC) scaffolds and investigated the bioactivity of the composite scaffolds in vitro and in vivo. Bioactive insulin was successfully released from the nanospheres within the scaffold, and the release kinetics of insulin could be efficiently controlled by uniform-sized nanospheres. The physical characterizations of the composite scaffolds demonstrated that incorporation of nanospheres in nHAC scaffolds using this method did not significantly change the porosity, pore diameters, and compressive strengths of nHAC. In vitro, the insulin-loaded nHAC/PLGA composite scaffolds possessed favorable biological function for bone marrow mesenchymal stem cells adhesion and proliferation, as well as the differentiation into osteoblasts. In vivo, the optimized bone regenerative capability of this composite scaffold was confirmed in rabbit mandible critical size defects. These results demonstrated successful development of a functional insulin-PLGA-nHAC composite scaffold that enhances the bone regeneration capability of nHAC.

Remission of Diabetes by Insulin Gene Therapy Using a Hepatocyte-specific and Glucose-responsive Synthetic Promoter

PubMed Central

Han, Jaeseok; McLane, Brienne; Kim, Eung-Hwi; Yoon, Ji-Won; Jun, Hee-Sook

2011-01-01

Efficient production of insulin in response to changes in glucose levels has been a major issue for insulin gene therapy to treat diabetes. To express target genes in response to glucose specifically in hepatocytes, we generated a synthetic promoter library containing hepatocyte nuclear factor-1, CAAT/enhancer-binding protein (C/EBP) response element, and glucose-response element. Combinations of these three cis-elements in 3-, 6-, or 9-element configurations were screened for transcriptional activity and then glucose responsiveness in vitro. The most effective promoter (SP23137) was selected for further study. Intravenous administration of a recombinant adenovirus expressing furin-cleavable rat insulin under control of the SP23137 promoter into streptozotocin (STZ)-induced diabetic mice resulted in normoglycemia, which was maintained for >30 days. Glucose tolerance tests showed that treated mice produced insulin in response to glucose and cleared exogenous glucose from the blood in a manner similar to nondiabetic control mice, although the clearance was somewhat delayed. Insulin expression was seen specifically in the liver and not in other organs. These observations indicate the potential of this synthetic, artificial promoter to regulate glucose-responsive insulin production and remit hyperglycemia, thus providing a new method of liver-directed insulin gene therapy for type 1 diabetes. PMID:21119621

Remission of diabetes by insulin gene therapy using a hepatocyte-specific and glucose-responsive synthetic promoter.

PubMed

Han, Jaeseok; McLane, Brienne; Kim, Eung-Hwi; Yoon, Ji-Won; Jun, Hee-Sook

2011-03-01

Efficient production of insulin in response to changes in glucose levels has been a major issue for insulin gene therapy to treat diabetes. To express target genes in response to glucose specifically in hepatocytes, we generated a synthetic promoter library containing hepatocyte nuclear factor-1, CAAT/enhancer-binding protein (C/EBP) response element, and glucose-response element. Combinations of these three cis-elements in 3-, 6-, or 9-element configurations were screened for transcriptional activity and then glucose responsiveness in vitro. The most effective promoter (SP23137) was selected for further study. Intravenous administration of a recombinant adenovirus expressing furin-cleavable rat insulin under control of the SP23137 promoter into streptozotocin (STZ)-induced diabetic mice resulted in normoglycemia, which was maintained for >30 days. Glucose tolerance tests showed that treated mice produced insulin in response to glucose and cleared exogenous glucose from the blood in a manner similar to nondiabetic control mice, although the clearance was somewhat delayed. Insulin expression was seen specifically in the liver and not in other organs. These observations indicate the potential of this synthetic, artificial promoter to regulate glucose-responsive insulin production and remit hyperglycemia, thus providing a new method of liver-directed insulin gene therapy for type 1 diabetes.

Myoblast replication is reduced in the IUGR fetus despite maintained proliferative capacity in vitro.

PubMed

Soto, Susan M; Blake, Amy C; Wesolowski, Stephanie R; Rozance, Paul J; Barthel, Kristen B; Gao, Bifeng; Hetrick, Byron; McCurdy, Carrie E; Garza, Natalia G; Hay, William W; Leinwand, Leslie A; Friedman, Jacob E; Brown, Laura D

2017-03-01

Adults who were affected by intrauterine growth restriction (IUGR) suffer from reductions in muscle mass and insulin resistance, suggesting muscle growth may be restricted by molecular events that occur during fetal development. To explore the basis of restricted fetal muscle growth, we used a sheep model of progressive placental insufficiency-induced IUGR to assess myoblast proliferation within intact skeletal muscle in vivo and isolated myoblasts stimulated with insulin in vitro Gastrocnemius and soleus muscle weights were reduced by 25% in IUGR fetuses compared to those in controls (CON). The ratio of PAX7+ nuclei (a marker of myoblasts) to total nuclei was maintained in IUGR muscle compared to CON, but the fraction of PAX7+ myoblasts that also expressed Ki-67 (a marker of cellular proliferation) was reduced by 23%. Despite reduced proliferation in vivo, fetal myoblasts isolated from IUGR biceps femoris and cultured in enriched media in vitro responded robustly to insulin in a dose- and time-dependent manner to increase proliferation. Similarly, insulin stimulation of IUGR myoblasts upregulated key cell cycle genes and DNA replication. There were no differences in the expression of myogenic regulatory transcription factors that drive commitment to muscle differentiation between CON and IUGR groups. These results demonstrate that the molecular machinery necessary for transcriptional control of proliferation remains intact in IUGR fetal myoblasts, indicating that in vivo factors such as reduced insulin and IGF1, hypoxia and/or elevated counter-regulatory hormones may be inhibiting muscle growth in IUGR fetuses. © 2017 Society for Endocrinology.

Targeting VEGF-B as a novel treatment for insulin resistance and type 2 diabetes.

PubMed

Hagberg, Carolina E; Mehlem, Annika; Falkevall, Annelie; Muhl, Lars; Fam, Barbara C; Ortsäter, Henrik; Scotney, Pierre; Nyqvist, Daniel; Samén, Erik; Lu, Li; Stone-Elander, Sharon; Proietto, Joseph; Andrikopoulos, Sofianos; Sjöholm, Ake; Nash, Andrew; Eriksson, Ulf

2012-10-18

The prevalence of type 2 diabetes is rapidly increasing, with severe socioeconomic impacts. Excess lipid deposition in peripheral tissues impairs insulin sensitivity and glucose uptake, and has been proposed to contribute to the pathology of type 2 diabetes. However, few treatment options exist that directly target ectopic lipid accumulation. Recently it was found that vascular endothelial growth factor B (VEGF-B) controls endothelial uptake and transport of fatty acids in heart and skeletal muscle. Here we show that decreased VEGF-B signalling in rodent models of type 2 diabetes restores insulin sensitivity and improves glucose tolerance. Genetic deletion of Vegfb in diabetic db/db mice prevented ectopic lipid deposition, increased muscle glucose uptake and maintained normoglycaemia. Pharmacological inhibition of VEGF-B signalling by antibody administration to db/db mice enhanced glucose tolerance, preserved pancreatic islet architecture, improved β-cell function and ameliorated dyslipidaemia, key elements of type 2 diabetes and the metabolic syndrome. The potential use of VEGF-B neutralization in type 2 diabetes was further elucidated in rats fed a high-fat diet, in which it normalized insulin sensitivity and increased glucose uptake in skeletal muscle and heart. Our results demonstrate that the vascular endothelium can function as an efficient barrier to excess muscle lipid uptake even under conditions of severe obesity and type 2 diabetes, and that this barrier can be maintained by inhibition of VEGF-B signalling. We propose VEGF-B antagonism as a novel pharmacological approach for type 2 diabetes, targeting the lipid-transport properties of the endothelium to improve muscle insulin sensitivity and glucose disposal.

Insulin Management Strategies for Exercise in Diabetes.

PubMed

Zaharieva, Dessi P; Riddell, Michael C

2017-10-01

There is no question that regular exercise can be beneficial and lead to improvements in overall cardiovascular health. However, for patients with diabetes, exercise can also lead to challenges in maintaining blood glucose balance, particularly if patients are prescribed insulin or certain oral hypoglycemic agents. Hypoglycemia is the most common adverse event associated with exercise and insulin therapy, and the fear of hypoglycemia is also the greatest barrier to exercise for many patients. With the appropriate insulin dose adjustments and, in some cases, carbohydrate supplementation, blood glucose levels can be better managed during exercise and in recovery. In general, insulin strategies that help facilitate weight loss with regular exercise and recommendations around exercise adjustments to prevent hypoglycemia and hyperglycemia are often not discussed with patients because the recommendations can be complex and may differ from one individual to the next. This is a review of the current published literature on insulin dose adjustments and starting-point strategies for patients with diabetes in preparation for safe exercise. Copyright © 2017 Diabetes Canada. Published by Elsevier Inc. All rights reserved.

[Physical activity and exercise training in the prevention and therapy of type 2 diabetes mellitus].

PubMed

Francesconi, Claudia; Lackinger, Christian; Weitgasser, Raimund; Haber, Paul; Niebauer, Josef

2016-04-01

Lifestyle in general (nutrition, exercise, smoking habits), besides the genetic predisposition, is known to be a strong predictor for the development of diabetes. Exercise in particular is not only useful in improving glycaemia by lowering insulin resistance and positively affect insulin secretion, but to reduce cardiovascular risk.To gain substantial health benefits a minimum of 150 min of moderate or vigorous intense aerobic physical activity and muscle strengthening activities per week are needed. The positive effect of training correlates directly with the amount of fitness gained and lasts only as long as the fitness level is sustained. The effect of exercise is independent of age and gender. It is reversible and reproducible.Based on the large evidence of exercise referral and prescription the Austrian Diabetes Associations aims to implement the position of a "physical activity adviser" in multi-professional diabetes care.

[Obesity and cardiometabolic risk factors during pregnancy].

PubMed

Callegari, Sandra Beatriz Mangucci; de Resende, Elisabete Aparecida Mantovani Rodrigues; Barbosa Neto, Octávio; Rodrigues, Virmondes; de Oliveira, Eduardo Mangucci; Borges, Maria de Fátima

2014-10-01

To assess cardiometabolic risk factors during normal pregnancy and the influence of maternal obesity on them. This study included 25 healthy pregnant women with a single pregnancy and a gestational age of less than twenty weeks. Longitudinal analysis of blood pressure, body weight, body mass index (BMI), serum concentrations of leptin, adiponectin, cortisol, total cholesterol and fractions, triglycerides, uric acid, fasting glucose, oral glucose tolerance test, HOMA-IR and insulin/glucose ratio was performed each trimester during pregnancy. In order to evaluate the impact of obesity, pregnant women were divided into two groups based on BMI for the first quarter of pregnancy: Gpn for pregnant women with BMI<25 kg/m2 and Gso for BMI≥25 kg/m2. One-Way ANOVA for repeated measurements or Friedman test and Student-t or Mann-Whitney tests for statistical comparisons and Pearson correlations test were used for statistical analysis. The mean values for the first quarter of pregnancy for the following parameters were: age: 22 years; weight: 66.3 kg and BMI 26.4 kg/m2, with 20.2 and 30.7 kg/m2 for the Gpn and Gso groups, respectively. Mean weight gain during pregnancy was ±12.7 kg with 10.3 kg for the Gso group and 15.2 kg for the Gpn group. Regarding plasma determinations, cortisol, uric acid and lipid profile increased during all trimesters of pregnancy, except for HDL-cholesterol, which did not change. Blood pressure, insulin and HOMA-IR only increased in the third quarter of pregnancy. The Gso group tended to gain more weight and to show higher concentrations of leptin, total cholesterol, LDL-cholesterol, VLDL-cholesterol, TG, glucose, insulin, HOMA-IR, besides lower HDL-cholesterol and greater diastolic blood pressure in the 3rd quarter of pregnancy. Three pregnant women developed gestational hypertension, presented prepregnancy obesity, excessive weight gain, hyperleptinemia and an insulin/glucose ratio greater than two. Weight and BMI were positively correlated with total cholesterol and its LDL fraction, TG, uric acid, fasting blood glucose, insulin and HOMA-IR; and were negatively correlated with adiponectin and HDL-cholesterol. Leptin level was positively correlated with blood pressure. The metabolic changes in pregnancy are more significant in obese women, suggesting, as expected, an increased risk of cardiometabolic complications. During their first visit for prenatal care, obese women should be informed about these risks, have their BMI and insulin/glucose ratio calculated along with their lipid profile to identify pregnant women at higher risk for cardiovascular diseases.

[Obesity and cardiometabolic risk factors during pregnancy.

PubMed

Callegari, Sandra Beatriz Mangucci; Resende, Elisabete Aparecida Mantovani Rodrigues de; Barbosa Neto, Octávio; Rodrigues Junior, Virmondes; Oliveira, Eduardo Mangucci de; Borges, Maria de Fátima

2014-10-03

To assess cardiometabolic risk factors during normal pregnancy and the influence of maternal obesity on them. This study included 25 healthy pregnant women with a single pregnancy and a gestational age of less than twenty weeks. Longitudinal analysis of blood pressure, body weight, body mass index (BMI), serum concentrations of leptin, adiponectin, cortisol, total cholesterol and fractions, triglycerides, uric acid, fasting glucose, oral glucose tolerance test, HOMA-IR and insulin/glucose ratio was performed each trimester during pregnancy. In order to evaluate the impact of obesity, pregnant women were divided into two groups based on BMI for the first quarter of pregnancy: Gpn for pregnant women with BMI<25 kg/m2 and Gso for BMI≥25 kg/m2. One-Way ANOVA for repeated measurements or Friedman test and Student-t or Mann-Whitney tests for statistical comparisons and Pearson correlations test were used for statistical analysis. The mean values for the first quarter of pregnancy for the following parameters were: age: 22 years; weight: 66.3 kg and BMI 26.4 kg/m2, with 20.2 and 30.7 kg/m2 for the Gpn and Gso groups, respectively. Mean weight gain during pregnancy was ±12.7 kg with 10.3 kg for the Gso group and 15.2 kg for the Gpn group. Regarding plasma determinations, cortisol, uric acid and lipid profile increased during all trimesters of pregnancy, except for HDL-cholesterol, which did not change. Blood pressure, insulin and HOMA-IR only increased in the third quarter of pregnancy. The Gso group tended to gain more weight and to show higher concentrations of leptin, total cholesterol, LDL-cholesterol, VLDL-cholesterol, TG, glucose, insulin, HOMA-IR, besides lower HDL-cholesterol and greater diastolic blood pressure in the 3rd quarter of pregnancy. Three pregnant women developed gestational hypertension, presented prepregnancy obesity, excessive weight gain, hyperleptinemia and an insulin/glucose ratio greater than two. Weight and BMI were positively correlated with total cholesterol and its LDL fraction, TG, uric acid, fasting blood glucose, insulin and HOMA-IR; and were negatively correlated with adiponectin and HDL-cholesterol. Leptin level was positively correlated with blood pressure. The metabolic changes in pregnancy are more significant in obese women, suggesting, as expected, an increased risk of cardiometabolic complications. During their first visit for prenatal care, obese women should be informed about these risks, have their BMI and insulin/glucose ratio calculated along with their lipid profile to identify pregnant women at higher risk for cardiovascular diseases.

Maternal obesity characterized by gestational diabetes increases the susceptibility of rat offspring to hepatic steatosis via a disrupted liver metabolome

PubMed Central

Pereira, Troy J; Fonseca, Mario A; Campbell, Kristyn E; Moyce, Brittany L; Cole, Laura K; Hatch, Grant M; Doucette, Christine A; Klein, Julianne; Aliani, Michel; Dolinsky, Vernon W

2015-01-01

Maternal obesity is associated with a high risk for gestational diabetes mellitus (GDM), which is a common complication of pregnancy. The influence of maternal obesity and GDM on the metabolic health of the offspring is poorly understood. We hypothesize that GDM associated with maternal obesity will cause obesity, insulin resistance and hepatic steatosis in the offspring. Female Sprague-Dawley rats were fed a high-fat (45%) and sucrose (HFS) diet to cause maternal obesity and GDM. Lean control pregnant rats received low-fat (LF; 10%) diets. To investigate the interaction between the prenatal environment and postnatal diets, rat offspring were assigned to LF or HFS diets for 12 weeks, and insulin sensitivity and hepatic steatosis were evaluated. Pregnant GDM dams exhibited excessive gestational weight gain, hyperinsulinaemia and hyperglycaemia. Offspring of GDM dams gained more weight than the offspring of lean dams due to excess adiposity. The offspring of GDM dams also developed hepatic steatosis and insulin resistance. The postnatal consumption of a LF diet did not protect offspring of GDM dams against these metabolic disorders. Analysis of the hepatic metabolome revealed increased diacylglycerol and reduced phosphatidylethanolamine in the offspring of GDM dams compared to offspring of lean dams. Consistent with altered lipid metabolism, the expression of CTP:phosphoethanolamine cytidylyltransferase, and peroxisomal proliferator activated receptor-α mRNA was reduced in the livers of GDM offspring. GDM exposure programs gene expression and hepatic metabolite levels and drives the development of hepatic steatosis and insulin resistance in young adult rat offspring. Key points Gestational diabetes mellitus is a common complication of pregnancy, but its effects on the offspring are poorly understood. We developed a rat model of diet-induced gestational diabetes mellitus that recapitulates many of the clinical features of the disease, including excessive gestational weight gain, glucose intolerance, hyperinsulinaemia and mild hyperglycaemia. Compared to the offspring of lean dams, exposure to gestational diabetes mellitus during the prenatal period resulted in obesity, hepatic steatosis and insulin resistance in young rat offspring that consumed a postnatal diet that was low in fat. The combination of maternal gestational diabetes mellitus and the postnatal consumption of a high-fat diet by the offspring caused a more severe metabolic phenotype. Metabolomic profiling of the liver tissues of the offspring of gestational diabetic dams revealed accumulation of lipotoxic lipids and reduced phosphatidylethanolamine levels compared to the offspring of lean dams. The results establish that gestational diabetes mellitus is a driver of hepatic steatosis and insulin resistance in the offspring. PMID:25922055

Chromium (D-phenylalanine)3 supplementation alters glucose disposal, insulin signaling, and glucose transporter-4 membrane translocation in insulin-resistant mice.

PubMed

Dong, Feng; Kandadi, Machender Reddy; Ren, Jun; Sreejayan, Nair

2008-10-01

Chromium has gained popularity as a nutritional supplement for diabetic and insulin-resistant subjects. This study was designed to evaluate the effect of chronic administration of a novel chromium complex of d-phenylalanine [Cr(D-phe)(3)] in insulin-resistant, sucrose-fed mice. Whole-body insulin resistance was generated in FVB mice by 9 wk of sucrose feeding, following which they were randomly assigned to be unsupplemented (S group) or to receive oral Cr(D-phe)(3) in drinking water (SCr group) at a dose of 45 mug.kg(-1).d(-1) ( approximately 3.8 mug of elemental chromium.kg(-1).d(-1)). A control group (C) did not consume sucrose and was not supplemented. Sucrose-fed mice had an elevated serum insulin concentration compared with controls and this was significantly lower in sucrose-fed mice that received Cr(D-phe)(3), which did not differ from controls. Impaired glucose tolerance in sucrose-fed mice, evidenced by the poor glucose disposal rate following an intraperitoneal glucose tolerance test, was significantly improved in mice receiving Cr(D-phe)(3). Chromium supplementation significantly enhanced insulin-stimulated Akt phosphorylation and membrane-associated glucose transporter-4 in skeletal muscles of sucrose-fed mice. In cultured adipocytes rendered insulin resistant by chronic exposure to high concentrations of glucose and insulin, Cr(D-phe)(3) augmented Akt phosphorylation and glucose uptake. These results indicate that dietary supplementation with Cr(D-phe)(3) may have potential beneficial effects in insulin-resistant, prediabetic conditions.

Hypopituitarism

MedlinePlus

... hormone (ACTH) -- stimulates the adrenal gland to release cortisol; cortisol helps to maintain blood pressure and blood sugar ... may include: Brain CT scan Pituitary MRI ACTH Cortisol Estradiol (estrogen) Follicle-stimulating hormone (FSH) Insulin-like ...

Metabolomic Response of Skeletal Muscle to Aerobic Exercise Training in Insulin Resistant Type 1 Diabetic Rats.

PubMed

Dotzert, Michelle S; Murray, Michael R; McDonald, Matthew W; Olver, T Dylan; Velenosi, Thomas J; Hennop, Anzel; Noble, Earl G; Urquhart, Brad L; Melling, C W James

2016-05-20

The etiology of insulin resistance in Type 1 Diabetes (T1D) is unknown, however it affects approximately 20% of T1D patients. Intramyocellular lipids (IMCL) have been identified as a mechanism of insulin resistance. We examined skeletal muscle of T1D rats to determine if alterations in lipid metabolism were evident and whether aerobic exercise training improves IMCL and insulin resistance. To do so, 48 male Sprague-Dawley rats were divided into control (C), sedentary diabetes (D) and diabetes exercise (DX) groups. Following multiple low-dose Streptozotocin (STZ) injections (20 mg/kg), glycemia (9-15 mM) was maintained using insulin treatment. DX were treadmill trained at high intensity (~75% V02max; 5days/week) for 10 weeks. The results demonstrate that D exhibited insulin resistance compared with C and DX, indicated by decreased glucose infusion rate during a hyperinsulinemic-euglycemic clamp (p < 0.05). There were no differences between C and DX, suggesting that exercise improved insulin resistance (p < 0.05). Metabolomics analysis revealed a significant shift in lipid metabolism whereby notable fatty acid metabolites (arachidonic acid, palmitic acid and several polyunsaturated fatty acids) were significantly elevated in D compared to C and DX. Based on the intermediates observed, insulin resistance in T1D is characterized by an insulin-desensitizing intramyocellular fatty acid metabolite profile that is ameliorated with exercise training.

Insulin treatment promotes tyrosine phosphorylation of PKR and inhibits polyIC induced PKR threonine phosphorylation.

PubMed

Swetha, Medchalmi; Ramaiah, Kolluru V A

2015-11-01

Tyrosine phosphorylation of insulin receptor beta (IRβ) in insulin treated HepG2 cells is inversely correlated to ser(51) phosphorylation in the alpha-subunit of eukaryotic initiation factor 2 (eIF2α) that regulates protein synthesis. Insulin stimulates interaction between IRβ and PKR, double stranded RNA-dependent protein kinase, also known as EIF2AK2, and phosphorylation of tyrosine residues in PKR, as analyzed by immunoprecipitation and pull down assays using anti-IRβ and anti-phosphotyrosine antibodies, recombinant IRβ and immunopurified PKR. Further polyIC or synthetic double stranded RNA-induced threonine phosphorylation or activation of immunopurified and cellular PKR is suppressed in the presence of insulin treated purified IRβ and cell extracts. Acute, but not chronic, insulin treatment enhances tyrosine phosphorylation of IRβ, its interaction with PKR and tyrosine phosphorylation of PKR. In contrast, lipopolysaccharide that stimulates threonine phosphorylation of PKR and eIF2α phosphorylation and AG 1024, an inhibitor of the tyrosine kinase activity of IRβ, reduces PKR association with the receptor, IRβ in HepG2 cells. These findings therefore may suggest that tyrosine phosphorylated PKR plays a role in the regulation of insulin induced protein synthesis and in maintaining insulin sensitivity, whereas, suppression of polyIC-mediated threonine phosphorylation of PKR by insulin compromises its ability to fight against virus infection in host cells. Copyright © 2015 Elsevier Inc. All rights reserved.

Efficacy and Safety of Insulin Glargine 300 U/mL versus 100 U/mL in Diabetes Mellitus: A Comprehensive Review of the Literature

PubMed Central

2018-01-01

To achieve good metabolic control in diabetes and maintain it in the long term, a combination of changes in lifestyle and pharmacological treatment is necessary. The need for insulin depends upon the balance between insulin secretion and insulin resistance. Insulin is considered the most effective glucose-lowering therapy available and is required by people with type 1 diabetes mellitus to control their blood glucose levels; yet, many people with type 2 diabetes mellitus will also eventually require insulin therapy, due to the progressive nature of the disease. A variety of long-acting insulins is currently used for basal insulin therapy (such as insulin glargine, degludec, and detemir), each having sufficient pharmacodynamic and pharmacokinetic profiles to afford lower intrapatient variability and an extended duration of action. The new glargine-300 formulation was developed to have a flatter and more extended time-action profile than the original glargine-100, and these characteristics may translate into more stable and sustained glycemic control over a 24 h dosing interval. The objective of this comprehensive review was to summarize the available evidence on the clinical efficacy and safety of glargine-300 versus glargine-100 from the EDITION clinical trial program, in patients with type 1 and type 2 diabetes mellitus. PMID:29619381

Dose accuracy of a reusable insulin pen using a cartridge system with an integrated plunger mechanism.

PubMed

Clarke, Alastair; Dain, Marie-Paule

2006-09-01

Pen injection devices are a common method of administering insulin for patients with diabetes. Pen devices must comply with guidelines prepared by the International Organization for Standardization, which include device dose accuracy and precision. OptiClik (sanofi-aventis) was developed to fulfil unmet needs of patients with diabetes, including: easier cartridge changing, clearer dose display and readability, and a larger dose of insulin to be delivered with a single injection. In this paper, the authors report on the dose accuracy of the OptiClik pen device, which uses a novel cartridge system with an integrated plunger for easier cartridge changing. The authors show that OptiClik accurately delivers a required dose of insulin, which is maintained over the lifetime of the pen. OptiClik offers a significant contribution to the treatment of diabetes.

Is the current standard of care leading to cost-effective outcomes for patients with type 2 diabetes requiring insulin? A long-term health economic analysis for the UK.

PubMed

Valentine, W J; Curtis, B H; Pollock, R F; Van Brunt, K; Paczkowski, R; Brändle, M; Boye, K S; Kendall, D M

2015-07-01

The aim of the analysis was to investigate whether insulin intensification, based on the use of intensive insulin regimens as recommended by the current standard of care in routine clinical practice, would be cost-effective for patients with type 2 diabetes in the UK. Clinical data were derived from a retrospective analysis of 3185 patients with type 2 diabetes on basal insulin in The Health Improvement Network (THIN) general practice database. In total, 48% (614 patients) intensified insulin therapy, defined by adding bolus or premix insulin to a basal regimen, which was associated with a reduction in HbA1c and an increase in body mass index. Projections of clinical outcomes and costs (2011 GBP) over patients' lifetimes were made using a recently validated type 2 diabetes model. Immediate insulin intensification was associated with improvements in life expectancy, quality-adjusted life expectancy and time to onset of complications versus no intensification or delaying intensification by 2, 4, 6, or 8 years. Direct costs were higher with the insulin intensification strategy (due to the acquisition costs of insulin). Incremental cost-effectiveness ratios for insulin intensification were GBP 32,560, GBP 35,187, GBP 40,006, GBP 48,187 and GBP 55,431 per QALY gained versus delaying intensification 2, 4, 6 and 8 years, and no intensification, respectively. Although associated with improved clinical outcomes, insulin intensification as practiced in the UK has a relatively high cost per QALY and may not lead to cost-effective outcomes for patients with type 2 diabetes as currently defined by UK cost-effectiveness thresholds. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Insulin sensitizers prevent fine particulate matter-induced vascular insulin resistance and changes in endothelial progenitor cell homeostasis

PubMed Central

McCracken, James P.; Bhatnagar, Aruni; Conklin, Daniel J.

2016-01-01

Exposure to fine particular matter (PM2.5) increases the risk of developing cardiovascular disease and Type 2 diabetes. Because blood vessels are sensitive targets of air pollutant exposure, we examined the effects of concentrated ambient PM2.5 (CAP) on vascular insulin sensitivity and circulating levels of endothelial progenitor cells (EPCs), which reflect cardiovascular health. We found that CAP exposure for 9 days decreased insulin-stimulated Akt phosphorylation in the aorta of mice maintained on control diet. This change was accompanied by the induction of IL-1β and increases in the abundance of cleaved IL-18 and p10 subunit of Casp-1, consistent with the activation of the inflammasome pathway. CAP exposure also suppressed circulating levels of EPCs (Flk-1+/Sca-1+ cells), while enhancing the bone marrow abundance of these cells. Although similar changes in vascular insulin signaling and EPC levels were observed in mice fed high-fat diet, CAP exposure did not exacerbate diet-induced changes in vascular insulin resistance or EPC homeostasis. Treatment with an insulin sensitizer, metformin or rosiglitazone, prevented CAP-induced vascular insulin resistance and NF-κB and inflammasome activation and restored peripheral blood and bone marrow EPC levels. These findings suggest that PM2.5 exposure induces diet-independent vascular insulin resistance and inflammation and prevents EPC mobilization, and that this EPC mobilization defect could be mediated by vascular insulin resistance. Impaired vascular insulin sensitivity may be an important mechanism underlying PM2.5-induced vascular injury, and pharmacological sensitization to insulin action could potentially prevent deficits in vascular repair and mitigate vascular inflammation due to exposure to elevated levels of ambient air pollution. Listen to this article's corresponding podcast at http://ajpheart.podbean.com/e/particulate-matter-induced-vascular-insulin-resistance/. PMID:27016579

New technologies in the treatment of type 1 diabetes.

PubMed

Schmidt, Signe

2013-11-01

Type 1 diabetes is a chronic condition characterized by insufficient production of insulin, a hormone needed for proper control of blood glucose levels. People with type 1 diabetes must monitor their blood glucose throughout the day using a glucose meter or a continuous glucose monitor, calculate how much insulin is needed to maintain normal blood glucose levels, and administer the insulin dose by pen injection or insulin pump infusion into the subcutaneous tissue. In recent years, several new technologies for the treatment of type 1 diabetes have been developed. This PhD thesis covers two studies of the effects of commercially available technologies--sensor-augmented pump therapy and automated insulin bolus calculators--when used in clinical practice. Both studies demonstrated that these technologies have the potential to improve diabetes care. In addition, two in-clinic studies related to emerging technologies--closed-loop glucose control and virtual simulation environments--are included in the thesis. The results of these experiments provided proof of concept and will serve as a basis for further research in these fields.

Reproducible insulin secretion from isolated rat pancreas preparations using an organ bath.

PubMed

Morita, Asuka; Ouchi, Motoshi; Terada, Misao; Kon, Hiroe; Kishimoto, Satoko; Satoh, Keitaro; Otani, Naoyuki; Hayashi, Keitaro; Fujita, Tomoe; Inoue, Ken-Ichi; Anzai, Naohiko

2018-02-09

Diabetes mellitus is a lifestyle-related disease that is characterized by inappropriate or diminished insulin secretion. Ex vivo pharmacological studies of hypoglycemic agents are often conducted using perfused pancreatic preparations. Pancreas preparations for organ bath experiments do not require cannulation and are therefore less complex than isolated perfused pancreas preparations. However, previous research has generated almost no data on insulin secretion from pancreas preparations using organ bath preparations. The purpose of this study was to investigate the applicability of isolated rat pancreas preparations using the organ bath technique in the quantitative analysis of insulin secretion from β-cells. We found that insulin secretion significantly declined during incubation in the organ bath, whereas it was maintained in the presence of 1 µM GLP-1. Conversely, amylase secretion exhibited a modest increase during incubation and was not altered in the presence of GLP-1. These results demonstrate that the pancreatic organ bath preparation is a sensitive and reproducible method for the ex vivo assessment of the pharmacological properties of hypoglycemic agents.

Can natural polymers assist in delivering insulin orally?

PubMed

Nur, Mokhamad; Vasiljevic, Todor

2017-10-01

Diabetes mellitus is one of the most grave and lethal non communicable diseases. Insulin is normally used to medicate diabetes. Due to bioavailability issues, the most regular route of administration is through injection, which may pose compliance problems to treatment. The oral administration thus appears as a suitable alternative, but with several important problems. Low stability of insulin in the gastrointestinal tract and low intestinal permeation are some of the issues. Encapsulation of insulin into polymer-based particles emerges as a plausible strategy. Different encapsulation approaches and polymers have been used in this regard. Polymers with different characteristics from natural or synthetic origin have been assessed to attain this goal, with natural polymers being preferable. Natural polymers studied so far include chitosan, alginate, carrageenan, starch, pectin, casein, tragacanth, dextran, carrageenan, gelatine and cyclodextrin. While some promising knowledge and results have been gained, a polymeric-based particle system to deliver insulin orally has not been introduced onto the market yet. In this review, effectiveness of different natural polymer materials developed so far along with fabrication techniques are evaluated. Copyright © 2017 Elsevier B.V. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Rui; Su, Rongxin, E-mail: surx@tju.edu.cn; Tianjin Key Laboratory of Membrane Science and Desalination Technology, Tianjin University, Tianjin 300072

Highlights: {yields} We compare the structures of insulin upon heating with or without laser irradiation. {yields} Laser irradiation inhibits insulin fibrillation and may be of insert for mechanistic disease studies. {yields} Online laser measurements should be carefully used in the study of amyloid proteins. -- Abstract: Protein aggregation and amyloid fibrillation can lead to several serious diseases and protein drugs ineffectiveness; thus, the detection and inhibition of these processes have been of great interest. In the present study, the inhibition of insulin amyloid fibrillation by laser irradiation was investigated using dynamic light scattering (DLS), transmission electron microscopy (TEM), far-UV circularmore » dichroism (far-UV CD), and thioflavin T (ThT) fluorescence. During heat-induced aggregation, the size distribution of two insulin solutions obtained by online and offline dynamic light scattering were different. The laser-on insulin in the presence of 0.1 M NaCl exhibited fewer fibrils than the laser-off insulin, whereas no insulin fibril under laser irradiation was observed in the absence of 0.1 M NaCl for 45 h incubation. Moreover, our CD results showed that the laser-irradiated insulin solution maintained mainly an {alpha}-helical conformation, but the laser-off insulin solution formed bulk fibrils followed by a significant increase in {beta}-sheet content for 106 h incubation. These findings provide an inhibition method for insulin amyloid fibrillation using the laser irradiation and demonstrate that the online long-time laser measurements should be carefully used in the study of amyloid proteins because they may change the original results.« less

Detemir insulin for the treatment of diabetes mellitus in dogs.

PubMed

Fracassi, Federico; Corradini, Sara; Hafner, Michaela; Boretti, Felicitas S; Sieber-Ruckstuhl, Nadia S; Reusch, Claudia E

2015-07-01

To investigate the effects of insulin detemir in dogs with diabetes mellitus. Prospective, uncontrolled clinical trial. 10 client-owned dogs with naturally occurring diabetes mellitus. Dogs were treated with insulin detemir SC every 12 hours for 6 months. Follow-up evaluations were done at 1, 2, 4, 12, and 24 weeks and included evaluation of clinical signs and measurement of blood glucose concentration curves and serum fructosamine concentrations. Insulin detemir administration resulted in a significant decrease in blood glucose and serum fructosamine concentrations at 6 months, compared with pretreatment values. Median insulin dosage at the end of the study was 0.12 U/kg (0.055 U/lb; range, 0.05 to 0.34 U/kg [0.023 to 0.155 U/lb], SC, q 12 h). Hypoglycemia was identified in 22% (10/45) of the blood glucose concentration curves, and 6 episodes of clinical hypoglycemia in 4 dogs were recorded. A subjective improvement in clinical signs was observed in all dogs during the 6-month study period. On the basis of clinical signs and blood glucose concentration curves, efficacy of insulin detemir at the end of the study was considered good in 5 dogs, moderate in 3, and poor in 2. Results suggested that SC injection of insulin detemir every 12 hours may be a viable treatment for diabetes mellitus in dogs. Insulin detemir dosages were lower than reported dosages of other insulin types needed to maintain glycemic control, suggesting that insulin detemir should be used with caution, especially in small dogs.

Dietary supplementation with Agaricus blazei murill extract prevents diet-induced obesity and insulin resistance in rats.

PubMed

Vincent, Mylène; Philippe, Erwann; Everard, Amandine; Kassis, Nadim; Rouch, Claude; Denom, Jessica; Takeda, Yorihiko; Uchiyama, Shoji; Delzenne, Nathalie M; Cani, Patrice D; Migrenne, Stéphanie; Magnan, Christophe

2013-03-01

Dietary supplement may potentially help to fight obesity and other metabolic disorders such as insulin-resistance and low-grade inflammation. The present study aimed to test whether supplementation with Agaricus blazei murill (ABM) extract could have an effect on diet-induced obesity in rats. Wistar rats were fed with control diet (CD) or high-fat diet (HF) and either with or without supplemented ABM for 20 weeks. HF diet-induced body weight gain and increased fat mass compared to CD. In addition HF-fed rats developed hyperleptinemia and insulinemia as well as insulin resistance and glucose intolerance. In HF-fed rats, visceral adipose tissue also expressed biomarkers of inflammation. ABM supplementation in HF rats had a protective effect against body weight gain and all study related disorders. This was not due to decreased food intake which remained significantly higher in HF rats whether supplemented with ABM or not compared to control. There was also no change in gut microbiota composition in HF supplemented with ABM. Interestingly, ABM supplementation induced an increase in both energy expenditure and locomotor activity which could partially explain its protective effect against diet-induced obesity. In addition a decrease in pancreatic lipase activity is also observed in jejunum of ABM-treated rats suggesting a decrease in lipid absorption. Taken together these data highlight a role for ABM to prevent body weight gain and related disorders in peripheral targets independently of effect in food intake in central nervous system. Copyright © 2012 The Obesity Society.

77 FR 59625 - NIH Evidence-Based Methodology Workshop on Polycystic Ovary; Syndrome

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-28

... periods (for women of reproductive age) Acne Weight gain Excess hair growth on the face and body Thinning scalp hair Ovarian cysts. Women with PCOS are often resistant to the biological effects of insulin and...

The Intrauterine Growth Restriction Phenotype: Fetal Adaptations and Potential Implications for Later Life Insulin Resistance and Diabetes

PubMed Central

Thorn, Stephanie R.; Rozance, Paul J.; Brown, Laura D.; Hay, William W.

2011-01-01

The intrauterine growth restricted (IUGR) fetus develops unique metabolic adaptations in response to exposure to reduced nutrient supply. These adaptations provide survival value for the fetus by enhancing the capacity of the fetus to take up and use nutrients, thereby reducing the need for nutrient supply. Each organ and tissue in the fetus adapts differently, with the brain showing the greatest capacity for maintaining nutrient supply and growth. Such adaptations, if persistent, also have the potential in later life to promote nutrient uptake and storage, which directly lead to complications of obesity, insulin resistance, reduced insulin production, and type 2 diabetes. PMID:21710398

Metabolic responses with endothelin antagonism in a model of insulin resistance.

PubMed

Berthiaume, Nathalie; Wessale, Jerry L; Opgenorth, Terry J; Zinker, Bradley A

2005-06-01

Atrasentan, an endothelin antagonist, would have beneficial effects on metabolic responses in a model of insulin resistance. Zucker lean or fatty rats were maintained either on regular (lean and fatty control, n = 12) or atrasentan-treated water (5 mg/kg/d, fatty atrasentan, n = 13) for 6 weeks. There was no significant difference in water intake and body weight with the atrasentan-treated group compared with fatty controls. Although atrasentan had no effect on 3-hour fasting glucose levels, it reduced fasting insulin levels between weeks 2 and 4 of treatment by 53% (fatty control vs fatty atrasentan, P < .01). Atrasentan decreased the incremental area under the plasma glucose response curve ( Delta AUC) after a nutritionally complete meal tolerance test (MTT), by 28% in the atrasentan-treated group compared with fatty controls ( P < .05), and decreased the MTT-induced insulin Delta AUC by 63% in treated animals compared with the fatty control group ( P < .01). In addition, atrasentan significantly decreased the MTT-induced glucose-insulin index Delta AUC by 58% in treated rats compared with fatty controls ( P < .01). In summary, in the Zucker fatty rat, atrasentan significantly reduces (1) 3-hour fasting insulin levels at 4 weeks, (2) glucose and insulin MTT-induced Delta AUCs, and (3) the MTT-induced glucose-insulin index Delta AUC. These results demonstrate an improvement in hyperinsulinemia as well as in glucose tolerance and insulin sensitivity with chronic endothelin antagonism in a model of insulin resistance and suggest that chronic endothelin antagonism may have benefits in the treatment of insulin resistance and/or diabetes.

PKB/Akt phosphorylation of ERRγ contributes to insulin-mediated inhibition of hepatic gluconeogenesis.

PubMed

Kim, Don-Kyu; Kim, Yong-Hoon; Hynx, Debby; Wang, Yanning; Yang, Keum-Jin; Ryu, Dongryeol; Kim, Kyung Seok; Yoo, Eun-Kyung; Kim, Jeong-Sun; Koo, Seung-Hoi; Lee, In-Kyu; Chae, Ho-Zoon; Park, Jongsun; Lee, Chul-Ho; Biddinger, Sudha B; Hemmings, Brian A; Choi, Hueng-Sik

2014-12-01

Insulin resistance, a major contributor to the pathogenesis of type 2 diabetes, leads to increased hepatic glucose production (HGP) owing to an impaired ability of insulin to suppress hepatic gluconeogenesis. Nuclear receptor oestrogen-related receptor γ (ERRγ) is a major transcriptional regulator of hepatic gluconeogenesis. In this study, we investigated insulin-dependent post-translational modifications (PTMs) altering the transcriptional activity of ERRγ for the regulation of hepatic gluconeogenesis. We examined insulin-dependent phosphorylation and subcellular localisation of ERRγ in cultured cells and in the liver of C57/BL6, leptin receptor-deficient (db/db), liver-specific insulin receptor knockout (LIRKO) and protein kinase B (PKB) β-deficient (Pkbβ (-/-)) mice. To demonstrate the role of ERRγ in the inhibitory action of insulin on hepatic gluconeogenesis, we carried out an insulin tolerance test in C57/BL6 mice expressing wild-type or phosphorylation-deficient mutant ERRγ. We demonstrated that insulin suppressed the transcriptional activity of ERRγ by promoting PKB/Akt-mediated phosphorylation of ERRγ at S179 and by eliciting translocation of ERRγ from the nucleus to the cytoplasm through interaction with 14-3-3, impairing its ability to promote hepatic gluconeogenesis. In addition, db/db, LIRKO and Pkbβ (-/-) mice displayed enhanced ERRγ transcriptional activity due to a block in PKBβ-mediated ERRγ phosphorylation during refeeding. Finally, the phosphorylation-deficient mutant ERRγ S179A was resistant to the inhibitory action of insulin on HGP. These results suggest that ERRγ is a major contributor to insulin action in maintaining hepatic glucose homeostasis.

Whey Protein Reduces Early Life Weight Gain in Mice Fed a High-Fat Diet

PubMed Central

Tranberg, Britt; Hellgren, Lars I.; Lykkesfeldt, Jens; Sejrsen, Kristen; Jeamet, Aymeric; Rune, Ida; Ellekilde, Merete; Nielsen, Dennis S.; Hansen, Axel Kornerup

2013-01-01

An increasing number of studies indicate that dairy products, including whey protein, alleviate several disorders of the metabolic syndrome. Here, we investigated the effects of whey protein isolate (whey) in mice fed a high-fat diet hypothesising that the metabolic effects of whey would be associated with changes in the gut microbiota composition. Five-week-old male C57BL/6 mice were fed a high-fat diet ad libitum for 14 weeks with the protein source being either whey or casein. Faeces were collected at week 0, 7, and 13 and the fecal microbiota was analysed by denaturing gradient gel electrophoresis analyses of PCR-derived 16S rRNA gene (V3-region) amplicons. At the end of the study, plasma samples were collected and assayed for glucose, insulin and lipids. Whey significantly reduced body weight gain during the first four weeks of the study compared with casein (P<0.001–0.05). Hereafter weight gain was similar resulting in a 15% lower final body weight in the whey group relative to casein (34.0±1.0 g vs. 40.2±1.3 g, P<0.001). Food intake was unaffected by protein source throughout the study period. Fasting insulin was lower in the whey group (P<0.01) and glucose clearance was improved after an oral glucose challenge (P<0.05). Plasma cholesterol was lowered by whey compared to casein (P<0.001). The composition of the fecal microbiota differed between high- and low-fat groups at 13 weeks (P<0.05) whereas no difference was seen between whey and casein. In conclusion, whey initially reduced weight gain in young C57BL/6 mice fed a high-fat diet compared to casein. Although the effect on weight gain ceased, whey alleviated glucose intolerance, improved insulin sensitivity and reduced plasma cholesterol. These findings could not be explained by changes in food intake or gut microbiota composition. Further studies are needed to clarify the mechanisms behind the metabolic effects of whey. PMID:23940754

[D-Leu-4]-OB3, a synthetic peptide amide with leptin-like activity, augments the effects of orally delivered exenatide and pramlintide acetate on energy balance and glycemic control in insulin-resistant male C57BLK/6-m db/db mice.

PubMed

Leinung, Matthew C; Grasso, Patricia

2012-11-10

The escalation predicted for the incidence of both type 2 diabetes mellitus and obesity has prompted investigators to search for additional pharmacotherapeutic approaches to their treatment. Two of these approaches, combination pharmacotherapy and utilization of leptin-related bioactive synthetic peptides as anti-diabetes/anti-obesity agents, were used in the present study. Exenatide or pramlintide acetate was reconstituted in dodecyl maltoside (DDM) in the absence or presence of [D-Leu-4]-OB3, and delivered orally by gavage to insulin-resistant male C57BLK/6-m db/db mice twice daily for 14 days. Body weight gain, food and water intake, blood glucose, and serum insulin levels were measured. Mice given DDM alone for 14 days were 19.7% heavier than they were at the beginning of the study, while oral delivery of exenatide or [D-Leu-4]-OB3 in DDM reduced body weight gain to only 13.9% and 11.5%, respectively, of initial body weight. Mice receiving exenatide and [D-Leu-4]-OB3 were 4.2% lighter than they were at the beginning of the study. In another study, Intravail® treated control mice gained 38.2% of their initial body weight, while mice receiving pramlintide acetate or [D-Leu-4]-OB3 were only 26.8% and 25.4% heavier, respectively, at the end of the study, Co-administration of pramlintide acetate and [D-Leu-4]-OB3 did not further enhance the effect of pramlintide acetate on body weight gain. Food intake was reduced by exenatide, pramlintide acetate, and [D-Leu-4]-OB3 alone, and co-delivery with [D-Leu-4]-OB3 did not induce a further decrease. Water intake was not affected by exenatide, pramlintide acetate, or [D-Leu-4]-OB3 alone, but co-delivery of exenatide or pramlintide acetate with [D-Leu-4]-OB3 resulted in a significant reduction in water intake. Oral delivery of exenatide or pramlintide acetate in DDM significantly lowered blood glucose levels by 20.4% and 30.2%, respectively. Co-delivery with [D-Leu-4]-OB3 further reduced blood glucose by 38.3% and 50.5%, respectively. A concentration-dependent increase in serum insulin was observed in response to increasing concentrations of exenatide, and [D-Leu-4]-OB3 slightly reduced the insulin response to exenatide at all concentrations tested. Increasing concentrations of pramlintide acetate alone did not elevate serum insulin, and when given in combination with [D-Leu-4]-OB3, serum insulin levels fell below those of DDM-treated control mice. Our data indicate that (1) exenatide and pramlintide acetate, currently administered by subcutaneous injection, can be given orally in DDM; (2) the bioactivity of exenatide and pramlintide acetate is retained following oral delivery in DDM; and (3) the effects of exenatide and pramlintide acetate on energy balance and glycemic control can be enhanced by co-administration with [D-Leu-4]-OB3, a synthetic peptide amide with leptin-like activity. Copyright © 2012 Elsevier B.V. All rights reserved.

Cost-effectiveness of once daily GLP-1 receptor agonist lixisenatide compared to bolus insulin both in combination with basal insulin for the treatment of patients with type 2 diabetes in Norway.

PubMed

Huetson, Pernilla; Palmer, James L; Levorsen, Andrée; Fournier, Marie; Germe, Maeva; McLeod, Euan

2015-01-01

Lixisenatide is a potent, selective and short-acting once daily prandial glucagon-like peptide-1 receptor agonist which lowers glycohemoglobin and body weight by clinically significant amounts in patients with type 2 diabetes treated with basal insulin, with limited risk of hypoglycemia. To assess the cost-effectiveness of lixisenatide versus bolus insulin, both in combination with basal insulin, in patients with type 2 diabetes in Norway. The IMS CORE Diabetes Model, a non-product-specific and validated simulation model, was used to make clinical and cost projections. Transition probabilities, risk adjustments and the progression of complication risk factors were derived from the UK Prospective Diabetes Study, supplemented with Norwegian data. Patients were assumed to receive combination treatment with basal insulin, lixisenatide or bolus insulin therapy for 3 years, followed by intensification of a basal-bolus insulin regimen for their remaining lifetime. Simulated healthcare costs, taken from the public payer perspective, were derived from microcosting and diagnosis related groups, discounted at 4% per annum and reported in Norwegian krone (NOK). Productivity costs were also captured based on extractions from the Norwegian Labor and Welfare Administration. Health state utilities were derived from a systematic literature review. Sensitivity and scenario analyses were performed. Lixisenatide in combination with basal insulin was associated with increased quality-adjusted life years (QALYs) and reduced lifetime healthcare costs compared to bolus insulin in combination with basal insulin in patients with Type 2 diabetes, and can be considered dominant. The net monetary benefit of lixisenatide versus bolus insulin was NOK 39,369 per patient. Results were sensitive to discounting, the application of excess body weight associated disutility and uncertainty surrounding the changes in HbA1c. Lixisenatide may be considered an economically efficient therapy in combination with basal insulin in the Norwegian setting, due to cost savings, weight loss and associated gains in health-related quality of life.

Weight Gain and Metabolic Consequences of Risperidone in Young Children With Autism Spectrum Disorder

PubMed Central

Scahill, Lawrence; Jeon, Sangchoon; Boorin, Susan J.; McDougle, Christopher J.; Aman, Michael G.; Dziura, James; McCracken, James T.; Caprio, Sonia; Arnold, L. Eugene; Nicol, Ginger; Deng, Yanhong; Challa, Saankari A.; Vitiello, Benedetto

2016-01-01

Objective We examine weight gain and metabolic consequences of risperidone monotherapy in children with autism spectrum disorder (ASD). Method This was a 24-week, multisite, randomized trial of risperidone only versus risperidone plus parent training in 124 children (mean age 6.9 ± 2.35 years; 105 boys, 19 girls) with ASD and serious behavioral problems. We monitored height, weight, waist circumference, and adverse effects during the trial. Fasting blood samples were obtained pretreatment and at Week 16. Results In 97 patients with a mean of 22.9 ± 2.8 weeks risperidone exposure, there was a 5.4 ± 3.4 kg weight gain over 24 weeks (p < .0001); waist circumference increased from 60.7 ± 10.4 cm to 66.8 ± 11.3 cm (p <. 0001). At baseline 60.8% (59 of 97) patients were classified as having normal weight; by Week 24, only 29.4% (25 of 85) remained in that group. Growth curve analysis showed a significant change in body mass index (BMI) z-scores from pretreatment to Week 24 (p<.0001). This effect was significantly greater for patients with reported increased appetite in the first 8 weeks. From pretreatment to Week 16, there were significant increases in glucose (p=.02), hemoglobin A1c (p=.01), insulin (p <.0001), homeostatic model assessment–insulin resistance (HOMA-IR; p< .001), alanine aminotransferase (p=.01), and leptin (p < .0001). Adiponectin declined (p =.003). At baseline, 7 patients met conventional criteria for metabolic syndrome; by Week 16, 12 additional patients were so classified. Conclusion Rapid weight gain with risperidone treatment may promote the cascade of biochemical indices associated with insulin resistance and metabolic syndrome. Appetite, weight, waist circumference, liver function tests, blood lipids, and glucose warrant monitoring. Clinical trial registration information Drug and Behavioral Therapy for Children With Pervasive Developmental Disorders; http://clinicaltrials.gov/; NCT00080145 PMID:27126856

Insulin in UW solution exacerbates hepatic ischemia / reperfusion injury by energy depletion through the IRS-2 / SREBP-1c pathway.

PubMed

Li, Xian Liang; Man, Kwan; Ng, Kevin T; Lee, Terence K; Lo, Chung Mau; Fan, Sheung Tat

2004-09-01

Ischemia / reperfusion (I / R) injury is related to tissue graft energy status. Insulin, which is currently used in the University of Wisconsin (UW) preservation solution with insulin (UWI), is an anabolic hormone and was shown to exacerbate the hepatic I / R injury in our previous study. In this study, the energy status and regulation of metabolism genes by insulin were investigated in liver grafts preserved by UW solution. Insulin could significantly decrease adenosine triphosphate (ATP) level after 3 hours of preservation, as well as total adenine nucleotides (TANs) and energy charge (EC) levels. Energy regeneration deteriorated in the grafts preserved by insulin in terms of ATP and EC levels at 24 hours after transplantation. The insulin signal was transduced through the insulin receptor substrate-2 (IRS-2) pathway and the activity of IRS-2 was decreased gradually at the messenger ribonucleic acid (mRNA) level during cold preservation. Downstream targeting genes such as sterol regulatory element-binding protein-1c (SREBP-1c), glucokinase (GKC), and fatty acid synthase (FAS) genes, as well as phospho-glycogen synthase kinase-3beta (GSK-3beta) were activated and they showed the similar expression profiles during cold preservation. Lipoprotein metabolism was accelerated by insulin through upregulation of the activity of apolipoprotein C-III (Apo C-III) during cold preservation. The insulin-like growth factor-binding protein-1 pathway was inhibited during cold preservation. In conclusion, insulin in UW solution exacerbates hepatic I / R injury by energy depletion as the graft maintains its anabolic activity. The key enzyme activities of the energy-consuming process of glycogen and fatty acid synthesis as well as lipoprotein metabolism were accelerated by insulin through the IRS-2 / SREBP-1c pathway.

Regulation of gonadotropin receptors, gonadotropin responsiveness, and cell multiplication by somatomedin-C and insulin in cultured pig Leydig cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bernier, M.; Chatelain, P.; Mather, J.P.

1986-11-01

The author have investigated the effects of insulin and somatomedin-C/insulin like growth factor I(Sm-C) in purified porcine Leydig cells in vitro on gonadotrophins (hCG) receptor number, hCG responsiveness (cAMP and testosterone production), and thymidine incorporation into DNA. Leydig cells cultured in a serum-free medium containing transferrin, vitamin E, and insulin (5 ..mu..g/ml) maintained fairly constant both hCG receptors and hCG responsiveness. When they were cultured for 3 days in the same medium without insulin, there was a dramatic decline (more than 80%) in both hCG receptor number and hCG responsiveness. However the cAMP but not the testosterone response to forskolinmore » was normal. Both insulin and Sm-C at nanomolar concentrations prevent the decline of both hCG receptors and hCG-induced cAMP production. At nanomolar concentrations, Sm-C and insulin enhanced hCG-induced testosterone production but the effect of Sm-C was significantly higher than that of insulin. However, the effect of insulin at higher concentrations (5 ..mu..g/ml) was significantly higher than that of Sm-C at 50 ng/ml. In contrast, at nanomolar concentrations only Sm-C stimulated (/sup 3/H)-thymidine incorporation into DNA and cell multiplication, the stimulatory effect of insulin on these parameters, was seen only at micromolar concentrations. These results indicate that both Sm-C and insulin acting through the receptors increase Leydig cell steroidogenic responsiveness to hCG by increasing hCG receptor number and improving some step beyond cAMP formation. In contrast, the mitogenic effects of insulin are mediated only through Sm-C receptors.« less

Insulin sensitizers prevent fine particulate matter-induced vascular insulin resistance and changes in endothelial progenitor cell homeostasis.

PubMed

Haberzettl, Petra; McCracken, James P; Bhatnagar, Aruni; Conklin, Daniel J

2016-06-01

Exposure to fine particular matter (PM2.5) increases the risk of developing cardiovascular disease and Type 2 diabetes. Because blood vessels are sensitive targets of air pollutant exposure, we examined the effects of concentrated ambient PM2.5 (CAP) on vascular insulin sensitivity and circulating levels of endothelial progenitor cells (EPCs), which reflect cardiovascular health. We found that CAP exposure for 9 days decreased insulin-stimulated Akt phosphorylation in the aorta of mice maintained on control diet. This change was accompanied by the induction of IL-1β and increases in the abundance of cleaved IL-18 and p10 subunit of Casp-1, consistent with the activation of the inflammasome pathway. CAP exposure also suppressed circulating levels of EPCs (Flk-1(+)/Sca-1(+) cells), while enhancing the bone marrow abundance of these cells. Although similar changes in vascular insulin signaling and EPC levels were observed in mice fed high-fat diet, CAP exposure did not exacerbate diet-induced changes in vascular insulin resistance or EPC homeostasis. Treatment with an insulin sensitizer, metformin or rosiglitazone, prevented CAP-induced vascular insulin resistance and NF-κB and inflammasome activation and restored peripheral blood and bone marrow EPC levels. These findings suggest that PM2.5 exposure induces diet-independent vascular insulin resistance and inflammation and prevents EPC mobilization, and that this EPC mobilization defect could be mediated by vascular insulin resistance. Impaired vascular insulin sensitivity may be an important mechanism underlying PM2.5-induced vascular injury, and pharmacological sensitization to insulin action could potentially prevent deficits in vascular repair and mitigate vascular inflammation due to exposure to elevated levels of ambient air pollution. Copyright © 2016 the American Physiological Society.

The transcription factor Prep1 controls hepatic insulin sensitivity and gluconeogenesis by targeting nuclear localization of FOXO1.

PubMed

Kulebyakin, Konstantin; Penkov, Dmitry; Blasi, Francesco; Akopyan, Zhanna; Tkachuk, Vsevolod

2016-12-02

Liver plays a key role in controlling body carbohydrate homeostasis by switching between accumulation and production of glucose and this way maintaining constant level of glucose in blood. Increased blood glucose level triggers release of insulin from pancreatic β-cells. Insulin represses hepatic glucose production and increases glucose accumulation. Insulin resistance is the main cause of type 2 diabetes and hyperglycemia. Currently thiazolidinediones (TZDs) targeting transcriptional factor PPARγ are used as insulin sensitizers for treating patients with type 2 diabetes. However, TZDs are reported to be associated with cardiovascular and liver problems and stimulate obesity. Thus, it is necessary to search new approaches to improve insulin sensitivity. A promising candidate is transcriptional factor Prep1, as it was shown earlier it could affect insulin sensitivity in variety of insulin-sensitive tissues. The aim of the present study was to evaluate a possible involvement of transcriptional factor Prep1 in control of hepatic glucose accumulation and production. We created mice with liver-specific Prep1 knockout and discovered that hepatocytes derived from these mice are much more sensitive to insulin, comparing to their WT littermates. Incubation of these cells with 100 nM insulin results in almost complete inhibition of gluconeogenesis, while in WT cells this repression is only partial. However, Prep1 doesn't affect gluconeogenesis in the absence of insulin. Also, we observed that nuclear content of gluconeogenic transcription factor FOXO1 was greatly reduced in Prep1 knockout hepatocytes. These findings suggest that Prep1 may control hepatic insulin sensitivity by targeting FOXO1 nuclear stability. Copyright © 2016 Elsevier Inc. All rights reserved.

Insulin degludec/insulin aspart combination for the treatment of type 1 and type 2 diabetes

PubMed Central

Dardano, Angela; Bianchi, Cristina; Del Prato, Stefano; Miccoli, Roberto

2014-01-01

Glycemic control remains the major therapeutic objective to prevent or delay the onset and progression of complications related to diabetes mellitus. Insulin therapy represents a cornerstone in the treatment of diabetes and has been used widely for achieving glycemic goals. Nevertheless, a large portion of the population with diabetes does not meet the internationally agreed glycemic targets. Moreover, insulin treatment, especially if intensive, may be associated with emergency room visits and hospitalization due to hypoglycemic events. Therefore, fear of hypoglycemia or hypoglycemic events represents the main barriers to the attainment of glycemic targets. The burden associated with multiple daily injections also remains a significant obstacle to initiating and maintaining insulin therapy. The most attractive insulin treatment approach should meet the patients’ preference, rather than demanding patients to change or adapt their lifestyle. Insulin degludec/insulin aspart (IDegAsp) is a new combination, formulated with ultra-long-acting insulin degludec and rapid-acting insulin aspart, with peculiar pharmacological features, clinical efficacy, safety, and tolerability. IDegAsp provides similar, noninferior glycemic control to a standard basal–bolus regimen in patients with type 1 diabetes mellitus, with additional benefits of significantly lower episodes of hypoglycemia (particularly nocturnal) and fewer daily insulin injections. Moreover, although treatment strategy and patients’ viewpoint are different in type 1 and type 2 diabetes, trial results suggest that IDegAsp may be an appropriate and reasonable option for initiating insulin therapy in patients with type 2 diabetes inadequately controlled on maximal doses of conventional oral agents. This paper will discuss the role of IDegAsp combination as a novel treatment option in diabetic patients. PMID:25143741

Differential regulation of protein synthesis by amino acids and insulin in peripheral and visceral tissues of neonatal pigs

PubMed Central

Suryawan, Agus; O’Connor, Pamela M. J.; Bush, Jill A.; Nguyen, Hanh V.

2009-01-01

The high efficiency of protein deposition during the neonatal period is driven by high rates of protein synthesis, which are maximally stimulated after feeding. In the current study, we examined the individual roles of amino acids and insulin in the regulation of protein synthesis in peripheral and visceral tissues of the neonate by performing pancreatic glucose–amino acid clamps in overnight-fasted 7-day-old pigs. We infused pigs (n = 8–12/group) with insulin at 0, 10, 22, and 110 ng kg−0.66 min−1 to achieve ~0, 2, 6 and 30 μU ml−1 insulin so as to simulate below fasting, fasting, intermediate, and fed insulin levels, respectively. At each insulin dose, amino acids were maintained at the fasting or fed level. In conjunction with the highest insulin dose, amino acids were also allowed to fall below the fasting level. Tissue protein synthesis was measured using a flooding dose of L-[4-3H] phenylalanine. Both insulin and amino acids increased fractional rates of protein synthesis in longissimus dorsi, gastrocnemius, masseter, and diaphragm muscles. Insulin, but not amino acids, increased protein synthesis in the skin. Amino acids, but not insulin, increased protein synthesis in the liver, pancreas, spleen, and lung and tended to increase protein synthesis in the jejunum and kidney. Neither insulin nor amino acids altered protein synthesis in the stomach. The results suggest that the stimulation of protein synthesis by feeding in most tissues of the neonate is regulated by the post-prandial rise in amino acids. However, the feeding-induced stimulation of protein synthesis in skeletal muscles is independently mediated by insulin as well as amino acids. PMID:18683020

Patient-level meta-analysis of efficacy and hypoglycaemia in people with type 2 diabetes initiating insulin glargine 100U/mL or neutral protamine Hagedorn insulin analysed according to concomitant oral antidiabetes therapy.

PubMed

Owens, David R; Traylor, Louise; Mullins, Peter; Landgraf, Wolfgang

2017-02-01

Evaluate efficacy and hypoglycaemia according to concomitant oral antidiabetes drug (OAD) in people with type 2 diabetes initiating insulin glargine 100U/mL (Gla-100) or neutral protamine Hagedorn (NPH) insulin once daily. Four studies (target fasting plasma glucose [FPG] ⩽100mg/dL [⩽5.6mmol/L]; duration ⩾24weeks) were included. Standardised data from 2091 subjects (Gla-100, n=1024; NPH insulin, n=1067) were analysed. Endpoints included glycated haemoglobin (HbA1c) and FPG change, glycaemic target achievement, hypoglycaemia, weight change, and insulin dose. Mean HbA1c and FPG reductions were similar with Gla-100 and NPH insulin regardless of concomitant OAD (P=0.184 and P=0.553, respectively) and similar proportions of subjects achieved HbA1c <7.0% (P=0.603). There was a trend for more subjects treated with Gla-100 achieving FPG ⩽100mg/dL versus NPH insulin (relative risk [RR] 1.09 [95% confidence interval (CI) 0.97-1.23]; P=0.135). Plasma glucose confirmed (<70mg/dL) overall and nocturnal hypoglycaemia incidences and rates were lower with Gla-100 versus NPH insulin (overall RR 0.93 [95% CI 0.87-1.00]; P=0.041; nocturnal RR 0.73 [95% CI 0.65-0.83]; P<0.001). After 24weeks, weight gain and insulin doses were higher with Gla-100 versus NPH insulin (2.7kg vs 2.3kg, P=0.009 and 0.42U/kg vs 0.39U/kg; P=0.003, respectively). Insulin doses were higher when either insulin was added to sulfonylurea alone. Pooled results from treat-to-target trials in insulin-naïve people with type 2 diabetes demonstrate a significantly lower overall and nocturnal hypoglycaemia risk across different plasma glucose definitions with Gla-100 versus NPH insulin at similar glycaemic control. OAD therapy co-administered with Gla-100 or NPH insulin impacts glycaemic control and overall nocturnal hypoglycaemia risk. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Effects of prenatal caffeine exposure on glucose homeostasis of adult offspring rats

NASA Astrophysics Data System (ADS)

Kou, Hao; Wang, Gui-hua; Pei, Lin-guo; Zhang, Li; Shi, Chai; Guo, Yu; Wu, Dong-fang; Wang, Hui

2017-12-01

Epidemiological evidences show that prenatal caffeine exposure (PCE) could induce intrauterine growth retardation (IUGR). The IUGR offspring also present glucose intolerance and type 2 diabetes mellitus after maturity. We have previously demonstrated that PCE induced IUGR and increased susceptibility to adult metabolic syndrome in rats. This study aimed to further investigate the effects of PCE on glucose homeostasis in adult offspring rats. Pregnant rats were administered caffeine (120 mg/kg/day, intragastrically) from gestational days 11 to 20. PCE offspring presented partial catch-up growth pattern after birth, characterizing by the increased body weight gain rates. Meanwhile, PCE had no significant influences on the basal blood glucose and insulin phenotypes of adult offspring but increased the glucose tolerance, glucose-stimulated insulin section and β cell sensitivity to glucose in female progeny. The insulin sensitivity of both male and female PCE offspring were enhanced accompanied with reduced β cell fraction and mass. Western blotting results revealed that significant augmentation in protein expression of hepatic insulin signaling elements of PCE females, including insulin receptor (INSR), insulin receptor substrate 1 (IRS-1) and the phosphorylation of serine-threonine protein kinase (Akt), was also potentiated. In conclusion, we demonstrated that PCE reduced the pancreatic β mass but increased the glucose tolerance in adult offspring rats, especially for females. The adaptive compensatory enhancement of β cell responsiveness to glucose and elevated insulin sensitivity mainly mediated by upregulated hepatic insulin signaling might coordinately contribute to the increased glucose tolerance.

Obesity-induced diabetes in mouse strains treated with gold thioglucose: a novel animal model for studying β-cell dysfunction.

PubMed

Karasawa, Hiroshi; Takaishi, Kiyosumi; Kumagae, Yoshihiro

2011-03-01

An obesity-induced diabetes model using genetically normal mouse strains would be invaluable but remains to be established. One reason is that several normal mouse strains are resistant to high-fat diet-induced obesity. In the present study, we show the effectiveness of gold thioglucose (GTG) in inducing hyperphagia and severe obesity in mice, and demonstrate the development of obesity-induced diabetes in genetically normal mouse strains. GTG treated DBA/2, C57BLKs, and BDF1 mice gained weight rapidly and exhibited significant increases in nonfasting plasma glucose levels 8-12 weeks after GTG treatment. These mice showed significantly impaired insulin secretion, particularly in the early phase after glucose load, and reduced insulin content in pancreatic islets. Interestingly, GTG treated C57BL/6 mice did not become diabetic and retained normal early insulin secretion and islet insulin content despite being as severely obese and insulin resistant as the other mice. These results suggest that the pathogenesis of obesity-induced diabetes in GTG-treated mice is attributable to the inability of their pancreatic β-cells to secrete enough insulin to compensate for insulin resistance. Mice developing obesity-induced diabetes after GTG treatment might be a valuable tool for investigating obesity-induced diabetes. Furthermore, comparing the genetic backgrounds of mice with different susceptibilities to diabetes may lead to the identification of novel genetic factors influencing the ability of pancreatic β-cells to secrete insulin.

Effects of insulin on wound healing: A review of animal and human evidences.

PubMed

Oryan, Ahmad; Alemzadeh, Esmat

2017-04-01

Several studies have indicated that insulin that is used in reducing blood glucose is also affective on wound healing by various mechanisms. To understand the outcomes of insulin therapy on wound healing, a meta-analysis and systematic review was performed. The Cochrane library, PubMed, and Science Direct were searched for the literature published from January the 1st 1990 to September the 30th 2016. Twelve animals and nine clinical studies were included. A quantitative and qualitative review was performed on the clinical trials and the animal studies were comprehensively overviewed. Statistical analysis for development of granulation tissue, microvessel density, and time of healing was conducted in this systematic review. The animal studies revealed that treatment with topical insulin lead to faster wound contraction and re-epithelialization. Meta-analysis of wound studies revealed that insulin therapy is significantly favored for growth of granulation tissue. Based on these findings, insulin enhanced development of granulation tissue on day 7 after treatment. The meta-analysis studies indicated significant reduction in time of healing in the patients treated with insulin. These studies also disclosed that the new vessels were observable from five days after injection in the treated group, compared to the control animals that developed significantly at later stage. Insulin is a low cost growth factor and can be considered as a therapeutic agent in wound healing. However, further studies are necessary to gain a better understanding of the role of insulin in wound healing. Copyright © 2017 Elsevier Inc. All rights reserved.

Predictors of Gestational Diabetes Mellitus in Chinese Women with Polycystic Ovary Syndrome: A Cross-Sectional Study.

PubMed

Zhang, Ya-Jie; Jin, Hua; Qin, Zhen-Li; Ma, Jin-Long; Zhao, Han; Zhang, Ling; Chen, Zi-Jiang

2016-01-01

This study aims to explore the independent predictors of gestational diabetes mellitus (GDM) in Chinese women with polycystic ovary syndrome (PCOS). This cross-sectional study analyzed primigravid women with PCOS and classified them as those with and without GDM. Independent risk factors and model performance were analyzed using multivariate logistic regression and the area under the curve (AUC) of receiver operating characteristic (ROC), respectively. Maternal body mass index, waist circumference, waist-to-hip ratio (WHR), fasting glucose, insulin, sex hormone-binding globulin (SHBG), homeostasis model assessment-insulin resistance (HOMA-IR) before pregnancy, gestation weight gain before 24 weeks and the incidence of family history of diabetes were different in the 2 groups. Logistic regression analysis showed that pre-pregnancy WHR, SHBG, HOMA-IR and gestation weight gain before 24 weeks were the independent predictors of GDM. ROC curve analysis confirmed that gestation weight gain before 24 weeks (AUC 0.767, 95% CI 0.688-0.841), pre-pregnant WHR (AUC 0.725, 95% CI 0.649-0.802), HOMA-IR (AUC 0.711, 95% CI 0.632-0.790) and SHBG levels (AUC 0.709, 95% CI 0.625-0.793) were the strong risk factors. In Chinese women with PCOS, factors of gestation weight gain before 24 weeks, pre-pregnant WHR, HOMA-IR and SHBG levels are strongly associated with subsequent development of GDM. © 2015 S. Karger AG, Basel.

Biological assessment of self-assembled polymeric micelles for pulmonary administration of insulin.

PubMed

Andrade, Fernanda; das Neves, José; Gener, Petra; Schwartz, Simó; Ferreira, Domingos; Oliva, Mireia; Sarmento, Bruno

2015-10-01

Pulmonary delivery of drugs for both local and systemic action has gained new attention over the last decades. In this work, different amphiphilic polymers (Soluplus®, Pluronic® F68, Pluronic® F108 and Pluronic® F127) were used to produce lyophilized formulations for inhalation of insulin. Development of stimuli-responsive, namely glucose-sensitive, formulations was also attempted with the addition of phenylboronic acid (PBA). Despite influencing the in vitro release of insulin from micelles, PBA did not confer glucose-sensitive properties to formulations. Lyophilized powders with aerodynamic diameter (<6 μm) compatible with good deposition in the lungs did not present significant in vitro toxicity for respiratory cell lines. Additionally, some formulations, in particular Pluronic® F127-based formulations, enhanced the permeation of insulin through pulmonary epithelial models and underwent minimal internalization by macrophages in vitro. Overall, formulations based on polymeric micelles presenting promising characteristics were developed for the delivery of insulin by inhalation. The ability to deliver other systemic drugs via inhalation has received renewed interests in the clinical setting. This is especially true for drugs which usually require injections for delivery, like insulin. In this article, the authors investigated their previously developed amphiphilic polymers for inhalation of insulin in an in vitro model. The results should provide basis for future in vivo studies. Copyright © 2015 Elsevier Inc. All rights reserved.

Protein quality and quantity and insulin control of mammary gland glucose utilization during lactation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Masor, M.L.

1987-01-01

Virgin Sprague-Dawley rats were bred, and fed laboratory stock (STOCK), 13% casein plus methionine, 13% wheat gluten, or 5% casein plus methionine through gestation and 4 days of lactation. Diets were switched at parturition to determine the effects of dietary protein quality and quantity fed during gestation and/or lactation on insulin stimulation of mammary glucose utilization. On day 20 of gestation (20G) and day 4 of lactation (4L) the right inguinal-abdominal mammary glands were removed, and acini and tissue slices were incubated in Krebs buffer with or without insulin containing (U-/sup 14/C)-glucose and 5mM glucose for 1 hour at 37/degrees/C.more » Glucose incorporation into CO/sub 2/, lipid and lactose was determined. Glucose incorporation into CO/sub 2/ and lipid, but not lactose was stimulated by insulin in mammary slices. Diet effects on glucose utilization in acini were confirmed in slices for basal and insulin stimulated levels. Treatment affected the absolute increase of insulin stimulation. Regression analysis significantly correlated pup weight gain with total glucose utilization. Poor dietary protein quality and quantity fed during gestation impaired both overall response of mammary glucose utilization to insulin stimulation, and mammary development during pregnancy. Improving protein value at parturition did not overcome those deficits by 4L.« less

Exercise training reverses the negative effects of chronic L-arginine supplementation on insulin sensitivity.

PubMed

Salgueiro, Rafael Barrera; Gerlinger-Romero, Frederico; Guimarães-Ferreira, Lucas; de Castro Barbosa, Thais; Nunes, Maria Tereza

2017-12-15

L-Arginine has emerged as an important supplement for athletes and non-athletes in order to improve performance. Arginine has been extensively used as substrate for nitric oxide synthesis, leading to increased vasodilatation and hormonal secretion. However, the chronic consumption of arginine has been shown to impair insulin sensitivity. In the present study, we aimed to evaluate whether chronic arginine supplementation associated with exercise training would have a beneficial impact on insulin sensitivity. We, therefore, treated Wistar rats for 4weeks with arginine, associated or not with exercise training (treadmill). We assessed the somatotropic activation, by evaluating growth hormone (GH) gene expression and protein content in the pituitary, as well is GH concentration in the serum. Additionally, we evaluate whole-body insulin sensitivity, by performing an insulin tolerance test. Skeletal muscle morpho-physiological parameters were also assessed. Insulin sensitivity was impaired in the arginine-treated rats. However, exercise training reversed the negative effects of arginine. Arginine and exercise training increased somatotropic axis function, muscle mass and body weight gain. The combination arginine and exercise training further decreased total fat mass. Our results confirm that chronic arginine supplementation leads to insulin resistance, which can be reversed in the association with exercise training. We provide further evidence that exercise training is an important tool to improve whole-body metabolism. Copyright © 2017 Elsevier Inc. All rights reserved.

A review of the safety and efficacy data for insulin glargine 300 units/ml, a new formulation of insulin glargine.

PubMed

Dailey, G; Lavernia, F

2015-12-01

Insulin glargine 100 units/ml (Gla-100) has become a standard of care in diabetes treatment over the past decade, providing 24-h basal insulin coverage after once-daily subcutaneous injection for many people with diabetes, with a well-established efficacy and safety profile. New insulin glargine 300 units/ml (Gla-300) is a basal insulin that provides the same number of units as Gla-100 in a third of the volume. Compared with Gla-100, Gla-300 has shown more constant and prolonged pharmacokinetic (PK)/pharmacodynamic (PD) profiles. This review summarizes the findings from the EDITION series of clinical trials that investigated Gla-300 in individuals with type 1 and type 2 diabetes mellitus. Overall, Gla-300 has been shown to achieve similar glycaemic control with less, or similar, nocturnal hypoglycaemia compared with Gla-100, and a trend towards lower hypoglycaemia at any time of day. The EDITION series of clinical trials also provides some evidence for less weight gain with Gla-300 than with Gla-100. In addition, the PK/PD profiles of Gla-300 may allow more flexibility in the timing of doses, improving convenience; thus, Gla-300 could offer several positive features for individuals with diabetes requiring basal insulin therapy. © 2015 John Wiley & Sons Ltd.

Radiofrequency radiation emitted from Wi-Fi (2.4 GHz) causes impaired insulin secretion and increased oxidative stress in rat pancreatic islets.

PubMed

Masoumi, Ali; Karbalaei, Narges; Mortazavi, S M J; Shabani, Mohammad

2018-06-18

There is a great concern regarding the possible adverse effects of electromagnetic radiation (EMR). This study investigated the effects of EMR induced by Wi-Fi (2.45GHz) on insulin secretion and antioxidant redox systems in the rat pancreas. Adult male Sprague-Dawley rats in the weight range of 230 to 260 g were divided into control, sham, Wi-Fi exposed groups. After long term exposure (4 h/day for 45 days) to Wi-Fi electromagnetic radiation, plasma levels of glucose and insulin during intraperitoneal glucose tolerance test were measured. Islet insulin secretion and content, lipid peroxidation and antioxidant status in pancreas of rats were determined. Our data showed that the weight gain in the WI-FI exposed group was significantly lower than the control group (p<0.05). Wi-Fi (2.45 GHz) exposed group showed hyperglycemia. Plasma insulin level and glucose-stimulated insulin secretion from pancreatic islet were significantly reduced in the Wi-Fi exposed group. EMR emitted from Wi-Fi caused a significant increase in lipid peroxidation and a significant decrease in GSH level, SOD and GPx activities of the pancreas. these data showed that EMR of Wi-Fi leads to hyperglycemia, increased oxidative stress and impaired insulin secretion in the rat pancreatic islets.

Identification of the mechanism of action of a glucokinase activator from oral glucose tolerance test data in type 2 diabetic patients based on an integrated glucose-insulin model.

PubMed

Jauslin, Petra M; Karlsson, Mats O; Frey, Nicolas

2012-12-01

A mechanistic drug-disease model was developed on the basis of a previously published integrated glucose-insulin model by Jauslin et al. A glucokinase activator was used as a test compound to evaluate the model's ability to identify a drug's mechanism of action and estimate its effects on glucose and insulin profiles following oral glucose tolerance tests. A kinetic-pharmacodynamic approach was chosen to describe the drug's pharmacodynamic effects in a dose-response-time model. Four possible mechanisms of action of antidiabetic drugs were evaluated, and the corresponding affected model parameters were identified: insulin secretion, glucose production, insulin effect on glucose elimination, and insulin-independent glucose elimination. Inclusion of drug effects in the model at these sites of action was first tested one-by-one and then in combination. The results demonstrate the ability of this model to identify the dual mechanism of action of a glucokinase activator and describe and predict its effects: Estimating a stimulating drug effect on insulin secretion and an inhibiting effect on glucose output resulted in a significantly better model fit than any other combination of effect sites. The model may be used for dose finding in early clinical drug development and for gaining more insight into a drug candidate's mechanism of action.

Peripheral Blood Transcriptomic Signatures of Fasting Glucose and Insulin Concentrations

PubMed Central

Chen, Brian H.; Hivert, Marie-France; Peters, Marjolein J.; Pilling, Luke C.; Hogan, John D.; Pham, Lisa M.; Harries, Lorna W.; Fox, Caroline S.; Bandinelli, Stefania; Dehghan, Abbas; Hernandez, Dena G.; Hofman, Albert; Hong, Jaeyoung; Joehanes, Roby; Johnson, Andrew D.; Munson, Peter J.; Rybin, Denis V.; Singleton, Andrew B.; Uitterlinden, André G.; Ying, Saixia; Melzer, David; Levy, Daniel; van Meurs, Joyce B.J.; Ferrucci, Luigi; Florez, Jose C.; Dupuis, Josée

2016-01-01

Genome-wide association studies (GWAS) have successfully identified genetic loci associated with glycemic traits. However, characterizing the functional significance of these loci has proven challenging. We sought to gain insights into the regulation of fasting insulin and fasting glucose through the use of gene expression microarray data from peripheral blood samples of participants without diabetes in the Framingham Heart Study (FHS) (n = 5,056), the Rotterdam Study (RS) (n = 723), and the InCHIANTI Study (Invecchiare in Chianti) (n = 595). Using a false discovery rate q <0.05, we identified three transcripts associated with fasting glucose and 433 transcripts associated with fasting insulin levels after adjusting for age, sex, technical covariates, and complete blood cell counts. Among the findings, circulating IGF2BP2 transcript levels were positively associated with fasting insulin in both the FHS and RS. Using 1000 Genomes–imputed genotype data, we identified 47,587 cis-expression quantitative trait loci (eQTL) and 6,695 trans-eQTL associated with the 433 significant insulin-associated transcripts. Of note, we identified a trans-eQTL (rs592423), where the A allele was associated with higher IGF2BP2 levels and with fasting insulin in an independent genetic meta-analysis comprised of 50,823 individuals. We conclude that integration of genomic and transcriptomic data implicate circulating IGF2BP2 mRNA levels associated with glucose and insulin homeostasis. PMID:27625022

Development of diet-induced insulin resistance in adult Drosophila melanogaster

PubMed Central

Morris, Siti Nur Sarah; Coogan, Claire; Chamseddin, Khalil; Fernandez-Kim, Sun Ok; Kolli, Santharam; Keller, Jeffrey N.; Bauer, Johannes H.

2013-01-01

The fruit fly Drosophila melanogaster is increasingly utilized as an alternative to costly rodent models to study human diseases. Fly models exist for a wide variety of human conditions, such as Alzheimer's and Parkinson’s Disease, or cardiac function. Advantages of the fly system are its rapid generation time and its low cost. However, the greatest strength of the fly system are the powerful genetic tools that allow for rapid dissection of molecular disease mechanisms. Here, we describe the diet-dependent development of metabolic phenotypes in adult fruit flies. Depending on the specific type of nutrient, as well as its relative quantity in the diet, flies show weight gain and changes in the levels of storage macromolecules. Furthermore, the activity of insulin-signaling in the major metabolic organ of the fly, the fat body, decreases upon overfeeding. This decrease in insulin-signaling activity in overfed flies is moreover observed when flies are challenged with an acute food stimulus, suggesting that overfeeding leads to insulin resistance. Similar changes were observed in aging flies, with the development of the insulin resistance-like phenotype beginning at early middle ages. Taken together, these data demonstrate that imbalanced diet disrupts metabolic homeostasis in adult D. melanogaster and promotes insulin-resistant phenotypes. Therefore, the fly system may be a useful alternative tool in the investigation of molecular mechanisms of insulin resistance and the development of pharmacologic treatment options. PMID:22542511

Pancreatic Islet Responses to Metabolic Trauma

PubMed Central

Burke, Susan J.; Karlstad, Michael D.; Collier, J. Jason

2016-01-01

Carbohydrate, lipid, and protein metabolism are largely controlled by the interplay of various hormones, which includes those secreted by the pancreatic islets of Langerhans. While typically representing only 1–2% of the total pancreatic mass, the islets have a remarkable ability to adapt to disparate situations demanding a change in hormone release, such as peripheral insulin resistance. There are many different routes to the onset of insulin resistance, including obesity, lipodystrophy, glucocorticoid excess, and the chronic usage of atypical anti-psychotic drugs. All of these situations are coupled to an increase in pancreatic islet size, often with a corresponding increase in insulin production. These adaptive responses within the islets are ultimately intended to maintain glycemic control and to promote macronutrient homeostasis during times of stress. Herein, we review the consequences of specific metabolic trauma that lead to insulin resistance and the corresponding adaptive alterations within the pancreatic islets. PMID:26974425

Effects of dehydroepiandrosterone in rats injected with streptozotocin during the neonatal period.

PubMed

Giroix, M H; Malaisse-Lagae, F; Portha, B; Sener, A; Malaisse, W J

1997-06-01

Control rats and diabetic animals injected with streptozotocin during the neonatal period were either maintained on a standard diet or given access to food supplemented with dehydroepiandrosterone (DHEA, 0.2%) for 11 days before sacrifice. In both control and diabetic rats, DHEA feeding augmented the activity of the mitochondrial FAD-linked glycerophosphate dehydrogenase and cytosolic NADP-linked malate dehydrogenase in liver, but not so in either the parotid gland or pancreatic islets. DHEA lowered, in both control and diabetic rats, the ratio between D-glucose oxidation and utilization and the rate of insulin release in pancreatic islets exposed to a high concentration of D-glucose, as well as the insulin concentration and insulin/glucose ratio in plasma. These findings support the view that, in diabetes, DHEA, by increasing sensitivity to insulin, may allow islet B-cells to avoid the otherwise unfavorable consequences of chronic hyperactivity.

Chronic combined hyperandrogenemia and western-style diet in young female rhesus macaques causes greater metabolic impairments compared to either treatment alone.

PubMed

True, C A; Takahashi, D L; Burns, S E; Mishler, E C; Bond, K R; Wilcox, M C; Calhoun, A R; Bader, L A; Dean, T A; Ryan, N D; Slayden, O D; Cameron, J L; Stouffer, R L

2017-09-01

Does developmental exposure to the combination of hyperandrogenemia and western-style diet (WSD) worsen adult metabolic function compared to either treatment alone? Young female rhesus macaques treated for 3 years, beginning at menarche, with combined testosterone (T) and WSD have increased weight gain and insulin resistance compared to controls and animals treated with either T or WSD alone. Hyperandrogenemia is a well-established component of polycystic ovary syndrome (PCOS) and can be observed in peripubertal girls, indicating a potential pubertal onset of the disease. Obesity is often associated with hyperandrogenemia in peripubertal girls, and overweight girls appear to be at higher risk for the development of PCOS later in life. Juvenile (2.5- year old) female rhesus macaques were divided into four groups (n = 10/group): control animals receiving cholesterol implants and a control diet with 15% of calories derived from fat (C), animals receiving T implants (mean serum levels: 1.35 ± 0.01 ng/ml) and a control diet (T), animals receiving a cholesterol implant and a WSD with 36% of calories derived from fat (WSD) and animals receiving a T implant and a WSD (T + WSD). Animals were maintained on the treatments for 36 months and were 5.5 years old at study completion. Metabolic testing consisted of body measurements including weight, dual-energy X-ray absorptiometry scans, activity monitoring, and glucose tolerance testing at zero months and at least once every 12 months for the remainder of the study. Indirect calorimetry and serum hormone assays were performed following 36 months of treatment. Body weight and fat mass gain were significantly increased in T + WSD at 24 and 36 months of treatment compared to the other three groups. Log transformed fasting insulin and Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) were significantly increased in T + WSD animals at 3 years of treatment compared to all other groups. T-treatment caused a greater rate of decline in activity after 18 months, while food intake and metabolic rate were largely unaffected by treatments. Variability was present in the metabolic parameters measured; however, this is similar to the heterogeneity observed in human populations. Chronic hyperandrogenemia beginning at puberty may exacerbate metabolic dysfunction in women consuming a WSD and account for the increased rates of obesity and insulin resistance observed in PCOS patients. Counseling of female patient populations with elevated androgens about the potential benefit of consuming a lower fat diet could improve long-term metabolic health outcomes. Eunice Kennedy Shriver National Institute of Child Health & Human Development P50HD071836 and Oregon National Primate Center Grant P51 OD011092. The authors have no competing conflict of interests to disclose. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

rDNA insulin glargine U300 – a critical appraisal

PubMed Central

Wang, Fei; Zassman, Stefanie; Goldberg, Philip A

2016-01-01

Background As the first once-daily basal insulin analog, insulin glargine 100 U/mL (Gla-100; Lantus®) rapidly evolved into the most commonly prescribed insulin therapy worldwide. However, this insulin has clinical limitations. The approval of new basal insulin analogs in 2015 has already started to alter the prescribing landscape. Objective To review the available evidence on the clinical efficacy and safety of a more concentrated insulin glargine (recombinant DNA origin) injection 300 U/mL (Gla-300) compared to insulin Gla-100 in patients with type 1 and type 2 diabetes mellitus (T1DM and T2DM). Methods The following electronic databases were searched: PubMed and MEDLINE (using Ovid platform), Scopus, BIOSIS, and Google Scholar through June 2016. Conference proceedings of the American Diabetes Association (2015–2016) were reviewed. We also manually searched reference lists of pertinent reviews and trials. Results A total of 6 pivotal Phase III randomized controlled trials known as the EDITION series were reviewed. All of these trials (n=3,500) were head-to-head comparisons evaluating the efficacy and tolerability of Gla-300 vs Gla-100 in a diverse population with T1DM and T2DM. These trials were of 6 months duration with a 6-month safety extension phase. Conclusion Gla-300 was as effective as Gla-100 for improving glycemic control over 6 months in all studies, with a lower risk of nocturnal hypoglycemia significant only in insulin-experienced patients with T2DM. Overall, patients on Gla-300 required 10%–18% more basal insulin, but with less weight gain compared with Gla-100. PMID:27980431

SGLT2-inhibitor and DPP-4 inhibitor improve brain function via attenuating mitochondrial dysfunction, insulin resistance, inflammation, and apoptosis in HFD-induced obese rats.

PubMed

Sa-Nguanmoo, Piangkwan; Tanajak, Pongpan; Kerdphoo, Sasiwan; Jaiwongkam, Thidarat; Pratchayasakul, Wasana; Chattipakorn, Nipon; Chattipakorn, Siriporn C

2017-10-15

Dipeptidyl peptidase-4 inhibitor (vildagliptin) has been shown to exert beneficial effects on insulin sensitivity and neuroprotection in obese-insulin resistance. Recent studies demonstrated the neuroprotection of the sodium-glucose co-transporter 2 inhibitor (dapagliflozin) in diabetes. However, the comparative effects of both drugs and a combination of two drugs on metabolic dysfunction and brain dysfunction impaired by the obese-insulin resistance have never been investigated. Forty male Wistar rats were divided into two groups, and received either a normal-diet (ND, n=8) or a high-fat diet (HFD, n=32) for 16weeks. At week 13, the HFD-fed rats were divided into four subgroups (n=8/subgroup) to receive either a vehicle, vildagliptin (3mg/kg/day) dapagliflozin (1mg/kg/day) or combined drugs for four weeks. ND rats were given a vehicle for four weeks. Metabolic parameters and brain function were investigated. The results demonstrated that HFD rats developed obese-insulin resistance and cognitive decline. Dapagliflozin had greater efficacy on improved peripheral insulin sensitivity and reduced weight gain than vildagliptin. Single therapy resulted in equally improved brain mitochondrial function, insulin signaling, apoptosis and prevented cognitive decline. However, only dapagliflozin improved hippocampal synaptic plasticity. A combination of the drugs had greater efficacy in improving brain insulin sensitivity and reducing brain oxidative stress than the single drug therapy. These findings suggested that dapagliflozin and vildagliptin equally prevented cognitive decline in the obese-insulin resistance, possibly through some similar mechanisms. Dapagliflozin had greater efficacy than vildagliptin for preserving synaptic plasticity, thus combined drugs could be the best therapeutic approach for neuroprotection in the obese-insulin resistance. Copyright © 2017 Elsevier Inc. All rights reserved.

Evaluation of the long-term cost-effectiveness of IDegLira versus liraglutide added to basal insulin for patients with type 2 diabetes failing to achieve glycemic control on basal insulin in the USA.

PubMed

Hunt, B; Mocarski, M; Valentine, W J; Langer, J

2017-07-01

IDegLira, a fixed ratio combination of insulin degludec and glucagon-like peptide-1 receptor agonist liraglutide, utilizes the complementary mechanisms of action of these two agents to improve glycemic control with low risk of hypoglycemia and avoidance of weight gain. The aim of the present analysis was to assess the long-term cost-effectiveness of IDegLira vs liraglutide added to basal insulin, for patients with type 2 diabetes not achieving glycemic control on basal insulin in the US setting. Projections of lifetime costs and clinical outcomes were made using the IMS CORE Diabetes Model. Treatment effect data for patients receiving IDegLira and liraglutide added to basal insulin were modeled based on the outcomes of a published indirect comparison, as no head-to-head clinical trial data is currently available. Costs were accounted in 2015 US dollars ($) from a healthcare payer perspective. IDegLira was associated with small improvements in quality-adjusted life expectancy compared with liraglutide added to basal insulin (8.94 vs 8.91 discounted quality-adjusted life years [QALYs]). The key driver of improved clinical outcomes was the greater reduction in glycated hemoglobin associated with IDegLira. IDegLira was associated with mean costs savings of $17,687 over patient lifetimes vs liraglutide added to basal insulin, resulting from lower treatment costs and cost savings as a result of complications avoided. The present long-term modeling analysis found that IDegLira was dominant vs liraglutide added to basal insulin for patients with type 2 diabetes failing to achieve glycemic control on basal insulin in the US, improving clinical outcomes and reducing direct costs.

FoxO6 Integrates Insulin Signaling With Gluconeogenesis in the Liver

PubMed Central

Kim, Dae Hyun; Perdomo, German; Zhang, Ting; Slusher, Sandra; Lee, Sojin; Phillips, Brett E.; Fan, Yong; Giannoukakis, Nick; Gramignoli, Roberto; Strom, Stephen; Ringquist, Steven; Dong, H. Henry

2011-01-01

OBJECTIVE Excessive endogenous glucose production contributes to fasting hyperglycemia in diabetes. This effect stems from inept insulin suppression of hepatic gluconeogenesis. To understand the underlying mechanisms, we studied the ability of forkhead box O6 (FoxO6) to mediate insulin action on hepatic gluconeogenesis and its contribution to glucose metabolism. RESEARCH DESIGN AND METHODS We characterized FoxO6 in glucose metabolism in cultured hepatocytes and in rodent models of dietary obesity, insulin resistance, or insulin-deficient diabetes. We determined the effect of FoxO6 on hepatic gluconeogenesis in genetically modified mice with FoxO6 gain- versus loss-of-function and in diabetic db/db mice with selective FoxO6 ablation in the liver. RESULTS FoxO6 integrates insulin signaling to hepatic gluconeogenesis. In mice, elevated FoxO6 activity in the liver augments gluconeogenesis, raising fasting blood glucose levels, and hepatic FoxO6 depletion suppresses gluconeogenesis, resulting in fasting hypoglycemia. FoxO6 stimulates gluconeogenesis, which is counteracted by insulin. Insulin inhibits FoxO6 activity via a distinct mechanism by inducing its phosphorylation and disabling its transcriptional activity, without altering its subcellular distribution in hepatocytes. FoxO6 becomes deregulated in the insulin-resistant liver, accounting for its unbridled activity in promoting gluconeogenesis and correlating with the pathogenesis of fasting hyperglycemia in diabetes. These metabolic abnormalities, along with fasting hyperglycemia, are reversible by selective inhibition of hepatic FoxO6 activity in diabetic mice. CONCLUSIONS Our data uncover a FoxO6-dependent pathway by which the liver orchestrates insulin regulation of gluconeogenesis, providing the proof-of-concept that selective FoxO6 inhibition is beneficial for curbing excessive hepatic glucose production and improving glycemic control in diabetes. PMID:21940782

Increased Hepatic Glucose Production in Fetal Sheep With Intrauterine Growth Restriction Is Not Suppressed by Insulin

PubMed Central

Thorn, Stephanie R.; Brown, Laura D.; Rozance, Paul J.; Hay, William W.; Friedman, Jacob E.

2013-01-01

Intrauterine growth restriction (IUGR) increases the risk for metabolic disease and diabetes, although the developmental origins of this remain unclear. We measured glucose metabolism during basal and insulin clamp periods in a fetal sheep model of placental insufficiency and IUGR. Compared with control fetuses (CON), fetuses with IUGR had increased basal glucose production rates and hepatic PEPCK and glucose-6-phosphatase expression, which were not suppressed by insulin. In contrast, insulin significantly increased peripheral glucose utilization rates in CON and IUGR fetuses. Insulin robustly activated AKT, GSK3β, and forkhead box class O (FOXO)1 in CON and IUGR fetal livers. IUGR livers, however, had increased basal FOXO1 phosphorylation, nuclear FOXO1 expression, and Jun NH2-terminal kinase activation during hyperinsulinemia. Expression of peroxisome proliferator–activated receptor γ coactivator 1α and hepatocyte nuclear factor-4α were increased in IUGR livers during basal and insulin periods. Cortisol and norepinephrine concentrations were positively correlated with glucose production rates. Isolated IUGR hepatocytes maintained increased glucose production in culture. In summary, fetal sheep with IUGR have increased hepatic glucose production, which is not suppressed by insulin despite insulin sensitivity for peripheral glucose utilization. These data are consistent with a novel mechanism involving persistent transcriptional activation in the liver that seems to be unique in the fetus with IUGR. PMID:22933111

Characterization of Exercise and Alcohol Self-Management Behaviors of Type 1 Diabetes Patients on Insulin Pump Therapy.

PubMed

Grando, Maria Adela; Groat, Danielle; Soni, Hiral; Boyle, Mary; Bailey, Marilyn; Thompson, Bithika; Cook, Curtiss B

2017-03-01

There is a lack of systematic ways to analyze how diabetes patients use their insulin pumps to self-manage blood glucose to compensate for alcohol ingestion and exercise. The objective was to analyze "real-life" insulin dosing decisions occurring in conjunction with alcohol intake and exercise among patients using insulin pumps. We recruited adult type 1 diabetes (T1D) patients on insulin pump therapy. Participants were asked to maintain their daily routines, including those related to exercising and consuming alcohol, and keep a 30-day journal on exercise performed and alcohol consumed. Thirty days of insulin pump data were downloaded. Participants' actual insulin dosing behaviors were compared against their self-reported behaviors in the setting of exercise and alcohol. Nineteen T1D patients were recruited and over 4000 interactions with the insulin pump were analyzed. The analysis exposed variability in how subjects perceived the effects of exercise/alcohol on their blood glucose, inconsistencies between self-reported and observed behaviors, and higher rates of blood glucose control behaviors for exercise versus alcohol. Compensation techniques and perceptions on how exercise and alcohol affect their blood glucose levels vary between patients. Improved individualized educational techniques that take into consideration a patient's unique life style are needed to help patients effectively apply alcohol and exercise compensation techniques.

Muscle-specific PPARγ-deficient mice develop increased adiposity and insulin resistance but respond to thiazolidinediones

PubMed Central

Norris, Andrew W.; Chen, Lihong; Fisher, Simon J.; Szanto, Ildiko; Ristow, Michael; Jozsi, Alison C.; Hirshman, Michael F.; Rosen, Evan D.; Goodyear, Laurie J.; Gonzalez, Frank J.; Spiegelman, Bruce M.; Kahn, C. Ronald

2003-01-01

Activation of peroxisome proliferator-activated receptor γ (PPARγ) by thiazolidinediones (TZDs) improves insulin resistance by increasing insulin-stimulated glucose disposal in skeletal muscle. It remains debatable whether the effect of TZDs on muscle is direct or indirect via adipose tissue. We therefore generated mice with muscle-specific PPARγ knockout (MuPPARγKO) using Cre/loxP recombination. Interestingly, MuPPARγKO mice developed excess adiposity despite reduced dietary intake. Although insulin-stimulated glucose uptake in muscle was not impaired, MuPPARγKO mice had whole-body insulin resistance with a 36% reduction (P < 0.05) in the glucose infusion rate required to maintain euglycemia during hyperinsulinemic clamp, primarily due to dramatic impairment in hepatic insulin action. When placed on a high-fat diet, MuPPARγKO mice developed hyperinsulinemia and impaired glucose homeostasis identical to controls. Simultaneous treatment with TZD ameliorated these high fat–induced defects in MuPPARγKO mice to a degree identical to controls. There was also altered expression of several lipid metabolism genes in the muscle of MuPPARγKO mice. Thus, muscle PPARγ is not required for the antidiabetic effects of TZDs, but has a hitherto unsuspected role for maintenance of normal adiposity, whole-body insulin sensitivity, and hepatic insulin action. The tissue crosstalk mediating these effects is perhaps due to altered lipid metabolism in muscle. PMID:12925701

Chronic benzylamine administration in the drinking water improves glucose tolerance, reduces body weight gain and circulating cholesterol in high-fat diet-fed mice.

PubMed

Iffiú-Soltész, Zsuzsa; Wanecq, Estelle; Lomba, Almudena; Portillo, Maria P; Pellati, Federica; Szöko, Eva; Bour, Sandy; Woodley, John; Milagro, Fermin I; Alfredo Martinez, J; Valet, Philippe; Carpéné, Christian

2010-04-01

Benzylamine is found in Moringa oleifera, a plant used to treat diabetes in traditional medicine. In mammals, benzylamine is metabolized by semicarbazide-sensitive amine oxidase (SSAO) to benzaldehyde and hydrogen peroxide. This latter product has insulin-mimicking action, and is involved in the effects of benzylamine on human adipocytes: stimulation of glucose transport and inhibition of lipolysis. This study examined whether chronic, oral administration of benzylamine could improve glucose tolerance and the circulating lipid profile without increasing oxidative stress in overweight and pre-diabetic mice. The benzylamine diffusion across the intestine was verified using everted gut sacs. Then, glucose handling and metabolic markers were measured in mice rendered insulin-resistant when fed a high-fat diet (HFD) and receiving or not benzylamine in their drinking water (3600micromol/(kgday)) for 17 weeks. HFD-benzylamine mice showed lower body weight gain, fasting blood glucose, total plasma cholesterol and hyperglycaemic response to glucose load when compared to HFD control. In adipocytes, insulin-induced activation of glucose transport and inhibition of lipolysis remained unchanged. In aorta, benzylamine treatment partially restored the nitrite levels that were reduced by HFD. In liver, lipid peroxidation markers were reduced. Resistin and uric acid, surrogate plasma markers of metabolic syndrome, were decreased. In spite of the putative deleterious nature of the hydrogen peroxide generated during amine oxidation, and in agreement with its in vitro insulin-like actions found on adipocytes, the SSAO-substrate benzylamine could be considered as a potential oral agent to treat metabolic syndrome. Copyright 2010 Elsevier Ltd. All rights reserved.

Helichrysum and Grapefruit Extracts Boost Weight Loss in Overweight Rats Reducing Inflammation.

PubMed

de la Garza, Ana Laura; Etxeberria, Usune; Haslberger, Alexander; Aumueller, Eva; Martínez, J Alfredo; Milagro, Fermín I

2015-08-01

Obesity is characterized by an increased production of inflammatory markers. High levels of circulating free fatty acids and chronic inflammation lead to increased oxidative stress, contributing to the development of insulin resistance (IR). Recent studies have focused on the potential use of flavonoids for obesity management due to their antioxidant and anti-inflammatory properties. This study was designed to investigate the antioxidant and anti-inflammatory effects of helichrysum and grapefruit extracts in overweight insulin-resistant rats. Thirty-eight male Wistar rats were randomly distributed in two groups: control group (n=8) and high-fat sucrose (HFS) group (n=30). After 22 days of ad libitum water and food access, the rats fed HFS diet changed to standard diet and were reassigned into three groups (n=10 each group): nonsupplemented, helichrysum extract (2 g/kg bw), and grapefruit extract (1 g/kg bw) administered for 5 weeks. Rats supplemented with both extracts gained less body weight during the 5-week period of treatment, showed lower serum insulin levels and liver TBARS levels. Leptin/adiponectin ratio, as an indicator of IR, was lower in both extract-administered groups. These results were accompanied by a reduction in TNFα gene expression in epididymal adipose tissue and intestinal mucosa, and TLR2 expression in intestinal mucosa. Helichrysum and grapefruit extracts might be used as complement hypocaloric diets in weight loss treatment. Both extracts helped to reduce weight gain, hyperinsulinemia, and IR, improved inflammation markers, and decreased the HFS diet-induced oxidative stress in insulin-resistant rats.

Characterization of the Prediabetic State in a Novel Rat Model of Type 2 Diabetes, the ZFDM Rat.

PubMed

Gheni, Ghupurjan; Yokoi, Norihide; Beppu, Masayuki; Yamaguchi, Takuro; Hidaka, Shihomi; Kawabata, Ayako; Hoshino, Yoshikazu; Hoshino, Masayuki; Seino, Susumu

2015-01-01

We recently established a novel animal model of obese type 2 diabetes (T2D), the Zucker fatty diabetes mellitus (ZFDM) rat strain harboring the fatty mutation (fa) in the leptin receptor gene. Here we performed a phenotypic characterization of the strain, focusing mainly on the prediabetic state. At 6-8 weeks of age, fa/fa male rats exhibited mild glucose intolerance and severe insulin resistance. Although basal insulin secretion was remarkably high in the isolated pancreatic islets, the responses to both glucose stimulation and the incretin GLP-1 were retained. At 10-12 weeks of age, fa/fa male rats exhibited marked glucose intolerance as well as severe insulin resistance similar to that at the earlier age. In the pancreatic islets, the insulin secretory response to glucose stimulation was maintained but the response to the incretin was diminished. In nondiabetic Zucker fatty (ZF) rats, the insulin secretory responses to both glucose stimulation and the incretin in the pancreatic islets were similar to those of ZFDM rats. As islet architecture was destroyed with age in ZFDM rats, a combination of severe insulin resistance, diminished insulin secretory response to incretin, and intrinsic fragility of the islets may cause the development of T2D in this strain.

Insulin-stimulated Na/sup +/ transport in a model renal epithelium: protein synthesis dependence and receptor interactions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blazer-Yost, B.L.; Cox, M.

1987-05-01

The urinary bladder of the toad, Bufo marinus, is a well characterized model of the mammalian distal nephron. Porcine insulin (approx. 0.5-5.0 ..mu..M) stimulates net mucosal to serosal Na/sup +/ flux within 10 minutes of hormone addition. The response is maintained for at least 5 hr and is completely abolished by low doses (10..mu..M) of the epithelial Na/sup +/ channel blocker amiloride. Insulin-stimulated Na/sup +/ transport does not require new protein synthesis since it is actinomycin-D (10..mu..g/ml) insensitive. Also in 3 separate experiments in which epithelial cell proteins were examined by /sup 35/S-methionine labeling, 2-dimensional polyacrylamide gel electrophoresis/autoradiography, no insulinmore » induced proteins were observed. Equimolar concentrations of purified porcine proinsulin and insulin (0.64..mu..M) stimulate Na/sup +/ transport to the same extent. Thus, the putative toad insulin receptor may have different affinity characteristics than those demonstrated for insulin and proinsulin in mammalian tissues. Alternatively, the natriferic action of insulin in toad urinary bladders may be mediated by occupancy of another receptor. Preliminary experiments indicating that nanomolar concentrations of IGF/sub 1/ stimulate Na/sup +/ transport in this tissue support the latter contention.« less

PATHOPHYSIOLOGY AND TREATMENT OF TYPE 2 DIABETES: PERSPECTIVES ON THE PAST, PRESENT AND FUTURE

PubMed Central

Kahn, Steven E.; Cooper, Mark E.; Del Prato, Stefano

2014-01-01

Normal regulation of glucose metabolism is determined by a feedback loop involving the islet β-cell and insulin-sensitive tissues in which tissue sensitivity to insulin determines the magnitude of the β-cell response. When insulin resistance is present, the β-cell maintains normal glucose tolerance by increasing insulin output. It is only when the β-cell is incapable of releasing sufficient insulin in the presence of insulin resistance that glucose levels rise. While β-cell dysfunction has a clear genetic component, environmental changes play a vital role. Modern approaches have also informed regarding the importance of hexoses, amino acids and fatty acids in determining insulin resistance and β-cell dysfunction as well as the potential role of alterations in the microbiome. A number of new treatment approaches have been developed, but more effective therapies that slow the progressive loss of β-cell function are needed. Recent clinical trials have provided important information regarding approaches to prevent and treat type 2 diabetes as well as some of the adverse effects of these interventions. However, additional long-term studies of medications and bariatric surgery are required in order to identify novel approaches to prevention and treatment, thereby reducing the deleterious impact of type 2 diabetes. PMID:24315620

Insulin activates single amiloride-blockable Na channels in a distal nephron cell line (A6).

PubMed

Marunaka, Y; Hagiwara, N; Tohda, H

1992-09-01

Using the patch-clamp technique, we studied the effect of insulin on an amiloride-blockable Na channel in the apical membrane of a distal nephron cell line (A6) cultured on permeable collagen films for 10-14 days. NPo (N, number of channels per patch membrane; Po, average value of open probability of individual channels in the patch) under baseline conditions was 0.88 +/- 0.12 (SE)(n = 17). After making cell-attached patches on the apical membrane which contained Na channels, insulin (1 mU/ml) was applied to the serosal bath. While maintaining the cell-attached patch, NPo significantly increased to 1.48 +/- 0.19 (n = 17; P less than 0.001) after 5-10 min of insulin application. The open probability of Na channels was 0.39 +/- 0.01 (n = 38) under baseline condition, and increased to 0.66 +/- 0.03 (n = 38, P less than 0.001) after addition of insulin. The baseline single-channel conductance was 4pS, and neither the single-channel conductance nor the current-voltage relationship was significantly changed by insulin. These results indicate that insulin increases Na absorption in the distal nephron by increasing the open probability of the amiloride-blockable Na channel.

Effect of gonadectomy on AgRP-induced weight gain in rats.

PubMed

Goodin, Sean Z; Kiechler, Alicia R; Keichler, Alicia R; Smith, Marissa; Wendt, Donna; Strader, April D

2008-12-01

Agouti-related peptide (AgRP), the endogenous antagonist to the melanocortin 3 and 4 receptors, elicits robust hyperphagia and weight gain in rodents when administered directly into the central nervous system. The relative influence of AgRP to cause weight gain in rodents partially depends on the activity level of the melanocortin agonist-producing proopiomelanocortin neurons. Both proopiomelanocortin and AgRP neurons within the arcuate nucleus receive energy storage information from circulating peripheral signals such as leptin and insulin. Another modulator of AgRP activity includes the cell surface molecule syndecan-3. Because leptin and insulin affect food intake in a sexually dimorphic way in rodents and syndecan-3-deficient mice regulate adiposity levels through distinct physiological mechanisms, we hypothesized that AgRP-induced weight gain would also be sexually dimorphic in rats. In the present study, the behavioral and physiological effects of centrally-administered AgRP in male and female were investigated. In male rats, AgRP (1 nmol) induced 5 days (P < 0.0001) of significantly elevated feeding compared with vehicle-treated controls, while females displayed 3 days of hyperphagia (P < 0.05). However, 1 wk after the injection, both male and female rats gained the same percent body weight (6%). Interestingly, female rats exhibited a greater reduction in energy expenditure (Vo2) following AgRP compared with male rats (P < 0.05). Removal of the gonads did not alter cumulative food intake in male or female rats but did attenuate the dramatic reduction in Vo2 exhibited by females. Both intact and gonadectomized rats demonstrated significantly increased respiratory quotient supporting the anabolic action of AgRP (P < 0.01). These findings are novel in that they reveal sex-specific underlying physiology used to achieve weight gain following central AgRP in rats.

Linear Growth and Fat and Lean Tissue Gain during Childhood: Associations with Cardiometabolic and Cognitive Outcomes in Adolescent Indian Children.

PubMed

Krishnaveni, Ghattu V; Veena, Sargoor R; Srinivasan, Krishnamachari; Osmond, Clive; Fall, Caroline H D

2015-01-01

We aimed to determine how linear growth and fat and lean tissue gain during discrete age periods from birth to adolescence are related to adolescent cardiometabolic risk factors and cognitive ability. Adolescents born to mothers with normal glucose tolerance during pregnancy from an Indian birth cohort (N = 486, age 13.5 years) had detailed anthropometry and measurements of body fat (fat%), fasting plasma glucose, insulin and lipid concentrations, blood pressure and cognitive function. Insulin resistance (HOMA-IR) was calculated. These outcomes were examined in relation to birth measurements and statistically independent measures (conditional SD scores) representing linear growth, and fat and lean tissue gain during birth-1, 1-2, 2-5, 5-9.5 and 9.5-13.5 years in 414 of the children with measurements at all these ages. Birth length and linear growth at all ages were positively associated with current height. Fat gain, particularly during 5-9.5 years was positively associated with fat% at 13.5 years (0.44 SD per SD [99.9% confidence interval: 0.29,0.58]). Greater fat gain during mid-late childhood was associated with higher systolic blood pressure (5-9.5 years: 0.23 SD per SD [0.07,0.40]) and HOMA-IR (5-9.5 years: 0.24 [0.08,0.40], 9.5-13.5 years: 0.22 [0.06,0.38]). Greater infant growth (up to age 2 years) in linear, fat or lean components was unrelated to cardiometabolic risk factors or cognitive function. This study suggests that factors that increase linear, fat and lean growth in infancy have no adverse cardiometabolic effects in this population. Factors that increase fat gain in mid-late childhood may increase cardiometabolic risk, without any benefit to cognitive abilities.

Randomized Controlled Trial of a MUFA or Fiber-Rich Diet on Hepatic Fat in Prediabetes

PubMed Central

Errazuriz, Isabel; Dube, Simmi; Slama, Michael; Visentin, Roberto; Nayar, Sunita; O’Connor, Helen; Cobelli, Claudio; Das, Swapan Kumar; Basu, Ananda; Kremers, Walter Karl; Port, John

2017-01-01

Context: Increased prevalence of type 2 diabetes mellitus and prediabetes worldwide is attributed in part to an unhealthy diet. Objective: To evaluate whether 12 weeks of high monounsaturated fatty acid (MUFA) or fiber-rich weight-maintenance diet lowers hepatic fat and improves glucose tolerance in people with prediabetes. Design: Subjects underwent a [6, 6-2H2]–labeled 75-g oral glucose tolerance test to estimate hepatic insulin sensitivity and liver fat fraction (LFF) using magnetic resonance spectroscopy before and after intervention. Setting: Mayo Clinic Clinical Research Trials Unit. Participants: 43 subjects with prediabetes. Intervention: Subjects were randomized into three isocaloric weight-maintaining diets containing MUFA (olive oil), extra fiber, and standard US food (control-habitual diet). Outcome Measures: LFF, glucose tolerance, and indices of insulin action and secretion. Results: Body weight was maintained constant in all groups during the intervention. Glucose and hormonal concentrations were similar in all groups before, and unchanged after, 12 weeks of intervention. LFF was significantly lower after intervention in the MUFA group (P < 0.0003) but remained unchanged in the fiber (P = 0.25) and control groups (P = 0.45). After 12 weeks, LFF was significantly lower in the MUFA than in the control group (P = 0.01), but fiber and control groups did not differ (P = 0.41). Indices of insulin action and secretion were not significantly different between the MUFA and control groups after intervention (P ≥ 0.11), but within-group comparison showed higher hepatic (P = 0.01) and total insulin sensitivity (P < 0.04) with MUFA. Conclusions: Twelve weeks of a MUFA diet decreases hepatic fat and improves both hepatic and total insulin sensitivity. PMID:28323952

Reduced Socs3 expression in adipose tissue protects female mice against obesity-induced insulin resistance.

PubMed

Palanivel, R; Fullerton, M D; Galic, S; Honeyman, J; Hewitt, K A; Jorgensen, S B; Steinberg, G R

2012-11-01

Inflammation in obesity increases the levels of the suppressor of cytokine signalling-3 (SOCS3) protein in adipose tissue, but the physiological importance of this protein in regulating whole-body insulin sensitivity in obesity is not known. We generated Socs3 floxed (wild-type, WT) and Socs3 aP2 (also known as Fabp4)-Cre null (Socs3 AKO) mice. Mice were maintained on either a regular chow or a high-fat diet (HFD) for 16 weeks during which time body mass, adiposity, glucose homeostasis and insulin sensitivity were assessed. The HFD increased SOCS3 levels in adipose tissue of WT but not Socs3 AKO mice. WT and Socs3 AKO mice had similar body mass and adiposity, assessed using computed tomography (CT) imaging, irrespective of diet or sex. On a control chow diet there were no differences in insulin sensitivity or glucose tolerance. When fed a HFD, female but not male Socs3 AKO mice had improved glucose tolerance as well as lower fasting glucose and insulin levels compared with WT littermates. Hyperinsulinaemic-euglycaemic clamps and positron emission tomography (PET) imaging demonstrated that improved insulin sensitivity was due to elevated adipose tissue glucose uptake. Increased insulin-stimulated glucose uptake in adipose tissue was associated with enhanced levels and activating phosphorylation of insulin receptor substrate-1 (IRS1). These data demonstrate that inhibiting SOCS3 production in adipose tissue of female mice is effective for improving whole-body insulin sensitivity in obesity.

Decaffeinated Green Coffee Bean Extract Attenuates Diet-Induced Obesity and Insulin Resistance in Mice

PubMed Central

Song, Su Jin; Choi, Sena; Park, Taesun

2014-01-01

This study investigated whether decaffeinated green coffee bean extract prevents obesity and improves insulin resistance and elucidated its mechanism of action. Male C57BL/6N mice (N = 48) were divided into six dietary groups: chow diet, HFD, HFD-supplemented with 0.1%, 0.3%, and 0.9% decaffeinated green coffee bean extract, and 0.15% 5-caffeoylquinic acid. Based on the reduction in HFD-induced body weight gain and increments in plasma lipids, glucose, and insulin levels, the minimum effective dose of green coffee bean extract appears to be 0.3%. Green coffee bean extract resulted in downregulation of genes involved in WNT10b- and galanin-mediated adipogenesis and TLR4-mediated proinflammatory pathway and stimulation of GLUT4 translocation to the plasma membrane in white adipose tissue. Taken together, decaffeinated green coffee bean extract appeared to reverse HFD-induced fat accumulation and insulin resistance by downregulating the genes involved in adipogenesis and inflammation in visceral adipose tissue. PMID:24817902

Leptin and insulin pathways in POMC and AgRP neurons that modulate energy balance and glucose homeostasis.

PubMed

Varela, Luis; Horvath, Tamas L

2012-12-01

With the steady rise in the prevalence of obesity and its associated diseases, research aimed at understanding the mechanisms that regulate and control whole body energy homeostasis has gained new interest. Leptin and insulin, two anorectic hormones, have key roles in the regulation of body weight and energy homeostasis, as highlighted by the fact that several obese patients develop resistance to these hormones. Within the brain, the hypothalamic proopiomelanocortin and agouti-related protein neurons have been identified as major targets of leptin and insulin action. Many studies have attempted to discern the individual contributions of various components of the principal pathways that mediate the central effects of leptin and insulin. The aim of this review is to discuss the latest findings that might shed light on, and lead to a better understanding of, energy balance and glucose homeostasis. In addition, recently discovered targets and mechanisms that mediate hormonal action in the brain are highlighted.

Leptin and insulin pathways in POMC and AgRP neurons that modulate energy balance and glucose homeostasis

PubMed Central

Varela, Luis; Horvath, Tamas L

2012-01-01

With the steady rise in the prevalence of obesity and its associated diseases, research aimed at understanding the mechanisms that regulate and control whole body energy homeostasis has gained new interest. Leptin and insulin, two anorectic hormones, have key roles in the regulation of body weight and energy homeostasis, as highlighted by the fact that several obese patients develop resistance to these hormones. Within the brain, the hypothalamic proopiomelanocortin and agouti-related protein neurons have been identified as major targets of leptin and insulin action. Many studies have attempted to discern the individual contributions of various components of the principal pathways that mediate the central effects of leptin and insulin. The aim of this review is to discuss the latest findings that might shed light on, and lead to a better understanding of, energy balance and glucose homeostasis. In addition, recently discovered targets and mechanisms that mediate hormonal action in the brain are highlighted. PMID:23146889

Keeping Up with the Diabetes Technology: 2016 Endocrine Society Guidelines of Insulin Pump Therapy and Continuous Glucose Monitor Management of Diabetes.

PubMed

Galderisi, Alfonso; Schlissel, Elise; Cengiz, Eda

2017-09-23

Decades after the invention of insulin pump, diabetes management has encountered a technology revolution with the introduction of continuous glucose monitoring, sensor-augmented insulin pump therapy and closed-loop/artificial pancreas systems. In this review, we discuss the significance of the 2016 Endocrine Society Guidelines for insulin pump therapy and continuous glucose monitoring and summarize findings from relevant diabetes technology studies that were conducted after the publication of the 2016 Endocrine Society Guidelines. The 2016 Endocrine Society Guidelines have been a great resource for clinicians managing diabetes in this new era of diabetes technology. There is good body of evidence indicating that using diabetes technology systems safely tightens glycemic control while managing both type 1 and type 2 diabetes. The first-generation diabetes technology systems will evolve as we gain more experience and collaboratively work to improve them with an ultimate goal of keeping people with diabetes complication and burden-free until the cure for diabetes becomes a reality.

Jatropha curcas Protein Concentrate Stimulates Insulin Signaling, Lipogenesis, Protein Synthesis and the PKCα Pathway in Rat Liver.

PubMed

León-López, Liliana; Márquez-Mota, Claudia C; Velázquez-Villegas, Laura A; Gálvez-Mariscal, Amanda; Arrieta-Báez, Daniel; Dávila-Ortiz, Gloria; Tovar, Armando R; Torres, Nimbe

2015-09-01

Jatropha curcas is an oil seed plant that belongs to the Euphorbiaceae family. Nontoxic genotypes have been reported in Mexico. The purpose of the present work was to evaluate the effect of a Mexican variety of J. curcas protein concentrate (JCP) on weight gain, biochemical parameters, and the expression of genes and proteins involved in insulin signaling, lipogenesis, cholesterol and protein synthesis in rats. The results demonstrated that short-term consumption of JCP increased serum glucose, insulin, triglycerides and cholesterol levels as well as the expression of transcription factors involved in lipogenesis and cholesterol synthesis (SREBP-1 and LXRα). Moreover, there was an increase in insulin signaling mediated by Akt phosphorylation and mTOR. JCP also increased PKCα protein abundance and the activation of downstream signaling pathway targets such as the AP1 and NF-κB transcription factors typically activated by phorbol esters. These results suggested that phorbol esters are present in JCP, and that they could be involved in the activation of PKC which may be responsible for the high insulin secretion and consequently the activation of insulin-dependent pathways. Our data suggest that this Mexican Jatropha variety contains toxic compounds that produce negative metabolic effects which require caution when using in the applications of Jatropha-based products in medicine and nutrition.

Differential Effects of High-Carbohydrate and High-Fat Diet Composition on Metabolic Control and Insulin Resistance in Normal Rats

PubMed Central

Ble-Castillo, Jorge L.; Aparicio-Trapala, María A.; Juárez-Rojop, Isela E.; Torres-Lopez, Jorge E.; Mendez, Jose D.; Aguilar-Mariscal, Hidemi; Olvera-Hernández, Viridiana; Palma-Cordova, Leydi C.; Diaz-Zagoya, Juan C.

2012-01-01

The macronutrient component of diets is critical for metabolic control and insulin action. The aim of this study was to compare the effects of high fat diets (HFDs) vs. high carbohydrate diets (HCDs) on metabolic control and insulin resistance in Wistar rats. Thirty animals divided into five groups (n = 6) were fed: (1) Control diet (CD); (2) High-saturated fat diet (HSFD); (3) High-unsaturated fat diet (HUFD); (4) High-digestible starch diet, (HDSD); and (5) High-resistant starch diet (HRSD) during eight weeks. HFDs and HCDs reduced weight gain in comparison with CD, however no statistical significance was reached. Calorie intake was similar in both HFDs and CD, but rats receiving HCDs showed higher calorie consumption than other groups, (p < 0.01). HRSD showed the lowest levels of serum and hepatic lipids. The HUFD induced the lowest fasting glycemia levels and HOMA-IR values. The HDSD group exhibited the highest insulin resistance and hepatic cholesterol content. In conclusion, HUFD exhibited the most beneficial effects on glycemic control meanwhile HRSD induced the highest reduction on lipid content and did not modify insulin sensitivity. In both groups, HFDs and HCDs, the diet constituents were more important factors than caloric intake for metabolic disturbance and insulin resistance. PMID:22754464

Atypical antipsychotics and glucose homeostasis.

PubMed

Bergman, Richard N; Ader, Marilyn

2005-04-01

Persistent reports have linked atypical antipsychotics with diabetes, yet causative mechanisms responsible for this linkage are unclear. Goals of this review are to outline the pathogenesis of nonimmune diabetes and to survey the available literature related to why antipsychotics may lead to this disease. We accessed the literature regarding atypical antipsychotics and glucose homeostasis using PubMed. The search included English-language publications from 1990 through October 2004. Keywords used included atypical antipsychotics plus one of the following: glucose, insulin, glucose tolerance, obesity, or diabetes. In addition, we culled information from published abstracts from several national and international scientific meetings for the years 2001 through 2004, including the American Diabetes Association, the International Congress on Schizophrenia Research, and the American College of Neuropsychopharmacology. The latter search was necessary because of the paucity of well-controlled prospective studies. We examined publications with significant new data or publications that contributed to the overall comprehension of the impact of atypical antipsychotics on glucose metabolism. We favored original peer-reviewed articles and were less likely to cite single case studies and/or anecdotal information. Approximately 75% of the fewer than 150 identified articles were examined and included in this review. Validity of data was evaluated using the existence of peer-review status as well as our own experience with methodology described in the specific articles. The metabolic profile caused by atypical antipsychotic treatment resembles type 2 diabetes. These agents cause weight gain in treated subjects and may induce obesity in both visceral and subcutaneous depots, as occurs in diabetes. Insulin resistance, usually associated with obesity, occurs to varying degrees with different antipsychotics, although more comparative studies with direct assessment of resistance are needed. A major problem in assessing drug effects is that psychiatric disease itself can cause many of the manifestations leading to diabetes, including weight gain and sedentary lifestyle. While studies in healthy subjects are limited and inconclusive, studies in animal models are more revealing. In the conscious canine model, some atypical antipsychotics cause adiposity, including visceral obesity, a strong risk factor for the metabolic syndrome. Furthermore, while few studies have examined effects of antipsychotics on pancreatic beta-cell function, canine studies demonstrate that expected beta-cell compensation for insulin resistance may be reduced or even eliminated with these agents. Atypical antipsychotics have been shown to contribute to weight gain, which may well reflect increased body fat deposition. Such increased fat is known to cause resistance to insulin action, although more information regarding effect on insulin action is needed. The effect of these drugs on fat distribution has been clearly shown in animal models. It is known that the normal response to insulin resistance is compensatory hyperinsulinemia, which may prevent diabetes. In animals, there is evidence that the hyperinsulinemic compensation is inadequate in the face of atypical antipsychotic agents. It remains to be examined whether failure of adequate pancreatic beta-cell compensation for insulin resistance plays a central role in the pathogenesis of diabetes associated with this class of drugs.

The 'skinny' on childhood obesity: how our western environment starves kids' brains.

PubMed

Lustig, Robert H

2006-12-01

In this review, the mechanism of our "toxic environment's" effects on insulin and weight gain in the genesis of obesity is elaborated. The composition of our diet is highly insulinogenic. The insulin drives energy into fat, and interferes with leptin signaling in the VMH. This results in weight gain and the sense of starvation, which results in decreased SNS activity, reducing energy expenditure and physical activity; and increased vagal activity, which promotes yet further insulin release and energy storage. Thus, hyperinsulinemia turns the leptin negative feedback system into a "vicious cycle" of obesity (see Figure 3, page 905). Externally, this appears as "gluttony and sloth" but it is biochemically driven. How does this work? A thin, insulin-sensitive, 13-year-old boy might consume a daily allotment of 2,000 kcal, and burn 2,000 kcal daily (or 50 kcal/kg fat-free mass) in order to remain weight-stable, with a stable leptin level. However, if that same 13-year-old became hyperinsulinemic and/or insulin resistant, perhaps as many as 250 kcal of the daily allotment would be shunted to storage in adipose tissue, promoting a persistent obligate weight gain. Due to the obligate energy storage, he now only has 1,750 kcal per day to burn. The hyperinsulinemia also results in a lower level of leptin signal transduction, conveying a CNS signal of energy insufficiency. The remaining calories available are lower than his energy expenditure; the CNS would sense starvation. Through decreased SNS tone, he would reduce his physical activity, resulting in decreased quality of life; and through increased vagal tone, he would increase caloric intake and insulin secretion, but now at a much higher level. Thus, the vicious cycle of gluttony, sloth, and obesity is promulgated. Is this personal responsibility, when a kid's brain thinks it's starving? Is it personal responsibility when the American Academy of Pediatrics still recommends juice for toddlers? Is it personal responsibility when the Women, Infant and Children program subsidizes fruit juice but not fruit? Is it personal responsibility when the first ingredient in the barbecue sauce is high-fructose corn syrup? Is it personal responsibility when high-fiber fresh produce is unavailable in poor neighborhoods? Is it personal responsibility when the local fast food restaurant is the only neighborhood venue that is clean and air-conditioned? Is it personal responsibility when in order to meet the criteria for No Child Left Behind, the school does away with physical education class? Is it personal responsibility when children are not allowed out of the house to play for fear of crime? We must get the insulin down. Fixing the "toxic environment" by altering the food supply and promoting physical activity for all children can't be done by government, and won't be done by Big Food. This will require a grassroots, bottom-up effort on the part of parents and community leaders. We as pediatricians must lead the way.

Favourable metabolic effects of a eucaloric lower-carbohydrate diet in women with PCOS.

PubMed

Gower, Barbara A; Chandler-Laney, Paula C; Ovalle, Fernando; Goree, Laura Lee; Azziz, Ricardo; Desmond, Renee A; Granger, Wesley M; Goss, Amy M; Bates, G Wright

2013-10-01

Diet-induced reduction in circulating insulin may be an attractive nonpharmacological treatment for women with polycystic ovary syndrome (PCOS) among whom elevated insulin may exacerbate symptoms by stimulating testosterone synthesis. This study was designed to determine whether a modest reduction in dietary carbohydrate (CHO) content affects β-cell responsiveness, serum testosterone concentration and insulin sensitivity in women with PCOS. In a crossover design, two diets ('Standard,' STD, 55:18:27% energy from carbohydrate/protein/fat; lower-carbohydrate, 41:19:40) were provided for 8 weeks in random order with a 4-week washout between. Thirty women with PCOS. β-cell responsiveness assessed as the C-peptide response to glucose during a liquid meal test; insulin sensitivity from insulin and glucose values throughout the test; insulin resistance (HOMA-IR); and total testosterone by immunoassay. Paired t-test indicated that the lower-CHO diet induced significant decreases in basal β-cell response (PhiB), fasting insulin, fasting glucose, HOMA-IR, total testosterone and all cholesterol measures, and significant increases in insulin sensitivity and dynamic ('first-phase') β-cell response. The STD diet induced a decrease in HDL-C and an increase in the total cholesterol-to-HDL-C ratio. Across all data combined, the change in testosterone was positively associated with the changes in fasting insulin, PhiB and insulin AUC (P < 0·05). In women with PCOS, modest reduction in dietary CHO in the context of a weight-maintaining diet has numerous beneficial effects on the metabolic profile that may lead to a decrease in circulating testosterone. © 2013 John Wiley & Sons Ltd.

Butyrate Improves Insulin Sensitivity and Increases Energy Expenditure in Mice

PubMed Central

Gao, Zhanguo; Yin, Jun; Zhang, Jin; Ward, Robert E.; Martin, Roy J.; Lefevre, Michael; Cefalu, William T.; Ye, Jianping

2009-01-01

OBJECTIVE We examined the role of butyric acid, a short-chain fatty acid formed by fermentation in the large intestine, in the regulation of insulin sensitivity in mice fed a high-fat diet. RESEARCH DESIGN AND METHODS In dietary-obese C57BL/6J mice, sodium butyrate was administrated through diet supplementation at 5% wt/wt in the high-fat diet. Insulin sensitivity was examined with insulin tolerance testing and homeostasis model assessment for insulin resistance. Energy metabolism was monitored in a metabolic chamber. Mitochondrial function was investigated in brown adipocytes and skeletal muscle in the mice. RESULTS On the high-fat diet, supplementation of butyrate prevented development of insulin resistance and obesity in C57BL/6 mice. Fasting blood glucose, fasting insulin, and insulin tolerance were all preserved in the treated mice. Body fat content was maintained at 10% without a reduction in food intake. Adaptive thermogenesis and fatty acid oxidation were enhanced. An increase in mitochondrial function and biogenesis was observed in skeletal muscle and brown fat. The type I fiber was enriched in skeletal muscle. Peroxisome proliferator–activated receptor-γ coactivator-1α expression was elevated at mRNA and protein levels. AMP kinase and p38 activities were elevated. In the obese mice, supplementation of butyrate led to an increase in insulin sensitivity and a reduction in adiposity. CONCLUSIONS Dietary supplementation of butyrate can prevent and treat diet-induced insulin resistance in mouse. The mechanism of butyrate action is related to promotion of energy expenditure and induction of mitochondria function. PMID:19366864

Combined treatment with melatonin and insulin improves glycemic control, white adipose tissue metabolism and reproductive axis of diabetic male rats.

PubMed

Oliveira, Ariclecio Cunha de; Andreotti, Sandra; Sertie, Rogério António Laurato; Campana, Amanda Baron; de Proença, André Ricardo Gomes; Vasconcelos, Renata Prado; Oliveira, Keciany Alves de; Coelho-de-Souza, Andrelina Noronha; Donato-Junior, José; Lima, Fábio Bessa

2018-04-15

Melatonin treatment has been reported to be capable of ameliorating metabolic diabetes-related abnormalities but also to cause hypogonadism in rats. We investigated whether the combined treatment with melatonin and insulin can improve insulin resistance and other metabolic disorders in rats with streptozotocin-induced diabetes during neonatal period and the repercussion of this treatment on the hypothalamic-pituitary-gonadal axis. At the fourth week of age, diabetic animals started an 8-wk treatment with only melatonin (0.2 mg/kg body weight) added to drinking water at night or associated with insulin (NHP, 1.5 U/100 g/day) or only insulin. Animals were then euthanized, and the subcutaneous (SC), epididymal (EP), and retroperitoneal (RP) fat pads were excised, weighed and processed for adipocyte isolation for morphometric analysis as well as for measuring glucose uptake, oxidation, and incorporation of glucose into lipids. Hypothalamus was collected for gene expression and blood samples were collected for biochemical assays. The treatment with melatonin plus insulin (MI) was capable of maintaining glycemic control. In epididymal (EP) and subcutaneous (SC) adipocytes, the melatonin plus insulin (MI) treatment group recovered the insulin responsiveness. In the hypothalamus, melatonin treatment alone promoted a significant reduction in kisspeptin-1, neurokinin B and androgen receptor mRNA levels, in relation to control group. Combined treatment with melatonin and insulin promoted a better glycemic control, improving insulin sensitivity in white adipose tissue (WAT). Indeed, melatonin treatment reduced hypothalamic genes related to reproductive function. Copyright © 2017. Published by Elsevier Inc.

Characteristics Predictive for a Successful Switch from Insulin Analogue Therapy to Oral Hypoglycemic Agents in Patients with Type 2 Diabetes

PubMed Central

Kim, Gyuri; Lee, Yong-ho; Kang, Eun Seok; Cha, Bong-Soo; Lee, Hyun Chul

2016-01-01

Purpose The objective of this study was to investigate clinical and laboratory parameters that could predict which patients could maintain adequate glycemic control after switching from initial insulin therapy to oral hypoglycemic agents (OHAs) among patients with type 2 diabetes (T2D). Materials and Methods We recruited 275 patients with T2D who had been registered in 3 cohorts of initiated insulin therapy and followed up for 33 months. The participants were divided into 2 groups according to whether they switched from insulin to OHAs (Group I) or not (Group II), and Group I was further classified into 2 sub-groups: maintenance on OHAs (Group IA) or resumption of insulin (Group IB). Results Of 275 patients with insulin initiation, 63% switched to OHAs (Group I) and 37% continued insulin (Group II). Of these, 44% were in Group IA and 19% in Group IB. The lowest tertile of baseline postprandial C-peptide-to-glucose ratio (PCGR), higher insulin dose at switching to OHAs, and higher HbA1c level at 6 months after switching to OHAs were all associated with OHA failure (Group IB; p=0.001, 0.046, and 0.014, respectively). The lowest tertile of PCGR was associated with ultimate use of insulin (Group IB and Group II; p=0.029). Conclusion Higher baseline level of PCGR and lower HbA1c levels at 6 months after switching to OHAs may be strong predictors for the successful maintenance of OHAs after switching from insulin therapy in Korean patients with T2D. PMID:27593867

Hepatic F-Box Protein FBXW7 Maintains Glucose Homeostasis Through Degradation of Fetuin-A.

PubMed

Zhao, Jiejie; Xiong, Xuelian; Li, Yao; Liu, Xing; Wang, Tao; Zhang, Hong; Jiao, Yang; Jiang, Jingjing; Zhang, Huijie; Tang, Qiqun; Gao, Xin; Li, Xuejun; Lu, Yan; Liu, Bin; Hu, Cheng; Li, Xiaoying

2018-05-01

Type 2 diabetes mellitus (T2DM) has become one of the most serious and long-term threats to human health. However, the molecular mechanism that links obesity to insulin resistance remains largely unknown. Here, we show that F-box and WD repeat domain-containing 7 (FBXW7), an E3 ubiquitin protein ligase, is markedly downregulated in the liver of two obese mouse models and obese human subjects. We further identify a functional low-frequency human FBXW7 coding variant (p.Ala204Thr) in the Chinese population, which is associated with elevated blood glucose and T2DM risk. Notably, mice with liver-specific knockout of FBXW7 develop hyperglycemia, glucose intolerance, and insulin resistance even on a normal chow diet. Conversely, overexpression of FBXW7 in the liver not only prevents the development of high-fat diet-induced insulin resistance but also attenuates the disease signature of obese mice. Mechanistically, FBXW7 directly binds to hepatokine fetuin-A to induce its ubiquitination and subsequent proteasomal degradation, comprising an important mechanism maintaining glucose homeostasis. Thus, we provide evidence showing a beneficial role of FBXW7 in glucose homeostasis. © 2018 by the American Diabetes Association.

Pancreas allograft biopsies in the management of pancreas transplant recipients: histopathologic review and clinical correlations.

PubMed

Gaber, Lillian W

2007-08-01

Pancreas transplantation has become a therapeutic option for patients with type 1 diabetes mellitus who are in end-stage renal failure. It also is indicated for a subset of nonuremic, insulin-dependent diabetics who experience extreme difficulties in maintaining proper glucose homeostasis by insulin therapy that compromises their productivity and safety. To provide a review of the literature and expert experiences for understanding the histologic findings in pancreas transplantation. The published literature between 1990 and 2005 was reviewed for this report. Additionally, personal files of the author were used, along with biopsy slides that were used for figures. Pancreas transplantation reestablishes the physiologic state of insulin secretion, and pancreas transplant recipients are able to maintain a state of long-term euglycemia and are less likely to be exposed to hyperglycemia and its systemic complications. Key to the success of transplantation is the scrupulous management and close monitoring of the pancreas transplant recipients. To that end, histologic evaluation of pancreas allografts assumed a pivotal role in management of pancreas allograft dysfunction episodes, and in some centers surveillance biopsies are used to monitor immunologically high-risk situations.

Remission in models of type 1 diabetes by gene therapy using a single-chain insulin analogue

NASA Astrophysics Data System (ADS)

Lee, Hyun Chul; Kim, Su-Jin; Kim, Kyung-Sup; Shin, Hang-Cheol; Yoon, Ji-Won

2000-11-01

A cure for diabetes has long been sought using several different approaches, including islet transplantation, regeneration of β cells and insulin gene therapy. However, permanent remission of type 1 diabetes has not yet been satisfactorily achieved. The development of type 1 diabetes results from the almost total destruction of insulin-producing pancreatic β cells by autoimmune responses specific to β cells. Standard insulin therapy may not maintain blood glucose concentrations within the relatively narrow range that occurs in the presence of normal pancreatic β cells. We used a recombinant adeno-associated virus (rAAV) that expresses a single-chain insulin analogue (SIA), which possesses biologically active insulin activity without enzymatic conversion, under the control of hepatocyte-specific L-type pyruvate kinase (LPK) promoter, which regulates SIA expression in response to blood glucose levels. Here we show that SIA produced from the gene construct rAAV-LPK-SIA caused remission of diabetes in streptozotocin-induced diabetic rats and autoimmune diabetic mice for a prolonged time without any apparent side effects. This new SIA gene therapy may have potential therapeutic value for the cure of autoimmune diabetes in humans.

Real-world clinical responses in patients with type 2 diabetes mellitus adding exenatide BID (EBID) or mealtime insulin to basal insulin: a retrospective study using electronic medical record data.

PubMed

Lang, Kathleen; Nguyen, Hiep; Huang, Huan; Bauer, Elise; Levin, Philip

2018-06-01

Exenatide twice daily (EBID) and mealtime insulin are effective add-on therapies to basal insulin for type 2 diabetes patients in clinical trials. This study used electronic medical record (EMR) data to evaluate analogous real-world clinical responses. Adult patients initiating EBID or mealtime insulin as add-on to basal insulin during January 2008-March 2013 were identified in a US EMR database. EBID patients were propensity score matched 1:1 to mealtime insulin patients. Cohorts were followed for 12 months before (baseline) and 6 months after the index. A1C, hypoglycemic events, change in weight, and other clinical measures were evaluated by A1C attainment level (<6.5, < 7, < 7.5, <8, <9%) and baseline A1C. In total, 1249 EBID patients were matched to 1249 mealtime insulin patients. During follow-up, the percentage reaching A1C levels was similar for EBID vs mealtime insulin cohorts for all attainment levels (<7%: 27.8% vs 24.2%; < 9%: 79.7% vs 79.2%; p = NS). The percentage reaching A1C < 7% was similar for both cohorts with different baseline A1C. EBID patients had less hypoglycemia at all attainment levels (3.1% vs 11.1% [<6.5%]; 2.5% vs 4.7% [<9%]; all p < .03) and more weight loss (-9.0 vs -3.2 lb [<6.5%]; -3.4 vs +0.8 lb [<9%]; all p < .01). EBID added to basal insulin was as effective in a real-world setting as mealtime insulin added to basal insulin in reducing A1C, with less weight gain and less hypoglycemia for a wide range of A1C attainment levels and baseline values.

Kir6.2 Variant E23K Increases ATP-Sensitive K+ Channel Activity and Is Associated With Impaired Insulin Release and Enhanced Insulin Sensitivity in Adults With Normal Glucose Tolerance

PubMed Central

Villareal, Dennis T.; Koster, Joseph C.; Robertson, Heather; Akrouh, Alejandro; Miyake, Kazuaki; Bell, Graeme I.; Patterson, Bruce W.; Nichols, Colin G.; Polonsky, Kenneth S.

2009-01-01

OBJECTIVE The E23K variant in the Kir6.2 subunit of the ATP-sensitive K+ channel (KATP channel) is associated with increased risk of type 2 diabetes. The present study was undertaken to increase our understanding of the mechanisms responsible. To avoid confounding effects of hyperglycemia, insulin secretion and action were studied in subjects with the variant who had normal glucose tolerance. RESEARCH DESIGN AND METHODS Nine subjects with the E23K genotype K/K and nine matched subjects with the E/E genotype underwent 5-h oral glucose tolerance tests (OGTTs), graded glucose infusion, and hyperinsulinemic-euglycemic clamp with stable-isotope–labeled tracer infusions to assess insulin secretion, action, and clearance. A total of 461 volunteers consecutively genotyped for the E23K variant also underwent OGTTs. Functional studies of the wild-type and E23K variant potassium channels were conducted. RESULTS Insulin secretory responses to oral and intravenous glucose were reduced by ∼40% in glucose-tolerant subjects homozygous for E23K. Normal glucose tolerance with reduced insulin secretion suggests a change in insulin sensitivity. The hyperinsulinemic-euglycemic clamp revealed that hepatic insulin sensitivity is ∼40% greater in subjects with the E23K variant, and these subjects demonstrate increased insulin sensitivity after oral glucose. The reconstituted E23K channels confirm reduced sensitivity to inhibitory ATP and increase in open probability, a direct molecular explanation for reduced insulin secretion. CONCLUSIONS The E23K variant leads to overactivity of the KATP channel, resulting in reduced insulin secretion. Initially, insulin sensitivity is enhanced, thereby maintaining normal glucose tolerance. Presumably, over time, as insulin secretion falls further or insulin resistance develops, glucose levels rise resulting in type 2 diabetes. PMID:19491206

Free Fatty Acid-Induced PP2A Hyperactivity Selectively Impairs Hepatic Insulin Action on Glucose Metabolism

PubMed Central

Galbo, Thomas; Olsen, Grith Skytte; Quistorff, Bjørn; Nishimura, Erica

2011-01-01

In type 2 Diabetes (T2D) free fatty acids (FFAs) in plasma are increased and hepatic insulin resistance is “selective”, in the sense that the insulin-mediated decrease of glucose production is blunted while insulin's effect on stimulating lipogenesis is maintained. We investigated the molecular mechanisms underlying this pathogenic paradox. Primary rat hepatocytes were exposed to palmitate for twenty hours. To establish the physiological relevance of the in vitro findings, we also studied insulin-resistant Zucker Diabetic Fatty (ZDF) rats. While insulin-receptor phosphorylation was unaffected, activation of Akt and inactivation of the downstream targets Glycogen synthase kinase 3α (Gsk3α and Forkhead box O1 (FoxO1) was inhibited in palmitate-exposed cells. Accordingly, dose-response curves for insulin-mediated suppression of the FoxO1-induced gluconeogenic genes and for de novo glucose production were right shifted, and insulin-stimulated glucose oxidation and glycogen synthesis were impaired. In contrast, similar to findings in human T2D, the ability of insulin to induce triglyceride (TG) accumulation and transcription of the enzymes that catalyze de novo lipogenesis and TG assembly was unaffected. Insulin-induction of these genes could, however, be blocked by inhibition of the atypical PKCs (aPKCs). The activity of the Akt-inactivating Protein Phosphatase 2A (PP2A) was increased in the insulin-resistant cells. Furthermore, inhibition of PP2A by specific inhibitors increased insulin-stimulated activation of Akt and phosphorylation of FoxO1 and Gsk3α. Finally, PP2A mRNA levels were increased in liver, muscle and adipose tissue, while PP2A activity was increased in liver and muscle tissue in insulin-resistant ZDF rats. In conclusion, our findings indicate that FFAs may cause a selective impairment of insulin action upon hepatic glucose metabolism by increasing PP2A activity. PMID:22087313

The transcription factor Prep1 controls hepatic insulin sensitivity and gluconeogenesis by targeting nuclear localization of FOXO1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kulebyakin, Konstantin; Penkov, Dmitry; IFOM – the FIRC Institute of Molecular Oncology, Via Adamello 16, Milan, 20139

Liver plays a key role in controlling body carbohydrate homeostasis by switching between accumulation and production of glucose and this way maintaining constant level of glucose in blood. Increased blood glucose level triggers release of insulin from pancreatic β-cells. Insulin represses hepatic glucose production and increases glucose accumulation. Insulin resistance is the main cause of type 2 diabetes and hyperglycemia. Currently thiazolidinediones (TZDs) targeting transcriptional factor PPARγ are used as insulin sensitizers for treating patients with type 2 diabetes. However, TZDs are reported to be associated with cardiovascular and liver problems and stimulate obesity. Thus, it is necessary to searchmore » new approaches to improve insulin sensitivity. A promising candidate is transcriptional factor Prep1, as it was shown earlier it could affect insulin sensitivity in variety of insulin-sensitive tissues. The aim of the present study was to evaluate a possible involvement of transcriptional factor Prep1 in control of hepatic glucose accumulation and production. We created mice with liver-specific Prep1 knockout and discovered that hepatocytes derived from these mice are much more sensitive to insulin, comparing to their WT littermates. Incubation of these cells with 100 nM insulin results in almost complete inhibition of gluconeogenesis, while in WT cells this repression is only partial. However, Prep1 doesn't affect gluconeogenesis in the absence of insulin. Also, we observed that nuclear content of gluconeogenic transcription factor FOXO1 was greatly reduced in Prep1 knockout hepatocytes. These findings suggest that Prep1 may control hepatic insulin sensitivity by targeting FOXO1 nuclear stability. - Highlights: • A novel model of liver-specific Prep1 knockout is established. • Ablation of Prep1 in hepatocytes increases insulin sensitivity. • Prep1 controls hepatic insulin sensitivity by regulating localization of FOXO1. • Prep1 regulates localization of FOXO1 via Wnt/β-catenin signaling pathway.« less

Patient-level meta-analysis of the EDITION 1, 2 and 3 studies: glycaemic control and hypoglycaemia with new insulin glargine 300 U/ml versus glargine 100 U/ml in people with type 2 diabetes.

PubMed

Ritzel, R; Roussel, R; Bolli, G B; Vinet, L; Brulle-Wohlhueter, C; Glezer, S; Yki-Järvinen, H

2015-09-01

To conduct a patient-level meta-analysis of the EDITION 1, 2 and 3 studies, which compared the efficacy and safety of new insulin glargine 300 U/ml (Gla-300) with insulin glargine 100 U/ml (Gla-100) in people with type 2 diabetes (T2DM) on basal and mealtime insulin, basal insulin and oral antihyperglycaemic drugs, or no prior insulin, respectively. The EDITION studies were multicentre, randomized, open-label, parallel-group, phase IIIa studies, with similar designs and endpoints. A patient-level meta-analysis of the studies enabled these endpoints to be examined over 6 months in a large population with T2DM (Gla-300, n = 1247; Gla-100, n = 1249). No significant study-by-treatment interactions across studies were found, enabling them to be pooled. The mean change in glycated haemoglobin was comparable for Gla-300 and Gla-100 [each -1.02 (standard error 0.03)%; least squares (LS) mean difference 0.00 (95% confidence interval (CI) -0.08 to 0.07)%]. Annualized rates of confirmed (≤3.9 mmol/l) or severe hypoglycaemia were lower with Gla-300 than with Gla-100 during the night (31% difference in rate ratio over 6 months) and at any time (24 h, 14% difference). Consistent reductions were observed in percentage of participants with ≥1 hypoglycaemic event. Severe hypoglycaemia at any time (24 h) was rare (Gla-300: 2.3%; Gla-100: 2.6%). Weight gain was low (<1 kg) in both groups, with less gain with Gla-300 [LS mean difference -0.28 kg (95% CI -0.55 to -0.01); p = 0.039]. Both treatments were well tolerated, with similar rates of adverse events. Gla-300 provides comparable glycaemic control to Gla-100 in a large population with a broad clinical spectrum of T2DM, with consistently less hypoglycaemia at any time of day and less nocturnal hypoglycaemia. © 2015 The Authors. Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.

A Patient-level Analysis of Efficacy and Hypoglycaemia Outcomes Across Treat-to-target Trials with Insulin Glargine Added to Oral Antidiabetes Agents in People with Type 2 Diabetes

PubMed Central

DeVries, J Hans; Meneghini, Luigi; Barnett, Anthony H; Reid, Timothy; Dain, Marie-Paule; Vlajnic, Aleksandra; Traylor, Louise; Bergenstal, Richard M

2014-01-01

Abstract Background: A better understanding of hypoglycaemia risk when insulin is used in combination with one or more oral antidiabetes agents may assist in the treatment decision-making process for the clinician and address concerns regarding hypoglycaemia when initiating or intensifying insulin therapy. The objective of this study was to analyse efficacy and hypoglycaemia outcomes in people with type 2 diabetes receiving insulin glargine (IG) with metformin (MET), sulphonylurea (SU) or MET+SU. Methods: Patient-level data were pooled from 15 randomised, treat-to-target trials (fasting plasma glucose [FPG] targets <5.6 mmol/l) with a duration >24 weeks. Efficacy outcomes included glycated haemoglobin (HbA1c), FPG and HbA1c target achievement. Overall hypoglycaemia events were assessed by a confirmed PG value of <3.9, <3.1 and <2.8 mmol/l or assistance required; daytime, nocturnal (00:01-05:59 AM); and severe (assistance required or with confirmed PG <2.0 mmol/l). Results: Overall, 2,837 IG patients were analysed, with either MET (634), SU (906) or MET+SU (1,297) as background oral antidiabetes agents. Endpoint HbA1c in IG+MET and IG+MET+SU-treated patients was significantly lower than in IG+SU-treated patients (adjusted difference -0.32 %; p=0.0001 and -0.33 %; p=0.0002, respectively). Fewer patients achieved endpoint HbA1c <7.0 % with IG+SU (32 %) versus IG+MET (57 %) or IG+MET+SU (49 %). IG+SU and IG+MET+SU led to significant increases in overall, daytime and nocturnal hypoglycaemia versus IG+MET; severe hypoglycaemia was rare. Weight gain was lowest in IG+MET patients (adjusted difference -1.51 kg versus IG+SU; p<0.0001; -0.78 kg versus IG+MET+SU; p=0.0037) despite higher insulin doses (0.51 U/kg versus 0.43 and 0.42 U/kg, respectively). Conclusions: Better glycaemic goal achievement and reduced risk of hypoglycaemia and weight gain were observed with IG+MET versus IG+SU and IG+MET+SU, albeit with an increased insulin dose requirement. PMID:29872460

Metformin in women with type 2 diabetes in pregnancy (MiTy): a multi-center randomized controlled trial.

PubMed

Feig, Denice S; Murphy, Kellie; Asztalos, Elizabeth; Tomlinson, George; Sanchez, Johanna; Zinman, Bernard; Ohlsson, Arne; Ryan, Edmond A; Fantus, I George; Armson, Anthony B; Lipscombe, Lorraine L; Barrett, Jon F R

2016-07-19

The incidence of type 2 diabetes in pregnancy is rising and rates of serious adverse maternal and fetal outcomes remain high. Metformin is a biguanide that is used as first-line treatment for non-pregnant patients with type 2 diabetes. We hypothesize that metformin use in pregnancy, as an adjunct to insulin, will decrease adverse outcomes by reducing maternal hyperglycemia, maternal insulin doses, maternal weight gain and gestational hypertension/pre-eclampsia. In addition, since metformin crosses the placenta, metformin treatment of the fetus may have a direct beneficial effect on neonatal outcomes. Our aim is to compare the effectiveness of the addition of metformin to insulin, to standard care (insulin plus placebo) in women with type 2 diabetes in pregnancy. The MiTy trial is a multi-centre randomized trial currently enrolling pregnant women with type 2 diabetes, who are on insulin, between the ages of 18-45, with a gestational age of 6 weeks 0 days to 22 weeks 6 days. In this randomized, double-masked, parallel placebo-controlled trial, after giving informed consent, women are randomized to receive either metformin 1,000 mg twice daily or placebo twice daily. A web-based block randomization system is used to assign women to metformin or placebo in a 1:1 ratio, stratified for site and body mass index. The primary outcome is a composite neonatal outcome of pregnancy loss, preterm birth, birth injury, moderate/severe respiratory distress, neonatal hypoglycemia, or neonatal intensive care unit admission longer than 24 h. Secondary outcomes are large for gestational age, cord blood gas pH < 7.0, congenital anomalies, hyperbilirubinemia, sepsis, hyperinsulinemia, shoulder dystocia, fetal fat mass, as well as maternal outcomes: maternal weight gain, maternal insulin doses, maternal glycemic control, maternal hypoglycemia, gestational hypertension, preeclampsia, cesarean section, number of hospitalizations during pregnancy, and duration of hospital stays. The trial aims to enroll 500 participants. The results of this trial will inform endocrinologists, obstetricians, family doctors, and other healthcare professionals caring for women with type 2 diabetes in pregnancy, as to the benefits of adding metformin to insulin in this high risk population. ClinicalTrials.gov Identifier: no. NCT01353391 . Registered February 6, 2009.

Initiation of Basal Insulin Analog Treatment for Type 2 Diabetes and Reasons Behind Patients' Treatment Persistence Behavior: Real-World Data from Germany.

PubMed

Moennig, Elisabeth; Perez-Nieves, Magaly; Hadjiyianni, Irene; Cao, Dachuang; Ivanova, Jasmina; Klask, Ralf

2018-05-01

Poor treatment persistence can affect the real-world effectiveness of insulin therapy. A cross-sectional online survey in 942 patients with type 2 diabetes from 7 different countries evaluated patient experience when initiating basal insulin and the reasons behind insulin persistence patterns. Here, we report the quantitative results for the subset of patients from Germany. Adults with type 2 diabetes who had initiated basal insulin during the last 3-24 months, identified from market-research panels, participated in the survey. Patients were asked if they had ≥7-day gaps in basal insulin treatment, and were then classified as "continuers" (no gap since starting insulin), "interrupters" (≥1 gap within the first 6 months after starting insulin and subsequently restarted insulin), or "discontinuers" (stopped insulin within the first 6 months after starting and had not restarted at the time of the survey). For each country, 50 participants were planned per persistence category. Enrollment ended if the target quota was reached or enrollment plateaued. Data were analyzed overall and separately for each persistence cohort. The 131 participants from Germany included 55 (42.0%) continuers, 50 (38.2%) interrupters and 26 (19.9%) discontinuers. The most common motivations to initiate basal insulin therapy were encouragement by physician or other healthcare provider (HCP; 54.2%) and expectation to improve glycemic control (42.0%). More than 95% of participants received training before and during insulin initiation (considered as helpful by 81.7%); most (67.2%) preferred in-person training. Continuers more frequently felt that insulin would help to manage diabetes and that their own views were considered when initiating insulin, they reported less concerns and challenges before and during insulin initiation than interrupters or discontinuers. The most common motivations to continue basal insulin were improved glycemic control (72.7%), improved physical well-being (49.1%), and instruction by physician or other HCP (45.5%). The most common reasons contributing to interruption/discontinuation were perceived weight gain (52.0%/50.0%), hypoglycemia (22.0%/38.5%), and potential adverse effects (30.0%/26.9%). Quality interactions between physicians or other HCPs and their patients before and during the initiation of basal insulin may help to manage patient expectations and to improve persistence to insulin therapy. © Georg Thieme Verlag KG Stuttgart · New York.

Prolonged Fasting Identifies Skeletal Muscle Mitochondrial Dysfunction as Consequence Rather Than Cause of Human Insulin Resistance

PubMed Central

Hoeks, Joris; van Herpen, Noud A.; Mensink, Marco; Moonen-Kornips, Esther; van Beurden, Denis; Hesselink, Matthijs K.C.; Schrauwen, Patrick

2010-01-01

OBJECTIVE Type 2 diabetes and insulin resistance have been associated with mitochondrial dysfunction, but it is debated whether this is a primary factor in the pathogenesis of the disease. To test the concept that mitochondrial dysfunction is secondary to the development of insulin resistance, we employed the unique model of prolonged fasting in humans. Prolonged fasting is a physiologic condition in which muscular insulin resistance develops in the presence of increased free fatty acid (FFA) levels, increased fat oxidation and low glucose and insulin levels. It is therefore anticipated that skeletal muscle mitochondrial function is maintained to accommodate increased fat oxidation unless factors secondary to insulin resistance exert negative effects on mitochondrial function. RESEARCH DESIGN AND METHODS While in a respiration chamber, twelve healthy males were subjected to a 60 h fast and a 60 h normal fed condition in a randomized crossover design. Afterward, insulin sensitivity was assessed using a hyperinsulinemic-euglycemic clamp, and mitochondrial function was quantified ex vivo in permeabilized muscle fibers using high-resolution respirometry. RESULTS Indeed, FFA levels were increased approximately ninefold after 60 h of fasting in healthy male subjects, leading to elevated intramuscular lipid levels and decreased muscular insulin sensitivity. Despite an increase in whole-body fat oxidation, we observed an overall reduction in both coupled state 3 respiration and maximally uncoupled respiration in permeabilized skeletal muscle fibers, which could not be explained by changes in mitochondrial density. CONCLUSIONS These findings confirm that the insulin-resistant state has secondary negative effects on mitochondrial function. Given the low insulin and glucose levels after prolonged fasting, hyperglycemia and insulin action per se can be excluded as underlying mechanisms, pointing toward elevated plasma FFA and/or intramuscular fat accumulation as possible causes for the observed reduction in mitochondrial capacity. PMID:20573749

Bioactives in blueberries improve insulin sensitivity in obese, insulin-resistant men and women.

PubMed

Stull, April J; Cash, Katherine C; Johnson, William D; Champagne, Catherine M; Cefalu, William T

2010-10-01

Dietary supplementation with whole blueberries in a preclinical study resulted in a reduction in glucose concentrations over time. We sought to evaluate the effect of daily dietary supplementation with bioactives from blueberries on whole-body insulin sensitivity in men and women. A double-blinded, randomized, and placebo-controlled clinical study design was used. After screening to resolve study eligibility, baseline (wk 0) insulin sensitivity was measured on 32 obese, nondiabetic, and insulin-resistant subjects using a high-dose hyperinsulinemic-euglycemic clamp (insulin infusion of 120 mU(861 pmol)⋅m(-2)⋅min(-1)). Serum inflammatory biomarkers and adiposity were measured at baseline. At the end of the study, insulin sensitivity, inflammatory biomarkers, and adiposity were reassessed. Participants were randomized to consume either a smoothie containing 22.5 g blueberry bioactives (blueberry group, n = 15) or a smoothie of equal nutritional value without added blueberry bioactives (placebo group, n = 17) twice daily for 6 wk. Both groups were instructed to maintain their body weight by reducing ad libitum intake by an amount equal to the energy intake of the smoothies. Participants' body weights were evaluated weekly and 3-d food records were collected at baseline, the middle, and end of the study. The mean change in insulin sensitivity improved more in the blueberry group (1.7 ± 0.5 mg⋅kg FFM(-1)⋅min(-1)) than in the placebo group (0.4 ± 0.4 mg⋅kg FFM(-1)⋅min(-1)) (P = 0.04). Insulin sensitivity was enhanced in the blueberry group at the end of the study without significant changes in adiposity, energy intake, and inflammatory biomarkers. In conclusion, daily dietary supplementation with bioactives from whole blueberries improved insulin sensitivity in obese, nondiabetic, and insulin-resistant participants.

Bioactives in Blueberries Improve Insulin Sensitivity in Obese, Insulin-Resistant Men and Women1234

PubMed Central

Stull, April J.; Cash, Katherine C.; Johnson, William D.; Champagne, Catherine M.; Cefalu, William T.

2010-01-01

Dietary supplementation with whole blueberries in a preclinical study resulted in a reduction in glucose concentrations over time. We sought to evaluate the effect of daily dietary supplementation with bioactives from blueberries on whole-body insulin sensitivity in men and women. A double-blinded, randomized, and placebo-controlled clinical study design was used. After screening to resolve study eligibility, baseline (wk 0) insulin sensitivity was measured on 32 obese, nondiabetic, and insulin-resistant subjects using a high-dose hyperinsulinemic-euglycemic clamp (insulin infusion of 120 mU(861 pmol)⋅m−2⋅min−1). Serum inflammatory biomarkers and adiposity were measured at baseline. At the end of the study, insulin sensitivity, inflammatory biomarkers, and adiposity were reassessed. Participants were randomized to consume either a smoothie containing 22.5 g blueberry bioactives (blueberry group, n = 15) or a smoothie of equal nutritional value without added blueberry bioactives (placebo group, n = 17) twice daily for 6 wk. Both groups were instructed to maintain their body weight by reducing ad libitum intake by an amount equal to the energy intake of the smoothies. Participants’ body weights were evaluated weekly and 3-d food records were collected at baseline, the middle, and end of the study. The mean change in insulin sensitivity improved more in the blueberry group (1.7 ± 0.5 mg⋅kg FFM−1⋅min−1) than in the placebo group (0.4 ± 0.4 mg⋅kg FFM−1⋅min−1) (P = 0.04). Insulin sensitivity was enhanced in the blueberry group at the end of the study without significant changes in adiposity, energy intake, and inflammatory biomarkers. In conclusion, daily dietary supplementation with bioactives from whole blueberries improved insulin sensitivity in obese, nondiabetic, and insulin-resistant participants. PMID:20724487

Release of skeletal muscle peptide fragments identifies individual proteins degraded during insulin deprivation in type 1 diabetic humans and mice.

PubMed

Robinson, Matthew M; Dasari, Surendra; Karakelides, Helen; Bergen, H Robert; Nair, K Sreekumaran

2016-09-01

Insulin regulates skeletal muscle protein degradation, but the types of proteins being degraded in vivo remain to be determined due to methodological limitations. We present a method to assess the types of skeletal muscle proteins that are degraded by extracting their degradation products as low-molecular weight (LMW) peptides from muscle samples. High-resolution mass spectrometry was used to identify the original intact proteins that generated the LMW peptides, which we validated in rodents and then applied to humans. We deprived insulin from insulin-treated streptozotocin (STZ) diabetic mice for 6 and 96 h and for 8 h in type 1 diabetic humans (T1D) for comparison with insulin-treated conditions. Protein degradation was measured using activation of autophagy and proteasome pathways, stable isotope tracers, and LMW approaches. In mice, insulin deprivation activated proteasome pathways and autophagy in muscle homogenates and isolated mitochondria. Reproducibility analysis of LMW extracts revealed that ∼80% of proteins were detected consistently. As expected, insulin deprivation increased whole body protein turnover in T1D. Individual protein degradation increased with insulin deprivation, including those involved in mitochondrial function, proteome homeostasis, nDNA support, and contractile/cytoskeleton. Individual mitochondrial proteins that generated more LMW fragment with insulin deprivation included ATP synthase subunit-γ (+0.5-fold, P = 0.007) and cytochrome c oxidase subunit 6 (+0.305-fold, P = 0.03). In conclusion, identifying LMW peptide fragments offers an approach to determine the degradation of individual proteins. Insulin deprivation increases degradation of select proteins and provides insight into the regulatory role of insulin in maintaining proteome homeostasis, especially of mitochondria. Copyright © 2016 the American Physiological Society.

Lipid and insulin infusion-induced skeletal muscle insulin resistance is likely due to metabolic feedback and not changes in IRS-1, Akt, or AS160 phosphorylation.

PubMed

Hoy, Andrew J; Brandon, Amanda E; Turner, Nigel; Watt, Matthew J; Bruce, Clinton R; Cooney, Gregory J; Kraegen, Edward W

2009-07-01

Type 2 diabetes is characterized by hyperlipidemia, hyperinsulinemia, and insulin resistance. The aim of this study was to investigate whether acute hyperlipidemia-induced insulin resistance in the presence of hyperinsulinemia was due to defective insulin signaling. Hyperinsulinemia (approximately 300 mU/l) with hyperlipidemia or glycerol (control) was produced in cannulated male Wistar rats for 0.5, 1 h, 3 h, or 5 h. The glucose infusion rate required to maintain euglycemia was significantly reduced by 3 h with lipid infusion and was further reduced after 5 h of infusion, with no difference in plasma insulin levels, indicating development of insulin resistance. Consistent with this finding, in vivo skeletal muscle glucose uptake (31%, P < 0.05) and glycogen synthesis rate (38%, P < 0.02) were significantly reduced after 5 h compared with 3 h of lipid infusion. Despite the development of insulin resistance, there was no difference in the phosphorylation state of multiple insulin-signaling intermediates or muscle diacylglyceride and ceramide content over the same time course. However, there was an increase in cumulative exposure to long-chain acyl-CoA (70%) with lipid infusion. Interestingly, although muscle pyruvate dehydrogenase kinase 4 protein content was decreased in hyperinsulinemic glycerol-infused rats, this decrease was blunted in muscle from hyperinsulinemic lipid-infused rats. Decreased pyruvate dehydrogenase complex activity was also observed in lipid- and insulin-infused animals (43%). Overall, these results suggest that acute reductions in muscle glucose metabolism in rats with hyperlipidemia and hyperinsulinemia are more likely a result of substrate competition than a significant early defect in insulin action or signaling.

Release of skeletal muscle peptide fragments identifies individual proteins degraded during insulin deprivation in type 1 diabetic humans and mice

PubMed Central

Robinson, Matthew M.; Dasari, Surendra; Karakelides, Helen; Bergen, H. Robert

2016-01-01

Insulin regulates skeletal muscle protein degradation, but the types of proteins being degraded in vivo remain to be determined due to methodological limitations. We present a method to assess the types of skeletal muscle proteins that are degraded by extracting their degradation products as low-molecular weight (LMW) peptides from muscle samples. High-resolution mass spectrometry was used to identify the original intact proteins that generated the LMW peptides, which we validated in rodents and then applied to humans. We deprived insulin from insulin-treated streptozotocin (STZ) diabetic mice for 6 and 96 h and for 8 h in type 1 diabetic humans (T1D) for comparison with insulin-treated conditions. Protein degradation was measured using activation of autophagy and proteasome pathways, stable isotope tracers, and LMW approaches. In mice, insulin deprivation activated proteasome pathways and autophagy in muscle homogenates and isolated mitochondria. Reproducibility analysis of LMW extracts revealed that ∼80% of proteins were detected consistently. As expected, insulin deprivation increased whole body protein turnover in T1D. Individual protein degradation increased with insulin deprivation, including those involved in mitochondrial function, proteome homeostasis, nDNA support, and contractile/cytoskeleton. Individual mitochondrial proteins that generated more LMW fragment with insulin deprivation included ATP synthase subunit-γ (+0.5-fold, P = 0.007) and cytochrome c oxidase subunit 6 (+0.305-fold, P = 0.03). In conclusion, identifying LMW peptide fragments offers an approach to determine the degradation of individual proteins. Insulin deprivation increases degradation of select proteins and provides insight into the regulatory role of insulin in maintaining proteome homeostasis, especially of mitochondria. PMID:27436610

Fasting serum insulin and the homeostasis model of insulin resistance (HOMA-IR) in the monitoring of lifestyle interventions in obese persons.

PubMed

Vogeser, Michael; König, Daniel; Frey, Ingrid; Predel, Hans-Georg; Parhofer, Klaus Georg; Berg, Aloys

2007-09-01

Lifestyle changes with increased physical activity and balanced energy intake are recognized as the principal interventions in obesity and insulin resistance. Only few prospective studies, however, have so far addressed the potential role of routine biochemical markers of insulin sensitivity in the monitoring of respective interventions. Fasting insulin and glucose was measured in 33 obese individuals undergoing a lifestyle modification program (MOBILIS) at baseline and after 1 year. The HOMA-IR index (homeostasis model of insulin resistance) was calculated as [fasting serum glucose*fasting serum insulin/22.5], with lower values indicating a higher degree of insulin sensitivity. While the median body mass index (BMI) and waist circumference decreased by 10% and 11%, respectively, the HOMA-IR index decreased in an over-proportional manner by 45% within 1 year (BMI baseline, median 35.7, interquartile range (IQR) 33.7-37.7; after 1 year, median 32.2, IQR 29.6-35.1. HOMA-IR baseline, median 2.9, IQR 1.5-4.6; after 1 year 1.6, IQR 0.9-2.7). In contrast to HOMA-IR and fasting serum insulin, no significant changes in fasting serum glucose were observed. Baseline and post-intervention HOMA-IR showed a high degree of inter-individual variation with eight individuals maintaining high HOMA-IR values despite weight loss after 1 year of intervention. Individual changes in the carbohydrate metabolism achieved by a lifestyle intervention program were displayed by fasting serum insulin concentrations and the HOMA-IR but not by fasting glucose measurement alone. Therefore, assessment of the HOMA-IR may help to individualize lifestyle interventions in obesity and to objectify improvements in insulin sensitivity after therapeutic lifestyle changes.

Differential effects of high-fat diets varying in fatty acid composition on the efficiency of lean and fat tissue deposition during weight recovery after low food intake.

PubMed

Dulloo, A G; Mensi, N; Seydoux, J; Girardier, L

1995-02-01

The energetics of body weight recovery after low food intake was examined in the rat during refeeding for 2 weeks with isocaloric amounts of high-fat (HF) diets providing 50% of energy as either lard, coconut oil, olive oil, safflower oil, menhaden fish oil, or a mixture of all these fat types. The results indicate that for both body fat and protein, the efficiency of deposition was dependent on the dietary fat type. The most striking differences were found (1) between diets rich in n-3 and n-6 polyunsaturated fatty acids (PUFA), with the diet high in fish oil resulting in a greater body fat deposition and lower protein gain than the diet high in safflower oil; and (2) between diets rich in long-chain (LCT) and medium-chain triglycerides (MCT), with the diet high in lard resulting in a greater gain in both body fat and protein than the diet high in coconut oil. Furthermore, the diet high in olive oil (a monounsaturated fat) and the mixed-fat diet (containing all fat types) were found to be similar to the fish oil diet in that the efficiency of fat deposition was greater (and that of protein gain lower) than with the diet high in safflower oil. Neither the efficiency of fat gain nor that of protein gain were found to correlate with fasting plasma insulin, the insulin to glucose ratio, or plasma lipids.(ABSTRACT TRUNCATED AT 250 WORDS)

Donohue syndrome and use of continuous subcutaneous insulin pump therapy.

PubMed

Huggard, Dean; Stack, Tom; Satas, Saulius; Gorman, Clodagh O

2015-10-27

Donohue syndrome is a rare autosomal recessive condition caused by severe loss-of-function mutations in the insulin receptor (INSR) gene. The diagnosis is made on clinical, biochemical and genetic grounds. Mutations are found on chromosome 19p13.2, and code for mutations in the INSR gene. Treatment is challenging and often unsuccessful, and relies on maintaining normoglycaemia and avoiding fasting; in some patients, recombinant human insulin-like growth factor (rhIGF-1) has been trialled. The prognosis is poor, with most babies dying in infancy. Ethically, it is important to consider the benefit versus burden of treatment, the quality of life of the surviving patient and the parents' wishes, when making decisions regarding withholding or withdrawing care. 2015 BMJ Publishing Group Ltd.

Mango leaf extract improves central pathology and cognitive impairment in a type 2 diabetes mouse model.

PubMed

Infante-Garcia, Carmen; Jose Ramos-Rodriguez, Juan; Marin-Zambrana, Yolanda; Teresa Fernandez-Ponce, Maria; Casas, Lourdes; Mantell, Casimiro; Garcia-Alloza, Monica

2017-07-01

Epidemiological studies reveal that metabolic disorders, and specifically type 2 diabetes (T2D), are relevant risk factors to develop Alzheimer's disease (AD) and vascular dementia (VaD), the most common causes of dementia. AD patients are in a tremendous need of new therapeutic options because of the limited success of available treatments. Natural polyphenols, and concretely Mangifera indica Linn extract (MGF), have been reported to have antiinflammatory, antioxidant and antidiabetic activities. The role of MGF in central complications associated with T2D, after long-term treatment of db/db mice with MGF was analyzed. Metabolic parameters (body weight, glucose and insulin levels) as well as central complications including brain atrophy, inflammatory processes, spontaneous bleeding, tau phosphorylation and cognitive function in db/db mice treated with MGF for 22 weeks were assessed. MGF limits body weight gain in obese db/db mice. Insulin and C-peptide levels, indicative of pancreatic function, were longer maintained in MGF-treated animals. MGF reduced central inflammation by lowering microglia burden, both in the cortex and the hippocampus. Likewise, central spontaneous bleeding was significantly reduced in db/db mice. Cortical and hippocampal atrophy was reduced in db/db mice and tau hyperphosphorylation was lower after MGF treatment, resulting in partial recovery of learning and memory disabilities. Altogether, the data suggested that MGF treatment may provide a useful tool to target different aspects of AD and VaD pathology, and could lead to more effective clinical therapies for the prevention of metabolic related central complications associated with AD and VaD. © 2016 International Society of Neuropathology.

Impact of taurine depletion on glucose control and insulin secretion in mice.

PubMed

Ito, Takashi; Yoshikawa, Natsumi; Ito, Hiromi; Schaffer, Stephen W

2015-09-01

Taurine, an endogenous sulfur-containing amino acid, is found in millimolar concentrations in mammalian tissue, and its tissue content is altered by diet, disease and aging. The effectiveness of taurine administration against obesity and its related diseases, including type 2 diabetes, has been well documented. However, the impact of taurine depletion on glucose metabolism and fat deposition has not been elucidated. In this study, we investigated the effect of taurine depletion (in the taurine transporter (TauT) knockout mouse model) on blood glucose control and high fat diet-induced obesity. TauT-knockout (TauTKO) mice exhibited lower body weight and abdominal fat mass when maintained on normal chow than wild-type (WT) mice. Blood glucose disposal after an intraperitoneal glucose injection was faster in TauTKO mice than in WT mice despite lower serum insulin levels. Islet beta-cells (insulin positive area) were also decreased in TauTKO mice compared to WT mice. Meanwhile, overnutrition by high fat (60% fat)-diet could lead to obesity in TauTKO mice despite lower body weight under normal chow diet condition, indicating nutrition in normal diet is not enough for TauTKO mice to maintain body weight comparable to WT mice. In conclusion, taurine depletion causes enhanced glucose disposal despite lowering insulin levels and lower body weight, implying deterioration in tissue energy metabolism. Copyright © 2015 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

Divergent compensatory responses to high-fat diet between C57BL6/J and C57BLKS/J inbred mouse strains.

PubMed

Sims, Emily K; Hatanaka, Masayuki; Morris, David L; Tersey, Sarah A; Kono, Tatsuyoshi; Chaudry, Zunaira Z; Day, Kathleen H; Moss, Dan R; Stull, Natalie D; Mirmira, Raghavendra G; Evans-Molina, Carmella

2013-12-01

Impaired glucose tolerance (IGT) and type 2 diabetes (T2DM) are polygenic disorders with complex pathophysiologies; recapitulating them with mouse models is challenging. Despite 70% genetic homology, C57BL/6J (BL6) and C57BLKS/J (BLKS) inbred mouse strains differ in response to diet- and genetic-induced obesity. We hypothesized these differences would yield insight into IGT and T2DM susceptibility and response to pharmacological therapies. To this end, male 8-wk-old BL6 and BLKS mice were fed normal chow (18% kcal from fat), high-fat diet (HFD; 42% kcal from fat), or HFD supplemented with the PPARγ agonist pioglitazone (PIO; 140 mg PIO/kg diet) for 16 wk. Assessments of body composition, glucose homeostasis, insulin production, and energy metabolism, as well as histological analyses of pancreata were undertaken. BL6 mice gained weight and adiposity in response to HFD, leading to peripheral insulin resistance that was met with increased β-cell proliferation and insulin production. By contrast, BLKS mice responded to HFD by restricting food intake and increasing activity. These behavioral responses limited weight gain and protected against HFD-induced glucose intolerance, which in this strain was primarily due to β-cell dysfunction. PIO treatment did not affect HFD-induced weight gain in BL6 mice, and decreased visceral fat mass, whereas in BLKS mice PIO increased total fat mass without improving visceral fat mass. Differences in these responses to HFD and effects of PIO reflect divergent human responses to a Western lifestyle and underscore the careful consideration needed when choosing mouse models of diet-induced obesity and diabetes treatment.

Reproductive performance response to the male effect in goats is improved when doe live weight/body condition score is increasing.

PubMed

Gallego-Calvo, L; Gatica, M C; Guzmán, J L; Zarazaga, L A

2015-05-01

This study examines the nutritional and metabolic cue-induced modulation of the reproductive performance response of female goats to the male effect. During natural anoestrus, 48 Blanca Andaluza does were isolated from bucks for 45 days and distributed into two groups: (1) low body weight (BW)/low body condition score (BCS) animals (LL-gain group, N=18), which were fed 1.9 times their maintenance requirements; and (2) high BW/high BCS animals (HH-loss group, N=30), which were fed 0.4 times their maintenance requirements. Following isolation, oestrous activity was recorded daily by visual observation of the marks left by harness-equipped males. Weekly blood samples were taken for the determination of progesterone, glucose, insulin, non-esterified fatty acids (NEFAs) and leptin concentrations. Fecundity, fertility, prolificacy and productivity were also determined. Significantly greater ovarian and oestrous responses, and productivity, were observed in the LL-gain group compared to the HH-loss group (P<0.05). After the introduction to the males, no differences in NEFA concentration were seen between the groups; before introduction the values were higher in the HH-loss group. At the moment of detection of oestrus following male introduction, the insulin concentration of the LL-gain animals was higher (P<0.05). The present results show that the reproductive performances of does subjected to the male effect in spring are poorer in those with a decreasing BW and BCS and better in those with increasing scores. This might be explained by the differences between groups in terms of their plasma insulin concentrations. The NEFA concentration was clearly modified by introduction to the males. Copyright © 2015 Elsevier B.V. All rights reserved.

Effects of different ratios of monounsaturated and polyunsaturated fatty acids to saturated fatty acids on regulating body fat deposition in hamsters.

PubMed

Liao, Fang-Hsuean; Liou, Tsan-Hon; Shieh, Ming-Jer; Chien, Yi-Wen

2010-01-01

Effects of monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid consumption on regulating body fat accumulation and body weight gain are controversial between animal and human studies. We designed a 2 x 2 factorial study, with two levels of MUFAs (60% and 30%) and two levels of polyunsaturated-to-saturated fatty acid (P/S) ratio (5 and 3) to prepare four kinds of experimental oils consisting of 60% MUFAs with a high or low P/S ratio (HMHR or HMLR, respectively) or 30% MUFAs with a high or low P/S ratio (LMHR or LMLR, respectively). Thirty-two male golden Syrian hamsters were randomly divided into four groups and fed the experimental diets containing 15% (w/w) fat for 12 wk. No difference was observed in the mean daily food intake. Hamsters fed the LMLR diet had increased weight gain, epididymal and retroperitoneal white adipose tissues, plasma non-esterified fatty acids, insulin, hepatic acetyl coenzyme A carboxylase and malic enzyme activities, and mRNA expressions of peroxisome proliferator-activated receptor-alpha and sterol regulatory element-binding protein-1c among all groups (P < 0.05). Hamsters fed the HMHR diet had lower plasma insulin levels and hepatic acetyl coenzyme A carboxylase activities among groups (P < 0.05) and elevated hepatic acyl coenzyme A oxidase and carnitine palmitoyltransferase-I activities compared with those fed the LMLR diet (P < 0.05). Hamsters fed the LMLR diet had increased weight gain and body fat accumulation, whereas the HMHR diet appeared to be beneficial in preventing white adipose tissue accumulation by decreasing plasma insulin levels and increasing hepatic lipolytic enzyme activities involved in beta-oxidation. 2010 Elsevier Inc. All rights reserved.

Effect of hyperglycaemia on muscarinic M3 receptor expression and secretory sensitivity to cholinergic receptor activation in islets.

PubMed

Hauge-Evans, A C; Reers, C; Kerby, A; Franklin, Z; Amisten, S; King, A J; Hassan, Z; Vilches-Flores, A; Tippu, Z; Persaud, S J; Jones, P M

2014-10-01

Islets are innervated by parasympathetic nerves which release acetylcholine (ACh) to amplify glucose-induced insulin secretion, primarily via muscarinic M3 receptors (M3R). Here we investigate the consequence of chronic hyperglycaemia on islet M3R expression and secretory sensitivity of mouse islets to cholinergic receptor activation. The impact of hyperglycaemia was studied in (i) islets isolated from ob/ob mice, (ii) alginate-encapsulated mouse islets transplanted intraperitoneally into streptozotocin-induced diabetic mice and (iii) mouse and human islets maintained in vitro at 5.5 or 16 mmol/l glucose. Blood glucose levels were assessed by a commercial glucose meter, insulin content by RIA and M3R expression by qPCR and immunohistochemistry. M3R mRNA expression was reduced in both ob/ob islets and islets maintained at 16 mmol/l glucose for 3 days (68 and 50% control, respectively). In all three models of hyperglycaemia the secretory sensitivity to the cholinergic receptor agonist, carbachol, was reduced by 60-70% compared to control islets. Treatment for 72 h with the irreversible PKC activator, PMA, or the PKC inhibitor, Gö6983, did not alter islet M3R mRNA expression nor did incubation with the PI3K-inhibitor, LY294002, although enhancement of glucose-induced insulin secretion by LY294002 was reduced in islets maintained at 16 mmol/l glucose, as was mRNA expression of the PI3K regulatory subunit, p85α. Cholinergic regulation of insulin release is impaired in three experimental islet models of hyperglycaemia consistent with reduced expression of M3 receptors. Our data suggest that the receptor downregulation is a PKC- and PI3K-independent consequence of the hyperglycaemic environment, and they imply that M3 receptors could be potential targets in the treatment of type 2 diabetes. © 2014 John Wiley & Sons Ltd.

Serum sex steroids and steroidogenesis-related enzyme expression in skeletal muscle during experimental weight gain in men.

PubMed

Sato, K; Samocha-Bonet, D; Handelsman, D J; Fujita, S; Wittert, G A; Heilbronn, L K

2014-12-01

Low-circulating testosterone is associated with development of type 2 diabetes in obese men. In this study, we examined the effects of experimental overfeeding and weight gain on serum levels of sex hormones and skeletal muscle expression of steroidogenic enzymes in healthy men with (FH+) and without (FH-) a family history of type 2 diabetes. Following a 3-day lead in energy balanced diet, FH+ (n = 9) and FH- men (n = 11) were overfed by 5200 kJ/day (45% fat) for 28 days. Body weight, fasting glucose, insulin, sex steroid, sex hormone binding globulin (SHBG) levels, insulin sensitivity (hyperinsulinaemic-euglycaemic clamp) and body fat (DXA) were assessed in all individuals at baseline and day 28, and sex steroidogenesis-related enzyme expression in vastus lateralis biopsies was examined in a subset (n = 11). Body weight, fat mass and fasting insulin levels were increased by overfeeding (P < 0.01) and insulin was increased significantly more in FH+ men (P<0.01). Serum sex hormone binding globulin (SHBG) and 5α-dihydrotestosterone (DHT) were reduced with overfeeding (P < 0.05), and serum testosterone and DHT were reduced to a greater extent in FH+ men (P < 0.05). Overfeeding reduced mRNA expression of 3β-hydroxysteroid dehydrogenase (HSD) and 17βHSD (P ≤ 0.007), independently of group. 5α-Reductase (SRD5A1) mRNA expression was not changed overall, but a time by group interaction was observed (P = 0.04). Overfeeding reduced SHBG and muscle expression of enzymes involved in the formation of testosterone in skeletal muscle. Men with a family history of T2DM were more susceptible to deleterious outcomes of overfeeding with greater reductions in serum testosterone and DHT and greater increases in markers of insulin resistance, which may contribute to increased risk of developing type 2 diabetes. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Short and long-term impact of lipectomy on expression profile of hepatic anabolic genes in rats: a high fat and high cholesterol diet-induced obese model.

PubMed

Ling, Bey-Leei; Chiu, Chun-Tang; Lu, Hsiu-Chin; Lin, Jin-Jin; Kuo, Chiung-Yin; Chou, Fen-Pi

2014-01-01

To understand the molecular basis of the short and long-term effects of an immediate shortage of energy storage caused by lipectomy on expression profile of genes involved in lipid and carbohydrate metabolism in high fat and high cholesterol diet-induced obese rats. The hepatic mRNA levels of enzymes, regulator and transcription factors involved in glucose and lipid metabolism were analyzed by quantitative real time polymerase chain reaction (RT-qPCR) ten days and eight weeks after lipectomy in obese rats. Body and liver weights and serum biochemical parameters, adiponectin, leptin and insulin were determined. No significant difference was observed on the food intake between the lipectomized and sham-operated groups during the experimental period. Ten days after the operation, the lipectomized animals showed significant higher triacylglycerol, glucose and insulin levels, a lower adiponectin concentration than the sham-operated rats, along with significant higher hepatic mRNA levels of hepatocyte nuclear factor 4α (HNF4α) and the enzymes involved in lipogenesis, sterol biosynthesis and gluconeogenesis. The results of immunohistochemical (IHC) analysis also confirmed increased levels of lipogenic enzymes in the liver of lipectomized versus sham-operated animals. The lipectomized group had a significantly lower adiponectin/leptin ratio that was positively correlated to the level of LDL (r = 0.823, P<0.05) and negatively to glucose and insulin (r = -0.821 and -0.892 respectively, P<0.05). Eight weeks after the operation, the lipectomized animals revealed significant higher body and liver weights, weight gain, liver to body weight ratio, hepatic triacylglycerol and serum insulin level. In response to lipectomy a short term enhancement of the expression of hepatic anabolic genes involved in lipid and carbohydrate metabolism was triggered that might eventually lead to the final extra weight gain. These metabolic changes could be the results of reduced circulating adiponectin that further influences the functions of insulin and hepatic HNF4α.

Regulation of the Fibrosis and Angiogenesis Promoter SPARC/Osteonectin in Human Adipose Tissue by Weight Change, Leptin, Insulin, and Glucose

PubMed Central

Kos, Katrina; Wong, Steve; Tan, Bee; Gummesson, Anders; Jernas, Margareta; Franck, Niclas; Kerrigan, David; Nystrom, Fredrik H.; Carlsson, Lena M.S.; Randeva, Harpal S.; Pinkney, Jonathan H.; Wilding, John P.H.

2009-01-01

OBJECTIVE Matricellular Secreted Protein, Acidic and Rich in Cysteine (SPARC), originally discovered in bone as osteonectin, is a mediator of collagen deposition and promotes fibrosis. Adipose tissue collagen has recently been found to be linked with metabolic dysregulation. Therefore, we tested the hypothesis that SPARC in human adipose tissue is influenced by glucose metabolism and adipokines. RESEARCH DESIGN AND METHODS Serum and adipose tissue biopsies were obtained from morbidly obese nondiabetic subjects undergoing bariatric surgery and lean control subjects for analysis of metabolic markers, SPARC, and various cytokines (RT-PCR). Additionally, 24 obese subjects underwent a very-low-calorie diet of 1,883 kJ (450 kcal)/day for 16 weeks and serial subcutaneous-abdominal-adipose tissue (SCAT) biopsies (weight loss: 28 ± 3.7 kg). Another six lean subjects underwent fast-food–based hyperalimentation for 4 weeks (weight gain: 7.2 ± 1.6 kg). Finally, visceral adipose tissue explants were cultured with recombinant leptin, insulin, and glucose, and SPARC mRNA and protein expression determined by Western blot analyses. RESULTS SPARC expression in human adipose tissue correlated with fat mass and was higher in SCAT. Weight loss induced by very-low-calorie diet lowered SPARC expression by 33% and increased by 30% in adipose tissue of subjects gaining weight after a fast-food diet. SPARC expression was correlated with leptin independent of fat mass and correlated with homeostasis model assessment–insulin resistance. In vitro experiments showed that leptin and insulin potently increased SPARC production dose dependently in visceral adipose tissue explants, while glucose decreased SPARC protein. CONCLUSIONS Our data suggest that SPARC expression is predominant in subcutaneous fat and its expression and secretion in adipose tissue are influenced by fat mass, leptin, insulin, and glucose. The profibrotic effects of SPARC may contribute to metabolic dysregulation in obesity. PMID:19509023

Glucose recruits K(ATP) channels via non-insulin-containing dense-core granules.

PubMed

Yang, Shao-Nian; Wenna, Nancy Dekki; Yu, Jia; Yang, Guang; Qiu, Hua; Yu, Lina; Juntti-Berggren, Lisa; Köhler, Martin; Berggren, Per-Olof

2007-09-01

beta cells rely on adenosine triphosphate-sensitive potassium (K(ATP)) channels to initiate and end glucose-stimulated insulin secretion through changes in membrane potential. These channels may also act as a constituent of the exocytotic machinery to mediate insulin release independent of their electrical function. However, the molecular mechanisms whereby the beta cell plasma membrane maintains an appropriate number of K(ATP) channels are not known. We now show that glucose increases K(ATP) current amplitude by increasing the number of K(ATP) channels in the beta cell plasma membrane. The effect was blocked by inhibition of protein kinase A (PKA) as well as by depletion of extracellular or intracellular Ca(2+). Furthermore, glucose promoted recruitment of the potassium inward rectifier 6.2 to the plasma membrane, and intracellular K(ATP) channels localized in chromogranin-positive/insulin-negative dense-core granules. Our data suggest that glucose can recruit K(ATP) channels to the beta cell plasma membrane via non-insulin-containing dense-core granules in a Ca(2+)- and PKA-dependent manner.

Obesity and type 1 diabetes mellitus management.

PubMed

Chillarón, J J; Benaiges, D; Mañé, L; Pedro-Botet, J; Flores Le-Roux, J A

2015-03-01

Patients with type 1 diabetes mellitus (T1DM) traditionally had a low body mass index and microangiopathic complications were common. The Diabetes Control and Complications Trial, published in 1993, demonstrated that therapy aimed at maintaining HbA1c levels as close to normal as feasible reduced the incidence of microangiopathy. Since then, the use of intensive insulin therapy to optimise metabolic control became generalised, with two main side effects: a higher rate of severe hypoglycaemia and increased weight gain. Approximately 50% of patients with T1DM are currently obese or overweight, which reduces or nullifies the benefits of good metabolic control, and which has other negative consequences; therefore, strategies to achieve weight control in patients with T1DM are necessary. At present, treatment with GLP-1 and SGLT-2 inhibitors has yielded promising short-term results that need to be confirmed in studies with larger numbers of patients and long-term follow-up. It is possible that, in coming years, the applicability of bariatric surgery in obese patients with T1DM will be similar to that of the general population or T2DM.

Reduction of abdominal fat accumulation in rats by 8-week ingestion of a newly developed sweetener made from high fructose corn syrup.

PubMed

Iida, Tetsuo; Yamada, Takako; Hayashi, Noriko; Okuma, Kazuhiro; Izumori, Ken; Ishii, Reika; Matsuo, Tatsuhiro

2013-06-01

Many studies have shown that ingestion of high-fructose corn syrup (HFCS) may cause an increase in body weight and abdominal fat. We recently developed a new sweetener containing rare sugars (rare sugar syrup; RSS) by slight isomerization of HFCS. Here, the functional effects of RSS on body weight and abdominal fat, and biochemical parameters in Wistar rats were examined. Rats (n=30) were randomly divided into three groups and maintained for 8-weeks on starch, starch+HFCS (50:50), and starch+RSS (50:50) diets. Rats in the Starch and HFCS groups gained significantly more body weight and abdominal fat than the RSS group. Fasting serum insulin in the RSS group was significantly lower than in the Starch and HFCS groups, although serum glucose in the HFCS and RSS groups was significantly lower than that in the Starch group. Thus, the substitution of HFCS with RSS prevents obesity induced by the consumption of HFCS. Copyright © 2012 Elsevier Ltd. All rights reserved.

The biology and mechanism of action of Suppressor of Cytokine Signaling 3 (SOCS3)

PubMed Central

Babon, Jeffrey; Nicola, Nicos A

2013-01-01

SOCS3 has been shown to be an important and non-redundant feedback inhibitor of several cytokines including LIF, IL-6, IL-11, CNTF, leptin and G-CSF. Loss of SOCS3 in vivo has profound effects on placental development, inflammation, fat-induced weight gain and insulin sensitivity. SOCS3 expression is induced by JAK/STAT signaling and it then binds to specific cytokine receptors (including gp130, G-CSF and leptin receptors). SOCS3 then inhibits JAK/STAT signaling in two distinct ways. First, SOCS3 is able to directly inhibit the catalytic activity of JAK1, JAK2 or TYK2 whilst remaining bound to the cytokine receptor. Second, SOCS3 recruits elongins B/C and cullin 5 to generate an E3 ligase that ubiquitinates both JAK and cytokine receptor targeting them for proteasomal degradation. Detailed in vivo studies have revealed that SOCS3 action not only limits the duration of cytokine signaling to prevent over-activity but it is also important in maintaining the specificity of cytokine signaling. PMID:22574771

Metabolic function of the CTRP family of hormones

PubMed Central

Seldin, Marcus M.; Tan, Stefanie Y.; Wong, G. William

2013-01-01

Maintaining proper energy balance in mammals entails intimate crosstalk between various tissues and organs. These inter-organ communications are mediated, to a great extent, by secreted hormones that circulate in blood. Regulation of the complex metabolic networks by secreted hormones (e.g., insulin, glucagon, leptin, adiponectin, FGF21) constitutes an important mechanism governing the integrated control of whole-body metabolism. Disruption of hormone-mediated metabolic circuits frequently results in dysregulated energy metabolism and pathology. As part of an effort to identify novel metabolic hormones, we recently characterized a highly conserved family of fifteen secreted proteins, the C1q/TNF-related proteins (CTRP1–15). While related to adiponectin in sequence and structural organization, each CTRP has its own unique tissue expression profile and non-redundant function in regulating sugar and/or fat metabolism. Here, we summarize the current understanding of the physiological functions of CTRPs, emphasizing their metabolic roles. Future studies using gain-of-function and loss-of-function mouse models will provide greater mechanistic insights into the critical role CTRPs play in regulating systemic energy homeostasis. PMID:23963681

Weight and metabolic effects of CPAP in obstructive sleep apnea patients with obesity.

PubMed

Garcia, Jose M; Sharafkhaneh, Hossein; Hirshkowitz, Max; Elkhatib, Rania; Sharafkhaneh, Amir

2011-06-15

Obstructive sleep apnea (OSA) is associated with obesity, insulin resistance (IR) and diabetes. Continuous positive airway pressure (CPAP) rapidly mitigates OSA in obese subjects but its metabolic effects are not well-characterized. We postulated that CPAP will decrease IR, ghrelin and resistin and increase adiponectin levels in this setting. In a pre- and post-treatment, within-subject design, insulin and appetite-regulating hormones were assayed in 20 obese subjects with OSA before and after 6 months of CPAP use. Primary outcome measures included glucose, insulin, and IR levels. Other measures included ghrelin, leptin, adiponectin and resistin levels. Body weight change were recorded and used to examine the relationship between glucose regulation and appetite-regulating hormones. CPAP effectively improved hypoxia. However, subjects had increased insulin and IR. Fasting ghrelin decreased significantly while leptin, adiponectin and resistin remained unchanged. Forty percent of patients gained weight significantly. Changes in body weight directly correlated with changes in insulin and IR. Ghrelin changes inversely correlated with changes in IR but did not change as a function of weight. Weight change rather than elimination of hypoxia modulated alterations in IR in obese patients with OSA during the first six months of CPAP therapy.

Consuming fructose-sweetened, not glucose-sweetened, beverages increases visceral adiposity and lipids and decreases insulin sensitivity in overweight/obese humans

PubMed Central

Stanhope, Kimber L.; Schwarz, Jean Marc; Keim, Nancy L.; Griffen, Steven C.; Bremer, Andrew A.; Graham, James L.; Hatcher, Bonnie; Cox, Chad L.; Dyachenko, Artem; Zhang, Wei; McGahan, John P.; Seibert, Anthony; Krauss, Ronald M.; Chiu, Sally; Schaefer, Ernst J.; Ai, Masumi; Otokozawa, Seiko; Nakajima, Katsuyuki; Nakano, Takamitsu; Beysen, Carine; Hellerstein, Marc K.; Berglund, Lars; Havel, Peter J.

2009-01-01

Studies in animals have documented that, compared with glucose, dietary fructose induces dyslipidemia and insulin resistance. To assess the relative effects of these dietary sugars during sustained consumption in humans, overweight and obese subjects consumed glucose- or fructose-sweetened beverages providing 25% of energy requirements for 10 weeks. Although both groups exhibited similar weight gain during the intervention, visceral adipose volume was significantly increased only in subjects consuming fructose. Fasting plasma triglyceride concentrations increased by approximately 10% during 10 weeks of glucose consumption but not after fructose consumption. In contrast, hepatic de novo lipogenesis (DNL) and the 23-hour postprandial triglyceride AUC were increased specifically during fructose consumption. Similarly, markers of altered lipid metabolism and lipoprotein remodeling, including fasting apoB, LDL, small dense LDL, oxidized LDL, and postprandial concentrations of remnant-like particle–triglyceride and –cholesterol significantly increased during fructose but not glucose consumption. In addition, fasting plasma glucose and insulin levels increased and insulin sensitivity decreased in subjects consuming fructose but not in those consuming glucose. These data suggest that dietary fructose specifically increases DNL, promotes dyslipidemia, decreases insulin sensitivity, and increases visceral adiposity in overweight/obese adults. PMID:19381015

Positive sliding mode control for blood glucose regulation

NASA Astrophysics Data System (ADS)

Menani, Karima; Mohammadridha, Taghreed; Magdelaine, Nicolas; Abdelaziz, Mourad; Moog, Claude H.

2017-11-01

Biological systems involving positive variables as concentrations are some examples of so-called positive systems. This is the case of the glycemia-insulinemia system considered in this paper. To cope with these physical constraints, it is shown that a positive sliding mode control (SMC) can be designed for glycemia regulation. The largest positive invariant set (PIS) is obtained for the insulinemia subsystem in open and closed loop. The existence of a positive SMC for glycemia regulation is shown here for the first time. Necessary conditions to design the sliding surface and the discontinuity gain are derived to guarantee a positive SMC for the insulin dynamics. SMC is designed to be positive everywhere in the largest closed-loop PIS of plasma insulin system. Two-stage SMC is employed; the last stage SMC2 block uses the glycemia error to design the desired insulin trajectory. Then the plasma insulin state is forced to track the reference via SMC1. The resulting desired insulin trajectory is the required virtual control input of the glycemia system to eliminate blood glucose (BG) error. The positive control is tested in silico on type-1 diabetic patients model derived from real-life clinical data.

The over-expression of miR-200a in the hypothalamus of ob/ob mice is linked to leptin and insulin signaling impairment.

PubMed

Crépin, Delphine; Benomar, Yacir; Riffault, Laure; Amine, Hamza; Gertler, Arieh; Taouis, Mohammed

2014-03-25

Early in life, leptin plays a crucial role in hypothalamic neural organization. Leptin, most likely, controls neural gene expression conferring then specific phenotype regarding energy homeostasis. MicroRNAs are new regulators for several physiological functions, including the regulation of metabolism. However, the impact of leptin on hypothalamic microRNA patterns remains unknown. Here, we demonstrate that miR-200a, miR-200b and miR-429 are up-regulated in the hypothalamus of genetically obese and leptin deficient ob/ob mice. Leptin treatment down-regulates these miRNAs in ob/ob hypothalamus. The hypothalamic silencing of miR-200a increased the expression level of leptin receptor and insulin receptor substrate 2, reduced body weight gain, and restored liver insulin responsiveness. In addition, the overexpression of pre-miR-200a in a human neuroblastoma cell line impaired insulin and leptin signaling. These findings link the alteration of leptin and insulin signaling to the up-regulation of hypothalamic miR-200a which could be a new target for treatment of obesity. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Intranasal insulin treatment alleviates methamphetamine induced anxiety-like behavior and neuroinflammation.

PubMed

Beirami, Elmira; Oryan, Shahrbanoo; Seyedhosseini Tamijani, Seyedeh Masoumeh; Ahmadiani, Abolhassan; Dargahi, Leila

2017-11-01

Insulin, as a peptide hormone, has recently gained attention for its pro-cognitive, anti-inflammatory and neuroprotective effects in the central nervous system (CNS). Most studies have indicated anxiogenic and neuroinflammatory effects of methamphetamine (MA) and other psychostimulants, even after periods of abstinence. The present study aimed to examine whether intranasal (IN) insulin treatment with high CNS bioavailability and minimal systemic side effects, can reverse the anxiety-like behavior and neuroinflammation induced by repeated MA administration. In male wistar rats, escalating doses of MA (1-10mg/kg, i.p.) were administrated twice a day for 10 consecutive days. IN insulin treatment (0.5IU/day, for 7days after MA discontinuation) attenuated MA-induced anxiety-like behavior in the elevated plus maze task, and significantly decreased the levels of glial cell markers (GFAP and Iba1), pro-inflammatory cytokines (TNF-α and IL-6) as well as COX2 and NF-κB players of neuroinflammation, in the hippocampus of MA-treated animals. These findings introduce insulin as a potential therapeutic approach for the treatment of MA aversive symptoms. Copyright © 2017 Elsevier B.V. All rights reserved.

Use of dark chocolate for diabetic patients: a review of the literature and current evidence.

PubMed

Shah, Syed Raza; Alweis, Richard; Najim, Najla Issa; Dharani, Amin Muhammad; Jangda, Muhammad Ahmed; Shahid, Maira; Kazi, Ahmed Nabeel; Shah, Syed Arbab

2017-10-01

Dietary changes are a major lifestyle factor that can influence the progression of chronic diseases such as diabetes. Recently, flavanols, a subgroup of plant-derived phytochemicals called flavonoids, have gained increasing attention, due to studies showing an inverse correlation between dietary intake of flavanols and incidence of diabetes. Flavanoids in the cocoa plant may ameliorate insulin resistance by improving endothelial function, altering glucose metabolism, and reducing oxidative stress. Oxidative stress has been proposed as the main culprit for insulin resistance. The well-established effects of cocoa on endothelial function also points to a possible effect on insulin sensitivity. The relationship between insulin resistance and endothelial function is a reciprocal one. Overall, the evidence from these studies suggests that cocoa may be useful in slowing the progression to type 2 diabetes and ameliorating insulin resistance in metabolic syndrome. Additionally, results from several small studies indicate that cocoa may also have therapeutic potential in preventing cardiovascular complications in diabetic patients. Studies highlighting the potential of cocoa-containing diets, in large-randomized controlled trials should be performed which might give us a better opportunity to analyze the potential health-care benefit for reducing the risk of complications in diabetic patients at molecular level.

Short communication: Acute but transient increase in serum insulin reduces messenger RNA expression of hepatic enzymes associated with progesterone catabolism in dairy cows.

PubMed

Vieira, F V R; Cooke, R F; Aboin, A C; Lima, P; Vasconcelos, J L M

2013-02-01

The objective of this experiment was to evaluate the effects of glucose infusion on serum concentrations of glucose, insulin, and progesterone (P4), as well as mRNA expression of hepatic CYP2C19 and CYP3A4 in nonlactating, ovariectomized cows in adequate nutritional status. Eight Gir × Holstein cows were maintained on a low-quality Brachiaria brizantha pasture with reduced forage availability, but they individually received, on average, 3 kg/cow daily (as fed) of a corn-based concentrate from d -28 to 0 of the experiment. All cows had an intravaginal P4-releasing device inserted on d -14, which remained in cows until the end of the experiment (d 1). On d 0, cows were randomly assigned to receive, in a crossover design containing 2 periods of 24h each (d 0 and 1), (1) an intravenous glucose infusion (GLUC; 0.5 g of glucose/kg of BW, over a 3-h period) or (2) an intravenous saline infusion (SAL; 0.9%, over a 3-h period). Cows were fasted for 12h before infusions, and they remained fasted during infusion and sample collections. Blood samples were collected at 0, 3, and 6h relative to the beginning of infusions. Liver biopsies were performed concurrently with blood collections at 0 and 3h. After the last blood collection of period 1, cows received concentrate and returned to pasture. Cows gained BW (16.5 ± 3.6 kg) and BCS (0.08 ± 0.06) from d -28 to 0. Cows receiving GLUC had greater serum glucose and insulin concentrations at 3h compared with SAL cohorts. No treatment effects were detected for serum P4 concentrations, although mRNA expression of CYP2C19 and CYP3A4 after the infusion period was reduced for cows in the GLUC treatment compared with their cohorts in the SAL treatment. In conclusion, hepatic CYP3A4 and CYP2C19 mRNA expression can be promptly modulated by glucose infusion followed by acute increases in circulating insulin, which provides novel insight into the physiological mechanisms associating nutrition and reproductive function in dairy cows. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Resveratrol attenuates intermittent hypoxia-induced macrophage migration to visceral white adipose tissue and insulin resistance in male mice.

PubMed

Carreras, Alba; Zhang, Shelley X L; Almendros, Isaac; Wang, Yang; Peris, Eduard; Qiao, Zhuanhong; Gozal, David

2015-02-01

Chronic intermittent hypoxia during sleep (IH), as occurs in sleep apnea, promotes systemic insulin resistance. Resveratrol (Resv) has been reported to ameliorate high-fat diet-induced obesity, inflammation, and insulin resistance. To examine the effect of Resv on IH-induced metabolic dysfunction, male mice were subjected to IH or room air conditions for 8 weeks and treated with either Resv or vehicle (Veh). Fasting plasma levels of glucose, insulin, and leptin were obtained, homeostatic model assessment of insulin resistance index levels were calculated, and insulin sensitivity tests (phosphorylated AKT [also known as protein kinase B]/total AKT) were performed in 2 visceral white adipose tissue (VWAT) depots (epididymal [Epi] and mesenteric [Mes]) along with flow cytometry assessments for VWAT macrophages and phenotypes (M1 and M2). IH-Veh and IH-Resv mice showed initial reductions in food intake with later recovery, with resultant lower body weights after 8 weeks but with IH-Resv showing better increases in body weight vs IH-Veh. IH-Veh and IH-Resv mice exhibited lower fasting glucose levels, but only IH-Veh had increased homeostatic model assessment of insulin resistance index vs all 3 other groups. Leptin levels were preserved in IH-Veh but were significantly lower in IH-Resv. Reduced VWAT phosphorylated-AKT/AKT responses to insulin emerged in both Mes and Epi in IH-Veh but normalized in IH-Resv. Increases total macrophage counts and in M1 to M2 ratios occurred in IH-Veh Mes and Epi compared all other 3 groups. Thus, Resv ameliorates food intake and weight gain during IH exposures and markedly attenuates VWAT inflammation and insulin resistance, thereby providing a potentially useful adjunctive therapy for metabolic morbidity in the context of sleep apnea.

Solutes transport characteristics in peritoneal dialysis: variations in glucose and insulin serum levels.

PubMed

da Silva, Dirceu R; Figueiredo, Ana E; Antonello, Ivan C; Poli de Figueiredo, Carlos E; d'Avila, Domingos O

2008-01-01

Differences in small solutes transport rate (SSTR) during peritoneal dialysis (PD) may affect water and solutes removal. Patients with high SSTR must rely on shorter dwell times and increased dialysate glucose concentrations to keep fluid balance. Glucose absorption during peritoneal dialysis (PD), besides affecting glucose and insulin metabolism, may induce weight gain. The study aimed at examining acute glucose and insulin serum level changes and other potential relationships in PD patients with diverse SSTR. This cross-sectional study used a modified peritoneal equilibration test (PET) that enrolled 34 prevalent PD patients. Zero, 15, 30, 60, 120, 180, and 240-minute glucose and insulin serum levels were measured. Insulin resistance index was assessed by the homeostasis model assessment (HOMA-IR) formula. SSTR categories were classified by quartiles of the four-hour dialysate/serum creatinine ratio (D(4)/P(Cr)). Demographic and clinical variables were evaluated, and the body mass index (BMI) was estimated. Correlations among variables of interest and categories of SSTR were explored. Glucose serum levels were significantly different at 15, 30, and 60 minutes between high and low SSTR categories (p = 0.014, 0.009, and 0.022). Increased BMI (25.5 +/- 5.1) and insulin resistance [HOMA-IR = 2.60 (1.40-4.23)] were evidenced overall. Very strong to moderate correlations between insulin levels along the PET and HOMA-IR (r = 0.973, 0.834, 0.766, 0.728, 0.843, 0.857, 0.882) and BMI (r = 0.562, 0.459, 0.417, 0.370, 0.508, 0.514, 0.483) were disclosed. CONCLUSIONS; Early glucose serum levels were associated with SSTR during a PET. Overweight or obesity and insulin resistance were prevalent. An association between insulin serum levels and BMI was demonstrated.