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Sample records for alloxan-induced diabetic mice

  1. Anti-diabetic effects of rice hull smoke extract in alloxan-induced diabetic mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We investigated the protective effect of a liquid rice hull smoke extract (RHSE) against diabetes in alloxan-induced diabetic mice. Anti-diabetic effects of RHSE were evaluated in both the rat insulinoma-1 cell line (INS-1) and diabetic ICR mice induced by inraperitoneal (ip) injection of alloxan. ...

  2. Effect of Potentilla fulgens on lipid peroxidation and antioxidant status in alloxan-induced diabetic mice

    PubMed Central

    Saio, Valrielyn; Syiem, Donkupar; Sharma, Ramesh

    2012-01-01

    Potentilla fulgens (Rosaceae) root traditionally used as a folk remedy by local health practitioners of Khasi Hills, Meghalaya was investigated for its effects on lipid peroxidation and antioxidant status in alloxan-induced diabetic mice. Significant increase in levels of thiobarbituric acid reactive substances (TBARS) and decrease in activities of glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT) were observed under diabetic condition. Intraperitoneal administration of methanol extract of P. fulgens roots at a dose of 250 mg/kg body weight to male swiss albino diabetic mice for 14 days caused significant reduction in the elevated TBARS level, while increasing the activities of the antioxidant enzymes in diabetic mice. Maximum reduction in TBARS level was observed in liver tissue (75%, p<0.001). Kidney exhibited the highest elevation in the activity for catalase (68%, p<0.001) and superoxide dismutase (29%, p<0.001) while maximum increase in glutathione peroxidase activity was seen in brain (50%, p<0.001). The effects of P. fulgens was compared against known antioxidant, vitamin C. Results indicate that Potentilla fulgens methanolic root extract can reduce free radical mediated oxidative stress in experimental diabetes mellitus. PMID:24826032

  3. Lectin from Crataeva tapia Bark Improves Tissue Damages and Plasma Hyperglycemia in Alloxan-Induced Diabetic Mice

    PubMed Central

    da Rocha, Amanda Alves; Araújo, Tiago Ferreira da Silva; da Fonseca, Caíque Silveira Martins; da Mota, Diógenes Luís; de Medeiros, Paloma Lys; Paiva, Patrícia Maria Guedes; Coelho, Luana Cassandra Breitenbach Barroso; Correia, Maria Tereza dos Santos; Lima, Vera Lúcia de Menezes

    2013-01-01

    Crataeva tapia is a plant popularly used for diabetes treatment, in Brazil. Progressive decline in renal and hepatic functions has been described in patients with diabetes mellitus, and mortality rate is increased in patients with chronic liver and renal disease. This study aimed to evaluate whether Crataeva tapia bark lectin (CrataBL) improves hyperglycemia and renal and hepatic damage in diabetic mice. CrataBL was purified by ion exchange chromatography on CM-cellulose, and intraperitoneal administration of CrataBL to alloxan-induced diabetic mice at dose of 10?mg/Kg/day and 20?mg/Kg/day for 10 days significantly reduced serum glucose levels by 14.9% and 55.9%, respectively. Serum urea, creatinine, aspartate aminotransferase, and alanine aminotransferase were also significantly reduced after treatment with both doses of CrataBL. Furthermore, histological analysis of liver, kidney, and pancreas revealed an improvement in the tissue morphology upon treatment with CrataBL. The results suggest that CrataBL has a beneficial hypoglycemic activity and improves the renal and hepatic complications of diabetes. Therefore, this lectin may be a promising agent for the treatment of diabetes, and this might be the basis for its use in the folk medicine as an alternative treatment to manage diabetes-related complications such as hyperglycemia and tissue damage. PMID:24324521

  4. Timosaponin B-II ameliorates diabetic nephropathy via TXNIP, mTOR, and NF-?B signaling pathways in alloxan-induced mice

    PubMed Central

    Yuan, Yong-Liang; Guo, Chang-Run; Cui, Ling-Ling; Ruan, Shi-Xia; Zhang, Chun-Feng; Ji, De; Yang, Zhong-Lin; Li, Fei

    2015-01-01

    Background Many synthesized drugs with clinical severe side effects have been used for diabetic nephropathy (DN) treatment. Therefore, it is urgent and necessary to identify natural and safe agents to remedy DN. Timosaponin B-II (TB-II), a major steroidal saponin constituent in Anemarrhena asphodeloides Bunge, exhibits various activities, including anti-inflammatory and hypoglycemic functions. However, the anti-DN effects and potential mechanism(s) of TB-II have not been previously reported. Purpose To investigate the effect of TB-II on DN in alloxan-induced diabetic mice. Methods TB-II was isolated and purified from A. asphodeloides Bunge using macroporous adsorption resin and preparative high-performance liquid chromatography. The effect of TB-II on DN was evaluated in alloxan-induced diabetic mice using an assay kit and immunohistochemical determination in vivo. The expression of mammalian target of rapamycin (mTOR), thioredoxin-interacting protein (TXNIP), and nuclear transcription factor-?B (NF-?B) signaling pathways was also measured using Western blot analysis. Results TB-II significantly decreased the blood glucose levels and ameliorated renal histopathological injury in alloxan-induced diabetic mice. In addition, TB-II remarkably decreased the levels of renal function biochemical factors, such as kidney index, blood urea nitrogen, serum creatinine, urinary uric acid, urine creatinine, and urine protein, and it reduced lipid metabolism levels of total cholesterol and triglycerides and the levels of inflammatory cytokines interleukin-6 and tumor necrosis factor-? in alloxan-induced mice. Furthermore, TB-II inhibited the expression of mTOR, TXNIP, and NF-?B. Conclusion The results revealed that TB-II plays an important role in DN via TXNIP, mTOR, and NF-?B signaling pathways. Overall, TB-II exhibited a prominently ameliorative effect on alloxan-induced DN. PMID:26664046

  5. Hypoglycemic activity of the Anisopus mannii N. E. Br. methanolic leaf extract in normal and alloxan-induced diabetic mice.

    PubMed

    Zaruwa, Moses Z; Manosroi, Aranya; Akihisa, Toshihiro; Manosroi, Worapaka; Rangdaeng, Samreung; Manosroi, Jiradej

    2013-01-01

    The hypoglycemic activities of nine sub-fractions from the methanolic leaf crude extract of Anisopus mannii were investigated in normoglycemic and alloxan-induced diabetic mice. The methanolic sub-fraction M at 400 mg/kg bw showed significantly (p<0.05) high reduction in fasting blood glucose (FBG) at 27.36 and 65.57% in normoglycemic and diabetic mice, respectively. In acute toxicity test, M at 2,000 and 5,000 mg/kg bw showed reduction in blood urea nitrogen and creatinine level, elevations in aspartate transaminase, alanine transaminase and total bilirubin levels, as well as the body weights. The weight-ratios of kidney and liver to the body weight of the mice fed with these doses of M were reduced with no sign of histopathological alteration. The M at 250 mg/kg bw significantly reduced the FBG levels in a postprandial study. The hypoglycemic effect of M was eliminated when co-administered with isosorbide dinitrate or nifedipine indicating the induction of insulin secretion via K+ ATP-dependent channels. The UV/HPLC analysis of M indicated saponin at 7.7 mg/g. This study confirmed the traditional use of A. mannii for diabetes mellitus and the potential for the further development as a novel hypoglycemic drug. PMID:23828328

  6. Hypoglycemic Properties of Oxovanadium (IV) Coordination Compounds with Carboxymethyl-Carrageenan and Carboxymethyl-Chitosan in Alloxan-Induced Diabetic Mice

    PubMed Central

    Zhang, Hongyu; Yi, Yuetao; Feng, Dawei; Wang, Yipeng; Qin, Song

    2011-01-01

    In order to avoid low absorption, incorporation, and undesirable side effects of inorganic oxovanadium compounds, the antidiabetic activities of organic oxovanadium (IV) compounds in alloxan-induced diabetic mice were investigated. Vanadyl carboxymethyl carrageenan (VOCCA) and vanadyl carboxymethyl chitosan (VOCCH) were synthesized and administrated through intragastric administration in different doses for 20 days in alloxan-induced diabetic mice. Glibenclamide was administrated as the positive control. Our results showed that low-dose group, middle-dose group, and high-dose group of VOCCA and VOCCH could significantly reduce the levels of blood glucose (P < 0.05) compared with untreated group, but not in normal mice. Besides, high-dose groups of VOCCA and VOCCH exhibited more significant hypoglycemic activities (P < 0.01). After treated with VOCCH, the oral glucose tolerance of high-dose group of VOCCH was improved compared with model control group (P < 0.05). PMID:21804857

  7. The effects of the king oyster mushroom Pleurotus eryngii (higher Basidiomycetes) on glycemic control in alloxan-induced diabetic mice.

    PubMed

    Li, Jian-Ping; Lei, Ya-li; Zhan, Huan

    2014-01-01

    The purpose of this study is to investigate the effects of Pleurotus eryngii on glycemic metabolism. Alloxan-induced hyperglycemic mice were used to study the effects of P. eryngii on blood glucose, glycohemoglobin, insulin secretion, damaged pancreatic ?-cells, total antioxidant status (TAOS), and hepatic glycogen in hyperglycemic mice. Sixty diabetic mice were divided equally into 5 groups: the alloxan (AX)-induced hyperglycemic group, the AX and glibenclamide (GLI)-treated group, the AX and P. eryngii extracts (PEEs) 50-treated group (PEE 50 mg/kg), the AX and PEE100-treated group (PEE 100 mg/kg), and the AX and PEE200-treated group (PEE 200 mg/kg). The other 12 normal mice were injected intravenously with the normal saline and used as the control group. After PEE (100 and 200 mg/kg) was orally administered to the mice over 5 weeks, blood glucose and HbAlc were significantly decreased in AX-induced hyperglycemic mice (P < 0.05 and P < 0.01, respectively), whereas the level of insulin secretion was markedly elevated in (P < 0.05). The pancreatic ?-cells damaged by AX partially and gradually recovered after PPE extract was administered to the hyperglycemic mice for 35 days. In addition, PEE treatment gradually increased the body weight and significantly increased the concentration of hepatic glycogen in hyperglycemic mice (P < 0.05). The results suggest that the action of PPE on glycemic metabolism occurs via increasing glycogen and insulin concentrations as well as recovering injured ?-cells and reducing free radical damage. PPE may become a new potential hypoglycemic food for hyperglycemic people. PMID:24941163

  8. Hypoglycemic Effect of Aqueous and Methanolic Extract of Artemisia afra on Alloxan Induced Diabetic Swiss Albino Mice

    PubMed Central

    Issa, Idris Ahmed; Hussen Bule, Mohammed

    2015-01-01

    Diabetes mellitus is metabolic syndrome that causes disability, early death, and many other complications. Currently insulin and many synthetic drugs are used in diabetes treatment. However, these pharmaceutical drugs are too expensive particularly for sub-Saharan population in addition to their undesirable side effects. The present study was aimed to evaluate antidiabetic effect and toxicity level of Artemisia afra which was collected from its natural habitat in Bale Zone, around Goba town, 455?km southeast of Addis Ababa. Air dried aerial parts of Artemisia afra were separately extracted with both distilled water and 95% methanol. Oral acute toxicity test was conducted on healthy Swiss albino mice. Antidiabetic effect of the aqueous and methanolic extracts of Artemisia afra was separately evaluated on alloxan induced diabetic mice at doses of 500, 750, and 1000?mg/Kg body weight orally. The results indicate that mean lethal dose (LD50) for aqueous extract of Artemisia afra was 9833.4?mg/Kg. Blood glucose level was significantly decreased by 24% (p < 0.005) and 56.9% (p < 0.0004) in groups that received aqueous extract of Artemisia afra at dose of 500?mg/Kg and 750?mg/Kg, respectively. The methanolic extract of Artemisia afra also significantly lowered blood glucose by 49.8% (p < 0.0001) at doses of 1000?mg/kg on the 5th?hr. Aqueous extract of Artemisia afra was regarded as nontoxic and safe since its LD50 was found above 5000?mg/Kg. Aqueous extract showed higher effect at relatively lower dose as compared to methanolic extract. The aqueous extract was screened positive for phytochemicals like flavonoids, polyphenols, and tannins that were reported to have antioxidant activity. PMID:26345313

  9. Comparative study of antidiabetic activity of Cajanus cajan and Tamarindus indica in alloxan-induced diabetic mice with a reference to in vitro antioxidant activity

    PubMed Central

    Nahar, Laizuman; Nasrin, Fatema; Zahan, Ronok; Haque, Anamul; Haque, Ekramul; Mosaddik, Ashik

    2014-01-01

    Background: Oxidative stress not only develops complications in diabetic (type 1 and type 2) but also contributes to beta cell destruction in type 2 diabetes in insulin resistance hyperglycemia. Glucose control plays an important role in the pro-oxidant/antioxidant balance. Some antidiabetic agents may by themselves have antioxidant properties independently of their role on glucose control. Objective: The present investigation draws a comparison of the protective antioxidant activity, total phenol content and the antihyperglycemic activity of the methanolic extract of Cajanus cajan root (MCC) and Tamarindus indica seeds (MTI). Materials and Methods: Antidiabetic potentials of the plant extracts were evaluated in alloxan-induced diabetic Swiss albino mice. The plant extracts at the doses of 200 and 400 mg/kg body weight was orally administered for glucose tolerance test during 1-hour study and hypoglycemic effect during 5-day study period in comparison with reference drug Metformin HCl (50 mg/kg). In vitro antioxidant potential of MCC and MTI was investigated by using 1, 1- diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity at 517 nm. Total phenolic content, total antioxidant capacity and reducing power activity was also assayed. Results: There was a significant decrease in fasting serum glucose level (P < 0.001), reduction in blood glucose level (P < 0.001) in 5-days study, observed in the alloxan-induced diabetic mice. The reduction efficacy of blood glucose level of both the extracts is proportional to their dose but MCC is more potent than MTI. Antioxidant study and quantification of phenolic compound of both the extracts revealed that they have high antioxidant capacity. Conclusion: These studies showed that MCC and MTI have both hypoglycemic and antioxidant potential but MCC is more potent than MTI. The present study suggests that both MCC and MTI could be used in managing oxidative stress. PMID:24761124

  10. Isolation, purification, and structural features of a polysaccharide from Phellinus linteus and its hypoglycemic effect in alloxan-induced diabetic mice.

    PubMed

    Zhao, Chao; Liao, Zunsheng; Wu, Xiaoqi; Liu, Yanling; Liu, Xiaoyan; Lin, Zhanxi; Huang, Yifan; Liu, Bin

    2014-05-01

    Phellinus linteus is a medicinal mushroom that has been used in Oriental countries for centuries for its antitumor, antioxidant, immunomodulatory, and biological activity on hyperglycemia. A water-soluble crude polysaccharide was extracted using hot water from P. linteus mycelia grown under submerged culture. An orthogonal experiment was used to optimize the extraction conditions of P. linteus mycelia polysaccharides (PLP). The crude polysaccharide was purified using DEAE Sephadex A-50 and Sephadex G-200 chromatography. Fourier transform infrared (FT-IR) spectroscopy and nuclear magnetic resonance ((1) H NMR) spectroscopy were used to investigate the structure of the purified P. linteus polysaccharide (PLP-I), revealing that it was mainly a branched-type glycan with both ?- and ?-linkages and a pyranoid sugar ring conformation. PLP orally administered at 100 mg/kg body weight/d could significantly reduce the blood glucose level by 35.60% in alloxan-induced diabetic mice. The results of an oral glucose tolerance test (OGTT) revealed that PLP had an effect on glucose disposal after 28 d of treatment. The result revealed that PLP from a submerged culture of P. linteus mycelia possessed potent hypoglycemic properties. The polysaccharide may be useful as a functional food additive and a hypoglycemic agent. PMID:24761950

  11. Effects of iscador and vincristine and 5-fluorouracil on brain, liver, and kidney element levels in alloxan-induced diabetic mice.

    PubMed

    Gre?, Agnieszka; Formicki, Grzegorz

    2013-05-01

    Exposure to substance toxicity is especially dangerous for diabetics because it accelerates and intensifies diabetic complication. Homeostasis of trace elements can be disrupted by diabetes mellitus. On the other hand, disturbance in trace element status in diabetes mellitus may contribute to insulin resistance and development of diabetic complications. The aim of the present study was to compare the concentration of elements in the brain, liver, and kidneys of animals with induced diabetes after the administration of plant preparations (iscador and vincristine) and 5-fluorouracil. The experiments were carried out on male mice. The animals were divided into five groups of ten mice each: one control and four experimental groups. The first experimental group was administered alloxan at 75 mg/kg b.w. for 4 days, the second group was administered both alloxan at 75 mg/kg b.w. and vincristine 1 mg/kg b.w. for 4 days, and the third group was administered both alloxan at 75 mg/kg b.w. and 5-fluorouracil 75 mg/kg b.w. for 4 days. The animals of the fourth group were administered both alloxan at 75 mg/kg b.w. and iscador Qu at 5 mg/kg b.w. for 4 days. Calcium, magnesium, iron, copper, zinc, sodium, and potassium levels in the tissues were analyzed by flame atomic absorption spectrophotometer. We observed that zinc, copper, magnesium, sodium, and potassium were lower in the brain as compared to the control animals. The copper levels in the liver were also lower in diabetic groups than in control groups. However, the iscador and vincristine and 5-fluorouracil did not induce significant differences in the five groups. In conclusion, results of the current study indicated that changes of the investigated essential elements may contribute to explaining the role of impaired element metabolism of some elements in the progression of diabetic complications. PMID:23334865

  12. The Control of Hyperglycemia by Estriol and Progesterone in Alloxan induced Type I Diabetes Mellitus Mice Model through Hepatic Insulin Synthesis

    PubMed Central

    Bhattacharya, Suman; Bank, Sarbashri; Maiti, Smarajit; Sinha, Asru K.

    2014-01-01

    As much as 20% of the women in menopause are reported to develop type I diabetes mellitus. The cessation of the ovarian syntheses of the female sex hormones is known to cause menopause in women, and the roles of estriol (one of the most abundant estrogens) and progesterone were investigated for hepatic insulin synthesis through estriol and progesterone induced synthesis of nitric oxide in the liver cells. Type 1 Diabetic mellitus mice were prepared by alloxan treatment, Nitric oxide was determined by methemoglobin method. Insulin was determined by enzyme linked immunosorbant assay. Injection of either 3.5 µM estriol or 3.5 nM progesterone to the diabetic mice which cannot synthesize pancreatic insulin, reduced the blood glucose level from 600 mg/dl to 120 mg/dl and 500 ± 25 mg/dl to 120 ± 6 mg/dl in 6 and 10 h respectively with simultaneous increase of the plasma insulin from 0 µunits/ml to 40 µunits/ml and 0 µunits/ml to 9.5 µunits/ml in the case of estriol and progesterone respectively with stimulated NO synthesis. The inhibition of the steroids induced NO synthesis by using NAME (NG-methyl-l-arginine acetate ester) in the reaction mixture resulted in the inhibition of hepatic insulin synthesis. Use of pure NO solution in 0.9% NaCl instead of either estriol or progesterone in the reaction mixture was found to stimulate the hepatic insulin synthesis. Both estriol and progesterone might be involved in the prevention of type 1 diabetes mellitus through the hepatic insulin synthesis even when the pancreatic insulin synthesis was impaired. PMID:24711743

  13. Protective effects of Piper nigrum and Vinca rosea in alloxan induced diabetic rats.

    PubMed

    Kaleem, M; Sheema; Sarmad, H; Bano, B

    2005-01-01

    In the present study aqueous extract of Piper nigrum seeds and Vinca rosea flowers were administered orally to alloxan induced diabetic rats once a day for 4 weeks. These treatments lead to significant lowering of blood sugar level and reduction in serum lipids. The levels of antioxidant enzymes, catalase and glutathione peroxidase decreased in alloxan induced diabetic rats however these levels returned to normal in insulin, P. nigrum and V. rosea treated rats. There was no significant difference in superoxide dismutase activity in all groups compared to controls. Lipid peroxidation levels were significantly higher in diabetic rats and it was slightly increased in insulin, P. nigrum and V. rosea treated rats as compared to control rat. These results suggest that oxidative stress plays a key role in diabetes, and treatment with P. nigrum and V. rosea are useful in controlling not only the glucose and lipid levels but these components may also be helpful in strengthening the antioxidants potential. PMID:15881860

  14. Antidiabetic Activity of Differently Regioselective Chitosan Sulfates in Alloxan-Induced Diabetic Rats

    PubMed Central

    Xing, Ronge; He, Xiaofei; Liu, Song; Yu, Huahua; Qin, Yukun; Chen, Xiaolin; Li, Kecheng; Li, Rongfeng; Li, Pengcheng

    2015-01-01

    The present study investigated and compared the hypoglycemic activity of differently regioselective chitosan sulfates in alloxan-induced diabetic rats. Compared with the normal control rats, significantly higher blood glucose levels were observed in the alloxan-induced diabetic rats. The differently regioselective chitosan sulfates exhibited hypoglycemic activities at different doses and intervals, especially 3-O-sulfochitosan (3-S). The major results are as follows. First, 3,6-di-O-sulfochitosan and 3-O-sulfochitosan exhibited more significant hypoglycemic activities than 2-N-3, 6-di-O-sulfochitosan and 6-O-sulfochitosan. Moreover, 3-S-treated rats showed a more significant reduction of blood glucose levels than those treated by 3,6-di-O-sulfochitosan. These results indicated that –OSO3? at the C3-position of chitosan is a key active site. Second, 3-S significantly reduced the blood glucose levels and regulated the glucose tolerance effect in the experimental rats. Third, treatment with 3-S significantly increased the plasma insulin levels in the experimental diabetic rats. A noticeable hypoglycemic activity of 3-S in the alloxan-induced diabetic rats was shown. Clinical trials are required in the future to confirm the utility of 3-S. PMID:25988523

  15. Antidiabetic Activity of Vinca rosea Extracts in Alloxan-Induced Diabetic Rats

    PubMed Central

    Ahmed, Mohammed Fazil; Kazim, Syed Mohammed; Ghori, Syed Safiullah; Mehjabeen, Syeda Sughra; Ahmed, Shaik Rasheed; Ali, Shaik Mehboob; Ibrahim, Mohammed

    2010-01-01

    The present study was carried out to evaluate the antidiabetic activity of Vinca rosea methanolic whole plant extracts in alloxan induced diabetic rats for 14 days. The methanolic whole plant extract at high dose (500?mg/kg) exhibited significant anti-hyperglycemic activity than whole plant extract at low dose (300?mg/kg) in diabetic rats. The methanolic extracts also showed improvement in parameters like body weight and lipid profile as well as regeneration of ?-cells of pancreas in diabetic rats. Histopathological studies reinforce the healing of pancreas, by methanolic Vinca rosea extracts, as a possible mechanism of their antidiabetic activity. PMID:20652054

  16. Antidiabetic and antihyperlipidemic effects of Thespesia populnea fruit pulp extracts on alloxan-induced diabetic rats.

    PubMed

    Belhekar, S N; Chaudhari, P D; Saryawanshi, J S; Mali, K K; Pandhare, R B

    2013-03-01

    Present study was carried to find out the antihyperglycemic and antihyperlipidemic activity of ethanol and aqueous extract of Thespesia populnea fruit pulp on alloxan-induced diabetic rats. Diabetes was induced in rats by administration of alloxan (150 mg/kg, i.p.). After the successful induction of experimental diabetes, the rats were divided into five groups each comprising a minimum of six rats. Phytochemical analysis and acute toxicity study of extracts was also done. The effects of extracts and metformin on fasting blood glucose and plasma lipid were examined for 28 days. Statistical analysis was carried out by using analysis of variance followed by Dunnet's multiple comparison test and paired t-test were done as the test of significance using GraphPad Prism. P?0.05 was considered as the minimal level of statistical significance. Therapeutic dose of extract was found to be 200 mg/kg on the basis of acute toxicity study. Aqueous and alcoholic extract showed a significant reduction in blood glucose levels as well as a lipid profile of diabetic rats at the end of 28(th) day of treatment. However, in groups treated with plant extract the reduction in the blood glucose and improvement in lipid profile was slightly less than that achieved with the standard group (metformin). From this study, it can be concluded that ethanol and aqueous extract of Thespesia populnea exhibited significant antihyperglycemic and antihyperlipidemic effects on alloxan-induced diabetic rats. PMID:24019572

  17. Effect of Aegle marmelos (L.) Correa on alloxan induced early stage diabetic nephropathy in rats.

    PubMed

    Bhatti, Rajbir; Sharma, Shikha; Singh, Jatinder; Singh, Amarjit; Ishar, M P S

    2013-06-01

    Diabetic nephropathy (DN) has a complex pathogenesis and poor prognosis due to the lack of therapeutic interventions. The present study investigates the effect of A. marmelos leaf extract (AME) on early alloxan induced DN. The treatment with AME was found to significantly decrease the fasting blood sugar, total cholesterol, blood urea, creatinine and renal TBARS and increased the levels of renal reduced glutathione and catalase significantly as compared to the diabetic control group. The maximum dose-dependent protection was observed at a dose of 200 mg kg(-1). Histological examination revealed marked reversal of the morphological derangements with AME treatment as indicated by a decrease in glomerular expansion, tubular dilatation and inflammatory cells. The present results conclude that AME treatment has a significant ameliorative effect on early changes induced in the kidneys by alloxan and improves the outcome of DN. PMID:23926695

  18. Gum Arabic extracts protect against hepatic oxidative stress in alloxan induced diabetes in rats.

    PubMed

    Ahmed, Abdelkareem A; Fedail, Jaafar S; Musa, Hassan H; Kamboh, Asghar Ali; Sifaldin, Amal Z; Musa, Taha H

    2015-12-01

    Gum Arabic (GA) from Acacia seyal and Acacia senegal is a branched-chain polysaccharide which has strong antioxidant properties, and has been used to reduce the experimental toxicity. Yet, the effects of GA on oxidative stress in type I diabetic rats have not been reported. The aim of the study was to investigate the effects of GA on oxidative stress in Alloxan induced diabetes in rats. The rats were divided into 3 groups (n=20 of each): control group, diabetic group injected with allaoxan, and diabetic group given 15% GA in drinking water for 8 weeks. Oxidative damage to liver tissue was evaluated by measurement of key hepatic enzymes, lipid peroxidation, antioxidant enzymes and expression of oxidative stress genes. Activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were significantly (P<0.05) increased in GA group compared to diabetic and control groups. Treatment of GA decreased liver malondialdehyde (MDA), and increased glutathione (GSH). In addition, GA was significantly (P<0.05) reduced the activities of key liver enzymes, including alanine transaminase (ALT) and aspartate transaminase (AST). SOD, GPx and heat shock protein 70 (HSP70) mRNA were significantly increased in GA group compared to control and diabetic groups. Liver of all diabetic rats showed marked degeneration whereas slight degeneration was observed in GA treated rats compared to control. The results suggest that GA may protect liver by modulating the expression of oxidative stress genes, and thus can improve antioxidant status. PMID:26321624

  19. Antioxidant, Antihyperlipidaemic and Antidiabetic Activity of Eugenia Floccosa Bedd Leaves in Alloxan Induced Diabetic Rats

    PubMed Central

    Jelastin, Kala S Mary; Tresina, P.S.; Mohan, V.R.

    2011-01-01

    The ethanol extract of Eugenia floccosa Bedd (Family: Myrtaceae) leaf was investigated for its antioxidant, antihyperlipidaemic and antidiabetic effect in Wistar Albino rats. Diabetes was induced in Albino rats by administration of alloxan monohydrate (150mg/kg, i.p). The ethanol extracts of E. floccosa at a dose of 150 and 300mg/kg of body weight were administered at single dose per day to diabetes induced rats for a period of 14 days. The effect of ethanol extract of E. floccosa leaf extract on blood glucose, plasma insulin, creatinine, glycosylated haemoglobin, urea serum lipid profile [total cholesterol (TR), triglycerides (TG), low density lipoprotein – cholesterol (LDL-C), very low density lipoprotein – cholesterol (VLDL-C), high density lipoprotein – cholesterol (HDL-C) and phospholipid (PL)] serum protein, albumin, globulin, serum enzymes [serum glutamate pyruvate transaminases (SGPT) and serum glutamate oxaloacetate transaminases (SGOT), and alkaline phosphatase (ALP)], lipoprotein peroxidation (LPO) antioxidant enzymes (catalase (CAT), superoxide dismutase (SOD), reduced glutathione (GSH) and glutathione peroxidase (GPx) were measured in the diabetic rats. The ethanol extract of Eugenia floccosa leaf elicited significant reductions of blood glucose (P<0.05), lipid parameters except HDL-C, serum enzymes and significantly increased HDL-C and antioxidant enzymes. The extracts also caused significant increase in plasma insulin (P<0.05) in the diabetic rats. From the above results, it is concluded that ethanol extract of Eugenia floccosa possesses significant antidiabetic, antihyperlipidaemic and antioxidant effects in alloxan induced diabetic rats. PMID:24826030

  20. Anti-diabetic potentials of Momordica charantia and Andrographis paniculata and their effects on estrous cyclicity of alloxan-induced diabetic rats.

    PubMed

    Reyes, B A S; Bautista, N D; Tanquilut, N C; Anunciado, R V; Leung, A B; Sanchez, G C; Magtoto, R L; Castronuevo, P; Tsukamura, H; Maeda, K-I

    2006-04-21

    Momordica charantia and Andrographis paniculata are the commonly used herbs by the diabetic patients in Pampanga, Philippines. While the anti-diabetic potential of Momordica charantia is well established in streptozocin- or alloxan-induced diabetic animals, the anti-diabetic potential of Andrographis paniculata in alloxan-induced diabetic rat is not known. Neither the effects of these herbs on estrous cyclicity of alloxan-induced diabetic rats are elucidated. Thus, in these experiments, Momordica charantia fruit juice or Andrographis paniculata decoction was orally administered to alloxan-induced diabetic rats. Rats that were treated with Momordica charantia and Andrographis paniculata had higher body weight (BW) compared with diabetic positive control (P < 0.01) from day 22 to day 27 (D27) but exhibited lower BW than the non-diabetic control (P < 0.05). These rats had lower feed (P < 0.05) and liquid intakes (P < 0.01) compared with diabetic positive control from day 17 to D27, but similar with the non-diabetic control. The blood glucose levels in these groups were significantly reduced from day 12 to D27 compared with diabetic positive control (P < 0.01), however, comparable with non-diabetic control. The diabetic positive control had extended mean estrous cycles (8 days) compared to Momordica charantia and Andrographis paniculata-treated diabetic rats (5 days; P < 0.05). Our results suggest that the anti-diabetic potentials of Momordica charantia and Andrographis paniculata could restore impaired estrous cycle in alloxan-induced diabetic rats. PMID:16298503

  1. Hypoglycemic activity of curcumin synthetic analogues in alloxan-induced diabetic rats.

    PubMed

    Das, Kusal K; Razzaghi-Asl, Nima; Tikare, Swati N; Di Santo, Roberto; Costi, Roberta; Messore, Antonella; Pescatori, Luca; Crucitti, Giuliana Cuzzucoli; Jargar, Jameel G; Dhundasi, Salim A; Saso, Luciano

    2016-02-01

    The currently available therapies for type 2 diabetes have been unable to achieve normoglycemic status in the majority of patients. The reason may be attributed to the limitations of the drug itself or its side effects. In an effort to develop potent and safe oral antidiabetic agents, we evaluated the in vitro and in vivo hypoglycemic effects of 10 synthetic polyphenolic curcumin analogues on alloxan-induced male diabetic albino rats. In vitro studies showed 7-bis(3,4-dimethoxyphenyl)hepta-1,6-diene-3,5-dione (4) to be the most potential hypoglycemic agent followed by 1,5-bis(4-hydroxy-3-methoxyphenyl)penta-1,4-dien-3-one (10). Structure activity relationship (SAR) of the tested compounds was elucidated and the results were interpreted in terms of in vitro hypoglycemic activities. Furthermore, oral glucose tolerance test (OGTT) with compounds 4, 10 and reference hypoglycemic drug glipizide showed that compound 4 and glipizide had relatively similar effects on the reduction of blood glucose levels within 2?h. Thus, compound 4 might be regarded as a potential hypoglycemic agent being able to reduce glucose concentration both in vitro and in vivo. PMID:25683079

  2. Hypoglycemic, antilipidemic and antioxidant effects of valproic acid in alloxan-induced diabetic rats.

    PubMed

    Akindele, Abidemi J; Otuguor, Edafe; Singh, Dhirendra; Ota, Duncan; Benebo, Adokiye S

    2015-09-01

    This study was designed to investigate the hypoglycemic, antilipidemic and antioxidant effects of valproic acid (VA) in alloxan-induced diabetic rats. VA (100, 300 and 600mg/kg p.o.) and insulin (17IU/kg s.c.) were administered once daily for 21 days. Fasting blood glucose level was determined at 7 days interval. On day 21, blood samples were collected for assay of serum biochemical parameters (total protein, creatinine, urea, alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), triglycerides (TG), total cholesterol (TC), high density lipoprotein (HDL), and low density lipoprotein (LDL)). Kidneys and livers were harvested for antioxidant indices and histopathological examination. In diabetic rats, VA produced a dose and day-dependent reduction in glucose level. Peak effect (52.79% reduction; P<0.001) was produced at the dose of 600mg/kg on day 21. In normoglycemic rats, VA (600mg/kg) caused significant reduction (P<0.05) in blood glucose level on days 1 and 21 with 16.38% and 15.63% reductions respectively. In diabetic rats, VA significantly reduced the level of catalase (CAT) and malondialdehyde (MDA) in the kidney, and increased the level of superoxide dismutase, CAT and glutathione peroxidase with reduction in MDA in the liver compared to diabetic control, especially at the dose of 600mg/kg. VA (600mg/kg) generally increased the level of HDL and reduced the levels of TG, LDL, TC, AST, ALT, ALP, bilirubin, creatinine and urea compared with diabetic control. The findings in this study suggest that VA possess beneficial antidiabetic effects. PMID:26015307

  3. Protective Effect of Ethanol Extracts of Hericium erinaceus on Alloxan-Induced Diabetic Neuropathic Pain in Rats.

    PubMed

    Yi, Zhang; Shao-Long, Yang; Ai-Hong, Wang; Zhi-Chun, Sun; Ya-Fen, Zhuo; Ye-Ting, Xu; Yu-Ling, He

    2015-01-01

    We investigated the effects of Hericium erinaceus (HEE) on alloxan induced diabetic neuropathic pain in laboratory rats. Alloxan induced diabetic rats were administered orally HEE. After 6 weeks of treatments, treatment with HEE 40?mg/kg in diabetic animals showed significant increase in pain threshold and paw withdrawal threshold and significant decrease in serum glucose and urine glucose. We also observed a significant increase in lactate dehydrogenase (LDH), Lipid peroxidation (LPO), glutathione peroxidase (GPx) activity, glutathione reductase (GR) activity, catalase (CAT) activity, Na(+)K(+)ATPase activity, and glutathione S transferase (GST) activity along with significant decreased levels of glutathione (GSH) content in diabetic rats. The total antioxidant status (TAOS) in the HEE-treated groups was significantly lower than that in the alloxan-treated group. HEE can offer pain relief in diabetic neuropathic pain. The improvement in diabetic state after HEE treatment along with the antioxidant activity could be the probable way by which it had alleviated diabetic neuropathy. PMID:25960754

  4. Protective Effect of Ethanol Extracts of Hericium erinaceus on Alloxan-Induced Diabetic Neuropathic Pain in Rats

    PubMed Central

    Yi, Zhang; Shao-long, Yang; Ai-hong, Wang; Zhi-chun, Sun; Ya-fen, Zhuo; Ye-ting, Xu; Yu-ling, He

    2015-01-01

    We investigated the effects of Hericium erinaceus (HEE) on alloxan induced diabetic neuropathic pain in laboratory rats. Alloxan induced diabetic rats were administered orally HEE. After 6 weeks of treatments, treatment with HEE 40?mg/kg in diabetic animals showed significant increase in pain threshold and paw withdrawal threshold and significant decrease in serum glucose and urine glucose. We also observed a significant increase in lactate dehydrogenase (LDH), Lipid peroxidation (LPO), glutathione peroxidase (GPx) activity, glutathione reductase (GR) activity, catalase (CAT) activity, Na+K+ATPase activity, and glutathione S transferase (GST) activity along with significant decreased levels of glutathione (GSH) content in diabetic rats. The total antioxidant status (TAOS) in the HEE-treated groups was significantly lower than that in the alloxan-treated group. HEE can offer pain relief in diabetic neuropathic pain. The improvement in diabetic state after HEE treatment along with the antioxidant activity could be the probable way by which it had alleviated diabetic neuropathy. PMID:25960754

  5. Beneficial Effects of Pentanema vestitum Linn. Whole Plant on the Glucose and Other Biochemical Parameters of Alloxan Induced Diabetic Rabbits

    PubMed Central

    Ilahi, Ikram; Asghar, Ali; Ali, Shujat; Khan, Murad; Khan, Nasrullah

    2012-01-01

    The residents of Lower Dir and Malakand agency, Khyber Pakhtunkhwa, Pakistan, use the dry powder of whole plant of Pentanema vestitum for the treatment of asthma and diabetes. No documented reports are available about the therapeutic action of Pentanema vestitum. The present study was aimed to explore the antihyperglycemic effect of 70% methanol extract of Pentanema vestitum whole plant in glucose-induced nondiabetic hyperglycemic and alloxan-induced diabetic rabbits. During this study, the effects of plant extract on the serum lipid profile, GPT, ALP, bilirubin and creatinine of diabetic rabbits were also studied. The extract of Pentanema vestitum whole plant exhibited significant (P < 0.05) antihyperglycemic activity in glucose-induced hyperglycemic rabbits. Treatment of alloxan-induced diabetic rabbits with extract significantly (P < 0.05) reduced the elevated levels of serum glucose, GPT, ALP, bilirubin and creatinine. During the study of lipid profile, the extract proved to be antihyperlipidemic and HDL boosting in diabetic rabbit models. From the finding of the present research, it was concluded that the 70% methanol extract of Pentanema vestitum whole plant has beneficial effects on serum levels of glucose, lipid profile, GPT, ALP, bilirubin, and creatinine of diabetic rabbits. PMID:23316385

  6. Serum glucose and malondialdehyde levels in alloxan induced diabetic rats supplemented with methanolic extract of tacazzea apiculata.

    PubMed

    Gwarzo, M Y; Ahmadu, J H; Ahmad, M B; Dikko, A U A

    2014-12-01

    Tacazzea apiculata is used by traditional medical practitioners for the treatment of wide range of diseases. The current work investigated the hypoglycemic and antioxidant properties of Tacazzea apiculata Oliv. on alloxan induced diabetes mellitus. Five groups (n=10) of rats were fed on commercial diet. The rats were divided into Group 1 (NUT) as non-diabetic and untreated, group 2 (NDT) as non-diabetic and treated, group 3 (DT) diabetic and treated. Group 4 (DUT) as diabetic and untreated. Group five (CP) were diabetic treated with Chlorpropamide, a drug used in the management of diabetic mellitus, with no known antioxidant property. Diabetic induction was done by intra-peritoneal injection of 100 mg/kg b. wt with alloxan. Fasting blood glucose was estimated seven days after induction to determine the severity of glucose elevation among the induced groups. Methanolic extract of T. apiculata leaf was administered to alloxan induced diabetic and non-diabetic control rats at 100mg/kg body weight for four weeks and blood glucose estimated on weekly basis. Malondialdehyde level was also estimated in the sera of the rats. Blood glucose level was monitored for additional 2 weeks post treatment. The results indicated that the extracts possess significant hypoglycemic effect on the diabetic rats (DT) having the mean glucose of (95.2 ± 9.12 mg/dl) compared to the diabetic untreated control group (DUT) with a mean glucose of (238.91 ± 4.42 mg/dl, p<0.05). The effect was sustained even on withdrawal of the extracts for two weeks. This was accompanied by a progressive increase in weight among all treated diabetic rats and non diabetic treated (DT and NDT) compared with diabetic untreated control rat (DUT) (p<0.05). A raised level in malondialdehyde was also observed among the diabetic rat prior to treatment and significantly decreased after the treatment. In conclusion the research demonstrated the hypoglycaemic and antioxidant potential of methanolic leaf extract of T. apiculata in alloxan induced rats. PMID:25598753

  7. Serum Glucose and Malondialdehyde Levels in Alloxan Induced Diabetic Rats Supplemented with Methanolic Extract of Tacazzea Apiculata

    PubMed Central

    Gwarzo, M. Y.; Ahmadu, J. H.; Ahmad, M. B.; Dikko, A. U. A.

    2014-01-01

    Tacazzea apiculata is used by traditional medical practitioners for the treatment of wide range of diseases. The current work investigated the hypoglycemic and antioxidant properties of Tacazzea apiculata Oliv. on alloxan induced diabetes mellitus. Five groups (n=10) of rats were fed on commercial diet. The rats were divided into Group 1 (NUT) as non-diabetic and untreated, group 2 (NDT) as non-diabetic and treated, group 3 (DT) diabetic and treated. Group 4 (DUT) as diabetic and untreated. Group five (CP) were diabetic treated with Chlorpropamide, a drug used in the management of diabetic mellitus, with no known antioxidant property. Diabetic induction was done by intra-peritoneal injection of 100 mg/kg b. wt with alloxan. Fasting blood glucose was estimated seven days after induction to determine the severity of glucose elevation among the induced groups. Methanolic extract of T. apiculata leaf was administered to alloxan induced diabetic and non-diabetic control rats at 100mg/kg body weight for four weeks and blood glucose estimated on weekly basis. Malondialdehyde level was also estimated in the sera of the rats. Blood glucose level was monitored for additional 2 weeks post treatment. The results indicated that the extracts possess significant hypoglycemic effect on the diabetic rats (DT) having the mean glucose of (95.2 ± 9.12 mg/dl) compared to the diabetic untreated control group (DUT) with a mean glucose of (238.91 ± 4.42 mg/dl, p<0.05). The effect was sustained even on withdrawal of the extracts for two weeks. This was accompanied by a progressive increase in weight among all treated diabetic rats and non diabetic treated (DT and NDT) compared with diabetic untreated control rat (DUT) (p<0.05). A raised level in malondialdehyde was also observed among the diabetic rat prior to treatment and significantly decreased after the treatment. In conclusion the research demonstrated the hypoglycaemic and antioxidant potential of methanolic leaf extract of T. apiculata in alloxan induced rats. PMID:25598753

  8. Hypoglycemic and hypolipidemic activity of ethanolic extract of Salvadora oleoides in normal and alloxan-induced diabetic rats

    PubMed Central

    Yadav, J.P.; Saini, Sushila; Kalia, A.N.; Dangi, A.S.

    2008-01-01

    Objective: To find out the hypoglycemic and hypolipidemic activity of an ethanolic extract of the aerial part of Salvadora oleoides Decne in euglycemic and alloxan-induced diabetic albino rats. Materials and Methods: Diabetes was induced in albino rats by administration of alloxan monohydrate (120 mg/kg, i.p.). Normal as well as diabetic albino rats were divided into groups (n = 6) receiving different treatments: vehicle (control), ethanolic extract (1 g and 2 g/kg b.w), and standard antidiabetic drug tolbutamide (0.5 g/kg b.w.). Blood samples were collected by cardiac puncture and were analyzed for blood glucose and lipid profile on days 0, 7, 14, and 21. Results: The ethanolic extract of S oleoides produced significant reduction (P < 0.001) in blood glucose and also had beneficial effects (P < 0.001) on the lipid profile in euglycemic as well as alloxan-induced diabetic rats at the end of the treatment period (21st day). However, the reduction in the blood glucose and improvement in lipid profile was less than that achieved with the standard drug tolbutamide. Conclusion: We concluded that an ethanolic extract of S oleoides is effective in controlling blood glucose levels and improves lipid profile in euglycemic as well as diabetic rats. PMID:21264157

  9. Therapeutic potency of saponin rich aqueous extract of Scoparia dulcis L. in alloxan induced diabetes in rats

    PubMed Central

    Perumal, P. Saravana; Anaswara, P. V.; Muthuraman, A.; Krishan, S.

    2014-01-01

    Background: Diabetes mellitus is major metabolic disorders of carbohydrate metabolism. This leads to alter the multiple organ system. Aims: To investigate the antidiabetic and antioxidant effects of the saponin rich aqueous extract of Scoparia dulcis (SRE-SD) using alloxan-induced hyperglycemic rat model. Material and Methods: The single dose of alloxan was injected for the induction of diabetes in rats. The SRE-SD and glibenclamide were administered for 15 consecutive days from the 3rd day of alloxan administration. Quantity of food and water intake was measured at day 0, and 18. Further, body weight was recorded and blood samples were collected at different time intervals that is, day 0, 3, 8, 13, and 18. The oxidative biomarkers (i.e. thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH) and nitrite (NO2?) levels were also estimated in the serum sample. Results: The SRE-SD showed a remarkable dose and time-dependent changes in alloxan-induced rise in the level of food consumption and water intake, serum glucose level, TBARS, NO2? and fall in the level of GSH. Further, significant attenuation was observed at 20 and 30 mg/kg of SRE-SD treated group. Conclusions: These findings demonstrate that SRE-SD has both antidiabetic and antioxidant effects on the experimental model of diabetes in rat. PMID:25558170

  10. The effects of aqueous extract of alfalfa on blood glucose and lipids in alloxan-induced diabetic rats.

    PubMed

    Amraie, Esmaiel; Farsani, Masome Khosravi; Sadeghi, Leila; Khan, Tayaba Naim; Babadi, Vahid Yousefi; Adavi, Zohrab

    2015-09-01

    Diabetes is a common metabolic disorder that is specified by hyperglycemia resulting from defects in insulin secretion, insulin action, or both. The use of nonpharmacological treatments (herbal agents) is a new approach in the management of diabetes. The aim of this study was to investigate the effect of aqueous extract of alfalfa on blood glucose and serum lipids in alloxan-induced diabetic rats. In this study, 32 female rats (210-250 g) were used which were divided randomly into 4 groups including intact control group, diabetic control group, and 2 diabetic groups which received 250 and 500 mg/kg doses of aqueous extract of alfalfa, respectively. In the diabetic groups, alloxan-monohydrate was injected peritoneally to create diabetic condition. The two last groups orally received aqueous extract of alfalfa for 21 days. At the end of experiment, sugar, cholesterol, triglycerides, high-density and low-density lipoprotein, and aspartate aminotransferase (ALT) and alanine aminotransferase (AST) levels were measured in the samples. Consumption of aqueous alfalfa extract significantly reduced glucose, cholesterol, triglycerides, and low-density lipoprotein (LDL) levels in the diabetic rats but enhanced high-density lipoprotein (HDL) levels. ALT and AST liver enzyme levels were also reduced in blood. Histological examination showed that the aqueous alfalfa extract caused reconstruction of damaged liver and enhanced Langerhans islets' diameter in pancreas. Therefore, all signs of diabetes were improved by oral administration of alfalfa in defined dose. PMID:26525173

  11. Antidiabetic and antihyperlipidaemic activity of ethanol extract of Melastoma malabathricum Linn. leaf in alloxan induced diabetic rats

    PubMed Central

    Balamurugan, Karuppasamy; Nishanthini, Antony; Mohan, Veerabahu Ramasamy

    2014-01-01

    Objective To evaluate the antidiabetic and antihyperlipidaemic effect of ethanol extract of Melastoma malabathricum (M. malabathricum) Linn. leaf in alloxan induced diabetic rats. Methods Diabetes was induced in albino rats by administration of alloxan monohydrate (150 mg/kg i.p). the ethanol extracts of M. malabathricum at a dose of 150 and 300 mg/kg of body weight were administrated at a single dose per day to diabetes induced rats for a period of 14 d. The effect of ethanol extract of M. malabathricum leaf extract on blood glucose, plasma insulin, creatinine, glycosylated haemoglobin, urea serum lipid profile [total cholesterol, triglycerides, low density lipoprotein-cholesterol, very low density lipoprotein-cholesterol, high density lipoprotein-cholesterol and phospholipid, serum protein, albumin, globulin, serum enzymes (serum glutamate pyruvate transaminases), serum glutamate oxaloacetate transaminases, and alkaline phosphatase] were measured in the diabetic rats. Results In the acute toxicity study, ethanol extract of M. malabathricum leaf was non-toxic at 2?000 mg/kg in rats. The increased body weight, decreased blood glucose, glycosylated haemoglobin and other biochemical parameters level were observed in diabetic rats treated with both doses of ethanol extract of M. malabathricum leaf compared to diabetic control rats. In diabetic rats, ethanol extract of M. malabathricum leaf administration, altered lipid profiles were reversed to near normal than diabetic control rats. Conclusions Ethanol extract of M. malabathricum leaf possesses significant antidiabetic and antihyperlipidaemic activity in diabetic rats. PMID:25183126

  12. The effects of aqueous extract of alfalfa on blood glucose and lipids in alloxan-induced diabetic rats

    PubMed Central

    Amraie, Esmaiel; Farsani, Masome Khosravi; Sadeghi, Leila; Khan, Tayaba Naim; Adavi, Zohrab

    2015-01-01

    Diabetes is a common metabolic disorder that is specified by hyperglycemia resulting from defects in insulin secretion, insulin action, or both. The use of nonpharmacological treatments (herbal agents) is a new approach in the management of diabetes. The aim of this study was to investigate the effect of aqueous extract of alfalfa on blood glucose and serum lipids in alloxan-induced diabetic rats. In this study, 32 female rats (210–250 g) were used which were divided randomly into 4 groups including intact control group, diabetic control group, and 2 diabetic groups which received 250 and 500 mg/kg doses of aqueous extract of alfalfa, respectively. In the diabetic groups, alloxan-monohydrate was injected peritoneally to create diabetic condition. The two last groups orally received aqueous extract of alfalfa for 21 days. At the end of experiment, sugar, cholesterol, triglycerides, high-density and low-density lipoprotein, and aspartate aminotransferase (ALT) and alanine aminotransferase (AST) levels were measured in the samples. Consumption of aqueous alfalfa extract significantly reduced glucose, cholesterol, triglycerides, and low-density lipoprotein (LDL) levels in the diabetic rats but enhanced high-density lipoprotein (HDL) levels. ALT and AST liver enzyme levels were also reduced in blood. Histological examination showed that the aqueous alfalfa extract caused reconstruction of damaged liver and enhanced Langerhans islets’ diameter in pancreas. Therefore, all signs of diabetes were improved by oral administration of alfalfa in defined dose. PMID:26525173

  13. Protective Effect of Lavandula stoechas and Rosmarinus officinalis essential oils against reproductive damage and oxidative stress in alloxan-induced diabetic rats.

    PubMed

    Sebai, Hichem; Selmi, Slimen; Rtibi, Kais; Gharbi, Najoua; Sakly, Mohsen

    2015-02-01

    The authors aimed in the present study to assess the protective effect of Rosmarinus officinalis essential oils (ROEO) and Lavandula stoechas essential oils (LSEO) against reproductive damage and oxidative stress in alloxan-induced diabetic male rats. Essential oil samples were obtained from the aerial parts of the plants by hydrodistillation and analyzed by the gas chromatography-mass spectrometry (GC-MS). Rats were divided into four groups: healthy control (HC); diabetic control (DC); healthy+ROEO (H+ROEO), healthy+LSEO (H+LSEO), diabetic+ROEO (D+ROEO), and diabetic+LSEO (D+LSEO). The use of GC-MS allowed to the identification of 15 and 22 compounds in ROEO and LSEO, respectively. In addition, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) test showed that ROEO and LSEO had an important antioxidant capacity. In vivo, we initially found that ROEO and LSEO treatment protected against the decrease in alloxan-induced body weight gain, relative reproductive organ weights, testosterone level, as well as sperm quality decline. On the other hand, we showed that alloxan administration was accompanied by an oxidative stress status assessed by an increase of malondialdehyde (MDA) and hydrogen peroxide (H2O2) levels, as well as a depletion of sulfhydril group content (-SH) and antioxidant enzyme activities as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) in testis, epididymis, and sperm. More importantly, ROEO and LSEO treatment significantly protected against oxidative damage of the male reproductive organ systems in alloxan-induced diabetic rats. These findings suggested that ROEO and LSEO exerted a potential protective effect against alloxan-induced reproductive function damage and oxidative stress in male rat. The beneficial effect of ROEO and LSEO might be related, in part, to their antioxidant properties. PMID:25105335

  14. Evaluation of the Antidiabetic and Antilipaemic Activities of the Hydroalcoholic Extract of Phoenix Dactylifera Palm Leaves and Its Fractions in Alloxan-Induced Diabetic Rats

    PubMed Central

    Mard, Seyyed Ali; Jalalvand, Kowthar; Jafarinejad, Masoumeh; Balochi, Hoda; Naseri, Mohammad Kazem Gharib

    2010-01-01

    Background: The antidiabetic and antilipaemic effects of Phoenix dactylifera leaf extract (PDE) and its fractions were investigated in various rat models. Methods: Diabetes was induced in male Wistar rats by alloxan monohydrate. Diabetic animals were randomly divided into 8 groups (1 diabetic control and 7 treated groups). Diabetic control animals received saline (5 mL/kg) orally, whereas the treatment groups received different doses of PDE (100, 200, and 400 mg/kg), PDE fractions (50, 100, and 200 mg/kg), or glibenclamide (4 mg/kg) orally once a day for 14 days. Blood was withdrawn for glucose determination on the 1st, 6th, 10th, and 14th days. The rats were fasted overnight and then sacrificed on the 14th day; blood was collected for biochemical evaluation, including the levels of blood glucose, plasma insulin, serum triglyceride, and cholesterol. Results: Subacute administration of PDE or its fractions in alloxan-induced diabetic rats significantly reduced blood glucose (P < 0.01). Water intake, serum triglyceride, and cholesterol also decreased in treated animals compared with the control group (P < 0.01). Plasma insulin level increased in the treated groups relative to the control group (P < 0.01). Conclusion: The results suggested that PDE exhibits antidiabetic and antilipaemic effects in alloxan-induced diabetic rats. PMID:22135555

  15. Antidiabetic effect of hydroalcoholic extract of Carthamus tinctorius L. in alloxan-induced diabetic rats

    PubMed Central

    Asgary, Sedigheh; Rahimi, Parivash; Mahzouni, Parvin; Madani, Hossein

    2012-01-01

    Background: Carthamus tinctorius L. (Compositae) has been used in Iranian traditional medicine for treatment of diabetes. In this study, anti-diabetic effect of its hydroalcoholic extract was compared with that of glibenclamide. Methods: Male white Wistar rats were randomly allocated into four groups of six each: nondiabetic control; diabetic control; diabetic treated with hydroalcoholic extract of Carthamus tinctorius (200 mg kg-1 BW); diabetic rats treated with glibenclamide (0.6 mg kg-1 BW). Alloxan was administered (120 mg kg-1 BW), intraperitoneally to induce diabetes. Fasting blood samples were collected three times, before injection of alloxan, two weeks and six weeks after injection of alloxan and fasting blood sugar (FBS), Hb A1C, insulin, cholesterol, LDL-C, HDL-C, VLDL-C, triglyceride, alkaline phosphatase (ALP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured each time. Results: FBS, triglyceride, cholesterol, LDL-C and VLDL-C had a meaningful decrease in diabetic rats treated with Carthamus tinctorius and diabetic rats treated with glibenclamide as compared with diabetic rats with no treatment. Insulin level increased significantly in diabetic groups received treatment (glibenclamide or Carthamus tinctorius L) in comparison with diabetic group with no treatment. The histological study revealed size of islets of Langerhans enlarged significantly consequentially as compared with diabetic rats with no treatment. The extract appeared non toxic as evidenced by normal levels of AST, ALP and ALT. Effects of administrating glibenclamide or extract of Carthamus tinctorius L on all biochemical parameters discussed above showed no difference and both tend to bring the values to near normal. Conclusion: These results suggested that the hydroalcoholic extract of Carthamus tinctorius possesses beneficial effect on treatment of diabetes. PMID:23267403

  16. Coconut kernel-derived proteins enhance hypolipidemic and antioxidant activity in alloxan-induced diabetic rats.

    PubMed

    Salil, Gopalakrishnan; Nevin, Kottayath Govindan; Rajamohan, Thankappan

    2013-05-01

    Impaired lipid levels and oxidative stress are indicative of malfunction of endogenous antioxidant capacity. The aim of this study was to determine the effect of coconut kernel protein (CKP) on the lipid peroxides and antioxidant enzyme activities in diabetic rats. Diabetes was induced prior to feeding by injecting a single dose of alloxan (150 mg/kg body weight) intraperitoneally. CKP (8% w/w) was administered to these rats along with a semi-synthetic diet for 45 days. After the experimental period, peroxide products and antioxidant enzyme activities were determined. Results show that CKP maintained the antioxidant enzyme activities and levels of peroxides to the normal levels in treated group compared to diabetic rats. This study clearly show that CKP has potential effect in lowering oxidative stress associated with diabetes. This beneficial effect of CKP may be due to the high amount of biologically potent arginine present in it. PMID:23113582

  17. Alloxan-Induced Diabetes Causes Morphological and Ultrastructural Changes in Rat Liver that Resemble the Natural History of Chronic Fatty Liver Disease in Humans

    PubMed Central

    Cassettari, Lucas Langoni; Spadella, César Tadeu

    2015-01-01

    Purpose. This study evaluated the long-term effects of alloxan-induced diabetes in rat liver. Methods. Thirty nondiabetic control rats (NC) and 30 untreated diabetic (UD) rats were divided into three subgroups sacrificed after 6, 14, or 26 weeks. Clinical and laboratory parameters were assessed. Fresh liver weight and its relationship with body weight were obtained, and liver tissue was analyzed. Results. UD rats showed sustained hyperglycemia, high glycosylated hemoglobin, and low plasma insulin. High serum levels of AST and ALT were observed in UD rats after 2 weeks, but only ALT remained elevated throughout the experiment. Fresh liver weight was equal between NC and UD rats, but the fresh liver weight/body weight ratio was significantly higher in UD rats after 14 and 26 weeks. UD rats showed liver morphological changes characterized by hepatic sinusoidal enlargement and micro- and macrovesicular hepatocyte fatty degeneration with progressive liver structure loss, steatohepatitis, and periportal fibrosis. Ultrastructural changes of hepatocytes, such as a decrease in the number of intracytoplasmic organelles and degeneration of mitochondria, rough endoplasmic reticulum, and nuclei, were also observed. Conclusion. Alloxan-induced diabetes triggered liver morphological and ultrastructural changes that closely resembled human disease, ranging from steatosis to steatohepatitis and liver fibrosis. PMID:25789328

  18. Additive effect of lipid lowering drug (simvastatin) in combination with antidiabetic drug (glibenclamide) on alloxan induced diabetic rats with long term dyslipidemia.

    PubMed

    Begum, Mst Marium; Sultana, Zakia; Ershad Ali, Md; Jami, Md Safkath Ibne; Khondkar, Proma; Khan, Md Masuduzzaman; Haque, Md Mominul

    2014-10-01

    High blood glucose level, elevated level of liver enzyme, necrosis and shrinkage of islets of Langerhans has been implicated in the pathogenesis of type 2 diabetes. High blood glucose cause oxidative stress, production of free radical as well as elevated SGPT and SGOT level. Both glibenclamide and simvastatin in fixed dose used as antihyperglycemic antidyslipidemic and antioxidative agents for type 2 diabetes treatment. This study therefore aimed to evaluate the antihyperglycemic, antidyslipidemic and antioxidative effect of fixed dose combination of glibenclamide (0.6 mg/70 kg body weight) and simvastatin (5 mg/70 kg body weight) on long term alloxan induced diabetic rats with cardiovascular disease using various diagnostic kits as a parameter of phamacotherapeutic and pharmacological effect. The study was carried out using 96 Swiss Albino male rats weighing about 200-220 g. Combination therapy induced a significant decrease in blood glucose level in alloxan induced diabetic rats, from 33.75 ± 1.65 to 5.80 ± 0.07 mmol/l 2 h after last dose administration, after 4 weeks treatment. In case of dyslipidemic effect, combination therapy reduced total cholesterol (45 %), triglyceride (36 %) and low density lipoprotein-cholesterol (32 %) levels significantly and increased high density lipoprotein-cholesterol level (57 %) in comparison with their respective diabetic control groups. Results of this study showed that combination therapy effectively decreased SGPT (ALAT) (55 %) and SGOT (ASAT) (51 %) in comparison with diabetic control group. It was also observed that catalase and superoxide dismutase enzyme activity was increased by 58 and 91 % respectively in comparison with diabetic control group after 4 weeks treatment with combination of both drugs. In conclusion, these findings of combination therapy (glibenclamide and simvastatin) on alloxan induced diabetes in rats are significantly better than monotherapy using single drug. The results of the present study suggest that, combination of the fixed dose of glibenclamide and simvastatin might be efficacious in patients with diabetic dyslipidemia and increased oxidative stress. Furthermore, this combination therapy offer dosage convenience to the patients and by virtue of its dual mode of action might be a useful addition to the therapeutic armamentarium for patients with diabetic dyslipidemia and oxidative stress. PMID:25298626

  19. Hypoglycemic and antilipidemic properties of kombucha tea in alloxan-induced diabetic rats

    PubMed Central

    2012-01-01

    Background Diabetes has become a serious health problem and a major risk factor associated with troublesome health complications, such as metabolism disorders and liver-kidney dysfunctions. The inadequacies associated with conventional medicines have led to a determined search for alternative natural therapeutic agents. The present study aimed to investigate and compare the hypoglycemic and antilipidemic effects of kombucha and black tea, two natural drinks commonly consumed around the world, in surviving diabetic rats. Methods Alloxan diabetic rats were orally supplied with kombucha and black tea at a dose of 5 mL/kg body weight per day for 30 days, fasted overnight, and sacrificed on the 31st day of the experiment. Their bloods were collected and submitted to various biochemical measurements, including blood glucose, cholesterol, triglcerides, urea, creatinine, transaminases, transpeptidase, lipase, and amylase activities. Their pancreases were isolated and processed to measure lipase and ?-amylase activities and to perform histological analysis. Results The findings revealed that, compared to black tea, kombucha tea was a better inhibitor of ?-amylase and lipase activities in the plasma and pancreas and a better suppressor of increased blood glucose levels. Interestingly, kombucha was noted to induce a marked delay in the absorption of LDL-cholesterol and triglycerides and a significant increase in HDL-cholesterol. Histological analyses also showed that it exerted an ameliorative action on the pancreases and efficiently protected the liver-kidney functions of diabetic rats, evidenced by significant decreases in aspartate transaminase, alanine transaminase, and gamma-glytamyl transpeptidase activities in the plasma, as well as in the creatinine and urea contents. Conclusions The findings revealed that kombucha tea administration induced attractive curative effects on diabetic rats, particularly in terms of liver-kidney functions. Kombucha tea can, therefore, be considered as a potential strong candidate for future application as a functional supplement for the treatment and prevention of diabetes. PMID:22591682

  20. Effect of 50% Hydro-Ethanolic Leaf Extracts of Ruellia Tuberosa L. and Dipteracanthus Patulus (Jacq.) on Lipid Profile in Alloxan Induced Diabetic Rats

    PubMed Central

    Ananthakrishnan, Manikandan; Doss, Victor Arokia

    2013-01-01

    Background: The study was undertaken to investigate the effect of 50% hydro -ethanolic leaf extracts of Ruellia tuberosa L. and Dipteracanthus patulus (Jacq.) on lipid profile in alloxan induced diabetic rats. Method: In lipid profile the parameters studied were serum total cholesterol, phospholipids, triglycerides, HDL-c, LDL-c and VLDL-c level. Extracts were orally administered daily for 30 days at a dosage of 250 and 500 mg/kg bodyweight to alloxan induced diabetic rats. Results: The levels of phospholipids, triglycerides, LDL-c and VLDL-c were significantly (P < 0.05) reduced. The HDL-c level was found to be increased in the treatment groups. Total cholesterol level was found to be significantly (P < 0.05) decreased at 500 mg/kg bodyweight of both the plant extracts treated groups. Conclusion: The results further suggests that the effect of plant extract treated groups was found to be lower in reducing the lipid levels in serum when compared to the drug (Glibenclamide 600 ?g/kg body weight) treated group. PMID:24049591

  1. Hypoglycemic activity of Nymphaea stellata leaves ethanolic extract in alloxan induced diabetic rats.

    PubMed

    Dhanabal, S P; Raja, M K Mohan Maruga; Ramanathan, M; Suresh, B

    2007-06-01

    The ethanolic extract of leaves of Nymphaea stellata given by oral route to diabetic rats at dose of 100 and 200 mg/kg/day for seven days reduced significantly by 31.6 and 42.6 % the plasma glucose level increased by intraperitoneal injection of 120 mg/day of alloxan. Moreover, the treatment significantly affected the plasma level of cholesterol and triglyceride. PMID:17498889

  2. Antihyperglycemic activity of Tectona grandis Linn. bark extract on alloxan induced diabetes in rats

    PubMed Central

    Varma, S. B.; Jaybhaye, D. L.

    2010-01-01

    Tectona Grandis Linn.(saag - tick wood), an indigenous medicinal plant, has a folk reputation among the Indian herbs as a hypoglycemic agent. The present study was carried out to evaluate the anti-hyperglycemic effect of T. grandis Linn. bark extract in control and alloxan-diabetic rats. Oral administration of the bark suspension of T. grandis (2.5 and 5 g/kg body wt.) for 30 days resulted in a significant reduction in blood glucose (from 250 ± 6.5 to 50 ± 2.5 mg/dL). Thus, the present study clearly shows that the T. grandis Linn. bark extract exerts anti-hyperglycemic activity. PMID:21170208

  3. Study of Antiglycation, Hypoglycemic, and Nephroprotective Activities of the Green Dwarf Variety Coconut Water (Cocos nucifera L.) in Alloxan-Induced Diabetic Rats.

    PubMed

    Pinto, Isabella F D; Silva, Railmara P; Chaves Filho, Adriano de B; Dantas, Lucas S; Bispo, Vanderson S; Matos, Isaac A; Otsuka, Felipe A M; Santos, Aline C; Matos, Humberto Reis

    2015-07-01

    Coconut water (CW) is a natural nutritious beverage, which contains several biologically active compounds that are traditionally used in the treatment of diarrhea and rehydration. Several works with CW have been related with antioxidant activity, which is very important in the diabetic state. To evaluate the hypoglycemic and nephroprotective activities of CW, alloxan-induced diabetic rats were pre- and post-treated by gavage with CW (3?mL/kg), caffeic acid (CA) (10 and 15?mg/kg), and acarbose (Acb) (714 ?g/kg) during a period of 16 days. Body weight, blood glucose, glycated hemoglobin (HbA1c), and Amadori products in plasma and kidney homogenates were evaluated in all groups and used as parameters for the monitoring of the diabetic state. The results showed that rats of the CW+diabetic group had maintenance in blood glucose compared with the control group (P<.05) in addition to a decrease of HbA1c levels and increase of body weight when compared with the diabetic group rats (P<.05). The animals of the CA and CA+diabetic groups did not have significant variation of body weight (P<.05) during the experiment; however, they showed decrease in their HbA1c and urea levels in plasma as well as Amadori products in kidney homogenates when compared with the diabetic group (P<.05). Our results indicate that CW has multiple beneficial effects in diabetic rats for preventing hyperglycemia and oxidative stress caused by alloxan. PMID:25651375

  4. Investigation of the Protective Effects of Taurine against Alloxan-Induced Diabetic Retinal Changes via Electroretinogram and Retinal Histology with New Zealand White Rabbits

    PubMed Central

    Yeh, Shang-Min; Chen, Yi-Chen; Lin, Shiun-Long

    2014-01-01

    The purpose of this study was to investigate the protective role of orally administered taurine against diabetic retinal changes via electroretinogram (ERG) and retinal histology on rabbits. Rabbits were randomly assigned into groups: Group I (vehicle administration only); Group II (diabetes: induced by 100?mg/kg alloxan injection); Group III (diabetes and fed with 200?mg/kg taurine); and Group IV (diabetes and fed with 400?mg/kg taurine). The body weight and blood glucose levels of the rabbits were monitored weekly. The ERG was measured on weeks 5 and 15. Retinal histology was analyzed in the end of the experiment. Results revealed that a taurine supplement significantly ameliorates the alloxan-induced hyperglycemia and protects the retina from electrophysiological changes. Group II showed a significant (P < 0.05) change in the mean scotopic b-wave amplitude when compared to that of Group I, whereas the diabetic rabbits treated with taurine (Group III and IV) were analogous to Group I. Histologically, the amount of Bipolar and Müller cells showed no difference (P > 0.05) between all groups and when compared with those of Group I. Our study provides solid evidences that taurine possesses an antidiabetic activity, reduced loss of body weight, and less electrophysiological changes of the diabetic retina. PMID:25298779

  5. Moringa oleifera leaf extract ameliorates alloxan-induced diabetes in rats by regeneration of ? cells and reduction of pyruvate carboxylase expression.

    PubMed

    Abd El Latif, Amira; El Bialy, Badr El Said; Mahboub, Hamada Dahi; Abd Eldaim, Mabrouk Attia

    2014-10-01

    Moringa oleifera Lam. contains many active ingredients with nutritional and medicinal values. It is commonly used in folk medicine as an antidiabetic agent. The present study was designed to investigate how an aqueous extract from the leaves of M. oleifera reveals hypoglycemia in diabetic rats. M. oleifera leaf extract counteracted the alloxan-induced diabetic effects in rats as it normalized the elevated serum levels of glucose, triglycerides, cholesterol, and malondialdehyde, and normalized mRNA expression of the gluconeogenic enzyme pyruvate carboxylase in hepatic tissues. It also increased live body weight gain and normalized the reduced mRNA expression of fatty acid synthase in the liver of diabetic rats. Moreover, it restored the normal histological structure of the liver and pancreas damaged by alloxan in diabetic rats. This study revealed that the aqueous extract of M. oleifera leaves possesses potent hypoglycemic effects through the normalization of elevated hepatic pyruvate carboxylase enzyme and regeneration of damaged hepatocytes and pancreatic ? cells via its antioxidant properties. PMID:25289966

  6. Antidiabetic activity of medium-polar extract from the leaves of Stevia rebaudiana Bert. (Bertoni) on alloxan-induced diabetic rats

    PubMed Central

    Misra, Himanshu; Soni, Manish; Silawat, Narendra; Mehta, Darshana; Mehta, B. K.; Jain, D. C.

    2011-01-01

    Objective: To investigate the medicative effects of medium-polar (benzene:acetone, 1:1, v/v) extract of leaves from Stevia rebaudiana (family Asteraceae) on alloxan-induced diabetic rats. Materials and Methods: Diabetes was induced in adult albino Wistar rats by intraperitoneal (i.p.) injection of alloxan (180 mg/kg). Medium-polar extract was administered orally at daily dose of 200 and 400 mg/kg body wt. basis for 10 days. The control group received normal saline (0.9%) for the same duration. Glibenclamide was used as positive control reference drug against Stevia extract. Results: Medium-polar leaf extract of S. rebaudiana (200 and 400 mg/kg) produced a delayed but significant (P < 0.01) decrease in the blood glucose level, without producing condition of hypoglycemia after treatment, together with lesser loss in the body weight as compared with standard positive control drug glibenclamide. Conclusions: Treatment of diabetes with sulfonylurea drugs (glibenclamide) causes hypoglycemia followed by greater reduction in body weight, which are the most worrisome effects of these drugs. Stevia extract was found to antagonize the necrotic action of alloxan and thus had a re-vitalizing effect on ?-cells of pancreas. PMID:21687353

  7. Anion Gap Toxicity in Alloxan Induced Type 2 Diabetic Rats Treated with Antidiabetic Noncytotoxic Bioactive Compounds of Ethanolic Extract of Moringa oleifera

    PubMed Central

    2014-01-01

    Moringa oleifera (MO) is used for a number of therapeutic purposes. This raises the question of safety and possible toxicity. The objective of the study was to ascertain the safety and possible metabolic toxicity in comparison with metformin, a known drug associated with acidosis. Animals confirmed with diabetes were grouped into 2 groups. The control group only received oral dose of PBS while the test group was treated with ethanolic extract of MO orally twice daily for 5-6 days. Data showed that the extract significantly lowered glucose level to normal values and did not cause any significant cytotoxicity compared to the control group (P = 0.0698); there was no gain in weight between the MO treated and the control groups (P > 0.8115). However, data showed that treatment with an ethanolic extract of MO caused a decrease in bicarbonate (P < 0.0001), and more than twofold increase in anion gap (P < 0.0001); metformin treatment also decreased bicarbonate (P < 0.0001) and resulted in a threefold increase in anion gap (P < 0.0001). Conclusively, these data show that while MO appears to have antidiabetic and noncytotoxic properties, it is associated with statistically significant anion gap acidosis in alloxan induced type 2 diabetic rats. PMID:25548560

  8. Comparative Effects of Some Medicinal Plants: Anacardium occidentale, Eucalyptus globulus, Psidium guajava, and Xylopia aethiopica Extracts in Alloxan-Induced Diabetic Male Wistar Albino Rats

    PubMed Central

    Okpashi, Victor Eshu; Bayim, Bayim Peter-Robins; Obi-Abang, Margaret

    2014-01-01

    Insulin therapy and oral antidiabetic agents/drugs used in the treatment of diabetes mellitus have not sufficiently proven to control hyperlipidemia, which is commonly associated with the diabetes mellitus. Again the hopes that traditional medicine and natural plants seem to trigger researchers in this area is yet to be discovered. This research was designed to compare the biochemical effects of some medicinal plants in alloxan-induced diabetic male Wistar rats using named plants that are best at lowering blood glucose and hyperlipidemia and ameliorating other complications of diabetes mellitus by methods of combined therapy. The results obtained showed 82% decrease in blood glucose concentration after the 10th hour to the fortieth hour. There was significant increase P < 0.05 in the superoxide dismutase activity of the test group administered 100?mg/kg of A. Occidentale. There was no significant difference P > 0.05 recorded in the glutathione peroxidase activity of E. globulus (100?mg/kg) when compared to the test groups of P. guajava (250?mg/kg) and X. aethiopica (250?mg/kg). Catalase activity showed significant increase P < 0.05 in the catalase activity, compared to test groups. While at P > 0.05, there was no significant difference seen between test group and treated groups. Meanwhile, degree of significance was observed in other parameters analysed. The biochemical analysis conducted in this study showed positive result, attesting to facts from previous works. Though these individual plants extracts exhibited significant increase in amelorating diabetes complication and blood glucose control compared to glibenclamide, a synthetic antidiabetic drug. Greater performance was observed in the synergy groups. Therefore, a poly/combined formulation of these plants extracts yielded significant result as well as resolving some other complications associated with diabetics. PMID:25525518

  9. Anti-diabetic properties of flavonoid compounds isolated from Hyphaene thebaica epicarp on alloxan induced diabetic rats

    PubMed Central

    Salib, Josline Y.; Michael, Helana N.; Eskande, Emad Fawzy

    2013-01-01

    Background: Diabetes mellitus, becoming the third killer of mankind after cancer and cardiovascular diseases, is one of the most challenging diseases facing health care professionals today. That is why; there has been a growing interest in the therapeutic use of natural products for diabetes, especially those derived from plants. Aim: To evaluate the anti-diabetic activity together with the accompanying biological effects of the fractions and the new natural compounds of Hyphaene thebaica (HT) epicarp. Materials and Methods: 500 g of coarsely powdered of (HT) fruits epicarp were extracted by acetone. The acetone crude extract was fractionated with methanol and ethyl acetate leaving a residual water-soluble fraction WF. The anti-diabetic effects of the WF and one of its compounds of the acetone extract of the (HT) epicarp were investigated in this study using 40 adult male rats. Results: Phytochemical investigation of active WF revealed the presence of ten different flavonoids, among which two new natural compounds luteolin 7-O-[6”-O-?-Lrhamnopyranosyl]-?-D-galactopyranoside 3 and chrysoeriol 7-O-?-D-galactopyranosyl(1?2)-?-L-arabinofuranoside 5 were isolated. Supplementation of the WF improved glucose and insulin tolerance and significantly lowered blood glycosylated hemoglobin levels. On the other hand, compound 5 significantly reduced AST and ALT levels of liver, respectively. Likewise, the kidney functions were improved for both WF and compound 5, whereby both urea and creatinine levels in serum were highly significant Conclusion: The results justify the use of WF and compound 5 of the (HT) epicarp as anti-diabetic agent, taking into consideration that the contents of WF were mainly flavonoids PMID:23598921

  10. Effect of Croatian propolis on diabetic nephropathy and liver toxicity in mice

    PubMed Central

    2012-01-01

    Background In the present study, we examined the antioxidant effect of water soluble derivative of propolis (WSDP) and ethanolic (EEP) extract of propolis on renal and liver function in alloxan-induced diabetic mice. In addition, we examined whether different extract of propolis could prevent diabetic nephropathy and liver toxicity by inhibiting lipid peroxidation in vivo. Methods Diabetes was induced in Swiss albino mice with a single intravenous injection of alloxan (75?mg?kg-1). Two days after alloxan injection, propolis preparations (50?mg?kg-1 per day) were given intraperitoneally for 7?days in diabetic mice. Survival analysis and body weights as well as hematological and biochemical parameters were measured. The renal and liver oxidative stress marker malonaldehyde levels and histopathological changes were monitored in the liver and kidney of treated and control mice. Results Administration of propolis to diabetic mice resulted in a significant increase of body weight, haematological and immunological parameters of blood as well as 100% survival of diabetic mice. Alloxan-injected mice showed a marked increase in oxidative stress in liver and kidney homogenate, as determined by lipid peroxidation. Histopathological observation of the liver sections of alloxan-induced diabetic mice showed several lesions including cellular vacuolization, cytoplasmic eosinophilia and lymphocyte infiltrations, but with individual variability.Treatment of diabetic mice with propolis extracts results in decreased number of vacuolized cells and degree of vacuolization; propolis treatment improve the impairment of fatty acid metabolism in diabetes. Renal histology showed corpuscular, tubular and interstitial changes in alloxan-induced diabetic mice. Test components did not improve renal histopathology in diabetic mice. Conclusions Propolis preparations are able to attenuate diabetic hepatorenal damage, probably through its anti-oxidative action and its detoxification proccess as well as the potential to minimize the deleterious effects of free radicals on tissue. The protective role of propolis against the ROS induced damages in diabetic mice gives a hope that they may have similar protective action in humans. PMID:22866906

  11. Hypoglycaemic effects of methanolic extract of Canscora decussata (Schult) whole-plant in normal and alloxan-induced diabetic rabbits.

    PubMed

    Irshad, Nadeem; Akhtar, Muhammad Shoaib; Bashir, Sajid; Hussain, Azhar; Shafiq, Muhammad; Iqbal, Javeid; Malik, Abdul

    2015-01-01

    In present study hypoglycaemic effects of the crude powdered C. decussata and its methanolic extract (ME) in alloxan diabetic rabbits were evaluated. The hypoglycaemic effect was measured by blood glucose, insulin level, HbA1c and his to pathology of pancreas. Glucose lowering effect of the ME was studied in diabetic rabbits. The effects of extract on blood glucose, body weight, food in take, fluid intake, OGTT were also evaluated. The results showed that 0.5,1 and 2g/kg of the powder significantly decreased blood glucose levels in normal rabbits and diabetic rabbits at the intervals checked. Oral intake of pioglitazone also reduced the levels in these rabbits. Synergistic hypoglycaemic effect of 600mg/kg of ME with different doses of insulin (2 & 3unit/kg, s/c) further reduced blood glucose levels of treated alloxan-diabetic rabbits. The oral glucose tolerance test revealed lowered area under curve values in ME treated rabbits. Treatment with ME (400 and 600 mg/kg) for 30 days showed highly significant decrease in blood glucose level by augmenting insulin secretion, HbA1cand significant increase in body weight, serum insulin levels in treated diabetic rabbits. Histopathology study showed regeneration of ?-cells. These studies have, therefore, supported the traditional use of this herb in diabetic patients. PMID:25553693

  12. Safety and efficacy of hydroalcoholic extract from Lawsonia inermis leaves on lipid profile in alloxan-induced diabetic rats

    PubMed Central

    Singh, Surender; Verma, Nishikant; Karwasra, Ritu; Kalra, Prerna; Kumar, Rohit; Gupta, Yogendra Kumar

    2015-01-01

    Introduction: Dyslipidemia is one of the most common risk factor for cardiac-related disorders in diabetes mellitus. Diabetic dyslipidemia is characterized by hypertriglyceridemia, low high density lipoprotein and elevated low density lipoprotein concentration. Aim: To explore the effect of Lawsonia inermis hydroalcoholic extract (LIHE) for diabetic dyslipidemic activity along with its safety profile. Materials and Methods: LIHE administered at doses of 100, 200 and 400 mg/kg in rats after induction of hyperglycemia by alloxan. Insulin (1 IU/kg), glibenclamide (2.5 mg/kg), and metformin (100 mg/kg) were used as positive control and 1% gum acacia as normal control. Statistical analysis was performed using one-way analysis of variance, followed by Dunnett's t-test. Results: The percentage reduction in blood glucose level of LIHE at dose of 400 mg/kg was 39.08% on day 21 when compared to baseline (day 0), which is comparable to glibenclamide (44.77%) and metformin (46.30%). Decrease in blood glucose level exhibited significant improvement in lipid profile, plasma albumin, total plasma protein and serum creatinine. Conclusion: Results of this study demonstrated that LIHE significantly improved lipid and lipoprotein pattern observed in diabetic rats and this could be due to improvement in insulin secretion or action, thus has potential to be used in treatment of diabetes mellitus associated dyslipidemia.

  13. Comprehensive Evaluation of Anti-hyperglycemic Activity of Fractionated Momordica charantia Seed Extract in Alloxan-Induced Diabetic Rats

    PubMed Central

    Choudhary, Shailesh Kumar; Chhabra, Gagan; Sharma, Dipali; Vashishta, Aruna; Ohri, Sujata; Dixit, Aparna

    2012-01-01

    The present study evaluates anti-hyperglycemic activity of fractionated Momordica charantia (bitter gourd) seed extracts. Fasting blood glucose levels were evaluated before and after administration of different fractions of the seed extract. Among the three fractions tested, fraction Mc-3 (15?mg/kg b.wt.) showed the maximum anti-hyperglycemic activity and reduced blood glucose levels in experimental diabetic rats significantly. The activities of the key regulatory enzymes of glucose metabolism (hexokinase, pyruvate kinase, lactate dehydrogenase, and glucose-6-phosphate dehydrogenase) were determined in Mc-3-treated diabetic animals. Once-daily administration of the fraction Mc-3 for prolonged period of 18 days to the experimental diabetic animals did not result in any nephrotoxicity or hepatotoxicity as evident from insignificant changes in biochemical parameters indicative of liver and kidney functions. Further fractionation of the fraction Mc-3 by size exclusion chromatography resulted in a fraction, designated Mc-3.2, possessing anti-hyperglycemic activity. The fraction Mc-3.2 showed the presence of a predominant protein band of ~11?kDa on SDS-PAGE. Loss in anti-hyperglycemic activity of the Mc-3.2 upon protease treatment indicates the proteinaceous nature of the anti-hyperglycemic principles. Overall, the results suggest that Momordica charantia seeds contain an effective anti-hyperglycemic protein(s) which may find application in treatment of diabetes without evident toxic effects. PMID:23320026

  14. Effect of Kombucha, a fermented black tea in attenuating oxidative stress mediated tissue damage in alloxan induced diabetic rats.

    PubMed

    Bhattacharya, Semantee; Gachhui, Ratan; Sil, Parames C

    2013-10-01

    Diabetic complications associated with increased oxidative stress can be suppressed by antioxidants. In the present study we investigated the antidiabetic and antioxidant effects of Kombucha (KT), a fermented black tea, in comparison to that of unfermented black tea (BT), in ALX-induced diabetic rats. ALX exposure lowered the body weight and plasma insulin by about 28.12% and 61.34% respectively and elevated blood glucose level and glycated Hb by about 3.79 and 3.73 folds respectively. The oxidative stress related parameters like lipid peroxidation end products (increased by 3.38, 1.7, 1.65, 1.94 folds respectively), protein carbonyl content (increased by 2.5, 2.35, 1.8, 3.26 folds respectively), glutathione content (decreased by 59.8%, 47.27%, 53.69%, 74.03% respectively), antioxidant enzyme activities were also altered in the pancreatic, hepatic, renal and cardiac tissues of diabetic animals. Results showed significant antidiabetic potential of the fermented beverage (150 mg lyophilized extract/kg bw for 14 days) as it effectively restored ALX-induced pathophysiological changes. Moreover, it could ameliorate DNA fragmentation and caspase-3 activation in the pancreatic tissue of diabetic rats. Although unfermented black tea is effective in the above pathophysiology, KT was found to be more efficient. This might be due to the formation of some antioxidant molecules during fermentation period. PMID:23907022

  15. Hypoglycemic and antioxidant effects of leaf essential oil of Pelargonium graveolens L’Hér. in alloxan induced diabetic rats

    PubMed Central

    2012-01-01

    Background Rose-scented geranium (Pelargonium graveolens L’Hér.), which is used in traditional Tunisian folk medicine for the treatment of hyperglycaemia, is widely known as one of the medicinal herbs with the highest antioxidant activity. The present paper is conducted to test the hypoglycemic and antioxidative activities of the leaf essential oil of P. graveolens. Methods The essential oil P. graveolens was administered daily and orally to the rats at two doses of 75?mg/kg and 150?mg/kg body weight (b.w.) for 30?days. The chemical composition of P. graveolens essential oil, body weight, serum glucose, hepatic glycogen, thiobarbituric acid-reactive substances (TBARS), the components of hepatic, and renal and serum antioxidant systems were evaluated. The hypoglycemic effect of rose-scented geranium was compared to that of the known anti-diabetic drug glibenclamide (600??g/kg b.w.). Results After the administration of two doses of essential oil of Pelargonium graveolens L’Hér. together with glibenclamide which is known by its antidiabetic activities and used as reference (600??g/kg b.w.), for four weeks, the serum glucose significantly decreased and antioxidant perturbations were restored. The hypoglycemic effect of P. graveolens at the dose of 150?mg/kg b.w. was significantly (pdiabetic rats that these beneficial effects of geranium oils were confirmed. Conclusions It suggests that administration of essential oil of P. graveolens may be helpful in the prevention of diabetic complications associated with oxidative stress. Our results, therefore, suggest that the rose-scented geranium could be used as a safe alternative antihyperglycemic drug for diabetic patients. PMID:22734822

  16. [Platelet hyperreactivity and antiaggregatory properties of nootropic drugs under conditions of alloxan-induced diabetes in rats].

    PubMed

    Zhiliuk, V I; Levykh, A É; Mamchur, V I

    2012-01-01

    The effects of nootropic drugs (noopept, pentoxifylline, piracetam, pramiracetam, Ginkgo biloba extract, entrop, cerebrocurin and citicoline) on platelet aggregation in rats with experimental diabetes have been studied. It is established that all these drugs exhibit an inhibitory action of various degrees against platelet hyperreactivity under conditions of chronic hyperglycemia. The maximum universality of the antiaggregatory action is characteristic of pramiracetam, entrop and Ginkgo biloba extract. PMID:22702111

  17. Antidiabetic activity and phytochemical screening of crude extract of Stevia rebaudiana in alloxan-induced diabetic rats

    PubMed Central

    Kujur, R. S.; Singh, Vishakha; Ram, Mahendra; Yadava, Harlokesh Narayan; Singh, K. K.; Kumari, Suruchi; Roy, B. K.

    2010-01-01

    Background: Stevia rebaudiana regulates blood sugar, prevents hypertension and tooth decay. Other studies have shown that it has antibacterial as well as antiviral property. Methods: Preliminary phytochemical screening of aqueous, ether and methanolic extracts of S. rebaudiana was done. Acute and sub-acute toxicity were conducted on twenty four Albino rats, divided into one control (Group I) and three treatment groups viz. aqueous extract (Group II), ether extract (Group III) and methanolic extract (Group IV). For the study of antidiabetic effect of S. rebaudiana rats were divided into seven groups (n=6). Diabetes was induced by a single dose of 5% alloxan monohydrate (125 mg/kg, i.p.) after 24 hour fasting.Blood samples were analysed on day 0, 1, 5, 7, 14 and 28. Results: Phytochemical tests showed presence of different kinds of phyto-constituents in aqueous, ether and methanol extract of Stevia rebaudiana leaves. Daily single dose (2.0 g/kg) administration of aqueous extract (A.E.) , ether extract (E.E.) and methanol extract (M.E.) for 28 days of S. rebaudiana could not show any significant change in ALT and AST levels in rats. Blood sugar level was found to be decreased on day 28 in groups of rats treated with A.E., E.E. and M.E. of S. rebaudiana. Conclusion: The extracts of Stevioside rebaudiana could decrease the blood glucose level in diabetic rats in time dependent manner. PMID:21808578

  18. Efficacy of Composite Extract from Leaves and Fruits of Medicinal Plants Used in Traditional Diabetic Therapy against Oxidative Stress in Alloxan-Induced Diabetic Rats

    PubMed Central

    Kumar, Dileep; Abidi, A. B.

    2014-01-01

    Oxidative stress plays a vital role in diabetic complications. To suppress the oxidative stress mediated damage in diabetic pathophysiology, a special focus has been given on composite extract (CE) and making small dose of naturally occurring antidiabetic plants leaf and fruits. The aim of the present study was to evaluate the beneficial role of CE against alloxan- (ALX-) induced diabetes of Wistar strain rats. A dose-dependent study for CE (25, 50, and 100?mg/kg body weight) was carried out to find the effective dose of the composite compound in ALX-induced diabetic rats. ALX exposure elevated the blood glucose, plasma advanced oxidation product (AOPP), sialic acid demonstrating disturbed antioxidant status.CE at a dose of 100?mg/kg body weight restored/minimised these alterations towards normal values. In conclusion, small dose of CE possesses the capability of ameliorating the oxidative stress in ALX-induced diabetes and thus could be a promising approach in lessening diabetic complications. PMID:24729889

  19. D-saccharic acid-1,4-lactone ameliorates alloxan-induced diabetes mellitus and oxidative stress in rats through inhibiting pancreatic beta-cells from apoptosis via mitochondrial dependent pathway

    SciTech Connect

    Bhattacharya, Semantee; Manna, Prasenjit; Sil, Parames C.

    2011-12-15

    Oxidative stress plays a vital role in diabetic complications. To suppress the oxidative stress mediated damage in diabetic pathophysiology, a special focus has been given on naturally occurring antioxidants present in normal diet. D-saccharic acid 1,4-lactone (DSL), a derivative of D-glucaric acid, is present in many dietary plants and is known for its detoxifying and antioxidant properties. The aim of the present study was to evaluate the beneficial role of DSL against alloxan (ALX) induced diabetes in the pancreas tissue of Swiss albino rats. A dose-dependent study for DSL (20-120 mg/kg body weight) was carried out to find the effective dose of the compound in ALX-induced diabetic rats. ALX exposure elevated the blood glucose, glycosylated Hb, decreased the plasma insulin and disturbed the intra-cellular antioxidant machineries whereas oral administration of DSL at a dose of 80 mg/kg body weight restored these alterations close to normal. Investigating the mechanism of the protective activity of DSL we observed that it prevented the pancreatic {beta}-cell apoptosis via mitochondria-dependent pathway. Results showed decreased mitochondrial membrane potential, enhanced cytochrome c release in the cytosol and reciprocal regulation of Bcl-2 family proteins in the diabetic rats. These events were also found to be associated with increased level of Apaf-1, caspase 9, and caspase 3 that ultimately led to pancreatic {beta}-cell apoptosis. DSL treatment, however, counteracted these changes. In conclusion, DSL possesses the capability of ameliorating the oxidative stress in ALX-induced diabetes and thus could be a promising approach in lessening diabetic complications. Highlights: Black-Right-Pointing-Pointer Oxidative stress is suggested as a key event in the pathogenesis of diabetes. Black-Right-Pointing-Pointer D-saccharic acid 1,4-lactone (DSL) reduces the alloxan-induced diabetes mellitus. Black-Right-Pointing-Pointer DSL normalizes cellular antioxidant machineries disturbed due to alloxan toxicity. Black-Right-Pointing-Pointer DSL inhibits pancreatic {beta}-cells apoptosis via mitochondria-dependent pathway. Black-Right-Pointing-Pointer DSL could be a promising approach for the treatment of diabetes mellitus.

  20. Taurine exerts hypoglycemic effect in alloxan-induced diabetic rats, improves insulin-mediated glucose transport signaling pathway in heart and ameliorates cardiac oxidative stress and apoptosis

    SciTech Connect

    Das, Joydeep; Vasan, Vandana; Sil, Parames C.

    2012-01-15

    Hyperlipidemia, inflammation and altered antioxidant profiles are the usual complications in diabetes mellitus. In the present study, we investigated the therapeutic potential of taurine in diabetes associated cardiac complications using a rat model. Rats were made diabetic by alloxan (ALX) (single i.p. dose of 120 mg/kg body weight) and left untreated or treated with taurine (1% w/v, orally, in water) for three weeks either from the day of ALX exposure or after the onset of diabetes. Animals were euthanized after three weeks. ALX-induced diabetes decreased body weight, increased glucose level, decreased insulin content, enhanced the levels of cardiac damage markers and altered lipid profile in the plasma. Moreover, it increased oxidative stress (decreased antioxidant enzyme activities and GSH/GSSG ratio, increased xanthine oxidase enzyme activity, lipid peroxidation, protein carbonylation and ROS generation) and enhanced the proinflammatory cytokines levels, activity of myeloperoxidase and nuclear translocation of NF?B in the cardiac tissue of the experimental animals. Taurine treatment could, however, result to a decrease in the elevated blood glucose and proinflammatory cytokine levels, diabetes-evoked oxidative stress, lipid profiles and NF?B translocation. In addition, taurine increased GLUT 4 translocation to the cardiac membrane by enhanced phosphorylation of IR and IRS1 at tyrosine and Akt at serine residue in the heart. Results also suggest that taurine could protect cardiac tissue from ALX induced apoptosis via the regulation of Bcl2 family and caspase 9/3 proteins. Taken together, taurine supplementation in regular diet could play a beneficial role in regulating diabetes and its associated complications in the heart. Highlights: ? Taurine controls blood glucose via protection of pancreatic ? cells in diabetic rat. ? Taurine controls blood glucose via increasing the insulin level in diabetic rat. ? Taurine improves cardiac AKT/GLUT4 signaling pathways in diabetic conditions. ? Taurine exerts antioxidant, antihyperlipidemic and antiinflammatory activities. ? It protects cardiac apoptosis by regulating Bcl2 family and caspase 9/3 proteins.

  1. Polysaccharides from Laminaria japonica show hypoglycemic and hypolipidemic activities in mice with experimentally induced diabetes.

    PubMed

    Jia, Xibei; Yang, Juan; Wang, Zhi; Liu, Ruichan; Xie, Rujuan

    2014-12-01

    Diabetes mellitus (DM) is a chronic metabolic disorder of the endocrine system. The rapid increase in the incidence of DM is a serious public health concern worldwide. The treatment of DM and its complications mainly involves the use of chemically or biochemically synthesized drugs, but these drugs also have adverse side effects. Therefore, there is an urgent need to search for drugs from natural sources that would cause fewer side effects. This study aimed to determine whether polysaccharides from Laminaria japonica (LJP) exert hypoglycemic and hypolipidemic effects in mice with alloxan-induced diabetes. To this end, diabetes was induced by alloxan injection (200?mg/kg body weight [bw], intraperitoneal [ip]). After induction of diabetes, diabetic mice were randomly divided into five groups: diabetic control (DC) group, glibenclamide-treated (DG) group, low-dose LJP-treated (DLL) group, moderate-dose LJP-treated (DML) group, and high-dose LJP-treated (DHL) group, with normal mice used as the control group (NC group). After treatment for 28 days, body weight, fasting blood glucose (FBG), serum insulin, total cholesterol (TC), triglyceride (TG), high-density lipoprotein-cholesterol (HDL-C), and low-density lipoprotein-cholesterol (LDL-C) levels were measured. The results revealed that LJP administration prevented body-weight loss, decreased FBG levels, and increased serum insulin levels in diabetic mice. Furthermore, it decreased TC, TG, and LDL-C levels, and increased HDL-C levels in these mice. Thus, the results indicate that LJP possesses hypoglycemic and hypolipidemic activities and polysaccharides from LJP may hold promise for the development of a drug of natural origin for the treatment of DM. PMID:24928865

  2. Comparison of cerebral microcirculation of alloxan diabetes and healthy mice using laser speckle contrast imaging

    NASA Astrophysics Data System (ADS)

    Timoshina, Polina A.; Shi, Rui; Zhang, Yang; Zhu, Dan; Semyachkina-Glushkovskaya, Oxana V.; Tuchin, Valery V.; Luo, Qingming

    2015-03-01

    The study of blood microcirculation is one of the most important problems of the medicine. This paper presents results of experimental study of cerebral blood flow microcirculation in mice with alloxan-induced diabetes using Temporal Laser Speckle Imaging (TLSI). Additionally, a direct effect of glucose water solution (concentration 20% and 45%) on blood flow microcirculation was studied. In the research, 20 white laboratory mice weighing 20-30 g were used. The TLSI method allows one to investigate time dependent scattering from the objects with complex dynamics, since it possesses greater temporal resolution. Results show that in brain of animal diabetic group diameter of sagittal vein is increased and the speed of blood flow reduced relative to the control group. Topical application of 20%- or 45%-glucose solutions also causes increase of diameter of blood vessels and slows down blood circulation. The results obtained show that diabetes development causes changes in the cerebral microcirculatory system and TLSI techniques can be effectively used to quantify these alterations.

  3. Beta Cell Mass Restoration in Alloxan-Diabetic Mice Treated with EGF and Gastrin

    PubMed Central

    Song, Imane; Patel, Oelfah; Himpe, Eddy; Muller, Christo J. F.; Bouwens, Luc

    2015-01-01

    One week of treatment with EGF and gastrin (EGF/G) was shown to restore normoglycemia and to induce islet regeneration in mice treated with the diabetogenic agent alloxan. The mechanisms underlying this regeneration are not fully understood. We performed genetic lineage tracing experiments to evaluate the contribution of beta cell neogenesis in this model. One day after alloxan administration, mice received EGF/G treatment for one week. The treatment could not prevent the initial alloxan-induced beta cell mass destruction, however it did reverse glycemia to control levels within one day, suggesting improved peripheral glucose uptake. In vitro experiments with C2C12 cell line showed that EGF could stimulate glucose uptake with an efficacy comparable to that of insulin. Subsequently, EGF/G treatment stimulated a 3-fold increase in beta cell mass, which was partially driven by neogenesis and beta cell proliferation as assessed by beta cell lineage tracing and BrdU-labeling experiments, respectively. Acinar cell lineage tracing failed to show an important contribution of acinar cells to the newly formed beta cells. No appearance of transitional cells co-expressing insulin and glucagon, a hallmark for alpha-to-beta cell conversion, was found, suggesting that alpha cells did not significantly contribute to the regeneration. An important fraction of the beta cells significantly lost insulin positivity after alloxan administration, which was restored to normal after one week of EGF/G treatment. Alloxan-only mice showed more pronounced beta cell neogenesis and proliferation, even though beta cell mass remained significantly depleted, suggesting ongoing beta cell death in that group. After one week, macrophage infiltration was significantly reduced in EGF/G-treated group compared to the alloxan-only group. Our results suggest that EGF/G-induced beta cell regeneration in alloxan-diabetic mice is driven by beta cell neogenesis, proliferation and recovery of insulin. The glucose-lowering effect of the treatment might play an important role in the regeneration process. PMID:26452142

  4. Ghrelin reverses experimental diabetic neuropathy in mice

    SciTech Connect

    Kyoraku, Itaru; Shiomi, Kazutaka; Kangawa, Kenji; Nakazato, Masamitsu

    2009-11-20

    Ghrelin, an acylated peptide produced in the stomach, increases food intake and growth hormone secretion, suppresses inflammation and oxidative stress, and promotes cell survival and proliferation. We investigated the pharmacological potential of ghrelin in the treatment of polyneuropathy in uncontrolled streptozotocin (STZ)-induced diabetes in mice. Ghrelin or desacyl-ghrelin was administered daily for 4 weeks after STZ-induced diabetic polyneuropathy had developed. Ghrelin administration did not alter food intake, body weight gain, blood glucose levels, or plasma insulin levels when compared with mice given saline or desacyl-ghrelin administration. Ghrelin administration ameliorated reductions in motor and sensory nerve conduction velocities in diabetic mice and normalized their temperature sensation and plasma concentrations of 8-isoprostaglandin {alpha}, an oxidative stress marker. Desacyl-ghrelin failed to have any effect. Ghrelin administration in a mouse model of diabetes ameliorated polyneuropathy. Thus, ghrelin's effects represent a novel therapeutic paradigm for the treatment of this otherwise intractable disorder.

  5. Hypoglycemic Effect of Combination of Azadirachta indica A. Juss. and Gynura procumbens (Lour.) Merr. Ethanolic Extracts Standardized by Rutin and Quercetin in Alloxan-induced Hyperglycemic Rats

    PubMed Central

    Sunarwidhi, Anggit Listyacahyani; Sudarsono, Sudarsono; Nugroho, Agung Endro

    2014-01-01

    Purpose: Exploration of plant combinations could be an alternative approach for diabetes treatment. The aim of this study is to evaluate the hypoglycemic effect of combination of A. indica and G. procumbens ethanolic extracts in alloxan-induced diabetic rats. Methods: Powder of A. indica and G. procumbens leaves were macerated with ethanol 70%. Determination of rutin in A. indica and quercetin in G. procumbens were performed by TLC-densitometry. Hyperglycemia in rats was induced by an intraperitoneal injection of alloxan monohydrate at a single dose of 150 mg/kgBW. The rats were treated with 3 dosage variation of combinations for 15 days. Hypoglycemic effect was evaluated by estimating the blood glucose levels and the rats pancreas histological study. Results: A. indica contained 2.90±0.15% of rutin and G. procumbens contained 18.86±0.86% of quercetin. Combination at the ratio of 50mg/kgBW A. indica:112.5mg/kgBW G. procumbens showed the highest hypoglycemic effect: 68.74±4.83% (preprandial) and 73.91±3.18% (postprandial). Histological studies indicated that this combination improved the morphology of the islets of Langerhans and ? cells. It also increased insulin expression and decreased the elevated-glucose concentrations. Conclusion: This study showed that combination of both extracts has better hypoglycemic effect than the single treatment of A. indica or G. procumbens. Combination of both extracts was potential to develop as a blood glucose-lowering agent for diabetic patients. PMID:25671197

  6. Exercise training modifies gut microbiota in normal and diabetic mice.

    PubMed

    Lambert, Jennifer E; Myslicki, Jason P; Bomhof, Marc R; Belke, Darrell D; Shearer, Jane; Reimer, Raylene A

    2015-07-01

    Cecal microbiota from type 2 diabetic (db/db) and control (db/(+)) mice was obtained following 6 weeks of sedentary or exercise activity. qPCR analysis revealed a main effect of exercise, with greater abundance of select Firmicutes species and lower Bacteroides/Prevotella spp. in both normal and diabetic exercised mice compared with sedentary counterparts. Conversely, Bifidobacterium spp. was greater in exercised normal but not diabetic mice (exercise × diabetes interaction). How exercise influences gut microbiota requires further investigation. PMID:25962839

  7. CFUs reduction and adaptation in mice with experimental diabetes.

    PubMed

    Poljak-Blazi, M; Slijepcevi?, M; Borani?, M

    1980-02-01

    Experimental diabetes was induced in mice by an intravenous injection of alloxan, 75 mg/kg. Bone marrow cells (8 X 10(4)) from nondiabetic or diabetic mice, 2, 14 or 30 days after induction of diabetes, were injected into lethally irradiated (850 R) nondiabetic or diabetic recipients, and the development of splenic hemopoietic colonies was determined 8 days later. In nondiabetic recipients, bone marrow cells from both types of the donors formed equal numbers of spleen colonies. In diabetic recipients, bone marrow cells from nondiabetic mice produced fewer colonies, whereas bone marrow cels from donors that had diabetes for 14 or 30 days formed as many colonies as in nondiabetic mice. Daily injections of insulin into diabetic recipients improved the colony producing capacity of nondiabetic bone marrow cells. We conclude that bone marrow stem cells (CFUs) acquire resistance to adverse metabolic conditions of hypoinsulinemia and hyperglycemia. Adapted bone marrow cells function well in either the diabetic or nondiabetic environment. PMID:7009182

  8. Protective effects of Quercus salicina on alloxan-induced oxidative stress in HIT-T15 pancreatic ? cells

    PubMed Central

    SONG, JIA-LE; ZHAO, XIN; WANG, QIANG

    2013-01-01

    The present study was designed to investigate the protective effect of hot water extracts from Quercus salicina leaves (QSWE) on alloxan-induced oxidative stress in HIT-T15 Syrian hamster pancreatic insulinoma cells. The HIT-T15 cells were treated with alloxan (1 mM) for 1 h and then co-incubated with the QSWE for 24 h. Alloxan significantly decreased the viability of the HIT-T15 cells (P<0.05). QSWE did not exhibit significantly cytotoxic effects and increased the viability of the HIT-T15 cells in a concentration-dependent manner. To further investigate the protective effects of QSWE on alloxan-induced oxidative stress in HIT-T15 cells, the cellular levels of reactive oxygen species (ROS), lipid peroxidation and endogenous antioxidant enzymes, including catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-px), were analyzed. QSWE decreased the intracellular levels of ROS and lipid peroxidation and increased the activity of antioxidant enzymes. These results suggest that QSWE exerted cytoprotective activity against alloxan-induced oxidative stress in HIT-T15 cells through the inhibition of lipid peroxidation, reduction of ROS levels and stimulation of antioxidant enzyme activity. In addition, QSWE also increased the insulin secretion activity of the alloxan-treated HIT-T15 cells. PMID:23408741

  9. Chronic rapamycin treatment causes diabetes in male mice

    PubMed Central

    Schindler, Christine E.; Partap, Uttara; Patchen, Bonnie K.

    2014-01-01

    Current evidence indicates that the mammalian target of rapamycin inhibitor rapamycin both increases longevity and, seemingly contradictorily, impairs glucose homeostasis. Most studies exploring the dimensions of this paradox have been based on rapamycin treatment in mice for up to 20 wk. We sought to better understand the metabolic effects of oral rapamycin over a substantially longer period of time in HET3 mice. We observed that treatment with rapamycin for 52 wk induced diabetes in male mice, characterized by hyperglycemia, significant urine glucose levels, and severe glucose and pyruvate intolerance. Glucose intolerance occurred in male mice by 4 wk on rapamycin and could be only partially reversed with cessation of rapamycin treatment. Female mice developed moderate glucose intolerance over 1 yr of rapamycin treatment, but not diabetes. The role of sex hormones in the differential development of diabetic symptoms in male and female mice was further explored. HET3 mice treated with rapamycin for 52 wk were gonadectomized and monitored over 10 wk. Castrated male mice remained glucose intolerant, while ovariectomized females developed significant glucose intolerance over the same time period. Subsequent replacement of 17?-estradiol (E2) in ovariectomized females promoted a recovery of glucose tolerance over a 4-wk period, suggesting the protective role of E2 against rapamycin-induced diabetes. These results indicate that 1) oral rapamycin treatment causes diabetes in male mice, 2) the diabetes is partially reversible with cessation of treatment, and 3) E2 plays a protective role against the development of rapamycin-induced diabetes. PMID:24965794

  10. Therapeutic Effects of Bupleurum Polysaccharides in Streptozotocin Induced Diabetic Mice

    PubMed Central

    Li, Hong; Liu, Zhenzhen; Xu, Yanyan; Zhou, Chunjiao; Lu, Xiaoxiao; Su, Xiaoyu; Zhang, Yunyi; Chen, Daofeng

    2015-01-01

    Diabetes mellitus is related to low-grade chronic inflammation and oxidative stress. Bupleurum Polysaccharides (BPs), isolated from Bupleurum smithii var. parvifolium has anti-inflammatory and anti-oxidative properties. However, little is known about its therapeutic effects on diabetes. In this experiment, the effects of BPs on alleviation of diabetes and the underlying mechanisms were investigated. Diabetic mice model was established via successive intraperitoneal injections of streptozotocin (100 mg/kg body weight) for two days. Mice with blood glucose levels higher than 16.8mmol/L were selected for experiments. The diabetic mice were orally administered with BPs (30 and 60 mg/kg) once a day for 35 days. BPs not only significantly decreased levels of blood glucose, but also increased those of serum insulin and liver glycogen in diabetic mice compared to model mice. Additionally, BPs adminstration improved the insulin expression and suppressed the apoptosis in pancreas of the diabetic mice. Histopathological observations further demonstrated that BPs protected the pancreas and liver from oxidative and inflammatory damages. These results suggest that BPs protect pancreatic ? cells and liver hepatocytes and ameliorate diabetes, which is associated with its anti-oxidative and anti-inflammatory properties. PMID:26176625

  11. Decreased thyroidal response to thyrotropin in diabetic mice

    SciTech Connect

    Bagchi, N.; Brown, T.R.; Shivers, B.; Lucas, S.; Mack, R.E.

    1981-11-01

    The effect of diabetes mellitus on the synthesis and secretion of thyroid hormone ws investigated in mice with streptozotocin-induced diabetes. Thyroid glands were labeled in vivo with 131I for 2 h. In control animals, TSH stimulated the synthesis of PB127I and 131I-labeled iodothyronines and simultaneously decreased the proportion of 131I-. These effects of TSH were not observed in diabetic animals but were demonstrable in diabetic animals treated with insulin. For studies of hormone secretion, labeled thyroid glands were cultured in vitro in medium containing 1 mM mononitrotyrosine. The rate of the hydrolysis of labeled thyroglobulin was measured as the proportion of 131I-labeled iodotyrosines and 131I-labeled iodothyronines recovered at the end of culture and was used as an index of thyroid secretion. TSH in vivo stimulated the rate of thyroglobulin hydrolysis for 6 h, with a peak occurring after 2 h. The diabetic mice had a diminished response to TSH, which improved on treatment with insulin. The addition of TSH and insulin to the culture medium significantly increased the rate of thyroglobulin hydrolysis in glands of diabetic mice over that resulting from the addition of dibutyryl cAMP alone. The generation of thyroidal cAMP in response to TSH was higher in diabetic mice than in controls. The rise in plasma T4 and T3 2 h after the administration of TSH was less in diabetic mice than in control mice or diabetic mice treated with insulin. Our studies, therefore, indicate that the thyroidal response to TSH is decreased in diabetes mellitus. The defect appears to be at a step beyond the generation of cAMP.

  12. Mycophenolate Mofetil Ameliorates Diabetic Nephropathy in db/db Mice

    PubMed Central

    Seo, Jung-Woo; Kim, Yang Gyun; Lee, Sang Ho; Lee, Arah; Kim, Dong-Jin; Jeong, Kyung-Hwan; Lee, Kyung Hye; Hwang, Seung Joon; Woo, Jong Shin; Lim, Sung Jig; Kim, Weon; Moon, Ju-Young

    2015-01-01

    Chronic low-grade inflammation is an important factor in the pathogenesis of diabetic complication. Mycophenolate mofetil (MMF) has an anti-inflammatory effect, inhibiting lymphocyte proliferation. Previous studies showed attenuation of diabetic nephropathy with MMF, but the underlying mechanisms were unclear. This study aimed to identify the effect of MMF on diabetic nephropathy and investigate its action mechanisms in type 2 diabetic mice model. Eight-week-old db/db and control mice (db/m mice) received vehicle or MMF at a dose of 30?mg/kg/day for 12 weeks. MMF-treated diabetic mice showed decreased albuminuria, attenuated mesangial expansion, and profibrotic mRNA expressions despite the high glucose level. The number of infiltrated CD4+ and CD8+ T cells in the kidney was significantly decreased in MMF-treated db/db mice and it resulted in attenuating elevated intrarenal TNF-? and IL-17. The renal chemokines expression and macrophages infiltration were also attenuated by MMF treatment. The decreased expression of glomerular nephrin and WT1 was recovered with MMF treatment. MMF prevented the progression of diabetic nephropathy in db/db mice independent of glycemic control. These results suggest that the effects of MMF in diabetic nephropathy are mediated by CD4+ T cell regulation and related cytokines. PMID:26345532

  13. Hypoglycemic activity and acute oral toxicity of chromium methionine complexes in mice.

    PubMed

    Tang, Hai-yan; Xiao, Qing-gui; Xu, Hong-bin; Zhang, Yi

    2015-01-01

    The hypoglycemic activity of chromium methionine (CrMet) in alloxan-induced diabetic (AID) mice was investigated and compared with those of chromium trichloride hexahydrate (CrCl3·6H2O) and chromium nicotinate (CrNic) through a 15-day feeding experiment. The acute oral toxicity of CrMet was also investigated in ICR (Institute for Cancer Research) mice by a single oral gavage. The anti-diabetic activity of CrMet was explored in detail from the aspects of body weight (BW), blood glucose, triglyceride, total cholesterol, liver glycogen levels, aspartate transaminase (AST) and alanine transaminase (ALT) levels. The obtained results showed that CrMet had beneficial effects on glucose and lipid metabolism, and might possess hepatoprotective efficacy for diabetes. Daily treatment with 500 and 1000?g Cr/kg BW of CrMet in AID mice for 15 days indicated that this low-molecular-weight organic chromium complex had better bioavailability and more beneficial effects on diabetics than CrCl3·6H2O. CrMet also had advantage over CrNic in the control of AST and ALT activities. Acute toxicity studies revealed that CrMet had low toxicity potential and relatively high safety margins in mice with the LD50 value higher than 10.0g/kg BW. These findings suggest that CrMet might be of potential value in the therapy and protection of diabetes. PMID:25081494

  14. Reduced Incidence and Delayed Onset of Diabetes in Perforin-deficient Nonobese Diabetic Mice

    PubMed Central

    Kägi, David; Odermatt, Bernhard; Seiler, Peter; Zinkernagel, Rolf M.; Mak, Tak W.; Hengartner, Hans

    1997-01-01

    To investigate the role of T cell–mediated, perforin-dependent cytotoxicity in autoimmune diabetes, perforin-deficient mice were backcrossed with the nonobese diabetes mouse strain. It was found that the incidence of spontaneous diabetes over a 1 yr period was reduced from 77% in perforin +/+ control to 16% in perforin-deficient mice. Also, the disease onset was markedly delayed (median onset of 39.5 versus 19 wk) in the latter. Insulitis with infiltration of CD4+ and CD8+ T cells occurred similarly in both groups of animals. Lower incidence and delayed disease onset were also evident in perforin-deficient mice when diabetes was induced by cyclophosphamide injection. Thus, perforin-dependent cytotoxicity is a crucial effector mechanism for ? cell elimination by cytotoxic T cells in autoimmune diabetes. However, in the absence of perforin chronic inflammation of the islets can lead to diabetogenic ? cell loss by less efficient secondary effector mechanisms. PMID:9314549

  15. Histidine Decarboxylase Deficiency Prevents Autoimmune Diabetes in NOD Mice

    PubMed Central

    Alkan, Manal; Machavoine, François; Rignault, Rachel; Dam, Julie; Dy, Michel; Thieblemont, Nathalie

    2015-01-01

    Recent evidence has highlighted the role of histamine in inflammation. Since this monoamine has also been strongly implicated in the pathogenesis of type-1 diabetes, we assessed its effect in the nonobese diabetic (NOD) mouse model. To this end, we used mice (inactivated) knocked out for the gene encoding histidine decarboxylase, the unique histamine-forming enzyme, backcrossed on a NOD genetic background. We found that the lack of endogenous histamine in NOD HDC?/? mice decreased the incidence of diabetes in relation to their wild-type counterpart. Whereas the proportion of regulatory T and myeloid-derived suppressive cells was similar in both strains, histamine deficiency was associated with increased levels of immature macrophages, as compared with wild-type NOD mice. Concerning the cytokine pattern, we found a decrease in circulating IL-12 and IFN-? in HDC?/? mice, while IL-6 or leptin remained unchanged, suggesting that histamine primarily modulates the inflammatory environment. Paradoxically, exogenous histamine given to NOD HDC?/? mice provided also protection against T1D. Our study supports the notion that histamine is involved in the pathogenesis of diabetes, thus providing additional evidence for its role in the regulation of the immune response. PMID:26090474

  16. Mitochondrial Dysfunction and Apoptosis in Cumulus Cells of Type I Diabetic Mice

    E-print Network

    Mitochondrial Dysfunction and Apoptosis in Cumulus Cells of Type I Diabetic Mice Qiang Wang1 demonstrated in diabetic mice; however, the potential pathways by which maternal diabetes exerts its effects of maternal diabetes on the mitochondrial status in cumulus cells. We found an increased frequency

  17. Expression profiling pre-diabetic mice to uncover drugs with clinical application to type 1 diabetes

    PubMed Central

    Pang, Dimeng; Irvine, Katharine M; Mehdi, Ahmed M; Thomas, Helen E; Harris, Mark; Hamilton-Williams, Emma E; Thomas, Ranjeny

    2015-01-01

    In the NOD mouse model of type 1 diabetes (T1D), genetically identical mice in the same environment develop diabetes at different rates. Similar heterogeneity in the rate of progression to T1D exists in humans, but the underlying mechanisms are unclear. Here, we aimed to discover peripheral blood (PB) genes in NOD mice predicting insulitis severity and rate of progression to diabetes. We then wished to use these genes to mine existing databases to identify drugs effective in diabetes. In a longitudinal study, we analyzed gene expression in PB samples from NOD.CD45.2 mice at 10 weeks of age, then scored pancreatic insulitis at 14 weeks or determined age of diabetes onset. In a multilinear regression model, Tnf and Tgfb mRNA expression in PB predicted insulitis score (R2=0.56, P=0.01). Expression of these genes did not predict age of diabetes onset. However, by expression-profiling PB genes in 10-week-old NOD.CD45.2 mice, we found a signature of upregulated genes that predicted delayed or no diabetes. Major associated pathways included chromatin organization, cellular protein location and regulation of nitrogen compounds and RNA. In a clinical cohort, three of these genes were differentially expressed between first-degree relatives, T1D patients and controls. Bioinformatic analysis of differentially expressed genes in NOD.CD45.2 PB identified drugs that are predicted to delay or prevent diabetes. Of these drugs, 11 overlapped with drugs predicted to induce a human ‘non-progressor' expression profile. These data demonstrate that disease heterogeneity in diabetes-prone mice can be exploited to mine novel clinical T1D biomarkers and drug targets. PMID:26366287

  18. Expression profiling pre-diabetic mice to uncover drugs with clinical application to type 1 diabetes.

    PubMed

    Pang, Dimeng; Irvine, Katharine M; Mehdi, Ahmed M; Thomas, Helen E; Harris, Mark; Hamilton-Williams, Emma E; Thomas, Ranjeny

    2015-08-01

    In the NOD mouse model of type 1 diabetes (T1D), genetically identical mice in the same environment develop diabetes at different rates. Similar heterogeneity in the rate of progression to T1D exists in humans, but the underlying mechanisms are unclear. Here, we aimed to discover peripheral blood (PB) genes in NOD mice predicting insulitis severity and rate of progression to diabetes. We then wished to use these genes to mine existing databases to identify drugs effective in diabetes. In a longitudinal study, we analyzed gene expression in PB samples from NOD.CD45.2 mice at 10 weeks of age, then scored pancreatic insulitis at 14 weeks or determined age of diabetes onset. In a multilinear regression model, Tnf and Tgfb mRNA expression in PB predicted insulitis score (R (2)=0.56, P=0.01). Expression of these genes did not predict age of diabetes onset. However, by expression-profiling PB genes in 10-week-old NOD.CD45.2 mice, we found a signature of upregulated genes that predicted delayed or no diabetes. Major associated pathways included chromatin organization, cellular protein location and regulation of nitrogen compounds and RNA. In a clinical cohort, three of these genes were differentially expressed between first-degree relatives, T1D patients and controls. Bioinformatic analysis of differentially expressed genes in NOD.CD45.2 PB identified drugs that are predicted to delay or prevent diabetes. Of these drugs, 11 overlapped with drugs predicted to induce a human 'non-progressor' expression profile. These data demonstrate that disease heterogeneity in diabetes-prone mice can be exploited to mine novel clinical T1D biomarkers and drug targets. PMID:26366287

  19. Ergosterol Alleviates Kidney Injury in Streptozotocin-Induced Diabetic Mice

    PubMed Central

    Ang, Li; Yuguang, Liu; Liying, Wang; Shuying, Zhang; Liting, Xu; Shumin, Wang

    2015-01-01

    Ergosterol (ERG) has been widely used in the development of novel drugs due to its unique physiological function. However, little is known about the protective effects of ERG on diabetes. Hence, the current study was designed to evaluate the positive role of ergosterol on streptozotocin- (STZ-) induced diabetes in mice. Oral glucose tolerance test (OGTT) was carried out to assess blood glucose level. Biochemical parameters such as uric acid, creatinine, serum insulin, triglycerides (TG), and total cholesterol (TC) were also measured. Pathological condition of kidney was examined by hematoxylin-eosin (H&E) staining. The expressions of PI3K, p-PI3K, Akt, p-Akt, NF-?Bp65, p-NF-?Bp65, I?B?, and p-I?B? were analyzed by western blot. ERG significantly reduced the concentrations of blood glucose, uric acid, creatinine, TG, and TC. Serum insulin was elevated with ERG treatment. In addition, renal pathologic changes of diabetes mice were also alleviated by ERG. Obtained data revealed that ERG restored the levels of PI3K/Akt/NF-?B signaling-related proteins in comparison with diabetes mice. Above all, it could be assumed that ERG might play a positive role in regulating STZ-induced diabetes through suppressing PI3K/Akt/NF-?B pathway. PMID:26664454

  20. Cutting Edge: Nonobese Diabetic Mice Deficient in Chromogranin A Are Protected from Autoimmune Diabetes.

    PubMed

    Baker, Rocky L; Bradley, Brenda; Wiles, Timothy A; Lindsay, Robin S; Barbour, Gene; Delong, Thomas; Friedman, Rachel S; Haskins, Kathryn

    2016-01-01

    T cells reactive to ? cell Ags are critical players in the development of autoimmune type 1 diabetes. Using a panel of diabetogenic CD4 T cell clones derived from the NOD mouse, we recently identified the ? cell secretory granule protein, chromogranin A (ChgA), as a new autoantigen in type 1 diabetes. CD4 T cells reactive to ChgA are pathogenic and rapidly transfer diabetes into young NOD recipients. We report in this article that NOD.ChgA(-/-) mice do not develop diabetes and show little evidence of autoimmunity in the pancreatic islets. Using tetramer analysis, we demonstrate that ChgA-reactive T cells are present in these mice but remain naive. In contrast, in NOD.ChgA(+/+) mice, a majority of the ChgA-reactive T cells are Ag experienced. Our results suggest that the presence of ChgA and subsequent activation of ChgA-reactive T cells are essential for the initiation and development of autoimmune diabetes in NOD mice. PMID:26608914

  1. Modeling Type 1 Diabetes in NOD Mice

    E-print Network

    Mahaffy, Joseph M.

    -protein to prevent autoimmunity · T cells migrate to Lymph nodes - Interact with antigen presenting cells (APCs-MHC Apoptotic cell PANCREAS LYMPH NODE Dendritic cell peptide p Cell injury Diabetes Oct 2006 ­ p. 11/3 #12 subunit-related protein) produces a dominant antigen · Experiments designed t

  2. Anti-diabetic activity of a mineraloid isolate, in vitro and in genetically diabetic mice.

    PubMed

    Deneau, Joel; Ahmed, Taufeeq; Blotsky, Roger; Bojanowski, Krzysztof

    2011-01-01

    Type II diabetes is a metabolic disease mediated through multiple molecular pathways. Here, we report anti-diabetic effect of a standardized isolate from a fossil material - a mineraloid leonardite - in in vitro tests and in genetically diabetic mice. The mineraloid isolate stimulated mitochondrial metabolism in human fibroblasts and this stimulation correlated with enhanced expression of genes coding for mitochondrial proteins such as ATP synthases and ribosomal protein precursors, as measured by DNA microarrays. In the diabetic animal model, consumption of the Totala isolate resulted in decreased weight gain, blood glucose, and glycated hemoglobin. To our best knowledge, this is the first description ever of a fossil material having anti-diabetic activity in pre-clinical models. PMID:22002216

  3. Use of NOD Mice to Understand Human Type 1 Diabetes

    PubMed Central

    Thayer, Terri C.; Wilson, Brian S.; Mathews, Clayton E.

    2010-01-01

    Synopsis In 1922, Leonard Thompson received the first injections of insulin prepared from the pancreas of canine test subjects. From pancreatectomized dogs to the more recent development of animal models that spontaneously develop autoimmune syndromes, animal models have played a meaningful role in furthering diabetes research. Of these animals the non-obese diabetic (NOD) mouse is the most widely used for research in Type 1 Diabetes (T1D) as the NOD shares a number of genetic and immunologic traits with the human form of the disease. In this chapter, we review both similarities and differences in NOD and human T1D and discuss the potential role of NOD mice in future pre-clinical studies aiming to provide a better understanding of the genetic and immune defects that lead to T1D. PMID:20723819

  4. Diabetes-resistant NOR mice are more severely affected by streptozotocin compared to the diabetes-prone NOD mice: correlations with liver and kidney GLUT2 expressions.

    PubMed

    Kahraman, S; Aydin, C; Elpek, G O; Dirice, E; Sanlioglu, A D

    2015-01-01

    Nonobese diabetic (NOD) mice are susceptible strains for Type 1 diabetes development, and Nonobese Diabetes-Resistant (NOR) mice are defined as suitable controls for NOD mice in non-MHC-related research. Diabetes is often accelerated in NOD mice via Streptozotocin (STZ). STZ is taken inside cells via GLUT2 transmembrane carrier proteins, the major glucose transporter isoforms in pancreatic beta cells, liver, kidneys, and the small intestine. We observed severe adverse effects in NOR mice treated with STZ compared to NOD mice that were made diabetic with a similar dose. We suggested that the underlying mechanism could be differential GLUT2 expressions in pancreatic beta cells, yet immunofluorescent and immunohistochemical studies revealed similar GLUT2 expression levels. We also detected GLUT2 expression profiles in NOD and NOR hepatic and renal tissues by western blot analysis and observed considerably higher GLUT2 expression levels in liver and kidney tissues of NOR mice. Although beta cell GLUT2 expression levels are frequently evaluated as a marker predicting STZ sensitivity in animal models, we report here very different diabetic responses to STZ in two different animal strains, in spite of similar initial GLUT2 expressions in beta cells. Furthermore, use of NOR mice in STZ-mediated experimental diabetes settings should be considered accordingly. PMID:25699277

  5. Epigallocatechin gallate delays the onset of type 1 diabetes in spontaneous non-obese diabetic mice.

    PubMed

    Fu, Zhuo; Zhen, Wei; Yuskavage, Julia; Liu, Dongmin

    2011-04-01

    Type 1 diabetes (T1D) results from the autoimmune-mediated destruction of pancreatic ?-cells, leading to deficiency of insulin production. Successful islet transplantation can normalise hyperglycaemia in T1D patients; however, the limited availability of the islets, loss of islet cell mass through apoptosis after islet isolation and potential autoimmune destruction of the transplanted islets prevent the widespread use of this procedure. Therefore, the search for novel and cost-effective agents that can prevent or treat T1D is extremely important to decrease the burden of morbidity from this disease. In the present study, we discovered that ( - )-epigallocatechin gallate (EGCG, 0·05 % in drinking-water), the primary polyphenolic component in green tea, effectively delayed the onset of T1D in non-obese diabetic (NOD) mice. At 32 weeks of age, eight (66·7 %) out of twelve mice in the control group developed diabetes, whereas only three (25 %) out of twelve mice in the EGCG-treated group became diabetic (P < 0·05). Consistently, mice supplemented with EGCG had significantly higher plasma insulin levels and survival rate but lower glycosylated Hb concentrations compared with the control animals. EGCG had no significant effects on food or water intake and body weight in mice, suggesting that the glucose-lowering effect was not due to an alteration in these parameters. While EGCG did not modulate insulitis, it elevated the circulating anti-inflammatory cytokine IL-10 level in NOD mice. These findings demonstrate that EGCG may be a novel, plant-derived compound capable of reducing the risk of T1D. PMID:21144096

  6. Obesity and diabetes in TNF-alpha receptor- deficient mice.

    PubMed Central

    Schreyer, S A; Chua, S C; LeBoeuf, R C

    1998-01-01

    TNF-alpha may play a role in mediating insulin resistance associated with obesity. This concept is based on studies of obese rodents and humans, and cell culture models. TNF elicits cellular responses via two receptors called p55 and p75. Our purpose was to test the involvement of TNF in glucose homeostasis using mice lacking one or both TNF receptors. C57BL/6 mice lacking p55 (p55(-)/-), p75, (p75(-)/-), or both receptors (p55(-)/-p75(-)/-) were fed a high-fat diet to induce obesity. Marked fasting hyperinsulinemia was seen for p55(-)/-p75(-)/- males between 12 and 16 wk of feeding the high-fat diet. Insulin levels were four times greater than wild-type mice. In contrast, p55(-)/- and p75(-)/- mice exhibited insulin levels that were similar or reduced, respectively, as compared with wild-type mice. In addition, high-fat diet-fed p75(-)/- mice had the lowest body weights and leptin levels, and improved insulin sensitivity. Obese (db/db) mice, which are not responsive to leptin, were used to study the role of p55 in severe obesity. Male p55(-)/-db/db mice exhibited threefold higher insulin levels and twofold lower glucose levels at 20 wk of age than control db/db expressing p55. All db/db mice remained severely insulin resistant based on fasting plasma glucose and insulin levels, and glucose and insulin tolerance tests. Our data do not support the concept that TNF, acting via its receptors, is a major contributor to obesity-associated insulin resistance. In fact, data suggest that the two TNF receptors work in concert to protect against diabetes. PMID:9664082

  7. Piceatannol lowers the blood glucose level in diabetic mice.

    PubMed

    Uchida-Maruki, Hiroko; Inagaki, Hiroyuki; Ito, Ryouichi; Kurita, Ikuko; Sai, Masahiko; Ito, Tatsuhiko

    2015-01-01

    We previously found that passion fruit (Passiflora edulis) seeds contained a high amount of piceatannol (3,5,3',4'-trans-tetrahydroxystilbene), a natural analog of resveratrol (3,5,4'-trans-trihydroxystilbene). Resveratrol has been proposed as a potential anti-metabolic disorder compound, by its activation of sirtuin and AMP-activated protein kinase. Many reports show that resveratrol ameliorates diet-induced obesity and insulin resistance. However, it is not known whether piceatannol also affects diet-induced obesity. We explored the effect of piceatannol on high fat diet-fed mice. The results showed that piceatannol did not affect high fat diet-induced body weight gain or visceral fat gain in mice. However, piceatannol did reduce fasting blood glucose levels. Furthermore, to explore the potential of passion fruit seed extract containing piceatannol as a functional food, passion fruit seed extract was administered in a genetic diabetic mouse model (db/db mice). Single administration of passion fruit seed extract, as well as piceatannol reduced the blood glucose levels of these db/db mice. These results suggest that piceatannol and passion fruit seed extract may have potential application in the prevention of diabetes. PMID:25832644

  8. Anti-diabetic effects of lactic acid bacteria in normal and type 2 diabetic mice

    PubMed Central

    Honda, Kayoko; Moto, Mihoko; Uchida, Naoko; He, Fang; Hashizume, Naotaka

    2012-01-01

    The antidiabetic effects of lactic acid bacteria were investigated using mice. In Experiment 1, normal ICR mice were loaded with sucrose or starch with or without viable Lactobacillus rhamnosus GG cells. GG significantly inhibited postprandial blood glucose levels when administered with sucrose or starch. In Experiment 2, KK-Ay mice, a model of genetic type 2 diabetes, were given a basal diet containing viable GG cells or viable Lactobacillus delbrueckii subsp. bulgaricus cells for 6 weeks. Viable GG cells significantly inhibited fasting blood glucose, postprandial blood glucose in a glucose tolerance test and HbA1c. Such effects were not shown by viable L. bulgaricus cells. In Experiment 3, the KK-Ay mice were given a basal diet containing viable GG cells or heat-treated GG cells for 3 weeks. The viable GG cells significantly suppressed fasting blood glucose and impaired glucose tolerance, but the heat-treated GG showed no effects. These results demonstrated that GG decreased the postprandial blood glucose in ICR mice, and that the antidiabetic activity of lactic acid bacteria on the KK-Ay mice differed depending on the bacterial strain and whether the bacterium is viable when it arrives in the intestine. In the present study, we conclude that the antidiabetic activity may result from continuous inhibition of the postprandial blood glucose through suppression of glucose absorption from the intestine. These findings indicate that specific strains of lactic acid bacterium can be expected to be beneficial for the management of type 2 diabetes. PMID:22962525

  9. Vascularization of wide pore agarose-gelatin cryogel scaffolds implanted subcutaneously in diabetic and non-diabetic mice.

    PubMed

    Bloch, K; Vanichkin, A; Damshkaln, L G; Lozinsky, V I; Vardi, P

    2010-03-01

    Polymeric scaffolds have been reported to promote angiogenesis, facilitating oxygen delivery; however, little is known about the effect of diabetes on the neo-vascularization of implanted polymeric scaffolds at subcutaneous (SC) sites. In this study we compare the effect of diabetes on scaffold vascularization following SC implantation into diabetic and non-diabetic mice. Wide pore agarose cryogel scaffolds with grafted gelatin were prepared by a two-step freezing procedure and subsequent thawing. The scaffolds were implanted subcutaneously into streptozoticin-induced diabetic mice and control, non-diabetic mice. The vascularization process was estimated using histological sections, in which endothelial cells were identified by Von Willebrand factor (vWF) and CD31 antigen staining and the pericyte layer was confirmed by alpha-smooth muscle actin (alpha-SMA) visualization. Comparative analysis showed a similar thickness of fibrous capsules around the vascularized scaffolds in both diabetic and non-diabetic animals. Intensive staining for alpha-SMA indicated the formation of mature blood vessels in the surrounding fibrous capsule and tissue invading the scaffold area. No statistically significant differences in capillary density and area occupied by blood vessels were found between diabetic and non-diabetic mice. In conclusion, the present study shows no adverse effects of diabetes on new blood vessel formation in SC implanted agarose cryogel scaffolds with grafted gelatin. PMID:19703598

  10. HoxD3 accelerates wound healing in diabetic mice

    SciTech Connect

    Hansen, Scott L.; Myers, Connie A.; Charboneau, Aubri; Young, David M.; and Boudreau, Nancy

    2003-12-01

    Poorly healing diabetic wounds are characterized by diminished collagen production and impaired angiogenesis. HoxD3, a homeobox transcription factor that promotes angiogenesis and collagen synthesis, is up-regulated during normal wound repair whereas its expression is diminished in poorly healing wounds of the genetically diabetic (db/db) mouse. To determine whether restoring expression of HoxD3 would accelerate diabetic wound healing, we devised a novel method of gene transfer, which incorporates HoxD3 plasmid DNA into a methylcellulose film that is placed on wounds created on db/db mice. The HoxD3 transgene was expressed in endothelial cells, fibroblasts, and keratinocytes of the wounds for up to 10 days. More importantly, a single application of HoxD3 to db/db mice resulted in a statistically significant acceleration of wound closure compared to control-treated wounds. Furthermore, we also observed that the HoxD3-mediated improvement in diabetic wound repair was accompanied by increases in mRNA expression of the HoxD3 target genes, Col1A1 and beta 3-integrin leading to enhanced angiogenesis and collagen deposition in the wounds. Although HoxD3-treated wounds also show improved re-epithelialization as compared to control db/db wounds, this effect was not due to direct stimulation of keratinocyte migration by HoxD3. Finally, we show that despite the dramatic increase in collagen synthesis and deposition in HoxD3-treated wounds, these wounds showed normal remodeling and we found no evidence of abnormal wound healing. These results indicate that HoxD3 may provide a means to directly improve collagen deposition, angiogenesis and closure in poorly healing diabetic wounds.

  11. Impaired response of mature adipocytes of diabetic mice to hypoxia

    SciTech Connect

    Hong, Seok Jong Jin, Da P.; Buck, Donald W.; Galiano, Robert D.; Mustoe, Thomas A.

    2011-10-01

    Adipose tissue contains various cells such as infiltrated monocytes/macrophages, endothelial cells, preadipocytes, and adipocytes. Adipocytes have an endocrine function by secreting adipokines such as interleukin (IL)-6, tumor necrosis factor (TNF)-{alpha}, leptin, and adiponectin. Dysregulation of adipokines in adipose tissues leads to a chronic low-grade inflammation which could result in atherosclerosis, hypertension, and type 2 diabetes. A sustained inflammatory state, which is characterized by prolonged persistence of macrophages and neutrophils, is found in diabetic wounds. In addition, subcutaneous adipocytes are enormously increased in amount clinically in type 2 diabetes. However, the function of subcutaneous adipocytes, which play an important role in injured tissue subjected to hypoxia, has not been well characterized in vitro due to the difficulty of maintaining mature adipocytes in culture using conventional methods because of their buoyancy. In this study, we established a novel in vitro culture method of mature adipocytes by enclosing them in a hyaluronan (HA) based hydrogel to study their role in response to stress such as hypoxia. BrdU labeling and Ki67 immunostaining experiments showed that hydrogel enclosed mature adipocytes proliferate in vitro. Both mRNA and protein expression analyses for hypoxia regulated genes, such as vascular endothelial growth factor (VEGF) and heme oxygenase 1 (HO1), showed that mature adipocytes of wild type mice respond to hypoxia. In contrast, mature adipocytes of diabetic db/db and TallyHo mice did not efficiently respond to hypoxia. Our studies suggest that mature adipocytes are functionally active cells, and their abnormal function to hypoxia can be one of underlining mechanisms in type 2 diabetes.

  12. Evaluation of venlafaxine on glucose homeostasis and oxidative stress in diabetic mice.

    PubMed

    Khanam, R; Najfi, H; Akhtar, M; Vohora, D

    2012-12-01

    Depression occurs frequently with diabetes affecting the quality of life. All major classes of antidepressants have been shown to have a direct pharmacologic effect on metabolic function, which further worsens glycemic control. There were no reports on the effects of venlafaxine on glucose levels and oxidative stress in diabetic animals. The present study evaluated the effects of venlafaxine (8 and 16 mg/kg per d) on glucose homeostasis along with oxidative stress in brain in diabetic mice (streptozotocin (STZ), 40 mg/kg per d for 5 days). We observed that 21 days of administration of venlafaxine (8 and 16 mg/kg per d) in diabetic mice significantly enhanced swimming in normal and STZ-treated mice with a corresponding reduction in immobility. No significant difference in blood glucose levels was observed in diabetic and normal mice following venlafaxine treatment. Venlafaxine (16 mg/kg) reversed STZ-induced elevated thiobarbituric acid reactive substance (TBARS) levels and also restored the glutathione (GSH) levels in diabetic mice. Venlafaxine (8 and 16 mg/kg) per se does not produce any significant effect in normal animals. The results indicate a dose-dependent antidepressant action of venlafaxine in diabetes-induced depressive mice. Furthermore, the blood glucose levels were not significantly altered in normal and diabetic mice. In addition, venlafaxine exhibited a decrease in TBARS and elevation in GSH levels in mice brain. Venlafaxine drug treatment appears to be safer for depression associated with diabetes. PMID:22751285

  13. Hepatic insulin gene therapy prevents diabetic enteropathy in STZ-treated CD-1 mice

    PubMed Central

    You, Shuo; Anitha, Mallappa; deSouza, Sean MD; Jia, Dingwu; Lu, Xianghua; Kozlowski, Miroslaw; Olson, Darin E; Srinivasan, Shanthi; Thulé, Peter M

    2015-01-01

    Depending on the population examined, from 6 to 83% of people with diabetes mellitus exhibit symptoms of altered gut motility, manifesting as dysphagia, reflux, early satiety, nausea, abdominal pain, diarrhea, or constipation. Hyperglycemia-induced cell loss within the enteric nervous system has been demonstrated in both diabetic rodents and patients with diabetes. Glycemic control is recommended to prevent diabetic gastroenteropathy but is often difficult to achieve with current treatment modalities. We asked if hepatic insulin gene therapy (HIGT) could inhibit the development of diabetic gastroenteropathy in mice. Bowel length, bowel transit, colonic muscle relaxation, and the numbers of both stimulatory and inhibitory neurons in the colonic myenteric plexus were compared in groups of diabetic mice (DM), control nondiabetic mice (Con), and diabetic mice treated with HIGT (HIGT). Delivery of a metabolically responsive insulin transgene to the liver of STZ-diabetic mice with an adeno-associated virus, sero-type 8 (AAV8) produced near-normal blood sugars for over 1 month and prevented anatomic, functional, and neurohistologic changes observed in diabetic mice. We conclude that in addition to normalizing oxidative metabolism in diabetic rodents, HIGT is sufficient to prevent the development of diabetic gastroenteropathy. PMID:26366426

  14. Petalonia improves glucose homeostasis in streptozotocin-induced diabetic mice

    SciTech Connect

    Kang, Seong-Il; Jin, Young-Jun; Ko, Hee-Chul; Choi, Soo-Youn; Hwang, Joon-Ho; Whang, Ilson; Kim, Moo-Han; Shin, Hye-Sun; Jeong, Hyung-Bok; Kim, Se-Jae

    2008-08-22

    The anti-diabetic potential of Petalonia binghamiae extract (PBE) was evaluated in vivo. Dietary administration of PBE to streptozotocin (STZ)-induced diabetic mice significantly lowered blood glucose levels and improved glucose tolerance. The mode of action by which PBE attenuated diabetes was investigated in vitro using 3T3-L1 cells. PBE treatment stimulated 3T3-L1 adipocyte differentiation as evidenced by increased triglyceride accumulation. At the molecular level, peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}) and terminal marker protein aP2, as well as the mRNA of GLUT4 were up-regulated by PBE. In mature adipocytes, PBE significantly stimulated the uptake of glucose and the expression of insulin receptor substrate-1 (IRS-1). Furthermore, PBE increased PPAR{gamma} luciferase reporter gene activity in COS-1 cells. Taken together, these results suggest that the in vivo anti-diabetic effect of PBE is mediated by both insulin-like and insulin-sensitizing actions in adipocytes.

  15. Baicalein Protects against Type 2 Diabetes via Promoting Islet ?-Cell Function in Obese Diabetic Mice

    PubMed Central

    Fu, Yu; Jia, Zhenquan; Zhen, Wei; Zhou, Kequan; Gilbert, Elizabeth

    2014-01-01

    In both type 1 (T1D) and type 2 diabetes (T2D), the deterioration of glycemic control over time is primarily caused by an inadequate mass and progressive dysfunction of ?-cell, leading to the impaired insulin secretion. Here, we show that dietary supplementation of baicalein, a flavone isolated from the roots of Chinese herb Scutellaria baicalensis, improved glucose tolerance and enhanced glucose-stimulated insulin secretion (GSIS) in high-fat diet (HFD-) induced middle-aged obese mice. Baicalein had no effect on food intake, body weight gain, circulating lipid profile, and insulin sensitivity in obese mice. Using another mouse model of type 2 diabetes generated by high-fat diet (HFD) feeding and low doses of streptozotocin injection, we found that baicalein treatment significantly improved hyperglycemia, glucose tolerance, and blood insulin levels in these middle-aged obese diabetic mice, which are associated with the improved islet ?-cell survival and mass. In the in vitro studies, baicalein significantly augmented GSIS and promoted viability of insulin-secreting cells and human islets cultured either in the basal medium or under chronic hyperlipidemic condition. These results demonstrate that baicalein may be a naturally occurring antidiabetic agent by directly modulating pancreatic ?-cell function. PMID:25147566

  16. Improvement of skin wound healing in diabetic mice by kinin B2 receptor blockade.

    PubMed

    Desposito, Dorinne; Chollet, Catherine; Taveau, Christopher; Descamps, Vincent; Alhenc-Gelas, François; Roussel, Ronan; Bouby, Nadine; Waeckel, Ludovic

    2016-01-01

    Impaired skin wound healing is a major medical problem in diabetic subjects. Kinins exert a number of vascular and other actions limiting organ damage in ischaemia or diabetes, but their role in skin injury is unknown. We investigated, through pharmacological manipulation of bradykinin B1 and B2 receptors (B1R and B2R respectively), the role of kinins in wound healing in non-diabetic and diabetic mice. Using two mouse models of diabetes (streptozotocin-induced and db/db mice) and non-diabetic mice, we assessed the effect of kinin receptor activation or inhibition by subtype-selective pharmacological agonists (B1R and B2R) and antagonist (B2R) on healing of experimental skin wounds. We also studied effects of agonists and antagonist on keratinocytes and fibroblasts in vitro. Levels of Bdkrb1 (encoding B1R) and Bdkrb2 (encoding B2R) mRNAs increased 1-2-fold in healthy and wounded diabetic skin compared with in non-diabetic skin. Diabetes delayed wound healing. The B1R agonist had no effect on wound healing. In contrast, the B2R agonist impaired wound repair in both non-diabetic and diabetic mice, inducing skin disorganization and epidermis thickening. In vitro, B2R activation unbalanced fibroblast/keratinocyte proliferation and increased keratinocyte migration. These effects were abolished by co-administration of B2R antagonist. Interestingly, in the two mouse models of diabetes, the B2R antagonist administered alone normalized wound healing. This effect was associated with the induction of Ccl2 (encoding monocyte chemoattractant protein 1)/Tnf (encoding tumour necrosis factor ?) mRNAs. Thus stimulation of kinin B2 receptor impairs skin wound healing in mice. B2R activation occurs in the diabetic skin and delays wound healing. B2R blockade improves skin wound healing in diabetic mice and is a potential therapeutic approach to diabetic ulcers. PMID:26443866

  17. Influences of crude extract of tea leaves, Camellia sinensis, on streptozotocin diabetic male albino mice

    PubMed Central

    Al-Attar, Atef M.; Zari, Talal A.

    2010-01-01

    Natural remedies from medicinal plants are considered to be effective and safe alternative treatment for diabetes mellitus. The aim of the present study was to investigate the hypoglycemic activity of the crude tea leaves extract on streptozotocin (STZ)-induced diabetic mice. The average body weight of animals with diabetes and their percentage changes of body weight gain after 15 and 30 days were significantly lower than that of the normal control mice. In diabetic mice, supplementation with tea leaves extract decreased the loss of body weight. After 15 and 30 days, significant increases in the levels of serum glucose, triglycerides, cholesterol, creatinine, urea, uric acid, glutamic pyruvic acid transaminase (GPT) and glutamic oxaloacetic acid transaminase (GOT) were noted in STZ-diabetic mice fed with normal diet. Also, the values of total protein in this group were statistically declined after 15 and 30 days. The levels of serum glucose and GPT were significantly elevated after 15 and 30 days in diabetic mice supplemented with tea leaves extract. Moreover, the level of serum GOT was notably increased after 30 days. Insignificant alterations were observed in the levels of serum triglycerides, cholesterol, total protein, creatinine, urea and uric acid in diabetic mice supplemented with tea leaves extract. Thus, the present results have shown that tea leaves extract has the antihyperglycemic, antihyperlipidemic, and antihyperproteinemic effects and consequently may alleviate liver and kidney damage associated with STZ-induced diabetes in mice. PMID:23961092

  18. Anti-Diabetic and Hepato-Renal Protective Effects of Ziyuglycoside II Methyl Ester in Type 2 Diabetic Mice

    PubMed Central

    Son, Dong Ju; Hwang, Seock Yeon; Kim, Myung-Hyun; Park, Un Kyu; Kim, Byoung Soo

    2015-01-01

    Type 2 diabetes is a metabolic disorder caused by abnormal carbohydrate metabolism, and closely associated with abnormal lipid metabolism and hepato-renal dysfunction. This study investigated the anti-diabetic and hepato-renal protective properties of ziyuglycoside I (ZG01) derivative on type 2 diabetes. ZG01 was isolated from roots of Sanguisorba officinalis and chemically modified by deglycosylation and esterification to obtained ziyuglycoside II methyl ester (ZG02-ME). Here, we showed that ZG02-ME has stronger anti-diabetic activity than the original compound (ZG01) through decreasing blood glucose, glycated hemoglobin (HbA1c), and insulin levels in a mouse model of type 2 diabetes (db/db mice). We further found that ZG02-ME treatment effectively ameliorated serum insulin, leptin and C-peptide levels, which are key metabolic hormones, in db/db mice. In addition, we showed that elevated basal blood lipid levels were decreased by ZG02-ME treatment in db/db mice. Furthermore, treatment of ZG02-ME significantly decreased serum AST, ALT, BUN, creatinine, and liver lipid peroxidation in db/db mice. These results demonstrated that compared to ZG01, chemically modified ZG02-ME possess improved anti-diabetic properties, and has hepato-renal protective activities in type 2 diabetes. PMID:26198246

  19. ASK1 Inhibitor Halts Progression of Diabetic Nephropathy in Nos3-Deficient Mice.

    PubMed

    Tesch, Greg H; Ma, Frank Y; Han, Yingjie; Liles, John T; Breckenridge, David G; Nikolic-Paterson, David J

    2015-11-01

    p38 mitogen-activated protein kinase (MAPK) signaling promotes diabetic kidney injury. Apoptosis signal-regulating kinase (ASK)1 is one of the upstream kinases in the p38 MAPK-signaling pathway, which is activated by inflammation and oxidative stress, suggesting a possible role for ASK1 in diabetic nephropathy. In this study, we examined whether a selective ASK1 inhibitor can prevent the induction and progression of diabetic nephropathy in mice. Diabetes was induced in hypertensive endothelial nitric oxide synthase (Nos3)-deficient mice by five low-dose streptozotocin (STZ) injections. Groups of diabetic Nos3(-/-) mice received ASK1 inhibitor (GS-444217 delivered in chow) as an early intervention (2-8 weeks after STZ) or late intervention (weeks 8-15 after STZ). Control diabetic and nondiabetic Nos3(-/-) mice received normal chow. Treatment with GS-444217 abrogated p38 MAPK activation in diabetic kidneys but had no effect upon hypertension in Nos3(-/-) mice. Early intervention with GS-444217 significantly inhibited diabetic glomerulosclerosis and reduced renal dysfunction but had no effect on the development of albuminuria. Late intervention with GS-444217 improved renal function and halted the progression of glomerulosclerosis, renal inflammation, and tubular injury despite having no effect on established albuminuria. In conclusion, this study identifies ASK1 as a new therapeutic target in diabetic nephropathy to reduce renal inflammation and fibrosis independent of blood pressure control. PMID:26180085

  20. BAMBI elimination enhances alternative TGF-? signaling and glomerular dysfunction in diabetic mice.

    PubMed

    Fan, Ying; Li, Xuezhu; Xiao, Wenzhen; Fu, Jia; Harris, Ray C; Lindenmeyer, Maja; Cohen, Clemens D; Guillot, Nicolas; Baron, Margaret H; Wang, Niansong; Lee, Kyung; He, John C; Schlondorff, Detlef; Chuang, Peter Y

    2015-06-01

    BMP, activin, membrane-bound inhibitor (BAMBI) acts as a pseudo-receptor for the transforming growth factor (TGF)-? type I receptor family and a negative modulator of TGF-? kinase signaling, and BAMBI(-/-) mice show mild endothelial dysfunction. Because diabetic glomerular disease is associated with TGF-? overexpression and microvascular alterations, we examined the effect of diabetes on glomerular BAMBI mRNA levels. In isolated glomeruli from biopsies of patients with diabetic nephropathy and in glomeruli from mice with type 2 diabetes, BAMBI was downregulated. We then examined the effects of BAMBI deletion on streptozotocin-induced diabetic glomerulopathy in mice. BAMBI(-/-) mice developed more albuminuria, with a widening of foot processes, than BAMBI(+/+) mice, along with increased activation of alternative TGF-? pathways such as extracellular signal-related kinase (ERK)1/2 and Smad1/5 in glomeruli and cortices of BAMBI(-/-) mice. Vegfr2 and Angpt1, genes controlling glomerular endothelial stability, were downmodulated in glomeruli from BAMBI(-/-) mice with diabetes. Incubation of glomeruli from nondiabetic BAMBI(+/+) or BAMBI(-/-) mice with TGF-? resulted in the downregulation of Vegfr2 and Angpt1, effects that were more pronounced in BAMBI(-/-) mice and were prevented by a MEK inhibitor. The downregulation of Vegfr2 in diabetes was localized to glomerular endothelial cells using a histone yellow reporter under the Vegfr2 promoter. Thus, BAMBI modulates the effects of diabetes on glomerular permselectivity in association with altered ERK1/2 and Smad1/5 signaling. Future therapeutic interventions with inhibitors of alternative TGF-? signaling may therefore be of interest in diabetic nephropathy. PMID:25576053

  1. Amelioration of type 1 diabetes following treatment of non-obese diabetic mice with INGAP and lisofylline

    PubMed Central

    Tersey, Sarah A.; Carter, Jeffery D.; Rosenberg, Lawrence; Taylor-Fishwick, David A.; Mirmira, Raghavendra G.; Nadler, Jerry L.

    2014-01-01

    Type 1 diabetes mellitus results from the autoimmune and inflammatory destruction of insulin-producing islet ? cells, rendering individuals devoid of insulin production. Recent studies suggest that combination therapies consisting of anti-inflammatory agents and islet growth-promoting factors have the potential to cause sustained recovery of ? cell mass, leading to amelioration or reversal of type 1 diabetes in mouse models. In this study, we hypothesized that the combination of the anti-inflammatory agent lisofylline (LSF) with an active peptide fragment of islet neogenesis associated protein (INGAP peptide) would lead to remission of type 1 diabetes in the non-obese diabetic (NOD) mouse. We treated groups of spontaneously diabetic NOD mice with combinations of LSF, INGAP peptide, or control saline parenterally for up to 6 weeks. Our results demonstrate that the mice receiving combined treatment with LSF and INGAP peptide exhibited partial remission of diabetes with increased plasma insulin levels. Histologic assessment of pancreata in mice receiving combined therapy revealed the presence of islet insulin staining, increased ? cell replication, and evidence of Pdx1-positivity in ductal cells. By contrast, diabetic animals showed severe insulitis with no detectible insulin or Pdx1 staining. We conclude that the novel combination treatment with LSF and INGAP peptide has the potential to ameliorate hyperglycemia in the setting of established type 1 diabetes via the recovery of endogenous ? cells and warrant further studies. PMID:26473085

  2. Islet remodeling in female mice with spontaneous autoimmune and streptozotocin-induced diabetes.

    PubMed

    Plesner, Annette; Ten Holder, Joris T; Verchere, C Bruce

    2014-01-01

    Islet alpha- and delta-cells are spared autoimmune destruction directed at beta-cells in type 1 diabetes resulting in an apparent increase of non-beta endocrine cells in the islet core. We determined how islet remodeling in autoimmune diabetes compares to streptozotocin (STZ)-induced diabetes. Islet cell mass, proliferation, and immune cell infiltration in pancreas sections from diabetic NOD mice and mice with STZ-induced diabetes was assessed using quantitative image analysis. Serial sections were stained for various beta-cell markers and Ngn3, typically restricted to embryonic tissue, was only upregulated in diabetic NOD mouse islets. Serum levels of insulin, glucagon and GLP-1 were measured to compare hormone levels with respect to disease state. Total pancreatic alpha-cell mass did not change as autoimmune diabetes developed in NOD mice despite the proportion of islet area comprised of alpha- and delta-cells increased. By contrast, alpha- and delta-cell mass was increased in mice with STZ-induced diabetes. Serum levels of glucagon reflected these changes in alpha-cell mass: glucagon levels remained constant in NOD mice over time but increased significantly in STZ-induced diabetes. Increased serum GLP-1 levels were found in both models of diabetes, likely due to alpha-cell expression of prohormone convertase 1/3. Alpha- or delta-cell mass in STZ-diabetic mice did not normalize by replacement of insulin via osmotic mini-pumps or islet transplantation. Hence, the inflammatory milieu in NOD mouse islets may restrict alpha-cell expansion highlighting important differences between these two diabetes models and raising the possibility that increased alpha-cell mass might contribute to the hyperglycemia observed in the STZ model. PMID:25101835

  3. Impact of experimental type 1 diabetes mellitus on systemic and coagulation vulnerability in mice acutely exposed to diesel exhaust particles

    PubMed Central

    2013-01-01

    Background Epidemiological evidence indicates that diabetic patients have increased susceptibility to adverse cardiovascular outcomes related to acute increases in exposures to particulate air pollution. However, mechanisms underlying these effects remain unclear. Methods To evaluate the possible mechanisms underlying these actions, we assessed the systemic effects of diesel exhaust particles (DEP) in control mice, and mice with streptozotocin–induced type 1 diabetes. Four weeks following induction of diabetes, the animals were intratracheally instilled (i.t.) with DEP (0.4 mg/kg) or saline, and several cardiovascular endpoints were measured 24 h thereafter. Results DEP caused leukocytosis and a significant increase in plasma C-reactive protein and 8-isoprostane concentrations in diabetic mice compared to diabetic mice exposed to saline or non-diabetic mice exposed to DEP. The arterial PO2 as well as the number of platelets and the thrombotic occlusion time in pial arterioles assessed in vivo were significantly decreased following the i.t. instillation of DEP in diabetic mice compared to diabetic mice exposed to saline or non-diabetic mice exposed to DEP. Both alanine aminotransferase and aspartate transaminase activities, as well as the plasma concentrations of plasminogen activator inhibitor and von Willebrand factor were significantly increased in DEP-exposed diabetic mice compared to diabetic mice exposed to saline or DEP-exposed non-diabetic mice. The in vitro addition of DEP (0.25-1 ?g/ml) to untreated mouse blood significantly and dose-dependently induced in vitro platelet aggregation, and these effects were exacerbated in blood of diabetic mice. Conclusion This study has shown that systemic and coagulation events are aggravated by type 1 diabetes in mice, acutely exposed to DEP and has described the possible mechanisms for these actions that may also be relevant to the exacerbation of cardiovascular morbidity accompanying particulate air pollution in diabetic patients. PMID:23587270

  4. The Gut Microbiota Modulates Glycaemic Control and Serum Metabolite Profiles in Non-Obese Diabetic Mice

    PubMed Central

    Greiner, Thomas U.; Hyötyläinen, Tuulia; Knip, Mikael; Bäckhed, Fredrik; Oreši?, Matej

    2014-01-01

    Islet autoimmunity in children who later progress to type 1 diabetes is preceded by dysregulated serum metabolite profiles, but the origin of these metabolic changes is unknown. The gut microbiota affects host metabolism and changes in its composition contribute to several immune-mediated diseases; however, it is not known whether the gut microbiota is involved in the early metabolic disturbances in progression to type 1 diabetes. We rederived non-obese diabetic (NOD) mice as germ free to explore the potential role of the gut microbiota in the development of diabetic autoimmunity and to directly investigate whether the metabolic profiles associated with the development of type 1 diabetes can be modulated by the gut microbiota. The absence of a gut microbiota in NOD mice did not affect the overall diabetes incidence but resulted in increased insulitis and levels of interferon gamma and interleukin 12; these changes were counterbalanced by improved peripheral glucose metabolism. Furthermore, we observed a markedly increased variation in blood glucose levels in the absence of a microbiota in NOD mice that did not progress to diabetes. Additionally, germ-free NOD mice had a metabolite profile similar to that of pre-diabetic children. Our data suggest that germ-free NOD mice have reduced glycaemic control and dysregulated immunologic and metabolic responses. PMID:25390735

  5. Kinin B1 Receptor Deletion Affects Bone Healing in Type 1 Diabetic Mice.

    PubMed

    Cignachi, Natália P; Pesquero, João B; Oliveira, Rogério B; Etges, Adriana; Campos, Maria M

    2015-12-01

    The effects of kinin B1 receptor (B1 R) deletion were examined on femur bone regeneration in streptozotocin (STZ)-type 1 diabetes. Diabetes induction in wild-type C57/BL6 (WTC57BL6) mice led to decrease in body weight and hyperglycemia, compared to the non-diabetic group of the same strain. The lack of B1 R did not affect STZ-elicited body weight loss, but partially prevented hyperglycemia. Diabetic mice had a clear delay in bone regeneration, and displayed large areas of loose connective tissue within the defects, with a reduced expression of the mineralization-related protein osteonectin, when compared to the non-diabetic WTC57/BL6. The non-diabetic and diabetic B1 R knockout (B1 RKO) mice had bone regeneration levels and osteonectin expression comparable to that seen in control WTC57/BL6 mice. WTC57/BL6 STZ-diabetic mice also showed a marked reduction of collagen contents, with increased immunolabeling for the apoptosis marker caspase-3, whereas diabetic B1 RKO had collagen levels and caspase-3 activity comparable to those observed in non-diabetic WTC57/BL6 or B1 RKO mice. No significant difference was detected in the number of tartrate-resistant acid phosphatase (TRAP)-stained cells, or in RANK/RANKL/OPG system immunolabeling throughout the experimental groups. Data bring novel evidence on the relevance of kinin B1 R under type 1 diabetes with regards to its role in bone regeneration. PMID:25969420

  6. O-GlcNAcase overexpression reverses coronary endothelial cell dysfunction in type 1 diabetic mice.

    PubMed

    Makino, Ayako; Dai, Anzhi; Han, Ying; Youssef, Katia D; Wang, Weihua; Donthamsetty, Reshma; Scott, Brian T; Wang, Hong; Dillmann, Wolfgang H

    2015-11-01

    Cardiovascular disease is the primary cause of morbidity and mortality in diabetes, and endothelial dysfunction is commonly seen in these patients. Increased O-linked N-acetylglucosamine (O-GlcNAc) protein modification is one of the central pathogenic features of diabetes. Modification of proteins by O-GlcNAc (O-GlcNAcylation) is regulated by two key enzymes: ?-N-acetylglucosaminidase [O-GlcNAcase (OGA)], which catalyzes the reduction of protein O-GlcNAcylation, and O-GlcNAc transferase (OGT), which induces O-GlcNAcylation. However, it is not known whether reducing O-GlcNAcylation can improve endothelial dysfunction in diabetes. To examine the effect of endothelium-specific OGA overexpression on protein O-GlcNAcylation and coronary endothelial function in diabetic mice, we generated tetracycline-inducible, endothelium-specific OGA transgenic mice, and induced OGA by doxycycline administration in streptozotocin-induced type 1 diabetic mice. OGA protein expression was significantly decreased in mouse coronary endothelial cells (MCECs) isolated from diabetic mice compared with control MCECs, whereas OGT protein level was markedly increased. The level of protein O-GlcNAcylation was increased in diabetic compared with control mice, and OGA overexpression significantly decreased the level of protein O-GlcNAcylation in MCECs from diabetic mice. Capillary density in the left ventricle and endothelium-dependent relaxation in coronary arteries were significantly decreased in diabetes, while OGA overexpression increased capillary density to the control level and restored endothelium-dependent relaxation without changing endothelium-independent relaxation. We found that connexin 40 could be the potential target of O-GlcNAcylation that regulates the endothelial functions in diabetes. These data suggest that OGA overexpression in endothelial cells improves endothelial function and may have a beneficial effect on coronary vascular complications in diabetes. PMID:26269457

  7. Optical cryo-imaging of kidney mitochondrial redox state in diabetic mice models

    NASA Astrophysics Data System (ADS)

    Maleki, S.; Sepehr, R.; Staniszewski, K.; Sheibani, N.; Sorenson, C. M.; Ranji, M.

    2012-03-01

    Oxidative stress (OS), which increases during diabetes, exacerbates the development and progression of diabetes complications including renal vascular and proximal tubule cell dysfunction. The objective of this study was to investigate the changes in the metabolic state of the tissue in diabetic mice kidneys using fluorescence imaging. Mitochondrial metabolic coenzymes NADH (Nicotinamide Adenine Dinucleotide), and FADH-2 (Flavin Adenine Dinucleotide) are autofluorescent and can be monitored without exogenous labels by optical techniques. The ratio of the fluorescence intensity of these fluorophores, (NADH/FAD), called the NADH redox ratio (RR), is a marker of metabolic state of a tissue. We examined mitochondrial redox states of kidneys from diabetic mice, Akita/+ and its control wild type (WT) for a group of 8- and 12-week-old mice. Average intensity and histogram of maximum projected images of FAD, NADH, and NADH RR were calculated for each kidney. Our results indicated a 17% decrease in the mean NADH RR of the kidney from 8-week-old mice compared with WT mice and, a 30% decrease in the mean NADH RR of kidney from12-week-old mice compared with WT mice. These results indicated an increase in OS in diabetic animals and its progression over time. Thus, NADH RR can be used as a hallmark of OS in diabetic kidney allowing temporal identification of oxidative state.

  8. Dietary Flavonol Epicatechin Prevents the Onset of Type 1 Diabetes in Non-obese Diabetic (NOD) Mice

    PubMed Central

    Fu, Zhuo; Yuskavage, Julia; Liu, Dongmin

    2013-01-01

    Type 1 diabetes (T1D) is an autoimmune disease characterized by the selective destruction of pancreatic ?-cells. Although successful islet transplantation provides a promising treatment, high cost, lack of donor organs, immune-mediated destruction of transplanted islets, and side effects from immunosuppressive drugs greatly limit its uses. Therefore, the search for novel and cost-effective agents that can prevent or ameliorate T1D is extremely important to decrease the burden of T1D. In this study, we discovered that epicatechin (EC, 0.5% in drinking water), a flavonol primarily in cocoa, effectively prevented T1D in non-obese diabetic (NOD) mice. At 32 weeks of age, 66.7% control mice had overt diabetes, whereas only 16.6% EC-treated mice became diabetic. Consistently, EC mice had significantly higher plasma insulin levels but lower glycosylated hemoglobin concentrations compared to control mice. EC had no significant effects on food or water intake and body weight gain in NOD mice, suggesting that EC’s effect was not due to alterations in these variables. Treatment with EC elevates circulating anti-inflammatory cytokine interleukin-10 levels, ameliorates pancreatic insulitis, and improved pancreatic islet mass. These findings demonstrate that EC may be a novel, plant-derived compound capable of preventing T1D by modulating immune function and thereby preserving islet mass. PMID:23578364

  9. Anti-diabetic activity of Vaccinium bracteatum Thunb. leaves' polysaccharide in STZ-induced diabetic mice.

    PubMed

    Wang, Li; Zhang, Ying; Xu, Maochao; Wang, Yingyao; Cheng, Sujiao; Liebrecht, Alex; Qian, Haifeng; Zhang, Hui; Qi, Xiguang

    2013-10-01

    Vaccinium bracteatum Thunb. (VBT) is a traditional Chinese herbal medicine. The anti-diabetic activity of VBT leaves' polysaccharide (VBTLP) is studied in this paper. The results indicated VBTLP had a dose-dependent decrease on the blood glucose (BG) level, and the time effect of VBTLP on BG level was also significant. The insulin level of high dose group (HDG) was significantly higher (p<0.05) than that of model control (MC) group. Compared to MC, HDG and lose dose group (LDG) had significantly lower (p<0.05) TC and LDL-C levels, however, TG and HDL-C levels are similar. Compared to non-diabetic control (NC), HDG and LDG had similar plasma lipid levels except for higher LDL-C level. Although body weights of LDG and HDG were significant lower (p<0.05) than that of NC from week 2 to week 6, they were similar to that of PC. The results indicate VBTLP possesses a potential hypoglycemic effect in streptozotocin-induced diabetic mice. PMID:23916645

  10. Myocardial fatty acid metabolism in diabetic mice with 125I-BMIPP.

    PubMed

    Oshima, M; Higashi, S; Kikuchi, Y; Shirai, T; Yokokawa, T; Kaminaga, T; Yasukochi, H; Furui, S

    1998-06-01

    In patients with diabetes mellitus, the existence of diabetic cardiomyopathy was substantiated. This study was undertaken to evaluate the myocardiac fatty acid metabolism of diabetic mice (n = 21) and controls (n = 21) in 125I-BMIPP in fasted and unfasted states. 125I-BMIPP of 370 kBq was given and thirty minutes later, animals from both groups were killed. Samples of hearts, liver and other organs were removed, weighed and then counted in a scintillation counter. The percent injected dose/g of hearts of diabetic mice was significantly reduced compared to controls in unfasted (p < 0.05) and fasted (p < 0.01) groups. These findings may reflect impaired fatty acid utilization of the hearts in diabetic mice compared to controls. PMID:9673713

  11. Heat-killed yeast protects diabetic ketoacidotic-steroid treated mice from pulmonary mucormycosis.

    PubMed

    Luo, Guanpingsheng; Gebremariam, Teclegiorgis; Clemons, Karl V; Stevens, David A; Ibrahim, Ashraf S

    2014-06-17

    Previous studies have shown that vaccination with heat-killed yeast, Saccharomyces cerevisiae (HKY), protects mice against systemic candidiasis, aspergillosis, cryptococcosis or coccidioidomycosis. Here we sought to define the potential use of HKY as a vaccine to protect mice from mucormycosis. Mice were vaccinated with different regimens of HKY prior to induction of diabetes. Diabetic ketoacidotic (DKA) mice were then treated with steroids prior to intratracheal challenge with Rhizopus oryzae. All regimens of HKY vaccine improved survival of DKA mice and reduced fungal burden in the primary target organ, lungs, as determined by qPCR. Furthermore, compared to mice vaccinated with diluent, vaccination with HKY substantially increased the mouse immune response as determined by detection of increased anti-Rhizopus antibody titers. Our results show that HKY protects steroid-treated DKA mice from pulmonary R. oryzae infection. Considering its demonstrated efficacy against other fungal infections, HKY is a promising candidate for development as a panfungal vaccine. PMID:24814556

  12. Divergent effects of oxytocin treatment of obese diabetic mice on adiposity and diabetes.

    PubMed

    Altirriba, Jordi; Poher, Anne-Laure; Caillon, Aurélie; Arsenijevic, Denis; Veyrat-Durebex, Christelle; Lyautey, Jacqueline; Dulloo, Abdul; Rohner-Jeanrenaud, Françoise

    2014-11-01

    Oxytocin has been suggested as a novel therapeutic against obesity, because it induces weight loss and improves glucose tolerance in diet-induced obese rodents. A recent clinical pilot study confirmed the oxytocin-induced weight-reducing effect in obese nondiabetic subjects. Nevertheless, the mechanisms involved and the impact on the main comorbidity associated with obesity, type 2 diabetes, are unknown. Lean and ob/ob mice (model of obesity, hyperinsulinemia, and diabetes) were treated for 2 weeks with different doses of oxytocin, analogues with longer half-life (carbetocin) or higher oxytocin receptor specificity ([Thr4,Gly7]-oxytocin). Food and water intake, body weight, and glycemia were measured daily. Glucose, insulin, and pyruvate tolerance, body composition, several hormones, metabolites, gene expression, as well as enzyme activities were determined. Although no effect of oxytocin on the main parameters was observed in lean mice, the treatment dose-dependently reduced food intake and body weight gain in ob/ob animals. Carbetocin behaved similarly to oxytocin, whereas [Thr4,Gly7]-oxytocin (TGOT) and a low oxytocin dose decreased body weight gain without affecting food intake. The body weight gain-reducing effect was limited to the fat mass only, with decreased lipid uptake, lipogenesis, and inflammation, combined with increased futile cycling in abdominal adipose tissue. Surprisingly, oxytocin treatment of ob/ob mice was accompanied by a worsening of basal glycemia and glucose tolerance, likely due to increased corticosterone levels and stimulation of hepatic gluconeogenesis. These results impose careful selection of the conditions in which oxytocin treatment should be beneficial for obesity and its comorbidities, and their relevance for human pathology needs to be determined. PMID:25157455

  13. Arsenic induces diabetic effects through beta-cell dysfunction and increased gluconeogenesis in mice

    PubMed Central

    Liu, Su; Guo, Xuechao; Wu, Bing; Yu, Haiyan; Zhang, Xuxiang; Li, Mei

    2014-01-01

    Arsenic as a potential risk factor for type 2 diabetes has been received attention recently. However, the roles of arsenic on development of diabetes are unclear. In this study, we compared the influences of inorganic arsenic (iAs) on normal and diabetic mice by systems toxicology approaches. Although iAs exposure did not change glucose tolerance in normal mice, it caused the pancreatic ?-cell dysfunction and increased gluconeogenesis and oxidative damages in liver. However, iAs exposure worsened the glucose tolerance in diabetic mice, which might be due to increased gluconeogenesis and impairment of pancreatic ?-cell function. It is interesting that iAs exposure could improve the insulin sensitivity based on the insulin tolerance testing by the activation of glucose uptake-related genes and enzymes in normal and diabetic individuals. Our data suggested that iAs exposure could cause pre-diabetic effects by altering the lipid metabolism, gluconeogenesis and insulin secretion in normal individual, and worsen diabetic effects in diabetes individual by these processes. Insulin resistance might be not the reason of diabetic effects caused by iAs, indicating that mechanism of the diabetogenic effects of iAs exposure is different from the mechanism associated with traditional risk factors (such as obesity)-reduced type 2 diabetes. PMID:25367288

  14. Arsenic induces diabetic effects through beta-cell dysfunction and increased gluconeogenesis in mice

    NASA Astrophysics Data System (ADS)

    Liu, Su; Guo, Xuechao; Wu, Bing; Yu, Haiyan; Zhang, Xuxiang; Li, Mei

    2014-11-01

    Arsenic as a potential risk factor for type 2 diabetes has been received attention recently. However, the roles of arsenic on development of diabetes are unclear. In this study, we compared the influences of inorganic arsenic (iAs) on normal and diabetic mice by systems toxicology approaches. Although iAs exposure did not change glucose tolerance in normal mice, it caused the pancreatic ?-cell dysfunction and increased gluconeogenesis and oxidative damages in liver. However, iAs exposure worsened the glucose tolerance in diabetic mice, which might be due to increased gluconeogenesis and impairment of pancreatic ?-cell function. It is interesting that iAs exposure could improve the insulin sensitivity based on the insulin tolerance testing by the activation of glucose uptake-related genes and enzymes in normal and diabetic individuals. Our data suggested that iAs exposure could cause pre-diabetic effects by altering the lipid metabolism, gluconeogenesis and insulin secretion in normal individual, and worsen diabetic effects in diabetes individual by these processes. Insulin resistance might be not the reason of diabetic effects caused by iAs, indicating that mechanism of the diabetogenic effects of iAs exposure is different from the mechanism associated with traditional risk factors (such as obesity)-reduced type 2 diabetes.

  15. Bisphosphonate treatment of type I diabetic mice prevents early bone loss but accentuates suppression of bone formation.

    PubMed

    Coe, Lindsay M; Tekalur, Srinivasan Arjun; Shu, Yutian; Baumann, Melissa J; McCabe, Laura R

    2015-08-01

    Type I (T1) diabetes is an autoimmune and metabolic disease associated with bone loss. Previous studies demonstrate that T1-diabetes decreases osteoblast activity and viability. Bisphosphonate therapy, commonly used to treat osteoporosis, is demonstrated to inhibit osteoclast activity as well as osteoblast apoptosis. Therefore, we examined the effect of weekly alendronate treatments on T1-diabetes induced osteoblast apoptosis and bone loss. Bone TUNEL assays identified that alendronate therapy prevents the diabetes-induced osteoblast death observed during early stages of diabetes development. Consistent with this, alendronate treatment for 40 days was able to prevent diabetes-induced trabecular bone loss. Alendronate was also able to reduce marrow adiposity in both control diabetic mice compared to untreated mice. Mechanical testing indicated that 40 days of alendronate treatment increased bone stiffness but decreased the work required for fracture in T1-diabetic and alendronate treated mice. Of concern at this later time point, bone formation rate and osteoblast markers, which were already decreased in diabetic mice, were further suppressed in alendronate-treated diabetic mice. Taken together, our results suggest that short-term alendronate treatment can prevent T1-diabetes-induced bone loss in mice, possibly in part by inhibiting diabetes onset associated osteoblast death, while longer treatment enhanced bone density but at the cost of further suppressing bone formation in diabetic mice. PMID:25641511

  16. Daintain/AIF-1 (Allograft Inflammatory Factor-1) accelerates type 1 diabetes in NOD mice

    SciTech Connect

    Zhao, Yan-Ying; Huang, Xin-Yuan; Chen, Zheng-Wang

    2012-10-26

    Highlights: Black-Right-Pointing-Pointer Daintain/AIF-1 is over-expressed in the blood of NOD mice suffering from insulitis. Black-Right-Pointing-Pointer Daintain/AIF-1 stimulates white blood cell proliferation in NOD mice. Black-Right-Pointing-Pointer Daintain/AIF-1 increases blood glucose levels and triggers type 1 diabetes. Black-Right-Pointing-Pointer Daintain/AIF-1 accelerates insulitis, while its antibody prevents insulitis. Black-Right-Pointing-Pointer Daintain/AIF-1 enhances the levels of nitric oxide in the pancreases of NOD mice. -- Abstract: A large body of experimental evidence suggests that cytokines trigger pancreatic {beta}-cell death in type 1 diabetes mellitus. Daintain/AIF-1 (Allograft Inflammatory Factor-1), a specific marker for activated macrophages, is accumulated in the pancreatic islets of pre-diabetic BB rats. In the present study, we demonstrate that daintain/AIF-1 is released into blood and the levels of daintain/AIF-1 in the blood of type 1 diabetes-prone non-obese diabetic (NOD) mice suffering from insulitis are significantly higher than that in healthy NOD mice. When injected intravenously into NOD mice, daintain/AIF-1 stimulates white blood cell proliferation, increases the concentrations of blood glucose, impairs insulin expression, up-regulates nitric oxide (NO) production in pancreases and accelerates diabetes in NOD mice, while the antibody against daintain/AIF-1 delays or prevents insulitis in NOD mice. These results imply daintain/AIF-1 triggers type 1 diabetes probably via arousing immune cells activation and induction of NO production in pancreas of NOD mice.

  17. Tumor necrosis factor inhibition increases the revascularization of ischemic hind-limbs in diabetic mice.

    PubMed

    Assiri, Adel M A; El-Baz, Hatim A; Amin, Ali H

    2015-10-01

    Tumor necrosis factor (TNF) is first identified as a mediator of lethal endotoxin poisoning. The anti-TNF therapy in the treatment of rheumatoid arthritis is based on the recognition of the role of TNF as the master regulator. Type II diabetes is characterized with altered stem cells and reduced vasculogenesis. Therefore, we aimed to determine if TNF inhibitor would improve vasculogenesis in ischemic hind-limbs of diabetic mice. Fifty male type 2 diabetic and their control (8-10 weeks old mice) were used, and ischemia was induced in the hind-limbs of all mice for 28 days. Vessel density was assessed by high-definition microangiography at the end of the treatment period. After 4 weeks, vessel density displayed no difference between the ischemic and the non-ischemic legs in control mice. However, in diabetic mice, the ischemic hind-limb vessel density was significantly decreased. Interestingly, diabetic mice displayed a significant improved vasculogenesis when treated with TNF inhibitor. Moreover, this data was confirmed by capillary density determined by immunostaining. TNF inhibitors are able to improve the formation of microvessels in response to ischemia in type 2 diabetes. PMID:26026701

  18. Obesity and genetics regulate microRNAs in islets, liver, and adipose of diabetic mice

    E-print Network

    Yandell, Brian S.

    Obesity and genetics regulate microRNAs in islets, liver, and adipose of diabetic mice Enpeng Zhao the relationship between miRNA regulation and obesity- induced diabetes, we quantitatively profiled approximatelyRNAs in each tissue showing significant changes in response to genetic obesity. Furthermore, several mi

  19. Urtica dioica leaves modulates muscarinic cholinergic system in the hippocampus of streptozotocin-induced diabetic mice.

    PubMed

    Patel, Sita Sharan; Parashar, Arun; Udayabanu, Malairaman

    2015-06-01

    Diabetes mellitus is a chronic metabolic disorder and has been associated with cognitive dysfunction. In our earlier study, chronic Urtica dioica (UD) treatment significantly ameliorated diabetes induced associative and spatial memory deficit in mice. The present study was designed to explore the effect of UD leaves extract on muscarinic cholinergic system, which has long been known to be involved in cognition. Streptozotocin (STZ) (50 mg/kg, i.p., consecutively for 5 days) was used to induce diabetes followed by treatment with UD extract (50 mg/kg, oral) or rosiglitazone (5 mg/kg, oral) for 8 weeks. STZ-induced diabetic mice showed significant reduction in hippocampal muscarinic acetylcholine receptor-1 and choline acetyltransferase expressions. Chronic diabetes significantly up-regulated the protein expression of acetylcholinesterase associated with oxidative stress in hippocampus. Besides, STZ-induced diabetic mice showed hypolocomotion with up-regulation of muscarinic acetylcholine receptor-4 expression in striatum. Chronic UD treatment significantly attenuated the cholinergic dysfunction and oxidative stress in the hippocampus of diabetic mice. UD had no effect on locomotor activity and muscarinic acetylcholine receptor-4 expression in striatum. In conclusion, UD leaves extract has potential to reverse diabetes mediated alteration in muscarinic cholinergic system in hippocampus and thereby improve memory functions. PMID:25514862

  20. Protective Effects of MDG-1, a Polysaccharide from Ophiopogon japonicus on Diabetic Nephropathy in Diabetic KKA(y) Mice.

    PubMed

    Wang, Yuan; Shi, Lin-Lin; Wang, Ling-Yi; Xu, Jin-Wen; Feng, Yi

    2015-01-01

    Ophiopogon japonicus is a traditional Chinese medicine that might be effective for treating type 2 diabetes. Recent research confirmed that MDG-1, a polysaccharide from O. japonicas, activates the PI3K/Akt signaling pathway and improves insulin sensitivity in a diabetic KKA(y) mouse model, but little is known about its effects on diabetic nephropathy. In this study, KKA(y) mice were orally administered distilled water (control group), MDG-1, or rosiglitazone for 12 weeks. Blood glucose levels were tested every two weeks for the fed mice. At 6 and 12 weeks, blood samples were collected for biochemical examination. At the end of the experiment, all kidney tissues were collected for histological examination and western blot analysis. Results show that MDG-1 (300 mg/kg) significantly decreased the levels of blood glucose, triglycerides, blood urine nitrogen and albumin, and significantly inhibited the expression of transforming growth factor-beta 1 and connective tissue growth factor. Moreover, MDG-1 could alleviate glomerular mesangial expansion and tubulointerstitial fibrosis in the diabetic mice, as confirmed by histopathological examination. These data indicated that MDG-1 ameliorates renal disease in diabetic mice by reducing hyperglycemia, hyperinsulinemia, and hyperlipidemia, and by inhibiting intracellular signaling pathways. PMID:26393572

  1. Protective Effects of MDG-1, a Polysaccharide from Ophiopogon japonicus on Diabetic Nephropathy in Diabetic KKAy Mice

    PubMed Central

    Wang, Yuan; Shi, Lin-Lin; Wang, Ling-Yi; Xu, Jin-Wen; Feng, Yi

    2015-01-01

    Ophiopogon japonicus is a traditional Chinese medicine that might be effective for treating type 2 diabetes. Recent research confirmed that MDG-1, a polysaccharide from O. japonicas, activates the PI3K/Akt signaling pathway and improves insulin sensitivity in a diabetic KKAy mouse model, but little is known about its effects on diabetic nephropathy. In this study, KKAy mice were orally administered distilled water (control group), MDG-1, or rosiglitazone for 12 weeks. Blood glucose levels were tested every two weeks for the fed mice. At 6 and 12 weeks, blood samples were collected for biochemical examination. At the end of the experiment, all kidney tissues were collected for histological examination and western blot analysis. Results show that MDG-1 (300 mg/kg) significantly decreased the levels of blood glucose, triglycerides, blood urine nitrogen and albumin, and significantly inhibited the expression of transforming growth factor-beta 1 and connective tissue growth factor. Moreover, MDG-1 could alleviate glomerular mesangial expansion and tubulointerstitial fibrosis in the diabetic mice, as confirmed by histopathological examination. These data indicated that MDG-1 ameliorates renal disease in diabetic mice by reducing hyperglycemia, hyperinsulinemia, and hyperlipidemia, and by inhibiting intracellular signaling pathways. PMID:26393572

  2. Effect of Tongxinluo on nerve regeneration in mice with diabetic peripheral neuropathy.

    PubMed

    Li, X; Zhang, J; Zhao, W; Yang, H; Ma, J; Qi, Y; Wu, S

    2015-01-01

    Diabetic peripheral neuropathy (DPN) is a common complication of diabetes. This study aims to investigate the effects of Tongxinluo on the nerve regeneration in diabetic peripheral neuropathy mice. Forty Specefic Pathogen Free (SPF) male KK/Upj—Ay mice were divided into diabetes group, diabetes with high dose Tongxinluo (4g/kg) (D+H), diabetes with mid dose Tongxinluo (2g/kg) (D+M), and diabetes with low dose Tongxinluo (1g/kg) (D+L) groups. Fasting blood glucose (FPG), heat pain threshold, motor nerve conduction velocity (MNCV), insulin—like growth factor—1 (IGF1), activator protein 1 (c—fos), nerve growth factor (NGF), and basic fibroblast growth factor (BFGF) were measured. Results indicated that FPG of diabetes group was significantly higher than that of control group. Heat pain threshold and MNCV were significantly lowered in diabetes group. Expression levels of IGF1, NGF and BFGF were significantly lower than that of control, whereas c—fos expression was significantly higher than that of control group. Tongxinluo treatment (D+M and D+H) significantly up—regulated heat pain threshold, MNCV, and IGF1, NGF and BFGF expression, but decreased c—fos expresson when compared to that of diabetes group. In conclusion, Tongxinluo can ameliorate diabetic peripheral neuropathy, improve MNCV, and promote nerve regeneration. The underlying mechanism needs to be further elucidated. PMID:26522065

  3. Protective Effects of Red Guava on Inflammation and Oxidative Stress in Streptozotocin-Induced Diabetic Mice.

    PubMed

    Li, Pei-Ying; Hsu, Cheng-Chin; Yin, Mei-Chin; Kuo, Yueh-Hsiung; Tang, Feng-Yao; Chao, Che-Yi

    2015-01-01

    Diabetes is an important chronic disease and the 4th leading cause of death in Taiwan. Hyperglycemia-induced oxidative and inflammatory damage are the main causes of chronic complications in diabetic patients. The red guava (red-fleshed guava cultivar of Psidium guajava L.) is a tropical fruit belonging to the Myrtaceae family and an important commercial crop in Taiwan. In this study, the protective effects of a diet containing red guava on inflammation and oxidative stress in streptozotocin (STZ)-induced diabetic mice were examined. The experimental group was divided into seven subgroups: normal (N), diabetes mellitus (DM), diabetes + red guava 1% (L), 2% (M), and 5% (H), diabetes + 5% red guava + anti-diabetic rosiglitazone (HR), and diabetes + anti-diabetic rosiglitazone (R). The mice were fed for 8 weeks and sacrificed by decapitation. Compared with the DM group, the experimental groups with diets containing red guava as well as rosiglitazone all showed significant improvements in blood glucose control, insulin resistance, creatinine, blood urea nitrogen, triglycerides, non-esterified fatty acids, cholesterol, c-reactive protein, TNF-?, and IL-10. Furthermore, the expression of inflammatory proteins, such as iNOS and NF-?B, was suppressed via activated PPAR?, and the expression levels of GPx3 and ACO increased. In summary, red guava can significantly suppress inflammatory and oxidative damage caused by diabetes and alleviate diabetic symptoms; thus, it exerts protective effects and has potential applications for the development of a dietary supplement. PMID:26703532

  4. Acute Versus Progressive Onset of Diabetes in NOD Mice: Potential Implications for Therapeutic Interventions in Type 1 Diabetes.

    PubMed

    Mathews, Clayton E; Xue, Song; Posgai, Amanda; Lightfoot, Yaima L; Li, Xia; Lin, Andrea; Wasserfall, Clive; Haller, Michael J; Schatz, Desmond; Atkinson, Mark A

    2015-11-01

    Most natural history models for type 1 diabetes (T1D) propose that overt hyperglycemia results after a progressive loss of insulin-secreting ?-cell mass and/or function. To experimentally address this concept, we prospectively determined morning blood glucose measurements every other day in multiple cohorts (total n = 660) of female NOD/ShiLtJ mice starting at 8 weeks of age until diabetes onset or 26 weeks of age. Consistent with this notion, a majority of mice that developed diabetes (354 of 489 [72%]) displayed a progressive increase in blood glucose with transient excursions >200 mg/dL, followed by acute and persistent hyperglycemia at diabetes onset. However, 135 of the 489 (28%) diabetic animals demonstrated normal glucose values followed by acute (i.e., sudden) hyperglycemia. Interestingly, diabetes onset occurred earlier in mice with acute versus progressive disease onset (15.37 ± 0.3207 vs. 17.44 ± 0.2073 weeks of age, P < 0.0001). Moreover, the pattern of onset (i.e., progressive vs. acute) dramatically influenced the ability to achieve reversal of T1D by immunotherapeutic intervention, with increased effectiveness observed in situations of a progressive deterioration in euglycemia. These studies highlight a novel natural history aspect in this animal model, one that may provide important guidance for the selection of subjects participating in human trials seeking disease reversal. PMID:26216853

  5. Adipose-Derived Stem Cells From Diabetic Mice Show Impaired Vascular Stabilization in a Murine Model of Diabetic Retinopathy

    PubMed Central

    Cronk, Stephen M.; Kelly-Goss, Molly R.; Ray, H. Clifton; Mendel, Thomas A.; Hoehn, Kyle L.; Bruce, Anthony C.; Dey, Bijan K.; Guendel, Alexander M.; Tavakol, Daniel N.; Herman, Ira M.; Yates, Paul A.

    2015-01-01

    Diabetic retinopathy is characterized by progressive vascular dropout with subsequent vision loss. We have recently shown that an intravitreal injection of adipose-derived stem cells (ASCs) can stabilize the retinal microvasculature, enabling repair and regeneration of damaged capillary beds in vivo. Because an understanding of ASC status from healthy versus diseased donors will be important as autologous cellular therapies are developed for unmet clinical needs, we took advantage of the hyperglycemic Akimba mouse as a preclinical in vivo model of diabetic retinopathy in an effort aimed at evaluating therapeutic efficacy of adipose-derived stem cells (mASCs) derived either from healthy, nondiabetic or from diabetic mice. To these ends, Akimba mice received intravitreal injections of media conditioned by mASCs or mASCs themselves, subsequent to development of substantial retinal capillary dropout. mASCs from healthy mice were more effective than diabetic mASCs in protecting the diabetic retina from further vascular dropout. Engrafted ASCs were found to preferentially associate with the retinal vasculature. Conditioned medium was unable to recapitulate the vasoprotection seen with injected ASCs. In vitro diabetic ASCs showed decreased proliferation and increased apoptosis compared with healthy mASCs. Diabetic ASCs also secreted less vasoprotective factors than healthy mASCs, as determined by high-throughput enzyme-linked immunosorbent assay. Our findings suggest that diabetic ASCs are functionally impaired compared with healthy ASCs and support the utility of an allogeneic injection of ASCs versus autologous or conditioned media approaches in the treatment of diabetic retinopathy. PMID:25769654

  6. Improvement of cognitive impairment in female type 2 diabetes mellitus mice by spironolactone.

    PubMed

    Sakata, Akiko; Mogi, Masaki; Iwanami, Jun; Tsukuda, Kana; Min, Li-Juan; Jing, Fei; Ohshima, Kousei; Ito, Masaharu; Horiuchi, Masatsugu

    2012-03-01

    Patients with type 2 diabetes mellitus (T2DM) exhibit more severe cognitive decline in females compared with males; however, the preventive approach to this gender-specific cognitive decline is still an enigma. Spironolactone is a potassium-sparing diuretic that also acts as an androgen receptor antagonist. Here, we investigated whether spironolactone attenuates cognitive impairment observed in female T2DM mice. Adult wild-type (WT) mice and an obese T2DM model, KKAy mice, were employed in this study. Cognitive function was evaluated by the shuttle avoidance test and Morris water maze test. Administration of spironolactone (50 mg/kg per day in chow) had no significant effect on blood pressure, glucose tolerance or insulin resistance. In WT mice, no significant sex difference in cognitive function was observed; however, treatment with spironolactone improved spatial memory in the water maze, especially in female WT mice. Administration of spironolactone markedly improved the cognitive decline in female KKAy mice up to the level in male KKAy mice. Spironolactone treatment also improved cognitive function in ovariectomized-KKAy mice, but failed to improve it in those with administration of estradiol (200 µg/kg per day). In diabetic mice, spironolactone improved impaired cognitive function observed in female mice, suggesting that spironolactone may prevent cognitive impairment associated with diabetes in females clinically. PMID:21729993

  7. Carnosine treatment largely prevents alterations of renal carnosine metabolism in diabetic mice.

    PubMed

    Peters, Verena; Schmitt, Claus P; Zschocke, Johannes; Gross, Marie-Luise; Brismar, Kerstin; Forsberg, Elisabete

    2012-06-01

    Recently, we identified an allelic variant of human carnosinase 1 (CN1) that results in increased enzyme activity and is associated with susceptibility for diabetic nephropathy in humans. Investigations in diabetic (db/db) mice showed that carnosine ameliorates glucose metabolism effectively. We now investigated the renal carnosinase metabolism in db/db mice. Kidney CN1 activity increased with age and was significantly higher in diabetic mice compared to controls. Increased CN1 activity did not affect renal carnosine levels, but anserine concentrations were tenfold lower in db/db mice compared to controls (0.24±0.2 vs. 2.28±0.3 nmol/mg protein in controls; p<0.001). Homocarnosine concentrations in kidney tissue were low in both control and db/db mice (below 0.1 nmol/mg protein, p=n.s.). Carnosine treatment for 4 weeks substantially decreased renal CN1 activity in diabetic mice (0.32±0.3 in non-treated db/db vs. 0.05±0.05 ?mol/mg/h in treated db/db mice; p<0.01) close to normal activities. Renal anserine concentrations increased significantly (0.24±0.2 in non-treated db/db vs. 5.7±1.2 ?mol/mg/h in treated db/db mice; p<0.01), while carnosine concentrations remained unaltered (53±6.4 in non-treated vs. 61±15 nmol/mg protein in treated db/db mice; p=n.s.). Further, carnosine treatment halved proteinuria and reduced vascular permeability to one-fifth in db/db mice. In renal tissue of diabetic mice carnosinase activity is significantly increased and anserine concentrations are significantly reduced compared to controls. Carnosine treatment largely prevents the alterations of renal carnosine metabolism. PMID:21833769

  8. Antihyperglycemic Effect of Ganoderma Lucidum Polysaccharides on Streptozotocin-Induced Diabetic Mice

    PubMed Central

    Li, Fenglin; Zhang, Yiming; Zhong, Zhijian

    2011-01-01

    The current study evaluated the glucose-lowering effect of ganoderma lucidum polysaccharides (Gl-PS) in streptozotocin (STZ)-induced diabetic mice. The diabetic mice were randomly divided into four groups (8 mice per group): diabetic control group, low-dose Gl-PS treated group (50 mg/kg, Gl-PS), high-dose Gl-PS treated group (150 mg/kg, Gl-PS) and positive drug control treated group (glibenclamide, 4 mg/kg), with normal mice used as the control group. Body weights, fasting blood glucose (FBG), serum insulin and blood lipid levels of mice were measured. After 28 days of treatment with Gl-PS, body weights and serum insulin levels of the Gl-PS treated groups was significantly higher than that of the diabetic control group, whereas FBG levels was significantly lower. Moreover, total cholesterol (TC), triglyceride (TG) and low density lipoprotein cholesterol (LDL-C) levels of the Gl-PS treated groups had dropped, whereas the high density lipoprotein cholesterol (HDL-C) levels had increased. In addition, according to acute toxicity studies, Gl-PS did not cause behavioral changes and any death of mice. These data suggest that Gl-PS has an antihyperglycemic effect. Furthermore, considering the Gl-PS effects on lipid profile, it may be a potential hypolipidaemic agent, which will be a great advantage in treating diabetic conditions associated with atherosclerosis or hyperlipidemia. PMID:22016649

  9. Tubular overexpression of Gremlin in transgenic mice aggravates renal damage in diabetic nephropathy.

    PubMed

    Marchant, Vanessa; Droguett, Alejandra; Valderrama, Graciela; Burgos, M Eugenia; Carpio, Daniel; Kerr, Bredford; Ruiz-Ortega, Marta; Egido, Jesús; Mezzano, Sergio

    2015-09-15

    Diabetic nephropathy (DN) is currently a leading cause of end-stage renal failure worldwide. Gremlin was identified as a gene differentially expressed in mesangial cells exposed to high glucose and in experimental diabetic kidneys. We have described that Gremlin is highly expressed in biopsies from patients with diabetic nephropathy, predominantly in areas of tubulointerstitial fibrosis. In streptozotocin (STZ)-induced experimental diabetes, Gremlin deletion using Grem1 heterozygous knockout mice or by gene silencing, ameliorates renal damage. To study the in vivo role of Gremlin in renal damage, we developed a diabetic model induced by STZ in transgenic (TG) mice expressing human Gremlin in proximal tubular epithelial cells. The albuminuria/creatinuria ratio, determined at week 20 after treatment, was significantly increased in diabetic mice but with no significant differences between transgenic (TG/STZ) and wild-type mice (WT/STZ). To assess the level of renal damage, kidney tissue was analyzed by light microscopy (periodic acid-Schiff and Masson staining), electron microscopy, and quantitative PCR. TG/STZ mice had significantly greater thickening of the glomerular basement membrane, increased mesangial matrix, and podocytopenia vs. WT/STZ. At the tubulointerstitial level, TG/STZ showed increased cell infiltration and mild interstitial fibrosis. In addition, we observed a decreased expression of podocin and overexpression of monocyte chemoattractant protein-1 and fibrotic-related markers, including transforming growth factor-?1, Col1a1, and ?-smooth muscle actin. Together, these results show that TG mice overexpressing Gremlin in renal tubules develop greater glomerular and tubulointerstitial injury in response to diabetic-mediated damage and support the involvement of Gremlin in diabetic nephropathy. PMID:26155842

  10. Gut microbial markers are associated with diabetes onset, regulatory imbalance, and IFN-? level in NOD mice.

    PubMed

    Krych, ?; Nielsen, D S; Hansen, A K; Hansen, C H F

    2015-01-01

    Gut microbiota regulated imbalances in the host's immune profile seem to be an important factor in the etiology of type 1 diabetes (T1D), and identifying bacterial markers for T1D may therefore be useful in diagnosis and prevention of T1D. The aim of the present study was to investigate the link between the early gut microbiota and immune parameters of non-obese diabetic (NOD) mice in order to select alleged bacterial markers of T1D. Gut microbial composition in feces was analyzed with 454/FLX Titanium (Roche) pyro-sequencing and correlated with diabetes onset age and immune cell populations measured in diabetic and non-diabetic mice at 30 weeks of age. The early gut microbiota composition was found to be different between NOD mice that later in life were classified as diabetic or non-diabetic. Those differences were further associated with changes in FoxP3(+) regulatory T cells, CD11b(+) dendritic cells, and IFN-? production. The model proposed in this work suggests that operational taxonomic units classified to S24-7, Prevotella, and an unknown Bacteriodales (all Bacteroidetes) act in favor of diabetes protection whereas members of Lachnospiraceae, Ruminococcus, and Oscillospira (all Firmicutes) promote pathogenesis. PMID:25648687

  11. ?-Lipoic Acid Protects Diabetic Apolipoprotien E-deficient Mice from Nephropathy

    PubMed Central

    Yi, Xianwen; Nickeleit, Volker; James, Leighton R; Maeda, Nobuyo

    2010-01-01

    Aim Both hyperglycemia and hyperlipidemia increase oxidative stress, and contribute to the development of diabetic nephropathy (DN). We investigated effects of ?-lipoic acid, a natural antioxidant and a cofactor in the multienzyme complexes, on the development of DN in diabetic apolipoprotein E-deficient mice. Methods Twelve-weeks-old male apoE?/? mice on C57BL/6J genetic background were made diabetic with injections of streptozotocin (STZ). STZ-treated diabetic apoE?/? mice and non-diabetic control were fed with a synthetic high fat (HF) diet with or without LA supplementation. Multiple parameters including plasma glucose, cholesterol, oxidative stress markers, cytokines, and kidney cortex gene expression, and glomerular morphology were evaluated. Results LA supplementation markedly protected the beta cells and reduced cholesterol levels, attenuated albuminuria and glomerular mesangial expansion in the diabetic mice. Reno-protection by LA was equally effective regardless of whether the dietary supplementation was started 4 weeks before, simultaneously with, or 4 weeks after the induction of diabetes by STZ. LA supplementation significantly improved DN and oxidative stress in the diabetic mice. Severity of albuminuria was positively correlated with level of thiobarbituric acid reactive substances (TBARs) in the kidney (r2=0.62, P<0.05). Diabetes significantly changed the kidney expression of Rage, Sod2, Tgfb1 and Ctgf, Pdp2, nephrin and Lias. LA supplementation corrected these changes except that it further suppressed the expression of the Lias gene coding for lipoic acid synthase. Conclusions Our data indicate that LA supplementation effectively attenuates the development and progression of DN through its antioxidant effect as well as enhancing glucose oxidation. PMID:20801062

  12. Dosing time-dependent changes in the analgesic effect of pregabalin on diabetic neuropathy in mice.

    PubMed

    Akamine, Takahiro; Koyanagi, Satoru; Kusunose, Naoki; Hashimoto, Hana; Taniguchi, Marie; Matsunaga, Naoya; Ohdo, Shigehiro

    2015-07-01

    Patients with diabetes often develop peripheral nerve complications, including numbness and pain in the extremities. Diabetes-induced peripheral neuropathic pain is characterized by hypersensitivity to innocuous stimuli, known as tactile allodynia. Pregabalin (PGN) is currently used to treat diabetes-induced peripheral neuropathy and alleviates allodynia. In the present study, we demonstrated that the antiallodynic effect of PGN on diabetic mice was modulated by circadian changes in its intestinal absorption. A single intraperitoneal administration of 200 mg/kg streptozotocin (STZ) to mice induced type I diabetic pathologic changes that were accompanied by tactile allodynia. The intensity of tactile allodynia in STZ-induced diabetic mice was alleviated by the oral administration of PGN; however, the antiallodynic effect varied according to its dosing time. The analgesic effect of PGN was enhanced by its administration at the times of day when its intestinal absorption was accelerated. Organic cation transporter novel type 1 (Octn1) mediated the uptake of PGN into intestinal epithelial cells. The expression of Octn1 in the small intestine of STZ-induced diabetic mice oscillated in a circadian time-dependent manner. This oscillation in Octn1 appeared to cause the time of day-dependent changes in the intestinal absorption of PGN. Similar dosing time dependencies of the antiallodynic effect of PGN and oscillation in Octn1 expression were also detected in type II diabetic db/db mice. These results suggested that the dosing time-dependent differences in the analgesic effect of PGN were attributable to circadian oscillations in the intestinal expression of Octn1 and also that optimizing its dosing schedule may assist in achieving rational pharmacotherapy for diabetes-induced peripheral neuropathic pain. PMID:25962390

  13. Anti-diabetic effects of rice hull smoke extract on glucose-regulating mechanism in type 2 diabetic mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of this study is to determine the protective effect of a liquid rice hull smoke extract (RHSE) against type 2 diabetes induced by a high fat diet administered to mice. Dietary administration of 0.5% or 1% RHSE for 7 weeks results in significantly reduced blood glucose and triglyceride and to...

  14. A Humoral Immune Defect Distinguishes the Response to Staphylococcus aureus Infections in Mice with Obesity and Type 2 Diabetes from That in Mice with Type 1 Diabetes

    PubMed Central

    Farnsworth, Christopher W.; Shehatou, Cindy T.; Maynard, Robert; Nishitani, Kohei; Zuscik, Michael J.; Schwarz, Edward M.; Daiss, John L.

    2015-01-01

    Obesity and diabetes are among the greatest risk factors for infection following total joint arthroplasty. However, the underlying mechanism of susceptibility is unclear. We compared orthopedic implant-associated Staphylococcus aureus infections in type 1 (T1D) versus type 2 (T2D) diabetic mouse models and in patients with S. aureus infections, focusing on the adaptive immune response. Mice were fed a high-fat diet to initiate obesity and T2D. T1D was initiated with streptozotocin. Mice were then given a trans-tibial implant that was precoated with bioluminescent Xen36 S. aureus. Although both mouse models of diabetes demonstrated worse infection severity than controls, infection in T2D mice was more severe, as indicated by increases in bioluminescence, S. aureus CFU in tissue, and death within the first 7 days. Furthermore, T2D mice had an impaired humoral immune response at day 14 with reduced total IgG, decreased S. aureus-specific IgG, and increased IgM. These changes were not present in T1D mice. Similarly, T2D patients and obese nondiabetics with active S. aureus infections had a blunted IgG response to S. aureus. In conclusion, we report the first evidence of a humoral immune deficit, possibly due to an immunoglobulin class switch defect, in obesity and T2D during exacerbated S. aureus infection which may contribute to the increased infection risk following arthroplasty in patients with T2D and obesity. PMID:25802056

  15. Sargassum coreanum extract alleviates hyperglycemia and improves insulin resistance in db/db diabetic mice

    PubMed Central

    Park, Mi Hwa; Nam, Young Hwa

    2015-01-01

    BACKGROUND/OBJECTIVES The goal of this study was to examine the effect of Sargassum coreanum extract (SCE) on blood glucose concentration and insulin resistance in C57BL-KsJ-db/db mice. MATERIALS/METHODS For 6 weeks, male C57BL/KsJ-db/db mice were administrated SCE (0.5%, w/w), and rosiglitazone (0.005%, w/w). RESULTS A supplement of the SCE for 6 weeks induced a significant reduction in blood glucose and glycosylated hemoglobin concentrations, and it improved hyperinsulinemia compared to the diabetic control db/db mice. The glucokinase activity in the hepatic glucose metabolism increased in the SCE-supplemented db/db mice, while phosphoenolpyruvate carboxykinase and glucose-6-phosphatase activities in the SCE-supplemented db/db mice were significantly lower than those in the diabetic control db/db mice. The homeostatic index of insulin resistance was lower in the SCE-supplemented db/db mice than in the diabetic control db/db mice. CONCLUSIONS These results suggest that a supplement of the SCE lowers the blood glucose concentration by altering the hepatic glucose metabolic enzyme activities and improves insulin resistance. PMID:26425276

  16. Pregnancy Represses Induction of Efflux Transporters in Livers of Type I Diabetic Mice

    PubMed Central

    Aleksunes, Lauren M.; Xu, Jialin; Lin, Eugenia; Wen, Xia; Goedken, Michael J.; Slitt, Angela L.

    2013-01-01

    Purpose The purpose of this study was to determine whether down-regulation of transcription factor signaling during pregnancy disrupts the induction of efflux transporters in type I diabetic mice. Methods Type I diabetes was induced in female C57BL/6 mice with multiple low dose intraperitoneal injections of streptozotocin (STZ) at least 2 weeks prior to mating with normoglycemic male mice. On gestation day 14, livers were collected from vehicle- and STZ-treated non-pregnant and pregnant mice for quantification of efflux transporter and transcription factor signaling. Results STZ treatment up-regulated expression of Mrp1–5, Mdr1, Abcg5, Abcg8, Bcrp, and Bsep mRNA and/or protein in the livers of non-pregnant mice. Interestingly, little to no change in transporter expression was observed in STZ-treated mice that became pregnant. Enhanced PPAR?, Nrf2, and FXR transcription factor signaling, as quantified by nuclear binding and target gene regulation, was also observed in non-pregnant mice treated with STZ. Similar to efflux transporter expression, activation of these transcriptional pathways was diminished by pregnancy in STZ-treated mice. Conclusions This study demonstrates the opposing regulation of hepatobiliary efflux transporters in response to diabetes and pregnancy and points to PPAR?, Nrf2, and FXR as candidate pathways underlying the differential expression of transporters. PMID:23319174

  17. Ecklonia cava Inhibits Glucose Absorption and Stimulates Insulin Secretion in Streptozotocin-Induced Diabetic Mice

    PubMed Central

    Kim, Hye Kyung

    2012-01-01

    Aims of study. Present study investigated the effect of Ecklonia cava (EC) on intestinal glucose uptake and insulin secretion. Materials and methods. Intestinal Na+-dependent glucose uptake (SGU) and Na+-dependent glucose transporter 1 (SGLT1) protein expression was determined using brush border membrane vesicles (BBMVs). Glucose-induced insulin secretion was examined in pancreatic ?-islet cells. The antihyperglycemic effects of EC, SGU, and SGLT1 expression were determined in streptozotocin (STZ)-induced diabetic mice. Results. Methanol extract of EC markedly inhibited intestinal SGU of BBMV with the IC50 value of 345??g/mL. SGLT1 protein expression was dose dependently down regulated with EC treatment. Furthermore, insulinotrophic effect of EC extract was observed at high glucose media in isolated pancreatic ?-islet cells in vitro. We next conducted the antihyperglycemic effect of EC in STZ-diabetic mice. EC supplementation markedly suppressed SGU and SGLT1 abundance in BBMV from STZ mice. Furthermore, plasma insulin level was increased by EC treatment in diabetic mice. As a result, EC supplementation improved postprandial glucose regulation, assessed by oral glucose tolerance test, in diabetic mice. Conclusion. These results suggest that EC play a role in controlling dietary glucose absorption at the intestine and insulinotrophic action at the pancreas contributing blood glucose homeostasis in diabetic condition. PMID:22645628

  18. Ecklonia cava Inhibits Glucose Absorption and Stimulates Insulin Secretion in Streptozotocin-Induced Diabetic Mice.

    PubMed

    Kim, Hye Kyung

    2012-01-01

    Aims of study. Present study investigated the effect of Ecklonia cava (EC) on intestinal glucose uptake and insulin secretion. Materials and methods. Intestinal Na(+)-dependent glucose uptake (SGU) and Na(+)-dependent glucose transporter 1 (SGLT1) protein expression was determined using brush border membrane vesicles (BBMVs). Glucose-induced insulin secretion was examined in pancreatic ?-islet cells. The antihyperglycemic effects of EC, SGU, and SGLT1 expression were determined in streptozotocin (STZ)-induced diabetic mice. Results. Methanol extract of EC markedly inhibited intestinal SGU of BBMV with the IC(50) value of 345??g/mL. SGLT1 protein expression was dose dependently down regulated with EC treatment. Furthermore, insulinotrophic effect of EC extract was observed at high glucose media in isolated pancreatic ?-islet cells in vitro. We next conducted the antihyperglycemic effect of EC in STZ-diabetic mice. EC supplementation markedly suppressed SGU and SGLT1 abundance in BBMV from STZ mice. Furthermore, plasma insulin level was increased by EC treatment in diabetic mice. As a result, EC supplementation improved postprandial glucose regulation, assessed by oral glucose tolerance test, in diabetic mice. Conclusion. These results suggest that EC play a role in controlling dietary glucose absorption at the intestine and insulinotrophic action at the pancreas contributing blood glucose homeostasis in diabetic condition. PMID:22645628

  19. TAK1 inhibition prevents the development of autoimmune diabetes in NOD mice

    PubMed Central

    Cao, Hui; Lu, Jingli; Du, Jiao; Xia, Fei; Wei, Shouguo; Liu, Xiulan; Liu, Tingting; Liu, Yang; Xiang, Ming

    2015-01-01

    Transforming growth factor-? activated kinase-1 (TAK1, Map3k7), a member of the mitogen-activated protein kinase kinase kinase (MAP3K) family, is essential in innate and adaptive immune responses. We postulated that blockade of TAK1 would affect autoimmune diabetes in non-obese diabetic (NOD) mice. Administration of 5Z-7-oxozeaenol (OZ), a TAK1 inhibitor, decreased the incidence and delayed the onset of autoimmune diabetes in both spontaneous and accelerated (cyclophosphamide-induced) experimental NOD mice. OZ also reduced insulitis, preserved islet function, increased the expression of ?1- antitrypsin (AAT), and severely inhibited NF-?B and JNK/AP-1 signaling pathways in immune organs and pancreatic tissues. Importantly, TAK1 inhibition by OZ elicited a Th1 to Th2 cytokine shift, and increased TGF-?1 production in cultured T lymphocytes supernatants. Systemic TAK1 inhibition induced immature DCs with lower expressions of MHC-II and CD86, attenuated DC-mediated T cell proliferation in allogeneic MLR, and production of cytokine IL-12p70 in DCs suspensions. The results indicate that TAK1 inhibition with OZ was associated with a lower frequency of autoimmune diabetes in NOD mice. The net effect of TAK1 inhibition in NOD mice therefore appears to be protective rather than disease-enhancing. Strategies targeting TAK1 specifically in NOD mice might prove useful for the treatment of autoimmune diabetes in general. PMID:26459028

  20. Gene therapy with neurogenin3, betacellulin and SOCS1 reverses diabetes in NOD mice.

    PubMed

    Li, R; Buras, E; Lee, J; Liu, R; Liu, V; Espiritu, C; Ozer, K; Thompson, B; Nally, L; Yuan, G; Oka, K; Chang, B; Samson, S; Yechoor, V; Chan, L

    2015-11-01

    Islet transplantation for type 1 diabetes is limited by a shortage of donor islets and requirement for immunosuppression. We approached this problem by inducing in vivo islet neogenesis in non-obese diabetic (NOD) diabetic mice, a model of autoimmune diabetes. We demonstrate that gene therapy with helper-dependent adenovirus carrying neurogenin3 (Ngn3), an islet lineage-defining transcription factor, and betacellulin (Btc), an islet growth factor, leads to the induction of periportal insulin-positive cell clusters in the liver, which are rapidly destroyed. To specifically accord protection to these 'neo-islets' from cytokine-mediated destruction, we overexpressed suppressor of cytokine signaling 1 (SOCS1) gene, using a rat insulin promoter in combination with Ngn3 and Btc. With this approach, about half of diabetic mice attained euglycemia sustained for over 4 months, regain glucose tolerance and appropriate glucose-stimulated insulin secretion. Histological analysis revealed periportal islet hormone-expressing 'neo-islets' in treated mouse livers. Despite evidence of persistent 'insulitis' with activated T cells, these 'neo-islets' persist to maintain euglycemia. This therapy does not affect diabetogenicity of splenocytes, as they retain the ability to transfer diabetes. This study thus provides a proof-of-concept for engineering in vivo islet neogenesis with targeted resistance to cytokine-mediated destruction to provide a long-term reversal of diabetes in NOD mice. PMID:26172077

  1. Remodeling of cardiac cholinergic innervation and control of heart rate in mice with streptozotocin-induced diabetes.

    PubMed

    Mabe, Abigail M; Hoover, Donald B

    2011-07-01

    Cardiac autonomic neuropathy is a frequent complication of diabetes and often presents as impaired cholinergic regulation of heart rate. Some have assumed that diabetics have degeneration of cardiac cholinergic nerves, but basic knowledge on this topic is lacking. Accordingly, our goal was to evaluate the structure and function of cardiac cholinergic neurons and nerves in C57BL/6 mice with streptozotocin-induced diabetes. Electrocardiograms were obtained weekly from conscious control and diabetic mice for 16 weeks. Resting heart rate decreased in diabetic mice, but intrinsic heart rate was unchanged. Power spectral analysis of electrocardiograms revealed decreased high frequency and increased low frequency power in diabetic mice, suggesting a relative reduction of parasympathetic tone. Negative chronotropic responses to right vagal nerve stimulation were blunted in 16-week diabetic mice, but postjunctional sensitivity of isolated atria to muscarinic agonists was unchanged. Immunohistochemical analysis of hearts from diabetic and control mice showed no difference in abundance of cholinergic neurons, but cholinergic nerve density was increased at the sinoatrial node of diabetic mice (16 weeks: 14.9±1.2% area for diabetics versus 8.9±0.8% area for control, P<0.01). We conclude that disruption of cholinergic function in diabetic mice cannot be attributed to a loss of cardiac cholinergic neurons and nerve fibers or altered cholinergic sensitivity of the atria. Instead, decreased responses to vagal stimulation might be caused by a defect of preganglionic cholinergic neurons and/or ganglionic neurotransmission. The increased density of cholinergic nerves observed at the sinoatrial node of diabetic mice might be a compensatory response. PMID:21334985

  2. Polyopes lancifolia Extract, a Potent ?-Glucosidase Inhibitor, Alleviates Postprandial Hyperglycemia in Diabetic Mice

    PubMed Central

    Min, Seong Won; Han, Ji Sook

    2014-01-01

    This study was designed to investigate the inhibitory effects of Polyopes lancifolia extract (PLE) on ?-glucosidase activity, ?-amylase activitiy, and postprandial hyperglycemia in streptozotocin (STZ)-induced diabetic mice. The results of this study revealed a marked inhibitory effect of PLE on ?-glucosidase and ?-amylase activities. The IC50s of PLE against ?-glucosidase and ?-amylase were 0.20 mg/mL and 0.35 mg/mL, respectively. PLE was a more effective inhibitor of ?-glucosidase and ?-amylase activities than acarbose, the positive control. The postprandial blood glucose levels of STZ-induced diabetic mice were significantly lower in the PLE treated group than in the control group. Moreover, PLE administration was associated with a decreased area under the curve for the glucose response in diabetic mice. These results indicate that PLE may be a potent inhibitor of ?-glucosidase and ?-amylase activities and may suppress postprandial hyperglycemia. PMID:24772403

  3. Phlorofucofuroeckol A isolated from Ecklonia cava alleviates postprandial hyperglycemia in diabetic mice.

    PubMed

    You, Han-Nui; Lee, Hyun-Ah; Park, Mi-Hwa; Lee, Ji-Hyeok; Han, Ji-Sook

    2015-04-01

    This study was designed to investigate whether phlorofucofuroeckol A inhibited ?-glucosidase and ?-amylase activities and alleviated postprandial hyperglycemia in diabetic mice. Phlorofucofuroeckol A that was isolated from Ecklonia cava (brown algae) demonstrated prominent inhibitory effects against ?-glucosidase and ?-amylase activities. The IC50 values of phlorofucofuroeckol A against ?-glucosidase and ?-amylase were 19.52 and 6.34?M, respectively. These inhibitory activities of phlorofucofuroeckol A were higher than those of acarbose, which was used as a positive control. Increases in postprandial blood glucose levels were significantly more suppressed in the group administered phlorofucofuroeckol A compared to the control group in both diabetic and normal mice. Moreover, the area under the curve was significantly lower after phlorofucofuroeckol A administration (2296 versus 2690mmolmin/l) in the diabetic mice. These results suggested that phlorofucofuroeckol A is a potent ?-glucosidase inhibitor and can alleviate the postprandial hyperglycemia that is caused by starch. PMID:25680946

  4. Augmenting podocyte injury promotes advanced diabetic kidney disease in Akita mice

    PubMed Central

    Wang, Liming; Tang, Yuping; Eisner, William; Sparks, Matthew A.; Buckley, Anne F.; Spurney, Robert F.

    2014-01-01

    To determine if augmenting podocyte injury promotes the development of advanced diabetic nephropathy (DN), we created mice that expressed the enzyme cytosine deaminase (CD) specifically in podocytes of diabetic Akita mice (Akita-CD mice). In these mice, treatment with the prodrug 5-flucytosine (5-FC) causes podocyte injury as a result of conversion to the toxic metabolite 5-fluorouracil (5-FU). We found that treatment of 4-5 week old Akita mice with 5-FC for 5 days caused robust albuminuria at 16 and 20 weeks of age compared to 5-FC treated Akita controls, which do not express CD (Akita CTLs). By 20 weeks of age, there was a significant increase in mesangial expansion in Akita-CD mice compared to Akita CTLs, which was associated with a variable increase in glomerular basement membrane (GBM) width and interstitial fibrosis. At 20 weeks of age, podocyte number was similarly reduced in both groups of Akita mice, and was inversely correlated with the albuminuria and mesangial expansion. Thus, enhancing podocyte injury early in the disease process promotes the development of prominent mesangial expansion, interstitial fibrosis, increased GBM thickness and robust albuminuria. These data suggest that podocytes play a key role in the development of advanced features of diabetic kidney disease. PMID:24491571

  5. Administration of Danhong Injection to diabetic db/db mice inhibits the development of diabetic retinopathy and nephropathy

    PubMed Central

    Liu, Mengyang; Pan, Quan; Chen, Yuanli; Yang, Xiaoxiao; Zhao, Buchang; Jia, Lifu; Zhu, Yan; Zhang, Boli; Gao, Xiumei; Li, Xiaoju; Han, Jihong; Duan, Yajun

    2015-01-01

    Danhong Injection (DHI), a Chinese medicine for treatment of patients with coronary heart disease, inhibits primary abdominal aortic aneurysms in apoE deficient (apoE?/?) mice. Formation of microaneurysms plays an important role in the development of diabetic retinopathy and nephropathy. It remains unknown if DHI can reduce these diabetic complications. In this study, diabetic db/db mice in two groups were injected with saline and DHI, respectively, for 14 weeks. Blood and tissue samples were collected to determine serum glucose, lipids and tissue structure. DHI reduced diabetes-induced body weight gain, serum cholesterol and glucose levels. In retinas, DHI blocked the shrink of whole retina and retinal sub-layers by inhibiting expression of caspase 3, matrix metalloproteinase 2 (MMP-2) and MMP-9, accumulation of carbohydrate macromolecules and formation of acellular capillaries. DHI improved renal functions by inhibiting mesangial matrix expansion, expression of vascular endothelial growth factor A, fibronectin and advanced glycation end products in kidneys. Mechanistically, DHI induced expression of glucokinase, AMPK?/phosphorylated AMPK?, insulin receptor substrate 1, fibroblast growth factor 21 and peroxisome proliferator-activated ?. Expression of genes responsible for energy expenditure was also activated by DHI. Therefore, DHI inhibits diabetic retinopathy and nephropathy by ameliorating glucose metabolism and demonstrates a potential application in clinics. PMID:26061387

  6. Administration of Danhong Injection to diabetic db/db mice inhibits the development of diabetic retinopathy and nephropathy.

    PubMed

    Liu, Mengyang; Pan, Quan; Chen, Yuanli; Yang, Xiaoxiao; Zhao, Buchang; Jia, Lifu; Zhu, Yan; Zhang, Boli; Gao, Xiumei; Li, Xiaoju; Han, Jihong; Duan, Yajun

    2015-01-01

    Danhong Injection (DHI), a Chinese medicine for treatment of patients with coronary heart disease, inhibits primary abdominal aortic aneurysms in apoE deficient (apoE(-/-)) mice. Formation of microaneurysms plays an important role in the development of diabetic retinopathy and nephropathy. It remains unknown if DHI can reduce these diabetic complications. In this study, diabetic db/db mice in two groups were injected with saline and DHI, respectively, for 14 weeks. Blood and tissue samples were collected to determine serum glucose, lipids and tissue structure. DHI reduced diabetes-induced body weight gain, serum cholesterol and glucose levels. In retinas, DHI blocked the shrink of whole retina and retinal sub-layers by inhibiting expression of caspase 3, matrix metalloproteinase 2 (MMP-2) and MMP-9, accumulation of carbohydrate macromolecules and formation of acellular capillaries. DHI improved renal functions by inhibiting mesangial matrix expansion, expression of vascular endothelial growth factor A, fibronectin and advanced glycation end products in kidneys. Mechanistically, DHI induced expression of glucokinase, AMPK?/phosphorylated AMPK?, insulin receptor substrate 1, fibroblast growth factor 21 and peroxisome proliferator-activated ?. Expression of genes responsible for energy expenditure was also activated by DHI. Therefore, DHI inhibits diabetic retinopathy and nephropathy by ameliorating glucose metabolism and demonstrates a potential application in clinics. PMID:26061387

  7. Antibody combination therapy targeting CD25, CD70 and CD8 reduces islet inflammation and improves glycaemia in diabetic mice

    PubMed Central

    Alkhamis, T; Barbic, J; Crnogorac-Jurcevic, T; Greenlaw, R E; Peakman, M; Jurcevic, S

    2012-01-01

    Destruction of pancreatic islets in type 1 diabetes is caused by infiltrating, primed and activated T cells. In a clinical setting this autoimmune process is already in an advanced stage before intervention therapy can be administered. Therefore, an effective intervention needs to reduce islet inflammation and preserve any remaining islet function. In this study we have investigated the role of targeting activated T cells in reversing autoimmune diabetes. A combination therapy consisting of CD25-, CD70- and CD8-specific monoclonal antibodies was administered to non-obese diabetic (NOD) mice with either new-onset diabetes or with advanced diabetes. In NOD mice with new-onset diabetes antibody combination treatment reversed hyperglycaemia and achieved long-term protection from diabetes (blood glucose <13·9 mmol/l) in >50% of mice. In contrast, in the control, untreated group blood glucose levels continued to increase and none of the mice were protected from diabetes (P < 0·0001). Starting therapy early when hyperglycaemia was relatively mild proved critical, as the mice with advanced diabetes showed less efficient control of blood glucose and shorter life span. Histological analysis (insulitis score) showed islet preservation and reduced immune infiltration in all treated groups, compared to their controls. In conclusion, antibody combination therapy that targets CD25, CD70 and CD8 results in decreased islet infiltration and improved blood glucose levels in NOD mice with established diabetes. PMID:23039884

  8. The protective effects of oral low-dose quercetin on diabetic nephropathy in hypercholesterolemic mice

    PubMed Central

    Gomes, Isabele B. S.; Porto, Marcella L.; Santos, Maria C. L. F. S.; Campagnaro, Bianca P.; Gava, Agata L.; Meyrelles, Silvana S.; Pereira, Thiago M. C.; Vasquez, Elisardo C.

    2015-01-01

    Aims: Diabetic nephropathy (DN) is one of the most important causes of chronic renal disease, and the incidence of DN is increasing worldwide. Considering our previous report (Gomes et al., 2014) indicating that chronic treatment with oral low-dose quercetin (10 mg/Kg) demonstrated anti-oxidative, anti-apoptotic and renoprotective effects in the C57BL/6J model of DN, we investigated whether this flavonoid could also have beneficial effects in concurrent DN and spontaneous atherosclerosis using the apolipoprotein E-deficient mouse (apoE?/?). Methods: Streptozotocin was used to induce diabetes (100 mg/kg/day, 3 days) in male apoE?/? mice (8 week-old). After 6 weeks, the mice were randomly separated into DQ: diabetic apoE?/? mice treated with quercetin (10 mg/kg/day, 4 weeks, n = 8), DV: diabetic ApoE?/? mice treated with vehicle (n = 8) and ND: non-treated non-diabetic mice (n = 8). Results: Quercetin treatment diminished polyuria (~30%; p < 0.05), glycemia (~25%, p < 0.05), normalized the hypertriglyceridemia. Moreover, this bioflavonoid diminished creatininemia (~30%, p < 0.01) and reduced proteinuria but not to normal levels. We also observed protective effects on the renal structural changes, including normalization of the index of glomerulosclerosis and kidney weight/body weight. Conclusions: Our data revealed that quercetin treatment significantly reduced DN in hypercholesterolemic mice by inducing biochemical changes (decrease in glucose and triglycerides serum levels) and reduction of glomerulosclerosis. Thus, this study highlights the relevance of quercetin as an alternative therapeutic option for DN, including in diabetes associated with dyslipidemia. PMID:26388784

  9. Type 2 Diabetic Rats on Diet Supplemented With Chromium Malate Show Improved Glycometabolism, Glycometabolism-Related Enzyme Levels and Lipid Metabolism

    PubMed Central

    Feng, Weiwei; Zhao, Ting; Mao, Guanghua; Wang, Wei; Feng, Yun; Li, Fang; Zheng, Daheng; Wu, Huiyu; Jin, Dun; Yang, Liuqing; Wu, Xiangyang

    2015-01-01

    Our previous study showed that chromium malate improved the regulation of blood glucose in mice with alloxan-induced diabetes. The present study was designed to evaluate the effect of chromium malate on glycometabolism, glycometabolism-related enzymes and lipid metabolism in type 2 diabetic rats. Our results showed that fasting blood glucose, serum insulin level, insulin resistance index and C-peptide level in the high dose group had a significant downward trend when compared with the model group, chromium picolinate group and chromium trichloride group. The hepatic glycogen, glucose-6-phosphate dehydrogenase, glucokinase, Glut4, phosphor-AMPK?1 and Akt levels in the high dose group were significantly higher than those of the model, chromium picolinate and chromium trichloride groups. Chromium malate in a high dose group can significantly increase high density lipoprotein cholesterol level while decreasing the total cholesterol, low density lipoprotein cholesterol and triglyceride levels when compared with chromium picolinate and chromium trichloride. The serum chromium content in chromium malate and chromium picolinate group is significantly higher than that of the chromium trichloride group. The results indicated that the curative effects of chromium malate on glycometabolism, glycometabolism-related enzymes and lipid metabolism changes are better than those of chromium picolinate and chromium trichloride. Chromium malate contributes to glucose uptake and transport in order to improved glycometabolism and glycometabolism-related enzymes. PMID:25942313

  10. Low TGF?1 expression prevents and high expression exacerbates diabetic nephropathy in mice.

    PubMed

    Hathaway, Catherine K; Gasim, Adil M H; Grant, Ruriko; Chang, Albert S; Kim, Hyung-Suk; Madden, Victoria J; Bagnell, C Robert; Jennette, J Charles; Smithies, Oliver; Kakoki, Masao

    2015-05-01

    Nephropathy develops in many but not all patients with long-standing type 1 diabetes. Substantial efforts to identify genotypic differences explaining this differential susceptibility have been made, with limited success. Here, we show that the expression of the transforming growth factor ?1 gene (Tgfb1) affects the development of diabetic nephropathy in mice. To do this we genetically varied Tgfb1 expression in five steps, 10%, 60%, 100%, 150%, and 300% of normal, in mice with type 1 diabetes caused by the Akita mutation in the insulin gene (Ins2(Akita)). Although plasma glucose levels were not affected by Tgfb1 genotype, many features of diabetic nephropathy (mesangial expansion, elevated plasma creatinine and urea, decreased creatinine clearance and albuminuria) were progressively ameliorated as Tgfb1 expression decreased and were progressively exacerbated when expression was increased. The diabetic 10% hypomorphs had comparable creatinine clearance and albumin excretion to wild-type mice and no harmful changes in renal morphology. The diabetic 300% hypermorphs had ?1/3 the creatinine clearance of wild-type mice, >20× their albumin excretion, ?3× thicker glomerular basement membranes and severe podocyte effacement, matching human diabetic nephropathy. Switching Tgfb1 expression from low to high in the tubules of the hypomorphs increased their albumin excretion more than 10-fold but creatinine clearance remained high. Switching Tgfb1 expression from low to high in the podocytes markedly decreased creatinine clearance, but minimally increased albumin excretion. Decreasing expression of Tgfb1 could be a promising option for preventing loss of renal function in diabetes. PMID:25902541

  11. Low TGF?1 expression prevents and high expression exacerbates diabetic nephropathy in mice

    PubMed Central

    Hathaway, Catherine K.; Gasim, Adil M. H.; Grant, Ruriko; Chang, Albert S.; Kim, Hyung-Suk; Madden, Victoria J.; Bagnell, C. Robert; Jennette, J. Charles; Smithies, Oliver; Kakoki, Masao

    2015-01-01

    Nephropathy develops in many but not all patients with long-standing type 1 diabetes. Substantial efforts to identify genotypic differences explaining this differential susceptibility have been made, with limited success. Here, we show that the expression of the transforming growth factor ?1 gene (Tgfb1) affects the development of diabetic nephropathy in mice. To do this we genetically varied Tgfb1 expression in five steps, 10%, 60%, 100%, 150%, and 300% of normal, in mice with type 1 diabetes caused by the Akita mutation in the insulin gene (Ins2Akita). Although plasma glucose levels were not affected by Tgfb1 genotype, many features of diabetic nephropathy (mesangial expansion, elevated plasma creatinine and urea, decreased creatinine clearance and albuminuria) were progressively ameliorated as Tgfb1 expression decreased and were progressively exacerbated when expression was increased. The diabetic 10% hypomorphs had comparable creatinine clearance and albumin excretion to wild-type mice and no harmful changes in renal morphology. The diabetic 300% hypermorphs had ?1/3 the creatinine clearance of wild-type mice, >20× their albumin excretion, ?3× thicker glomerular basement membranes and severe podocyte effacement, matching human diabetic nephropathy. Switching Tgfb1 expression from low to high in the tubules of the hypomorphs increased their albumin excretion more than 10-fold but creatinine clearance remained high. Switching Tgfb1 expression from low to high in the podocytes markedly decreased creatinine clearance, but minimally increased albumin excretion. Decreasing expression of Tgfb1 could be a promising option for preventing loss of renal function in diabetes. PMID:25902541

  12. Severely Impaired Insulin Signaling in Chronic Wounds of Diabetic ob/ob Mice

    PubMed Central

    Goren, Itamar; Müller, Elke; Pfeilschifter, Josef; Frank, Stefan

    2006-01-01

    Wound-healing disorders are major complications of diabetes mellitus. Here, we investigated insulin-mediated signaling in nonwounded skin and in cutaneous tissue regeneration of healthy C57BL/6 and diabetes-impaired leptin-deficient obese/obese (ob/ob) mice. The insulin receptor (InsR) was abundantly expressed in wound margins and granulation tissue during acute healing in healthy mice. Remarkably, active signaling from the InsR, as assessed by phosphorylation of downstream targets such as protein tyrosine phosphatase-1B, glycogen synthase (GS), and GS kinase, was nearly absent in nonwounded and acutely healing skin from ob/ob mice. Systemic leptin administration to ob/ob mice reverted the diabetic phenotype and improved tissue regeneration as well as the impaired expression of InsR, insulin receptor substrate-1 and insulin receptor substrate-2, and downstream signaling (phosphorylation of GS kinase and GS) in late wounds and nonwounded skin of ob/ob mice. Importantly, tumor necrosis factor (TNF)-? was a mediator of insulin resistance in keratinocytes in vitro and in ob/ob wound tissue in vivo. Systemic administration of a monoclonal anti-TNF-? antibody (V1q) in wounded ob/ob mice attenuated wound inflammation, improved re-epithelialization, and restored InsR expression and signaling in wound tissue of ob/ob mice. These data suggest that InsR signaling in diabetes-impaired wounds is sensitive to inflam-matory conditions and that anti-inflammatory approaches, such as anti-TNF-? strategies, improve diabetic wound healing. PMID:16507892

  13. Glucagon Receptor Blockade With a Human Antibody Normalizes Blood Glucose in Diabetic Mice and Monkeys.

    PubMed

    Okamoto, Haruka; Kim, Jinrang; Aglione, JohnPaul; Lee, Joseph; Cavino, Katie; Na, Erqian; Rafique, Ashique; Kim, Jee Hae; Harp, Joyce; Valenzuela, David M; Yancopoulos, George D; Murphy, Andrew J; Gromada, Jesper

    2015-08-01

    Antagonizing glucagon action represents an attractive therapeutic option for reducing hepatic glucose production in settings of hyperglycemia where glucagon excess plays a key pathophysiological role. We therefore generated REGN1193, a fully human monoclonal antibody that binds and inhibits glucagon receptor (GCGR) signaling in vitro. REGN1193 administration to diabetic ob/ob and diet-induced obese mice lowered blood glucose to levels observed in GCGR-deficient mice. In diet-induced obese mice, REGN1193 reduced food intake, adipose tissue mass, and body weight. REGN1193 increased circulating levels of glucagon and glucagon-like peptide 1 and was associated with reversible expansion of pancreatic ?-cell area. Hyperglucagonemia and ?-cell hyperplasia was observed in fibroblast growth factor 21-deficient mice treated with REGN1193. Single administration of REGN1193 to diabetic cynomolgus monkeys normalized fasting blood glucose and glucose tolerance and increased circulating levels of glucagon and amino acids. Finally, administration of REGN1193 for 8 weeks to normoglycemic cynomolgus monkeys did not cause hypoglycemia or increase pancreatic ?-cell area. In summary, the GCGR-blocking antibody REGN1193 normalizes blood glucose in diabetic mice and monkeys but does not produce hypoglycemia in normoglycemic monkeys. Thus, REGN1193 provides a potential therapeutic modality for diabetes mellitus and acute hyperglycemic conditions. PMID:26020795

  14. Human embryonic stem cell-derived pancreatic endoderm alleviates diabetic pathology and improves reproductive outcome in C57BL/KsJ-Lep(db/+) gestational diabetes mellitus mice.

    PubMed

    Xing, Baoheng; Wang, Lili; Li, Qin; Cao, Yalei; Dong, Xiujuan; Liang, Jun; Wu, Xiaohua

    2015-07-01

    Gestational diabetes mellitus is a condition commonly encountered during mid to late pregnancy with pathologic manifestations including hyperglycemia, hyperinsulinemia, insulin resistance, and fetal maldevelopment. The cause of gestational diabetes mellitus can be attributed to both genetic and environmental factors, hence complicating its diagnosis and treatment. Pancreatic progenitors derived from human embryonic stem cells were shown to be able to effectively treat diabetes in mice. In this study, we have developed a system of treating diabetes using human embryonic stem cell-derived pancreatic endoderm in a mouse model of gestational diabetes mellitus. Human embryonic stem cells were differentiated in vitro into pancreatic endoderm, which were then transplanted into db/+ mice suffering from gestational diabetes mellitus. The transplant greatly improved glucose metabolism and reproductive outcome of the females compared with the control groups. Our findings support the feasibility of using differentiated human embryonic stem cells for treating gestational diabetes mellitus patients. PMID:26066567

  15. NaoXinTong Inhibits the Development of Diabetic Retinopathy in db/db Mice

    PubMed Central

    Liu, Mengyang; Pan, Quan; Chen, Yuanli; Yang, Xiaoxiao; Zhao, Buchang; Jia, Lifu; Zhu, Yan; Han, Jihong; Li, Xiaoju; Duan, Yajun

    2015-01-01

    Buchang NaoXinTong capsule (NXT) is a Chinese Materia Medica standardized product extracted from 16 Chinese traditional medical herbs and widely used for treatment of patients with cerebrovascular and cardiovascular diseases in China. Formation of microaneurysms plays an important role in the development of diabetic retinopathy. In this study, we investigated if??NXT can protect diabetic mice against the development of diabetic retinopathy. The db/db mice (~6 weeks old), a diabetic animal model, were divided into two groups and fed normal chow or plus NXT for 14 weeks. During the treatment, fasting blood glucose levels were monthly determined. After treatment, retinas were collected to determine retinal thickness, accumulation of carbohydrate macromolecules, and caspase-3 (CAS-3) expression. Our results demonstrate that administration of NXT decreased fasting blood glucose levels. Associated with the decreased glucose levels, NXT blocked the diabetes-induced shrink of multiple layers, such as photoreceptor layer and outer nuclear/plexiform layers, in the retina. NXT also inhibited the diabetes-induced expression of CAS-3 protein and mRNA, MMP-2/9 and TNF? mRNA, accumulation of carbohydrate macromolecules, and formation of acellular capillaries in the retina. Taken together, our study shows that NXT can inhibit the development of diabetic retinopathy and suggests a new potential application of NXT in clinic. PMID:25821481

  16. Enhanced wind-up of the C-fiber-mediated nociceptive flexor reflex movement following painful diabetic neuropathy in mice.

    PubMed

    Kimura, Satoko; Tanabe, Mitsuo; Honda, Motoko; Ono, Hideki

    2005-02-01

    We examined wind-up of the nociceptive flexor withdrawal responses in diabetic mice that had developed tactile allodynia after treatment with streptozotocin (STZ). In control and STZ-treated mice, simultaneous activation of Adelta- and C-fibers by electrical stimuli at C-fiber intensity delivered to the ventral aspect of the toe elicited a biphasic withdrawal reflex composed of short- and long-latency movements of the ipsilateral hind paw that were respectively mediated by activation of Adelta- and C-fibers. There were no significant differences between control and diabetic mice in the activation threshold of each reflex movement or the amplitude of reflexes elicited by various stimulus intensities. However, a repetitive conditioning stimulus (CS) elicited significantly greater wind-up of the C-fiber-mediated movement and early saturation of wind-up in diabetic mice. In both control and diabetic mice, the CS elicited no or occasionally slight wind-up of the A delta-fiber-mediated movement. Moreover, post-CS facilitation, which reflects the prolonged excitability increase, was observed in both Adelta-fiber- and C-fiber-mediated movements of control mice, whereas significant post-CS facilitation was only obtained in the C-fiber-mediated movement of diabetic mice, which may reflect supraspinal descending influences. Such changes in the excitability of spinal neurons in diabetic mice may represent some aspect of painful diabetic neuropathy. PMID:15684569

  17. Caprine pancreatic islet xenotransplantation into diabetic immunosuppressed BALB/c mice

    PubMed Central

    Hani, Homayoun; Allaudin, Zeenathul N; Mohd-Lila, Mohd-Azmi; Ibrahim, Tengku A Tengku; Othman, Abas M

    2014-01-01

    Background Type 1 diabetes mellitus is a devastating disease for which there is currently no cure, but only lifetime management. Islet xenotransplantation is a promising technique for the restoration of blood glucose control in patients with diabetes mellitus. The purpose of this study was to explore the potential use of caprine (goat) islet cells as xenogeneic grafts in the treatment for diabetes in a mouse model. Methods Caprine pancreases were harvested and transported to the laboratory under conditions optimized to prevent ischemia. Islets were isolated, purified, and tested for functionality. Caprine islets (2000 islet equivalent) were transplanted beneath the kidney capsules of diabetic BALB/c mice under thalidomide-induced immunosuppression. Blood glucose and insulin levels of grafted mice were evaluated by glucometer and enzyme-linked immunosorbent assay kit, respectively. The functionality and quality of caprine pancreatic islet grafts were assessed by intraperitoneal glucose tolerance tests. Results The viability of purified islet cells exceeded 90%. Recipient mice exhibited normoglycemia (<11 mm glucose) for 30 days. In addition, weight gain negatively correlated with blood glucose level. The findings verified diabetes reversal in caprine islet recipient mice. A significant drop in non-fasting blood glucose level (from 23.3 ± 5.4 to 8.04 ± 0.44 mm) and simultaneous increase in serum insulin level (from 0.01 ± 0.001 to 0.56 ± 0.17 ?g/l) and body weights (from 23.64 ± 0.31 to 25.85 ± 0.34 g) were observed (P < 0.05). Immunohistochemical analysis verified insulin production in the transplanted islets. Conclusions Purified caprine islets were demonstrated to successfully sustain viability and functionality for controlling blood glucose levels in an immunosuppressed mouse model of diabetes. These results suggest the use of caprine islets as an addition to the supply of xenogeneic islets for diabetes research. PMID:24645790

  18. Insulin-independent reversal of type 1 diabetes in nonobese diabetic mice with brown adipose tissue transplant.

    PubMed

    Gunawardana, Subhadra C; Piston, David W

    2015-06-15

    Traditional therapies for type 1 diabetes (T1D) involve insulin replacement or islet/pancreas transplantation and have numerous limitations. Our previous work demonstrated the ability of embryonic brown adipose tissue (BAT) transplants to establish normoglycemia without insulin in chemically induced models of insulin-deficient diabetes. The current study sought to extend the technique to an autoimmune-mediated T1D model and document the underlying mechanisms. In nonobese diabetic (NOD) mice, BAT transplants result in complete reversal of T1D associated with rapid and long-lasting euglycemia. In addition, BAT transplants placed prior to the onset of diabetes on NOD mice can prevent or significantly delay the onset of diabetes. As with streptozotocin (STZ)-diabetic models, euglycemia is independent of insulin and strongly correlates with decrease of inflammation and increase of adipokines. Plasma insulin-like growth factor-I (IGF-I) is the first hormone to increase following BAT transplants. Adipose tissue of transplant recipients consistently express IGF-I compared with little or no expression in controls, and plasma IGF-I levels show a direct negative correlation with glucose, glucagon, and inflammatory cytokines. Adipogenic and anti-inflammatory properties of IGF-I may stimulate regeneration of new healthy white adipose tissue, which in turn secretes hypoglycemic adipokines that substitute for insulin. IGF-I can also directly decrease blood glucose through activating insulin receptor. These data demonstrate the potential for insulin-independent reversal of autoimmune-induced T1D with BAT transplants and implicate IGF-I as a likely mediator in the resulting equilibrium. PMID:25898954

  19. Impaired Coronary and Renal Vascular Function in Spontaneously Type 2 Diabetic Leptin-Deficient Mice

    PubMed Central

    Westergren, Helena U.; Grönros, Julia; Heinonen, Suvi E.; Miliotis, Tasso; Jennbacken, Karin; Sabirsh, Alan; Ericsson, Anette; Jönsson-Rylander, Ann-Cathrine; Svedlund, Sara; Gan, Li-Ming

    2015-01-01

    Background Type 2 diabetes is associated with macro- and microvascular complications in man. Microvascular dysfunction affects both cardiac and renal function and is now recognized as a main driver of cardiovascular mortality and morbidity. However, progression of microvascular dysfunction in experimental models is often obscured by macrovascular pathology and consequently demanding to study. The obese type 2 diabetic leptin-deficient (ob/ob) mouse lacks macrovascular complications, i.e. occlusive atherosclerotic disease, and may therefore be a potential model for microvascular dysfunction. The present study aimed to test the hypothesis that these mice with an insulin resistant phenotype might display microvascular dysfunction in both coronary and renal vascular beds. Methods and Results In this study we used non-invasive Doppler ultrasound imaging to characterize microvascular dysfunction during the progression of diabetes in ob/ob mice. Impaired coronary flow velocity reserve was observed in the ob/ob mice at 16 and 21 weeks of age compared to lean controls. In addition, renal resistivity index as well as pulsatility index was higher in the ob/ob mice at 21 weeks compared to lean controls. Moreover, plasma L-arginine was lower in ob/ob mice, while asymmetric dimethylarginine was unaltered. Furthermore, a decrease in renal vascular density was observed in the ob/ob mice. Conclusion In parallel to previously described metabolic disturbances, the leptin-deficient ob/ob mice also display cardiac and renal microvascular dysfunction. This model may therefore be suitable for translational, mechanistic and interventional studies to improve the understanding of microvascular complications in type 2 diabetes. PMID:26098416

  20. Gene expression microarray analysis of the sciatic nerve of mice with diabetic neuropathy.

    PubMed

    Zhang, Lei; Qu, Shen; Liang, Aibin; Jiang, Hong; Wang, Hao

    2015-02-01

    The present study aimed to explore novel target genes that regulate the development of diabetic neuropathy (DN) by analyzing gene expression profiles in the sciatic nerve of infected mice. The GSE11343 microarray dataset, which was downloaded from Gene Expression Omnibus, included data on 4 control samples and 5 samples from mice with diabetes induced by streptozotocin (STZ), 5 samples from normal mice treated with rosiglitazone (Rosi) and 5 samples from mice with diabetes induced by STZ and treated with Rosi. Differentially expressed genes (DEGs) between the different groups were identified using the substitution augmentation modification redefinition (SAMR) model. The Gene Ontology (GO) term and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed using the Database for Annotation, Visualization and Integrated Discovery (DAVID). Regulatory and protein?protein interaction networks were searched using BioCarta and STRING, respectively. The protein structures of potential regulatory genes were predicted using the SYBYL program. Compared with the controls, 1,384 DEGs were identified in the mice with STZ-induced diabetes and 7 DEGs were identified in the mice treated with Rosi. There were 518 DEGs identified between the mice in the STZ + Rosi and STZ groups. We identified 45 GO items, and the calmodulin nerve phosphatase and chemokine signaling pathways were identified as the main pathways. Three genes [myristoylated alanine-rich protein kinase C substrate (Marcks), GLI pathogenesis-related 2 (Glipr2) and centrosomal protein 170 kDa (Cep170)] were found to be co-regulated by both STZ and Rosi, the protein structure of which was predicted and certain binding activity to Rosi was docked. Our study demonstrates that the Marcks, Glipr2 and Cep170 genes may be underlying drug targets in the treatment of DN. PMID:25435094

  1. INFLUENCE OF TYPE II DIABETES AND OBESITY ON THE DISPOSITION AND ELIMINATION OF TCDD IN MICE

    EPA Science Inventory

    INFLUENCE OF TYPE II DIABETES AND OBESITY ON THE DISPOSTION AND ELIMINATION OF TCDD IN MICE. MJ DeVito', JJ Diliberto', DG Ross', C Emond2, VM Richardson', and LS Birnbaum', 'ETD, NHEERL, ORD, US EPA, RTP, NC, 27711, USA, 2National Research Council.
    One possible explanation fo...

  2. Hypoglycemic Effect of Jicama (Pachyrhizus erosus) Extract on Streptozotocin-Induced Diabetic Mice.

    PubMed

    Park, Chan Joo; Han, Ji-Sook

    2015-06-01

    The purpose of this research was to investigate the inhibitory effect of jicama extract on ?-glucosidase activity, ?-amylase activity, and postprandial hyperglycemia in streptozotocin (STZ)-induced diabetic mice. Jicama extract showed prominent inhibitory effects against ?-glucosidase and ?-amylase. The IC50 values of jicama extract against ?-glucosidase and ?-amylase were 0.083±0.004 and 0.091±0.017 mg/mL, respectively. The increase in postprandial blood glucose levels was more significantly suppressed in the jicama extract-administered group than in the control group of both STZ-induced diabetic and normal mice. Blood glucose levels of the control group increased to 383.75±11.54 and 402.50±15.32 mg/dL at 30 and 60 min after a meal and decreased to 349.67±11.62 mg/dL at 120 min. However, postprandial blood glucose levels were significantly decreased, when diabetic mice were fed with jicama extract (342.00±15.73, 367.00±13.00, and 329.67±12.43 mg/dL at 30, 60, and 120 min, respectively). Furthermore, the area under the curve was significantly decreased with jicama extract administration in diabetic mice (P<0.05). Therefore, these results indicate that jicama extract may help decrease postprandial blood glucose level by inhibiting ?-glucosidase. PMID:26175995

  3. Hypoglycemic Effect of Jicama (Pachyrhizus erosus) Extract on Streptozotocin-Induced Diabetic Mice

    PubMed Central

    Park, Chan Joo; Han, Ji-Sook

    2015-01-01

    The purpose of this research was to investigate the inhibitory effect of jicama extract on ?-glucosidase activity, ?-amylase activity, and postprandial hyperglycemia in streptozotocin (STZ)-induced diabetic mice. Jicama extract showed prominent inhibitory effects against ?-glucosidase and ?-amylase. The IC50 values of jicama extract against ?-glucosidase and ?-amylase were 0.083±0.004 and 0.091±0.017 mg/mL, respectively. The increase in postprandial blood glucose levels was more significantly suppressed in the jicama extract-administered group than in the control group of both STZ-induced diabetic and normal mice. Blood glucose levels of the control group increased to 383.75±11.54 and 402.50±15.32 mg/dL at 30 and 60 min after a meal and decreased to 349.67±11.62 mg/dL at 120 min. However, postprandial blood glucose levels were significantly decreased, when diabetic mice were fed with jicama extract (342.00±15.73, 367.00±13.00, and 329.67±12.43 mg/dL at 30, 60, and 120 min, respectively). Furthermore, the area under the curve was significantly decreased with jicama extract administration in diabetic mice (P<0.05). Therefore, these results indicate that jicama extract may help decrease postprandial blood glucose level by inhibiting ?-glucosidase. PMID:26175995

  4. The dipeptidyl peptidase-4 inhibitor sitagliptin suppresses mouse colon tumorigenesis in type 2 diabetic mice.

    PubMed

    Yorifuji, Naoki; Inoue, Takuya; Iguchi, Munetaka; Fujiwara, Kaori; Kakimoto, Kazuki; Nouda, Sadaharu; Okada, Toshihiko; Kawakami, Ken; Abe, Yosuke; Takeuchi, Toshihisa; Higuchi, Kazuhide

    2016-02-01

    Patients with type 2 diabetes mellitus are known to have an increased risk of colorectal neoplasia. Dipeptidyl peptidase-4 (DPP-4) inhibitors have been used as a new therapeutic tool for type 2 diabetes. Since the substrates for DPP-4 include intestinotrophic hormones and chemokines such as GLP-2 and stromal cell-derived factor-1 (SDF-1), which are associated with tumor progression, DPP-4 inhibitors may increase the risk of colorectal tumors. However, the influence of DPP-4 inhibitors on colorectal neoplasia in patients with type 2 diabetes remains unknown. In the present study, we show that long-term administration of a DPP-4 inhibitor, sitagliptin (STG), suppressed colon carcinogenesis in leptin-deficient (ob/ob) C57BL/6J mice. Colonic mucosal concentrations of glucagon?like peptide-1 (GLP-1) and GLP-2 were significantly elevated in the ob/ob mice. However, mucosal GLP concentrations and the plasma level of SDF-1 were not affected by the administration of STG. Real?time PCR analysis revealed that colonic mucosal IL-6 mRNA expression, which was significantly upregulated in the ob/ob mice, was significantly suppressed by the long-term administration of STG. These results suggest that a DPP-4 inhibitor may suppress colon carcinogenesis in mice with type 2 diabetes in a GLP-independent manner. Since DPP-4 has multiple biological functions, further studies analyzing other factors related to colon carcinogenesis are needed. PMID:26573958

  5. Sustained Inflammasome Activity in Macrophages Impairs Wound Healing in Type 2 Diabetic Humans and Mice

    PubMed Central

    Mirza, Rita E.; Fang, Milie M.; Weinheimer-Haus, Eileen M.; Ennis, William J.; Koh, Timothy J.

    2014-01-01

    The hypothesis of this study was that sustained activity of the Nod-like receptor protein (NLRP)-3 inflammasome in wounds of diabetic humans and mice contributes to the persistent inflammatory response and impaired healing characteristic of these wounds. Macrophages (Mp) isolated from wounds on diabetic humans and db/db mice exhibited sustained inflammasome activity associated with low level of expression of endogenous inflammasome inhibitors. Soluble factors in the biochemical milieu of these wounds are sufficient to activate the inflammasome, as wound-conditioned medium activates caspase-1 and induces release of interleukin (IL)-1? and IL-18 in cultured Mp via a reactive oxygen species–mediated pathway. Importantly, inhibiting inflammasome activity in wounds of db/db mice using topical application of pharmacological inhibitors improved healing of these wounds, induced a switch from proinflammatory to healing-associated Mp phenotypes, and increased levels of prohealing growth factors. Furthermore, data generated from bone marrow–transfer experiments from NLRP-3 or caspase-1 knockout to db/db mice indicated that blocking inflammasome activity in bone marrow cells is sufficient to improve healing. Our findings indicate that sustained inflammasome activity in wound Mp contributes to impaired early healing responses of diabetic wounds and that the inflammasome may represent a new therapeutic target for improving healing in diabetic individuals. PMID:24194505

  6. Impaired adiponectin signaling contributes to disturbed catabolism of branched-chain amino acids in diabetic mice.

    PubMed

    Lian, Kun; Du, Chaosheng; Liu, Yi; Zhu, Di; Yan, Wenjun; Zhang, Haifeng; Hong, Zhibo; Liu, Peilin; Zhang, Lijian; Pei, Haifeng; Zhang, Jinglong; Gao, Chao; Xin, Chao; Cheng, Hexiang; Xiong, Lize; Tao, Ling

    2015-01-01

    The branched-chain amino acids (BCAA) accumulated in type 2 diabetes are independent contributors to insulin resistance. The activity of branched-chain ?-keto acid dehydrogenase (BCKD) complex, rate-limiting enzyme in BCAA catabolism, is reduced in diabetic states, which contributes to elevated BCAA concentrations. However, the mechanisms underlying decreased BCKD activity remain poorly understood. Here, we demonstrate that mitochondrial phosphatase 2C (PP2Cm), a newly identified BCKD phosphatase that increases BCKD activity, was significantly downregulated in ob/ob and type 2 diabetic mice. Interestingly, in adiponectin (APN) knockout (APN(-/-)) mice fed with a high-fat diet (HD), PP2Cm expression and BCKD activity were significantly decreased, whereas BCKD kinase (BDK), which inhibits BCKD activity, was markedly increased. Concurrently, plasma BCAA and branched-chain ?-keto acids (BCKA) were significantly elevated. APN treatment markedly reverted PP2Cm, BDK, BCKD activity, and BCAA and BCKA levels in HD-fed APN(-/-) and diabetic animals. Additionally, increased BCKD activity caused by APN administration was partially but significantly inhibited in PP2Cm knockout mice. Finally, APN-mediated upregulation of PP2Cm expression and BCKD activity were abolished when AMPK was inhibited. Collectively, we have provided the first direct evidence that APN is a novel regulator of PP2Cm and systematic BCAA levels, suggesting that targeting APN may be a pharmacological approach to ameliorating BCAA catabolism in the diabetic state. PMID:25071024

  7. Modulating Notch Signaling to Enhance Neovascularization and Reperfusion in Diabetic Mice

    PubMed Central

    Cao, Lan; Arany, Praveen; Kim, Jaeyun; Rivera-Feliciano, José; Wang, Yuan-Shuo; He, Zhiheng; Rask-Madsen, Christian; King, George L.; Mooney, David J.

    2010-01-01

    Diabetes can diminish the responsiveness to angiogenic factors (e.g., VEGF) important for wound healing and the treatment of ischemic diseases, and this study investigated the hypothesis that this effect can be reversed by altering Notch signaling. Aortic endothelial cells (ECs) isolated from diabetic mice demonstrated reduced sprouting capability in vitro, but adding a Notch inhibitor (DAPT) led to cell-density and VEGF-dose dependent enhancement of proliferation, migration and sprouting, in both 2-D and 3-D cultures, as compared to VEGF alone. The in vivo effects of VEGF and DAPT were tested in the ischemic hindlimbs of diabetic mice. Combining VEGF and DAPT delivery resulted in increased blood vessel density (~150%) and improved tissue perfusion (~160%), as compared to VEGF alone. To examine if DAPT would interfere with vessel maturation, DAPT was also delivered with a combination of VEGF and platelet derived growth factor (PDGF). DAPT and PDGF did not interfere with the effects of the other, and highly functional and mature networks of vessels could be formed with appropriate delivery. In summary, modulating Notch signaling enhances neovascularization and perfusion recovery in diabetic mice suffering from ischemia, suggesting this approach could have utility for human diabetics. PMID:20800279

  8. Hypoglycemic and Hypolipidemic Effects of Ethanolic Extract of Mirabilis jalapa L. Root on Normal and Diabetic Mice

    PubMed Central

    Zhou, Ji-Yin; Zhou, Shi-Wen; Zeng, Sheng-Ya; Zhou, Jian-Yun; Jiang, Ming-Jin; He, Yan

    2012-01-01

    The present study investigated the insulin sensitivity, hypoglycemic, and hypolipidemic activities of ethanolic extract of Mirabilis jalapa L. root (EEM) in normal and diabetic mice. After induction of diabetes with streptozotocin, both normal and diabetic mice were singly or repeatedly for 28 days administrated with EEM at doses of 2, 4, 8?g/kg, respectively. Before induction of diabetes, mice were administrated with EEM at doses of 2, 4, 8?g/kg for 14 days and were injected with streptozotocin and continued on EEM administration for another 28 days. Both after and before induction of diabetes, repeated administration with 4, 8?g/kg EEM continually lowered blood glucose level, decreased serum insulin level and improved insulin sensitivity index, and lowered serum total cholesterol, triglyceride levels and triglyceride content in liver and skeletal muscle, and increased glycogen content in these tissues; but repeated administration had no influence on those indexes of normal mice. Single administration with EEM (4, 8?g/kg) showed hypoglycemic effect in oral glucose tolerance test in normal and diabetic mice. Single administration with EEM had no hypoglycemic and hypolipidemic effects on normal and diabetic mice. These results suggest that EEM possesses both potential insulin sensitivity, hypoglycemic, and hypolipidemic effects on diabetes. PMID:22474494

  9. Resveratrol-enhanced autophagic flux ameliorates myocardial oxidative stress injury in diabetic mice.

    PubMed

    Wang, Bo; Yang, Qing; Sun, Yuan-yuan; Xing, Yi-fan; Wang, Ying-bin; Lu, Xiao-ting; Bai, Wen-wu; Liu, Xiao-qiong; Zhao, Yu-xia

    2014-08-01

    Autophagic dysfunction is observed in diabetes mellitus. Resveratrol has a beneficial effect on diabetic cardiomyopathy. Whether the resveratrol-induced improvement in cardiac function in diabetes is via regulating autophagy remains unclear. We investigated the mechanisms underlying resveratrol-mediated protection against heart failure in diabetic mice, with a focus on the role of sirtuin 1 (SIRT1) in regulating autophagic flux. Diabetic cardiomyopathy in mice was induced by streptozotocin (STZ). Long-term resveratrol treatment improved cardiac function, ameliorated oxidative injury and reduced apoptosis in the diabetic mouse heart. Western blot analysis revealed that resveratrol decreased p62 protein expression and promoted SIRT1 activity and Rab7 expression. Inhibiting autophagic flux with bafilomycin A1 increased diabetic mouse mortality and attenuated resveratrol-induced down-regulation of p62, but not SIRT1 activity or Rab7 expression in diabetic mouse hearts. In cultured H9C2 cells, redundant or overactive H?O? increased p62 and cleaved caspase 3 expression as well as acetylated forkhead box protein O1 (FOXO1) and inhibited SIRT1 expression. Sirtinol, SIRT1 and Rab7 siRNA impaired the resveratrol amelioration of dysfunctional autophagic flux and reduced apoptosis under oxidative conditions. Furthermore, resveratrol enhanced FOXO1 DNA binding at the Rab7 promoter region through a SIRT1-dependent pathway. These results highlight the role of the SIRT1/FOXO1/Rab7 axis in the effect of resveratrol on autophagic flux in vivo and in vitro, which suggests a therapeutic strategy for diabetic cardiomyopathy. PMID:24889822

  10. Left ventricular dysfunction with reduced functional cardiac reserve in diabetic and non-diabetic LDL-receptor deficient apolipoprotein B100-only mice

    PubMed Central

    2011-01-01

    Background Lack of suitable mouse models has hindered the studying of diabetic macrovascular complications. We examined the effects of type 2 diabetes on coronary artery disease and cardiac function in hypercholesterolemic low-density lipoprotein receptor-deficient apolipoprotein B100-only mice (LDLR-/-ApoB100/100). Methods and results 18-month-old LDLR-/-ApoB100/100 (n = 12), diabetic LDLR-/-ApoB100/100 mice overexpressing insulin-like growth factor-II (IGF-II) in pancreatic beta cells (IGF-II/LDLR-/-ApoB100/100, n = 14) and age-matched C57Bl/6 mice (n = 15) were studied after three months of high-fat Western diet. Compared to LDLR-/-ApoB100/100 mice, diabetic IGF-II/LDLR-/-ApoB100/100 mice demonstrated more calcified atherosclerotic lesions in aorta. However, compensatory vascular enlargement was similar in both diabetic and non-diabetic mice with equal atherosclerosis (cross-sectional lesion area ~60%) and consequently the lumen area was preserved. In coronary arteries, both hypercholesterolemic models showed significant stenosis (~80%) despite positive remodeling. Echocardiography revealed severe left ventricular systolic dysfunction and anteroapical akinesia in both LDLR-/-ApoB100/100 and IGF-II/LDLR-/-ApoB100/100 mice. Myocardial scarring was not detected, cardiac reserve after dobutamine challenge was preserved and ultrasructural changes revealed ischemic yet viable myocardium, which together with coronary artery stenosis and slightly impaired myocardial perfusion suggest myocardial hibernation resulting from chronic hypoperfusion. Conclusions LDLR-/-ApoB100/100 mice develop significant coronary atherosclerosis, severe left ventricular dysfunction with preserved but diminished cardiac reserve and signs of chronic myocardial hibernation. However, the cardiac outcome is not worsened by type 2 diabetes, despite more advanced aortic atherosclerosis in diabetic animals. PMID:21718508

  11. Anti-oxidant effect of gold nanoparticles restrains hyperglycemic conditions in diabetic mice

    PubMed Central

    2010-01-01

    Background Oxidative stress is imperative for its morbidity towards diabetic complications, where abnormal metabolic milieu as a result of hyperglycemia, leads to the onset of several complications. A biological antioxidant capable of inhibiting oxidative stress mediated diabetic progressions; during hyperglycemia is still the need of the era. The current study was performed to study the effect of biologically synthesized gold nanoparticles (AuNPs) to control the hyperglycemic conditions in streptozotocin induced diabetic mice. Results The profound control of AuNPs over the anti oxidant enzymes such as GSH, SOD, Catalase and GPx in diabetic mice to normal, by inhibition of lipid peroxidation and ROS generation during hyperglycemia evidence their anti-oxidant effect during hyperglycemia. The AuNPs exhibited an insistent control over the blood glucose level, lipids and serum biochemical profiles in diabetic mice near to the control mice provokes their effective role in controlling and increasing the organ functions for better utilization of blood glucose. Histopathological and hematological studies revealed the non-toxic and protective effect of the gold nanoparticles over the vital organs when administered at dosage of 2.5 mg/kilogram.body.weight/day. ICP-MS analysis revealed the biodistribution of gold nanoparticles in the vital organs showing accumulation of AuNPs in the spleen comparatively greater than other organs. Conclusion The results obtained disclose the effectual role of AuNPs as an anti-oxidative agent, by inhibiting the formation of ROS, scavenging free radicals; thus increasing the anti-oxidant defense enzymes and creating a sustained control over hyperglycemic conditions which consequently evoke the potential of AuNPs as an economic therapeutic remedy in diabetic treatments and its complications. PMID:20630072

  12. Coronary endothelial dysfunction and mitochondrial reactive oxygen species in type 2 diabetic mice

    PubMed Central

    Cho, Young-Eun; Basu, Aninda; Dai, Anzhi; Heldak, Michael

    2013-01-01

    Endothelial cell (EC) dysfunction is implicated in cardiovascular diseases, including diabetes. The decrease in nitric oxide (NO) bioavailability is the hallmark of endothelial dysfunction, and it leads to attenuated vascular relaxation and atherosclerosis followed by a decrease in blood flow. In the heart, decreased coronary blood flow is responsible for insufficient oxygen supply to cardiomyocytes and, subsequently, increases the incidence of cardiac ischemia. In this study we investigate whether and how reactive oxygen species (ROS) in mitochondria contribute to coronary endothelial dysfunction in type 2 diabetic (T2D) mice. T2D was induced in mice by a high-fat diet combined with a single injection of low-dose streptozotocin. ACh-induced vascular relaxation was significantly attenuated in coronary arteries (CAs) from T2D mice compared with controls. The pharmacological approach reveals that NO-dependent, but not hyperpolarization- or prostacyclin-dependent, relaxation was decreased in CAs from T2D mice. Attenuated ACh-induced relaxation in CAs from T2D mice was restored toward control level by treatment with mitoTempol (a mitochondria-specific O2? scavenger). Coronary ECs isolated from T2D mice exhibited a significant increase in mitochondrial ROS concentration and decrease in SOD2 protein expression compared with coronary ECs isolated from control mice. Furthermore, protein ubiquitination of SOD2 was significantly increased in coronary ECs isolated from T2D mice. These results suggest that augmented SOD2 ubiquitination leads to the increase in mitochondrial ROS concentration in coronary ECs from T2D mice and attenuates coronary vascular relaxation in T2D mice. PMID:23986204

  13. Prevention of Autoimmune Diabetes and Induction of ?-Cell Proliferation in NOD Mice by Hyperbaric Oxygen Therapy

    PubMed Central

    Faleo, Gaetano; Fotino, Carmen; Bocca, Nicola; Molano, R. Damaris; Zahr-Akrawi, Elsie; Molina, Judith; Villate, Susana; Umland, Oliver; Skyler, Jay S.; Bayer, Allison L.; Ricordi, Camillo; Pileggi, Antonello

    2012-01-01

    We evaluated the effects of hyperbaric oxygen therapy (HOT) on autoimmune diabetes development in nonobese diabetic (NOD) mice. Animals received no treatment or daily 60-min HOT 100% oxygen (HOT-100%) at 2.0 atmospheres absolute and were monitored for diabetes onset, insulitis, infiltrating cells, immune cell function, and ?-cell apoptosis and proliferation. Cyclophosphamide-induced diabetes onset was reduced from 85.3% in controls to 48% after HOT-100% (P < 0.005) and paralleled by lower insulitis. Spontaneous diabetes incidence reduced from 85% in controls to 65% in HOT-100% (P = 0.01). Prediabetic mice receiving HOT-100% showed lower insulitis scores, reduced T-cell proliferation upon stimulation in vitro (P < 0.03), increased CD62L expression in T cells (P < 0.04), reduced costimulation markers (CD40, DC80, and CD86), and reduced major histocompatibility complex class II expression in dendritic cells (DCs) (P < 0.025), compared with controls. After autoimmunity was established, HOT was less effective. HOT-100% yielded reduced apoptosis (transferase-mediated dUTP nick-end labeling-positive insulin-positive cells; P < 0.01) and increased proliferation (bromodeoxyuridine incorporation; P < 0.001) of insulin-positive cells compared with controls. HOT reduces autoimmune diabetes incidence in NOD mice via increased resting T cells and reduced activation of DCs with preservation of ?-cell mass resulting from decreased apoptosis and increased proliferation. The safety profile and noninvasiveness makes HOT an appealing adjuvant therapy for diabetes prevention and intervention trials. PMID:22566533

  14. TLR4 antagonist attenuates atherogenesis in LDL receptor-deficient mice with diet-induced type 2 diabetes.

    PubMed

    Lu, Zhongyang; Zhang, Xiaoming; Li, Yanchun; Lopes-Virella, Maria F; Huang, Yan

    2015-11-01

    Although a large number of studies have well documented a key role of toll-like receptor (TLR)4 in atherosclerosis, it remains undetermined if TLR4 antagonist attenuates atherogenesis in mouse model for type 2 diabetes. In this study, we induced type 2 diabetes in low-density lipoprotein receptor-deficient (LDLR(-/-)) mice by high-fat diet (HFD). At 8 weeks old, 20 mice were fed HFD and 20 mice fed regular chow (RC) for 24 weeks. In the last 10 weeks, half HFD-fed mice and half RC-fed mice were treated with Rhodobacter sphaeroides lipopolysaccharide (Rs-LPS), an established TLR4 antagonist. After the treatment, atherosclerotic lesions in aortas were analyzed. Results showed that the HFD significantly increased bodyweight, glucose, lipids including total cholesterol, triglycerides and free fatty acids, and insulin resistance, indicating that the HFD induced type 2 diabetes in LDLR(-/-) mice. Results also showed that Rs-LPS had no effect on HFD-increased metabolic parameters in both nondiabetic and diabetic mice. Lipid staining of aortas and histological analysis of cross-sections of aortic roots showed that diabetes increased atherosclerotic lesions, but Rs-LPS attenuated atherogenesis in diabetic mice. Furthermore, immunohistochemical studies showed that Rs-LPS reduced infiltration of monocytes/macrophages and expression of interleukin (IL)-6 and matrix metalloproteinase-9 in atherosclerotic lesions of diabetic mice. Finally, the antagonistic effect of Rs-LPS on TLR4 was demonstrated by our in vitro studies showing that Rs-LPS inhibited IL-6 secretion from macrophages and endothelial cells stimulated by LPS or LPS plus saturated fatty acid palmitate. Taken together, our study demonstrated that TLR4 antagonist was capable of attenuating vascular inflammation and atherogenesis in mice with HFD-induced type 2 diabetes. PMID:26162692

  15. The Induction of Heme Oxygenase 1 Decreases Painful Diabetic Neuropathy and Enhances the Antinociceptive Effects of Morphine in Diabetic Mice.

    PubMed

    Castany, Sílvia; Carcolé, Mireia; Leánez, Sergi; Pol, Olga

    2016-01-01

    Painful diabetic neuropathy is a common complication of diabetes mellitus which is poorly controlled by conventional analgesics. This study investigates if treatment with an heme oxygenase 1 (HO-1) inducer, cobalt protoporphyrin IX (CoPP), could modulate the allodynia and hyperalgesia induced by diabetes and enhanced the antinociceptive effects of morphine. In a diabetic mice model induced by the injection of streptozotocin (STZ), we evaluated the antiallodynic and antihyperalgesic effects produced by the intraperitoneal administration of 5 and 10 mg/kg of CoPP at several days after its administration. The antinociceptive actions produced by the systemic administration of morphine alone or combined with CoPP were also evaluated. In addition, the effects of CoPP treatment on the expression of HO-1, the microglial activation marker (CD11b/c), the inducible nitric oxide synthase (NOS2) and ?-opioid receptors (MOR), were also assessed. Our results showed that the administration of 10 mg/kg of CoPP during 5 consecutive days completely blocked the mechanical and thermal hypersensitivity induced by diabetes. These effects are accompanied by the increased spinal cord, dorsal root ganglia and sciatic nerve protein levels of HO-1. In addition, the STZ-induced activation of microglia and overexpression of NOS2 in the spinal cord were inhibited by CoPP treatment. Furthermore, the antinociceptive effects of morphine were enhanced by CoPP treatment and reversed by the administration of an HO-1 inhibitor, tin protoporphyrin IX (SnPP). The spinal cord expression of MOR was also increased by CoPP treatment in diabetic mice. In conclusion, our data provide the first evidence that the induction of HO-1 attenuated STZ-induced painful diabetic neuropathy and enhanced the antinociceptive effects of morphine via inhibition of microglia activation and NOS2 overexpression as well as by increasing the spinal cord levels of MOR. This study proposes the administration of CoPP alone or combined with morphine as an interesting therapeutic approach for the treatment of painful diabetic neuropathy. PMID:26730587

  16. Photobiomodulation Mitigates Diabetes-Induced Retinopathy by Direct and Indirect Mechanisms: Evidence from Intervention Studies in Pigmented Mice

    PubMed Central

    Liu, Haitao; Patel, Shyam; Roberts, Robin; Berkowitz, Bruce A.; Kern, Timothy S.

    2015-01-01

    Objective Daily application of far-red light from the onset of diabetes mitigated diabetes-induced abnormalities in retinas of albino rats. Here, we test the hypothesis that photobiomodulation (PBM) is effective in diabetic, pigmented mice, even when delayed until weeks after onset of diabetes. Direct and indirect effects of PBM on the retina also were studied. Methods Diabetes was induced in C57Bl/6J mice using streptozotocin. Some diabetics were exposed to PBM therapy (4 min/day; 670 nm) daily. In one study, mice were diabetic for 4 weeks before initiation of PBM for an additional 10 weeks. Retinal oxidative stress, inflammation, and retinal function were measured. In some mice, heads were covered with a lead shield during PBM to prevent direct illumination of the eye, or animals were treated with an inhibitor of heme oxygenase-1. In a second study, PBM was initiated immediately after onset of diabetes, and administered daily for 2 months. These mice were examined using manganese-enhanced MRI to assess effects of PBM on transretinal calcium channel function in vivo. Results PBM intervention improved diabetes-induced changes in superoxide generation, leukostasis, expression of ICAM-1, and visual performance. PBM acted in part remotely from the retina because the beneficial effects were achieved even with the head shielded from the light therapy, and because leukocyte-mediated cytotoxicity of retinal endothelial cells was less in diabetics treated with PBM. SnPP+PBM significantly reduced iNOS expression compared to PBM alone, but significantly exacerbated leukostasis. In study 2, PBM largely mitigated diabetes-induced retinal calcium channel dysfunction in all retinal layers. Conclusions PBM induces retinal protection against abnormalities induced by diabetes in pigmented animals, and even as an intervention. Beneficial effects on the retina likely are mediated by both direct and indirect mechanisms. PBM is a novel non-pharmacologic treatment strategy to inhibit early changes of diabetic retinopathy. PMID:26426815

  17. Hypoglycemic and antioxidant potential of coconut water in experimental diabetes.

    PubMed

    Preetha, P P; Devi, V Girija; Rajamohan, T

    2012-07-01

    Coconut water is a natural nutritious beverage that contains several biologically active compounds. The present study aims to evaluate the hypoglycemic and antioxidant effects of mature coconut water (MCW) on alloxan-induced diabetes in experimental rats. The experimental animals were divided into four groups - normal control, normal rats treated with MCW, diabetic control and diabetic rats treated with MCW. The blood glucose, plasma insulin, hemoglobin, glycated hemoglobin, activities of the various antioxidant enzymes (catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase) and lipid peroxidation markers (malondialdehyde, hydroperoxides and conjugated dienes) were evaluated in all the groups. The results indicate that the diabetic animals treated with MCW had decreased blood glucose levels and reduced oxidative stress induced by alloxan, which was evident from the increased activities of the antioxidant enzymes and the decreased levels of the lipid peroxidation products. The overall results indicate that MCW significantly attenuated hyperglycemia and oxidative stress in alloxan-induced diabetic rats, indicating the therapeutic potential of MCW. PMID:22576019

  18. Effect of corosolic acid on dietary hypercholesterolemia and hepatic steatosis in KK-Ay diabetic mice.

    PubMed

    Takagi, Satoshi; Miura, Toshihiro; Ishihara, Eriko; Ishida, Torao; Chinzei, Yasuo

    2010-08-01

    Corosolic acid (CA), contained in the leaves of the banaba plant (Lagerstroemia speciosa L.), is a pentacyclic triterpene, and has hypoglycemic effects. The effects of CA on dietary hypercholesterolemia and hepatic steatosis were assessed in KK-Ay mice, an animal model of type 2 diabetes. Two kinds of high cholesterol diet with or without 0.023% CA, were prepared for the study. KK-Ay mice were fed a normal diet (controls), the high cholesterol diet with CA (CA-mice) or that without CA (HC-mice) for 10 weeks. CA inhibited the mean blood cholesterol level by 32% (P<0.05) and the liver cholesterol content by 46% (P<0.05) compared with those of HC-mice 10 weeks after the start of dietary intake. Acutely, CA inhibited the mean blood cholesterol level 4 h after the administration of a high-cholesterol cocktail in an oral cholesterol-loading test, compared with that of control mice (P<0.05). These results suggest that CA has some direct effects on the cholesterol absorption process in the small intestine. CA may inhibit the activity of cholesterol acyltransferase, which acts in the re-esterification of cholesterol in the small intestine, in type 2 diabetes. PMID:20834178

  19. Japanese herbal medicine TJ-48 prevents autoimmune diabetes in NOD mice.

    PubMed

    Ikemoto, Tetsuya; Sugimoto, Koji; Takita, Morihito; Shimoda, Masayuki; Noguchi, Hirofumi; Naziruddin, Bashoo; Levy, Marlon F; Shimada, Mitsuo; Matsumoto, Shinichi

    2011-01-01

    Type 1 diabetes mellitus (T1DM) is mainly caused by CD8(+) cytotoxic T cell infiltration into islets. Recently, the role of regulatory T cells (Tregs) in the prevention of the onset of T1DM was reported. We reported that TJ-48, a common Japanese herbal medicine, decreased Treg population in cancer patients, thus we investigated whether TJ-48 had an influence on T1DM onset using NOD mice. In the TJ-48 group, TJ-48 (2.0g/kg/day) was administered in the drinking water for NOD mice from three weeks of age to 20 weeks of age. Their body weight and fast blood glucose (FBG) were measured every week. Histology (Hematoxylin-Eosin staining) was investigated every month. Lymphocyte profiles were investigated every month with FACS. The results were compared to the age-matched NOD mice control group. FBG of the control group mice showed diabetic status of 66.7% at 18 weeks of age. On the other hand, the TJ-48 group mice showed diabetic status of 16.7% at 18 weeks of age (p = 1.905E-06). There were no significant differences in general conditions or body weight between the two groups. Lymphocyte infiltrations into islets were dramatically suppressed in the TJ-48 group. The effect of TJ-48 on decreasing Tregs was less apparent in the NOD mice model. TJ-48 inhibited lymphocyte infiltrations into islets, which led to preventing the onset of T1DM in NOD mice. PMID:21721154

  20. Aerobic interval training reduces inducible ventricular arrhythmias in diabetic mice after myocardial infarction.

    PubMed

    Rolim, Natale; Skårdal, Kristine; Høydal, Morten; Sousa, Mirta M L; Malmo, Vegard; Kaurstad, Guri; Ingul, Charlotte B; Hansen, Harald E M; Alves, Marcia N; Thuen, Marte; Haraldseth, Olav; Brum, Patricia C; Slupphaug, Geir; Loennechen, Jan Pål; Stølen, Tomas; Wisløff, Ulrik

    2015-01-01

    Diabetes mellitus (DM) increases the risk of heart failure after myocardial infarction (MI), and aggravates ventricular arrhythmias in heart failure patients. Although exercise training improves cardiac function in heart failure, it is still unclear how it benefits the diabetic heart after MI. To study the effects of aerobic interval training on cardiac function, susceptibility to inducible ventricular arrhythmias and cardiomyocyte calcium handling in DM mice after MI (DM-MI). Male type 2 DM mice (C57BLKS/J Lepr (db) /Lepr (db) ) underwent MI or sham surgery. One group of DM-MI mice was submitted to aerobic interval training running sessions during 6 weeks. Cardiac function and structure were assessed by echocardiography and magnetic resonance imaging, respectively. Ventricular arrhythmias were induced by high-frequency cardiac pacing in vivo. Protein expression was measured by Western blot. DM-MI mice displayed increased susceptibility for inducible ventricular arrhythmias and impaired diastolic function when compared to wild type-MI, which was associated with disruption of cardiomyocyte calcium handling and increased calcium leak from the sarcoplasmic reticulum. High-intensity exercise recovered cardiomyocyte function in vitro, reduced sarcoplasmic reticulum diastolic calcium leak and significantly reduced the incidence of inducible ventricular arrhythmias in vivo in DM-MI mice. Exercise training also normalized the expression profile of key proteins involved in cardiomyocyte calcium handling, suggesting a potential molecular mechanism for the benefits of exercise in DM-MI mice. High-intensity aerobic exercise training recovers cardiomyocyte function and reduces inducible ventricular arrhythmias in infarcted diabetic mice. PMID:26112154

  1. Knockout Mice Challenge our Concepts of Glucose Homeostasis and the Pathogenesis of Diabetes

    PubMed Central

    2003-01-01

    A central component of type 2 diabetes and the metabolic syndrome is insulin resistance. Insulin exerts a multifaceted and highly integrated series of actions via its intracellular signaling systems. Generation of mice carrying null mutations of the genes encoding proteins in the insulin signaling pathway provides a unique approach to determining the role of individual proteins in the molecular mechanism of insulin action and the pathogenesis of insulin resistance and diabetes. The role of the four major insulin receptor substrates (IRS1-4) in insulin and IGF-1 signaling have been examined by creating mice with targeted gene knockouts. Each produces a unique phenotype, indicating the complementary role of these signaling components. Combined heterozygous defects often produce synergistic or epistatic effects, although the final severity of the phenotype depends on the genetic background of the mice. Conditional knockouts of the insulin receptor have also been created using the Cre-lox system. These tissue specific knockouts have provide unique insights into the control of glucose homeostasis and the pathogenesis of type 2 diabetes, and have led to development of new hypotheses about the nature of the insulin action and development of diabetes. PMID:15061645

  2. Metabonomic analysis of potential biomarkers and drug targets involved in diabetic nephropathy mice

    PubMed Central

    Wei, Tingting; Zhao, Liangcai; Jia, Jianmin; Xia, Huanhuan; Du, Yao; Lin, Qiuting; Lin, Xiaodong; Ye, Xinjian; Yan, Zhihan; Gao, Hongchang

    2015-01-01

    Diabetic nephropathy (DN) is one of the lethal manifestations of diabetic systemic microvascular disease. Elucidation of characteristic metabolic alterations during diabetic progression is critical to understand its pathogenesis and identify potential biomarkers and drug targets involved in the disease. In this study, 1H nuclear magnetic resonance (1H NMR)-based metabonomics with correlative analysis was performed to study the characteristic metabolites, as well as the related pathways in urine and kidney samples of db/db diabetic mice, compared with age-matched wildtype mice. The time trajectory plot of db/db mice revealed alterations, in an age-dependent manner, in urinary metabolic profiles along with progression of renal damage and dysfunction. Age-dependent and correlated metabolite analysis identified that cis-aconitate and allantoin could serve as biomarkers for the diagnosis of DN. Further correlative analysis revealed that the enzymes dimethylarginine dimethylaminohydrolase (DDAH), guanosine triphosphate cyclohydrolase I (GTPCH I), and 3-hydroxy-3-methylglutaryl-CoA lyase (HMG-CoA lyase) were involved in dimethylamine metabolism, ketogenesis and GTP metabolism pathways, respectively, and could be potential therapeutic targets for DN. Our results highlight that metabonomic analysis can be used as a tool to identify potential biomarkers and novel therapeutic targets to gain a better understanding of the mechanisms underlying the initiation and progression of diseases. PMID:26149603

  3. Metabolic stress–induced activation of FoxO1 triggers diabetic cardiomyopathy in mice

    PubMed Central

    Battiprolu, Pavan K.; Hojayev, Berdymammet; Jiang, Nan; Wang, Zhao V.; Luo, Xiang; Iglewski, Myriam; Shelton, John M.; Gerard, Robert D.; Rothermel, Beverly A.; Gillette, Thomas G.; Lavandero, Sergio; Hill, Joseph A.

    2012-01-01

    The leading cause of death in diabetic patients is cardiovascular disease; diabetic cardiomyopathy is typified by alterations in cardiac morphology and function, independent of hypertension or coronary disease. However, the molecular mechanism that links diabetes to cardiomyopathy is incompletely understood. Insulin resistance is a hallmark feature of diabetes, and the FoxO family of transcription factors, which regulate cell size, viability, and metabolism, are established targets of insulin and growth factor signaling. Here, we set out to evaluate a possible role of FoxO proteins in diabetic cardiomyopathy. We found that FoxO proteins were persistently activated in cardiac tissue in mice with diabetes induced either genetically or by high-fat diet (HFD). FoxO activity was critically linked with development of cardiomyopathy: cardiomyocyte-specific deletion of FoxO1 rescued HFD-induced declines in cardiac function and preserved cardiomyocyte insulin responsiveness. FoxO1-depleted cells displayed a shift in their metabolic substrate usage, from free fatty acids to glucose, associated with decreased accumulation of lipids in the heart. Furthermore, we found that FoxO1-dependent downregulation of IRS1 resulted in blunted Akt signaling and insulin resistance. Together, these data suggest that activation of FoxO1 is an important mediator of diabetic cardiomyopathy and is a promising therapeutic target for the disease. PMID:22326951

  4. Therapeutic Benefit of Extended Thymosin ?4 Treatment Is Independent of Blood Glucose Level in Mice with Diabetic Peripheral Neuropathy

    PubMed Central

    Wang, Lei; Chopp, Michael; Jia, Longfei; Lu, Xuerong; Szalad, Alexandra; Zhang, Yi; Zhang, RuiLan; Zhang, Zheng Gang

    2015-01-01

    Peripheral neuropathy is a chronic complication of diabetes mellitus. To investigated the efficacy and safety of the extended treatment of diabetic peripheral neuropathy with thymosin ?4 (T?4), male diabetic mice (db/db) at the age of 24 weeks were treated with T?4 or saline for 16 consecutive weeks. Treatment of diabetic mice with T?4 significantly improved motor (MCV) and sensory (SCV) conduction velocity in the sciatic nerve and the thermal and mechanical latency. However, T?4 treatment did not significantly alter blood glucose levels. Treatment with T?4 significantly increased intraepidermal nerve fiber density. Furthermore, T?4 counteracted the diabetes-induced axon diameter and myelin thickness reductions and the g-ratio increase in sciatic nerve. In vitro, compared with dorsal root ganglia (DRG) neurons derived from nondiabetic mice, DRG neurons derived from diabetic mice exhibited significantly decreased neurite outgrowth, whereas T?4 promoted neurite growth in these diabetic DRG neurons. Blockage of the Ang1/Tie2 signaling pathway with a neutralized antibody against Tie2 abolished T?4-increased neurite outgrowth. Our data demonstrate that extended T?4 treatment ameliorates diabetic-induced axonal degeneration and demyelination, which likely contribute to therapeutic effect of T?4 on diabetic neuropathy. The Ang1/Tie2 pathway may mediate T?4-induced axonal remodeling. PMID:25945352

  5. Heparanase Is Essential for the Development of Diabetic Nephropathy in Mice

    PubMed Central

    Gil, Natali; Goldberg, Rachel; Neuman, Tzahi; Garsen, Marjolein; Zcharia, Eyal; Rubinstein, Ariel M.; van Kuppevelt, Toin; Meirovitz, Amichay; Pisano, Claudio; Li, Jin-Ping; van der Vlag, Johan; Vlodavsky, Israel; Elkin, Michael

    2012-01-01

    Diabetic nephropathy (DN) is the major life-threatening complication of diabetes. Abnormal permselectivity of glomerular basement membrane (GBM) plays an important role in DN pathogenesis. Heparanase is the predominant enzyme that degrades heparan sulfate (HS), the main polysaccharide of the GBM. Loss of GBM HS in diabetic kidney was associated with increased glomerular expression of heparanase; however, the causal involvement of heparanase in the pathogenesis of DN has not been demonstrated. We report for the first time the essential involvement of heparanase in DN. With the use of Hpse-KO mice, we found that deletion of the heparanase gene protects diabetic mice from DN. Furthermore, by investigating the molecular mechanism underlying induction of the enzyme in DN, we found that transcription factor early growth response 1 (Egr1) is responsible for activation of heparanase promoter under diabetic conditions. The specific heparanase inhibitor SST0001 markedly decreased the extent of albuminuria and renal damage in mouse models of DN. Our results collectively underscore the crucial role of heparanase in the pathogenesis of DN and its potential as a highly relevant target for therapeutic interventions in patients with DN. PMID:22106160

  6. Methadone ameliorates multiple-low-dose streptozotocin-induced type 1 diabetes in mice

    SciTech Connect

    Amirshahrokhi, K.; Dehpour, A.R.; Hadjati, J.; Sotoudeh, M.; Ghazi-Khansari, M.

    2008-10-01

    Type 1 diabetes is an autoimmune disease characterized by inflammation of pancreatic islets and destruction of {beta} cells by the immune system. Opioids have been shown to modulate a number of immune functions, including T helper 1 (Th1) and T helper 2 (Th2) cytokines. The immunosuppressive effect of long-term administration of opioids has been demonstrated both in animal models and humans. The aim of this study was to determine the effect of methadone, a {mu}-opioid receptor agonist, on type 1 diabetes. Administration of multiple low doses of streptozotocin (STZ) (MLDS) (40mg/kg intraperitoneally for 5 consecutive days) to mice resulted in autoimmune diabetes. Mice were treated with methadone (10mg/kg/day subcutaneously) for 24days. Blood glucose, insulin and pancreatic cytokine levels were measured. Chronic methadone treatment significantly reduced hyperglycemia and incidence of diabetes, and restored pancreatic insulin secretion in the MLDS model. The protective effect of methadone can be overcome by pretreatment with naltrexone, an opioid receptor antagonist. Also, methadone treatment decreased the proinflammatory Th1 cytokines [interleukin (IL)-1{beta}, tumor necrosis factor-{alpha} and interferon-{gamma}] and increased anti-inflammatory Th2 cytokines (IL-4 and IL-10). Histopathological observations indicated that STZ-mediated destruction of {beta} cells was attenuated by methadone treatment. It seems that methadone as an opioid agonist may have a protective effect against destruction of {beta} cells and insulitis in the MLDS model of type 1 diabetes.

  7. Sildenafil Ameliorates Long Term Peripheral Neuropathy in Type II Diabetic Mice

    PubMed Central

    Wang, Lei; Chopp, Michael; Szalad, Alexandra; Jia, LongFei; Lu, XueRong; Lu, Mei; Zhang, Li; Zhang, Yi; Zhang, RuiLan; Zhang, Zheng Gang

    2015-01-01

    Diabetic peripheral neuropathy is a common complication of long-standing diabetes mellitus. To mimic clinical trials in which patients with diabetes enrolled have advanced peripheral neuropathy, we investigated the effect of sildenafil, a specific inhibitor of phosphodiesterase type 5 enzyme, on long term peripheral neuropathy in middle aged male mice with type II diabetes. Treatment of diabetic mice (BKS.Cg-m+/+Leprdb/J, db/db) at age 36 weeks with sildenafil significantly increased functional blood vessels and regional blood flow in the sciatic nerve, concurrently with augmentation of intra-epidermal nerve fiber density in the skin and myelinated axons in the sciatic nerve. Functional analysis showed that the sildenafil treatment considerably improved motor and sensory conduction velocities in the sciatic nerve and peripheral thermal stimulus sensitivity compared with the saline treatment. In vitro studies showed that mouse dermal endothelial cells (MDE) cultured under high glucose levels exhibited significant down regulation of angiopoietin 1 (Ang1) expression and reduction of capillary-like tube formation, which were completely reversed by sildenafil. In addition, incubation of dorsal root ganglia (DRG) neurons with conditioned medium harvested from MDE under high glucose levels suppressed neurite outgrowth, where as conditional medium harvested from MDE treated with sildenafil under high glucose levels did not inhibit neurite outgrowth of DRG neurons. Moreover, blockage of the Ang1 receptor, Tie2, with a neutralized antibody against Tie2 abolished the beneficial effect of sildenafil on tube formation and neurite outgrowth. Collectively, our data indicate that sildenafil has a therapeutic effect on long term peripheral neuropathy of middle aged diabetic mice and that improvement of neurovascular dysfunction by sildenafil likely contributes to the amelioration of nerve function. The Ang1/Tie2 signaling pathway may play an important role in these restorative processes. PMID:25689401

  8. Proregenerative Microenvironment Triggered by Donor Mesenchymal Stem Cells Preserves Renal Function and Structure in Mice with Severe Diabetes Mellitus

    PubMed Central

    Ezquer, Fernando; Giraud-Billoud, Maximiliano; Carpio, Daniel; Cabezas, Fabián; Conget, Paulette; Ezquer, Marcelo

    2015-01-01

    The aim of our work was to evaluate, in an animal model of severe diabetes mellitus, the effect of mesenchymal stem cells (MSCs) administration on diabetic nephropathy (DN) progression. After diabetes induction, one group of mice received the vehicle (DM) and other group received a single dose of MSCs (DM + MSCs). DM + MSCs mice showed a significant improvement in functional parameters of the kidney compared with untreated mice. While DM mice presented marked histopathological changes characteristics of advanced stages of DN (fibrosis, glomerulosclerosis, glomerular basement membrane thickening, capillary occlusion, decreased podocyte density, and effacement of foot processes), DM + MSCs mice showed only slight tubular dilatation. The renoprotection was not associated with an improvement in diabetic condition and very low number of donor cells was found in the kidney of DM + MSCs mice, suggesting that renoprotection could be mediated by paracrine effects. Indeed, DM + MSC mice presented increased renal proliferation index, decreased renal apoptotic index and the restoration of proregenerative factors, and anti-inflammatory cytokines levels. Moreover, macrophage infiltration and oxidative stress damage were also reduced in DM + MSCs mice. Our data demonstrate that MSC administration triggers a proregenerative microenvironment in DN kidney, which allows the preservation of the renal function even if diabetes was uncorrected. PMID:26167475

  9. Proregenerative Microenvironment Triggered by Donor Mesenchymal Stem Cells Preserves Renal Function and Structure in Mice with Severe Diabetes Mellitus.

    PubMed

    Ezquer, Fernando; Giraud-Billoud, Maximiliano; Carpio, Daniel; Cabezas, Fabián; Conget, Paulette; Ezquer, Marcelo

    2015-01-01

    The aim of our work was to evaluate, in an animal model of severe diabetes mellitus, the effect of mesenchymal stem cells (MSCs) administration on diabetic nephropathy (DN) progression. After diabetes induction, one group of mice received the vehicle (DM) and other group received a single dose of MSCs (DM + MSCs). DM + MSCs mice showed a significant improvement in functional parameters of the kidney compared with untreated mice. While DM mice presented marked histopathological changes characteristics of advanced stages of DN (fibrosis, glomerulosclerosis, glomerular basement membrane thickening, capillary occlusion, decreased podocyte density, and effacement of foot processes), DM + MSCs mice showed only slight tubular dilatation. The renoprotection was not associated with an improvement in diabetic condition and very low number of donor cells was found in the kidney of DM + MSCs mice, suggesting that renoprotection could be mediated by paracrine effects. Indeed, DM + MSC mice presented increased renal proliferation index, decreased renal apoptotic index and the restoration of proregenerative factors, and anti-inflammatory cytokines levels. Moreover, macrophage infiltration and oxidative stress damage were also reduced in DM + MSCs mice. Our data demonstrate that MSC administration triggers a proregenerative microenvironment in DN kidney, which allows the preservation of the renal function even if diabetes was uncorrected. PMID:26167475

  10. Improvement of diabetes, obesity and hypertension in type 2 diabetic KKA{sup y} mice by bis(allixinato)oxovanadium(IV) complex

    SciTech Connect

    Adachi, Yusuke; Yoshikawa, Yutaka; Yoshida, Jiro; Kodera, Yukihiro . E-mail: kodera_y@wakunaga.co.jp; Katoh, Akira . E-mail: katoh@st.seikei.ac.jp; Takada, Jitsuya . E-mail: takada@hl.rri.kyoto-u.ac.jp; Sakurai, Hiromu . E-mail: sakurai@mb.kyoto-phu.ac.jp

    2006-07-07

    Previously, we found that bis(allixinato)oxovanadium(IV) (VO(alx){sub 2}) exhibits a potent hypoglycemic activity in type 1-like diabetic mice. Since the enhancement of insulin sensitivity is involved in one of the mechanisms by which vanadium exerts its anti-diabetic effects, VO(alx){sub 2} was further tested in type 2 diabetes with low insulin sensitivity. The effect of oral administration of VO(alx){sub 2} was examined in obesity-linked type 2 diabetic KKA{sup y} mice. Treatment of VO(alx){sub 2} for 4 weeks normalized hyperglycemia, glucose intolerance, hyperinsulinemia, hypercholesterolemia and hypertension in KKA{sup y} mice; however, it had no effect on hypoadiponectinemia. VO(alx){sub 2} also improved hyperleptinemia, following attenuation of obesity in KKA{sup y} mice. This is the first example in which a vanadium compound improved leptin resistance in type 2 diabetes by oral administration. On the basis of these results, VO(alx){sub 2} is proposed to enhance not only insulin sensitivity but also leptin sensitivity, which in turn improves diabetes, obesity and hypertension in an obesity-linked type 2 diabetic animal.

  11. Contribution of neural cell death to depressive phenotypes of streptozotocin-induced diabetic mice.

    PubMed

    Chen, Cheng; Wang, Yun; Zhang, Juan; Ma, Lian; Gu, Jiang; Ho, Guyu

    2014-06-01

    Major depression disorder (MDD) or depression is highly prevalent in individuals with diabetes, and the depressive symptoms are more severe and less responsive to antidepressant therapies in these patients. The underlying mechanism is little understood. We hypothesized that the pathophysiology of comorbid depression was more complex than that proposed for MDD and that neural cell death played a role in the disease severity. To test this hypothesis, we generated streptozotocin (STZ)-induced diabetic mice. These mice had blood glucose levels threefold above controls and exhibited depressive phenotypes as judged by a battery of behavioral tests, thus confirming the comorbidity in mice. Immunohistological studies showed markedly increased TUNEL-positive cells in the frontal cortex and hippocampus of the comorbid mice, indicating apoptosis. This finding was supported by increased caspase-3 and decreased Bcl-2 proteins in these brain regions. In addition, the serum brain-derived neurotrophic factor (BDNF) level of comorbid mice was reduced compared with controls, further supporting the neurodegenerative change. Mechanistic analyses showed an increased expression of mitochondrial fission genes fission protein 1 (Fis1) and dynamin-related protein 1 (Drp1), and a decreased expression of mitochondrial fusion genes mitofusin 1 (Mfn1), mitofusin 2 (Mfn2) and optical atrophy 1 (Opa1). Representative assessment of the proteins Drp1 and Mfn2 mirrored the mRNA changes. The data demonstrated that neural cell death was associated with the depressive phenotype of comorbid mice and that a fission-dominant expression of genes and proteins mediating mitochondrial dynamics played a role in the hyperglycemia-induced cell death. The study provides new insight into the disease mechanism and could aid the development of novel therapeutics aimed at providing neuroprotection by modulating mitochondrial dynamics to treat comorbid depression with diabetes. PMID:24764190

  12. An aqueous extract of Portulaca oleracea ameliorates diabetic nephropathy through suppression of renal fibrosis and inflammation in diabetic db/db mice.

    PubMed

    Lee, An Sook; Lee, Yun Jung; Lee, So Min; Yoon, Jung Joo; Kim, Jin Sook; Kang, Dae Gill; Lee, Ho Sub

    2012-01-01

    Diabetic nephropathy is one of the most common microvascular complications of diabetes and the leading cause of end-stage renal disease. In the present study, we investigated the renoprotective effect of the aqueous extract of Portulaca oleracea (AP) on diabetic nephropathy accelerated by renal fibrosis and inflammation in type 2 diabetic db/db mice. The mice were treated with AP (300 mg/kg/day, p.o.) for ten weeks to examine the long-term effects on diabetic nephropathy and renal dysfunction. We found that AP treatment markedly lowered blood glucose to 412 ± 11.4 mg/dl and plasma creatinine level to 2.3 ± 0.8 mg/dl compared to db/db mice (p < 0.05, p < 0.01, respectively). This study also showed that treatment with AP significantly decreased water intake and urine volume in diabetic db/db mice (p < 0.05). In immunohistological study, the renal expression of transforming growth factor-?1 (TGF-?1), advanced glycation end products (AGE), and intercellular adhesion molecule (ICAM)-1 markedly increased in the renal cortex of untreated db/db mice (p < 0.01). In contrast, AP treatment significantly reduced these expressions to 50 ± 2.1%, 48 ± 2.8%, 61 ± 1.1%, respectively (p < 0.01). Furthermore, NF-?B p65 activation in renal tissues markedly increased in untreated db/db mice, which was significantly suppressed by AP treatment. Taken together, these findings suggest that AP attenuates diabetic nephropathy through inhibition of renal fibrosis and inflammation in db/db mice. PMID:22745066

  13. Neurotensin-loaded collagen dressings reduce inflammation and improve wound healing in diabetic mice.

    PubMed

    Moura, Liane I F; Dias, Ana M A; Suesca, Edward; Casadiegos, Sergio; Leal, Ermelindo C; Fontanilla, Marta R; Carvalho, Lina; de Sousa, Hermínio C; Carvalho, Eugénia

    2014-01-01

    Impaired wound healing is an important clinical problem in diabetes mellitus and results in failure to completely heal diabetic foot ulcers (DFUs), which may lead to lower extremity amputations. In the present study, collagen based dressings were prepared to be applied as support for the delivery of neurotensin (NT), a neuropeptide that acts as an inflammatory modulator in wound healing. The performance of NT alone and NT-loaded collagen matrices to treat wounds in streptozotocin (STZ) diabetic induced mice was evaluated. Results showed that the prepared dressings were not-cytotoxic up to 72h after contact with macrophages (Raw 264.7) and human keratinocyte (HaCaT) cell lines. Moreover, those cells were shown to adhere to the collagen matrices without noticeable change in their morphology. NT-loaded collagen dressings induced faster healing (17% wound area reduction) in the early phases of wound healing in diabetic wounded mice. In addition, they also significantly reduced inflammatory cytokine expression namely, TNF-? (p<0.01) and IL-1? (p<0.01) and decreased the inflammatory infiltrate at day 3 post-wounding (inflammatory phase). After complete healing, metalloproteinase 9 (MMP-9) is reduced in diabetic skin (p<0.05) which significantly increased fibroblast migration and collagen (collagen type I, alpha 2 (COL1A2) and collagen type III, alpha 1 (COL3A1)) expression and deposition. These results suggest that collagen-based dressings can be an effective support for NT release into diabetic wound enhancing the healing process. Nevertheless, a more prominent scar is observed in diabetic wounds treated with collagen when compared to the treatment with NT alone. PMID:24161538

  14. Nasal administration of CTB-insulin induces active tolerance against autoimmune diabetes in non-obese diabetic (NOD) mice

    PubMed Central

    Aspord, C; Thivolet, C

    2002-01-01

    Nasal administration of beta cell-derived auto-antigens has been reported to suppress the development of autoimmune diabetes. We investigated the tolerogenic effects of insulin conjugated to the B subunit of cholera toxin (CTB). Nasal administration of 1 µg of CTB-insulin significantly delayed the incidence of diabetes in comparison to CTB treated mice. However, administration of 4 or 8 µg of the conjugate had no protective effect. Protection induced by CTB-insulin was transferred to naive recipients by splenic CD4+ T cells. This result favours an active cellular mechanism of regulation, which was lost using higher (4–8 µg) or lower (0·1–0·5 µg) amounts of the conjugate. When co-administered with diabetogenic T cells, splenic T cells from CTB-insulin-treated mice reduced the lymphocytic infiltration of the islets. Reverse transcription-polymerase chain reaction analysis of recipients’ pancreatic glands revealed an increase of TGF-? and IL-10 transcripts after donor mice tolerization, while levels of IFN-? and IL-4 RNAs were unchanged. We observed a significant increase of T cell proliferation after unspecific stimulation in the spleen and pancreatic lymph nodes 24 h after CTB-insulin administration in comparison to control treatment. Higher amounts of IL-4 and IFN-? were noticed in pancreatic lymph nodes of tolerized mice upon in vitro stimulation. Antigen-specific unresponsiveness after immunization and upon subsequent in vitro exposure to homologous antigen was obtained in nasally treated animals. Our results underlined the importance of nasal mucosa as an inducing site of tolerance and provided evidence for similar mechanisms of action to what has been described for the oral route, which favoured a CTB-insulin specific effect. PMID:12390307

  15. Effect of C-peptide Alone or in Combination with Nicotinamide on Glucose and Insulin Levels in Streptozotocin–Nicotinamide-Induced Type 2 Diabetic Mice

    PubMed Central

    AHANGARPOUR, Akram; RAMEZANI ALI AKBARI, Fatemeh; FATHI MOGHADAM, Hadi

    2014-01-01

    Background: Both C-peptide and nicotinamide are known to reduce blood glucose in type 1 diabetes. In the present study, the effects of C-peptide alone or in combination with nicotinamide on glucose and insulin levels in streptozotocin-nicotinamide-induced type 2 diabetic mice. Methods: The study used 70 adult male NMARI mice, weighing 25–35 g, divided into seven groups: control; type 1 diabetic; type 2 diabetic; type 2 diabetic + C-peptide; type 2 diabetic + nicotinamide; type 2 diabetic + nicotinamide and C-peptide; type 2 diabetic + glyburide. Type 2 diabetes was induced with ip injection of streptozotocin–nicotinamide. Twenty eight days after the onset of diabetes, treatment with C-peptide, nicotinamide, nicotinamide + C-peptide, or glyburide were initiated. Glucose and insulin levels were evaluated. One-way ANOVA and Least Significant Difference (LSD) tests were used to test for significance. Results: Blood glucose significantly increased (P < 0.001) in all diabetic mice compared with control mice. Insulin resistance and blood glucose levels were significantly reduced (P < 0.05) in C-peptide and nicotinamide + C-peptide mice compared with type 2 diabetic mice. Conclusion: The present study supports the anti-diabetic effects of C-peptide, nicotinamide + C-peptide, and suggests that one of the anti-diabetic mechanisms of these compounds is mediated through the reduction of insulin resistance. PMID:25977616

  16. Diabetes

    MedlinePLUS

    ... version of this page please turn Javascript on. Diabetes What is Diabetes? Too Much Glucose in the Blood Diabetes means ... high, causing pre-diabetes or diabetes. Types of Diabetes There are three main kinds of diabetes: type ...

  17. Evaluation of Anticonvulsive Effect of Magnesium Oxide Nanoparticles in Comparison with Conventional MgO in Diabetic and Non-diabetic Male Mice

    PubMed Central

    Jahangiri, Leila; Kesmati, Mahnaz; Najafzadeh, H.

    2014-01-01

    Introduction Some studies showed that magnesium has anticonvulsive effect in some animal models. Despite of the availability of well-studied anticonvulsant drugs, this evaluation was not carried on new kind of magnesium supplement, magnesium oxide nanoparticles (nMgO). According to the association between magnesium and convulsion and high prevalence of seizure and epilepsy in diabetics, this study was designed to evaluate the effect of nMgO compared to conventional MgO (cMgO) on strychnine-induced convulsion model in diabetic and non-diabetic mice. Methods Healthy male albino mice were divided into 10 groups. Diabetes mellitus was induced by streptozotocin in 5 groups. Conventional and nanoparticle MgO (5 and 10mg/kg) were administered to diabetic and non-diabetic mice, then strychnine were injected and onset of convulsions and time of death measured after strychnine administration. Results There were no significant differences between normal and diabetic groups in onset of convulsions and time of death. Pretreatment of cMgO did not have anticonvulsant effect in strychnine-induced convulsion in normal and diabetic mice. But nMgO significantly changed convulsion onset and death time after strychnine administration in normal and diabetic status (p < 0.05). Discussion According to our results, it seems that acute administration of nMgO may be important in prevention of convulsion and is more effective than its conventional form in showing anticonvulsive effect that probably is related to the physicochemical properties of nMgO, especially in diabetic subjects, a point that need further investigations. PMID:25337374

  18. Immunomodulatory and Antidiabetic Effects of a New Herbal Preparation (HemoHIM) on Streptozotocin-Induced Diabetic Mice

    PubMed Central

    Kim, Jong-Jin; Choi, Jina; Lee, Mi-Kyung; Kang, Kyung-Yun; Paik, Man-Jeong; Jo, Sung-Kee; Jung, Uhee; Park, Hae-Ran; Yee, Sung-Tae

    2014-01-01

    HemoHIM (a new herbal preparation of three edible herbs: Angelica gigas Nakai, Cnidium officinale Makino, and Paeonia japonica Miyabe) was developed to protect immune, hematopoietic, and self-renewal tissues against radiation. This study determined whether or not HemoHIM could alter hyperglycemia and the immune response in diabetic mice. Both nondiabetic and diabetic mice were orally administered HemoHIM (100?mg/kg) once a day for 4 weeks. Diabetes was induced by single injection of streptozotocin (STZ, 200?mg/kg, i.p.). In diabetic mice, HemoHIM effectively improved hyperglycemia and glucose tolerance compared to the diabetic control group as well as elevated plasma insulin levels with preservation of insulin staining in pancreatic ?-cells. HemoHIM treatment restored thymus weight, white blood cells, lymphocyte numbers, and splenic lymphocyte populations (CD4+ T and CD8+ T), which were reduced in diabetic mice, as well as IFN-? production in response to Con A stimulation. These results indicate that HemoHIM may have potential as a glucose-lowering and immunomodulatory agent by enhancing the immune function of pancreatic ?-cells in STZ-induced diabetic mice. PMID:25045390

  19. Rosiglitazone treatment reversed depression- but not psychosis-like behavior of db/db diabetic mice.

    PubMed

    Sharma, Ajaykumar N; Elased, Khalid M; Lucot, James B

    2012-05-01

    The objective of the present study was to examine the effect of long-term management of insulin resistance and hyperglycemia on neurobehavioral deficits in db/db mice. In this study, 5-week-old db/db and lean control mice were fed with rosiglitazone (20 mg/kg/day) mixed or standard chow for a duration of 5 weeks. Mice were monitored weekly for blood glucose concentration. Five weeks after the onset of treatment, they were subjected to the forced swim test (FST), pre-pulse inhibition (PPI), open field test (OFT) and fear-potentiated startle (FPS) test to examine for depression, psychosis-like behavior, locomotor activity and emotional learning, respectively. Rosiglitazone normalized hyperglycemia and improved glucose tolerance. Rosiglitazone significantly reduced immobility time in the FST in db/db mice, suggesting an antidepressant-like effect. However, rosiglitazone failed to reverse disruption of PPI in db/db mice, indicating its ineffectiveness against psychosis-like behavior. In the OFT, rosiglitazone did not affect the activity of db/db mice, suggesting its antidepressant-like effect was independent of changes in locomotor activity. In the FPS test, db/db mice showed impaired emotional learning and rosiglitazone failed to correct it. In conclusion, long-term blood glucose management in type-2 diabetics may help to limit the co-occurrence of depression but not the psychotic symptoms and ability to cope with stress. PMID:22331176

  20. Bis(quercetinato)oxovanadium IV Reverses Metabolic Changes in Streptozotocin-Induced Diabetic Mice.

    PubMed

    Shukla, Ruchi; Padhye, Subhash; Modak, Manisha; Ghaskadbi, Saroj S; Bhonde, Ramesh R

    2007-01-01

    Organic vanadium compounds offer several advantages in the treatment of diabetes, yet they are impractical to use because of known side effects. In order to ameliorate the side effects of vanadium, we conjugated it with quercetin to form bis(quercetinato)oxovanadium IV (BQOV). This study evaluates the effect of BQOV treatment on carbohydrate metabolism and overall oxidative stress in streptozotocin-induced (STZ) diabetic mice. Administration of BQOV orally to diabetic mice for 3 weeks led to a reduction of blood glucose levels and the animals exhibited normal glucose tolerance at the end of the study period. The increase in glucose uptake by skeletal muscle and liver as well as the normalization of mRNA levels of G-6-Pase and glucokinase in the liver after BQOV treatment pointed to improvements in carbohydrate metabolism. The analysis of the antioxidant status of serum, liver and pancreas revealed reduced oxidative stress in BQOV-treated animals compared to untreated diabetic controls. Serum analyses for kidney and liver function showed that BQOV treatment provoked total protection of the kidney and partial protection of the liver from diabetogenic insults. The number of insulin-positive cells and the amount of pancreatic insulin in treated mice (1.2038 +/- 0.34 ng/mg tissue) did not account for pancreatic regeneration but suggested an insulin-mimetic action on the part of BQOV. Moreover, administration of BQOV for 3 weeks did not show any visible side-effects. This data indicate that BQOV is a safe and potent agent for diabetes treatment, because it is able to improve carbohydrate metabolism and to reduce overall oxidative stress. PMID:17565414

  1. Bis(quercetinato)oxovanadium IV Reverses Metabolic Changes in Streptozotocin-Induced Diabetic Mice

    PubMed Central

    Shukla, Ruchi; Padhye, Subhash; Modak, Manisha; Ghaskadbi, Saroj S.; Bhonde, Ramesh R.

    2007-01-01

    Organic vanadium compounds offer several advantages in the treatment of diabetes, yet they are impractical to use because of known side effects. In order to ameliorate the side effects of vanadium, we conjugated it with quercetin to form bis(quercetinato)oxovanadium IV (BQOV). This study evaluates the effect of BQOV treatment on carbohydrate metabolism and overall oxidative stress in streptozotocin-induced (STZ) diabetic mice. Administration of BQOV orally to diabetic mice for 3 weeks led to a reduction of blood glucose levels and the animals exhibited normal glucose tolerance at the end of the study period. The increase in glucose uptake by skeletal muscle and liver as well as the normalization of mRNA levels of G-6-Pase and glucokinase in the liver after BQOV treatment pointed to improvements in carbohydrate metabolism. The analysis of the antioxidant status of serum, liver and pancreas revealed reduced oxidative stress in BQOV-treated animals compared to untreated diabetic controls. Serum analyses for kidney and liver function showed that BQOV treatment provoked total protection of the kidney and partial protection of the liver from diabetogenic insults. The number of insulin-positive cells and the amount of pancreatic insulin in treated mice (1.2038 ± 0.34 ng/mg tissue) did not account for pancreatic regeneration but suggested an insulin-mimetic action on the part of BQOV. Moreover, administration of BQOV for 3 weeks did not show any visible side-effects. This data indicate that BQOV is a safe and potent agent for diabetes treatment, because it is able to improve carbohydrate metabolism and to reduce overall oxidative stress. PMID:17565414

  2. Effects of dietary fucoxanthin on cholesterol metabolism in diabetic/obese KK-Ay mice

    PubMed Central

    2012-01-01

    Background Fucoxanthin is a xanthophyll present in brown seaweeds and has several beneficial effects, including anti-obesity and anti-diabetic effects. However, we and another group previously observed that fucoxanthin increases serum cholesterol levels in rodents. Cholesterol is an important component of cell membranes and biosynthesis of bile acids. Serum cholesterol levels are also closely associated with atherosclerosis. Therefore, we sought to identify the mechanism underlying the increase in serum cholesterol levels by fucoxanthin. Methods Diabetic/obese KK-Ay mice were fed a diet containing 0.2% fucoxanthin for 4?weeks. The mice were sacrificed, and total blood samples were collected for the measurement of serum total cholesterol, HDL-cholesterol and non-HDL-cholesterol levels. Cholesterol content in tissues was also analyzed. Real-time PCR and Western blotting were performed to determine hepatic mRNA and protein expression of genes involved in cholesterol metabolism, respectively. Results Dietary fucoxanthin significantly increased serum HDL and non-HDL cholesterol levels, and reduced hepatic cholesterol content. In liver, the expression of SREBP1, SREBP2 and their target genes involved in cholesterol biosynthesis significantly increased and tended to increase in the fucoxanthin-fed mice, respectively. In contrast, hepatic levels of LDLR and SR-B1 proteins which is important factors for LDL-cholesterol and HDL-cholesterol uptake in the liver from serum, decreased to 60% and 80% in the fucoxanthin-fed mice, respectively, compared with the control mice. Further, we found that dietary fucoxanthin significantly increased the mRNA expression of proprotein convertase subtilisin/kexin type 9 (PCSK9), which enhances intracellular degradation of LDLR in lysosomes. Conclusions Fucoxanthin increased HDL-cholesterol and non-HDL-cholesterol levels in KK-Ay mice by inducing SREBP expression and reduced cholesterol uptake in the liver via down-regulation of LDLR and SR-B1, resulted in increased serum cholesterol in the mice. PMID:22962999

  3. Recovery from diabetes in neonatal mice after a low-dose streptozotocin treatment

    SciTech Connect

    Kataoka, Masateru; Kawamuro, Yuki; Shiraki, Nobuaki; Miki, Rika; Sakano, Daisuke; The Global COE Cell Fate Regulation Research and Education Unit, Kumamoto University, Honjo 2-2-1, Chuo-ku, Kumamoto 860-0811 ; Yoshida, Tetsu; Yasukawa, Takanori; Kume, Kazuhiko; Kume, Shoen; The Global COE Cell Fate Regulation Research and Education Unit, Kumamoto University, Honjo 2-2-1, Chuo-ku, Kumamoto 860-0811

    2013-01-18

    Highlights: ? We monitored long-term beta cell regeneration in neonatal mice treated with low dose STZ. ? Low-dose STZ neonatal female mice recovered blood glucose in 150 days. ? Glucose intolerance of the STZ treated mice significantly improved in 150 days. -- Abstract: Administration of streptozotocin (STZ) induces destruction of ?-cells and is widely used as an experimental animal model of type I diabetes. In neonatal rat, after low-doses of STZ-mediated destruction of ?-cells, ?-cells regeneration occurs and reversal of hyperglycemia was observed. However, in neonatal mice, ?-cell regeneration seems to occur much slowly compared to that observed in the rat. Here, we described the time dependent quantitative changes in ?-cell mass during a spontaneous slow recovery of diabetes induced in a low-dose STZ mice model. We then investigated the underlying mechanisms and analyzed the cell source for the recovery of ?-cells. We showed here that postnatal day 7 (P7) female mice treated with 50 mg/kg STZ underwent the destruction of a large proportion of ?-cells and developed hyperglycemia. The blood glucose increased gradually and reached a peak level at 500 mg/dl on day 35–50. This was followed by a spontaneous regeneration of ?-cells. A reversal of non-fasting blood glucose to the control value was observed within 150 days. However, the mice still showed impaired glucose tolerance on day 150 and day 220, although a significant improvement was observed on day 150. Quantification of the ?-cell mass revealed that the ?-cell mass increased significantly between day 100 and day 150. On day 150 and day 220, the ?-cell mass was approximately 23% and 48.5% of the control, respectively. Of the insulin-positive cells, 10% turned out to be PCNA-positive proliferating cells. Our results demonstrated that, ?-cell duplication is one of the cell sources for ?-cell regeneration.

  4. Differentiation of pancreatic stem and progenitor ?-cells into insulin secreting cells in mice with diabetes mellitus.

    PubMed

    Skurikhin, E G; Ermakova, N N; Khmelevskaya, E S; Pershina, O V; Krupin, V A; Ermolaeva, L A; Dygai, A M

    2014-04-01

    We studied in vitro differentiation of pancreatic stem and progenitor cells into insulin secreting cells in the model of streptozotocin-induced diabetes in C57Bl/6 mice. Streptozotocin was shown to increase the population of pancreatic oligopotent ?-cell precursors (CD45(-), TER119(-), CD133(+), and CD49f(low)) and did not affect multipotent (stem) progenitor cells (CD45(-), TER119(-), CD17(-), CD309(-)). During long-term culturing, diabetic multipotent progenitor cells showed high capacity for self-renewal. A population of dithizone-positive (insulin secreting cells) mononuclear cells was obtained releasing insulin after prolonged culturing in suspension enriched with diabetic CD45(-), TER119(-), CD17(-), and CD309(-) cells. The rate of generation of "new" insulin-producing cells and insulin release in the samples of experimental group considerably exceeded activity of the corresponding processes in the control group. PMID:24824681

  5. Immune responses to an encapsulated allogeneic islet {beta}-cell line in diabetic NOD mice

    SciTech Connect

    Black, Sasha P. . E-mail: Sasha.Black@ca.crl.com; Constantinidis, Ioannis; Cui, Hong; Tucker-Burden, Carol; Weber, Collin J.; Safley, Susan A.

    2006-02-03

    Our goal is to develop effective islet grafts for treating type 1 diabetes. Since human islets are scarce, we evaluated the efficacy of a microencapsulated insulin-secreting conditionally transformed allogeneic {beta}-cell line ({beta}TC-tet) in non-obese diabetic mice treated with tetracycline to inhibit cell growth. Relatively low serum levels of tetracycline controlled proliferation of {beta}TC-tet cells without inhibiting effective control of hyperglycemia in recipients. There was no significant host cellular reaction to the allografts or host cell adherence to microcapsules, and host cytokine levels were similar to those of sham-operated controls. We conclude that encapsulated allogeneic {beta}-cell lines may be clinically relevant, because they effectively restore euglycemia and do not elicit a strong cellular immune response following transplantation. To our knowledge, this is First extensive characterization of the kinetics of host cellular and cytokine responses to an encapsulated islet cell line in an animal model of type 1 diabetes.

  6. Hypoglycemic Effect of Padina arborescens Extract in Streptozotocin-induced Diabetic Mice

    PubMed Central

    Park, Mi Hwa; Han, Ji Sook

    2012-01-01

    This study investigated the hypoglycemic effect of the Padina arborescens extract in STZ-induced diabetic mice. Freeze-dried Padina arborescens were extracted with 80% methanol and concentrated for use in this study. The hypoglycemic effect was determined by inhibitory activities against ?-glucosidase and ?-amylase as well as the alleviation of postprandial blood glucose level. Padina arborescens extracts showed higher inhibitory activities than acarbose, a positive control against ?-glucosidase and ?-amylase. The IC50 values of Padina arborescens extracts against ?-glucosidase and ?-amylase were 0.26 and 0.23 mg/mL, respectively, which evidenced as more effective than observed with acarbose. The increase of postprandial blood glucose levels were significantly suppressed in the Padina arborescens extract administered group than the control group in the streptozotocin induced diabetic mice. Furthermore, the area under the curve (AUC) was significantly lowered via Padina arborescens extract administration in diabetic mice (p < 0.05). These results indicated that the Padina arborescens extract might be used as an inhibitor of ?-glucosidase and ?-amylase and delay absorption of dietary carbohydrates. PMID:24471091

  7. Effects of malted barley extract and banaba extract on blood glucose levels in genetically diabetic mice.

    PubMed

    Hong, Heeok; Jai Maeng, Won

    2004-01-01

    This study investigated the therapeutic effects of a malted barley extract (MBE) and of banaba extract on blood glucose, insulin, and other biochemical parameters in genetically diabetic mice (C57BL/KsJ(-) m (+/+) Lepr (db)). The mice were divided into three groups-control, MBE, and banaba-according to supplementation. Both MBE and banaba extracts were orally administered to the animals for 12 weeks at doses of 62.5 mg/kg of body weight and 0.8 mg/kg of body weight, respectively. The body and organ (liver and kidney) weights were not different among groups. Fasting blood glucose was significantly lower in the MBE group compared with the control (P < .05). Hemoglobin A1c content was significantly lower in the MBE group compared with either the control or banaba group (P < .05). There was no significant difference in the serum insulin level among groups. The glucose-6-phosphatase activity in kidney was significantly lower in both the MBE and banaba groups compared with the control group (P < .05), but there was no significant difference between the MBE and banaba groups. Therefore, the results of this study demonstrate that MBE alleviates many of the symptoms of diabetes in genetically obese mice and may offer promise as a therapeutic supplement for the normalization of blood glucose levels in humans with hyperglycemia and have beneficial effects in patients with non-insulin-dependent diabetes mellitus. PMID:15671695

  8. Alleviating Effects of Baechu Kimchi Added Ecklonia cava on Postprandial Hyperglycemia in Diabetic Mice.

    PubMed

    Lee, Hyun-Ah; Song, Yeong-Ok; Jang, Mi-Soon; Han, Ji-Sook

    2013-09-01

    In this study, we investigated the inhibitory effects of Baechu kimchi added Ecklonia cava on the activities of ?-glucosidase and ?-amylase and its alleviating effect on the postprandial hyperglycemia in STZ-induced diabetic mice. Baechu kimchi added Ecklonia cava (BKE, 15%) was fermented at 5°C for 28 days. Optimum ripened BKE was used in this study as it showed the strongest inhibitory activities on ?-glucosidase and ?-amylase by fermentation time among the BKEs in our previous study. The BKE was extracted with 80% methanol and the extract solution was concentrated, and then used in this study. The BKE extract showed higher inhibitory activities than Baechu kimchi extract against ?-glucosidase and ?-amylase. The IC50 values of the BKE extract against ?-glucosidase and ?-amylase were 0.58 and 0.35 mg/mL, respectively; BKE exhibited a lower ?-glucosidase inhibitory activity but a higher ?-amylase inhibitory activity than those of acarbose. The BKE extract alleviated postprandial hyperglycemia caused by starch loading in normal and streptozotocin-induced diabetic mice. Furthermore, the BKE extract significantly lowered the incremental area under the curve in both normal and diabetic mice (P<0.05). These results indicated that the BKE extract may delay carbohydrate digestion and thus glucose absorption. PMID:24471127

  9. Modulation of macrophage inflammatory profile in pregnant nonobese diabetic (NOD) mice.

    PubMed

    Larocca, Luciana; Hauk, Vanesa; Calafat, Mario; Roca, Valeria; Fraccaroli, Laura; Franchi, Ana; Ramhorst, Rosanna; Leirós, Claudia Pérez

    2011-02-20

    During normal early pregnancy circulating monocytes are recruited to the maternal-placental interface where they differentiate to macrophages expressing different functional phenotypes for the maintenance of tissue homeostasis. Pregnancy in the nonobese diabetic (NOD) mouse model presents some pathological features in the pre-diabetic stage. The aim of this work was to analyze the functional profile of peritoneal macrophages faced with inflammatory and phagocytic stimuli in early pregnant pre-diabetic NOD mice and their modulation by vasoactive intestinal peptide (VIP). Pregnant NOD mouse macrophages showed no basal NF?B activation, lower IL-12 and nitrites production compared with the macrophages from non-pregnant NOD mice. Their pro-inflammatory aberrant response to LPS and apoptotic cell challenge was reduced and VIP inhibited macrophage residual deleterious responses to apoptotic cells. A functional phenotype switch in macrophages during pregnancy in NOD mice and a promoting effect of VIP towards this regulatory phenotype would be in line with the central role of macrophages in the maternal-placental dialogue. PMID:21145370

  10. BIM Deficiency Protects NOD Mice From Diabetes by Diverting Thymocytes to Regulatory T Cells.

    PubMed

    Krishnamurthy, Balasubramanian; Chee, Jonathan; Jhala, Gaurang; Trivedi, Prerak; Catterall, Tara; Selck, Claudia; Gurzov, Esteban N; Brodnicki, Thomas C; Graham, Kate L; Wali, Jibran A; Zhan, Yifan; Gray, Daniel; Strasser, Andreas; Allison, Janette; Thomas, Helen E; Kay, Thomas W H

    2015-09-01

    Because regulatory T-cell (Treg) development can be induced by the same agonist self-antigens that induce negative selection, perturbation of apoptosis will affect both negative selection and Treg development. But how the processes of thymocyte deletion versus Treg differentiation bifurcate and their relative importance for tolerance have not been studied in spontaneous organ-specific autoimmune disease. We addressed these questions by removing a critical mediator of thymocyte deletion, BIM, in the NOD mouse model of autoimmune diabetes. Despite substantial defects in the deletion of autoreactive thymocytes, BIM-deficient NOD (NODBim(-/-)) mice developed less insulitis and were protected from diabetes. BIM deficiency did not impair effector T-cell function; however, NODBim(-/-) mice had increased numbers of Tregs, including those specific for proinsulin, in the thymus and peripheral lymphoid tissues. Increased levels of Nur77, CD5, GITR, and phosphorylated I?B-? in thymocytes from NODBim(-/-) mice suggest that autoreactive cells receiving strong T-cell receptor signals that would normally delete them escape apoptosis and are diverted into the Treg pathway. Paradoxically, in the NOD model, reduced thymic deletion ameliorates autoimmune diabetes by increasing Tregs. Thus, modulating apoptosis may be one of the ways to increase antigen-specific Tregs and prevent autoimmune disease. PMID:25948683

  11. Treated of type 1 diabetes mellitus in non-obese diabetic mice by transplantation of allogeneic bone marrow and pancreatic tissue

    SciTech Connect

    Yasumizu, R.; Sugiura, K.; Iwai, H.; Inaba, M.; Makino, S.; Ida, T.; Imura, H.; Hamashima, Y.; Good, R.A.; Ikehara, S.

    1987-09-01

    Non-obese diabetic (NOD) mice provide a model for type 1 diabetes mellitus. We previously showed that allogeneic bone marrow transplantation (ABMT) can prevent and treat insulitis and overt diabetes in NOD mice. However, ABMT alone could not be used to treat overt diabetes in NOD mice whose islets had been completely destroyed. To provide insulin-producing cells, pancreatic tissue from newborn mice was grafted under the renal capsules in combination with ABMT. The aims of concomitant ABMT are as follows. (i) It induces immunological tolerance to the donor-type major histocompatibility complex determinants and permits the host to accept subsequent pancreatic allografts from the bone marrow donor. (ii) ABMT replaces abnormal stem cells with normal stem cells. After transplantation of bone marrow plus newborn pancreas, NOD mice showed reduction of the glycosuria and a normal response in the glucose-tolerance test. Immunohistological study revealed the presence of clustered insulin-containing beta cells in the grafted pancreatic transplants. ABMT may become a viable treatment of established type 1 diabetes mellitus in humans.

  12. A combination hydrogel microparticle-based vaccine prevents type 1 diabetes in non-obese diabetic mice

    PubMed Central

    Yoon, Young Mee; Lewis, Jamal S.; Carstens, Matthew R.; Campbell-Thompson, Martha; Wasserfall, Clive H.; Atkinson, Mark A.; Keselowsky, Benjamin G.

    2015-01-01

    Targeted delivery of self-antigens to the immune system in a mode that stimulates a tolerance-inducing pathway has proven difficult. To address this hurdle, we developed a vaccine based-approach comprised of two synthetic controlled-release biomaterials, poly(lactide-co-glycolide; PLGA) microparticles (MPs) encapsulating denatured insulin (key self-antigen in type 1 diabetes; T1D), and PuraMatrixTM peptide hydrogel containing granulocyte macrophage colony-stimulating factor (GM-CSF) and CpG ODN1826 (CpG), which were included as vaccine adjuvants to recruit and activate immune cells. Although CpG is normally considered pro-inflammatory, it also has anti-inflammatory effects, including enhancing IL-10 production. Three subcutaneous administrations of this hydrogel (GM-CSF/CpG)/insulin-MP vaccine protected 40% of NOD mice from T1D. In contrast, all control mice became diabetic. In vitro studies indicate CpG stimulation increased IL-10 production, as a potential mechanism. Multiple subcutaneous injections of the insulin containing formulation resulted in formation of granulomas, which resolved by 28 weeks. Histological analysis of these granulomas indicated infiltration of a diverse cadre of immune cells, with characteristics reminiscent of a tertiary lymphoid organ, suggesting the creation of a microenvironment to recruit and educate immune cells. These results demonstrate the feasibility of this injectable hydrogel/MP based vaccine system to prevent T1D. PMID:26279095

  13. Protective Effects of Astragaloside IV on db/db Mice with Diabetic Retinopathy

    PubMed Central

    Mao, Pingan; Zhao, Chen; Huang, Qiong; Zhang, Rihua; Fang, Yuan; Song, Qinglu; Yuan, Dongqing; Xie, Ping; Liu, Yun; Liu, Qinghuai

    2014-01-01

    Objectives Diabetic retinopathy (DR) is a common diabetic eye disease which is well-known as the result of microvascular retinal changes. Although the potential biological functions of astragaloside IV (AS IV) have long been described in traditional system of medicine, its protective effect on DR remains unclear. This study aims to investigate the function and mechanism of AS IV on type 2 diabetic db/db mice. Methods Db/db mice were treated with AS IV (4.5 mg/kg or 9 mg/kg) or physiological saline by oral gavage for 20 weeks along with db/m mice. In each group, retinal ganglion cell (RGC) function was measured by pattern electroretinogram (ERG) and apoptosis was determined by Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. Blood and retina aldose reductase (AR) activity were quantified by chemiluminescence analysis. The expressions of phosporylated-ERK1/2, NF-?B were determined by Western blot analysis. Furthermore, the expression of related downstream proteins were quantified by Label-based Mouse Antibody Array. Results Administration of AS IV significantly improved the amplitude in pattern ERG and reduced the apoptosis of RGCs.in db/db mice. Furthermore, downregulation of AR activity, ERK1/2 phosphorylation, NF-?B and related cytokine were observed in AS IV treatment group. Conclusions Our study indicated that AS IV, as an inhibitor of AR, could prevent the activation of ERK1/2 phosporylation and NF-kB and further relieve the RGCs disfunction in db/db mice with DR. It has provided a basis for investigating the clinical efficacy of AR inhibitors in preventing DR. PMID:25411784

  14. Studies on the thymus of non-obese diabetic (NOD) mice: effect of transgene expression.

    PubMed Central

    O'Reilly, L A; Healey, D; Simpson, E; Chandler, P; Lund, T; Ritter, M A; Cooke, A

    1994-01-01

    The non-obese diabetic (NOD) mouse is a good model of insulin-dependent diabetes mellitus. Autoreactive T cells may play a fundamental role in disease initiation in this model, while disregulation of such cells may result from an abnormal thymic microenvironment. Diabetes is prevented in NOD mice by direct introduction of an E alpha d transgene (NOD-E) or a modified I-A beta chain of NOD origin (NOD-PRO or NOD-ASP). To investigate if disease pathology in NOD mice, protection from disease in transgenic NOD-E and NOD-PRO and partial protection from disease in NOD-ASP can be attributed to alterations in the thymic microenvironment, immunohistochemical and flow cytometric analysis of the thymi of these mouse strains was studied. Thymi from NOD and NOD-E mice showed a progressive increase in thymic B-cell percentage from 12 weeks of age. This was accompanied by a concomitant loss in thymic epithelial cells with the appearance of large epithelial-free areas mainly at the corticomedullary junction, which increased in size and number with age and contained the B-cell clusters. Such thymic B cells did not express CD5 and were absent in CBA, NOD-ASP and NOD-PRO mice as were the epithelial cell-free spaces, even at 5 months of age. Therefore the mechanisms of disease protection in the transgenic NOD-E and NOD-ASP/NOD-PRO mice may differ if these thymic abnormalities are related to disease. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:7523287

  15. Oxidative stress contributes to the impaired sonic hedgehog pathway in type 1 diabetic mice with myocardial infarction

    PubMed Central

    XIAO, QING; YANG, YA; ZHAO, XIAO-YA; HE, LI-SHAN; QIN, YUAN; HE, YAN-HUA; ZHANG, GUI-PING; LUO, JIAN-DONG

    2015-01-01

    Our previous study demonstrated that an impaired sonic hedgehog (Shh) pathway contributed to cardiac dysfunction in type 1 diabetic mice with myocardial infarction (MI). The present study aimed to test the hypothesis that oxidative stress may contribute to the impaired Shh pathway and cardiac dysfunction in type 1 diabetic mice with MI. Streptozotocin-induced type 1 diabetic mice (C57/Bl6, male) and rat neonatal cardiomyocytes were used in the present study. Mice were randomly assigned to undergo ligation of the coronary artery or pseudosurgery. A potent antioxidant Tempol was administered in vivo and in vitro. Cardiac function was assessed by echocardiography, capillary density by immunohistochemisty, percentage of myocardial infarct using Massons trichrome staining, reactive oxygen species detection using dihydroethidium dye or 2,7-dichlorofluorescein diacetate probe and protein expression levels of the Shh pathway by western blot analysis. The antioxidant Tempol was shown to significantly increase myocardial protein expression levels of Shh and patched-1 (Ptc1) at 7–18 weeks and improved cardiac function at 18 weeks in type 1 diabetic mice, as compared with mice receiving no drug treatment. Furthermore, myocardial protein expression levels of Shh and Ptc1 were significantly upregulated on day 7 after MI, and capillary density was enhanced. In addition, the percentage area of myocardial infarct was reduced, and the cardiac dysfunction and survival rate were improved on day 21 in diabetic mice treated with Tempol. In vitro, treatment of rat neonatal cardiomyocytes with a mixture of xanthine oxidase and xanthine decreased protein expression levels of Shh and Ptc1 in a concentration-dependent manner, and Tempol attenuated this effect. These results indicate that oxidative stress may contribute to an impaired Shh pathway in type 1 diabetic mice, leading to diminished myocardial healing and cardiac dysfunction. Antioxidative strategies aimed at restoring the endogenous Shh pathway may offer a useful means for improving diabetic cardiac function. PMID:26640546

  16. Hyperbaric oxygen therapy (HBOT) suppresses biomarkers of cell stress and kidney injury in diabetic mice.

    PubMed

    Verma, Rajeev; Chopra, Avijeet; Giardina, Charles; Sabbisetti, Venkata; Smyth, Joan A; Hightower, Lawrence E; Perdrizet, George A

    2015-05-01

    The disease burden from diabetic kidney disease is large and growing. Effective therapies are lacking, despite an urgent need. Hyperbaric oxygen therapy (HBOT) activates Nrf2 and cellular antioxidant defenses; therefore, it may be generally useful for treating conditions that feature chronic oxidative tissue damage. Herein, we determined how periodic exposure to oxygen at elevated pressure affected type 2 diabetes mellitus-related changes in the kidneys of db/db mice. Two groups of db/db mice, designated 2.4 ATA and 1.5 ATA, were treated four times per week with 100 % oxygen at either 1.5 or 2.4 ATA (atmospheres absolute) followed by tests to assess kidney damage and function. The sham group of db/db mice and the Hets group of db/+ mice were handled but did not receive HBOT. Several markers of kidney damage were reduced significantly in the HBOT groups including urinary biomarkers neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C (CyC) along with significantly lower levels of caspase-3 activity in kidney tissue extracts. Other stress biomarkers also showed trends to improvement in the HBOT groups, including urinary albumin levels. Expressions of the stress response genes NRF2, HMOX1, MT1, and HSPA1A were reduced in the HBOT groups at the end of the experiment, consistent with reduced kidney damage in treated mice. Urinary albumin/creatinine ratio (ACR), a measure of albuminuria, was significantly reduced in the db/db mice receiving HBOT. All of the db/db mouse groups had qualitatively similar changes in renal histopathology. Glycogenated nuclei, not previously reported in db/db mice, were observed in these three experimental groups but not in the control group of nondiabetic mice. Overall, our findings are consistent with therapeutic HBOT alleviating stress and damage in the diabetic kidney through cytoprotective responses. These findings support an emerging paradigm in which tissue oxygenation and cellular defenses effectively limit damage from chronic oxidative stress more effectively than chemical antioxidants. PMID:25648080

  17. Long-term but not short-term aspirin treatment attenuates diabetes-associated learning and memory decline in mice.

    PubMed

    Wang, T; Fu, F H; Han, B; Zhang, L M; Zhang, X M

    2011-01-01

    Increasing studies have shown that the patients with diabetes mellitus have an increased risk of cognitive impairment, dementia, and neurodegeneration. The present study was designed to evaluate the effect of aspirin on diabetes-associated learning and memory decline in mice. Diabetes was induced by a single intraperitoneal injection of streptozocin (150 mg/kg body weight) in C57BL/6 mice. The mice were administered with aspirin at a dose of 30 mg/kg by intragastric administration once a day for 1, 4 or 8 weeks respectively. 8 weeks after aspirin or vehicle treatment, the effect of aspirin on diabetes-associated learning and memory decline in mice was investigated by evaluating the mean escape latency and the percentage of time spent in target quadrant. The TNF-?, IL-1? contents, and acetylcholinesterase activity in hippocampus were assayed as well. The results showed that administration with aspirin for 4 weeks or 8 weeks significantly reduced the mean escape latency, the acetylcholinesterase activity, the TNF-?, IL-1? levels and increased the percentage of time spent in target quadrant. However, treatment with aspirin for 1 week did not ameliorate diabetes-associated learning and memory decline. The present study demonstrated that long-term aspirin treatment attenuates diabetes-associated learning and memory decline in mice, and that the effect of aspirin was related to its anti-inflammatory potency. PMID:20690072

  18. Immunotherapeutic effects of pentoxifylline in type 1 diabetic mice and its role in the response of T-helper lymphocytes

    PubMed Central

    Malekifard, Farin; Delirezh, Nowruz; Hobbenaghi, Rahim; Malekinejad, Hassan

    2015-01-01

    Objective(s): Pentoxifylline is an immunomodulatory and anti-inflammatory agent and is used in vascular disorders. It has been shown that pentoxifylline inhibits proinflammatory cytokines production. The purpose of this study was to investigate the therapeutic effects of pentoxifylline on the treatment of autoimmune diabetes in mice. Materials and Methods: Diabetes was induced by multiple low dose of streptozotocin (MLDS) injection (40 mg/kg/day for 5 consecutive days) in male C57BL/6 mice. After induction of diabetes, mice were treated with pentoxifylline (100 mg/kg/day IP) for 21 days. Blood glucose levels and plasma levels of insulin were measured. Splenocytes were tested for proliferation by MTT test and cytokine production by ELISA. Results: Pentoxifylline treatment prevented hyperglycemia and increased plasma insulin levels in the diabetic mice. Aside from reducing lymphocyte proliferation, pentoxifylline significantly inhibited the production of proinflammatory interleukin 17 (IL-17) as well as interferon gamma (IFN-?), while increased anti-inflammatory cytokine IL-10 as compared with those in MLDS group (diabetic control group). Conclusion: These findings indicate that pentoxifylline may have therapeutic effect against the autoimmune destruction of the pancreatic beta-cells during the development of MLDS-induced type 1 diabetes in mice. PMID:25945237

  19. Knockout of the TauT Gene Predisposes C57BL/6 Mice to Streptozotocin-Induced Diabetic Nephropathy

    PubMed Central

    Han, Xiaobin; Patters, Andrea B.; Ito, Takashi; Schaffer, Stephen W.; Chesney, Russell W.

    2015-01-01

    Diabetic nephropathy is the leading cause of end stage renal disease in the world. Although tremendous efforts have been made, scientists have yet to identify an ideal animal model that can reproduce the characteristics of human diabetic nephropathy. In this study, we hypothesize that taurine insufficiency is a critical risk factor for development of diabetic nephropathy associated with diabetes mellitus. This hypothesis was tested in vivo in TauT heterozygous (TauT+/-) and homozygous (TauT-/-) knockout in C57BL/6 background mice. We have shown that alteration of the TauT gene (also known as SLC6A6) has a substantial effect on the susceptibility to development of extensive diabetic kidney disease in both TauT+/- and TauT-/-mouse models of diabetes. These animals developed histological changes characteristic of human diabetic nephropathy that included glomerulosclerosis, nodular lesions, arteriosclerosis, arteriolar dilation, and tubulointerstitial fibrosis. Immunohistochemical staining of molecular markers of smooth muscle actin, CD34, Ki67 and collagen IV further confirmed these observations. Our results demonstrated that both homozygous and heterozygous TauT gene deletion predispose C57BL/6 mice to develop end-stage diabetic kidney disease, which closely replicates the pathological features of diabetic nephropathy in human diabetic patients. PMID:25629817

  20. Senescence-associated phenotypes in Akita diabetic mice are enhanced by absence of bradykinin B2 receptors

    PubMed Central

    Kakoki, Masao; Kizer, Catherine M.; Yi, Xianwen; Takahashi, Nobuyuki; Kim, Hyung-Suk; Bagnell, C. Robert; Edgell, Cora-Jean S.; Maeda, Nobuyo; Jennette, J. Charles; Smithies, Oliver

    2006-01-01

    We have previously reported that genetically increased angiotensin-converting enzyme levels, or absence of the bradykinin B2 receptor, increase kidney damage in diabetic mice. We demonstrate here that this is part of a more general phenomenon — diabetes and, to a lesser degree, absence of the B2 receptor, independently but also largely additively when combined, enhance senescence-associated phenotypes in multiple tissues. Thus, at 12 months of age, indicators of senescence (alopecia, skin atrophy, kyphosis, osteoporosis, testicular atrophy, lipofuscin accumulation in renal proximal tubule and testicular Leydig cells, and apoptosis in the testis and intestine) are virtually absent in WT mice, detectable in B2 receptor–null mice, clearly apparent in mice diabetic because of a dominant mutation (Akita) in the Ins2 gene, and most obvious in Akita diabetic plus B2 receptor–null mice. Renal expression of several genes that encode proteins associated with senescence and/or apoptosis (TGF-?1, connective tissue growth factor, p53, ?-synuclein, and forkhead box O1) increases in the same progression. Concomitant increases occur in 8-hydroxy-2?-deoxyguanosine, point mutations and deletions in kidney mitochondrial DNA, and thiobarbituric acid–reactive substances in plasma, together with decreases in the reduced form of glutathione in erythrocytes. Thus, absence of the bradykinin B2 receptor increases the oxidative stress, mitochondrial DNA damage, and many senescence-associated phenotypes already present in untreated Akita diabetic mice. PMID:16604193

  1. Human fibrocyte-derived exosomes accelerate wound healing in genetically diabetic mice.

    PubMed

    Geiger, Adolf; Walker, Audrey; Nissen, Erwin

    2015-11-13

    Diabetic ulcers represent a substantial societal and healthcare burden worldwide and scarcely respond to current treatment strategies. This study was addressed to evaluate the therapeutic potential of exosomes secreted by human circulating fibrocytes, a population of mesenchymal progenitors involved in normal wound healing via paracrine signaling. The exosomes released from cells sequentially stimulated with platelet-derived growth factor-BB and transforming growth factor-?1, in the presence of fibroblast growth factor 2, did not show potential immunogenicity. These exosomes exhibited in-vitro proangiogenic properties, activated diabetic dermal fibroblasts, induced the migration and proliferation of diabetic keratinocytes, and accelerated wound closure in diabetic mice in vivo. Important components of the exosomal cargo were heat shock protein-90?, total and activated signal transducer and activator of transcription 3, proangiogenic (miR-126, miR-130a, miR-132) and anti-inflammatory (miR124a, miR-125b) microRNAs, and a microRNA regulating collagen deposition (miR-21). This proof-of-concept study demonstrates the feasibility of the use of fibrocytes-derived exosomes for the treatment of diabetic ulcers. PMID:26454169

  2. Gold nanorods in an oil-base formulation for transdermal treatment of type 1 diabetes in mice.

    PubMed

    Nose, Keisuke; Pissuwan, Dakrong; Goto, Masahiro; Katayama, Yoshiki; Niidome, Takuro

    2012-06-21

    Efficient transdermal insulin delivery to the systemic circulation would bring major benefit to diabetic patients. We investigated the possibility of using gold nanorods (GNRs) that formed a complex with an edible surfactant and insulin (INS) in an oil phase to form a solid-in-oil (SO) formulation (SO-INS-GNR) for transdermal treatment of diabetes. Diabetic mice comprised the model for our study. In vitro, there was high penetration of insulin through the stratum corneum (SC) and the dermis in mouse skin treated with an SO-INS-GNR complex plus near-infrared (NIR) light irradiation. Blood glucose levels in the diabetic mice were significantly decreased after treatment with SO-INS-GNR plus irradiation. To our knowledge, this is the first study to use gold nanorods for systemic insulin delivery through the skin. The use of an SO-INS-GNR complex combined with NIR irradiation may provide the possibility of transdermal insulin delivery to diabetic patients. PMID:22622618

  3. Assessment of gastric emptying in non-obese diabetic mice using a [13C]-octanoic acid breath test.

    PubMed

    Creedon, Christopher T; Verhulst, Pieter-Jan; Choi, Kyoung M; Mason, Jessica E; Linden, David R; Szurszewski, Joseph H; Gibbons, Simon J; Farrugia, Gianrico

    2013-01-01

    Gastric emptying studies in mice have been limited by the inability to follow gastric emptying changes in the same animal since the most commonly used techniques require killing of the animals and postmortem recovery of the meal(1,2). This approach prevents longitudinal studies to determine changes in gastric emptying with age and progression of disease. The commonly used [(13)C]-octanoic acid breath test for humans(3) has been modified for use in mice(4-6) and rats(7) and we previously showed that this test is reliable and responsive to changes in gastric emptying in response to drugs and during diabetic disease progression(8). In this video presentation the principle and practical implementation of this modified test is explained. As in the previous study, NOD LtJ mice are used, a model of type 1 diabetes(9). A proportion of these mice develop the symptoms of gastroparesis, a complication of diabetes characterized by delayed gastric emptying without mechanical obstruction of the stomach(10). This paper demonstrates how to train the mice for testing, how to prepare the test meal and obtain 4 hr gastric emptying data and how to analyze the obtained data. The carbon isotope analyzer used in the present study is suitable for the automatic sampling of the air samples from up to 12 mice at the same time. This technique allows the longitudinal follow-up of gastric emptying from larger groups of mice with diabetes or other long-standing diseases. PMID:23542813

  4. Assessment of Gastric Emptying in Non-obese Diabetic Mice Using a [13C]-octanoic Acid Breath Test

    PubMed Central

    Creedon, Christopher T.; Verhulst, Pieter-Jan; Choi, Kyoung M.; Mason, Jessica E.; Linden, David R.; Szurszewski, Joseph H.; Gibbons, Simon J.; Farrugia, Gianrico

    2013-01-01

    Gastric emptying studies in mice have been limited by the inability to follow gastric emptying changes in the same animal since the most commonly used techniques require killing of the animals and postmortem recovery of the meal1,2. This approach prevents longitudinal studies to determine changes in gastric emptying with age and progression of disease. The commonly used [13C]-octanoic acid breath test for humans3 has been modified for use in mice4-6 and rats7 and we previously showed that this test is reliable and responsive to changes in gastric emptying in response to drugs and during diabetic disease progression8. In this video presentation the principle and practical implementation of this modified test is explained. As in the previous study, NOD LtJ mice are used, a model of type 1 diabetes9. A proportion of these mice develop the symptoms of gastroparesis, a complication of diabetes characterized by delayed gastric emptying without mechanical obstruction of the stomach10. This paper demonstrates how to train the mice for testing, how to prepare the test meal and obtain 4 hr gastric emptying data and how to analyze the obtained data. The carbon isotope analyzer used in the present study is suitable for the automatic sampling of the air samples from up to 12 mice at the same time. This technique allows the longitudinal follow-up of gastric emptying from larger groups of mice with diabetes or other long-standing diseases. PMID:23542813

  5. Oxytocin treatment prevents the cardiomyopathy observed in obese diabetic male db/db mice.

    PubMed

    Plante, Eric; Menaouar, Ahmed; Danalache, Bogdan A; Yip, Denis; Broderick, Tom L; Chiasson, Jean-Louis; Jankowski, Marek; Gutkowska, Jolanta

    2015-04-01

    Oxytocin (OT) is involved in the regulation of energy metabolism and in the activation of cardioprotective mechanisms. We evaluated whether chronic treatment with OT could prevent the metabolic and cardiac abnormalities associated with diabetes and obesity using the db/db mice model. Four-week-old male db/db mice and their lean nondiabetic littermates (db/+) serving as controls were treated with OT (125 ng/kg · h) or saline vehicle for a period of 12 weeks. Compared with db/+ mice, the saline-treated db/db mice developed obesity, hyperglycemia, and hyperinsulinemia. These mice also exhibited a deficient cardiac OT/natriuretic system and developed systolic and diastolic dysfunction resulting from cardiomyocyte hypertrophy, fibrosis, and apoptosis. These abnormalities were associated with increased reactive oxygen species (ROS) production, inflammation, and suppressed 5'-adenosine monophosphate kinase signaling pathway. The db/db mice displayed reduced serum levels of adiponectin and adipsin and elevated resistin. OT treatment increased circulating OT levels, significantly reduced serum resistin, body fat accumulation (19%; P<.001), fasting blood glucose levels by (23%; P<.001), and improved glucose tolerance and insulin sensitivity. OT also normalized cardiac OT receptors, atrial natriuretic peptide, and brain natriuretic peptide, expressions and prevented systolic and diastolic dysfunction as well as cardiomyocyte hypertrophy, fibrosis, and apoptosis. Furthermore, OT reduced cardiac oxidative stress and inflammation and normalized the 5'-adenosine monophosphate-activated protein kinase signaling pathway. The complete normalization of cardiac structure and function by OT treatment in db/db mice contrasted with only partial improvement of hyperglycemia and hyperinsulinemia. These results indicate that chronic treatment with OT partially improves glucose and fat metabolism and reverses abnormal cardiac structural remodeling, preventing cardiac dysfunction in db/db mice. PMID:25562615

  6. Inhibition of 11?-HSD1 by LG13 improves glucose metabolism in type 2 diabetic mice.

    PubMed

    Zhao, Leping; Pan, Yong; Peng, Kesong; Wang, Zhe; Li, Jieli; Li, Dan; Tong, Chao; Wang, Yi; Liang, Guang

    2015-10-01

    11?-hydroxysteroid dehydrogenase type 1 (11?-HSD1) controls the production of active glucocorticoid (GC) and has been proposed as a new target for the treatment of type 2 diabetes. We have previously reported that a natural product, curcumin, exhibited moderate inhibition and selectivity on 11?-HSD1. By analyzing the models of protein, microsome, cells and GCs-induced mice in vitro and in vivo, this study presented a novel curcumin analog, LG13, as a potent selective 11?-HSD1 inhibitor. In vivo, Type 2 diabetic mice were treated with LG13 for 42 days to assess the pharmacological benefits of 11?-HSD1 inhibitor on hepatic glucose metabolism. In vitro studies revealed that LG13 selectively inhibited 11?-HSD1 with IC50 values at nanomolar level and high selectivity over 11?-HSD2. Targeting 11?-HSD1, LG13 could inhibit prednisone-induced adverse changes in mice, but had no effects on dexamethasone-induced ones. Further, the 11?-HSD1 inhibitors also suppressed 11?-HSD1 and GR expression, indicating a possible positive feedback system in the 11?-HSD1/GR cycle. In type 2 diabetic mice induced by high fat diet plus low-dosage STZ injection, oral administration with LG13 for 6 weeks significantly decreased fasting blood glucose, hepatic glucose metabolism, structural disorders, and lipid deposits. LG13 exhibited better pharmacological effects in vivo than insulin sensitizer pioglitazone and potential 11?-HSD1 inhibitor PF-915275. These pharmacological and mechanistic insights on LG13 also provide us novel agents, leading structures, and strategy for the development of 11?-HSD1 inhibitors treating metabolic syndromes. PMID:26220348

  7. Chlorogenic Acid Improves Late Diabetes through Adiponectin Receptor Signaling Pathways in db/db Mice

    PubMed Central

    Jin, Shasha; Chang, Cuiqing; Zhang, Lantao; Liu, Yang; Huang, Xianren; Chen, Zhimin

    2015-01-01

    The aim of this study was to examine the effects of chlorogenic acid (CGA) on glucose and lipid metabolism in late diabetic db/db mice, as well as on adiponectin receptors and their signaling molecules, to provide evidence for CGA in the prevention of type 2 diabetes. We randomly divided 16 female db/db mice into db/db-CGA and db/db-control (CON) groups equally; db/m mice were used as control mice. The mice in both the db/db-CGA and db/m-CGA groups were administered 80 mg/kg/d CGA by lavage for 12 weeks, whereas the mice in both CON groups were given equal volumes of phosphate-buffered saline (PBS) by lavage. At the end of the intervention, we assessed body fat and the parameters of glucose and lipid metabolism in the plasma, liver and skeletal muscle tissues as well as the levels of aldose reductase (AR) and transforming growth factor-?1 (TGF-?1) in the kidneys and measured adiponectin receptors and the protein expression of their signaling molecules in liver and muscle tissues. After 12 weeks of intervention, compared with the db/db-CON group, the percentage of body fat, fasting plasma glucose (FPG) and glycosylated hemoglobin (HbA1c) in the db/db-CGA group were all significantly decreased; TGF-?1 protein expression and AR activity in the kidney were both decreased; and the adiponectin level in visceral adipose was increased. The protein expression of adiponectin receptors (ADPNRs), the phosphorylation of AMP-activated protein kinase (AMPK) in the liver and muscle, and the mRNA and protein levels of peroxisome proliferator-activated receptor alpha (PPAR-?) in the liver were all significantly greater. CGA could lower the levels of fasting plasma glucose and HbA1c during late diabetes and improve kidney fibrosis to some extent through the modulation of adiponectin receptor signaling pathways in db/db mice. PMID:25849026

  8. Hepatic Circadian-Clock System Altered by Insulin Resistance, Diabetes and Insulin Sensitizer in Mice

    PubMed Central

    Yang, Shih-Hsien; Shieh, Kun-Ruey

    2015-01-01

    Circadian rhythms are intrinsic rhythms that are coordinated with the rotation of the Earth and are also generated by a set of circadian-clock genes at the intracellular level. Growing evidence suggests a strong link between circadian rhythms and energy metabolism; however, the fundamental mechanisms remain unclear. In the present study, neonatal streptozotocin (STZ)-treated mice were used to model the molecular and physiological progress from insulin resistance to diabetes. Two-day-old male C57BL/6 mice received a single injection of STZ and were tested for non-obese, hyperglycemic and hyperinsulinemic conditions in the early stage, insulin resistance in the middle stage, and diabetes in the late stage. Gene expression levels of the hepatic circadian-clock system were examined by real-time quantitative PCR. Most of the components of the hepatic circadian-clock gene expression system, such as the mRNAs of Bmal1 (brain and muscle Arnt-like protein-1), Per2 (period 2) and Cry1 (cryptochrome 1), were elevated, and circadian patterns were retained in the early and middle stages of insulin-resistant conditions. The insulin sensitizer, rosiglitazone, returns the physiological and molecular changes associated with the diabetic phenotype to normal levels through peroxisome proliferator-activated receptor ? (PPAR?) rather than PPAR?. Early and chronic treatment with rosiglitazone has been shown to be effective to counter the diabetic condition. Over time, this effect acts to attenuate the increased gene expression levels of the hepatic circadian-clock system and delay the severity of diabetic conditions. Together, these results support an essential role for the hepatic circadian-clock system in the coordinated regulation and/or response of metabolic pathways. PMID:25799429

  9. Lentivectors Encoding Immunosuppressive Proteins Genetically Engineer Pancreatic ? Cells to Correct Diabetes in Allogeneic Mice

    PubMed Central

    Kojaoghlanian, Tsoline; Joseph, Aviva; Follenzi, Antonia; Zheng, Jian Hua; Leiser, Margarita; Fleischer, Norman; Horwitz, Marshall S.; DiLorenzo, Teresa P.; Goldstein, Harris

    2010-01-01

    The effectiveness of genetic engineering with lentivectors to protect transplanted cells from allogeneic rejection was examined using, as a model, type 1 diabetes treatment with ? cell transplantation, whose widespread use has been limited by the requirement for sustained immunosuppressive treatment to prevent graft rejection. We examined whether lentivectors expressing select immunosuppressive proteins encoded by the adenoviral genome early region 3 (AdE3) would protect transplanted ? cells from an alloimmune attack. The insulin-producing ? cell line ?TC-tet (C3HeB/FeJ-derived) was transduced with lentiviruses encoding the AdE3 proteins gp19K and RID?/?. The efficiency of lentiviral transduction of ?TC-tet cells exceeded 85%. Lentivector expression of gp19K decreased surface class I MHC expression by over 90%, while RID?/? expression inhibited cytokine-induced Fas upregulation by over 75%. ?TC-tet cells transduced with gp19K and RID?/? lentivectors, but not with a control lentivector, provided prolonged correction of hyperglycemia after transplantation into diabetic BALB/c SCID mice reconstituted with allogeneic immune effector cells or into diabetic allogeneic BALB/c mice. Thus, genetic engineering of ? cells using gp19K and RID?/? expressing lentiviral vectors may provide an alternative that has the potential to eliminate or reduce treatment with the potent immunosuppressive agents currently necessary for prolonged engraftment with transplanted islets. PMID:19112449

  10. P2X7 receptor knockout prevents streptozotocin-induced type 1 diabetes in mice.

    PubMed

    Vieira, Flávia Sarmento; Nanini, Hayandra Ferreira; Takiya, Christina Maeda; Coutinho-Silva, Robson

    2016-01-01

    Type 1 diabetes (T1D) is caused by autoimmune destruction of islet of Langerhans ?-cells. P2X7 receptors (P2X7R) modulate proinflammatory immune responses by binding extracellular ATP, a classic 'danger signal'. Here, we evaluated whether the P2X7R has a role in T1D development. P2X7(-/-) mice are resistant to TD1 induction by streptozotocin (STZ) treatment, with no increase in blood glucose, decrease in insulin-positive cells, and pancreatic islet reduction, compared to WT (C57BL/6) mice. Also, the levels of proinflammatory mediators (IL-1?, IFN-? and NO) did not increase after STZ treatment in P2X7(-/-) animals, with reduced infiltration of CD4(+), CD8(+), B220(+), CD11b(+) and CD11c(+) cells in the pancreatic lymph nodes. Treatment with a P2X7 antagonist mimicked the effect of P2X7 knockout, preventing STZ-induced diabetes. Our results show that the absence of the P2X7R provides resistance in the induction of diabetes in this model, and suggest that therapy targeting the P2X7R may be useful against clinical T1D. PMID:26483196

  11. Regulation of intestinal SGLT1 by catestatin in hyperleptinemic type 2 diabetic mice.

    PubMed

    Dominguez Rieg, Jessica A; Chirasani, Venkat R; Koepsell, Hermann; Senapati, Sanjib; Mahata, Sushil K; Rieg, Timo

    2016-01-01

    The small intestine is the major site for nutrient absorption that is critical in maintenance of euglycemia. Leptin, a key hormone involved in energy homeostasis, directly affects nutrient transport across the intestinal epithelium. Catestatin (CST), a 21-amino acid peptide derived from proprotein chromogranin A, has been shown to modulate leptin signaling. Therefore, we reasoned that leptin and CST could modulate intestinal Na(+)-glucose transporter 1 (SGLT1) expression in the context of obesity and diabetes. We found that hyperleptinemic db/db mice exhibit increased mucosal mass, associated with an enhanced proliferative response and decreased apoptosis in intestinal crypts, a finding absent in leptin-deficient ob/ob mice. Intestinal SGLT1 abundance was significantly decreased in hyperleptinemic but not leptin-deficient mice, indicating leptin regulation of SGLT1 expression. Phlorizin, a SGLT1/2 inhibitor, was without effect in an oral glucose tolerance test in db/db mice. The alterations in architecture and SGLT1 abundance were not accompanied by changes in the localization of intestinal alkaline phosphatase, indicating intact differentiation. Treatment of db/db mice with CST restored intestinal SGLT1 abundance and intestinal turnover, suggesting a cross-talk between leptin and CST, without affecting plasma leptin levels. Consistent with this hypothesis, we identified structural homology between CST and the AB-loop of leptin and protein-protein docking revealed binding of CST and leptin with the Ig-like binding site-III of the leptin receptor. In summary, downregulation of SGLT1 in an obese type 2 diabetic mouse model with hyperleptinemia is presumably mediated via the short form of the leptin receptor and reduces overt hyperglycemia. PMID:26552046

  12. Transplantation of bone marrow derived cells promotes pancreatic islet repair in diabetic mice

    SciTech Connect

    Gao Xiaodong; Song Lujun; Shen Kuntang; Wang Hongshan; Niu Weixin Qin Xinyu

    2008-06-20

    The transplantation of bone marrow (BM) derived cells to initiate pancreatic regeneration is an attractive but as-yet unrealized strategy. Presently, BM derived cells from green fluorescent protein transgenic mice were transplanted into diabetic mice. Repair of diabetic islets was evidenced by reduction of hyperglycemia, increase in number of islets, and altered pancreatic histology. Cells in the pancreata of recipient mice co-expressed BrdU and insulin. Double staining revealed {beta} cells were in the process of proliferation. BrdU{sup +} insulin{sup -} PDX-1{sup +} cells, Ngn3{sup +} cells and insulin{sup +} glucagon{sup +} cells, which showed stem cells, were also found during {beta}-cell regeneration. The majority of transplanted cells were mobilized to the islet and ductal regions. In recipient pancreas, transplanted cells simultaneously expressed CD34 but did not express insulin, PDX-1, Ngn3, Nkx2.2, Nkx6.1, Pax4, Pax6, and CD45. It is concluded that BM derived cells especially CD34{sup +} cells can promote repair of pancreatic islets. Moreover, both proliferation of {beta} cells and differentiation of pancreatic stem cells contribute to the regeneration of {beta} cells.

  13. Spironolactone treatment attenuates vascular dysfunction in type 2 diabetic mice by decreasing oxidative stress and restoring NO/GC signaling.

    PubMed

    Silva, Marcondes A B; Bruder-Nascimento, Thiago; Cau, Stefany B A; Lopes, Rheure A M; Mestriner, Fabiola L A C; Fais, Rafael S; Touyz, Rhian M; Tostes, Rita C

    2015-01-01

    Type 2 diabetes (DM2) increases the risk of cardiovascular disease. Aldosterone, which has pro-oxidative and pro-inflammatory effects in the cardiovascular system, is positively regulated in DM2. We assessed whether blockade of mineralocorticoid receptors (MR) with spironolactone decreases reactive oxygen species (ROS)-associated vascular dysfunction and improves vascular nitric oxide (NO) signaling in diabetes. Leptin receptor knockout [LepR(db)/LepR(db) (db/db)] mice, a model of DM2, and their counterpart controls [LepR(db)/LepR(+), (db/+) mice] received spironolactone (50 mg/kg body weight/day) or vehicle (ethanol 1%) via oral per gavage for 6 weeks. Spironolactone treatment abolished endothelial dysfunction and increased endothelial nitric oxide synthase (eNOS) phosphorylation (Ser(1177)) in arteries from db/db mice, determined by acetylcholine-induced relaxation and Western Blot analysis, respectively. MR antagonist therapy also abrogated augmented ROS-generation in aorta from diabetic mice, determined by lucigenin luminescence assay. Spironolactone treatment increased superoxide dismutase-1 and catalase expression, improved sodium nitroprusside and BAY 41-2272-induced relaxation, and increased soluble guanylyl cyclase (sGC) ? subunit expression in arteries from db/db mice. Our results demonstrate that spironolactone decreases diabetes-associated vascular oxidative stress and prevents vascular dysfunction through processes involving increased expression of antioxidant enzymes and sGC. These findings further elucidate redox-sensitive mechanisms whereby spironolactone protects against vascular injury in diabetes. PMID:26500555

  14. Alleviation of streptozotocin-induced diabetes in nude mice by stem cells derived from human first trimester umbilical cord.

    PubMed

    Cao, M; Zhang, J B; Dong, D D; Mou, Y; Li, K; Fang, J; Wang, Z Y; Chen, C; Zhao, J; Yie, S M

    2015-01-01

    Cells isolated from human first trimester umbilical cord perivascular layer (hFTM-PV) tissues display the pluripotent characteristics of stem cells. In this study, we examined whether hFTM-PV cells can differentiate into islet-like clusters (ILCs) in vitro, and whether transplantation of the hFTM-PV cells with and without differentiation in vitro can alleviate diabetes in nude mice. The hFTM-PV cells were differentiated into ILCs in vitro through a simple stepwise culture protocol. To examine the in vivo effects of the cells, the hFTM-PV cells with and without differentiation in vitro were transplanted into the abdominal cavity of nude mice with streptozotocin (STZ)-induced diabetes. Blood glucose levels, body weight, and the survival probability of the diabetic nude mice were then statistically analyzed. The hFTM-PV cells were successfully induced into ILCs that could release insulin in response to elevated concentrations of glucose in vitro. In transplantation experiments, we observed that mice transplanted with the undifferentiated hFTM-PV cells, embryonic body-like cell aggregations, or ILCs all demonstrated normalized hyperglycemia and showed improved survival rate compared with those without cell transplantation. The hFTM-PV cells have the ability to differentiate into ILCs in vitro and transplantations of undifferentiated and differentiated cells can alleviate STZ-induced diabetes in nude mice. This may offer a potential cell source for stem cell-based therapy for treating diabetes in the future. PMID:26505401

  15. Spironolactone treatment attenuates vascular dysfunction in type 2 diabetic mice by decreasing oxidative stress and restoring NO/GC signaling

    PubMed Central

    Silva, Marcondes A. B.; Bruder-Nascimento, Thiago; Cau, Stefany B. A.; Lopes, Rheure A. M.; Mestriner, Fabiola L. A. C.; Fais, Rafael S.; Touyz, Rhian M.; Tostes, Rita C.

    2015-01-01

    Type 2 diabetes (DM2) increases the risk of cardiovascular disease. Aldosterone, which has pro-oxidative and pro-inflammatory effects in the cardiovascular system, is positively regulated in DM2. We assessed whether blockade of mineralocorticoid receptors (MR) with spironolactone decreases reactive oxygen species (ROS)-associated vascular dysfunction and improves vascular nitric oxide (NO) signaling in diabetes. Leptin receptor knockout [LepRdb/LepRdb (db/db)] mice, a model of DM2, and their counterpart controls [LepRdb/LepR+, (db/+) mice] received spironolactone (50 mg/kg body weight/day) or vehicle (ethanol 1%) via oral per gavage for 6 weeks. Spironolactone treatment abolished endothelial dysfunction and increased endothelial nitric oxide synthase (eNOS) phosphorylation (Ser1177) in arteries from db/db mice, determined by acetylcholine-induced relaxation and Western Blot analysis, respectively. MR antagonist therapy also abrogated augmented ROS-generation in aorta from diabetic mice, determined by lucigenin luminescence assay. Spironolactone treatment increased superoxide dismutase-1 and catalase expression, improved sodium nitroprusside and BAY 41-2272-induced relaxation, and increased soluble guanylyl cyclase (sGC) ? subunit expression in arteries from db/db mice. Our results demonstrate that spironolactone decreases diabetes-associated vascular oxidative stress and prevents vascular dysfunction through processes involving increased expression of antioxidant enzymes and sGC. These findings further elucidate redox-sensitive mechanisms whereby spironolactone protects against vascular injury in diabetes. PMID:26500555

  16. Effect of diet-induced obesity or type 1 or type 2 diabetes on corneal nerves and peripheral neuropathy in C57Bl/6J mice.

    PubMed

    Yorek, Matthew S; Obrosov, Alexander; Shevalye, Hanna; Holmes, Amey; Harper, Matthew M; Kardon, Randy H; Yorek, Mark A

    2015-03-01

    We determined the impact diet-induced obesity (DIO) and types 1 and 2 diabetes have on peripheral neuropathy with emphasis on corneal nerve structural changes in C57Bl/6J mice. Endpoints examined included nerve conduction velocity, response to thermal and mechanical stimuli and innervation of the skin and cornea. DIO mice and to a greater extent type 2 diabetic mice were insulin resistant. DIO and both types 1 and 2 diabetic mice developed motor and sensory nerve conduction deficits. In the cornea of DIO and type 2 diabetic mice there was a decrease in sub-epithelial corneal nerves, innervation of the corneal epithelium, and corneal sensitivity. Type 1 diabetic mice did not present with any significant changes in corneal nerve structure until after 20?weeks of hyperglycemia. DIO and type 2 diabetic mice developed corneal structural damage more rapidly than type 1 diabetic mice although hemoglobin A1 C values were significantly higher in type 1 diabetic mice. This suggests that DIO with or without hyperglycemia contributes to development and progression of peripheral neuropathy and nerve structural damage in the cornea. PMID:25858759

  17. Attenuation of atherosclerotic lesions in diabetic apolipoprotein E-deficient mice using gene silencing of macrophage migration inhibitory factor

    PubMed Central

    Sun, Hui; Zhang, XianJun; Zhao, Lei; Zhen, Xi; Huang, ShanYing; Wang, ShaSha; He, Hong; Liu, ZiMo; Xu, NaNa; Yang, FaLin; Qu, ZhongHua; Ma, ZhiYong; Zhang, Cheng; Zhang, Yun; Hu, Qin

    2015-01-01

    Macrophage migration inhibitory factor (MIF) involves the pathogenesis of atherosclerosis (AS) and increased plasma MIF levels in diabetes mellitus (DM) patients are associated with AS. Here, we have been suggested that MIF could be a critical contributor for the pathological process of diabetes-associated AS by using adenovirus-mediated RNA interference. First, streptozotocin (STZ)-induced diabetic animal model was constructed in 114 apolipoprotein E-deficient mice (apoE?/? mice) fed on a regular chow diet. Then, the animals were randomly divided into three groups: Adenovirus-mediated MIF interference (Ad-MIFi), Ad-enhanced green fluorescent protein (EGFP) and normal saline (NS) group (n ? 33/group). Non-diabetic apoE?/? mice (n = 35) were served as controls. Ad-MIFi, Ad-EGFP and NS were, respectively, injected into the tail vein of mice from Ad-MIFi, Ad-EGFP and NS group, which were injected repeatedly 4 weeks later. Physical, biochemical, morphological and molecular parameters were measured. The results showed that diabetic apoE?/? mice had significantly aggravated atherosclerotic lesions. MIF gene interference attenuated atherosclerotic lesions and stabilized atheromatous plaque, accompanied by the decreased macrophages and lipids deposition and inflammatory cytokines production, improved glucose intolerance and plasma cholesterol level, the decreased ratio of matrix matalloproteinase-2/tissue inhibitor of metalloproteinase-1 and plaque instability index. An increased expression of MIF and its ligand CD74 was also detected in the diabetic patients with coronary artery disease. The results suggest that MIF gene interference is able to inhibit atherosclerotic lesions and increase plaque stability in diabetic apoE?/?mice. MIF inhibition could be a novel and promising approach to the treatment of DM-associated AS. PMID:25661015

  18. Chronic inhibition of endoplasmic reticulum stress and inflammation prevents ischaemia-induced vascular pathology in type II diabetic mice.

    PubMed

    Amin, Ali; Choi, Soo-kyoung; Galan, Maria; Kassan, Modar; Partyka, Megan; Kadowitz, Philip; Henrion, Daniel; Trebak, Mohamed; Belmadani, Souad; Matrougui, Khalid

    2012-06-01

    Endoplasmic reticulum (ER) stress and inflammation are important mechanisms that underlie many of the serious consequences of type II diabetes. However, the role of ER stress and inflammation in impaired ischaemia-induced neovascularization in type II diabetes is unknown. We studied ischaemia-induced neovascularization in the hind-limb of 4-week-old db - /db- mice and their controls treated with or without the ER stress inhibitor (tauroursodeoxycholic acid, TUDCA, 150 mg/kg per day) and interleukin-1 receptor antagonist (anakinra, 0.5 µg/mouse per day) for 4 weeks. Blood pressure was similar in all groups of mice. Blood glucose, insulin levels, and body weight were reduced in db - /db- mice treated with TUDCA. Increased cholesterol and reduced adiponectin in db - /db- mice were restored by TUDCA and anakinra treatment. ER stress and inflammation in the ischaemic hind-limb in db - /db- mice were attenuated by TUDCA and anakinra treatment. Ischaemia-induced neovascularization and blood flow recovery were significantly reduced in db - /db- mice compared to control. Interestingly, neovascularization and blood flow recovery were restored in db - /db- mice treated with TUDCA or anakinra compared to non-treated db - /db- mice. TUDCA and anakinra enhanced eNOS-cGMP, VEGFR2, and reduced ERK1/2 MAP-kinase signalling, while endothelial progenitor cell number was similar in all groups of mice. Our findings demonstrate that the inhibition of ER stress and inflammation prevents impaired ischaemia-induced neovascularization in type II diabetic mice. Thus, ER stress and inflammation could be potential targets for a novel therapeutic approach to prevent impaired ischaemia-induced vascular pathology in type II diabetes. PMID:22081301

  19. SGLT2 inhibitor therapy improves blood glucose but does not prevent diabetic bone disease in diabetic DBA/2J male mice.

    PubMed

    Thrailkill, Kathryn M; Clay Bunn, R; Nyman, Jeffry S; Rettiganti, Mallikarjuna R; Cockrell, Gael E; Wahl, Elizabeth C; Uppuganti, Sasidhar; Lumpkin, Charles K; Fowlkes, John L

    2016-01-01

    Persons with type 1 and type 2 diabetes have increased fracture risk, attributed to deficits in the microarchitecture and strength of diabetic bone, thought to be mediated, in part, by the consequences of chronic hyperglycemia. Therefore, to examine the effects of a glucose-lowering SGLT2 inhibitor on blood glucose (BG) and bone homeostasis in a model of diabetic bone disease, male DBA/2J mice with or without streptozotocin (STZ)-induced hyperglycemia were fed chow containing the SGLT2 inhibitor, canagliflozin (CANA), or chow without drug, for 10weeks of therapy. Thereafter, serum bone biomarkers were measured, fracture resistance of cortical bone was assessed by ?CT analysis and a three-point bending test of the femur, and vertebral bone strength was determined by compression testing. In the femur metaphysis and L6 vertebra, long-term diabetes (DM) induced deficits in trabecular bone microarchitecture. In the femur diaphysis, a decrease in cortical bone area, cortical thickness and minimal moment of inertia occurred in DM (p<0.0001, for all) while cortical porosity was increased (p<0.0001). These DM changes were associated with reduced fracture resistance (decreased material strength and toughness; decreased structural strength and rigidity; p<0.001 for all). Significant increases in PTH (p<0.0001), RatLAPs (p=0.0002), and urine calcium concentration (p<0.0001) were also seen in DM. Canagliflozin treatment improved BG in DM mice by ~35%, but did not improve microarchitectural parameters. Instead, in canagliflozin-treated diabetic mice, a further increase in RatLAPs was evident, possibly suggesting a drug-related intensification of bone resorption. Additionally, detrimental metaphyseal changes were noted in canagliflozin-treated control mice. Hence, diabetic bone disease was not favorably affected by canagliflozin treatment, perhaps due to insufficient glycemic improvement. Instead, in control mice, long-term exposure to SGLT2 inhibition was associated with adverse effects on the trabecular compartment of bone. PMID:26211996

  20. Disruption of Nrf2 Synergizes with High Glucose to Cause Heightened Myocardial Oxidative Stress and Severe Cardiomyopathy in Diabetic Mice

    PubMed Central

    He, Xiaoqing; Ma, Qiang

    2015-01-01

    High glucose-induced oxidative stress is a major contributing mechanism to the development of diabetic cardiomyopathy. Nrf2 is an emerging critical regulator of cellular defense against oxidative damage. The role of Nrf2 in diabetic cardiomyopathy was investigated in vivo. Streptozotocin (STZ) induced diabetes in Nrf2 knockout (KO) mice that rapidly progressed to severe conditions with high mortality within two weeks of injection; whereas, in wild type (WT) mice, diabetes was less severe with no death. Severe myocardial lesions were observed in diabetic KO mice that had high, sublethal levels of blood glucose including: (a) irregular myocardial arrangements, myofibrillar discontinuation, and cell death; (b) reduced electron density, discontinuation of myocardial fibers, and mitochondrial damage; and (c) markedly reduced contractility of the cardiomyocytes to ?-agonist stimulation. Parallel to severe cardiomyopathy, the diabetic KO hearts showed: (a) increased apoptosis as revealed by TUNEL and PARP1 cleavage assays; (b) infiltration of granulocytes and macrophages as well as fibrosis indicating robust inflammatory response; and (c) heightened oxidative stress as evidenced by increased levels of 8-hydroxydeoxyquanine, free malondialdehyde, and 3-nitrotyrosine. Increased oxidative stress in the KO hearts was attributed to decrease or loss of the basal and induced expression of Nrf2-dependent cytoprotective genes. Our findings demonstrate that loss of Nrf2 function synergizes with high glucose to cause heightened oxidative stress in the heart leading to severe diabetic cardiomyopathy.

  1. Oral administration of PDX1 confers protection against insulitis in the non-obese diabetic (NOD) mice.

    PubMed

    Lin, Peng; Li, Wenjuan; Yao, Zhina; Sun, Yu; Wang, Lingshu; Li, Shiwu; Chen, Li

    2015-10-30

    Type 1 diabetes is a T cell-mediated organ-specific autoimmune disease. Antigen-specific immune intervention allows the selective targeting of autoreactive T cell, while leaving the remainder of the immune system intact. However, immune intervention for type 1 diabetes has not yielded perfect results clinically. In our paper published previously, we asked whether pancreatic duodenal home box 1 (PDX1) is a target of anti-islet autoimmunity in type 1 diabetes. In this experiment, we assessed the therapeutic effect of oral administration of PDX1 on diabetes development of 4-week-old non-obese diabetic (NOD) mice. The results indicate that PDX1 immunization is an effective intervention strategy for delaying the onset of diabetes in NOD mice in association with: 1) reduced insulitis; 2) suppression of destructive autoreactive T cells; 3) augmentation of regulatory T cells; 4) a shift in cytokine production. The present observations suggest that immunization with PDX1 modulates immune cell responses in NOD mice, raising the possibility that it is beneficial in ameliorating autoimmune destruction of beta-cells and delaying type 1 diabetes development clinically. PMID:26403969

  2. Inhibition of Autoimmune Diabetes in NOD Mice by miRNA Therapy

    PubMed Central

    Wang, Duncheng; Shanina, Iryna; Toyofuku, Wendy M.; Horwitz, Marc S.; Scott, Mark D.

    2015-01-01

    Autoimmune destruction of the pancreatic islets in Type 1 diabetes is mediated by both increased proinflammatory (Teff) and decreased regulatory (Treg) T lymphocytes resulting in a significant decrease in the Treg:Teff ratio. The non-obese diabetic (NOD) mouse is an excellent in vivo model for testing potential therapeutics for attenuating the decrease in the Treg:Teff ratio and inhibiting disease pathogenesis. Here we show for the first time that a bioreactor manufactured therapeutic consisting of a complex of miRNA species (denoted as TA1) can effectively reset the NOD immune system from a proinflammatory to a tolerogenic state thus preventing or delaying autoimmune diabetes. Treatment of NOD mice with TA1 resulted in a systemic broad-spectrum upregulation of tolerogenic T cell subsets with a parallel downregulation of Teff subsets yielding a dramatic increase in the Treg:Teff ratio. Moreover, the murine-derived TA1 was highly effective in the inhibition of allorecognition of HLA-disparate human PBMC. TA1 demonstrated dose-responsiveness and exhibited equivalent or better inhibition of allorecognition driven proliferation than etanercept (a soluble TNF receptor). These findings demonstrate that miRNA-based therapeutics can effectively attenuate or arrest autoimmune disease processes and may be of significant utility in a broad range of autoimmune diseases including Type 1 diabetes. PMID:26674203

  3. Urtica dioica extract attenuates depressive like behavior and associative memory dysfunction in dexamethasone induced diabetic mice.

    PubMed

    Patel, Sita Sharan; Udayabanu, Malairaman

    2014-03-01

    Evidences suggest that glucocorticoids results in depression and is a risk factor for type 2 diabetes. Further diabetes induces oxidative stress and hippocampal dysfunction resulting in cognitive decline. Traditionally Urtica dioica has been used for diabetes mellitus and cognitive dysfunction. The present study investigated the effect of the hydroalcoholic extract of Urtica dioica leaves (50 and 100 mg/kg, p.o.) in dexamethasone (1 mg/kg, i.m.) induced diabetes and its associated complications such as depressive like behavior and cognitive dysfunction. We observed that mice administered with chronic dexamethasone resulted in hypercortisolemia, oxidative stress, depressive like behavior, cognitive impairment, hyperglycemia with reduced body weight, increased water intake and decreased hippocampal glucose transporter-4 (GLUT4) mRNA expression. Urtica dioica significantly reduced hyperglycemia, plasma corticosterone, oxidative stress and depressive like behavior as well as improved associative memory and hippocampal GLUT4 mRNA expression comparable to rosiglitazone (5 mg/kg, p.o.). Further, Urtica dioica insignificantly improved spatial memory and serum insulin. In conclusion, Urtica dioica reversed dexamethasone induced hyperglycemia and its associated complications such as depressive like behavior and cognitive dysfunction. PMID:24435938

  4. Inhibition of Autoimmune Diabetes in NOD Mice by miRNA Therapy.

    PubMed

    Wang, Duncheng; Shanina, Iryna; Toyofuku, Wendy M; Horwitz, Marc S; Scott, Mark D

    2015-01-01

    Autoimmune destruction of the pancreatic islets in Type 1 diabetes is mediated by both increased proinflammatory (Teff) and decreased regulatory (Treg) T lymphocytes resulting in a significant decrease in the Treg:Teff ratio. The non-obese diabetic (NOD) mouse is an excellent in vivo model for testing potential therapeutics for attenuating the decrease in the Treg:Teff ratio and inhibiting disease pathogenesis. Here we show for the first time that a bioreactor manufactured therapeutic consisting of a complex of miRNA species (denoted as TA1) can effectively reset the NOD immune system from a proinflammatory to a tolerogenic state thus preventing or delaying autoimmune diabetes. Treatment of NOD mice with TA1 resulted in a systemic broad-spectrum upregulation of tolerogenic T cell subsets with a parallel downregulation of Teff subsets yielding a dramatic increase in the Treg:Teff ratio. Moreover, the murine-derived TA1 was highly effective in the inhibition of allorecognition of HLA-disparate human PBMC. TA1 demonstrated dose-responsiveness and exhibited equivalent or better inhibition of allorecognition driven proliferation than etanercept (a soluble TNF receptor). These findings demonstrate that miRNA-based therapeutics can effectively attenuate or arrest autoimmune disease processes and may be of significant utility in a broad range of autoimmune diseases including Type 1 diabetes. PMID:26674203

  5. Staphylococcus enterotoxin B-induced T cells can efficaciously protect against type 1 diabetes in non-obese diabetic mice

    PubMed Central

    Guo, Yelei; Xia, Lei; Zhang, Shilun

    2015-01-01

    Type 1 diabetes (T1D), an autoimmune disease, can be protected against by natural killer T (NKT) cells. Several attempts demonstrate that NKT cells also can be produced by inducing with Staphylococcus enterotoxin B (SEB) in addition to its classical activated antigen ?-galactosylceramide. Here, we examined a potential usage of SEB-induced T (SEB-T) cells for the treatment of T1D. We established the immunophenotypes of SEB-T cells via flow cytometry, and in consequence, enriched in CD8+NKT cells after SEB stimulated. A high level of transforming growth factor ? (TGF-?), detected by RT-PCR and ELISA, was first observed to be expressed and secreted by these SEB-T cells. Mixed lymphocyte reactions indicated that SEB-T cells could not produce a response to mitogens and allogeneic lymphocyte, and can inhibit lymphocytes response to mitogens. In an animal model, our data indicated that infusion of SEB-T cells in non-obese diabetic mice was well tolerated and could ameliorate hyperglycemia and maintain the blood glucose nearly on normal level until sacrifice. Strikingly, infusion of SEB-T cells resulted in an increase in the serum TGF-? level. These data raise the possibility that SEB-T cells can protect against T1D, which is associated with NKT cells generated in these SEB-induced cells. PMID:26648772

  6. Staphylococcus enterotoxin B-induced T cells can efficaciously protect against type 1 diabetes in non-obese diabetic mice.

    PubMed

    Guo, Yelei; Xia, Lei; Zhang, Shilun; Zhong, Jiang; Chen, Yu

    2015-01-01

    Type 1 diabetes (T1D), an autoimmune disease, can be protected against by natural killer T (NKT) cells. Several attempts demonstrate that NKT cells also can be produced by inducing with Staphylococcus enterotoxin B (SEB) in addition to its classical activated antigen ?-galactosylceramide. Here, we examined a potential usage of SEB-induced T (SEB-T) cells for the treatment of T1D. We established the immunophenotypes of SEB-T cells via flow cytometry, and in consequence, enriched in CD8(+)NKT cells after SEB stimulated. A high level of transforming growth factor ? (TGF-?), detected by RT-PCR and ELISA, was first observed to be expressed and secreted by these SEB-T cells. Mixed lymphocyte reactions indicated that SEB-T cells could not produce a response to mitogens and allogeneic lymphocyte, and can inhibit lymphocytes response to mitogens. In an animal model, our data indicated that infusion of SEB-T cells in non-obese diabetic mice was well tolerated and could ameliorate hyperglycemia and maintain the blood glucose nearly on normal level until sacrifice. Strikingly, infusion of SEB-T cells resulted in an increase in the serum TGF-? level. These data raise the possibility that SEB-T cells can protect against T1D, which is associated with NKT cells generated in these SEB-induced cells. PMID:26648772

  7. Functional immunomics: Microarray analysis of IgG autoantibody repertoires predicts the future response of mice to induced diabetes

    PubMed Central

    Quintana, Francisco J.; Hagedorn, Peter H.; Elizur, Gad; Merbl, Yifat; Domany, Eytan; Cohen, Irun R.

    2004-01-01

    One's present repertoire of antibodies encodes the history of one's past immunological experience. Can the present autoantibody repertoire be consulted to predict resistance or susceptibility to the future development of an autoimmune disease? Here, we developed an antigen microarray chip and used bioinformatic analysis to study a model of type 1 diabetes developing in nonobese diabetic male mice in which the disease was accelerated and synchronized by exposing the mice to cyclophosphamide at 4 weeks of age. We obtained sera from 19 individual mice, treated the mice to induce cyclophosphamide-accelerated diabetes (CAD), and found, as expected, that 9 mice became severely diabetic, whereas 10 mice permanently resisted diabetes. We again obtained serum from each mouse after CAD induction. We then analyzed, by using rank-order and superparamagnetic clustering, the patterns of antibodies in individual mice to 266 different antigens spotted on the chip. A selected panel of 27 different antigens (10% of the array) revealed a pattern of IgG antibody reactivity in the pre-CAD sera that discriminated between the mice resistant or susceptible to CAD with 100% sensitivity and 82% specificity (P = 0.017). Surprisingly, the set of IgG antibodies that was informative before CAD induction did not separate the resistant and susceptible groups after the onset of CAD; new antigens became critical for post-CAD repertoire discrimination. Thus, at least for a model disease, present antibody repertoires can predict future disease, predictive and diagnostic repertoires can differ, and decisive information about immune system behavior can be mined by bioinformatic technology. Repertoires matter. PMID:15308778

  8. Hypoglycemic effect and mechanism of honokiol on type 2 diabetic mice

    PubMed Central

    Sun, Jing; Fu, Xueqi; Liu, Ye; Wang, Yongsen; Huo, Bo; Guo, Yidi; Gao, Xuefeng; Li, Wannan; Hu, Xin

    2015-01-01

    Background Honokiol is one of the main bioactive constituents of the traditional Chinese herbal drug Magnolia bark (Cortex Magnoliae officinalis, Hou Po). The aim of this study was to probe its anti-type 2 diabetes mellitus effects and the underlying mechanism. Methods Type 2 diabetic mouse model was established by intraperitoneally injecting with streptozotocin. Fasting blood glucose, body weight, and lipid profile were measured. The subcutaneous adipose tissue, skeletal muscle, and liver were isolated as well as homogenized. The phospho-insulin receptor ?-subunit (IR?), IR?, phospho-AKT, AKT, phospho-ERK1/2, ERK1/2, phosphotyrosine, and actin were examined by Western blot assay. Cell viability or cytotoxicity was analyzed by using MTT method. The inhibitory potencies of honokiol on the protein tyrosine phosphatase 1B (PTP1B) activity were performed in reaction buffer. Molecular docking and dynamic simulation were also analyzed. Results In in vivo studies, oral treatment with 200 mg/kg honokiol for 8 weeks significantly decreases the fasting blood glucose in type 2 diabetes mellitus mice. The phosphorylations of the IR? and the downstream insulin signaling factors including AKT and ERK1/2 significantly increase in adipose, skeletal muscle, and liver tissue of the honokiol-treated mice. Moreover, honokiol enhanced the insulin-stimulated phosphorylations of IR?, AKT, and ERK1/2 in a dose-dependent manner in C2C12 myotube cells. Meanwhile, honokiol enhanced insulin-stimulated GLUT4 translocation. Importantly, honokiol exhibited reversible competitive inhibitory activity against PTP1B with good selectivity in vitro and in vivo. Furthermore, using molecular docking and dynamic simulation approaches, we determined the potential binding mode of honokiol to PTP1B at an atomic level. Conclusion These findings indicated the hypoglycemic effects of honokiol and its mechanism that honokiol improved the insulin sensitivity by targeting PTP1B. Therefore, our study may highlight honokiol as a promising insulin sensitizer for the therapy of type 2 diabetes. PMID:26674084

  9. Antioxidant effect of Lagerstroemia speciosa Pers (banaba) leaf extract in streptozotocin-induced diabetic mice.

    PubMed

    Saumya, S M; Basha, P Mahaboob

    2011-02-01

    Aqueous leaf extract of L. speciosa (banaba) effectively decreased the blood glucose in streptozotocin-induced diabetic mice after 15th day of banaba exposure. Further, banaba leaf extract have the potential to inhibit lipid peroxidation and effectively intercept/neutralize reactive oxygen species such as super oxide, H2O2 and NO based free radicals. The aqueous banaba leaf extract (150 mg/kg bodyweight) duly reduced STZ generated reactive intermediates and radical species helping to regulate normal levels of antioxidative markers like superoxide dismutase, catalase, glutathione-S-transferase and reduced glutathione. PMID:21428214

  10. Ay allele promotes azoxymethane-induced colorectal carcinogenesis by macrophage migration in hyperlipidemic/diabetic KK mice.

    PubMed

    Ito, Kumiko; Ishigamori, Rikako; Mutoh, Michihiro; Ohta, Toshihiro; Imai, Toshio; Takahashi, Mami

    2013-07-01

    The incidence of colorectal cancer has been increasing and is associated with obesity and diabetes. We have found that type 2 diabetes model KK-Ay/TaJcl (KK-Ay) mice develop tumors within a short period after treatment with azoxymethane (AOM). However, factors that contribute to the promotion of carcinogenesis have not been clarified. Therefore, we looked at the genetic background of KK-Ay, including two genetic characteristics of KK/TaJcl (KK) mice and C57BL/6J-Ham-Ay/+ (Ay) mice, compared with other non-obese and non-diabetic mouse strains C57BL/6J and ICR, and induced colorectal premalignant lesions, aberrant crypt foci (ACF), and tumors using AOM (150 ?g/mouse/week for 4 weeks and 200 ?g/mouse/week for 6 weeks, respectively). The mice with a diabetes feature, KK-Ay and KK, developed significantly more ACF, 67 and 61 per mouse, respectively, whereas ICR, Ay, and C57BL/6J mice developed 42, 24, and 18 ACF/mouse, respectively, at 17 weeks of age. Serum insulin and triglyceride levels in KK-Ay and KK mice were quite high compared with other non-diabetic mouse strains. Interestingly, KK-Ay mice developed more colorectal tumors (2.7 ± 2.3 tumor/mouse) than KK mice (1.2 ± 1.1 tumor/mouse) at 25 weeks of age, in spite of similar diabetic conditions. The colon cancers that developed in both KK-Ay and KK mice showed similar activation of ?-catenin signaling. However, mRNA levels of inflammatory factors related to the activation of macrophages were significantly higher in colorectal cancer of KK-Ay mice than in KK. These data indicate that factors such as insulin resistance and dyslipidemia observed in obese and diabetic patients could be involved in susceptibility to colorectal carcinogenesis. In addition, increase of tumor-associated macrophages may play important roles in the stages of promotion of colorectal cancer. PMID:23551905

  11. Mast cells control insulitis and increase Treg cells to confer protection against STZ-induced type 1 diabetes in mice.

    PubMed

    Carlos, Daniela; Yaochite, Juliana N U; Rocha, Fernanda A; Toso, Vanina D; Malmegrim, Kelen C R; Ramos, Simone G; Jamur, Maria C; Oliver, Constance; Camara, Niels O; Andrade, Marcus V M; Cunha, Fernando Q; Silva, João S

    2015-10-01

    Quantitative alterations in mast cell numbers in pancreatic lymph nodes (PLNs) have been reported to be associated with type 1 diabetes (T1D) progression, but their potential role during T1D remains unclear. In this study, we evaluated the role of mast cells in T1D induced by multiple low-dose streptozotocin (MLD-STZ) treatments, using two strains of mast cell-deficient mice (W/W(v) or Wsh/Wsh) and the adoptive transfer of mast cells. Mast cell deficient mice developed severe insulitis and accelerated hyperglycemia, with 100% of mice becoming diabetic compared to their littermates. In parallel, these diabetic mice had decreased numbers of T regulatory (Treg) cells in the PLNs. Additionally, mast cell deficiency caused a significant reduction in IL-10, TGF-?, and IL-6 expression in the pancreatic tissue. Interestingly, IL-6-deficient mice are more susceptible to T1D associated with reduced Treg-cell numbers in the PLNs, but mast cell transfer from wild-type mice induced protection to T1D in these mice. Finally, mast cell adoptive transfer prior to MLD-STZ administration conferred resistance to T1D, promoted increased Treg cells, and decreased IL-17-producing T cells in the PLNs. Taken together, our results indicate that mast cells are implicated in resistance to STZ-induced T1D via an immunological tolerance mechanism mediated by Treg cells. PMID:26234742

  12. Supplementary effect by harvest period of Lentinus edodes on the levels of blood glucose and serum lipid in diabetic KK mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was carried out to investigate the effect of Lentinus edodes which were harvested at different times of maturity on blood glucose and lipid levels in diabetic mice. The diabetic KK mice were fed diet supplemented with Lentinus edodes harvested early (LE) or late (LL) for eight weeks, and ...

  13. Anti-diabetic effect of amorphastilbol through PPAR?/? dual activation in db/db mice

    SciTech Connect

    Lee, Woojung; Ham, Jungyeob; Kwon, Hak Cheol; Kim, Yong Kee; Kim, Su-Nam

    2013-03-01

    Highlights: ? Amorphastilbol stimulates the transcriptional activities of both PPAR? and PPAR?. ? Amorphastilbol improves glucose and lipid impairment in db/db mice. ? There are no side effects, such as hepatomegaly, in amorphastilbol-treated mice. ? Amorphastilbol can be used as a potential therapeutic agent against T2DM. - Abstract: Peroxisome proliferator-activated receptors (PPARs) have been considered as desirable targets for metabolic syndrome treatments, even though their specific agonists have several side effects, including body weight gain, edema, and tissue failure. The effects of amorphastilbol (APH) on glucose- and lipid metabolism were investigated with in vitro 3T3-L1 adipocyte systems and in vivo db/db mice model. APH selectively stimulates the transcriptional activities of both PPAR? and PPAR?, which are able to enhance fatty acid oxidation and glucose utilization. Furthermore, APH improves glucose and lipid impairment in db/db mice. More importantly, there are no significant side effects, such as weight gain or hepatomegaly, in APH-treated animals, implying that APH do not adversely affect liver or lipid metabolism. All our data suggest that APH can be used as potential therapeutic agents against type 2 diabetes and related metabolic disorders, including obesity, by enhancing glucose and lipid metabolism.

  14. Extract of Ginkgo Biloba Ameliorates Streptozotocin-Induced Type 1 Diabetes Mellitus and High-Fat Diet-Induced Type 2 Diabetes Mellitus in Mice

    PubMed Central

    Rhee, Ki-Jong; Lee, Chang Gun; Kim, Sung Woo; Gim, Dong-Hyeon; Kim, Hyun-Cheol; Jung, Bae Dong

    2015-01-01

    Diabetes mellitus (DM) is caused by either destruction of pancreatic ?-cells (type 1 DM) or unresponsiveness to insulin (type 2 DM). Conventional therapies for diabetes mellitus have been developed but still needs improvement. Many diabetic patients have complemented conventional therapy with alternative methods including oral supplementation of natural products. In this study, we assessed whether Ginkgo biloba extract (EGb) 761 could provide beneficial effects in the streptozotocin-induced type 1 DM and high-fat diet-induced type 2 DM murine model system. For the type 1 DM model, streptozotocin-induced mice were orally administered EGb 761 for 10 days prior to streptozotocin injection and then again administered EGb 761 for an additional 10 days. Streptozotocin-treated mice administered EGb 761 exhibited lower blood triglyceride levels, lower blood glucose levels and higher blood insulin levels compared to streptozotocin-treated mice. Furthermore, liver LPL and liver PPAR-? were increased whereas IL-1? and TNF-? were decreased in streptozotocin-injected mice treated with EGb 761 compared to mice injected with streptozotocin alone. For the type 2 DM model, mice were given high-fat diet for 60 days and then orally administered EGb 761 every other day for 80 days. We found that mice given a high-fat diet and EGb 761 showed decreased blood triglyceride levels, increased liver LPL, increased liver PPAR-? and decreased body weight compared to mice given high-fat diet alone. These results suggest that EGb 761 can exert protective effects in both type 1 and type 2 DM murine models. PMID:26664261

  15. Anti-Diabetic, Anti-Oxidant and Anti-Hyperlipidemic Activities of Flavonoids from Corn Silk on STZ-Induced Diabetic Mice.

    PubMed

    Zhang, Yan; Wu, Liying; Ma, Zhongsu; Cheng, Jia; Liu, Jingbo

    2015-01-01

    Corn silk is a well-known ingredient frequently used in traditional Chinese herbal medicines. This study was designed to evaluate the anti-diabetic, anti-oxidant and anti-hyperlipidemic activities of crude flavonoids extracted from corn silk (CSFs) on streptozotocin (STZ)-induced diabetic mice. The results revealed that treatment with 300 mg/kg or 500 mg/kg of CSFs significantly reduced the body weight loss, water consumption, and especially the blood glucose (BG) concentration of diabetic mice, which indicated their potential anti-diabetic activities. Serum total superoxide dismutase (SOD) and malondialdehyde (MDA) assays were also performed to evaluate the anti-oxidant effects. Besides, several serum lipid values including total cholesterol (TC), triacylglycerol (TG), low density lipoprotein cholesterol (LDL-C) were reduced and the high density lipoprotein cholesterol level (HDL-C) was increased. The anti-diabetic, anti-oxidant and anti-hyperlipidemic effect of the CSFs suggest a potential therapeutic treatment for diabetic conditions. PMID:26703560

  16. Co-regulation of SREBP-1 and mTOR ameliorates lipid accumulation in kidney of diabetic mice.

    PubMed

    Wang, Hui; Zhu, Lin; Hao, Jun; Duan, Huijun; Liu, Shuxia; Zhao, Song; Liu, Qingjuan; Liu, Wei

    2015-08-01

    SREBP-1 and mTOR have been proved to involve in renal lipid metabolism of diabetes mellitus. In the present study, we investigated the effect of co-regulation of SREBP-1 and mTOR on renal lipid metabolism using diabetic mice and cultured renal tubular cells. The results showed that compared with those in high glucose-stimulated HKC cells single transfected with shRNA-SREBP-1 vector, the level of SREBP-1 protein were significantly reduced by 64.1% followed by decreased FASN mRNA, ACC mRNA, ADRP protein and lipid droplets in HKC cells co-transfected with shRNA-SREBP-1 vector and kinase-dead mTOR vector. Furthermore, diabetic mice co-injected with shRNA-SREBP-1 vector and kinase-dead mTOR vector showed that renal SREBP-1 protein, FASN mRNA and ACC mRNA were respectively decreased by 34.6%, 45.9%, 22.0% in comparison with those in diabetic mice single injected with shRNA-SREBP-1 vector accompanied by reduced ADRP protein and triglyceride content. In the end our study suggests that co-regulation of SREBP-1 and mTOR in kidney of diabetic mice is more effective in lowering renal lipogenesis than only regulation of SREBP-1. PMID:26112216

  17. Immune Depletion in Combination with Allogeneic Islets Permanently Restores Tolerance to Self-Antigens in Diabetic NOD Mice

    PubMed Central

    Gagliani, Nicola; Jofra, Tatiana; Posgai, Amanda L.; Atkinson, Mark A.; Battaglia, Manuela

    2015-01-01

    The destruction of beta cells in type 1 diabetes (T1D) results in loss of insulin production and glucose homeostasis. Treatment of non-obese diabetic (NOD) mice with immune-depleting/modulating agents (e.g., anti-CD3, murine anti-thymocyte-globulin (mATG)) can lead to diabetes reversal. However, for preclinical studies with these and other agents seeking to reverse disease at onset, the necessity for exogenous insulin administration is debated. Spontaneously diabetic NOD mice were treated with a short-course of mATG and insulin provided as drug therapy or by way of allogeneic islet implants. Herein we demonstrate that exogenous insulin administration is required to achieve disease reversal with mATG in NOD mice. Unexpectedly, we also observed that provision of insulin by way of allogeneic islet implantation in combination with mATG leads to a pronounced reversal of diabetes as well as restoration of tolerance to self-islets. Expansion/induction of regulatory cells was observed in NOD mice stably cured with mATG and allogeneic islets. These data suggest that transient provision of allogeneic insulin-producing islets might provide a temporary window for immune depletion to be more effective and instilling stable tolerance to endogenous beta cells. These findings support the use of a never before explored approach for preserving beta cell function in patients with recent onset T1D. PMID:26580221

  18. Compound A, a selective glucocorticoid receptor agonist, inhibits immunoinflammatory diabetes, induced by multiple low doses of streptozotocin in mice

    PubMed Central

    Saksida, T; Vujicic, M; Nikolic, I; Stojanovic, I; Haegeman, G; Stosic-Grujicic, S

    2014-01-01

    Background and Purpose Type 1 diabetes is a multifactorial inflammatory disease that develops as a result of deregulated immune responses, causing progressive autoimmune destruction of insulin-producing beta cells of pancreas. 2-((4-acetoxyphenyl)-2-chloro-N-methyl) ethylammonium chloride, compound A (CpdA), is a selective glucocorticoid receptor (GR) agonist that displays strong anti-inflammatory and immunomodulatory activities. We investigated the therapeutic effectiveness of CpdA in a pharmacological model of type 1 diabetes in mice. Experimental Approach The utility of CpdA in diabetes prevention was evaluated in vivo through its prophylactic administration to male C57BL/6 mice that received multiple low doses of streptozotocin for immunoinflammatory diabetes induction. The effect of CpdA on disease development was studied by measuring blood glucose and insulin level, histopathological examination, determination of the nature of infiltrating cells, pro- and anti-inflammatory cytokine production, and signalling pathways. Key Results Prophylactic in vivo therapy with CpdA conferred protection against development of immunoinflammatory diabetes in mice by dampening the M1/Th1/Th17 immune response and switching it towards an anti-inflammatory M2/Th2/Treg profile, thus preserving beta cell function. Conclusions and Implications Anti-diabetic properties of CpdA are mediated through modulation of immune cell-mediated pathways, but without triggering adverse events. These findings provide basic information for the therapeutic use of selective GR agonists in the amelioration of islet-directed autoimmunity. PMID:25158597

  19. Acute systemic 11-cis-retinal intervention improves abnormal outer retinal ion channel closure in diabetic mice

    PubMed Central

    Bissig, David; Patel, Priya; Bhatia, Ankit; Roberts, Robin

    2012-01-01

    Purpose To test the hypothesis that in dark-adapted diabetic mice subnormal manganese uptake in the outer retina can be ameliorated with exogenous 11-cis-retinal intervention. Methods Three groups were studied: age-matched controls and mice that had been diabetic for 3 months with and without acute, systemic 11-cis-retinal treatment administered 30 min before the manganese injection. Mice in each group were examined with manganese-enhanced magnetic resonance imaging (MEMRI) to assess central intraretinal manganese uptake and extraocular muscle manganese uptake. Bodyweights and glycated hemoglobin were determined. Results Both diabetic groups had lower bodyweights and higher glycated hemoglobin levels relative to controls; no differences in these parameters between diabetic groups were noted. No substantial differences in muscle uptake were noted between any of the groups. Diabetes produced a subnormal intraretinal uptake of manganese; acute exogenous 11-cis-retinal significantly corrected only outer retinal uptake, although not to control levels. Conclusions The present results provide for the first time evidence that raises the possibility of a critical role of 11-cis-retinal, a key participant of the visual cycle, in diabetes-evoked outer retinal dysfunction. PMID:22355248

  20. A modest decrease in endothelial NOS in mice comparable to that associated with human NOS3 variants exacerbates diabetic nephropathy

    PubMed Central

    Wang, Chih-Hong; Li, Feng; Hiller, Sylvia; Kim, Hyung-Suk; Maeda, Nobuyo; Smithies, Oliver; Takahashi, Nobuyuki

    2011-01-01

    Polymorphisms in the human endothelial nitric oxide synthase (eNOS) gene (NOS3) have been associated with advanced nephropathy in diabetic patients and with decreased expression in tissue culture. However, direct proof that modest genetic decreases in eNOS expression worsen diabetic nephropathy is lacking. To investigate this effect, we took advantage of the hybrid vigor and genetic uniformity of the F1 progeny (eNOS+/+, eNOS+/?, or eNOS?/? with or without diabetes) of a cross between heterozygous 129S6/SvEvTac eNOS+/? inbred females and heterozygous C57BL/6J eNOS+/? inbred males carrying the dominant Akita diabetogenic mutation Ins2C96Y/+. Whereas all C57BL/6J inbred eNOS?/? and eNOS+/? diabetic mice died before 5 mo, almost half of the F1 hybrid eNOS?/? and eNOS+/? diabetic mice lived until killed at 7 mo. Heterozygous eNOS+/? diabetic mice expressed ?35% eNOS mRNA in the kidney and ?25% glomerular eNOS protein relative to their eNOS+/+ diabetic littermates. These decreases in eNOS elevated blood pressure (BP) but not blood glucose. Urinary albumin excretion, mesangial expansion, glomerulosclerosis, mesangiolysis, and glomerular filtration rate increased in the order: eNOS+/+ Akita < eNOS+/? Akita < eNOS?/? Akita, independently of BP. Glomerular basement membrane thickening depended on increased BP. Renal expression of tissue factor and other inflammatory factors increased with the nephropathy; Nos2 also increased. Surprisingly, however, decreased eNOS expression ameliorated the increases in oxidative stress and tubulointerstitial fibrosis caused by diabetes. Our data demonstrate that a modest decrease in eNOS, comparable to that associated with human NOS3 variants, is sufficient to enhance diabetic nephropathy independently of its effects on BP. PMID:21245338

  1. Astragaloside effect on TGF-?1, SMAD2/3, and ?-SMA expression in the kidney tissues of diabetic KKAy mice

    PubMed Central

    Wang, Yaning; Lin, Chao; Ren, Qiang; Liu, Yunqi; Yang, Xiangdong

    2015-01-01

    Numerous cytokines participate in the occurrence and development of inflammation and renal interstitial fibrosis. Previous studies confirmed that TGF-?1 overexpressed in diabetic nephropathy. As a downstream signal protein of TGF-?1 family, SMAD has an important role in the process of ?-SMA mediated renal interstitial fibrosis. This study aimed to study astragaloside effect on TGF-?1, SMAD2/3, and ?-SMA expression in the kidney tissue of diabetic KKAy mice, to reveal its potential impact on renal interstitial fibrosis. 20 type II diabetic KKAy mice were randomly equally divided into model group and astragaloside group, while 10 male C57BL/6J mice were selected as the control. Astragaloside at 40 mg/(kg•d) was given when the KKAy mice fed with high-fat diet to 14 weeks old. The mice were killed at 24 weeks old and the kidney tissue samples were collected. Pathology morphological changes were observed. TGF-?1, SMAD2/3, and ?-SMA expression levels were determined by immunohistochemistry. Compared with control, mice kidney in model group appeared obvious fibrosis and up-regulated blood glucose level, TGF-?1, SMAD2/3, and ?-SMA expression (P < 0.05). Mice in astragaloside group exhibited alleviated renal interstitial fibrosis compared with the model. Its blood glucose level, TGF-?1, SMAD2/3, and ?-SMA expression levels were significantly lower than the model group (P < 0.05). Astragaloside can delay the renal fibrosis process in diabetic mice by influencing the TGF-?/SMADS signaling pathway and down-regulating TGF-?1, SMAD2/3, and ?-SMA expression. PMID:26261569

  2. Protective Effect of Topiramate on Hyperglycemia-Induced Cerebral Oxidative Stress, Pericyte Loss and Learning Behavior in Diabetic Mice

    PubMed Central

    Price, Tulin O.; Farr, Susan A.; Niehoff, Michael L.; Ercal, Nuran; Morley, John E.; Shah, Gul N.

    2015-01-01

    Diabetes mellitus-associated damage to the microvasculature of the brain is caused by hyperglycemia-induced oxidative stress, which results in pericyte loss, blood-brain barrier disruption, and impaired cognitive function. Oxidative stress, in diabetes, is caused by reactive oxygen species produced during accelerated respiration (mitochondrial oxidative metabolism of glucose). The rate of respiration is regulated by mitochondrial carbonic anhydrases (CAs). Inhibition of these enzymes protects the brain from diabetic damage. Previously, we reported that topiramate, a mitochondrial CA inhibitor, at a dose of 50 mg/kg/day protects the brain in diabetes by reducing oxidative stress and restoring pericyte numbers. Topiramate has high affinity for both mitochondrial CAs; therefore, it is conceivable that a much lower dose may inhibit these enzymes and thus protect the brain from hyperglycemia-induced oxidative damage. Therefore, in an effort to reduce the toxicity associated with higher doses of topiramate, the current study was designed to investigate the effect of 1.0 mg/kg topiramate on reducing oxidative stress, restoring pericyte numbers in the brain, and improving the impaired learning behavior in diabetic mouse. Diabetes was induced by a one-time injection of streptozotocin and topiramate was administered daily for 12 weeks. Levels of oxidative stress, reduced glutathione (GSH) and 4-hydroxy-2-trans-nonenal (HNE) were measured in the brain and pericyte/endothelial cell ratios in isolated brain microvessels. Learning behavior was assessed by T-maze foot shock avoidance test. A significant decrease in GSH (control, 12.2 ± 0.4 vs. diabetic, 10.8 ± 0.4 vs. diabetic + topiramate, 12.6 ± 0.6, p<0.05) and an increase in HNE (control, 100 ± 4.2, vs. diabetic, 127.3 ± 8.8 vs. diabetic + topiramate, 93.9 ± 8.4 p<0.05) in diabetic mice were corrected by topiramate treatment. Topiramate treatment also resulted in restoration of pericyte numbers in diabetic mice (control, 25.89 ± 0.85 vs. diabetic, 18.14 ± 0.66 vs. diabetic + topiramate, 24.35 ± 0.53, p<0.001) and improvement in learning behavior. In conclusion, these data clearly demonstrate that topiramate at 1.0 mg/kg protects the mouse brain from diabetic damage. A 1.0 mg/kg topiramate in the mouse translates to a 5.0 mg daily dose in a 60 kg human, which may help slow the onset and progression of diabetic complications in the human brain. PMID:26120599

  3. Brugia malayi soluble and excretory-secretory proteins attenuate development of streptozotocin-induced type 1 diabetes in mice.

    PubMed

    Amdare, N; Khatri, V; Yadav, R S P; Tarnekar, A; Goswami, K; Reddy, M V R

    2015-12-01

    Understanding the modulation of the host-immune system by pathogens-like filarial parasites offers an alternate approach to prevent autoimmune diseases. In this study, we have shown that treatment with filarial proteins prior to or after the clinical onset of streptozotocin-induced type-1 diabetes (T1D) can ameliorate the severity of disease in BALB/c mice. Pre-treatment with Brugia malayi adult soluble (Bm A S) or microfilarial excretory-secretory (Bm mf ES) or microfilarial soluble (Bm mf S) antigens followed by induction of diabetes led to lowering of fasting blood glucose levels with as many as 57·5-62·5% of mice remaining nondiabetic. These proteins were more effective when they were used to treat the mice with established T1D as 62·5-71·5% of the mice turned to be nondiabetic. Histopathological examination of pancreas of treated mice showed minor inflammatory changes in pancreatic islet cell architecture. The therapeutic effect was found to be associated with the decreased production of cytokines TNF-? & IFN-? and increased production of IL-10 in the culture supernatants of splenocytes of treated mice. A switch in the production of anti-insulin antibodies from IgG2a to IgG1 isotype was also seen. Together these results provide a proof towards utilizing the filarial derived proteins as novel anti-diabetic therapeutics. PMID:26434489

  4. BBT improves glucose homeostasis by ameliorating ?-cell dysfunction in type 2 diabetic mice.

    PubMed

    Yao, Xin-gang; Xu, Xin; Wang, Gai-hong; Lei, Min; Quan, Ling-ling; Cheng, Yan-hua; Wan, Ping; Zhou, Jin-pei; Chen, Jing; Hu, Li-hong; Shen, Xu

    2015-03-01

    Impaired glucose-stimulated insulin secretion (GSIS) and increasing ?-cell death are two typical dysfunctions of pancreatic ?-cells in individuals that are destined to develop type 2 diabetes, and improvement of ?-cell function through GSIS enhancement and/or inhibition of ?-cell death is a promising strategy for anti-diabetic therapy. In this study, we discovered that the small molecule, N-(2-benzoylphenyl)-5-bromo-2-thiophenecarboxamide (BBT), was effective in both potentiating GSIS and protecting ?-cells from cytokine- or streptozotocin (STZ)-induced cell death. Results of further studies revealed that cAMP/PKA and long-lasting (L-type) voltage-dependent Ca(2) (+) channel/CaMK2 pathways were involved in the action of BBT against GSIS, and that the cAMP/PKA pathway was essential for the protective action of BBT on ?-cells. An assay using the model of type 2 diabetic mice induced by high-fat diet combined with STZ (STZ/HFD) demonstrated that BBT administration efficiently restored ?-cell functions as indicated by the increased plasma insulin level and decrease in the ?-cell loss induced by STZ/HFD. Moreover, the results indicated that BBT treatment decreased fasting blood glucose and HbA1c and improved oral glucose tolerance further highlighting the potential of BBT in anti-hyperglycemia research. PMID:25572265

  5. A CD40-targeted peptide controls and reverses type 1 diabetes in NOD mice

    PubMed Central

    Vaitaitis, Gisela M.; Olmstead, Michael H.; Waid, Dan M.; Carter, Jessica R.; Wagner, David H.

    2014-01-01

    Aims/Hypothesis The CD40–CD154 interaction directs autoimmune inflammation. Therefore, a longstanding goal in the treatment of autoimmune disease has been to control the formation of that interaction and thereby prevent destructive inflammation. Antibodies blocking CD154 are successful in mouse models of autoimmune disease but, while promising when used in humans, unfortunate thrombotic events have occurred, forcing the termination of those studies. Methods To address the clinical problem of thrombotic events caused by anti-CD154 antibody treatment, we created a series of small peptides based on the CD154 domain that interacts with CD40 and tested the ability of these peptides to target CD40 and prevent type 1 diabetes in NOD mice. Results We identified a lead candidate, the 15-mer KGYY15 peptide, which specifically targets CD40-positive cells in a size- and sequence-dependent manner. It is highly efficient in preventing hyperglycaemia in NOD mice that spontaneously develop type 1 diabetes. Importantly, KGYY15 can also reverse new-onset hyperglycaemia. KGYY15 is well tolerated and functions to control the cytokine profile of culprit Th40 effector T cells. The KGYY15 peptide is 87% homologous to the human sequence, suggesting that it is an important candidate for translational studies. Conclusions Peptide KGYY15 constitutes a viable therapeutic option to antibody therapy in targeting the CD40–CD154 interaction in type 1 diabetes. Given the involvement of CD40 in autoimmunity in general, it will also be important to evaluate KGYY15 in the treatment of other autoimmune diseases. This alternative therapeutic approach opens new avenues of exploration in targeting receptor–ligand interactions. PMID:25104468

  6. Identification of a novel gene for diabetic traits in rats, mice, and humans.

    PubMed

    Tsaih, Shirng-Wern; Holl, Katie; Jia, Shuang; Kaldunski, Mary; Tschannen, Michael; He, Hong; Andrae, Jaime Wendt; Li, Shun-Hua; Stoddard, Alex; Wiederhold, Andrew; Parrington, John; Ruas da Silva, Margarida; Galione, Antony; Meigs, James; Hoffmann, Raymond G; Simpson, Pippa; Jacob, Howard; Hessner, Martin; Solberg Woods, Leah C

    2014-09-01

    The genetic basis of type 2 diabetes remains incompletely defined despite the use of multiple genetic strategies. Multiparental populations such as heterogeneous stocks (HS) facilitate gene discovery by allowing fine mapping to only a few megabases, significantly decreasing the number of potential candidate genes compared to traditional mapping strategies. In the present work, we employed expression and sequence analysis in HS rats (Rattus norvegicus) to identify Tpcn2 as a likely causal gene underlying a 3.1-Mb locus for glucose and insulin levels. Global gene expression analysis on liver identified Tpcn2 as the only gene in the region that is differentially expressed between HS rats with glucose intolerance and those with normal glucose regulation. Tpcn2 also maps as a cis-regulating expression QTL and is negatively correlated with fasting glucose levels. We used founder sequence to identify variants within this region and assessed association between 18 variants and diabetic traits by conducting a mixed-model analysis, accounting for the complex family structure of the HS. We found that two variants were significantly associated with fasting glucose levels, including a nonsynonymous coding variant within Tpcn2. Studies in Tpcn2 knockout mice demonstrated a significant decrease in fasting glucose levels and insulin response to a glucose challenge relative to those in wild-type mice. Finally, we identified variants within Tpcn2 that are associated with fasting insulin in humans. These studies indicate that Tpcn2 is a likely causal gene that may play a role in human diabetes and demonstrate the utility of multiparental populations for positionally cloning genes within complex loci. PMID:25236446

  7. Lentivectors encoding immunosuppressive proteins genetically engineer pancreatic beta-cells to correct diabetes in allogeneic mice.

    PubMed

    Kojaoghlanian, T; Joseph, A; Follenzi, A; Zheng, J H; Leiser, M; Fleischer, N; Horwitz, M S; DiLorenzo, T P; Goldstein, H

    2009-03-01

    The effectiveness of genetic engineering with lentivectors to protect transplanted cells from allogeneic rejection was examined using, as a model, type 1 diabetes treatment with beta-cell transplantation, whose widespread use has been limited by the requirement for sustained immunosuppressive treatment to prevent graft rejection. We examined whether lentivectors expressing select immunosuppressive proteins encoded by the adenoviral genome early region 3 (AdE3) would protect transplanted beta-cells from an alloimmune attack. The insulin-producing beta-cell line beta TC-tet (C3HeB/FeJ-derived) was transduced with lentiviruses encoding the AdE3 proteins gp19K and RID alpha/beta. The efficiency of lentiviral transduction of beta TC-tet cells exceeded 85%. Lentivector expression of gp19K decreased surface class I major histocompatibility complex expression by over 90%, whereas RID alpha/beta expression inhibited cytokine-induced Fas upregulation by over 75%. beta TC-tet cells transduced with gp19K and RID alpha/beta lentivectors, but not with a control lentivector, provided prolonged correction of hyperglycemia after transplantation into diabetic BALB/c severe combined immunodeficient mice reconstituted with allogeneic immune effector cells or into diabetic allogeneic BALB/c mice. Thus, genetic engineering of beta-cells using gp19K- and RID alpha/beta-expressing lentiviral vectors may provide an alternative that has the potential to eliminate or reduce treatment with the potent immunosuppressive agents necessary at present for prolonged engraftment with transplanted islets. PMID:19112449

  8. Anti-diabetic effect of purple corn extract on C57BL/KsJ db/db mice

    PubMed Central

    Huang, Bo; Wang, Zhiqiang; Park, Jong Hyuk; Ryu, Ok Hyun; Choi, Moon Ki; Lee, Jae-Yong; Kang, Young-Hee

    2015-01-01

    BACKGROUND/OBJECTIVES Recently, anthocyanins have been reported to have various biological activities. Furthermore, anthocyanin-rich purple corn extract (PCE) ameliorated insulin resistance and reduced diabetes-associated mesanginal fibrosis and inflammation, suggesting that it may have benefits for the prevention of diabetes and diabetes complications. In this study, we determined the anthocyanins and non-anthocyanin component of PCE by HPLC-ESI-MS and investigated its anti-diabetic activity and mechanisms using C57BL/KsJ db/db mice. MATERIALS/METHODS The db/db mice were divided into four groups: diabetic control group (DC), 10 or 50 mg/kg PCE (PCE 10 or PCE 50), or 10 mg/kg pinitol (pinitol 10) and treated with drugs once per day for 8 weeks. During the experiment, body weight and blood glucose levels were measured every week. At the end of treatment, we measured several diabetic parameters. RESULTS Compared to the DC group, Fasting blood glucose levels were 68% lower in PCE 50 group and 51% lower in the pinitol 10 group. Furthermore, the PCE 50 group showed 2- fold increased C-peptide and adiponectin levels and 20% decreased HbA1c levels, than in the DC group. In pancreatic islets morphology, the PCE- or pinitol-treated mice showed significant prevention of pancreatic ?-cell damage and higher insulin content. Microarray analyses results indicating that gene and protein expressions associated with glycolysis and fatty acid metabolism in liver and fat tissues. In addition, purple corn extract increased the phosphorylation of AMP-activated protein kinase (AMPK) and decreased phosphoenolpyruvate carboxykinase (PEPCK), glucose 6-phosphatase (G6pase) genes in liver, and also increased glucose transporter 4 (GLUT4) expressions in skeletal muscle. CONCLUSIONS Our results suggested that PCE exerted anti-diabetic effects through protection of pancreatic ?-cells, increase of insulin secretion and AMPK activation in the liver of C57BL/KsJ db/db mice. PMID:25671064

  9. Differential proteomic analysis of the pancreas of diabetic db/db mice reveals the proteins involved in the development of complications of diabetes mellitus.

    PubMed

    Pérez-Vázquez, Victoriano; Guzmán-Flores, Juan M; Mares-Álvarez, Daniela; Hernández-Ortiz, Magdalena; Macías-Cervantes, Maciste H; Ramírez-Emiliano, Joel; Encarnación-Guevara, Sergio

    2014-01-01

    Type 2 diabetes mellitus is characterized by hyperglycemia and insulin-resistance. Diabetes results from pancreatic inability to secrete the insulin needed to overcome this resistance. We analyzed the protein profile from the pancreas of ten-week old diabetic db/db and wild type mice through proteomics. Pancreatic proteins were separated in two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and significant changes in db/db mice respect to wild type mice were observed in 27 proteins. Twenty five proteins were identified by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) and their interactions were analyzed using search tool for the retrieval of interacting genes/proteins (STRING) and database for annotation, visualization and integrated discovery (DAVID). Some of these proteins were Pancreatic ?-amylase, Cytochrome b5, Lithostathine-1, Lithostathine-2, Chymotrypsinogen B, Peroxiredoxin-4, Aspartyl aminopeptidase, Endoplasmin, and others, which are involved in the metabolism of carbohydrates and proteins, as well as in oxidative stress, and inflammation. Remarkably, these are mostly endoplasmic reticulum proteins related to peptidase activity, i.e., they are involved in proteolysis, glucose catabolism and in the tumor necrosis factor-mediated signaling pathway. These results suggest mechanisms for insulin resistance, and the chronic inflammatory state observed in diabetes. PMID:24886809

  10. Novel small-molecule AMPK activator orally exerts beneficial effects on diabetic db/db mice

    SciTech Connect

    Li, Yuan-Yuan; Yu, Li-Fang; Zhang, Li-Na; Qiu, Bei-Ying; Su, Ming-Bo; Wu, Fang; Chen, Da-Kai; Pang, Tao; Gu, Min; Zhang, Wei; Ma, Wei-Ping; Jiang, Hao-Wen; Li, Jing-Ya Nan, Fa-Jun Li, Jia

    2013-12-01

    AMP-activated protein kinase (AMPK), which is a pivotal guardian of whole-body energy metabolism, has become an attractive therapeutic target for metabolic syndrome. Previously, using a homogeneous scintillation proximity assay, we identified the small-molecule AMPK activator C24 from an optimization based on the original allosteric activator PT1. In this paper, the AMPK activation mechanism of C24 and its potential beneficial effects on glucose and lipid metabolism on db/db mice were investigated. C24 allosterically stimulated inactive AMPK ? subunit truncations and activated AMPK heterotrimers by antagonizing autoinhibition. In primary hepatocytes, C24 increased the phosphorylation of AMPK downstream target acetyl-CoA carboxylase dose-dependently without changing intracellular AMP/ATP ratio, indicating its allosteric activation in cells. Through activating AMPK, C24 decreased glucose output by down-regulating mRNA levels of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) in primary hepatocytes. C24 also decreased the triglyceride and cholesterol contents in HepG2 cells. Due to its improved bioavailability, chronic oral treatment with multiple doses of C24 significantly reduced blood glucose and lipid levels in plasma, and improved the glucose tolerance of diabetic db/db mice. The hepatic transcriptional levels of PEPCK and G6Pase were reduced. These results demonstrate that this orally effective activator of AMPK represents a novel approach to the treatment of metabolic syndrome. - Highlights: • C24 activates AMPK through antagonizing autoinhibition within ? subunit. • C24 activates AMPK in hepatocytes and decreases glucose output via AMPK. • C24 exerts beneficial effects on diabetic db/db mice. • C24 represents a novel therapeutic for treatment of metabolic syndrome.

  11. A mixture of extracts from Peruvian plants (black maca and yacon) improves sperm count and reduced glycemia in mice with streptozotocin-induced diabetes.

    PubMed

    Gonzales, Gustavo F; Gonzales-Castañeda, Cynthia; Gasco, Manuel

    2013-09-01

    We investigated the effect of two extracts from Peruvian plants given alone or in a mixture on sperm count and glycemia in streptozotocin-diabetic mice. Normal or diabetic mice were divided in groups receiving vehicle, black maca (Lepidium meyenii), yacon (Smallanthus sonchifolius) or three mixtures of extracts black maca/yacon (90/10, 50/50 and 10/90%). Normal or diabetic mice were treated for 7?d with each extract, mixture or vehicle. Glycemia, daily sperm production (DSP), epididymal and vas deferens sperm counts in mice and polyphenol content, and antioxidant activity in each extract were assessed. Black maca (BM), yacon and the mixture of extracts reduced glucose levels in diabetic mice. Non-diabetic mice treated with BM and yacon showed higher DSP than those treated with vehicle (p?Diabetic mice treated with BM, yacon and the mixture maca/yacon increased DSP, and sperm count in vas deferens and epididymis with respect to non-diabetic and diabetic mice treated with vehicle (p?diabetic mice. Streptozotocin increased 1.43 times the liver weight that was reversed with the assessed plants extracts. In summary, streptozotocin-induced diabetes resulted in reduction in sperm counts and liver damage. These effects could be reduced with BM, yacon and the BM+yacon mixture. PMID:23489070

  12. Differential expression of protein kinase C isoforms in coronary arteries of diabetic mice lacking the G-protein G?11

    PubMed Central

    2010-01-01

    Background Diabetes mellitus counts as a major risk factor for developing atherosclerosis. The activation of protein kinase C (PKC) is commonly known to take a pivotal part in the pathogenesis of atherosclerosis, though the influence of specific PKC isozymes remains unclear. There is evidence from large clinical trials suggesting excessive neurohumoral stimulation, amongst other pathways leading to PKC activation, as a central mechanism in the pathogenesis of diabetic heart disease. The present study was therefore designed to determine the role of Gq-protein signalling via G?11 in diabetes for the expression of PKC isozymes in the coronary vessels. Methods The role of G?11 in diabetes was examined in knockout mice with global deletion of G?11 compared to wildtype controls. An experimental type 1-diabetes was induced in both groups by injection of streptozotocin. Expression and localization of the PKC isozymes ?, ?II, ?, ?, and ? was examined by quantitative immunohistochemistry. Results 8 weeks after induction of diabetes a diminished expression of PKC ? was observed in wildtype animals. This alteration was not seen in G?11 knockout animals, however, these mice showed a diminished expression of PKC?. Direct comparison of wildtype and knockout control animals revealed a diminished expression of PKC ? and ? in G?11 knockout animals. Conclusion The present study shows that expression of the nPKCs ? and ? in coronary vessels is under control of the g-protein G?11. The reduced expression of PKC ? that we observed in coronary arteries from G?11-knockout mice compared to wildtype controls upon induction of diabetes could reduce apoptosis and promote plaque stability. These findings suggest a mechanism that may in part underlie the therapeutic benefit of RAS inhibition on cardiovascular endpoints in diabetic patients. PMID:21190563

  13. Angiotensin I–Converting Enzyme Type 2 (ACE2) Gene Therapy Improves Glycemic Control in Diabetic Mice

    PubMed Central

    Bindom, Sharell M.; Hans, Chetan P.; Xia, Huijing; Boulares, A. Hamid; Lazartigues, Eric

    2010-01-01

    OBJECTIVE Several clinical studies have shown the benefits of renin-angiotensin system (RAS) blockade in the development of diabetes, and a local RAS has been identified in pancreatic islets. Angiotensin I–converting enzyme (ACE)2, a new component of the RAS, has been identified in the pancreas, but its role in ?-cell function remains unknown. Using 8- and 16-week-old obese db/db mice, we examined the ability of ACE2 to alter pancreatic ?-cell function and thereby modulate hyperglycemia. RESEARCH DESIGN AND METHODS Both db/db and nondiabetic lean control (db/m) mice were infected with an adenovirus expressing human ACE2 (Ad-hACE2-eGFP) or the control virus (Ad-eGFP) via injection into the pancreas. Glycemia and ?-cell function were assessed 1 week later at the peak of viral expression. RESULTS In 8-week-old db/db mice, Ad-hACE2-eGFP significantly improved fasting glycemia, enhanced intraperitoneal glucose tolerance, increased islet insulin content and ?-cell proliferation, and reduced ?-cell apoptosis compared with Ad-eGFP. ACE2 overexpression had no effect on insulin sensitivity in comparison with Ad-eGFP treatment in diabetic mice. Angiotensin-(1–7) receptor blockade by d-Ala7–Ang-(1-7) prevented the ACE2-mediated improvements in intraperitoneal glucose tolerance, glycemia, and islet function and also impaired insulin sensitivity in both Ad-hACE2-eGFP– and Ad-eGFP–treated db/db mice. d-Ala7–Ang-(1-7) had no effect on db/m mice. In 16-week-old diabetic mice, Ad-hACE2-eGFP treatment improved fasting blood glucose but had no effect on any of the other parameters. CONCLUSIONS These findings identify ACE2 as a novel target for the prevention of ?-cell dysfunction and apoptosis occurring in type 2 diabetes. PMID:20660625

  14. Caloric restriction and intermittent fasting alter hepatic lipid droplet proteome and diacylglycerol species and prevent diabetes in NZO mice.

    PubMed

    Baumeier, Christian; Kaiser, Daniel; Heeren, Jörg; Scheja, Ludger; John, Clara; Weise, Christoph; Eravci, Murat; Lagerpusch, Merit; Schulze, Gunnar; Joost, Hans-Georg; Schwenk, Robert Wolfgang; Schürmann, Annette

    2015-05-01

    Caloric restriction and intermittent fasting are known to improve glucose homeostasis and insulin resistance in several species including humans. The aim of this study was to unravel potential mechanisms by which these interventions improve insulin sensitivity and protect from type 2 diabetes. Diabetes-susceptible New Zealand Obese mice were either 10% calorie restricted (CR) or fasted every other day (IF), and compared to ad libitum (AL) fed control mice. AL mice showed a diabetes prevalence of 43%, whereas mice under CR and IF were completely protected against hyperglycemia. Proteomic analysis of hepatic lipid droplets revealed significantly higher levels of PSMD9 (co-activator Bridge-1), MIF (macrophage migration inhibitor factor), TCEB2 (transcription elongation factor B (SIII), polypeptide 2), ACY1 (aminoacylase 1) and FABP5 (fatty acid binding protein 5), and a marked reduction of GSTA3 (glutathione S-transferase alpha 3) in samples of CR and IF mice. In addition, accumulation of diacylglycerols (DAGs) was significantly reduced in livers of IF mice (P=0.045) while CR mice showed a similar tendency (P=0.062). In particular, 9 DAG species were significantly reduced in response to IF, of which DAG-40:4 and DAG-40:7 also showed significant effects after CR. This was associated with a decreased PKC? activation and might explain the improved insulin sensitivity. In conclusion, our data indicate that protection against diabetes upon caloric restriction and intermittent fasting associates with a modulation of lipid droplet protein composition and reduction of intracellular DAG species. PMID:25645620

  15. Effect of Cnidoscolus aconitifolius leaf extract on the blood glucose and insulin levels of inbred type 2 diabetic mice.

    PubMed

    Oladeinde, F O; Kinyua, A M; Laditan, A A; Michelin, R; Bryant, J L; Denaro, F; Makinde, J M; Williams, A L; Kennedy, A P; Bronner, Y

    2007-01-01

    The effects of Cnidoscolus aconitifolius (CA) leaf extract and chlorpropamide on blood glucose and insulin levels in the inbred type 2 diabetic mice are reported. After treatment with CA, the glucose levels were measured at 0 and 2-hour intervals in experimental groups and controls. Group I received no treatment and served as control; Group II was the reference and it received chlorpropamide; Groups I-III were moderately diabetic, 100-300 mg/dL blood glucose levels while Group IV were severely diabetic (> 300 mg/dL). Groups III and IV received CA and served as test groups. There was no significant difference between the blood glucose levels at 0 and 2 hours for the control group, (P>0.23) but there were statistically significant differences for Group II (P<0.0002); Group III (P<0.002) and Group IV (P<0.0001). For moderately diabetic mice, CA and chlorpropamide decreased the glucose levels by 25.6% and 16.3% respectively while for the severely diabetic mice CA decreased the blood glucose by 43.7%. It is proposed that CA has an insulinogenic property that possibly stimulated dormant beta-cells to secrete insulin. The histopathology of several organs in the treated animals was found to differ from the expected. The islets of Langerhans for example were found to be preserved in the time frame examined. Also the liver and kidney were found to display milder pathology in the treated groups. PMID:17531147

  16. In Vivo Hypoglycaemic Effect and Inhibitory Mechanism of the Branch Bark Extract of the Mulberry on STZ-Induced Diabetic Mice

    PubMed Central

    Liu, Hua-Yu; Fang, Meng; Zhang, Yu-Qing

    2014-01-01

    Branch bark extract (BBE) derived from the mulberry cultivar Husang 32 (Morus multicaulis L.) with aqueous alcohol solution has been investigated as an inhibitor of ?-glycosidase in vitro. Mulberry BBE was orally administered to STZ-induced diabetic mice for three weeks, and it improved the weight gain and ameliorated the swelling of liver and kidney in diabetic mice. Obviously, mulberry BBE not only can reduce the abnormally elevated levels of serum insulin and ameliorate insulin resistance induced by STZ, but also it regulates dyslipidemia in diabetic mice. To understand this therapeutic effect and the regulatory mechanisms of BBE in diabetic mice, a qRT-PCR experiment was performed, indicating that the mulberry BBE can regulate the mRNA expression of glycometabolism genes in diabetic mice, including glucose-6-phosphatase (G6Pase), glucokinase (GCK), and phosphoenolpyruvate carboxykinase (PEPCK), thereby regulating sugar metabolism and reducing the blood glucose level in diabetic mice. The mulberry BBE can increase the mRNA expression of the genes Ins1, Ins2 and pancreatic duodenal homeobox-1 (PDX-1) and may decrease the insulin resistance in diabetic mice. Those results provide an important basis for making the best use of mulberry branch resources and producing biomedical drugs with added value. PMID:25177729

  17. Investigation on the hypoglycaemic effects of extracts of four Mexican medicinal plants in normal and alloxan-diabetic mice.

    PubMed

    Alarcon-Aguilar, F J; Roman-Ramos, R; Flores-Saenz, J L; Aguirre-Garcia, F

    2002-06-01

    The hypoglycaemic activities of four water ethanol extracts (WEE) prepared from Bidens pilosa L., Salvia officinalis L., Psacalium peltatum H.B.K. (Cass) and Turnera diffusa Willd. were investigated in healthy and alloxan-diabetic mice. The WEE of S. officinalis significantly reduced the blood glucose of fasting normal mice 120 (15.7%) and 240 min (30.2%) after intraperitoneal administration (p < 0.05). The WEE of P. peltatum and B. pilosa also significantly diminished glycaemia in healthy mice at 240 min (19.6% and 13.8%, respectively). In mildly diabetic mice, the WEE of P. peltatum lowered the basal blood glucose level 120 (16%) and 240 min (54%) after intraperitoneal administration (p < 0.05 and p < 0.01, respectively). The WEE of B. pilosa and S. officinalis also significantly diminished the hyperglycaemia in mildly diabetic mice at 240 mins (32.6% and 22.7%, respectively). The administration of these three extracts to animals with severe hyperglycaemia did not cause a significant decrease. The WEE of T. diffusa did not show any hypoglycaemic activity. Thus, three of the WEE studied conserved the hypoglycaemic activity originally detected in the traditional preparations of the studied antidiabetic plants. It appears that these extracts require the presence of insulin to show hypoglycaemic activity. PMID:12112298

  18. High insulin levels in KK-Ay diabetic mice cause increased cortical bone mass and impaired trabecular micro-structure.

    PubMed

    Fu, Cen; Zhang, Xiaolin; Ye, Fei; Yang, Jianhong

    2015-01-01

    Type 2 diabetes mellitus (T2DM) is a chronic disease characterized by hyperglycemia, hyperinsulinemia and complications, including obesity and osteoporosis. Rodents have been widely used to model human T2DM and investigate its effect on the skeleton. We aimed to investigate skeletal alterations in Yellow Kuo Kondo (KK-Ay) diabetic mice displaying high insulin and glucose levels. Bone mineral density (BMD), micro-architecture and bone metabolism-related genes were analyzed. The total femoral areal BMD (aBMD), cortical volumetric BMD (vBMD) and thickness were significantly increased in KK-Ay mice, while the trabecular vBMD and mineralized bone volume/tissue volume (BV/TV), trabecular thickness and number were decreased compared to C57BL mice. The expression of both osteoblast-related genes, such as osteocalcin (OC), bone sialoprotein, Type I Collagen, osteonectin, RUNX2 and OSX, and osteoclast-related genes, such as TRAP and TCIRG, were up-regulated in KK-Ay mice. Correlation analyses showed that serum insulin levels were positively associated with aBMD, cortical vBMD and thickness and negatively associated with trabecular vBMD and micro-architecture. In addition, serum insulin levels were positively related to osteoblast-related and osteoclast-related gene expression. Our data suggest that high insulin levels in KK-Ay diabetic mice may increase cortical bone mass and impair trabecular micro-structure by up-regulating osteoblast-and osteoclast-related gene expression. PMID:25872143

  19. Diabetes susceptibility of BALB/cBOM mice treated with streptozotocin. Inhibition by lethal irradiation and restoration by splenic lymphocytes

    SciTech Connect

    Paik, S.G.; Blue, M.L.; Fleischer, N.; Shin, S.

    1982-09-01

    In genetically susceptible strains of mice, repeated injections of a subdiabetogenic dose of streptozotocin induces the development of progressive insulin-dependent hyperglycemia. We showed previously that host T-cell functions play an obligatory etiologic role in this experimental disease by demonstrating that the athymic nude mouse is resistant to diabetes induction unless its T-cell functions are reconstituted by thymus graft. Here we show that lethal irradiation of euthymic (+/nu) mice of BALB/cBOM background causes selective resistance of the mice to the diabetogenic effects of the multiple low doses of streptozotocin without affecting their sensitivity to a high pharmacologic dose of the toxin. We also show that reconstitution of the irradiated mice with splenic lymphocytes causes the restoration of diabetes susceptibility. Lethally irradiated mice thus represent a useful experimental model for analyzing the host functions involved in the development of this disease. These results provide an additional support for the hypothesis that the induction of diabetes in this model system is mediated by an autoimmune amplification mechanism.

  20. Decellularized silk fibroin scaffold primed with adipose mesenchymal stromal cells improves wound healing in diabetic mice

    PubMed Central

    2014-01-01

    Introduction Silk fibroin (SF) scaffolds have been shown to be a suitable substrate for tissue engineering and to improve tissue regeneration when cellularized with mesenchymal stromal cells (MSCs). We here demonstrate, for the first time, that electrospun nanofibrous SF patches cellularized with human adipose-derived MSCs (Ad-MSCs-SF), or decellularized (D-Ad-MSCs-SF), are effective in the treatment of skin wounds, improving skin regeneration in db/db diabetic mice. Methods The conformational and structural analyses of SF and D-Ad-MSCs-SF patches were performed by scanning electron microscopy, confocal microscopy, Fourier transform infrared spectroscopy and differential scanning calorimetry. Wounds were performed by a 5 mm punch biopsy tool on the mouse’s back. Ad-MSCs-SF and D-Ad-MSCs-SF patches were transplanted and the efficacy of treatments was assessed by measuring the wound closure area, by histological examination and by gene expression profile. We further investigated the in vitro angiogenic properties of Ad-MSCs-SF and D-Ad-MSCs-SF patches by affecting migration of human umbilical vein endothelial cells (HUVECs), keratinocytes (KCs) and dermal fibroblasts (DFs), through the aortic ring assay and, finally, by evaluating the release of angiogenic factors. Results We found that Ad-MSCs adhere and grow on SF, maintaining their phenotypic mesenchymal profile and differentiation capacity. Conformational and structural analyses on SF and D-Ad-MSCs-SF samples, showed that sterilization, decellularization, freezing and storing did not affect the SF structure. When grafted in wounds of diabetic mice, both Ad-MSCs-SF and D-Ad-MSCs-SF significantly improved tissue regeneration, reducing the wound area respectively by 40% and 35%, within three days, completing the process in around 10 days compared to 15–17 days of controls. RT2 gene profile analysis of the wounds treated with Ad-MSCs-SF and D-Ad-MSCs-SF showed an increment of genes involved in angiogenesis and matrix remodeling. Finally, Ad-MSCs-SF and D-Ad-MSCs-SF co-cultured with HUVECs, DFs and KCs, preferentially enhanced the HUVECs’ migration and the release of angiogenic factors stimulating microvessel outgrowth in the aortic ring assay. Conclusions Our results highlight for the first time that D-Ad-MSCs-SF patches are almost as effective as Ad-MSCs-SF patches in the treatment of diabetic wounds, acting through a complex mechanism that involves stimulation of angiogenesis. Our data suggest a potential use of D-Ad-MSCs-SF patches in chronic diabetic ulcers in humans. PMID:24423450

  1. Antinociceptive effects of fisetin against diabetic neuropathic pain in mice: Engagement of antioxidant mechanisms and spinal GABAA receptors.

    PubMed

    Zhao, Xin; Li, Xin-Lin; Liu, Xin; Wang, Chuang; Zhou, Dong-Sheng; Ma, Qing; Zhou, Wen-Hua; Hu, Zhen-Yu

    2015-12-01

    Peripheral painful neuropathy is one of the most common complications in diabetes and necessitates improved treatment. Fisetin, a naturally occurring flavonoid, has been reported to exert antidepressant-like effect in previous studies. As antidepressant drugs are employed clinically to treat neuropathic pain, this work aimed to investigate whether fisetin posses beneficial effect on diabetic neuropathic pain and explore the mechanism(s). We subjected mice to diabetes by a single intraperitoneal (i.p.) injection of streptozotocin (200mg/kg), and von Frey test or Hargreaves test was used to assess mechanical allodynia or thermal hyperalgesia, respectively. Chronic treatment of diabetic mice with fisetin not only ameliorated the established symptoms of thermal hyperalgesia and mechanical allodynia, but also arrested the development of neuropathic pain when given at low doses. Although chronic fisetin administration did not impact on the symptom of hyperglycemia in diabetic mice, it reduced exacerbated oxidative stress in tissues of spinal cord, dorsal root ganglion (DRG) and sciatic verve. Furthermore, the analgesic actions of fisetin were abolished by repetitive co-treatment with the reactive oxygen species (ROS) donor tert-butyl hydroperoxide (t-BOOH), but potentiated by the ROS scavenger phenyl-N-tert-butylnitrone (PBN). Finally, acute blockade of spinal GABAA receptors by bicuculline totally counteracted such fisetin analgesia. These findings indicate that chronic fisetin treatment can delay or correct neuropathic hyperalgesia and allodynia in mice with type 1 diabetes. Mechanistically, the present fisetin analgesia may be associated with its antioxidant activity, and spinal GABAA receptors are likely rendered as downstream targets. PMID:26520392

  2. Defects in the Acquisition of Tumor-Killing Capability of CD8+ Cytotoxic T Cells in Streptozotocin-Induced Diabetic Mice

    PubMed Central

    Chen, Shu-Ching; Su, Yu-Chia; Lu, Ya-Ting; Ko, Patrick Chow-In; Chang, Pei-Yu; Lin, Hung-Ju; Ho, Hong-Nerng; Lai, Yo-Ping

    2014-01-01

    Emerging evidences have shown that diabetes mellitus not only raises risk but also heightens mortality rate of cancer. It is not clear, however, whether antitumor CD8+ cytotoxic T lymphocyte (CTL) response is down-modulated in diabetic hosts. We investigated the impact of hyperglycemia on CTLs' acquisition of tumor-killing capability by utilizing streptozotocin-induced diabetic (STZ-diabetic) mice. Murine diabetes was induced by intraperitoneal injection of STZ (200 mg/kg) in C57BL/6 mice, 2C-T cell receptor (TCR) transgenic and P14-TCR transgenic mice. The study found that, despite harboring intact proliferative capacity measured with CFSE labeling and MTT assay, STZ-diabetic CD8+ CTLs displayed impaired effector functions. After stimulation, STZ-diabetic CD8+ CTLs produced less perforin and TNF? assessed by intracellular staining, as well as expressed less CD103 protein. Furthermore, adoptive transfer of STZ-diabetic P14 CD8+ effector cells showed an insufficient recruitment to the B16.gp33 melanoma and inadequate production of perforin, granzyme B and TNF? determined by immunohistochemistry in the tumor milieu. As a result, STZ-diabetic CD8+ effector cells were neither able to eliminate tumor nor to improve survival of tumor-bearing mice. Taken together, our data suggest that CD8+ CTLs are crippled to infiltrate into tumors and thus fail to acquire tumor-killing capability in STZ-diabetic hosts. PMID:25390652

  3. Antioxidant and anti-diabetic potential of Passiflora alata Curtis aqueous leaves extract in type 1 diabetes mellitus (NOD-mice).

    PubMed

    Colomeu, T C; Figueiredo, D; Cazarin, C B B; Schumacher, N S G; Maróstica, M R; Meletti, L M M; Zollner, R L

    2014-01-01

    Leaves of Passiflora alata Curtis were characterized for their antioxidant capacity. Antioxidant analyses of DPPH, FRAP, ABTS, ORAC and phenolic compounds were made in three different extracts: aqueous, methanol/acetone and ethanol. Aqueous extract was found to be the best solvent for recovery of phenolic compounds and antioxidant activity, when compared with methanol/acetone and ethanol. To study the anti-inflammatory properties of this extract in experimental type 1 diabetes, NOD mice were divided into two groups: the P. alata group, treated with aqueous extract of P. alata Curtis, and a non-treated control group, followed by diabetes expression analysis. The consumption of aqueous extract and water ad libitum lasted 28 weeks. The treated-group presented a decrease in diabetes incidence, a low quantity of infiltrative cells in pancreatic islets and increased glutathione in the kidney and liver (p<0.05), when compared with the diabetic and non-diabetic control-groups. In conclusion, our results suggest that the consumption of aqueous extract of P. alata may be considered a good source of natural antioxidants and compounds found in its composition can act as anti-inflammatory agents, helping in the control of diabetes. PMID:24269180

  4. Transient cytokine treatment induces acinar cell reprogramming and regenerates functional beta cell mass in diabetic mice

    PubMed Central

    Baeyens, Luc; Lemper, Marie; Leuckx, Gunter; De Groef, Sofie; Bonfanti, Paola; Stangé, Geert; Shemer, Ruth; Nord, Christoffer; Scheel, David W.; Pan, Fong C.; Ahlgren, Ulf; Gu, Guoqiang; Stoffers, Doris A.; Dor, Yuval; Ferrer, Jorge; Gradwohl, Gerard; Wright, Christopher VE; Van de Casteele, Mark; German, Michael S.; Bouwens, Luc; Heimberg, Harry

    2014-01-01

    Reprogramming of pancreatic exocrine cells into cells resembling beta cells may provide a strategy for treating diabetes. Here we show that transient administration of epidermal growth factor and ciliary neurotrophic factor to adult mice with chronic hyperglycemia efficiently stimulates the conversion of terminally differentiated acinar cells to beta-like cells. Newly generated beta-like cells are epigenetically reprogrammed, functional and glucose-responsive, and reinstate normal glycemic control for up to 248 days. The regenerative process depends on Stat3 signaling and requires a threshold number of Neurogenin 3 (Ngn3) expressing acinar cells. In contrast to previous work demonstrating in vivo conversion of acinar cells to beta-like cells by viral delivery of exogenous transcription factors, our approach achieves acinar-to-beta cell reprogramming through transient cytokine exposure rather than genetic modification. PMID:24240391

  5. Mechanisms for antidiabetic effect of gingerol in cultured cells and obese diabetic model mice.

    PubMed

    Son, Myoung Jin; Miura, Yutaka; Yagasaki, Kazumi

    2015-08-01

    There have been studies on health beneficial effects of ginger and its components. However, there still remain certain aspects that are not well defined in their anti-hyperglycemic effects. Our aims were to find evidence of possible mechanisms for antidiabetic action of [6]-gingerol, a pungent component of ginger, employing a rat skeletal muscle-derived cell line, a rat-derived pancreatic ?-cell line, and type 2 diabetic model animals. The antidiabetic effect of [6]-gingerol was investigated through studies on glucose uptake in L6 myocytes and on pancreatic ?-cell protective ability from reactive oxygen species (ROS) in RIN-5F cells. Its in vivo effect was also examined using obese diabetic db/db mice. [6]-Gingerol increased glucose uptake under insulin absent condition and induced 5' adenosine monophosphate-activated protein kinase phosphorylation in L6 myotubes. Promotion by [6]-gingerol of glucose transporter 4 (GLUT4) translocation to plasma membrane was visually demonstrated by immunocytochemistry in L6 myoblasts transfected with glut4 cDNA-coding vector. [6]-Gingerol suppressed advanced glycation end product-induced rise of ROS levels in RIN-5F pancreatic ?-cells. [6]-Gingerol feeding suppressed the increases in fasting blood glucose levels and improved glucose intolerance in db/db mice. [6]-Gingerol regulated hepatic gene expression of enzymes related to glucose metabolism toward decreases in gluconeogenesis and glycogenolysis as well as an increase in glycogenesis, thereby contributing to reductions in hepatic glucose production and hence blood glucose concentrations. These in vitro and in vivo results strongly suggest that [6]-gingerol has antidiabetic potential through multiple mechanisms. PMID:24794903

  6. Antidiabetic Effect of Morinda citrifolia (Noni) Fermented by Cheonggukjang in KK-Ay Diabetic Mice

    PubMed Central

    Lee, So-Young; Park, So-Lim; Hwang, Jin-Taek; Yi, Sung-Hun; Nam, Young-Do; Lim, Seong-Il

    2012-01-01

    Antidiabetic effects of Morinda citrifolia (aka Noni) fermented by Cheonggukjang (fast-fermented soybean paste) were evaluated using a T2DM (type 2 diabetes mellitus) murine model. Six-week-old KK-Ay/TaJcl mice were randomly divided into four groups: (1) the diabetic control (DC) group, provided with a normal mouse diet; (2) the positive control (PC) group, provided with a functional health food diet; (3) the M. citrifolia (MC) group, provided with an MC-based diet; (4) the fermented M. citrifolia (FMC) group, provided with an FMC-based diet. Over a testing period of 90 days, food and water intake decreased significantly in the FMC and PC groups compared with the DC group. Blood glucose levels in the FMC group were 211.60–252.20?mg/dL after 90 days, while those in the control group were over 400?mg/dL after 20 days. In addition, FMC supplementation reduced glycosylated hemoglobin (HbA1c) levels, enhanced insulin sensitivity, and significantly decreased serum triglycerides and low-density lipoprotein (LDL) cholesterol. Furthermore, a fermented M. citrifolia 70% ethanolic extract (FMCE) activated peroxisome proliferator-activated receptor-(PPAR-) ? and stimulated glucose uptake via stimulation of AMP-activated protein kinase (AMPK) in cultured C2C12 cells. These results suggest that FMC can be employed as a functional health food for T2DM management. PMID:22969823

  7. Fucoxanthin regulates adipocytokine mRNA expression in white adipose tissue of diabetic/obese KK-Ay mice.

    PubMed

    Hosokawa, Masashi; Miyashita, Tatsuya; Nishikawa, Sho; Emi, Shingo; Tsukui, Takayuki; Beppu, Fumiaki; Okada, Tomoko; Miyashita, Kazuo

    2010-12-01

    Fucoxanthin, a marine carotenoid found in edible brown seaweeds, attenuates white adipose tissue (WAT) weight gain and hyperglycemia in diabetic/obese KK-A(y) mice, although it does not affect these parameters in lean C57BL/6J mice. In perigonadal and mesenteric WATs of KK-A(y) mice fed fucoxanthin, mRNA expression levels of monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-? (TNF-?), which are considered to induce insulin resistance, were markedly reduced compared to control mice. In contrast to KK-A(y) mice, fucoxanthin did not alter MCP-1 and TNF-? mRNA expression levels in the WAT of lean C57BL/6J mice. Interleukin-6 (IL-6) and plasminogen activator inhibitor-1 mRNA expression levels in WAT were also decreased by fucoxanthin in KK-A(y) mice. In differentiating 3T3-F442A adipocytes, fucoxanthinol, which is a fucoxanthin metabolite found in WAT, attenuated TNF-?-induced MCP-1 and IL-6 mRNA overexpression and protein secretion into the culture medium. In addition, fucoxanthinol decreased TNF-?, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) mRNA expression in RAW264.7 macrophage-like cells stimulated by palmitic acid. These findings indicate that fucoxanthin regulates mRNA expression of inflammatory adipocytokines involved in insulin resistance, iNOS, and COX-2 in WAT and has specific effects on diabetic/obese KK-A(y) mice, but not on lean C57BL/6J mice. PMID:20515643

  8. Influence of fluoride on streptozotocin induced diabetic nephrotoxicity in mice: Protective role of Asian ginseng (Panax ginseng) & banaba (Lagerstroemia speciosa) on mitochondrial oxidative stress

    PubMed Central

    Basha, Mahaboob P.; Saumya, S.M.

    2013-01-01

    Background & objectives: Chronic fluoride intoxication through drinking water is a serious health problem. Patients with diabetes are known to have impaired renal function and elimination of fluoride from the body is mainly done through kidney. Fluoride toxicity in diabetes patients may aggravate complications. In this study, the influence of fluoride was assessed on streptozotocin (STZ) induced diabetes in mice as also the efficacy/protective effective of oral supplementation of ginseng (GE) and banaba leaf extracts (BLE). Methods: The efficacy of plant extracts, GE and BLE at doses of 50, 150, 250 mg/kg b.w./day alone and in combination, was tested for a period of 15 days on fluoride treated STZ induced diabetic animals. Results: Fluoride exposure to mice with STZ-induced diabetes produced significant changes in OSI (organo-somatic index), fluoride content, blood glucose, urea, serum creatinine and oxidative stress indices in kidney tissues with evident histological alterations. Among the antioxidant treatments, combination therapy of GE and BLE at 150 mg/kg b.w. significantly normalized the impaired biochemical variables in kidney tissues of fluoride toxicated diabetic mice. Interpretations & conclusions: High fluoride uptake was found to be diabetogenic and further aggravated the renal oxidative damage and thereby the toxicity in mice with STZ induced diabetes mice. GE and BLE exposure individually or in combination at a dose of 150 mg/kg b.w./day for 15 days exhibited protective effects on fluoride toxicated STZ induced nephrotoxicity in mice. PMID:23563382

  9. Eleutheroside E, An Active Component of Eleutherococcus senticosus, Ameliorates Insulin Resistance in Type 2 Diabetic db/db Mice

    PubMed Central

    Ahn, Jiyun; Um, Min Young; Lee, Hyunjung; Jung, Chang Hwa; Heo, Seok Hyun; Ha, Tae Youl

    2013-01-01

    Eleutheroside E (EE), a principal component of Eleutherococcus senticosus (ES), has anti-inflammatory and protective effects in ischemia heart. However, it is unknown whether it ameliorates insulin resistance and reduces hyperglycemia in diabetes. This study investigated the effect of EE-containing ES extracts, as well as EE, on hyperglycemia and insulin resistance in db/db mice. EE increased the insulin-provoked glucose uptake in C2C12 myotubes. Moreover, EE improved TNF-?-induced suppression of glucose uptake in 3T3-L1 adipocytes. Five-week-old db/db mice were fed a diet consisting of ES extract or EE for 5 weeks. Both were effective in improving serum lipid profiles and significantly decreased blood glucose and serum insulin levels. ES and EE supplementation effectively attenuated HOMA-IR. Glucose tolerance and insulin tolerance tests showed that EE increased insulin sensitivity. Immunohistochemical staining indicated that ES and EE protected pancreatic alpha and beta cells from diabetic damage. In addition, ES and EE improved hepatic glucose metabolism by upregulating glycolysis and downregulating gluconeogenesis in obese type 2 diabetic mice. These data suggest that EE mediates the hyperglycemic effects of ES by regulating insulin signaling and glucose utilization. The beneficial effects of EE may provide an effective and powerful strategy to alleviate diabetes. PMID:23690865

  10. High Glucose Concentration Promotes Vancomycin-Enhanced Biofilm Formation of Vancomycin-Non-Susceptible Staphylococcus aureus in Diabetic Mice

    PubMed Central

    Lin, Mei-Hui; Chong, Kowit-Yu; Chen, Chien-Cheng; Wen, Shu-Min; Hsieh, Yi-Ting; Liao, Wan-Ting

    2015-01-01

    We previously demonstrated that vancomycin treatment increased acquisition of eDNA and enhanced biofilm formation of drug-resistant Staphylococcus aureus through a cidA-mediated autolysis mechanism. Recently we found that such enhancement became more significant under a higher glucose concentration in vitro. We propose that besides improper antibiotic treatment, increased glucose concentration environment in diabetic animals may further enhance biofilm formation of drug-resistant S. aureus. To address this question, the diabetic mouse model infected by vancomycin-resistant S. aureus (VRSA) was used under vancomycin treatment. The capacity to form biofilms was evaluated through a catheter-associated biofilm assay. A 10- and 1000-fold increase in biofilm-bound bacterial colony forming units was observed in samples from diabetic mice without and with vancomycin treatment, respectively, compared to healthy mice. By contrast, in the absence of glucose vancomycin reduced propensity to form biofilms in vitro through the increased production of proteases and DNases from VRSA. Our study highlights the potentially important role of increased glucose concentration in enhancing biofilm formation in vancomycin-treated diabetic mice infected by drug-resistant S. aureus. PMID:26244880

  11. The PHSRN sequence induces extracellular matrix invasion and accelerates wound healing in obese diabetic mice

    PubMed Central

    Livant, Donna L.; Brabec, R. Kaye; Kurachi, Kotoku; Allen, David L.; Wu, Yanling; Haaseth, Ronald; Andrews, Philip; Ethier, Stephen P.; Markwart, Sonja

    2000-01-01

    The PHSRN sequence of the plasma fibronectin (pFn) cell-binding domain induces human keratinocytes and fibroblasts to invade the naturally serum-free extracellular matricies of sea urchin embryos. The potency of acetylated, amidated PHSRN (Ac-PHSRN-NH2) is significantly increased, making it more active on a molar basis than the 120-kDa cell-binding domain of pFn. Arginine is important to this activity because PHSAN and PHSEN are inactive, as is a randomized sequence peptide, Ac-HSPNR-NH2. One treatment with Ac-PHSRN-NH2 stimulates reepithelialization and contraction of dermal wounds in healing-impaired, obese diabetic C57BL6/KsJ db/db mice. Wound closure is equally rapid in treated db/db and db/+ mice and may be more rapid than in untreated nondiabetic db/+ littermates. In contrast, treatment with either Ac-HSPNR-NH2 or normal saline (NS) has no effect. Analysis of sectioned db/db wounds shows that, in contrast to treatment with Ac-HSPNR-NH2 or NS, a single Ac-PHSRN-NH2 treatment stimulates keratinocyte and fibroblast migration into wounds, enhances fibroplasia and vascularization in the provisional matrix, and stimulates the formation of prominent fibers that may be associated with wound contraction. PMID:10841512

  12. Novel small-molecule AMPK activator orally exerts beneficial effects on diabetic db/db mice.

    PubMed

    Li, Yuan-Yuan; Yu, Li-Fang; Zhang, Li-Na; Qiu, Bei-Ying; Su, Ming-Bo; Wu, Fang; Chen, Da-Kai; Pang, Tao; Gu, Min; Zhang, Wei; Ma, Wei-Ping; Jiang, Hao-Wen; Li, Jing-Ya; Nan, Fa-Jun; Li, Jia

    2013-12-01

    AMP-activated protein kinase (AMPK), which is a pivotal guardian of whole-body energy metabolism, has become an attractive therapeutic target for metabolic syndrome. Previously, using a homogeneous scintillation proximity assay, we identified the small-molecule AMPK activator C24 from an optimization based on the original allosteric activator PT1. In this paper, the AMPK activation mechanism of C24 and its potential beneficial effects on glucose and lipid metabolism on db/db mice were investigated. C24 allosterically stimulated inactive AMPK ? subunit truncations and activated AMPK heterotrimers by antagonizing autoinhibition. In primary hepatocytes, C24 increased the phosphorylation of AMPK downstream target acetyl-CoA carboxylase dose-dependently without changing intracellular AMP/ATP ratio, indicating its allosteric activation in cells. Through activating AMPK, C24 decreased glucose output by down-regulating mRNA levels of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) in primary hepatocytes. C24 also decreased the triglyceride and cholesterol contents in HepG2 cells. Due to its improved bioavailability, chronic oral treatment with multiple doses of C24 significantly reduced blood glucose and lipid levels in plasma, and improved the glucose tolerance of diabetic db/db mice. The hepatic transcriptional levels of PEPCK and G6Pase were reduced. These results demonstrate that this orally effective activator of AMPK represents a novel approach to the treatment of metabolic syndrome. PMID:24055643

  13. Asiatic acid and maslinic acid protected heart via anti-glycative and anti-coagulatory activities in diabetic mice.

    PubMed

    Hung, Yi-chih; Yang, Hui-ting; Yin, Mei-chin

    2015-09-01

    The cardiac protective effects of asiatic acid (AA) and maslinic acid (MA) in diabetic mice were examined. These triterpenoids at 0.1 or 0.2% of the diet were supplied to diabetic mice for 12 weeks. The AA or MA treatments decreased plasma glucose and HbA1c levels, and creatine phosphokinase and lactate dehydrogenase activities in diabetic mice (p < 0.05). AA or MA intake increased the amount deposited in the heart which retained the cardiac glutathione content and reduced the production of reactive oxygen species, N(?)-(carboxymethyl)-lysine, pentosidine, methylglyoxal, interleukin-6, tumor necrosis factor-alpha and monocyte chemoattractant protein-1 in the hearts of diabetic mice (p < 0.05). AA or MA intake lowered plasma von Willebrand factor and fibrinogen levels, and factor VII activity (p < 0.05), also AA or MA intake maintained circulating antithrombin-III and protein C activities (p < 0.05). AA or MA treatments down-regulated cardiac expression of NADPH oxidase, aldose reductase, nuclear factor kappa B (NF-?B) p65 and p-p38; as well as reserving glyoxalase 1 expression (p < 0.05). These two compounds at only 0.2% lowered cardiac expression of NF-?B p50, p-ERK1/2 and the receptor of the advanced glycation endproduct (p < 0.05). These findings support the conclusion that the supplement of these triterpenoids could protect the heart under diabetic conditions via attenuating glycative injury and coagulatory disorders. PMID:26190771

  14. Preventative role of interleukin-17 producing regulatory T helper type 17 (Treg 17) cells in type 1 diabetes in non-obese diabetic mice.

    PubMed

    Bellemore, S M; Nikoopour, E; Schwartz, J A; Krougly, O; Lee-Chan, E; Singh, B

    2015-12-01

    T helper type 17 (Th17) cells have been shown to be pathogenic in autoimmune diseases; however, their role in type 1 diabetes (T1D) remains inconclusive. We have found that Th17 differentiation of CD4(+) T cells from BDC2·5 T cell receptor transgenic non-obese diabetic (NOD) mice can be driven by interleukin (IL)-23?+?IL-6 to produce large amounts of IL-22, and these cells induce T1D in young NOD mice upon adoptive transfer. Conversely, polarizing these cells with transforming growth factor (TGF)-??+?IL-6 led to non-diabetogenic regulatory Th17 (Treg 17) cells that express high levels of aryl hydrocarbon receptor (AhR) and IL-10 but produced much reduced levels of IL-22. The diabetogenic potential of these Th17 subsets was assessed by adoptive transfer studies in young NOD mice and not NOD.severe combined immunodeficient (SCID) mice to prevent possible transdifferentiation of these cells in vivo. Based upon our results, we suggest that both pathogenic Th17 cells and non-pathogenic regulatory Treg 17 cells can be generated from CD4(+) T cells under appropriate polarization conditions. This may explain the contradictory role of Th17 cells in T1D. The IL-17 producing Treg 17 cells offer a novel regulatory T cell population for the modulation of autoimmunity. PMID:26250153

  15. Diabetes

    MedlinePLUS

    ... 01, 2011 National Diabetes Education Program. Overview of Diabetes in Children and Adolescents. Accessed January 01, 2011 National Institutes of Health. Type 1 Diabetes Fact Sheet. Accessed January 01, 2011 Diagnosis and ...

  16. A potent and selective 11?-hydroxysteroid dehydrogenase type 1 inhibitor, SKI2852, ameliorates metabolic syndrome in diabetic mice models.

    PubMed

    Oh, Hyunhee; Jeong, Kyeong-Hoon; Han, Hye Young; Son, Hyun Joo; Kim, Su Sung; Lee, Hyun Jung; Kim, Shinae; Sa, Joon Ho; Jun, Hee-Sook; Ryu, Je Ho; Choi, Cheol Soo

    2015-12-01

    11?-Hydroxysteroid dehydrogenase type 1 (11?HSD1) has been targeted for new drugs to treat type 2 diabetes and metabolic syndrome. In this study, we determined whether the inhibition of 11?HSD1 with a new selective inhibitor, SKI2852, could improve lipid profiles, glucose levels, and insulin sensitivity in type 2 diabetic and obese conditions. SKI2852 showed a potent inhibition of cortisone to cortisol conversion for over 80% in both liver and adipose tissue ex vivo from orally administered C57BL/6 mice, and in vivo analysis results were consistent with this. Repeated oral administrations of SKI2852 in diet-induced obesity (DIO) and ob/ob mice revealed a partially beneficial effect of SKI2852 in improving levels of cholesterols, triglycerides, free fatty acids, postprandial glucose, and/or blood hemoglobinA1c. SKI2852 significantly reduced body weight increase in ob/ob mice, and efficiently suppressed hepatic mRNA levels of gluconeogenic enzymes in DIO mice. Moreover, SKI2852 enhanced hepatic and whole body insulin sensitivities in hyperinsulinemic-euglycemic clamp experiment in DIO mice. In conclusion, these results indicate that selective and potent inhibition of 11?HSD1 by SKI2852, thus blockade of active glucocorticoid conversion, may improve many aspects of metabolic parameters in type 2 diabetes and metabolic diseases, mainly by inhibitions of hepatic gluconeogenesis and partial improvements of lipid profiles. Our study strongly support that SKI2852 may have a great potential as a novel candidate drug for the treatment of diabetes and metabolic diseases. PMID:26519792

  17. VGF Peptide Profiles in Type 2 Diabetic Patients’ Plasma and in Obese Mice

    PubMed Central

    D’Amato, Filomena; Noli, Barbara; Angioni, Laura; Cossu, Efisio; Incani, Michela; Messana, Irene; Manconi, Barbara; Solinas, Paola; Isola, Raffaella; Mariotti, Stefano; Ferri, Gian-Luca; Cocco, Cristina

    2015-01-01

    To address the possible involvement of VGF peptides in obesity and diabetes, we studied type 2 diabetes (T2D) and obese patients, and high-fat diet induced obese mice. Two VGF peptides (NAPP-19 and QQET-30) were identified in human plasma by HPLC-ESI-MS. The VGF C-terminus, the above two cleaved peptides, and the TLQP-21 related peptide/s were studied using ELISA and immunohistochemistry. In euglycemic patients, plasma NAPPE and TLQP like peptides were significantly reduced with obesity (74±10 vs. 167±28, and 92±10 vs. 191±19 pmol/ml, mean+SEM, n = 10 and 6, obese vs. normal BMI, respectively, p<0.03). Upon a standard glucose load, a distinct response was shown for VGF C-terminus, TLQP and QQET-like (ERVW immunoreactive) peptides in euglycemic normal BMI patients, but was virtually abolished in euglycemic obese, and in T2D patients independently of BMI. High-fat diet induced obese mice showed reduced plasma VGF C-terminus, NAPPE and QQET-like (ERVW) peptide/s (3±0.2 vs. 4.6±0.3, 22±3.5 vs. 34±1.3, and 48±7 vs. 100±7 pmol/ml, mean+SEM, n = 8/group, obese vs. slim, respectively, p<0.03), with a loss of the response to glucose for all VGF peptides studied. In immunohistochemistry, TLQP and/or VGF C-terminus antibodies labelled VGF containing perikarya in mouse celiac ganglia, pancreatic islet cells and thin beaded nerve fibres in brown adipose tissues, with fewer in white adipose tissue. Upon the glucose load, tyrosine hydroxylase and VGF C-terminus immunoreactive axons became apparent in pancreatic islets of slim animals, but not in obese animals. Alltogether, a significant loss of VGF peptide immunoreactivity and/or their response to glucose was demonstrated in obese patients, with or without T2D, in parallel with a similar loss in high-fat diet induced obese mice. An involvement of VGF in metabolic regulations, including those of brown and/or white adipose tissues is underlined, and may point out specific VGF peptides as potential targets for diagnosis and/or treatment. PMID:26562304

  18. L-Arginine ameliorates cardiac left ventricular oxidative stress by upregulating eNOS and Nrf2 target genes in alloxan-induced hyperglycemic rats

    SciTech Connect

    Ramprasath, Tharmarajan; Hamenth Kumar, Palani; Syed Mohamed Puhari, Shanavas; Senthil Murugan, Ponniah; Vasudevan, Varadaraj; Selvam, Govindan Sadasivam

    2012-11-23

    Highlights: Black-Right-Pointing-Pointer L-Arginine treatment reduced the metabolic disturbances in diabetic animals. Black-Right-Pointing-Pointer Antioxidant marker proteins were found high in myocardium by L-arginine treatment. Black-Right-Pointing-Pointer Elevated antioxidant status, mediates the reduced TBA-reactivity in left ventricle. Black-Right-Pointing-Pointer L-Arginine treatment enhanced the Nrf2 and eNOS signaling in left ventricle. Black-Right-Pointing-Pointer Improved cell survival signaling by arginine, offers a novel tactic for targeting. -- Abstract: Hyperglycemia is independently related with excessive morbidity and mortality in cardiovascular disorders. L-Arginine-nitric oxide (NO) pathway and the involvement of NO in modulating nuclear factor-E2-related factor-2 (Nrf2) signaling were well established. In the present study we investigated, whether L-arginine supplementation would improve the myocardial antioxidant defense under hyperglycemia through activation of Nrf2 signaling. Diabetes was induced by alloxan monohydrate (90 mg kg{sup -1} body weight) in rats. Both non-diabetic and diabetic group of rats were divided into three subgroups and they were administered either with L-arginine (2.25%) or L-NAME (0.01%) in drinking water for 12 days. Results showed that L-arginine treatment reduced the metabolic disturbances in diabetic rats. Antioxidant enzymes and glutathione levels were found to be increased in heart left ventricles, thereby reduction of lipid peroxidation by L-arginine treatment. Heart histopathological analysis further validates the reversal of typical diabetic characteristics consisting of alterations in myofibers and myofibrillary degeneration. qRT-PCR studies revealed that L-arginine treatment upregulated the transcription of Akt and downregulated NF-{kappa}B. Notably, transcription of eNOS and Nrf2 target genes was also upregulated, which were accompanied by enhanced expression of Nrf2 in left ventricular tissue from diabetic and control rats. Under these findings, we suggest that targeting of eNOS and Nrf2 signaling by L-arginine supplementation could be used as a potential treatment method to alleviate the late diabetic complications.

  19. Effects of brown alga, Ecklonia cava on glucose and lipid metabolism in C57BL/KsJ-db/db mice, a model of type 2 diabetes mellitus.

    PubMed

    Lee, Seung-Hong; Min, Kwan-Hee; Han, Ji-Sook; Lee, Dae-Ho; Park, Deok-Bae; Jung, Won-Kyo; Park, Pyo-Jam; Jeon, Byong-Tae; Kim, Se-Kwon; Jeon, You-Jin

    2012-03-01

    Recently, there has been a growing interest in alternative therapies of marine algae for diabetes. Therefore, the anti-diabetic effects of brown alga, Ecklonia cava was investigated in type 2 diabetic animal. Male C57BL/KsJ-db/db (db/db) mice were divided into control, dieckol rich extract of E. cava (AG-dieckol), or rosiglitazone (RG) groups. The blood glucose, blood glycosylated hemoglobin levels, and plasma insulin levels were significantly lower in the AG-dieckol and RG groups than in the control db/db mice group, while glucose tolerance was significantly improved in the AG-dieckol group. AG-dieckol markedly lowered plasma and hepatic lipids concentration compared to the control db/db mice group. The antioxidant enzyme activities were significantly higher in the AG-dieckol group than in the control db/db mice group, yet its TBARS level was markedly lower compared to the RG group. With regard to hepatic glucose regulating enzyme activities, glucokinase activity was enhanced in the AG-dieckol group mice, while glucose-6-phosphatase and phosphoenolpyruvate carboxykinase activities in the AG-dieckol group mice were significantly lowered than those in the control db/db mice group. These results suggest that AG-dieckol exert an anti-diabetic effect in type 2 diabetic mice by improving the glucose and lipid metabolism and antioxidant enzymes. PMID:22227338

  20. In vivo imaging of oxidative stress in the kidney of diabetic mice and its normalization by angiotensin II type 1 receptor blocker

    SciTech Connect

    Sonta, Toshiyo; Inoguchi, Toyoshi . E-mail: toyoshi@intmed3.med.kyushu-u.ac.jp; Matsumoto, Shingo; Yasukawa, Keiji; Inuo, Mieko; Tsubouchi, Hirotaka; Sonoda, Noriyuki; Kobayashi, Kunihisa; Utsumi, Hideo; Nawata, Hajime

    2005-05-06

    This study was undertaken to evaluate oxidative stress in the kidney of diabetic mice by electron spin resonance (ESR) imaging technique. Oxidative stress in the kidney was evaluated as organ-specific reducing activity with the signal decay rates of carbamoyl-PROXYL probe using ESR imaging. The signal decay rates were significantly faster in corresponding image pixels of the kidneys of streptozotocin-induced diabetic mice than in those of controls. This technique further demonstrated that administration of angiotensin II type 1 receptor blocker (ARB), olmesartan (5 mg/kg), completely restored the signal decay rates in the diabetic kidneys to control values. In conclusion, this study provided for the first time the in vivo evidence for increased oxidative stress in the kidneys of diabetic mice and its normalization by ARB as evaluated by ESR imaging. This technique would be useful as a means of further elucidating the role of oxidative stress in diabetic nephropathy.

  1. In vitro vitamin K2 and 1?,25-dihydroxyvitamin D3 combination enhances osteoblasts anabolism of diabetic mice.

    PubMed

    Poon, Christina C W; Li, Rachel W S; Seto, Sai Wang; Kong, Siu Kai; Ho, Ho Pui; Hoi, Maggie P M; Lee, Simon M Y; Ngai, Sai Ming; Chan, Shun Wan; Leung, George P H; Kwan, Yiu Wa

    2015-11-15

    In this study, we evaluated the anabolic effect and the underlying cellular mechanisms involved of vitamin K2 (10nM) and 1?,25-dihydroxyvitamin D3 (1,25(OH)2D3) (10nM), alone and in combination, on primary osteoblasts harvested from the iliac crests of C57BL/KsJ lean (+/+) and obese/diabetic (db/db) mice. A lower alkaline phosphatase (ALP) activity plus a reduced expression of bone anabolic markers and bone formation transcription factors (osteocalcin, Runx2, Dlx5, ATF4 and OSX) were consistently detected in osteoblasts of db/db mice compared to lean mice. A significantly higher calcium deposits formation in osteoblasts was observed in lean mice when compared to db/db mice. Co-administration of vitamin K2 (10nM) and 1,25(OH)2D3 (10nM) caused an enhancement of calcium deposits in osteoblasts in both strains of mice. Vitamins K2 and 1,25(OH)2D3 co-administration time-dependently (7, 14 and 21 days) increased the levels of bone anabolic markers and bone formation transcription factors, with a greater magnitude of increase observed in osteoblasts of db/db mice. Combined vitamins K2 plus 1,25(OH)2D3 treatment significantly enhanced migration and the re-appearance of surface microvilli and ruffles of osteoblasts of db/db mice. Thus, our results illustrate that vitamins K2 plus D3 combination could be a novel therapeutic strategy in treating diabetes-associated osteoporosis. PMID:26452518

  2. Skeletal muscle mitochondrial uncoupling prevents diabetes but not obesity in NZO mice, a model for polygenic diabesity.

    PubMed

    Voigt, Anja; Katterle, Yvonne; Kahle, Melanie; Kluge, Reinhart; Schürmann, Annette; Joost, Hans-Georg; Klaus, Susanne

    2015-11-01

    Induction of skeletal muscle (SM) mitochondrial stress by expression of uncoupling protein 1 (UCP1) in mice results in a healthy metabolic phenotype associated with increased secretion of FGF21 from SM. Here, we investigated whether SM mitochondrial uncoupling can compensate obesity and insulin resistance in the NZO mouse, a polygenic diabesity model. Male NZO mice were crossed with heterozygous UCP1 transgenic (tg) mice (mixed C57BL/6/CBA background) and further backcrossed to obtain F1 and N2 offspring with 50 and 75 % NZO background, respectively. Male F1 and N2 progeny were fed a high-fat diet ad libitum for 20 weeks from weaning. Blood glucose was reduced, and diabetes (severe hyperglycemia >300 mg/dl) was fully prevented in both F1- and N2-tg progeny compared to a diabetes prevalence of 15 % in F1 and 42 % in N2 wild type. In contrast, relative body fat content and plasma insulin were decreased, and glucose tolerance was improved, in F1-tg only. Both F1 and N2-tg showed decreased lean body mass. Accordingly, induction of SM stress response including FGF21 expression and secretion was similar in both F1 and N2-tg mice. In white adipose tissue, expression of FGF21 target genes was enhanced in F1 and N2-tg mice, whereas lipid metabolism genes were induced in F1-tg only. There was no evidence for induction of browning in either UCP1 backcross. We conclude that SM mitochondrial uncoupling induces FGF21 expression and prevents diabetes in mice with a 50-75 % NZO background independent of its effects on adipose tissue. PMID:26584809

  3. Ondansetron, a 5HT3 receptor antagonist reverses depression and anxiety-like behavior in streptozotocin-induced diabetic mice: possible implication of serotonergic system.

    PubMed

    Gupta, Deepali; Radhakrishnan, Mahesh; Kurhe, Yeshwant

    2014-12-01

    Increased prevalence and high comorbidity of depression-like mood disorders and diabetes have prompted investigation of new targets and potential contributing agents. There is considerable evidence supporting the inconsistent clinical efficacy and persistent undesirable effects of existing antidepressant therapy for depression associated with diabetes. Therefore, the present study was aimed at investigating the effect of ondansetron, a selective 5HT3 receptor antagonist in attenuating depression and anxiety-like behavior comorbid with diabetes. Experimentally, Swiss albino mice were rendered diabetic by a single intraperitoneal (i.p.) injection of streptozotocin (STZ, 200 mg/kg). After 8 weeks, diabetic mice received a single dose of vehicle/ondansetron (0.5 and 1 mg/kg, p.o.)/fluoxetine (the positive control, 10 mg/kg p.o.) for 28 days. Thereafter, behavioral studies were conducted to test depression-like behavior using forced swim test (FST) and anxiety-like deficits using hole-board and light-dark tests, followed by biochemical estimation of serotonin content in discrete brain regions. The results demonstrated that, STZ-induced diabetic mice exhibited increased duration of immobility and decreased swimming behavior in FST, reduced exploratory behavior during hole-board test and increased aversion to brightly illuminated light area in light-dark test as compared to non-diabetic mice, while ondansetron (similar to fluoxetine) treatment significantly reversed the same. Biochemical assay revealed that ondansetron administration attenuated diabetes-induced neurochemical impairment of serotonin function, indicated by elevated serotonin levels in discrete brain regions of diabetic mice. Collectively, the data indicate that ondansetron may reverse depression and anxiety-like behavioral deficits associated with diabetes in mice and modulation of serotonergic activity may be a key mechanism of the compound. PMID:25284215

  4. Vascular injury in diabetic db/db mice is ameliorated by atorvastatin: role of Rac1/2-sensitive Nox-dependent pathways.

    PubMed

    Bruder-Nascimento, Thiago; Callera, Glaucia E; Montezano, Augusto C; He, Ying; Antunes, Tayze T; Cat, Aurelie Nguyen Dinh; Tostes, Rita C; Touyz, Rhian M

    2015-04-01

    Oxidative stress [increased bioavailability of reactive oxygen species (ROS)] plays a role in the endothelial dysfunction and vascular inflammation, which underlie vascular damage in diabetes. Statins are cholesterol-lowering drugs that are vasoprotective in diabetes through unknown mechanisms. We tested the hypothesis that atorvastatin decreases NADPH oxidase (Nox)-derived ROS generation and associated vascular injury in diabetes. Lepr(db)/Lepr(db) (db/db) mice, a model of Type 2 diabetes and control Lepr(db)/Lepr(+) (db/+) mice were administered atorvastatin (10 mg/kg per day, 2 weeks). Atorvastatin improved glucose tolerance in db/db mice. Systemic and vascular oxidative stress in db/db mice, characterized by increased plasma TBARS (thiobarbituric acid-reactive substances) levels and exaggerated vascular Nox-derived ROS generation respectively, were inhibited by atorvastatin. Cytosol-to-membrane translocation of the Nox regulatory subunit p47(phox) and the small GTPase Rac1/2 was increased in vessels from db/db mice compared with db/+ mice, an effect blunted by atorvastatin. The increase in vascular Nox1/2/4 expression and increased phosphorylation of redox-sensitive mitogen-activated protein kinases (MAPKs) was abrogated by atorvastatin in db/db mice. Pro-inflammatory signalling (decreased I?B-? and increased NF-?B p50 expression, increased NF-?B p65 phosphorylation) and associated vascular inflammation [vascular cell adhesion molecule-1 (VCAM-1) expression and vascular monocyte adhesion], which were increased in aortas of db/db mice, were blunted by atorvastatin. Impaired acetylcholine (Ach)- and insulin (INS)-induced vasorelaxation in db/db mice was normalized by atorvastatin. Our results demonstrate that, in diabetic mice, atorvastatin decreases vascular oxidative stress and inflammation and ameliorates vascular injury through processes involving decreased activation of Rac1/2 and Nox. These findings elucidate redox-sensitive and Rac1/2-dependent mechanisms whereby statins protect against vascular injury in diabetes. PMID:25358739

  5. Linkage on chromosome 3 of autoimmune diabetes and defective Fc receptor for lgG in NOD mice

    SciTech Connect

    Prins, J.B.; Todd, J.A.; Rodrigues, N.R.; Ghosh, S. ); Hogarth, P.M. ); Wicker, L.S.; Podolin, P.L.; Gaffney, E.; Peterson, L.B.; Fischer, P.A.; Sirotina, A. )

    1993-04-30

    A congenic, non-obese diabetic (NOD) mouse strain that contains a segment of chromosome 3 from the diabetes-resistant mouse strain B6.PL-Thy-1[sup a] was less susceptible to diabetes than NOD mice. A fully penetrant immunological defect also mapped to this segment, which encodes the high-affinity Fc receptor for immunoglobulin G (lgG), Fc[gamma]Rl. The NOD Fcgr1 allele, which results in a deletion of the cytoplasmic tail, caused a 73 percent reduction in the turnover of cell surface receptor-antibody complexes. The development of congenic strains and the characterization of Mendelian traits that are specific to the disease phenotype demonstrate the feasibility of dissecting the pathophysiology of complex, non-Mendelian diseases.

  6. DIETS RICH IN POLYPHENOLS AND VITAMIN A INHIBIT THE DEVELOPMENT OF TYPE I AUTOIMMUNE DIABETES IN NONOBESE DIABETIC MICE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Type I juvenile diabetes mellitus is characterized by the infiltration of activated T lymphoctes and monocytes into the islets of Langerhans of the pancreas, resulting in inflammation and progressive destruction of the insulin-producing beta cells. We hypothesized that feeding nonobese diabetic (NO...

  7. Hypoglycemic Effect of Ethanol and Ethyl Acetate Extract of Phellinus baumii Fruiting Body in Streptozotocin-Induced Diabetic Mice

    PubMed Central

    Wang, Wen-Han; Wu, Fei-Hua; Yang, Yan; Wu, Na; Zhang, Jing-Song; Feng, Na; Tang, Chuan-Hong

    2015-01-01

    We investigated hypoglycemic effect of ethanol (EtOH) and ethyl acetate extract acetate (AcOEt) extracts in streptozotocin- (STZ-) induced diabetic mice. Our data showed the maximum inhibitory effect on the fasting plasma glucose (FPG) level was detected in STZ-induced diabetic mice administered with 400?mg/kg AcOEt extract of P. baumii. A lower glycated albumin (GA) level and a higher insulin level were observed in 400?mg/kg AcOEt and EtOH extract groups. Moreover, 400?mg/kg AcOEt and EtOH extract exhibited a stronger effect on increasing size and cell number of islets. The insulin expression level of ?-cells and integrated optical density (IOD) value were significantly increased by the administration of 400?mg/kg AcOEt and EtOH extracts. Taken together, AcOEt and EtOH extracts of P. baumii fruiting body exhibited considerable hypoglycemic effect on STZ-induced diabetic mice. PMID:26221177

  8. Mechanisms of defective glucose-induced insulin release in human pancreatic islets transplanted to diabetic nude mice.

    PubMed

    Eizirik, D L; Jansson, L; Flodström, M; Hellerström, C; Andersson, A

    1997-08-01

    We have previously observed that human islets, transplanted under the kidney capsule of hyperglycemic nude mice, show a longlasting impairment in glucose-induced insulin release. To investigate the cause(s) of this phenomenon, we transplanted human islets into normoglycemic or alloxan-diabetic nude mice for a 4- to 6-week period. In a third experimental group, aimed at evaluating reversibility of hyperglycemia effects, diabetic nude mice bearing a human islet graft were cured by a second intrasplenic transplant of mouse islets, and the human islets were exposed to a further 2 weeks of normoglycemia. Four to 6 weeks of hyperglycemia induced a severe impairment of glucose- and arginine-induced insulin release, as demonstrated by perfusion of the graft-bearing kidney. This defective release was not restored by a subsequent 2-week period of normoglycemia, and it was accompanied by normal (pro)insulin biosynthesis, glucose oxidation, and expression of insulin messenger RNA. Taken together with our previous study, these observations indicate that impaired glucose metabolism, depletion of insulin messenger RNA, decreased (pro)insulin biosynthesis, increased glycogen accumulation, and depletion of insulin reserves cannot explain the deleterious effects of the diabetic state on human islet insulin release. This, and the similar inhibition of glucose- and arginine-induced insulin release, suggest that prolonged hyperglycemia may exert its deleterious effect on insulin release at a step distal to closure of ATP-sensitive K-channels. PMID:9253350

  9. Label-free nonenzymatic glycation monitoring of collagen scaffolds in type 2 diabetic mice by confocal Raman microspectroscopy

    NASA Astrophysics Data System (ADS)

    Shi, Panpan; Liu, Hanping; Deng, Xiaoyuan; Jin, Ying; Wang, Qiannan; Liu, Hao; Chen, Maosheng; Han, Xue

    2015-02-01

    Collagen is the key target of nonenzymatic glycation during physiopathological processes such as diabetes. The induced changes in the biochemical property of collagen by nonenzymatic glycation remain a major challenge to probe. This study investigated the use of confocal Raman microspectroscopy to label-free monitor the nonenzymatic glycation of collagen scaffolds from type 2 diabetic (T2D) mice at different timepoints (0, 4, 8, and 12 weeks). The glycated collagen scaffolds were obtained through the decellularized dermal matrix method to remove the epidermis layer, subcutaneous tissue, and cells in the dermis and to retain the collagen fibrils. Raman spectra showed no changes in Raman peak positions, which indicated that nonenzymatic glycation could produce no significant changes in the triple-helix structure of collagen in T2D mice. However, the relative intensity of the Raman bands at 921, 1033, 1244, 1274, 1346, 1635, and 1672 cm-1 increased as diabetic time progressed. Correlation analysis suggested that the spectra of these bands had a high positive correlation with the expression of anti-advanced glycation end products obtained by immunofluorescence imaging of the same collagen scaffolds. Confocal Raman microspectroscopy proves a potential tool to label-free monitor the collagen changes caused by nonenzymatic glycation in T2D mice.

  10. Small Molecule Kaempferol Promotes Insulin Sensitivity and Preserved Pancreatic ?-Cell Mass in Middle-Aged Obese Diabetic Mice

    PubMed Central

    Alkhalidy, Hana; Moore, William; Zhang, Yanling; Wang, Aihua; Ali, Mostafa; Suh, Kyung-Shin; Zhen, Wei; Cheng, Zhiyong; Jia, Zhenquan; Hulver, Matthew

    2015-01-01

    Insulin resistance and a progressive decline in functional ?-cell mass are hallmarks of developing type 2 diabetes (T2D). Thus, searching for natural, low-cost compounds to target these two defects could be a promising strategy to prevent the pathogenesis of T2D. Here, we show that dietary intake of flavonol kaempferol (0.05% in the diet) significantly ameliorated hyperglycemia, hyperinsulinemia, and circulating lipid profile, which were associated with the improved peripheral insulin sensitivity in middle-aged obese mice fed a high-fat (HF) diet. Kaempferol treatment reversed HF diet impaired glucose transport-4 (Glut4) and AMP-dependent protein kinase (AMPK) expression in both muscle and adipose tissues from obese mice. In vitro, kaempferol increased lipolysis and prevented high fatty acid-impaired glucose uptake, glycogen synthesis, AMPK activity, and Glut4 expression in skeletal muscle cells. Using another mouse model of T2D generated by HF diet feeding and low doses of streptozotocin injection, we found that kaempferol treatment significantly improved hyperglycemia, glucose tolerance, and blood insulin levels in obese diabetic mice, which are associated with the improved islet ?-cell mass. These results demonstrate that kaempferol may be a naturally occurring anti-diabetic agent by improving peripheral insulin sensitivity and protecting against pancreatic ?-cell dysfunction. PMID:26064984

  11. Cytoprotective and anti-diabetic effects of Derris reticulata aqueous extract.

    PubMed

    Kumkrai, Pakarang; Kamonwannasit, Sirilak; Chudapongse, Nuannoi

    2014-09-01

    The current study was aimed to investigate pancreatic protective and anti-diabetic activities of the aqueous extract of Derris reticulata stem. First, we evaluated a cytoprotective potential of D. reticulata extract on alloxan-induced damage in vitro. Treatment with D. reticulata extract at the doses of 250 and 500 ?g/ml significantly increased cell viability of the pancreatic ?-cell line RINm5F after exposure of alloxan. The anti-hyperglycemic activity of D. reticulata extract was further studied in alloxan-induced diabetic rats. A significant reduction in blood glucose level along with an increase in body weight was observed in diabetic rats treated with D. reticulata extract at 250 mg/kg body weight for 15 days. Serum aspartate transaminase and alanine transaminase levels were also significantly decreased compared to diabetic control rats. In accordance with in vitro cytoprotective effect, histopathological examination revealed that pancreatic islet cells of the extract-treated diabetic rat were less damage than those of the untreated diabetic group. In order to find another possible mechanism of action underling hypoglycemic activity, the effect on glucose absorption was examined using everted sac jejunum. The results showed that D. reticulata extract suppressed glucose absorption from small intestine. To corroborate safety use of D. reticulata extract, acute oral toxicity was also conducted in rats. Our results showed that none of the tested doses (250, 500, 1,000, and 2,000 mg/kg) induced signs of toxicity or mortality after administration of the extract. The results suggested that D. reticulata extract possess anti-diabetic activity, which resulting from its pancreatic cytoprotective effect and inhibition of intestinal glucose absorption. PMID:24849669

  12. Ameliorative effect of riboflavin on hyperglycemia, oxidative stress and DNA damage in type-2 diabetic mice: Mechanistic and therapeutic strategies.

    PubMed

    Alam, Md Maroof; Iqbal, Sarah; Naseem, Imrana

    2015-10-15

    Increasing evidence in both experimental and clinical studies suggests that oxidative stress play a major role in the pathogenesis of type-2 diabetes mellitus (T2DM). Abnormally high levels of free radicals and the simultaneous decline of antioxidant defence mechanisms can lead to damage of cellular organelles and enzymes. Riboflavin constitutes an essential nutrient for humans and is also an important food additive for animals. It is a precursor of flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) which serves as a coenzyme for several enzymes. The aim of this study was to observe the effects of illuminated and non-illuminated riboflavin in a diabetic mice model. The protocol included treatment of diabetic mice with illuminated RF and a control set without light. To our surprise, group receiving RF without light gave better results in a dose dependent manner. Significant amelioration of oxidative stress was observed with an increased glucose uptake in skeletal muscles and white adipose tissue. Histological studies showed recovery in the liver and kidney tissue injury. Cellular DNA damage was also recovered. Therefore, it is suggested that supplementation with dietary riboflavin might help in the reduction of diabetic complications. A possible mechanism of action is also proposed. PMID:26319175

  13. Metformin Suppresses Diethylnitrosamine-Induced Liver Tumorigenesis in Obese and Diabetic C57BL/KsJ-+Leprdb/+Leprdb Mice

    PubMed Central

    Shirakami, Yohei; Baba, Atsushi; Kochi, Takahiro; Kubota, Masaya; Tsurumi, Hisashi; Tanaka, Takuji; Moriwaki, Hisataka

    2015-01-01

    Obesity and related metabolic disorders, such as diabetes mellitus, raise the risk of liver carcinogenesis. Metformin, which is widely used in the treatment of diabetes, ameliorates insulin sensitivity. Metformin is also thought to have antineoplastic activities and to reduce cancer risk. The present study examined the preventive effect of metformin on the development of diethylnitrosamine (DEN)-induced liver tumorigenesis in C57BL/KsJ-+Leprdb/+Leprdb (db/db) obese and diabetic mice. The mice were given a single injection of DEN at 2 weeks of age and subsequently received drinking water containing metformin for 20 weeks. Metformin administration significantly reduced the multiplicity of hepatic premalignant lesions and inhibited liver cell neoplasms. Metformin also markedly decreased serum levels of insulin and reduced insulin resistance, and inhibited phosphorylation of Akt, mammalian target of rapamycin (mTOR), and p70S6 in the liver. Furthermore, serum levels of leptin were decreased, while those of adiponectin were increased by metformin. These findings suggest that metformin prevents liver tumorigenesis by ameliorating insulin sensitivity, inhibiting the activation of Akt/mTOR/p70S6 signaling, and improving adipokine imbalance. Therefore, metformin may be a potent candidate for chemoprevention of liver tumorigenesis in patients with obesity or diabetes. PMID:25879666

  14. Combined vascular endothelial growth factor-A and fibroblast growth factor 4 gene transfer improves wound healing in diabetic mice

    PubMed Central

    2010-01-01

    Background Impaired wound healing in diabetes is related to decreased production of growth factors. Hence, gene therapy is considered as promising treatment modality. So far, efforts concentrated on single gene therapy with particular emphasis on vascular endothelial growth factor-A (VEGF-A). However, as multiple proteins are involved in this process it is rational to test new approaches. Therefore, the aim of this study was to investigate whether single AAV vector-mediated simultaneous transfer of VEGF-A and fibroblast growth factor 4 (FGF4) coding sequences will improve the wound healing over the effect of VEGF-A in diabetic (db/db) mice. Methods Leptin receptor-deficient db/db mice were randomized to receive intradermal injections of PBS or AAVs carrying ?-galactosidase gene (AAV-LacZ), VEGF-A (AAV-VEGF-A), FGF-4 (AAV-FGF4-IRES-GFP) or both therapeutic genes (AAV-FGF4-IRES-VEGF-A). Wound healing kinetics was analyzed until day 21 when all animals were sacrificed for biochemical and histological examination. Results Complete wound closure in animals treated with AAV-VEGF-A was achieved earlier (day 19) than in control mice or animals injected with AAV harboring FGF4 (both on day 21). However, the fastest healing was observed in mice injected with bicistronic AAV-FGF4-IRES-VEGF-A vector (day 17). This was paralleled by significantly increased granulation tissue formation, vascularity and dermal matrix deposition. Mechanistically, as shown in vitro, FGF4 stimulated matrix metalloproteinase-9 (MMP-9) and VEGF receptor-1 expression in mouse dermal fibroblasts and when delivered in combination with VEGF-A, enhanced their migration. Conclusion Combined gene transfer of VEGF-A and FGF4 can improve reparative processes in the wounded skin of diabetic mice better than single agent treatment. PMID:20804557

  15. Antibodies against insulin measured by electrochemiluminescence predicts insulitis severity and disease onset in non-obese diabetic mice and can distinguish human type 1 diabetes status

    PubMed Central

    2011-01-01

    Background The detection of insulin autoantibodies (IAA) aids in the prediction of autoimmune diabetes development. However, the long-standing, gold standard 125I-insulin radiobinding assay (RBA) has low reproducibility between laboratories, long sample processing times and requires the use of newly synthesized radiolabeled insulin for each set of assays. Therefore, a rapid, non-radioactive, and reproducible assay is highly desirable. Methods We have developed electrochemiluminescence (ECL)-based assays that fulfill these criteria in the measurement of IAA and anti-insulin antibodies (IA) in non-obese diabetic (NOD) mice and in type 1 diabetic individuals, respectively. Using the murine IAA ECL assay, we examined the correlation between IAA, histopathological insulitis, and blood glucose in a cohort of female NOD mice from 4 up to 36 weeks of age. We developed a human IA ECL assay that we compared to conventional RBA and validated using samples from 34 diabetic and 59 non-diabetic individuals in three independent laboratories. Results Our ECL assays were rapid and sensitive with a broad dynamic range and low background. In the NOD mouse model, IAA levels measured by ECL were positively correlated with insulitis severity, and the values measured at 8-10 weeks of age were predictive of diabetes onset. Using human serum and plasma samples, our IA ECL assay yielded reproducible and accurate results with an average sensitivity of 84% at 95% specificity with no statistically significant difference between laboratories. Conclusions These novel, non-radioactive ECL-based assays should facilitate reliable and fast detection of antibodies to insulin and its precursors sera and plasma in a standardized manner between laboratories in both research and clinical settings. Our next step is to evaluate the human IA assay in the detection of IAA in prediabetic subjects or those at risk of type 1 diabetes and to develop similar assays for other autoantibodies that together are predictive for the diagnosis of this common disorder, in order to improve prediction and facilitate future therapeutic trials. PMID:22123298

  16. Generation of N-Ethyl-N-nitrosourea (ENU) Diabetes Models in Mice Demonstrates Genotype-specific Action of Glucokinase Activators*

    PubMed Central

    Fenner, Deborah; Odili, Stella; Hong, Hee-Kyung; Kobayashi, Yumiko; Kohsaka, Akira; Siepka, Sandra M.; Vitaterna, Martha H.; Chen, Pan; Zelent, Bogumil; Grimsby, Joseph; Takahashi, Joseph S.; Matschinsky, Franz M.; Bass, Joseph

    2011-01-01

    We performed genome-wide mutagenesis in C57BL/6J mice using N-ethyl-N-nitrosourea to identify mutations causing high blood glucose early in life and to produce new animal models of diabetes. Of a total of 13 new lines confirmed by heritability testing, we identified two semi-dominant pedigrees with novel missense mutations (GckK140E and GckP417R) in the gene encoding glucokinase (Gck), the mammalian glucose sensor that is mutated in human maturity onset diabetes of the young type 2 and the target of emerging anti-hyperglycemic agents that function as glucokinase activators (GKAs). Diabetes phenotype corresponded with genotype (mild-to-severe: Gck+/+ < GckP417R/+, GckK140E/+ < GckP417R/P417R, GckP417R/K140E, and GckK140E/K140E) and with the level of expression of GCK in liver. Each mutant was produced as the recombinant enzyme in Escherichia coli, and analysis of kcat and tryptophan fluorescence (I320/360) during thermal shift unfolding revealed a correlation between thermostability and the severity of hyperglycemia in the whole animal. Disruption of the glucokinase regulatory protein-binding site (GCKK140E), but not the ATP binding cassette (GCKP417R), prevented inhibition of enzyme activity by glucokinase regulatory protein and corresponded with reduced responsiveness to the GKA drug. Surprisingly, extracts from liver of diabetic GCK mutants inhibited activity of the recombinant enzyme, a property that was also observed in liver extracts from mice with streptozotocin-induced diabetes. These results indicate a relationship between genotype, phenotype, and GKA efficacy. The integration of forward genetic screening and biochemical profiling opens a pathway for preclinical development of mechanism-based diabetes therapies. PMID:21921030

  17. Loss of Bradykinin Signaling Does Not Accelerate the Development of Cardiac Dysfunction in Type 1 Diabetic Akita Mice

    PubMed Central

    Wende, Adam R.; Soto, Jamie; Olsen, Curtis D.; Pires, Karla M. P.; Schell, John C.; Larrieu-Lahargue, Frederic; Litwin, Sheldon E.; Kakoki, Masao; Takahashi, Nobuyuki; Smithies, Oliver; Abel, E. Dale

    2010-01-01

    Bradykinin signaling has been proposed to play either protective or deleterious roles in the development of cardiac dysfunction in response to various pathological stimuli. To further define the role of bradykinin signaling in the diabetic heart, we examined cardiac function in mice with genetic ablation of both bradykinin B1 and B2 receptors (B1RB2R?/?) in the context of the Akita model of insulin-deficient type 1 diabetes (Ins2Akita/+). In 5-month-old diabetic and nondiabetic, wild-type and B1RB2R?/? mice, in vivo cardiac contractile function was determined by left-ventricular (LV) catheterization and echocardiography. Reactive oxygen species levels were measured by 2?-7?-dichlorofluorescein diacetate fluorescence. Mitochondrial function and ATP synthesis were determined in saponin-permeabilized cardiac fibers. LV systolic pressure and the peak rate of LV pressure rise and decline were decreased with diabetes but did not deteriorate further with loss of bradykinin signaling. Wall thinning and reduced ejection fractions in Akita mouse hearts were partially attenuated by B1RB2R deficiency, although other parameters of LV function were unaffected. Loss of bradykinin signaling did not increase fibrosis in Ins2Akita/+ diabetic mouse hearts. Mitochondrial dysfunction was not exacerbated by B1RB2R deficiency, nor was there any additional increase in tissue levels of reactive oxygen species. Thus, loss of bradykinin B2 receptor signaling does not abrogate the previously reported beneficial effect of inhibition of B1 receptor signaling. In conclusion, complete loss of bradykinin expression does not worsen cardiac function or increase myocardial fibrosis in diabetes. PMID:20501666

  18. Albumin stimulates renal tubular inflammation through an HSP70-TLR4 axis in mice with early diabetic nephropathy

    PubMed Central

    Jheng, Huei-Fen; Tsai, Pei-Jane; Chuang, Yi-Lun; Shen, Yi-Ting; Tai, Ting-An; Chen, Wen-Chung; Chou, Chuan-Kai; Ho, Li-Chun; Tang, Ming-Jer; Lai, Kuei-Tai A.; Sung, Junne-Ming; Tsai, Yau-Sheng

    2015-01-01

    ABSTRACT Increased urinary albumin excretion is not simply an aftermath of glomerular injury, but is also involved in the progression of diabetic nephropathy (DN). Whereas Toll-like receptors (TLRs) are incriminated in the renal inflammation of DN, whether and how albumin is involved in the TLR-related renal inflammatory response remains to be clarified. Here, we showed that both TLR2 and TLR4, one of their putative endogenous ligands [heat shock protein 70 (HSP70)] and nuclear factor-?B promoter activity were markedly elevated in the kidneys of diabetic mice. A deficiency of TLR4 but not of TLR2 alleviated albuminuria, tubulointerstitial fibrosis and inflammation induced by diabetes. The protection against renal injury in diabetic Tlr4?/? mice was associated with reduced tubular injuries and preserved cubilin levels, rather than amelioration of glomerular lesions. In vitro studies revealed that albumin, a stronger inducer than high glucose (HG), induced the release of HSP70 from proximal tubular cells. HSP70 blockade ameliorated albumin-induced inflammatory mediators. HSP70 triggered the production of inflammatory mediators in a TLR4-dependent manner. Moreover, HSP70 inhibition in vivo ameliorated diabetes-induced albuminuria, inflammatory response and tubular injury. Finally, we found that individuals with DN had higher levels of TLR4 and HSP70 in the dilated tubules than non-diabetic controls. Thus, activation of the HSP70-TLR4 axis, stimulated at least in part by albumin, in the tubular cell is a newly identified mechanism associated with induction of tubulointerstitial inflammation and aggravation of pre-existing microalbuminuria in the progression of DN. PMID:26398934

  19. Albumin stimulates renal tubular inflammation through an HSP70-TLR4 axis in mice with early diabetic nephropathy.

    PubMed

    Jheng, Huei-Fen; Tsai, Pei-Jane; Chuang, Yi-Lun; Shen, Yi-Ting; Tai, Ting-An; Chen, Wen-Chung; Chou, Chuan-Kai; Ho, Li-Chun; Tang, Ming-Jer; Lai, Kuei-Tai A; Sung, Junne-Ming; Tsai, Yau-Sheng

    2015-10-01

    Increased urinary albumin excretion is not simply an aftermath of glomerular injury, but is also involved in the progression of diabetic nephropathy (DN). Whereas Toll-like receptors (TLRs) are incriminated in the renal inflammation of DN, whether and how albumin is involved in the TLR-related renal inflammatory response remains to be clarified. Here, we showed that both TLR2 and TLR4, one of their putative endogenous ligands [heat shock protein 70 (HSP70)] and nuclear factor-?B promoter activity were markedly elevated in the kidneys of diabetic mice. A deficiency of TLR4 but not of TLR2 alleviated albuminuria, tubulointerstitial fibrosis and inflammation induced by diabetes. The protection against renal injury in diabetic Tlr4(-/-) mice was associated with reduced tubular injuries and preserved cubilin levels, rather than amelioration of glomerular lesions. In vitro studies revealed that albumin, a stronger inducer than high glucose (HG), induced the release of HSP70 from proximal tubular cells. HSP70 blockade ameliorated albumin-induced inflammatory mediators. HSP70 triggered the production of inflammatory mediators in a TLR4-dependent manner. Moreover, HSP70 inhibition in vivo ameliorated diabetes-induced albuminuria, inflammatory response and tubular injury. Finally, we found that individuals with DN had higher levels of TLR4 and HSP70 in the dilated tubules than non-diabetic controls. Thus, activation of the HSP70-TLR4 axis, stimulated at least in part by albumin, in the tubular cell is a newly identified mechanism associated with induction of tubulointerstitial inflammation and aggravation of pre-existing microalbuminuria in the progression of DN. PMID:26398934

  20. Podocyte-specific deletion of Rac1 leads to aggravation of renal injury in STZ-induced diabetic mice.

    PubMed

    Ishizaka, Masanori; Gohda, Tomohito; Takagi, Miyuki; Omote, Keisuke; Sonoda, Yuji; Oliva Trejo, Juan Alejandro; Asao, Rin; Hidaka, Teruo; Asanuma, Katsuhiko; Horikoshi, Satoshi; Tomino, Yasuhiko

    2015-11-20

    Rac1, a GTPase of the Rho subfamily, has a crucial role in cytoskeletal architecture, as well as the regulation of cell migration and growth. However, renal injury in mice with podocyte-specific deletion of Rac1 has yet to be elucidated fully due to conflicting findings. Herein, we identified a possible role for Rac1 in podocytes of streptozotocin- (STZ) induced diabetic mice. The urinary albumin/creatinine ratio (ACR) in the knockout (KO) group was significantly higher than that in the wild type (WT) group at any week of age. A more marked ACR increase was observed in STZ/KO group than STZ/WT group, although ACR did increase with weeks of age in both diabetic groups. The kidney sections from diabetic mice revealed a glomerular hypertrophy with mesangial expansion, but there was no appreciable difference in glomerular findings under a light microscope between STZ/WT and STZ/KO mice. However, an electron microscopy analysis revealed that regardless of the presence or absence of diabetes, both KO (KO and STZ/KO) groups had a higher rate of foot process effacement compared with both WT (WT and STZ/WT) groups. The expression levels of the slit diaphragm protein, podocin, was reduced with the induction of diabetes, and the levels in the STZ/KO group experienced a further reduction compared with the STZ/WT group. The number of WT1-positive cells in the STZ/KO group was more significantly decreased than that in the other three groups. In contrast, the numbers of cleaved caspase 3- and TUNEL-positive cells in the glomeruli of the STZ/KO group were more increased than those in the STZ/WT group. Thus, this study provides evidence that podocyte-specific deletion of Rac1 results in morphological alteration in podocytes, and that the induction of apoptosis or decreased expression of the slit diaphragm proteins by hyperglycemic stimuli are associated with the progression of diabetic nephropathy. PMID:26435502

  1. Characterization of the gut microbiota in leptin deficient obese mice - Correlation to inflammatory and diabetic parameters.

    PubMed

    Ellekilde, M; Krych, L; Hansen, C H F; Hufeldt, M R; Dahl, K; Hansen, L H; Sørensen, S J; Vogensen, F K; Nielsen, D S; Hansen, A K

    2014-04-01

    Gut microbiota have been implicated as a relevant factor in the development of type 2 diabetes mellitus (T2DM), and its diversity might be a cause of variation in animal models of T2DM. In this study, we aimed to characterise the gut microbiota of a T2DM mouse model with a long term vision of being able to target the gut microbiota to reduce the number of animals used in experiments. Male B6.V-Lep(ob)/J mice were characterized according to a number of characteristics related to T2DM, inflammation and gut microbiota. All findings were thereafter correlated to one another in a linear regression model. The total gut microbiota profile correlated to glycated haemoglobin, and high proportions of Prevotellaceae and Lachnospiraceae correlated to impaired or improved glucose intolerance, respectively. In addition, Akkermansia muciniphila disappeared with age as glucose intolerance worsened. A high proportion of regulatory T cells correlated to the gut microbiota and improved glucose tolerance. Furthermore, high levels of IL-10, IL-12 and TNF-? correlated to impaired glucose tolerance, blood glucose or glycated haemoglobin. The findings indicate that gut microbiota may contribute to variation in various disease read-outs in the B6.V-Lep(ob)/J model and considering them in both quality assurance and data evaluation for the B6.V-Lep(ob)/J model may have a reducing impact on the inter-individual variation. PMID:24556473

  2. Increased Autoimmune Diabetes in pIgR-Deficient NOD Mice Is Due to a "Hitchhiking" Interval that Refines the Genetic Effect of Idd5.4

    PubMed Central

    Simpfendorfer, Kim R.; Strugnell, Richard A.

    2015-01-01

    Selective breeding to introduce a gene mutation from one mouse strain onto the genetic background of another strain invariably produces “hitchhiking” (i.e. flanking) genomic intervals, which may independently affect a disease trait of interest. To investigate a role for the polymeric Ig receptor in autoimmune diabetes, a congenic nonobese diabetic (NOD) mouse strain was generated that harbors a Pigr null allele derived from C57BL/6 (B6) mice. These pIgR-deficient NOD mice exhibited increased serum IgA along with an increased diabetes incidence. However, the Pigr null allele was encompassed by a relatively large “hitchhiking” genomic interval that was derived from B6 mice and overlaps Idd5.4, a susceptibility locus for autoimmune diabetes. Additional congenic NOD mouse strains, harboring smaller B6-derived intervals, confirmed Idd5.4 independently of the other three known susceptibility loci on chromosome 1, and further localized Idd5.4 to an interval proximal to Pigr. Moreover, these congenic NOD mice showed that B6 mice harbor a more diabetogenic allele than NOD mice for this locus. The smallest B6-derived interval encompassing the Pigr null allele may, however, confer a small degree of protection against diabetes, but this protection appears to be dependent on the absence of the diabetogenic B6 allele for Idd5.4. This study provides another example of the potential hidden effects of “hitchhiking" genomic intervals and how such intervals can be used to localize disease susceptibility loci. PMID:25835383

  3. Dioscorea Extract (DA-9801) Modulates Markers of Peripheral Neuropathy in Type 2 Diabetic db/db Mice

    PubMed Central

    Moon, Eunjung; Lee, Sung Ok; Kang, Tong Ho; Kim, Hye Ju; Choi, Sang Zin; Son, Mi-Won; Kim, Sun Yeou

    2014-01-01

    The purpose of this study was to investigate the therapeutic effects of DA-9801, an optimized extract of Dioscorea species, on diabetic peripheral neuropathy in a type 2 diabetic animal model. In this study, db/db mice were treated with DA-9801 (30 and 100 mg/kg, daily, p.o.) for 12 weeks. DA-9801 reduced the blood glucose levels and increased the withdrawal latencies in hot plate tests. Moreover, it prevented nerve damage based on increased nerve conduction velocity and ultrastructural changes. Decrease of nerve growth factor (NGF) may have a detrimental effect on diabetic neuropathy. We previously reported NGF regulatory properties of the Dioscorea genus. In this study, DA-9801 induced NGF production in rat primary astrocytes. In addition, it increased NGF levels in the sciatic nerve and the plasma of type 2 diabetic animals. DA-9801 also increased neurite outgrowth and mRNA expression of Tieg1/Klf10, an NGF target gene, in PC12 cells. These results demonstrated the attenuation of diabetic peripheral neuropathy by oral treatment with DA-9801 via NGF regulation. DA-9801 is currently being evaluated in a phase II clinical study. PMID:25414776

  4. Leptin Deficiency Shifts Mast Cells toward Anti-Inflammatory Actions and Protects Mice from Obesity and Diabetes by Polarizing M2 Macrophages.

    PubMed

    Zhou, Yi; Yu, Xueqing; Chen, Huimei; Sjöberg, Sara; Roux, Joséphine; Zhang, Lijun; Ivoulsou, Al-Habib; Bensaid, Farid; Liu, Cong-Lin; Liu, Jian; Tordjman, Joan; Clement, Karine; Lee, Chih-Hao; Hotamisligil, Gokhan S; Libby, Peter; Shi, Guo-Ping

    2015-12-01

    Mast cells (MCs) contribute to the pathogenesis of obesity and diabetes. This study demonstrates that leptin deficiency slants MCs toward anti-inflammatory functions. MCs in the white adipose tissue (WAT) of lean humans and mice express negligible leptin. Adoptive transfer of leptin-deficient MCs expanded ex vivo mitigates diet-induced and pre-established obesity and diabetes in mice. Mechanistic studies show that leptin-deficient MCs polarize macrophages from M1 to M2 functions because of impaired cell signaling and an altered balance between pro- and anti-inflammatory cytokines, but do not affect T cell differentiation. Rampant body weight gain in ob/ob mice, a strain that lacks leptin, associates with reduced MC content in WAT. In ob/ob mice, genetic depletion of MCs exacerbates obesity and diabetes, and repopulation of ex vivo expanded ob/ob MCs ameliorates these diseases. PMID:26481668

  5. Heme Oxygenase-1 Prevents Cardiac Dysfunction in Streptozotocin-Diabetic Mice by Reducing Inflammation, Oxidative Stress, Apoptosis and Enhancing Autophagy

    PubMed Central

    Qiao, Yu; Zhou, Xiaoling; Wu, Guodong; Wang, Lujing; Peng, Yahui; Dong, Xingli; Huang, Hui; Si, Lining; Zhang, Xueying; Zhang, Lei; Li, Jihong; Wang, Wei; Zhou, Lingyun; Gao, Xu

    2013-01-01

    Heme oxygenase-1 (HO-1) has been implicated in cardiac dysfunction, oxidative stress, inflammation, apoptosis and autophagy associated with heart failure, and atherosclerosis, in addition to its recognized role in metabolic syndrome and diabetes. Numerous studies have presented contradictory findings about the role of HO-1 in diabetic cardiomyopathy (DCM). In this study, we explored the role of HO-1 in myocardial dysfunction, myofibril structure, oxidative stress, inflammation, apoptosis and autophagy using a streptozotocin (STZ)-induced diabetes model in mice systemically overexpressing HO-1 (Tg-HO-1) or mutant HO-1 (Tg-mutHO-1). The diabetic mouse model was induced by multiple peritoneal injections of STZ. Two months after injection, left ventricular (LV) function was measured by echocardiography. In addition, molecular biomarkers related to oxidative stress, inflammation, apoptosis and autophagy were evaluated using classical molecular biological/biochemical techniques. Mice with DCM exhibited severe LV dysfunction, myofibril structure disarray, aberrant cardiac oxidative stress, inflammation, apoptosis, autophagy and increased levels of HO-1. In addition, we determined that systemic overexpression of HO-1 ameliorated left ventricular dysfunction, myofibril structure disarray, oxidative stress, inflammation, apoptosis and autophagy in DCM mice. Furthermore, serine/threonine-specific protein kinase (Akt) and AMP-activated protein kinase (AMPK) phosphorylation is normally inhibited in DCM, but overexpression of the HO-1 gene restored the phosphorylation of these kinases to normal levels. In contrast, the functions of HO-1 in DCM were significantly reversed by overexpression of mutant HO-1. This study underlines the unique roles of HO-1, including the inhibition of oxidative stress, inflammation and apoptosis and the enhancement of autophagy, in the pathogenesis of DCM. PMID:24086665

  6. A novel MitoNEET ligand, TT01001, improves diabetes and ameliorates mitochondrial function in db/db mice.

    PubMed

    Takahashi, Takehiro; Yamamoto, Masashi; Amikura, Kazutoshi; Kato, Kozue; Serizawa, Takashi; Serizawa, Kanako; Akazawa, Daisuke; Aoki, Takumi; Kawai, Koji; Ogasawara, Emi; Hayashi, Jun-Ichi; Nakada, Kazuto; Kainoh, Mie

    2015-02-01

    The mitochondrial outer membrane protein mitoNEET is a binding protein of the insulin sensitizer pioglitazone (5-[[4-[2-(5-ethylpyridin-2-yl)ethoxy]phenyl]methyl]-1,3-thiazolidine-2,4-dione) and is considered a novel target for the treatment of type II diabetes. Several small-molecule compounds have been identified as mitoNEET ligands using structure-based design or virtual docking studies. However, there are no reports about their therapeutic potential in animal models. Recently, we synthesized a novel small molecule, TT01001 [ethyl-4-(3-(3,5-dichlorophenyl)thioureido)piperidine-1-carboxylate], designed on the basis of pioglitazone structure. In this study, we assessed the pharmacological properties of TT01001 in both in vitro and in vivo studies. We found that TT01001 bound to mitoNEET without peroxisome proliferator-activated receptor-? activation effect. In type II diabetes model db/db mice, TT01001 improved hyperglycemia, hyperlipidemia, and glucose intolerance, and its efficacy was equivalent to that of pioglitazone, without the pioglitazone-associated weight gain. Mitochondrial complex II + III activity of the skeletal muscle was significantly increased in db/db mice. We found that TT01001 significantly suppressed the elevated activity of the complex II + III. These results suggest that TT01001 improved type II diabetes without causing weight gain and ameliorated mitochondrial function of db/db mice. This is the first study that demonstrates the effects of a mitoNEET ligand on glucose metabolism and mitochondrial function in an animal disease model. These findings support targeting mitoNEET as a potential therapeutic approach for the treatment of type II diabetes. PMID:25503385

  7. Diminished Chondrogenesis and Enhanced Osteoclastogenesis in Leptin-Deficient Diabetic Mice (ob/ob) Impair Pathologic, Trauma-Induced Heterotopic Ossification.

    PubMed

    Agarwal, Shailesh; Loder, Shawn; Li, John; Brownley, Cameron; Peterson, Jonathan R; Oluwatobi, Eboda; Drake, James; Cholok, David; Ranganathan, Kavitha; Sung, Hsiao Hsin; Goulet, James; Li, Shuli; Levi, Benjamin

    2015-12-15

    Diabetic trauma patients exhibit delayed postsurgical wound, bony healing, and dysregulated bone development. However, the impact of diabetes on the pathologic development of ectopic bone or heterotopic ossification (HO) following trauma is unknown. In this study, we use leptin-deficient mice as a model for type 2 diabetes to understand how post-traumatic HO development may be affected by this disease process. Male leptin-deficient (ob/ob) or wild-type (C57BL/6 background) mice aged 6-8 weeks underwent 30% total body surface area burn injury with left hind limb Achilles tenotomy. Micro-CT (?CT) imaging showed significantly lower HO volumes in diabetic mice compared with wild-type controls (0.70 vs. 7.02?mm(3), P?mice showed evidence of HO resorption between weeks 5 and 9. Quantitative real time PCR (qRT-PCR) demonstrated high Vegfa levels in ob/ob mice, which was followed by disorganized vessel growth at 7 weeks. We noted diminished chondrogenic gene expression (SOX9) and diminished cartilage formation at 5 days and 3 weeks, respectively. Tartrate-resistant acid phosphatase stain showed increased osteoclast presence in normal native bone and pathologic ectopic bone in ob/ob mice. Our findings suggest that early diminished HO in ob/ob mice is related to diminished chondrogenic differentiation, while later bone resorption is related to osteoclast presence. PMID:26413838

  8. Dietary Wolfberry Ameliorates Retinal Structure Abnormalities in db/db Mice at the Early Stage of Diabetes

    PubMed Central

    Tang, Ling; Zhang, Yunong; Jiang, Yu; Willard, Lloyd; Ortiz, Edlin; Wark, Logan; Medeiros, Denis; Lin, Dingbo

    2011-01-01

    Hyperglycemia-linked oxidative stress and/or consequent endoplasmic reticulum stress are the causative factors of pathogenesis of diabetic retinopathy. Dietary bioactive components which mitigate oxidative stress may serve as potential chemopreventative agents to prevent or slow down the disease progression. Wolfberry is a traditional Asian fruit consumed for years to prevent aging eye diseases in Asian countries. Here we report that dietary wolfberry ameliorated mouse retinal abnormality at the early stage of type 2 diabetes in db/db mice. Male mice at 6 weeks of age were fed the control diet with or without 1 % (kCal) wolfberry for 8 weeks. Dietary wolfberry restored the thickness of the whole retina, in particular the inner nuclear layer and photoreceptor layer, and the integrity of retinal pigment epithelia (RPE), and the ganglion cell number in db/db mice. Western blotting of whole retinal cell lysates revealed that addition of wolfberry lowered expression of endoplasmic reticulum (ER) stress biomarkers BiP, PERK, ATF6, and caspase-12; and restored AMPK, thioredoxin, Mn SOD, and FOXO3? activities. To determine if our observations were due to the high contents of zeaxanthin and lutein in wolfberry additional studies using these carotenoids were conducted. Using the human adult diploid RPE cell line ARPE-19 we demonstrated that both zeaxanthin and lutein could mimic wolfberry preventive effect on activation of AMPK, thioredoxin, Mn SOD, FOXO3? activities, normalize cellular reactive oxygen species, and attenuate ER stress in ARPE-19 cells exposed to a high glucose challenge. The zeaxanthin preventive effect was abolished by siRNA knockdown of AMPK?. These results suggested that AMPK activation appeared to play a key role in upregulated expression of thioredoxin and Mn SOD, and mitigation of cellular oxidative stress and/or ER stress by wolfberry and zeaxanthin and/or lutein. Taken together, dietary wolfberry on retinal protection in diabetic mice is, at least partially, due to zeaxanthin and/or lutein. PMID:21750018

  9. Olive leaf down-regulates the oxidative stress and immune dysregulation in streptozotocin-induced diabetic mice.

    PubMed

    Park, Jung-Hyun; Jung, Ji-Hye; Yang, Jin-Young; Kim, Hyun-Sook

    2013-11-01

    Type 1 diabetes is an endocrinologic disorder characterized by uncontrolled glucose regulation and oxidative stress. Olive leaves have been studied extensively for their antioxidant activity and capacity to improve immune function. We hypothesized that olive leaf powder supplementation will be effective in inhibiting the oxidative stress and immune dysregulation in streptozotocin (STZ)-induced diabetic mice. Mice were assigned to 1 of 5 groups: control (C), STZ-induced diabetes (D), and STZ-induced diabetes supplemented with very low dose (VLOL), low dose (LOL), or high dose of olive leaf powder (HOL). Blood glucose in the VLOL and LOL groups was lower than that in the D group (P < .05). Insulin levels were increased in all experimental groups in comparison with that in the D group, (P < .05). Superoxide dismutase, glutathione peroxidase, and catalase activities were shown to decrease in the D group, whereas these were increased in the VLOL and LOL groups. Nitric oxide levels decreased in the VLOL and LOL groups, as compared with the D group. The messenger RNA expression levels of inducible nitric oxide synthase were significantly decreased in the VLOL and HOL groups, and interferon-? levels were significantly decreased in the liver of the VLOL, LOL, and HOL groups compared with the levels in the D group. Interleukin-17 levels were significantly decreased in the VLOL and HOL groups. Th1 and Th17 cytokine levels were increased in the D group but decreased in all the experimental groups. Th2 cytokine levels were increased in all olive leaf-supplemented groups compared with those in the D group. These results indicate a reduction in the levels of proinflammatory cytokines, suggesting that olive leaves have the potential to provide therapeutic inhibition of diabetic complications. PMID:24176234

  10. Hyperbaric oxygen therapy activates hypoxia-inducible factor 1 (HIF-1), which contributes to improved wound healing in diabetic mice.

    PubMed

    Sunkari, Vivekananda Gupta; Lind, Folke; Botusan, Ileana Ruxandra; Kashif, Abad; Liu, Zhao-Jun; Ylä-Herttuala, Seppo; Brismar, Kerstin; Velazquez, Omaida; Catrina, Sergiu-Bogdan

    2015-01-01

    Hyperbaric oxygen (HBO) therapy has been used as an adjunctive therapy for diabetic foot ulcers, although its mechanism of action is not completely understood. Recently, it has been shown that HBO mobilizes the endothelial progenitor cells (EPCs) from bone marrow that eventually will aggregate in the wound. However, the gathering of the EPCs in diabetic wounds is impaired because of the decreased levels of local stromal-derived factor-1? (SDF-1?). Therefore, we investigated the influence of HBO on hypoxia-inducible factor 1 (HIF-1), which is a central regulator of SDF-1? and is down-regulated in diabetic wounds. The effects of HBO on HIF-1? function were studied in human dermal fibroblasts, SKRC7 cells, and HIF-1? knock-out and wild-type mouse embryonic fibroblasts using appropriate techniques (Western blot, quantitative polymerase chain reaction, and luciferase hypoxia-responsive element reporter assay). Cellular proliferation was assessed using H(3) -thymidine incorporation assay. The effect of HIF in combination with HBOT was tested by inoculating stable HIF-1?-expressing adenovirus (Adv-HIF) into experimental wounds in db/db mice exposed to HBO. HBO activates HIF-1? at several levels by increasing both HIF-1? stability (by a non-canonical mechanism) and activity (as shown both by induction of relevant target genes and by a specific reporter assay). HIF-1? induction has important biological relevance because the induction of fibroblast proliferation in HBO disappears when HIF-1? is knocked down. Moreover, the local transfer of stable HIF-1?-expressing adenovirus (Adv-HIF) into experimental wounds in diabetic (db/db mice) animals has an additive effect on HBO-mediated improvements in wound healing. In conclusion, HBO stabilizes and activates HIF-1, which contributes to increased cellular proliferation. In diabetic animals, the local transfer of active HIF further improves the effects of HBO on wound healing. PMID:25532619

  11. Systemic alterations in the metabolome of diabetic NOD mice delineate increased oxidative stress accompanied by reduced inflammation and hypertriglyceremia.

    PubMed

    Fahrmann, Johannes; Grapov, Dmitry; Yang, Jun; Hammock, Bruce; Fiehn, Oliver; Bell, Graeme I; Hara, Manami

    2015-06-01

    Nonobese diabetic (NOD) mice are a commonly used model of type 1 diabetes (T1D). However, not all animals will develop overt diabetes despite undergoing similar autoimmune insult. In this study, a comprehensive metabolomic approach, consisting of gas chromatography time-of-flight (GC-TOF) mass spectrometry (MS), ultra-high-performance liquid chromatography-accurate mass quadruple time-of-flight (UHPLC-qTOF) MS and targeted UHPLC-tandem mass spectrometry-based methodologies, was used to capture metabolic alterations in the metabolome and lipidome of plasma from NOD mice progressing or not progressing to T1D. Using this multi-platform approach, we identified >1,000 circulating lipids and metabolites in male and female progressor and nonprogressor animals (n = 71). Statistical and multivariate analyses were used to identify age- and sex-independent metabolic markers, which best differentiated metabolic profiles of progressors and nonprogressors. Key T1D-associated perturbations were related with 1) increases in oxidation products glucono-?-lactone and galactonic acid and reductions in cysteine, methionine and threonic acid, suggesting increased oxidative stress; 2) reductions in circulating polyunsaturated fatty acids and lipid signaling mediators, most notably arachidonic acid (AA) and AA-derived eicosanoids, implying impaired states of systemic inflammation; 3) elevations in circulating triacylglyercides reflective of hypertriglyceridemia; and 4) reductions in major structural lipids, most notably lysophosphatidylcholines and phosphatidylcholines. Taken together, our results highlight the systemic perturbations that accompany a loss of glycemic control and development of overt T1D. PMID:25852003

  12. Antihyperglycemic Activity of Eucalyptus tereticornis in Insulin-Resistant Cells and a Nutritional Model of Diabetic Mice

    PubMed Central

    Guillén, Alis; Granados, Sergio; Rivas, Kevin Eduardo; Estrada, Omar; Echeverri, Luis Fernando; Balcázar, Norman

    2015-01-01

    Eucalyptus tereticornis is a plant used in traditional medicine to control diabetes, but this effect has not been proved scientifically. Here, we demonstrated through in vitro assays that E. tereticornis extracts increase glucose uptake and inhibit their production in insulin-resistant C2C12 and HepG2 cells, respectively. Furthermore, in a nutritional model using diabetic mice, the administration of ethyl acetate extract of E. tereticornis reduced fasting glycaemia, improved tolerance to glucose, and reduced resistance to insulin. Likewise, this extract had anti-inflammatory effects in adipose tissue when compared to control diabetic mice. Via bioguided assays and sequential purification of the crude extract, a triterpenoid-rich fraction from ethyl acetate extracts was shown to be responsible for the biological activity. Similarly, we identified the main compound responsible for the antihyperglycemic activity in this extract. This study shows that triterpenes found in E. tereticornis extracts act as hypoglycemic/antidiabetic compounds and contribute to the understanding of their use in traditional medicine. PMID:26366171

  13. siRNA-based spherical nucleic acids reverse impaired wound healing in diabetic mice by ganglioside GM3 synthase knockdown

    PubMed Central

    Randeria, Pratik S.; Seeger, Mark A.; Wang, Xiao-Qi; Wilson, Heather; Shipp, Desmond; Mirkin, Chad A.; Paller, Amy S.

    2015-01-01

    Spherical nucleic acid (SNA) gold nanoparticle conjugates (13-nm-diameter gold cores functionalized with densely packed and highly oriented nucleic acids) dispersed in Aquaphor have been shown to penetrate the epidermal barrier of both intact mouse and human skin, enter keratinocytes, and efficiently down-regulate gene targets. ganglioside-monosialic acid 3 synthase (GM3S) is a known target that is overexpressed in diabetic mice and responsible for causing insulin resistance and impeding wound healing. GM3S SNAs increase keratinocyte migration and proliferation as well as insulin and insulin-like growth factor-1 (IGF1) receptor activation under both normo- and hyperglycemic conditions. The topical application of GM3S SNAs (50 nM) to splinted 6-mm-diameter full-thickness wounds in diet-induced obese diabetic mice decreases local GM3S expression by >80% at the wound edge through an siRNA pathway and fully heals wounds clinically and histologically within 12 d, whereas control-treated wounds are only 50% closed. Granulation tissue area, vascularity, and IGF1 and EGF receptor phosphorylation are increased in GM3S SNA-treated wounds. These data capitalize on the unique ability of SNAs to naturally penetrate the skin and enter keratinocytes without the need for transfection agents. Moreover, the data further validate GM3 as a mediator of the delayed wound healing in type 2 diabetes and support regional GM3 depletion as a promising therapeutic direction. PMID:25902507

  14. siRNA-based spherical nucleic acids reverse impaired wound healing in diabetic mice by ganglioside GM3 synthase knockdown.

    PubMed

    Randeria, Pratik S; Seeger, Mark A; Wang, Xiao-Qi; Wilson, Heather; Shipp, Desmond; Mirkin, Chad A; Paller, Amy S

    2015-05-01

    Spherical nucleic acid (SNA) gold nanoparticle conjugates (13-nm-diameter gold cores functionalized with densely packed and highly oriented nucleic acids) dispersed in Aquaphor have been shown to penetrate the epidermal barrier of both intact mouse and human skin, enter keratinocytes, and efficiently down-regulate gene targets. ganglioside-monosialic acid 3 synthase (GM3S) is a known target that is overexpressed in diabetic mice and responsible for causing insulin resistance and impeding wound healing. GM3S SNAs increase keratinocyte migration and proliferation as well as insulin and insulin-like growth factor-1 (IGF1) receptor activation under both normo- and hyperglycemic conditions. The topical application of GM3S SNAs (50 nM) to splinted 6-mm-diameter full-thickness wounds in diet-induced obese diabetic mice decreases local GM3S expression by >80% at the wound edge through an siRNA pathway and fully heals wounds clinically and histologically within 12 d, whereas control-treated wounds are only 50% closed. Granulation tissue area, vascularity, and IGF1 and EGF receptor phosphorylation are increased in GM3S SNA-treated wounds. These data capitalize on the unique ability of SNAs to naturally penetrate the skin and enter keratinocytes without the need for transfection agents. Moreover, the data further validate GM3 as a mediator of the delayed wound healing in type 2 diabetes and support regional GM3 depletion as a promising therapeutic direction. PMID:25902507

  15. Antihyperglycemic Activity of Eucalyptus tereticornis in Insulin-Resistant Cells and a Nutritional Model of Diabetic Mice.

    PubMed

    Guillén, Alis; Granados, Sergio; Rivas, Kevin Eduardo; Estrada, Omar; Echeverri, Luis Fernando; Balcázar, Norman

    2015-01-01

    Eucalyptus tereticornis is a plant used in traditional medicine to control diabetes, but this effect has not been proved scientifically. Here, we demonstrated through in vitro assays that E. tereticornis extracts increase glucose uptake and inhibit their production in insulin-resistant C2C12 and HepG2 cells, respectively. Furthermore, in a nutritional model using diabetic mice, the administration of ethyl acetate extract of E. tereticornis reduced fasting glycaemia, improved tolerance to glucose, and reduced resistance to insulin. Likewise, this extract had anti-inflammatory effects in adipose tissue when compared to control diabetic mice. Via bioguided assays and sequential purification of the crude extract, a triterpenoid-rich fraction from ethyl acetate extracts was shown to be responsible for the biological activity. Similarly, we identified the main compound responsible for the antihyperglycemic activity in this extract. This study shows that triterpenes found in E. tereticornis extracts act as hypoglycemic/antidiabetic compounds and contribute to the understanding of their use in traditional medicine. PMID:26366171

  16. Vascular Mechanics in Decellularized Aortas and Coronary Resistance Microvessels in Type 2 Diabetic db/db Mice.

    PubMed

    Anghelescu, Mircea; Tonniges, Jeffrey R; Calomeni, Ed; Shamhart, Patricia E; Agarwal, Gunjan; Gooch, Keith J; Trask, Aaron J

    2015-11-01

    We previously reported differences in stiffness between macro- and micro-vessels in type 2 diabetes (T2DM). The aim of this study was to define the mechanical properties of the ECM independent of vascular cells in coronary resistance micro-vessels (CRMs) and macro-vessels (aorta) in control Db/db and T2DM db/db mice. Passive vascular remodeling and mechanics were measured in both intact and decellularized CRMs and aortas from 0 to 125 mmHg. We observed no differences in intact control and diabetic aortic diameters, wall thicknesses, or stiffnesses (p > 0.05). Aortic decellularization caused a significant increase in internal and external diameters and incremental modulus over a range of pressures that occurred to a similar degree in T2DM. Differences in aortic diameters due to decellularization occurred at lower pressures (0-75 mmHg) and converged with intact aortas at higher, physiological pressures (100-125 mmHg). In contrast, CRM decellularization caused increased internal diameter and incremental modulus only in the db/db mice, but unlike the aorta, the intact and decellularized CRM curves were more parallel. These data suggest that (1) micro-vessels may be more sensitive to early adverse consequences of diabetes than macro-vessels and (2) the ECM is a structural limit in aortas, but not CRMs. PMID:25986954

  17. Role of Micro RNA-205 in Promoting Visceral Adiposity of NZ10 Mice with Polygenic Susceptibility for Type 2 Diabetes

    PubMed Central

    Adi, Nikhil; Adi, Jennipher; Cesar, Liliana; Kurlansky, Paul; Agatston, Arthur; Webster, Keith A

    2015-01-01

    Scope To characterize diet-dependent miRNA profiles and their targets in the visceral adipose of mice with polygenic susceptibility to type 2 diabetes. Methods and results Six-week NONcNZO10/LtJ (NZ10) and control SWR/J mice were subjected to high protein-fish oil or control diets for 19 weeks and micro-RNA microarray analyses were implemented on visceral adipose RNA. We found that 27 miRNAs were significantly induced and 10 significantly repressed in the VA of obese NZ10 mice compared with controls. 12 selected regulated miRNAs were confirmed by RT-PCR based on the microarray data and we demonstrated that the expression of these miRNAs remained unaltered in the VA of control SWR mice. To assess the possible functional roles of miRNAs in adipogenesis, we also analyzed their expression in 3T3-L1 cells during growth and differentiation. This revealed that suppression of miRNA-205 alone correlated selectively with increased cell proliferation and lipid formation of adipocytes. Conclusion Diet and genetics control the expression of obesity-regulated miRNAs in the visceral adipose of NZ10 mice.

  18. Mammalian Target of Rapamycin (mTOR) Inhibition with Rapamycin Improves Cardiac Function in Type 2 Diabetic Mice

    PubMed Central

    Das, Anindita; Durrant, David; Koka, Saisudha; Salloum, Fadi N.; Xi, Lei; Kukreja, Rakesh C.

    2014-01-01

    Elevated mammalian target of rapamycin (mTOR) signaling contributes to the pathogenesis of diabetes, with increased morbidity and mortality, mainly because of cardiovascular complications. Because mTOR inhibition with rapamycin protects against ischemia/reperfusion injury, we hypothesized that rapamycin would prevent cardiac dysfunction associated with type 2 diabetes (T2D). We also investigated the possible mechanisms and novel protein targets involved in rapamycin-induced preservation of cardiac function in T2D mice. Adult male leptin receptor null, homozygous db/db, or wild type mice were treated daily for 28 days with vehicle (5% DMSO) or rapamycin (0.25 mg/kg, intraperitoneally). Cardiac function was monitored by echocardiography, and protein targets were identified by proteomics analysis. Rapamycin treatment significantly reduced body weight, heart weight, plasma glucose, triglyceride, and insulin levels in db/db mice. Fractional shortening was improved by rapamycin treatment in db/db mice. Oxidative stress as measured by glutathione levels and lipid peroxidation was significantly reduced in rapamycin-treated db/db hearts. Rapamycin blocked the enhanced phosphorylation of mTOR and S6, but not AKT in db/db hearts. Proteomic (by two-dimensional gel and mass spectrometry) and Western blot analyses identified significant changes in several cytoskeletal/contractile proteins (myosin light chain MLY2, myosin heavy chain 6, myosin-binding protein C), glucose metabolism proteins (pyruvate dehydrogenase E1, PYGB, Pgm2), and antioxidant proteins (peroxiredoxin 5, ferritin heavy chain 1) following rapamycin treatment in db/db heart. These results show that chronic rapamycin treatment prevents cardiac dysfunction in T2D mice, possibly through attenuation of oxidative stress and alteration of antioxidants and contractile as well as glucose metabolic protein expression. PMID:24371138

  19. Altered metabolic incorporation of fucose and leucine into PNS myelin of 25-week-old diabetic (C57BL/Ks (db/db)) mice: effects of untreated diabetes on nerve metabolism

    SciTech Connect

    Chez, M.G.; Peterson, R.G.

    1983-04-01

    Sciatic nerves of 25-week-old genetically diabetic (C57BL/Ks (db/db)) mice and their litter-mate controls were removed, and their metabolic incorporation of (/sup 3/H)fucose and (/sup 14/C)leucine into myelin was studied in vitro. Untreated diabetic animals showed significant increases (p less than 0.05) in the fucose/leucine incorporation into myelin when compared to values found for their litter-mates. These results correlated well with previous experiments performed on alloxan or streptozotocin-diabetic rats and thus show the in vitro incubation procedure to be a good indicator of altered metabolic conditions in peripheral nerves due to diabetes mellitus. The resulting ratio increases seen in diabetic animals is at variance with the decrease in ratios found in animals undergoing typical Wallerian degeneration. These results suggest that different metabolic processes operate in untreated diabetics than in normals or in those undergoing other degenerative nerve processes.

  20. Improvement of hyperglycaemia and metabolic syndromes in type 2 diabetic KKAy mice by oral treatment with [meso-tetrakis(4-sulfonatophenyl) porphyrinato]oxovanadium(IV)(4-) complex.

    PubMed

    Saha, Tapan Kumar; Yoshikawa, Yutaka; Sakurai, Hiromu

    2007-03-01

    Recently, we reported that [meso-tetrakis(4-sulfonatophenyl)porphyrinato]oxovanadium(IV)(4-), VO(tpps), shows in-vitro insulin-mimetic and in-vivo anti-diabetic activity in streptozotocin (STZ)-induced type 1 diabetic mice. This result prompted us to examine its ability in type 2 diabetic model KKA(y) mice with insulin resistance. We studied the in-vivo anti-diabetic activity of VO(tpps), compared with that of vanadium(IV) oxide sulfate, VS, as control. Both compounds were orally administered at doses of 5-10 mg (0.1-0.2 mmol) V/kg body weight to the KKA(y) mice for 28 days. VO(tpps) normalized the hyperglycaemia within 15 days, while VS lowered the blood glucose concentration only by a small degree. In addition, metabolic syndromes characterized by insulin and leptin resistance were significantly improved in VO(tpps)-treated KKA(y) mice compared with those treated with VS. The improvement in diabetes was validated by oral glucose tolerance test and decrease in HbA(1c) concentration. Based on these observations, VO(tpps) is proposed to be an orally active oxovanadium(IV)-porphyrin complex for treating not only type 2 diabetes but also metabolic syndromes in animals. PMID:17331348

  1. Anti-diabetic and hypolipidemic effects of Sargassum yezoense in db/db mice

    SciTech Connect

    Kim, Su-Nam; Lee, Woojung; Bae, Gyu-Un; Research Center for Cell Fate Control, Sookmyung Women's University, Seoul 140-742 ; Kim, Yong Kee

    2012-08-10

    Highlights: Black-Right-Pointing-Pointer Sargassum yezoense (SY) treatment improved glucose and lipid impairment in vivo. Black-Right-Pointing-Pointer This pharmacological action is associated with PPAR{alpha}/{gamma} dual activation. Black-Right-Pointing-Pointer It decreases the expression of G6Pase for gluconeogenesis in liver. Black-Right-Pointing-Pointer It increases the expression of UCP3 for lipid metabolism in adipose tissue. Black-Right-Pointing-Pointer There are no significant side effects such as body weight gain and hepatomegaly. -- Abstract: Peroxisome proliferator-activated receptors (PPARs) have been considered to be desirable targets for metabolic syndrome, even though their specific agonists have several side effects including body weight gain, edema and tissue failure. Previously, we have reported in vitro effects of Sargassum yezoense (SY) and its ingredients, sargaquinoic acid (SQA) and sargahydroquinoic acid (SHQA), on PPAR{alpha}/{gamma} dual transcriptional activation. In this study, we describe in vivo pharmacological property of SY on metabolic disorders. SY treatment significantly improved glucose and lipid impairment in db/db mice model. More importantly, there are no significant side effects such as body weight gain and hepatomegaly in SY-treated animals, indicating little side effects of SY in liver and lipid metabolism. In addition, SY led to a decrease in the expression of G6Pase for gluconeogenesis in liver responsible for lowering blood glucose level and an increase in the expression of UCP3 in adipose tissue for the reduction of total and LDL-cholesterol level. Altogether, our data suggest that SY would be a potential therapeutic agent against type 2 diabetes and related metabolic disorders by ameliorating the glucose and lipid metabolism.

  2. Oral Administration of Recombinant Lactococcus lactis Expressing HSP65 and Tandemly Repeated P277 Reduces the Incidence of Type I Diabetes in Non-Obese Diabetic Mice

    PubMed Central

    Ma, Yanjun; Liu, Jingjing; Hou, Jing; Dong, Yuankai; Lu, Yong; Jin, Liang; Cao, Rongyue; Li, Taiming; Wu, Jie

    2014-01-01

    Diabetes mellitus type 1 (DM1) is an autoimmune disease that gradually destroys insulin-producing beta-cells. We have previously reported that mucosal administration of fusion protein of HSP65 with tandem repeats of P277 (HSP65-6P277) can reduce the onset of DM1 in non-obese diabetic (NOD) mice. To deliver large amounts of the fusion protein and to enhance long-term immune tolerance effects, in the present study, we investigated the efficacy of using orally administrated L. lactis expressing HSP65-6P277 to reduce the incidence of DM1 in NOD mice. L. lactis strain NZ9000 was engineered to express HSP65-6P277 either constitutively or by nisin induction. After immunization via gavage with the recombinant L. lactis strains to groups of 4-week old female NOD mice for 36 weeks, we observed that oral administration of recombinant L. Lactis resulted in the prevention of hyperglycemia, improved glucose tolerance and reduced insulitis. Immunologic analysis showed that treatment with recombinant L. lactis induced HSP65- and P277- specific T cell immuno-tolerance, as well as antigen-specific proliferation of splenocytes. The results revealed that the DM1-preventing function was in part caused by a reduction in the pro-inflammatory cytokine IFN-? and an increase in the anti-inflammatory cytokine IL-10. Orally administered recombinant L. lactis delivering HSP65-6P277 may be an effective therapeutic approach in preventing DM1. PMID:25157497

  3. A Novel TGR5 Activator WB403 Promotes GLP-1 Secretion and Preserves Pancreatic ?-Cells in Type 2 Diabetic Mice

    PubMed Central

    Wang, Tongtong; You, Panpan; Zhao, Yongliang; Yang, Yiqing; Wang, Xin; Luo, Jian; Chen, Yihua; Liu, Mingyao; Chen, Huaqing

    2015-01-01

    The G protein-coupled receptor TGR5 is a membrane receptor for bile acids. Its agonism increases energy expenditure and controls blood glucose through secretion of glucagon-like peptide-1 in enteroendocrine cells. In this study, we explored the therapeutic potential of WB403, a small compound activating TGR5 which was identified by combining TGR5 targeted luciferase assay and active GLP-1 assay, in treating type 2 diabetes. After confirmation of TGR5 and GLP-1 stimulating activities in various cell systems, WB403 was examined in oral glucose tolerance test, and tested on different mouse models of type 2 diabetes for glycemic control and pancreatic ?-cell protection effect. As a result, WB403 exhibited a moderate TGR5 activation effect while promoting GLP-1 secretion efficiently. Interestingly, gallbladder filling effect, which was reported for some known TGR5 agonists, was not detected in this novel compound. In vivo results showed that WB403 significantly improved glucose tolerance and decreased fasting blood glucose, postprandial blood glucose and HbA1c in type 2 diabetic mice. Further analysis revealed that WB403 increased pancreatic ?-cells and restored the normal distribution pattern of ?-cell and ?-cell in islets. These findings demonstrated that TGR5 activator WB403 effectively promoted GLP-1 release, improved hyperglycemia and preserved the mass and function of pancreatic ?-cells, whereas it did not show a significant side effect on gallbladder. It may represent a promising approach for future type 2 diabetes mellitus drug development. PMID:26208278

  4. CXCL13 blockade disrupts B lymphocyte organization in tertiary lymphoid structures without altering B cell receptor bias or preventing diabetes in nonobese diabetic mice.

    PubMed

    Henry, Rachel A; Kendall, Peggy L

    2010-08-01

    Lymphocytes that invade nonlymphoid tissues often organize into follicle-like structures known as tertiary lymphoid organs (TLOs). These structures resemble those found in spleen or lymph nodes, but their function is unknown. TLOs are recognized in many autoimmune diseases, including the NOD mouse model of type 1 diabetes. In some cases, TLOs have been associated with the B lymphocyte chemoattractant, CXCL13. Studies presented in this article show that CXCL13 is present in inflamed islets of NOD mice. Ab blockade of this chemokine unraveled B lymphocyte organization in islet TLOs, without reducing their proportion in the islets. These chaotic milieus contained B lymphocytes with the same distinct repertoire of B cell receptors as those found in mice with well-organized structures. Somatic hypermutation, associated with T-B interactions, was not impaired in these disorganized insulitis lesions. Finally, loss of B lymphocyte organization in islets did not provide disease protection. Thus, B lymphocytes infiltrating islets in NOD mice do not require the morphology of secondary lymphoid tissues to support their role in disease. PMID:20574003

  5. Altered clock gene expression and vascular smooth muscle diurnal contractile variations in type 2 diabetic db/db mice

    PubMed Central

    Su, Wen; Xie, Zhongwen; Guo, Zhenheng; Duncan, Marilyn J.; Lutshumba, Jenny

    2012-01-01

    This study was designed to determine whether the 24-h rhythms of clock gene expression and vascular smooth muscle (VSM) contractile responses are altered in type 2 diabetic db/db mice. Control and db/db mice were euthanized at 6-h intervals throughout the day. The aorta, mesenteric arteries, heart, kidney, and brain were isolated. Clock and target gene mRNA levels were determined by either real-time PCR or in situ hybridization. Isometric contractions were measured in isolated aortic helical strips, and pressor responses to an intravenous injection of vasoconstrictors were determined in vivo using radiotelemetry. We found that the 24-h mRNA rhythms of the following genes were suppressed in db/db mice compared with control mice: the clock genes period homolog 1/2 (Per1/2) and cryptochrome 1/2 (Cry1/2) and their target genes D site albumin promoter-binding protein (Dbp) and peroxisome proliferator-activated receptor-? (Pparg) in the aorta and mesenteric arteries; Dbp in the heart; Per1, nuclear receptor subfamily 1, group D, member 1 (Rev-erba), and Dbp in the kidney; and Per1 in the suprachiasmatic nucleus. The 24-h contractile variations in response to phenylephrine (?1-agonist), ANG II, and high K+ were significantly altered in the aortas from db/db mice compared with control mice. The diurnal variations of the in vivo pressor responses to phenylephrine and ANG II were lost in db/db mice. Moreover, the 24-h mRNA rhythms of the contraction-related proteins Rho kinase 1/2, PKC-potentiated phosphatase inhibitory protein of 17 kDa, calponin-3, tropomyosin-1/2, and smooth muscle protein 22-? were suppressed in db/db mice compared with control mice. Together, our data demonstrated that the 24-h rhythms of clock gene mRNA, mRNA levels of several contraction-related proteins, and VSM contraction were disrupted in db/db mice, which may contribute to the disruption of their blood pressure circadian rhythm. PMID:22140039

  6. Ectopic expression of the agouti gene in transgenic mice causes obesity, features of type II diabetes, and yellow fur

    SciTech Connect

    Klebig, M.L.; Woychik, R.P.; Wilkinson, J.E.; Geisler, J.G. |

    1995-05-23

    Mice that carry the lethal yellow (A{sup y}) or viable yellow (A{sup vy}) mutation, two dominant mutations of the agouti (a) gene in mouse chromosome 2, exhibit a phenotype that includes yellow fur, marked obesity, a form of type II diabetes associated with insulin resistance, and an increased susceptibility to tumor development. Molecular analyses of these and several other dominant {open_quotes}obese yellow{close_quotes} a-locus mutations suggested that ectopic expression of the normal agouti protein gives rise to this complex pleiotropic phenotype. We have now tested this hypothesis directly by generating transgenic mice that ectopically express an agouti cDNA clone encoding the normal agouti protein in all tissues examined. Transgenic mice of both sexes have yellow fur, become obese, and develop hyperinsulinemia. In addition, male transgenic mice develop hyperglycemia by 12-20 weeks of age. These results demonstrate conclusively that the ectopic agouti expression is responsible for most, if not all, of the phenotypic traits of the dominant, obese yellow mutants. 42 refs., 5 figs.

  7. Maternal supplementation of diabetic mice with thymoquinone protects their offspring from abnormal obesity and diabetes by modulating their lipid profile and free radical production and restoring lymphocyte proliferation via PI3K/AKT signaling

    PubMed Central

    2013-01-01

    Background Epidemiological studies have shown that the offspring of mothers who experience diabetes mellitus during pregnancy are seven times more likely to develop health complications than the offspring of mothers who do not suffer from diabetes during pregnancy. The present study was designed to investigate whether supplementation of streptozotocin (STZ)-induced diabetic pregnant mice with thymoquinone (TQ) during pregnancy and lactation improves the risk of developing diabetic complications acquired by their offspring. Methods Three groups of pregnant female mice were used: non-diabetic control dams (CD), diabetic dams (DD), and diabetic dams supplemented with TQ (DD?+?TQ) during pregnancy and lactation (n?=?10 female mice in each group). Results Our data demonstrated a marked decrease in the number of neonates born to DD, and these neonates showed a marked increase in their mean body weight (macrosomic pups) compared to those born to CD and DD?+?TQ. The induction of diabetes during pregnancy and lactation resulted in macrosomic pups with several postpartum complications, such as a marked increase in their levels of blood glucose, free radicals, plasma pro-inflammatory cytokines (IL-1?, IL-6, and TNF-?), and lipids, and a tendency toward abnormal obesity compared to the offspring of CD. By contrast, macrosomic offspring born to DD exhibited a marked reduction in plasma cytokine levels (IL-2, -4 and -7), an obvious reduction in the number of circulating lymphocytes, decreased proliferation of superantigen (SEB)-stimulated lymphocytes and aberrant AKT phosphorylation. Interestingly, the supplementation of DD with TQ during pregnancy and lactation had an obvious and significant effect on the number and mean body weight of neonates. Furthermore, TQ significantly restored the levels of blood glucose, insulin, free radicals, plasma cytokines, and lipids as well as lymphocyte proliferation in the offspring. Conclusions Our data suggest that the nutritional supplementation of DD with the natural antioxidant TQ during pregnancy and lactation protects their offspring from developing diabetic complications and preserves an efficient lymphocyte immune response later in life. PMID:23506302

  8. Danhong Promotes Angiogenesis in Diabetic Mice after Critical Limb Ischemia by Activation of CSE-H 2 S-VEGF Axis.

    PubMed

    Wu, Feng; He, Zhiqing; Ding, Ru; Huang, Zhigang; Jiang, Qixia; Cui, Haiming; Lin, Yi; Huang, Shuaibo; Dai, Xianliang; Zhang, Jiayou; Wu, Zonggui; Liang, Chun

    2015-01-01

    The aim of this paper is to investigate effect and mechanism of Danhong injection (DH) on angiogenesis in the diabetic hind limb ischemia mouse model. Thirty diabetic hind limb ischemic model mice and ten normal mice, established by intraperitoneal (i.p.) injection of streptozotocin (STZ) or PBS and ligation/excision of femoral artery, and then twenty diabetic hind limb ischemic model mice of all were evenly randomized to saline (control, n = 10) and DH i.p. injection (2?mL/kg weight for 7 days, n = 10) groups. Limb perfusion recovery and femoral blood hydrogen sulfide (H2S) and vessel regeneration and lower limb vascular endothelial growth factor (VEGF)/cystathionine ?-lyase (CSE) expression were evaluated during intervention and after euthanasia, respectively. DH i.p. increased ischemic limb perfusion and promoted collateral circulation generation without decreasing blood glucose level. Increased local CSE-H2S-VEGF expression contributed to beneficial effects of DH injection. In conclusion, activation of local CSE-H2S-VEGF axis might participate in proangiogenesis effects of DH injection in diabetic hind limb ischemia model mice, suggesting a potential therapy for diabetic patients with critical limb ischemia. PMID:26491459

  9. Danhong Promotes Angiogenesis in Diabetic Mice after Critical Limb Ischemia by Activation of CSE-H2S-VEGF Axis

    PubMed Central

    Wu, Feng; He, Zhiqing; Ding, Ru; Huang, Zhigang; Jiang, Qixia; Cui, Haiming; Lin, Yi; Huang, Shuaibo; Dai, Xianliang; Zhang, Jiayou; Wu, Zonggui; Liang, Chun

    2015-01-01

    The aim of this paper is to investigate effect and mechanism of Danhong injection (DH) on angiogenesis in the diabetic hind limb ischemia mouse model. Thirty diabetic hind limb ischemic model mice and ten normal mice, established by intraperitoneal (i.p.) injection of streptozotocin (STZ) or PBS and ligation/excision of femoral artery, and then twenty diabetic hind limb ischemic model mice of all were evenly randomized to saline (control, n = 10) and DH i.p. injection (2?mL/kg weight for 7 days, n = 10) groups. Limb perfusion recovery and femoral blood hydrogen sulfide (H2S) and vessel regeneration and lower limb vascular endothelial growth factor (VEGF)/cystathionine ?-lyase (CSE) expression were evaluated during intervention and after euthanasia, respectively. DH i.p. increased ischemic limb perfusion and promoted collateral circulation generation without decreasing blood glucose level. Increased local CSE-H2S-VEGF expression contributed to beneficial effects of DH injection. In conclusion, activation of local CSE-H2S-VEGF axis might participate in proangiogenesis effects of DH injection in diabetic hind limb ischemia model mice, suggesting a potential therapy for diabetic patients with critical limb ischemia. PMID:26491459

  10. Adipose Tissue-Derived Mesenchymal Stem Cells Exert In Vitro Immunomodulatory and Beta Cell Protective Functions in Streptozotocin-Induced Diabetic Mice Model

    PubMed Central

    Rahavi, Hossein; Hashemi, Seyed Mahmoud; Soleimani, Masoud; Mohammadi, Jamal; Tajik, Nader

    2015-01-01

    Regenerative and immunomodulatory properties of mesenchymal stem cells (MSCs) might be applied for type 1 diabetes mellitus (T1DM) treatment. Thus, we proposed in vitro assessment of adipose tissue-derived MSCs (AT-MSCs) immunomodulation on autoimmune response along with beta cell protection in streptozotocin- (STZ-) induced diabetic C57BL/6 mice model. MSCs were extracted from abdominal adipose tissue of normal mice and cultured to proliferate. Diabetic mice were prepared by administration of multiple low-doses of streptozotocin. Pancreatic islets were isolated from normal mice and splenocytes prepared from normal and diabetic mice. Proliferation, cytokine production, and insulin secretion assays were performed in coculture experiments. AT-MSCs inhibited splenocytes proliferative response to specific (islet lysate) and nonspecific (PHA) triggers in a dose-dependent manner (P < 0.05). Decreased production of proinflammatory cytokines, such as IFN-?, IL-2, and IL-17, and increased secretion of regulatory cytokines such as TGF-?, IL-4, IL-10, and IL-13 by stimulated splenocytes were also shown in response to islet lysate or PHA stimulants (P < 0.05). Finally, we demonstrated that AT-MSCs could effectively sustain viability as well as insulin secretion potential of pancreatic islets in the presence of reactive splenocytes (P < 0.05). In conclusion, it seems that MSCs may provide a new horizon for T1DM cell therapy and islet transplantation in the future. PMID:25893202

  11. Pentoxifylline aggravates fatty liver in obese and diabetic ob/ob mice by increasing intestinal glucose absorption and activating hepatic lipogenesis

    PubMed Central

    Massart, J; Robin, MA; Noury, F; Fautrel, A; Lettéron, P; Bado, A; Eliat, PA; Fromenty, B

    2012-01-01

    BACKGROUND AND PURPOSE Pentoxifylline is in clinical trials for non-alcoholic fatty liver disease and diabetic nephropathy. Metabolic and hepatic effects of pentoxifylline were assessed in a murine model of obesity and type 2 diabetes. EXPERIMENTAL APPROACH Pentoxifylline (100 mg·kg?1·day?1) was administered for 4 days or 3 weeks in lean and obese/diabetic ob/ob mice. Plasma lipids, glucose, other metabolites and relevant enzymes were measured by standard assays. Hepatic lipids in vivo were assessed with magnetic resonance spectroscopy and by histology. Hepatic extracts were also analysed with RT-PCR and Western blotting. KEY RESULTS Four days of pentoxifylline treatment slightly increased liver lipids in ob/ob mice. After 3 weeks, pentoxifylline exacerbated fatty liver and plasma transaminases in ob/ob mice but did not induce liver steatosis in lean mice. Plasma glucose was highest in fed, but not fasted, ob/ob mice treated with pentoxifylline. During the first 10 min of an oral glucose tolerance test, blood glucose increased more rapidly in pentoxifylline-treated mice. Jejunal expression of glucose transporter 2 isoform was increased in pentoxifylline-treated obese mice. Hepatic activity of carbohydrate response element binding protein (ChREBP) increased after pentoxifylline in ob/ob, but not lean, mice. Hepatic expression of lipogenic enzymes was highest in pentoxifylline-treated ob/ob mice. However, pentoxifylline reduced markers of oxidative stress and inflammation in ob/ob liver. CONCLUSION AND IMPLICATIONS Pentoxifylline exacerbated fatty liver in ob/ob mice through enhanced intestinal glucose absorption, increased postprandial glycaemia and activation of hepatic lipogenesis. Long-term treatment with pentoxifylline could worsen fatty liver in some patients with pre-existing hyperglycaemia. PMID:21740407

  12. Evaluation of Effects of Chinese Prescription Kangen-karyu on Diabetes-Induced Alterations such as Oxidative Stress and Apoptosis in the Liver of Type 2 Diabetic db/db Mice

    PubMed Central

    Park, Chan Hum; Noh, Jeong Sook; Okamoto, Takuya; Park, Jong Cheol; Yokozawa, Takako

    2012-01-01

    The present study was conducted to examine whether Kangen-karyu has an ameliorative effect on diabetes-induced alterations such as oxidative stress and apoptosis in the liver of type 2 diabetic db/db mice. Kangen-karyu (100 or 200?mg/kg body weight/day, p.o.) was administered every day for 18 weeks to db/db mice and its effect was compared with vehicle-treated db/db and m/m mice. The administration of Kangen-karyu decreased the elevated serum glucose and leptin concentrations in db/db mice, and reduced the increased oxidative biomarkers including the generation of reactive oxygen species and lipid peroxidation in the liver. The db/db mice exhibited the upregulation of nicotinamide adenine dinucleotide phosphate oxidase subunits, NF-E2-related factor 2, heme oxygenase-1, nuclear factor-kappa B, cyclooxygenase-2, and inducible nitric oxide synthase levels in the liver; however, Kangen-karyu treatment significantly reduced those expressions. Moreover, the augmented expressions of apoptosis-related proteins, Bax, cytochrome c, c-Jun N-terminal kinase (JNK), phosphor-JNK, AP-1, and caspase-3, were downregulated by Kangen-karyu administration. Hematoxylin-eosin staining showed that the increased hepatocellular damage in the liver of db/db mice improved by Kangen-karyu administration. Our findings support the therapeutic evidence for Kangen-karyu ameliorating the development of diabetic hepatic complications via regulating oxidative stress and apoptosis. PMID:22969821

  13. Molecular pathway alterations in CD4 T-cells of nonobese diabetic (NOD) mice in the preinsulitis phase of autoimmune diabetes

    PubMed Central

    Kakoola, Dorothy N.; Curcio-Brint, Anita; Lenchik, Nataliya I.; Gerling, Ivan C.

    2014-01-01

    Type 1 diabetes (T1D) is a multigenic disease caused by T-cell mediated destruction of the insulin producing pancreatic islet ß-cells. The earliest sign of islet autoimmunity in NOD mice, islet leukocytic infiltration or insulitis, is obvious at around 5 weeks of age. The molecular alterations that occur in T cells prior to insulitis and that may contribute to T1D development are poorly understood. Since CD4 T-cells are essential to T1D development, we tested the hypothesis that multiple genes/molecular pathways are altered in these cells prior to insulitis. We performed a genome-wide transcriptome and pathway analysis of whole, untreated CD4 T-cells from 2, 3, and 4 week-old NOD mice in comparison to two control strains (NOR and C57BL/6). We identified many differentially expressed genes in the NOD mice at each time point. Many of these genes (herein referred to as NOD altered genes) lie within known diabetes susceptibility (insulin-dependent diabetes, Idd) regions, e.g. two diabetes resistant loci, Idd27 (tripartite motif-containing family genes) and Idd13 (several genes), and the CD4 T-cell diabetogenic activity locus, Idd9/11 (2 genes, KH domain containing, RNA binding, signal transduction associated 1 and protein tyrosine phosphatase 4a2). The biological processes associated with these altered genes included, apoptosis/cell proliferation and metabolic pathways (predominant at 2 weeks); inflammation and cell signaling/activation (predominant at 3 weeks); and innate and adaptive immune responses (predominant at 4 weeks). Pathway analysis identified several factors that may regulate these abnormalities: eight, common to all 3 ages (interferon regulatory factor 1, hepatic nuclear factor 4, alpha, transformation related protein 53, BCL2-like 1 (lies within Idd13), interferon gamma, interleukin 4, interleukin 15, and prostaglandin E2); and two each, common to 2 and 4 weeks (androgen receptor and interleukin 6); and to 3 and 4 weeks (interferon alpha and interferon regulatory factor 7). Others were unique to the various ages, e.g. myelocytomatosis oncogene, jun oncogene, and amyloid beta (A4) to 2 weeks; tumor necrosis factor, transforming growth factor, beta 1, NF?B, ERK, and p38MAPK to 3 weeks; and interleukin 12 and signal transducer and activator of transcription 4 to 4 weeks. Thus, our study demonstrated that expression of many genes that lie within several Idds (e.g. Idd27, Idd13 and Idd9/11) was altered in CD4 T-cells in the early induction phase of autoimmune diabetes and identified their associated molecular pathways. These data offer the opportunity to test hypotheses on the roles played by the altered genes/molecular pathways, to understand better the mechanisms of CD4 T-cell diabetogenesis, and to develop new therapeutic strategies for T1D. PMID:24918037

  14. Poor lysosomal membrane integrity in proximal tubule cells of haptoglobin 2-2 genotype mice with diabetes mellitus

    PubMed Central

    Asleh, Rabea; Nakhoul, Farid M.; Miller-Lotan, Rachel; Awad, Hoda; Farbstein, Dan; Levy, Nina S.; Nakhoul, Nakhoul; Iancu, Theodore C.; Manov, Irena; Laue, Michael; Traber, Maret G.; Lebold, Katie M.; Levy, Andrew P.

    2013-01-01

    The haptoglobin (Hp) genotype is a major determinant of progression of nephropathy in individuals with diabetes mellitus (DM). The major function of the Hp protein is to bind and modulate the fate of extracorpuscular hemoglobin and its iron cargo. We have previously demonstrated an interaction between the Hp genotype and the DM on the accumulation of iron in renal proximal tubule cells. The primary objective of this study was to determine the intracellular localization of this iron in the proximal tubule cell and to assess its potential toxicity. Transmission electron microscopy demonstrated a marked accumulation of electron-dense deposits in the lysosomes of proximal tubules cells in Hp 2-2 DM mice. Energy-dispersive X-ray spectroscopy and electron energy loss spectroscopy were used to perform elemental analysis of these deposits and demonstrated that these deposits were iron rich. These deposits were associated with lysosomal membrane lipid peroxidation and loss of lysosomal membrane integrity. Vitamin E administration to Hp 2-2 DM mice resulted in a significant decrease in both intralysosomal iron-induced oxidation and lysosomal destabilization. Iron-induced renal tubular injury may play a major role in the development of diabetic nephropathy and may be a target for slowing the progression of renal disease. PMID:22749805

  15. Dietary wolfberry ameliorates retinal structure abnormalities in db/db mice at the early stage of diabetes.

    PubMed

    Tang, Ling; Zhang, Yunong; Jiang, Yu; Willard, Lloyd; Ortiz, Edlin; Wark, Logan; Medeiros, Denis; Lin, Dingbo

    2011-09-01

    Hyperglycemia-linked oxidative stress and/or consequent endoplasmic reticulum (ER) stress are the causative factors of pathogenesis of diabetic retinopathy. Dietary bioactive components which mitigate oxidative stress may serve as potential chemopreventive agents to prevent or slow down the disease progression. Wolfberry is a traditional Asian fruit consumed for years to prevent aging eye diseases in Asian countries. Here we report that dietary wolfberry ameliorated mouse retinal abnormality at the early stage of type 2 diabetes in db/db mice. Male mice at six weeks of age were fed the control diet with or without 1% (kcal) wolfberry for eight weeks. Dietary wolfberry restored the thickness of the whole retina, in particular the inner nuclear layer and photoreceptor layer, and the integrity of the retinal pigment epithelia (RPE), and the ganglion cell number in db/db mice. Western blotting of whole retinal cell lysates revealed that addition of wolfberry lowered expression of ER stress biomarkers binding immunoglobulin protein (BiP), protein kinase RNA-like ER kinase (PERK), activating transcription factor 6 (ATF6) and caspase-12, and restored AMP-activated protein kinase (AMPK), thioredoxin, Mn superoxide dismutase (Mn SOD) and forkhead O transcription factor 3 ? (FOXO3?) activities. To determine if our observations were due to the high contents of zeaxanthin and lutein in wolfberry, additional studies using these carotenoids were conducted. Using the human adult diploid RPE cell line ARPE-19, we demonstrated that both zeaxanthin and lutein could mimic the wolfberry preventive effect on activation of AMPK, thioredoxin, Mn SOD, FOXO3? activities, normalize cellular reactive oxygen species and attenuate ER stress in ARPE-19 cells exposed to a high glucose challenge. The zeaxanthin preventive effect was abolished by small interfering RNA knockdown of AMPK?. These results suggested that AMPK activation appeared to play a key role in upregulated expression of thioredoxin and Mn SOD, and mitigation of cellular oxidative stress and/or ER stress by wolfberry and zeaxanthin and/or lutein. Taken together, dietary wolfberry on retinal protection in diabetic mice is, at least partially, due to zeaxanthin and/or lutein. PMID:21750018

  16. Catenarin Prevents Type 1 Diabetes in Nonobese Diabetic Mice via Inhibition of Leukocyte Migration Involving the MEK6/p38 and MEK7/JNK Pathways

    PubMed Central

    Shen, Ming-Yi; Lin, Yu-Ping; Yang, Bei-Chang; Jang, Yu-Song; Chiang, Chih-Kang; Mettling, Clément; Chen, Zeng-Weng; Sheu, Joen-Rong; Chang, Cicero L.; Lin, Yea-Lih; Yang, Wen-Chin

    2012-01-01

    Inflammation contributes to leukocyte migration, termed insulitis, and ?-cell loss in type 1 diabetes (T1D). Naturally occurring anthraquinones are claimed as anti-inflammatory compounds; however, their actions are not clear. This study aimed to investigate the effect and mechanism of catenarin on the inflammatory disease, T1D. Catenarin and/or its anthraquinone analogs dose-dependently suppressed C-X-C chemokine receptor type 4 (CXCR4)- and C-C chemokine receptor type 5 (CCR5)-implicated chemotaxis in leukocytes. Catenarin, the most potent anthraquinone tested in the study, prevented T1D in nonobese diabetic mice. Mechanistic study showed that catenarin did not act on the expression of CCR5 and CXCR4. On the contrary, catenarin inhibited CCR5- and CXCR4-mediated chemotaxis via the reduction of the phosphorylation of mitogen-activated protein kinases (p38 and JNK) and their upstream kinases (MKK6 and MKK7), and calcium mobilization. Overall, the data demonstrate the preventive effect and molecular mechanism of action of catenarin on T1D, suggesting its novel use as a prophylactic agent in T1D. PMID:22454693

  17. Hypoglycemic effect of triterpenoid-rich extracts from Euryale ferox shell on normal and streptozotocin-diabetic mice.

    PubMed

    Yuan, Huaibo; Meng, Shaohua; Wang, Guoze; Gong, Zhaobin; Sun, Wenkai; He, Guoqing

    2014-07-01

    The antioxidant effects of the triterpenoid-rich extracts from Euryale ferox shell (ES) have been confirmed in vitro. This study examined whether the triterpenoid-rich extract from ES eases human hyperglycemia and diabetes caused by metabolic disorders. Normal and streptozocin (STZ)-induced diabetic mice were used as controls for the four groups that received the triterpenoid-rich extracts of ES suspended in distilled water orally at doses of 200, 300, 400, 500±2 mg/L. Body weight, blood glucose and pancreatic tissue morphology were observed after 4 weeks. The expression of protein tyrosine phosphatase-1B (PTP1B) and insulin receptor substrate (IRS-1) proteins, which are related to the regulation of glucose metabolism in vivo, were also investigated. Compared with the model group (LD50 900±2 mg/L), it was found that the triterpenoid-rich extracts of ES could regulate glucose metabolism (P<0.01) and cause body weight to return to normal levels (P<0.05). Islet morphology recovered well, the expression of the negative regulation protein PTP1B gene was reduced and insulin receptor IRS-1 protein expression was increased. These data prove that the triterpenoid-rich extracts from ES have a therapeutic effect on diabetes by insulin resistance. PMID:25015452

  18. Different localization and expression of protein kinase C-beta in kidney cortex of diabetic nephropathy mice and its role in telmisartan treatment

    PubMed Central

    Wang, Jianqing; Qin, Fu; Deng, Anguo; Yao, Lijun

    2015-01-01

    Aim: This study aims to investigate the localization and expression of protein kinase C-beta I and beta II in kidney cortex of diabetic nephropathy mice and their roles in telmisartan treatment. Methods: 18 mice were randomly divided into three groups: normal group, diabetic nephropathy group and telmisartan-treated group. The localization and expression of protein kinase C-beta I and beta II were measured with confocal immunofluorescence laser scanning microscopy, immunohistochemistry and western blotting. The expression of transforming growth factor-beta 1 and vascular endothelial growth factor in glomeruli was detected by immunohistochemistry. Results: Compared to the normal mice, the expression and localization of protein kinase C-beta I and beta II are differed in diabetic nephropathy mice, with increased expression of protein kinase C-beta I but decreased level of protein kinase C-beta II. Meanwhile, the expression of transforming growth factor-beta 1 and vascular endothelial growth factor showed increase in the glomeruli of diabetic nephropathy, compared to the controls. Also, protein kinase C-beta I exhibited a positive correlation to transforming growth factor-beta 1 (r = 0.649, P = 0.030), but no correlation to vascular endothelial growth factor (r = 0.387, P = 0.079). Telmisartan treatment exercised significant beneficial role in diabetic nephropathy, which is associated with protein kinase C-beta I, but not beta II. Conclusions: The expression and localization of protein kinase C-beta I and beta II differ in the diabetic nephropathy, and such difference is associated with the pathogeneses of diabetic nephropathy. PMID:26279755

  19. Far infra-red therapy promotes ischemia-induced angiogenesis in diabetic mice and restores high glucose-suppressed endothelial progenitor cell functions

    PubMed Central

    2012-01-01

    Background Far infra-red (IFR) therapy was shown to exert beneficial effects in cardiovascular system, but effects of IFR on endothelial progenitor cell (EPC) and EPC-related vasculogenesis remain unclear. We hypothesized that IFR radiation can restore blood flow recovery in ischemic hindlimb in diabetic mice by enhancement of EPCs functions and homing process. Materials and methods Starting at 4 weeks after the onset of diabetes, unilateral hindlimb ischemia was induced in streptozotocine (STZ)-induced diabetic mice, which were divided into control and IFR therapy groups (n?=?6 per group). The latter mice were placed in an IFR dry sauna at 34°C for 30 min once per day for 5 weeks. Results Doppler perfusion imaging demonstrated that the ischemic limb/normal side blood perfusion ratio in the thermal therapy group was significantly increased beyond that in controls, and significantly greater capillary density was seen in the IFR therapy group. Flow cytometry analysis showed impaired EPCs (Sca-1+/Flk-1+) mobilization after ischemia surgery in diabetic mice with or without IFR therapy (n?=?6 per group). However, as compared to those in the control group, bone marrow-derived EPCs differentiated into endothelial cells defined as GFP+/CD31+ double-positive cells were significantly increased in ischemic tissue around the vessels in diabetic mice that received IFR radiation. In in-vitro studies, cultured EPCs treated with IFR radiation markedly augmented high glucose-impaired EPC functions, inhibited high glucose-induced EPC senescence and reduced H2O2 production. Nude mice received human EPCs treated with IFR in high glucose medium showed a significant improvement in blood flow recovery in ischemic limb compared to those without IFR therapy. IFR therapy promoted blood flow recovery and new vessel formation in STZ-induced diabetic mice. Conclusions Administration of IFR therapy promoted collateral flow recovery and new vessel formation in STZ-induced diabetic mice, and these beneficial effects may derive from enhancement of EPC functions and homing process. PMID:22894755

  20. Angioblast Derived from ES Cells Construct Blood Vessels and Ameliorate Diabetic Polyneuropathy in Mice

    PubMed Central

    Kamiya, Hideki; Naruse, Keiko; Cheng, Zhao; Ito, Sachiko; Shibata, Taiga; Kondo, Masaki; Kato, Jiro; Okawa, Tetsuji; Fujiya, Atsushi; Suzuki, Hirohiko; Kito, Tetsutaro; Hamada, Yoji; Oiso, Yutaka; Isobe, Kenichi; Nakamura, Jiro

    2015-01-01

    Background. Although numerous reports addressing pathological involvements of diabetic polyneuropathy have been conducted, a universally effective treatment of diabetic polyneuropathy has not yet been established. Recently, regenerative medicine studies in diabetic polyneuropathy using somatic stem/progenitor cell have been reported. However, the effectiveness of these cell transplantations was restricted because of their functional and numerical impairment in diabetic objects. Here, we investigated the efficacy of treatment for diabetic polyneuropathy using angioblast-like cells derived from mouse embryonic stem cells. Methods and Results. Angioblast-like cells were obtained from mouse embryonic stem cells and transplantation of these cells improved several physiological impairments in diabetic polyneuropathy: hypoalgesia, delayed nerve conduction velocities, and reduced blood flow in sciatic nerve and plantar skin. Furthermore, pathologically, the capillary number to muscle fiber ratios were increased in skeletal muscles of transplanted hindlimbs, and intraepidermal nerve fiber densities were ameliorated in transplanted plantar skin. Transplanted cells maintained their viabilities and differentiated to endothelial cells and smooth muscle cells around the injection sites. Moreover, several transplanted cells constructed chimeric blood vessels with recipient cells. Conclusions. These results suggest that transplantation of angioblast like cells induced from embryonic stem cells appears to be a novel therapeutic strategy for diabetic polyneuropathy. PMID:25977928

  1. Ameliorative Effect of Hexane Extract of Phalaris canariensis on High Fat Diet-Induced Obese and Streptozotocin-Induced Diabetic Mice

    PubMed Central

    Perez Gutierrez, Rosa Martha; Madrigales Ahuatzi, Diana; Horcacitas, Maria del Carmen; Garcia Baez, Efren; Cruz Victoria, Teresa; Mota-Flores, Jose Maria

    2014-01-01

    Obesity is one of the major factors to increase various disorders like diabetes. The present paper emphasizes study related to the antiobesity effect of Phalaris canariensis seeds hexane extract (Al-H) in high-fat diet- (HFD-) induced obese CD1 mice and in streptozotocin-induced mild diabetic (MD) and severely diabetic (SD) mice.AL-H was orally administered to MD and SD mice at a dose of 400?mg/kg once a day for 30 days, and a set of biochemical parameters were studied: glucose, cholesterol, triglycerides, lipid peroxidation, liver and muscle glycogen, ALP, SGOT, SGPT, glucose-6-phosphatase, glucokinase, hexokinase, SOD, CAT, GSH, GPX activities, and the effect on insulin level. HS-H significantly reduced the intake of food and water and body weight loss as well as levels of blood glucose, serum cholesterol, triglyceride, lipoprotein, oxidative stress, showed a protective hepatic effect, and increased HDL-cholesterol, serum insulin in diabetic mice. The mice fed on the high-fat diet and treated with AL-H showed inhibitory activity on the lipid metabolism decreasing body weight and weight of the liver and visceral adipose tissues and cholesterol and triglycerides in the liver. We conclude that AL-H can efficiently reduce serum glucose and inhibit insulin resistance, lipid abnormalities, and oxidative stress in MD and SD mice. Our results demonstrate an antiobesity effect reducing lipid droplet accumulation in the liver, indicating that its therapeutic properties may be due to the interaction plant components soluble in the hexane extract, with any of the multiple targets involved in obesity and diabetes pathogenesis. PMID:24523819

  2. Molecular hydrogen improves obesity and diabetes by inducing hepatic FGF21 and stimulating energy metabolism in db/db mice.

    PubMed

    Kamimura, Naomi; Nishimaki, Kiyomi; Ohsawa, Ikuroh; Ohta, Shigeo

    2011-07-01

    Recent extensive studies have revealed that molecular hydrogen (H(2)) has great potential for improving oxidative stress-related diseases by inhaling H(2) gas, injecting saline with dissolved H(2), or drinking water with dissolved H(2) (H(2)-water); however, little is known about the dynamic movement of H(2) in a body. First, we show that hepatic glycogen accumulates H(2) after oral administration of H(2)-water, explaining why consumption of even a small amount of H(2) over a short span time efficiently improves various disease models. This finding was supported by an in vitro experiment in which glycogen solution maintained H(2). Next, we examined the benefit of ad libitum drinking H(2)-water to type 2 diabetes using db/db obesity model mice lacking the functional leptin receptor. Drinking H(2)-water reduced hepatic oxidative stress, and significantly alleviated fatty liver in db/db mice as well as high fat-diet-induced fatty liver in wild-type mice. Long-term drinking H(2)-water significantly controlled fat and body weights, despite no increase in consumption of diet and water. Moreover, drinking H(2)-water decreased levels of plasma glucose, insulin, and triglyceride, the effect of which on hyperglycemia was similar to diet restriction. To examine how drinking H(2)-water improves obesity and metabolic parameters at the molecular level, we examined gene-expression profiles, and found enhanced expression of a hepatic hormone, fibroblast growth factor 21 (FGF21), which functions to enhance fatty acid and glucose expenditure. Indeed, H(2) stimulated energy metabolism as measured by oxygen consumption. The present results suggest the potential benefit of H(2) in improving obesity, diabetes, and metabolic syndrome. PMID:21293445

  3. Reversal of Muscle Atrophy by Zhimu-Huangbai Herb-Pair via Akt/mTOR/FoxO3 Signal Pathway in Streptozotocin-Induced Diabetic Mice

    PubMed Central

    Wang, Yan; Song, Lili; Zhang, Mixia; Lu, Zhiqiang; Zhang, Lu; Wang, Jing; Alemu, Paulos N.; Zhang, Yanjun; Wei, Hongjun; Li, Hongyan

    2014-01-01

    Skeletal muscle atrophy is one of the serious complications of diabetes. Zhimu-Huangbai herb-pair (ZB) is widely used in Chinese traditional medicine formulas for treating Xiaoke (known as diabetes) and its complications. However, the effect of ZB on reversal of muscle atrophy and the underlying mechanisms remain unknown. In this research, we investigated the effect and possible mechanisms of ZB on skeletal muscle atrophy in diabetic mice. Animal model of diabetic muscle atrophy was developed by high fat diet (HFD) feeding plus streptozotocin (STZ) injection. After oral adminstration of ZB for 6 weeks, the effects of ZB on reversal of muscle atrophy and the underlying mechanisms were evaluated by biochemical, histological and western blot methods. The skeletal muscle weight, strength, and cross-sectional area of diabetic mice were significantly increased by ZB treatment. Biochemical results showed that ZB treatment reduced the serum glucose level, and elevated the serum insulin-like growth factor 1 (IGF-1) and insulin levels significantly compared with untreated diabetic group. The western blot results showed that ZB activated the mTOR signal pathway, shown as increased phosphorylations (p-) of Akt, mTOR, Raptor, S6K1 and reduced Foxo3 expression compared with the model group. ZB could reverse muscle atrophy in diabetic mice. This may be through activation of mTOR signaling pathway that promotes protein synthesis, and inactivation foxo3 protein that inhibits protein degradation. These findings suggested that ZB may be considered as a potential candidate drug in treatment of diabetic muscle atrophy. PMID:24968071

  4. Deficit of tRNALys modification by Cdkal1 causes the development of type 2 diabetes in mice

    PubMed Central

    Wei, Fan-Yan; Suzuki, Takeo; Watanabe, Sayaka; Kimura, Satoshi; Kaitsuka, Taku; Fujimura, Atsushi; Matsui, Hideki; Atta, Mohamed; Michiue, Hiroyuki; Fontecave, Marc; Yamagata, Kazuya; Suzuki, Tsutomu; Tomizawa, Kazuhito

    2011-01-01

    The worldwide prevalence of type 2 diabetes (T2D), which is caused by a combination of environmental and genetic factors, is increasing. With regard to genetic factors, variations in the gene encoding Cdk5 regulatory associated protein 1–like 1 (Cdkal1) have been associated with an impaired insulin response and increased risk of T2D across different ethnic populations, but the molecular function of this protein has not been characterized. Here, we show that Cdkal1 is a mammalian methylthiotransferase that biosynthesizes 2-methylthio-N6-threonylcarbamoyladenosine (ms2t6A) in tRNALys(UUU) and that it is required for the accurate translation of AAA and AAG codons. Mice with pancreatic ? cell–specific KO of Cdkal1 (referred to herein as ? cell KO mice) showed pancreatic islet hypertrophy, a decrease in insulin secretion, and impaired blood glucose control. In Cdkal1-deficient ? cells, misreading of Lys codon in proinsulin occurred, resulting in a reduction of glucose-stimulated proinsulin synthesis. Moreover, expression of ER stress–related genes was upregulated in these cells, and abnormally structured ER was observed. Further, the ? cell KO mice were hypersensitive to high fat diet–induced ER stress. These findings suggest that glucose-stimulated translation of proinsulin may require fully modified tRNALys(UUU), which could potentially explain the molecular pathogenesis of T2D in patients carrying cdkal1 risk alleles. PMID:21841312

  5. CHARACTERIZATION & TREATMENT OF LARGE SENSORY FIBER PERIPHERAL NEUROPATHY IN DIABETIC MICE

    E-print Network

    Muller, Karra

    2008-11-17

    Patients with large-fiber diabetic sensorimotor polyneuropathy (DPN) can develop altered sensorimotor function. Gait and balance control are regulated, in part, through large sensory nerves innervating muscle spindles. The overall goal...

  6. Inhibiting heat-shock protein 90 reverses sensory hypoalgesia in diabetic mice

    E-print Network

    Urban, Michael Joseph; Li, Chengyuan; Yu, Cuijuan; Lu, Yuanming; Krise, Joanna M.; McIntosh, Michelle P.; Rajewski, Roger A.; Blagg, Brian S. J.; Dobrowsky, Rick T.

    2010-07-14

    Increasing the expression of Hsp70 (heat-shock protein 70) can inhibit sensory neuron degeneration after axotomy. Since the onset of DPN (diabetic peripheral neuropathy) is associated with the gradual decline of sensory neuron function, we evaluated...

  7. Amelioration of Hyperglycemia with a Sodium-Glucose Cotransporter 2 Inhibitor Prevents Macrophage-Driven Atherosclerosis through Macrophage Foam Cell Formation Suppression in Type 1 and Type 2 Diabetic Mice

    PubMed Central

    Terasaki, Michishige; Hiromura, Munenori; Mori, Yusaku; Kohashi, Kyoko; Nagashima, Masaharu; Kushima, Hideki; Watanabe, Takuya; Hirano, Tsutomu

    2015-01-01

    Direct associations between hyperglycemia and atherosclerosis remain unclear. We investigated the association between the amelioration of glycemia by sodium-glucose cotransporter 2 inhibitors (SGLT2is) and macrophage-driven atherosclerosis in diabetic mice. We administered dapagliflozin or ipragliflozin (1.0 mg/kg/day) for 4-weeks to apolipoprotein E-null (Apoe?/?) mice, streptozotocin-induced diabetic Apoe?/? mice, and diabetic db/db mice. We then determined aortic atherosclerosis, oxidized low-density lipoprotein (LDL)-induced foam cell formation, and related gene expression in exudate peritoneal macrophages. Dapagliflozin substantially decreased glycated hemoglobin (HbA1c) and glucose tolerance without affecting body weight, blood pressure, plasma insulin, and lipids in diabetic Apoe?/? mice. Aortic atherosclerotic lesions, atheromatous plaque size, and macrophage infiltration in the aortic root increased in diabetic Apoe?/? mice; dapagliflozin attenuated these changes by 33%, 27%, and 20%, respectively. Atherosclerotic lesions or foam cell formation highly correlated with HbA1c. Dapagliflozin did not affect atherosclerosis or plasma parameters in non-diabetic Apoe?/? mice. In db/db mice, foam cell formation increased by 4-fold compared with C57/BL6 mice, whereas ipragliflozin decreased it by 31%. Foam cell formation exhibited a strong correlation with HbA1c. Gene expression of lectin-like ox-LDL receptor-1 and acyl-coenzyme A:cholesterol acyltransferase 1 was upregulated, whereas that of ATP-binding cassette transporter A1 was downregulated in the peritoneal macrophages of both types of diabetic mice. SGLT2i normalized these gene expressions. Our study is the first to demonstrate that SGLT2i exerts anti-atherogenic effects by pure glucose lowering independent of insulin action in diabetic mice through suppressing macrophage foam cell formation, suggesting that foam cell formation is highly sensitive to glycemia ex vivo. PMID:26606676

  8. Supplementary Effects of Lentinus edodes with Different Harvest Period and Part on Neurotransmitters and Lipid peroxide levels in the Brain of Diabetic Mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was designed to investigate the supplementary effects of Lentinus edodes which were harvested at different time period and part on acetylcholine content and its related enzyme activities in the brain of diabetic mouse model (KK mouse). We fed mice with standard diet(Control diet; CON) and...

  9. Effect of antioxidant extract from cherries on diabetes.

    PubMed

    Lachin, Tahsini

    2014-01-01

    Diabetes is a chronic metabolic disorder in humans constituting a major health concern today whose prevalence has continuously increased worldwide over the past few decades. Production of reactive oxygen species (ROS) and disturbed capacity of antioxidant defense in diabetic subjects have been reported. It has been suggested that enhanced production of free radicals and oxidative stress is the central event for the development of diabetic complications. Antioxidants can play an important role in the improvement of diabetes. There are many reports on the effects of antioxidants in the management of diabetes. This study aimed at evaluating the effect of antioxidant extract and purified sweet and sour Cherries on hyperglycemia, microalbumin and creatinine level in alloxan-induced diabetic rats. Thirty six adult Male Wistar rats were divided equally into six groups. Diabetes was induced in the rats by an intraperitoneal injection with 120 mg/kg body weight of alloxan. Oral administration of cherry extract at a concentration of 200 mg/kg body weight for 30 days significantly reduced the levels of blood glucose, and urinary microalbumin. Also an increase in the creatinine secretion level in urine was observed in the diabetic rats treated with the cherry extract as compared to untreated diabetic rats. In this paper, the most recent patent on the identification and treatment of diabetes is used. In conclusion, cherry antioxidant extract proved to have a beneficial effect on the diabetic rats in this study. In light of these advantageous results, it is advisable to broaden the scale of use of sweet and sour cherries extract in a trial to alleviate the adverse effects of diabetes. PMID:24447011

  10. Phenotypic Characterization of Mice Carrying Homozygous Deletion of KLF11, a Gene in Which Mutations Cause Human Neonatal and MODY VII Diabetes

    PubMed Central

    Mathison, Angela; Escande, Carlos; Calvo, Ezequiel; Seo, Seungmae; White, Thomas; Salmonson, Ann; Faubion, William A.; Buttar, Navtej; Iovanna, Juan; Lomberk, Gwen; Chini, Eduardo N.

    2015-01-01

    We have previously shown that amino acid changes in the human Kruppel-Like Factor (KLF) 11 protein is associated with the development of maturity onset diabetes of the young VII, whereas complete inactivation of this pathway by the ?331 human insulin mutation causes neonatal diabetes mellitus. Here, we report that Klf11?/? mice have decreased circulating insulin levels, alterations in the control of blood glucose and body weight, as well as serum dyslipidemia, but do not develop diabetes. Functional assays using ex vivo liver tissue sections demonstrate that Klf11?/? mice display increased insulin sensitivity. Genome-wide experiments validated by pathway-specific quantitative PCR arrays reveal that the Klf11?/? phenotype associates to alterations in the regulation of gene networks involved in lipid metabolism, in particular those regulated by peroxisome proliferator-activated receptor-?. Combined, these results demonstrate that the major phenotype given by the whole-body deletion of Klf11 in mouse is not diabetes but increased insulin sensitivity, likely due to altered transcriptional regulation in target tissues. The absence of diabetes in the Klf11?/? mouse either indicates an interspecies difference for the role of this transcription factor in metabolic homeostasis between mouse and humans, or potentially highlights the fact that other molecular factors can compensate for its absence. Nevertheless, the data of this study, gathered at the whole-organism level, further support a role for KLF11 in metabolic processes like insulin sensitivity, which regulation is critical in several forms of diabetes. PMID:26248217

  11. Alteration of Mevalonate Pathway in Proliferated Vascular Smooth Muscle from Diabetic Mice: Possible Role in High-Glucose-Induced Atherogenic Process

    PubMed Central

    Zhang, Xiao-Qin; Wu, Tao; Li, Liang; Han, Jie; Du, Chang-Qing

    2015-01-01

    The proliferation of vascular smooth muscle cells (VSMCs) is one of the main features of atherosclerosis induced by high glucose. Mevalonate pathway is an important metabolic pathway that plays a key role in multiple cellular processes. The aim of this study was to define whether the enzyme expression in mevalonate pathway is changed in proliferated VSMCs during atherogenic process in diabetic mice. Diabetes was induced in BALB/c mice with streptozotocin (STZ, 50?mg/kg/day for 5 days). Induction of diabetes with STZ was associated with an increase of lesion area and media thickness after 8 and 16 weeks of diabetes. In aorta, there were overexpressions of some enzymes, including 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGR), farnesyl pyrophosphate synthase (FPPS), geranylgeranyl pyrophosphate synthase (GGPPS), farnesyltransferase (FNT), and geranylgeranyltransferase-1 (GGT-1), and unchanged expression of squalene synthase (SQS) and phosphor-3-hydroxy-3-methylglutaryl-coenzyme A reductase (P-HMGR) in 8 and 16 weeks of diabetes. In vitro, VSMCs were cultured and treated with different glucose concentrations for 48?h. High glucose (22.2?mM) induced VSMC proliferation and upregulation of HMGR, FPPS, GGPPS, FNT, and GGT-1 but did not change the expressions of SQS and P-HMGR. In conclusion, altered expression of several key enzymes in the mevalonate pathway may play a potential pathophysiological role in atherogenic process of diabetes macrovascular complication. PMID:25918730

  12. Phenotypic Characterization of Mice Carrying Homozygous Deletion of KLF11, a Gene in Which Mutations Cause Human Neonatal and MODY VII Diabetes.

    PubMed

    Mathison, Angela; Escande, Carlos; Calvo, Ezequiel; Seo, Seungmae; White, Thomas; Salmonson, Ann; Faubion, William A; Buttar, Navtej; Iovanna, Juan; Lomberk, Gwen; Chini, Eduardo N; Urrutia, Raul

    2015-10-01

    We have previously shown that amino acid changes in the human Kruppel-Like Factor (KLF) 11 protein is associated with the development of maturity onset diabetes of the young VII, whereas complete inactivation of this pathway by the -331 human insulin mutation causes neonatal diabetes mellitus. Here, we report that Klf11-/- mice have decreased circulating insulin levels, alterations in the control of blood glucose and body weight, as well as serum dyslipidemia, but do not develop diabetes. Functional assays using ex vivo liver tissue sections demonstrate that Klf11-/- mice display increased insulin sensitivity. Genome-wide experiments validated by pathway-specific quantitative PCR arrays reveal that the Klf11-/- phenotype associates to alterations in the regulation of gene networks involved in lipid metabolism, in particular those regulated by peroxisome proliferator-activated receptor-?. Combined, these results demonstrate that the major phenotype given by the whole-body deletion of Klf11 in mouse is not diabetes but increased insulin sensitivity, likely due to altered transcriptional regulation in target tissues. The absence of diabetes in the Klf11-/- mouse either indicates an interspecies difference for the role of this transcription factor in metabolic homeostasis between mouse and humans, or potentially highlights the fact that other molecular factors can compensate for its absence. Nevertheless, the data of this study, gathered at the whole-organism level, further support a role for KLF11 in metabolic processes like insulin sensitivity, which regulation is critical in several forms of diabetes. PMID:26248217

  13. Lack of both bradykinin B1 and B2 receptors enhances nephropathy, neuropathy, and bone mineral loss in Akita diabetic mice

    PubMed Central

    Kakoki, Masao; Sullivan, Kelli A.; Backus, Carey; Hayes, John M.; Oh, Sang Su; Hua, Kunjie; Gasim, Adil M. H.; Tomita, Hirofumi; Grant, Ruriko; Nossov, Sarah B.; Kim, Hyung-Suk; Jennette, J. Charles; Feldman, Eva L.; Smithies, Oliver

    2010-01-01

    An insertion polymorphism of the angiotensin-I converting enzyme gene (ACE) is common in humans and the higher expressing allele is associated with an increased risk of diabetic complications. The ACE polymorphism does not significantly affect blood pressure or angiotensin II levels, suggesting that the kallikrein-kinin system partly mediates the effects of the polymorphism. We have therefore explored the influence of lack of both bradykinin receptors (B1R and B2R) on diabetic nephropathy, neuropathy, and osteopathy in male mice heterozygous for the Akita diabetogenic mutation in the insulin 2 gene (Ins2). We find that all of the detrimental phenotypes observed in Akita diabetes are enhanced by lack of both B1R and B2R, including urinary albumin excretion, glomerulosclerosis, glomerular basement membrane thickening, mitochondrial DNA deletions, reduction of nerve conduction velocities and of heat sensation, and bone mineral loss. Absence of the bradykinin receptors also enhances the diabetes-associated increases in plasma thiobarbituric acid-reactive substances, mitochondrial DNA deletions, and renal expression of fibrogenic genes, including transforming growth factor beta1, connective tissue growth factor, and endothelin-1. Thus, lack of B1R and B2R exacerbates diabetic complications. The enhanced renal injury in diabetic mice caused by lack of B1R and B2R may be mediated by a combination of increases in oxidative stress, mitochondrial DNA damage and over expression of fibrogenic genes. PMID:20479236

  14. Mitochondrial DNA polymerase editing mutation, PolgD257A, reduces the diabetic phenotype of Akita male mice by suppressing appetite

    PubMed Central

    Fox, Raymond; Kim, Hyung-Suk; Reddick, Robert L.; Kujoth, Gregory C.; Prolla, Tomas A.; Tsutsumi, Shuichi; Wada, Youichiro; Smithies, Oliver; Maeda, Nobuyo

    2011-01-01

    Diabetes and the development of its complications have been associated with mitochondrial DNA (mtDNA) dysfunction, but causal relationships remain undetermined. With the objective of testing whether increased mtDNA mutations exacerbate the diabetic phenotype, we have compared mice heterozygous for the Akita diabetogenic mutation (Akita) with mice homozygous for the D257A mutation in mitochondrial DNA polymerase gamma (Polg) or with mice having both mutations (Polg-Akita). The Polg-D257A protein is defective in proofreading and increases mtDNA mutations. At 3 mo of age, the Polg-Akita and Akita male mice were equally hyperglycemic. Unexpectedly, as the Polg-Akita males aged to 9 mo, their diabetic symptoms decreased. Thus, their hyperglycemia, hyperphagia and urine output declined significantly. The decrease in their food intake was accompanied by increased plasma leptin and decreased plasma ghrelin, while hypothalamic expression of the orexic gene, neuropeptide Y, was lower and expression of the anorexic gene, proopiomelanocortin, was higher. Testis function progressively worsened with age in the double mutants, and plasma testosterone levels in 9-mo-old Polg-Akita males were significantly reduced compared with Akita males. The hyperglycemia and hyperphagia returned in aged Polg-Akita males after testosterone administration. Hyperglycemia-associated distal tubular damage in the kidney also returned, and Polg-D257A-associated proximal tubular damage was enhanced. The mild diabetes of female Akita mice was not affected by the Polg-D257A mutation. We conclude that reduced diabetic symptoms of aging Polg-Akita males results from appetite suppression triggered by decreased testosterone associated with damage to the Leydig cells of the testis. PMID:21555558

  15. Beneficial Effect of 7-O-Galloyl-D-sedoheptulose, a Polyphenol Isolated from Corni Fructus, against Diabetes-Induced Alterations in Kidney and Adipose Tissue of Type 2 Diabetic db/db Mice

    PubMed Central

    Park, Chan Hum; Noh, Jeong Sook; Park, Jong Cheol; Yokozawa, Takako

    2013-01-01

    Traditional medicines are being focused on as possible treatments for diabetes and its complications because of their negligible toxic and/or side effects. In line with this, our group has reported that Corni Fructus, a traditional medicine considered exhibiting beneficial effects on liver and kidney functions, possessed an antidiabetic effect via ameliorating glucose-mediated metabolic disorders. To add to these findings, we screened the iridoid glycoside fraction containing morroniside and loganin, and low molecular weight polyphenol fraction containing 7-O-galloyl-d-sedoheptulose (GS) from Corni Fructus. To our knowledge, GS is a compound only detected in Corni Fructus, and its biological activity has been poorly understood until now. For these reasons, we examined whether GS has an ameliorative effect on diabetic changes using type 2 diabetic db/db mice. Our findings suggest that GS has a beneficial effect on the pathological state of the serum, kidney, and adipose tissue related to diabetic damage. PMID:24348717

  16. Negative Regulation of Grb10 Interacting GYF Protein 2 on Insulin-Like Growth Factor-1 Receptor Signaling Pathway Caused Diabetic Mice Cognitive Impairment

    PubMed Central

    Xie, Jing; Wei, Qianping; Deng, Huacong; Li, Gang; Ma, Lingli; Zeng, Hui

    2014-01-01

    Heterozygous Gigyf2+/? mice exhibits histopathological evidence of neurodegeneration such as motor dysfunction. Several lines of evidence have demonstrated the important role of insulin-like growth factor-1 receptor (IGF1R) signaling pathway in the neuropathogenic process of cognitive impairment, while decreased Grb10-Interacting GYF Protein 2 (GIGYF2) expression can alter IGF1R trafficking and its downstream signaling pathways. Growth factor receptor-bound protein 10 (Grb10), a suppressor of IGF1R pathway, has been shown to play a critical role in regulating diabetes-associated cognitive impairment. It remains unknown whether endogenous GIGYF2 expression contributes to the development of diabetes-associated cognitive impairment. Using streptozotocin (STZ)-induced diabetic mice model, we first demonstrated that a significantly increased level of GIGYF2 expression was correlated with a significant decrease in the expression of phosphorylated IGF1R as well as the phosphorylation of AKT and ERK1/2, two signaling pathways downstream of IGF1R, in the hippocampus of diabetic mice. On the contrary, in situ knockdown of GIGYF2 expression in hippocampus resulted in increased expression of phosphorylated IGF1R expression and correspondingly reversed the down-regulation of ERK1/2 phsophorylation but had no obvious effect on Grb10 expression. Functionally, knockdown of GIGYF2 expression markedly ameliorated diabetes-associated cognitive dysfunction as well as the ultrastructural pathology and abnormal neurobehavioral changes. These results suggest that increased expression of GIGYF2 might contribute to the development of diabetes-associated cognitive disorder via negatively regulating IGF1R signaling pathway. Therefore, down-regulation of GIGYF2 expression may provide a potential novel approach to treat diabetes-associated cognitive impairment caused by aberrant IGF1R signaling pathway. PMID:25268761

  17. Type 1 Diabetes Prevention in NOD Mice by Targeting DPPIV/CD26 Is Associated with Changes in CD8+T Effector Memory Subset

    PubMed Central

    Carrascal, Jorge; Colobran, Roger; Pujol-Autonell, Irma; Rodriguez-Fernández, Silvia; Teniente, Aina; Fernández, Marco Antonio; Miñarro, Antoni; Ruiz de Villa, María Carmen; Vives-Pi, Marta; Puig-Domingo, Manel

    2015-01-01

    CD26 is a T cell activation marker consisting in a type II transmembrane glycoprotein with dipeptidyl peptidase IV (DPPIV) activity in its extracellular domain. It has been described that DPPIV inhibition delays the onset of type 1 diabetes and reverses the disease in non-obese diabetic (NOD) mice. The aim of the present study was to assess the effect of MK626, a DPPIV inhibitor, in type 1 diabetes incidence and in T lymphocyte subsets at central and peripheral compartments. Pre-diabetic NOD mice were treated with MK626. Diabetes incidence, insulitis score, and phenotyping of T lymphocytes in the thymus, spleen and pancreatic lymph nodes were determined after 4 and 6 weeks of treatment, as well as alterations in the expression of genes encoding ?-cell autoantigens in the islets. The effect of MK626 was also assessed in two in vitro assays to determine proliferative and immunosuppressive effects. Results show that MK626 treatment reduces type 1 diabetes incidence and after 6 weeks of treatment reduces insulitis. No differences were observed in the percentage of T lymphocyte subsets from central and peripheral compartments between treated and control mice. MK626 increased the expression of CD26 in CD8+ T effector memory (TEM) from spleen and pancreatic lymph nodes and in CD8+ T cells from islet infiltration. CD8+TEM cells showed an increased proliferation rate and cytokine secretion in the presence of MK626. Moreover, the combination of CD8+ TEM cells and MK626 induces an immunosuppressive response. In conclusion, treatment with the DPPIV inhibitor MK626 prevents experimental type 1 diabetes in association to increase expression of CD26 in the CD8+ TEM lymphocyte subset. In vitro assays suggest an immunoregulatory role of CD8+ TEM cells that may be involved in the protection against autoimmunity to ? pancreatic islets associated to DPPIV inhibitor treatment. PMID:26555789

  18. Diabetes mellitus: An overview on its pharmacological aspects and reported medicinal plants having antidiabetic activity

    PubMed Central

    Patel, DK; Kumar, R; Laloo, D; Hemalatha, S

    2012-01-01

    Diabetes mellitus is not a single disease but is a group of metabolic disorders affecting a huge number of population in the world. It is mainly characterized by chronic hyperglycemia, resulting from defects in insulin secretion or insulin action. It is predicated that the number of diabetes person in the world could reach upto 366 million by the year 2030. Even though the cases of diabetes are increasing day by day, except insulin and oral hypoglycemic drugs no other way of treatment has been successfully developed so far. Thus, the objective of the present review is to provide an insight over the pathophysiological and etiological aspects of diabetes mellitus along with the remedies available for this metabolic disorder. The review also contains brief idea about diabetes mellitus and the experimental screening model with their relevant mechanism and significance mainly used nowadays. Alloxan and streptozotocin are mainly used for evaluating the antidiabetic activity of a particular drug. This review contain list of medicinal plants which have been tested for their antidiabetic activity in the alloxan induced diabetic rat model. From the available data in the literature, it was found that plant having antidiabetic activity is mainly due to the presence of the secondary metabolite. Thus, the information provided in this review will help the researchers for the development of an alternative methods rather than insulin and oral hypoglycemic agents for the treatment of diabetes mellitus, which will minimize the complication associated with the diabetes and related disorder. PMID:23569941

  19. Guaifenesin derivatives promote neurite outgrowth and protect diabetic mice from neuropathy.

    PubMed

    Hadimani, Mallinath B; Purohit, Meena K; Vanampally, Chandrashaker; Van der Ploeg, Randy; Arballo, Victor; Morrow, Dwane; Frizzi, Katie E; Calcutt, Nigel A; Fernyhough, Paul; Kotra, Lakshmi P

    2013-06-27

    In diabetic patients, an early index of peripheral neuropathy is the slowing of conduction velocity in large myelinated neurons and a lack of understanding of the basic pathogenic mechanisms hindered therapeutics development. Racemic (R/S)-guaifenesin (1) was identified as a potent enhancer of neurite outgrowth using an in vitro screen. Its R-enantiomer (R)-1 carried the most biological activity, whereas the S-enantiomer (S)-1 was inactive. Focused structural variations to (R/S)-1 was conducted to identify potentially essential groups for the neurite outgrowth activity. In vivo therapeutic studies indicated that both (R/S)-1 and (R)-1 partially prevented motor nerve conduction velocity slowing in a mouse model of type 1 diabetes. In vitro microsomal assays suggested that compounds (R)-1 and (S)-1 are not metabolized rapidly, and PAMPA assay indicated moderate permeability through the membrane. Findings revealed here could lead to the development of novel drugs for diabetic neuropathy. PMID:23758573

  20. Over-expression of Stat5b confers protection against diabetes in the non-obese diabetic (NOD) mice via up-regulation of CD4{sup +}CD25{sup +} regulatory T cells

    SciTech Connect

    Jin, Yulan; Purohit, Sharad; Department of Pathology, Medical College of Georgia, Georgia Health Sciences University, GA ; Chen, Xueqin; Yi, Bing; She, Jin-Xiong; Department of Pathology, Medical College of Georgia, Georgia Health Sciences University, GA

    2012-08-10

    Highlights: Black-Right-Pointing-Pointer This is the first study to provide direct evidence of the role of Stat5b in NOD mice. Black-Right-Pointing-Pointer Over-expression of wild type Stat5b transgene protects NOD mice against diabetes. Black-Right-Pointing-Pointer This protection may be mediated by the up-regulation of CD4{sup +}CD25{sup +} Tregs. -- Abstract: The signal transducers and activators of transcription (STAT) family of proteins play a critical role in cytokine signaling required for fine tuning of immune regulation. Previous reports showed that a mutation (L327M) in the Stat5b protein leads to aberrant cytokine signaling in the NOD mice. To further elaborate the role of Stat5b in diabetes, we established a NOD transgenic mouse that over-expresses the wild type Stat5b gene. The incidences of spontaneous diabetes as well as cyclophosphamide-induced diabetes were significantly reduced and delayed in the Stat5b transgenic NOD mice compared to their littermate controls. The total cell numbers of CD4{sup +} T cells and especially CD8{sup +} T cells in the spleen and pancreatic lymph node were increased in the Stat5b transgenic NOD mice. Consistent with these findings, CD4{sup +} and CD8{sup +} T cells from the Stat5b transgenic NOD mice showed a higher proliferation capacity and up-regulation of multiple cytokines including IL-2, IFN-{gamma}, TNF-{alpha} and IL-10 as well as anti-apoptotic gene Bcl-xl. Furthermore, the number and proportion of CD4{sup +}CD25{sup +} regulatory T cells were significantly increased in transgenic mice although in vitro suppression ability of the regulatory T-cells was not affected by the transgene. Our results suggest that Stat5b confers protection against diabetes in the NOD mice by regulating the numbers and function of multiple immune cell types, especially by up-regulating CD4{sup +}CD25{sup +} regulatory T cells.

  1. Effects of the Combined Extracts of Grape Pomace and Omija Fruit on Hyperglycemia and Adiposity in Type 2 Diabetic Mice

    PubMed Central

    Cho, Su-Jung; Jung, Un Ju; Kim, Hye-Jin; Ryu, Ri; Ryoo, Jae Young; Moon, Byoung Seok; Choi, Myung-Sook

    2015-01-01

    Grape products have been known to exert greater antioxidant and anti-obesity than anti-hyperglycemic effects in animals and humans. Omija is used as an ingredient in traditional medicine, and it is known to have an anti-hyperglycemic effect. We investigated whether the combined extracts of grape pomace and omija fruit (GE+OE) could reduce fat accumulation in adipose and hepatic tissues and provide beneficial effects against hyperglycemia and insulin resistance in type 2 diabetic mice. C57BL/KsJ-db/db mice were fed either a normal control diet or GE+OE (0.5% grape pomace extract and 0.05% omija fruit extract, w/w) for 7 weeks. GE+OE decreased plasma leptin and resistin levels while increasing adiponectin levels and reducing the total white adipose tissue weight. Furthermore, GE+OE lowered plasma free fatty acid (FFA), triglyceride, and total-cholesterol levels as well as hepatic FFA and cholesterol levels. Hepatic fatty acid synthase and glucose 6-phosphate dehydrogenase activities were decreased in the GE+OE group, whereas hepatic ?-oxidation activity was increased. Furthermore, GE+OE supplementation not only reduced hyperglycemia and pancreatic ?-cell failure but also lowered blood glycosylated hemoglobin and plasma insulin levels. The homeostasis model assessment of insulin resistance levels was also decreased and the decrease seems to be mediated by the lowered activities of hepatic glucose-6-phosphatase and phosphoenolpyruvate carboxykinases. The present data suggest that GE+OE may have the potential to reduce hyperglycemia, insulin resistance, and obesity in patients with type 2 diabetes. PMID:26175996

  2. Role of exercise intensity on GLUT4 content, aerobic fitness and fasting plasma glucose in type 2 diabetic mice.

    PubMed

    Cunha, Verusca Najara; de Paula Lima, Mérica; Motta-Santos, Daisy; Pesquero, Jorge Luiz; de Andrade, Rosangela Vieira; de Almeida, Jeeser Alves; Araujo, Ronaldo Carvalho; Grubert Campbell, Carmen Silvia; Lewis, John E; Simões, Herbert Gustavo

    2015-10-01

    Type 2 diabetes mellitus (T2D) results in several metabolic and cardiovascular dysfunctions, clinically characterized by hyperglycaemia due to lower glucose uptake and oxidation. Physical exercise is an effective intervention for glycaemic control. However, the effects of exercising at different intensities have not yet been addressed. The present study analysed the effects of 8?weeks of training performed at different exercise intensities on type 4 glucose transporters (GLUT4) content and glycaemic control of T2D (ob/ob) and non-diabetic mice (ob/OB). The animals were divided into six groups, with four groups being subjected either to low-intensity (ob/obL and ob/OBL: 3% body weight, three times/week/40?min) or high-intensity (ob/obH and ob/OBH: 6% body weight, three times per week per 20?min) swimming training. An incremental swimming test was performed to measure aerobic fitness. After the training intervention period, glycaemia and the content of GLUT4 were quantified. Although both training intensities were beneficial, the high-intensity regimen induced a more significant improvement in GLUT4 levels and glycaemic profile compared with sedentary controls (p?mice, perhaps because of a higher metabolic demand imposed by this form of exercise. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26467261

  3. Ptpn22 and Cd2 Variations Are Associated with Altered Protein Expression and Susceptibility to Type 1 Diabetes in Nonobese Diabetic Mice.

    PubMed

    Fraser, Heather I; Howlett, Sarah; Clark, Jan; Rainbow, Daniel B; Stanford, Stephanie M; Wu, Dennis J; Hsieh, Yi-Wen; Maine, Christian J; Christensen, Mikkel; Kuchroo, Vijay; Sherman, Linda A; Podolin, Patricia L; Todd, John A; Steward, Charles A; Peterson, Laurence B; Bottini, Nunzio; Wicker, Linda S

    2015-11-15

    By congenic strain mapping using autoimmune NOD.C57BL/6J congenic mice, we demonstrated previously that the type 1 diabetes (T1D) protection associated with the insulin-dependent diabetes (Idd)10 locus on chromosome 3, originally identified by linkage analysis, was in fact due to three closely linked Idd loci: Idd10, Idd18.1, and Idd18.3. In this study, we define two additional Idd loci-Idd18.2 and Idd18.4-within the boundaries of this cluster of disease-associated genes. Idd18.2 is 1.31 Mb and contains 18 genes, including Ptpn22, which encodes a phosphatase that negatively regulates T and B cell signaling. The human ortholog of Ptpn22, PTPN22, is associated with numerous autoimmune diseases, including T1D. We, therefore, assessed Ptpn22 as a candidate for Idd18.2; resequencing of the NOD Ptpn22 allele revealed 183 single nucleotide polymorphisms with the C57BL/6J (B6) allele-6 exonic and 177 intronic. Functional studies showed higher expression of full-length Ptpn22 RNA and protein, and decreased TCR signaling in congenic strains with B6-derived Idd18.2 susceptibility alleles. The 953-kb Idd18.4 locus contains eight genes, including the candidate Cd2. The CD2 pathway is associated with the human autoimmune disease, multiple sclerosis, and mice with NOD-derived susceptibility alleles at Idd18.4 have lower CD2 expression on B cells. Furthermore, we observed that susceptibility alleles at Idd18.2 can mask the protection provided by Idd10/Cd101 or Idd18.1/Vav3 and Idd18.3. In summary, we describe two new T1D loci, Idd18.2 and Idd18.4, candidate genes within each region, and demonstrate the complex nature of genetic interactions underlying the development of T1D in the NOD mouse model. PMID:26438525

  4. Ptpn22 and Cd2 Variations Are Associated with Altered Protein Expression and Susceptibility to Type 1 Diabetes in Nonobese Diabetic Mice

    PubMed Central

    Fraser, Heather I.; Howlett, Sarah; Clark, Jan; Rainbow, Daniel B.; Stanford, Stephanie M.; Wu, Dennis J.; Hsieh, Yi-Wen; Maine, Christian J.; Christensen, Mikkel; Kuchroo, Vijay; Sherman, Linda A.; Podolin, Patricia L.; Todd, John A.; Steward, Charles A.; Peterson, Laurence B.; Bottini, Nunzio

    2015-01-01

    By congenic strain mapping using autoimmune NOD.C57BL/6J congenic mice, we demonstrated previously that the type 1 diabetes (T1D) protection associated with the insulin-dependent diabetes (Idd)10 locus on chromosome 3, originally identified by linkage analysis, was in fact due to three closely linked Idd loci: Idd10, Idd18.1, and Idd18.3. In this study, we define two additional Idd loci—Idd18.2 and Idd18.4—within the boundaries of this cluster of disease-associated genes. Idd18.2 is 1.31 Mb and contains 18 genes, including Ptpn22, which encodes a phosphatase that negatively regulates T and B cell signaling. The human ortholog of Ptpn22, PTPN22, is associated with numerous autoimmune diseases, including T1D. We, therefore, assessed Ptpn22 as a candidate for Idd18.2; resequencing of the NOD Ptpn22 allele revealed 183 single nucleotide polymorphisms with the C57BL/6J (B6) allele—6 exonic and 177 intronic. Functional studies showed higher expression of full-length Ptpn22 RNA and protein, and decreased TCR signaling in congenic strains with B6-derived Idd18.2 susceptibility alleles. The 953-kb Idd18.4 locus contains eight genes, including the candidate Cd2. The CD2 pathway is associated with the human autoimmune disease, multiple sclerosis, and mice with NOD-derived susceptibility alleles at Idd18.4 have lower CD2 expression on B cells. Furthermore, we observed that susceptibility alleles at Idd18.2 can mask the protection provided by Idd10/Cd101 or Idd18.1/Vav3 and Idd18.3. In summary, we describe two new T1D loci, Idd18.2 and Idd18.4, candidate genes within each region, and demonstrate the complex nature of genetic interactions underlying the development of T1D in the NOD mouse model. PMID:26438525

  5. Fumosorinone, a novel PTP1B inhibitor, activates insulin signaling in insulin-resistance HepG2 cells and shows anti-diabetic effect in diabetic KKAy mice.

    PubMed

    Liu, Zhi-Qin; Liu, Ting; Chen, Chuan; Li, Ming-Yan; Wang, Zi-Yu; Chen, Ruo-Song; Wei, Gui-Xiang; Wang, Xiao-Yi; Luo, Du-Qiang

    2015-05-15

    Insulin resistance is a characteristic feature of type 2 diabetes mellitus (T2DM) and is characterized by defects in insulin signaling. Protein tyrosine phosphatase 1B (PTP1B) is a key negative regulator of the insulin signaling pathways, and its increased activity and expression are implicated in the pathogenesis of insulin resistance. Therefore, the inhibition of PTP1B is anticipated to become a potential therapeutic strategy to treat T2DM. Fumosorinone (FU), a new natural product isolated from insect fungi Isaria fumosorosea, was found to inhibit PTP1B activity in our previous study. Herein, the effects of FU on insulin resistance and mechanism in vitro and in vivo were investigated. FU increased the insulin-provoked glucose uptake in insulin-resistant HepG2 cells, and also reduced blood glucose and lipid levels of type 2 diabetic KKAy mice. FU decreased the expression of PTP1B both in insulin-resistant HepG2 cells and in liver tissues of diabetic KKAy mice. Furthermore, FU increased the phosphorylation of IR?, IRS-2, Akt, GSK3? and Erk1/2 in insulin-resistant HepG2 cells, as well as the phosphorylation of IR?, IRS-2, Akt in liver tissues of diabetic KKAy mice. These results showed that FU increased glucose uptake and improved insulin resistance by down-regulating the expression of PTP1B and activating the insulin signaling pathway, suggesting that it may possess antidiabetic properties. PMID:25796170

  6. Human iPS Cell-Derived Insulin Producing Cells Form Vascularized Organoids under the Kidney Capsules of Diabetic Mice

    PubMed Central

    Raikwar, Sudhanshu P.; Kim, Eun-Mi; Sivitz, William I.; Allamargot, Chantal; Thedens, Daniel R.; Zavazava, Nicholas

    2015-01-01

    Type 1 diabetes (T1D) is caused by autoimmune disease that leads to the destruction of pancreatic ?-cells. Transplantation of cadaveric pancreatic organs or pancreatic islets can restore normal physiology. However, there is a chronic shortage of cadaveric organs, limiting the treatment of the majority of patients on the pancreas transplantation waiting list. Here, we hypothesized that human iPS cells can be directly differentiated into insulin producing cells (IPCs) capable of secreting insulin. Using a series of pancreatic growth factors, we successfully generated iPS cells derived IPCs. Furthermore, to investigate the capability of these cells to secrete insulin in vivo, the differentiated cells were transplanted under the kidney capsules of diabetic immunodeficient mice. Serum glucose levels gradually declined to either normal or near normal levels over 150 days, suggesting that the IPCs were secreting insulin. In addition, using MRI, a 3D organoid appeared as a white patch on the transplanted kidneys but not on the control kidneys. These organoids showed neo-vascularization and stained positive for insulin and glucagon. All together, these data show that a pancreatic organ can be created in vivo providing evidence that iPS cells might be a novel option for the treatment of T1D. PMID:25629318

  7. Human iPS cell-derived insulin producing cells form vascularized organoids under the kidney capsules of diabetic mice.

    PubMed

    Raikwar, Sudhanshu P; Kim, Eun-Mi; Sivitz, William I; Allamargot, Chantal; Thedens, Daniel R; Zavazava, Nicholas

    2015-01-01

    Type 1 diabetes (T1D) is caused by autoimmune disease that leads to the destruction of pancreatic ?-cells. Transplantation of cadaveric pancreatic organs or pancreatic islets can restore normal physiology. However, there is a chronic shortage of cadaveric organs, limiting the treatment of the majority of patients on the pancreas transplantation waiting list. Here, we hypothesized that human iPS cells can be directly differentiated into insulin producing cells (IPCs) capable of secreting insulin. Using a series of pancreatic growth factors, we successfully generated iPS cells derived IPCs. Furthermore, to investigate the capability of these cells to secrete insulin in vivo, the differentiated cells were transplanted under the kidney capsules of diabetic immunodeficient mice. Serum glucose levels gradually declined to either normal or near normal levels over 150 days, suggesting that the IPCs were secreting insulin. In addition, using MRI, a 3D organoid appeared as a white patch on the transplanted kidneys but not on the control kidneys. These organoids showed neo-vascularization and stained positive for insulin and glucagon. All together, these data show that a pancreatic organ can be created in vivo providing evidence that iPS cells might be a novel option for the treatment of T1D. PMID:25629318

  8. Niche-dependent regulations of metabolic balance in high-fat diet-induced diabetic mice by mesenchymal stromal cells.

    PubMed

    Ji, Andrea Tung-Qian; Chang, Yun-Chuang; Fu, Yun-Ju; Lee, Oscar K; Ho, Jennifer H

    2015-03-01

    Mesenchymal stromal cells (MSCs) have great potential to maintain glucose homeostasis and metabolic balance. Here, we demonstrate that in mice continuously fed with high-fat diet (HFD) that developed non-insulin-dependent diabetes, two episodes of systemic MSC transplantations effectively improve glucose tolerance and blood glucose homeostasis and reduce body weight through targeting pancreas and insulin-sensitive tissues and organs via site-specific mechanisms. MSCs support pancreatic islet growth by direct differentiation into insulin-producing cells and by mitigating the cytotoxicity of interleukin 1 (IL-1) and tumor necrosis factor-? (TNF-?) in the pancreas. Localization of MSCs in the liver and skeletal muscles in diabetic animals is also enhanced and therefore improves glucose tolerance, although long-term engraftment is not observed. MSCs prevent HFD-induced fatty liver development and restore glycogen storage in hepatocytes. Increased expression of IL-1 receptor antagonist and Glut4 in skeletal muscles after MSC transplantation results in better blood glucose homeostasis. Intriguingly, systemic MSC transplantation does not alter adipocyte number, but it decreases HFD-induced cell infiltration in adipose tissues and reduces serum levels of adipokines, including leptin and TNF-?. Taken together, systemic MSC transplantation ameliorates HFD-induced obesity and restores metabolic balance through multisystemic regulations that are niche dependent. Such findings have supported systemic transplantation of MSCs to correct metabolic imbalance. PMID:25277392

  9. SGLT2 inhibitor empagliflozin reduces renal growth and albuminuria in proportion to hyperglycemia and prevents glomerular hyperfiltration in diabetic Akita mice.

    PubMed

    Vallon, Volker; Gerasimova, Maria; Rose, Michael A; Masuda, Takahiro; Satriano, Joseph; Mayoux, Eric; Koepsell, Hermann; Thomson, Scott C; Rieg, Timo

    2014-01-01

    Our previous work has shown that gene knockout of the sodium-glucose cotransporter SGLT2 modestly lowered blood glucose in streptozotocin-diabetic mice (BG; from 470 to 300 mg/dl) and prevented glomerular hyperfiltration but did not attenuate albuminuria or renal growth and inflammation. Here we determined effects of the SGLT2 inhibitor empagliflozin (300 mg/kg of diet for 15 wk; corresponding to 60-80 mg·kg(-1)·day(-1)) in type 1 diabetic Akita mice that, opposite to streptozotocin-diabetes, upregulate renal SGLT2 expression. Akita diabetes, empagliflozin, and Akita + empagliflozin similarly increased renal membrane SGLT2 expression (by 38-56%) and reduced the expression of SGLT1 (by 33-37%) vs. vehicle-treated wild-type controls (WT). The diabetes-induced changes in SGLT2/SGLT1 protein expression are expected to enhance the BG-lowering potential of SGLT2 inhibition, and empagliflozin strongly lowered BG in Akita (means of 187-237 vs. 517-535 mg/dl in vehicle group; 100-140 mg/dl in WT). Empagliflozin modestly reduced GFR in WT (250 vs. 306 ?l/min) and completely prevented the diabetes-induced increase in glomerular filtration rate (GFR) (255 vs. 397 ?l/min). Empagliflozin attenuated increases in kidney weight and urinary albumin/creatinine ratio in Akita in proportion to hyperglycemia. Empagliflozin did not increase urinary glucose/creatinine ratios in Akita, indicating the reduction in filtered glucose balanced the inhibition of glucose reabsorption. Empagliflozin attenuated/prevented the increase in systolic blood pressure, glomerular size, and molecular markers of kidney growth, inflammation, and gluconeogenesis in Akita. We propose that SGLT2 inhibition can lower GFR independent of reducing BG (consistent with the tubular hypothesis of diabetic glomerular hyperfiltration), while attenuation of albuminuria, kidney growth, and inflammation in the early diabetic kidney may mostly be secondary to lower BG. PMID:24226524

  10. Novel Small Molecule Agonist of TGR5 Possesses Anti-Diabetic Effects but Causes Gallbladder Filling in Mice

    PubMed Central

    Briere, Daniel A.; Ruan, Xiaoping; Cheng, Christine C.; Siesky, Angela M.; Fitch, Thomas E.; Dominguez, Carmen; Sanfeliciano, Sonia Gutierrez; Montero, Carlos; Suen, Chen S.; Xu, Yanping; Coskun, Tamer; Michael, M. Dodson

    2015-01-01

    Activation of TGR5 via bile acids or bile acid analogs leads to the release of glucagon-like peptide-1 (GLP-1) from intestine, increases energy expenditure in brown adipose tissue, and increases gallbladder filling with bile. Here, we present compound 18, a non-bile acid agonist of TGR5 that demonstrates robust GLP-1 secretion in a mouse enteroendocrine cell line yet weak GLP-1 secretion in a human enteroendocrine cell line. Acute administration of compound 18 to mice increased GLP-1 and peptide YY (PYY) secretion, leading to a lowering of the glucose excursion in an oral glucose tolerance test (OGTT), while chronic administration led to weight loss. In addition, compound 18 showed a dose-dependent increase in gallbladder filling. Lastly, compound 18 failed to show similar pharmacological effects on GLP-1, PYY, and gallbladder filling in Tgr5 knockout mice. Together, these results demonstrate that compound 18 is a mouse-selective TGR5 agonist that induces GLP-1 and PYY secretion, and lowers the glucose excursion in an OGTT, but only at doses that simultaneously induce gallbladder filling. Overall, these data highlight the benefits and potential risks of using TGR5 agonists to treat diabetes and metabolic diseases. PMID:26312995

  11. A tripeptide Diapin effectively lowers blood glucose levels in male type 2 diabetes mice by increasing blood levels of insulin and GLP-1.

    PubMed

    Zhang, Jifeng; Xue, Changyong; Zhu, Tianqing; Vivekanandan, Anuradha; Pennathur, Subramaniam; Ma, Zhongmin Alex; Chen, Y Eugene

    2013-01-01

    The prevalence of type 2 diabetes (T2D) is rapidly increasing worldwide. Effective therapies, such as insulin and Glucagon-like peptide-1 (GLP-1), require injections, which are costly and result in less patient compliance. Here, we report the identification of a tripeptide with significant potential to treat T2D. The peptide, referred to as Diapin, is comprised of three natural L-amino acids, GlyGlyLeu. Glucose tolerance tests showed that oral administration of Diapin effectively lowered blood glucose after oral glucose loading in both normal C57BL/6J mice and T2D mouse models, including KKay, db/db, ob/ob mice, and high fat diet-induced obesity/T2D mice. In addition, Diapin treatment significantly reduced casual blood glucose in KKay diabetic mice in a time-dependent manner without causing hypoglycemia. Furthermore, we found that plasma GLP-1 and insulin levels in diabetic models were significantly increased with Diapin treatment compared to that in the controls. In summary, our findings establish that a peptide with minimum of three amino acids can improve glucose homeostasis and Diapin shows promise as a novel pharmaceutical agent to treat patients with T2D through its dual effects on GLP-1 and insulin secretion. PMID:24386218

  12. Effects of ingested turmeric oleoresin on glucose and lipid metabolisms in obese diabetic mice: a DNA microarray study.

    PubMed

    Honda, Shinichi; Aoki, Fumiki; Tanaka, Hozumi; Kishida, Hideyuki; Nishiyama, Tozo; Okada, Shinji; Matsumoto, Ichiro; Abe, Keiko; Mae, Tatsumasa

    2006-11-29

    Turmeric, the rhizome of Curcuma longa L., has a wide range of effects on human health. Turmeric oleoresin, an extract of turmeric, is often used for flavoring and coloring. Curcuminoids and turmeric essential oil are both contained in turmeric oleoresin, and both of these fractions have hypoglycemic effects. In the present study, we comprehensively assessed the effect of turmeric oleoresin on hepatic gene expression in obese diabetic KK-Ay mice using DNA microarray analysis and quantitative real-time polymerase chain reaction (PCR). Female KK-Ay mice aged 6 weeks (n = 6/group) were fed a high-fat diet containing turmeric oleoresin, curcuminoids, and essential oil for 5 weeks. The same diet without any of these fractions was used as a control diet. Ingestion of turmeric oleoresin and essential oil inhibited the development of increased blood glucose and abdominal fat mass, while curcuminoids only inhibited the increase in blood glucose. DNA microarray analysis indicated that turmeric oleoresin ingestion up-regulated the expression of genes related to glycolysis, beta-oxidation, and cholesterol metabolism in the liver of KK-Ay mice, while expression of gluconeogenesis-related genes was down-regulated. Real-time PCR analysis was conducted to assess the contribution of the curcuminoids and essential oil in turmeric oleoresin to the changes in expression of representative genes selected by DNA microarray analysis. This analysis suggested that curcuminoids regulated turmeric oleoresin ingestion-induced expression of glycolysis-related genes and also that curcuminoids and turmeric essential oil acted synergistically to regulate the peroxisomal beta-oxidation-related gene expression induced by turmeric oleoresin ingestion. These changes in gene expression were considered to be the mechanism by which the turmeric oleoresin affected the control of both blood glucose levels and abdominal adipose tissue masses. All of these results suggest that the use of whole turmeric oleoresin is more effective than the use of either curcuminoids or the essential oil alone. PMID:17117790

  13. Combining MK626, a Novel DPP-4 Inhibitor, and Low-Dose Monoclonal CD3 Antibody for Stable Remission of New-Onset Diabetes in Mice

    PubMed Central

    Ding, Lei; Gysemans, Conny A.; Stangé, Geert; Heremans, Yves; Yuchi, Yixing; Takiishi, Tatiana; Korf, Hannelie; Chintinne, Marie; Carr, Richard D.; Heimberg, Harry; Pipeleers, Daniel; Mathieu, Chantal

    2014-01-01

    Combining immune intervention with therapies that directly influence the functional state of the ?-cells is an interesting strategy in type 1 diabetes cure. Dipeptidyl peptidase-4 (DPP-4) inhibitors elevate circulating levels of active incretins, which have been reported to enhance insulin secretion and synthesis, can support ?-cell survival and possibly stimulate ?-cell proliferation and neogenesis. In the current study, we demonstrate that the DPP-4 inhibitor MK626, which has appropriate pharmacokinetics in mice, preceded by a short-course of low-dose anti-CD3 generated durable diabetes remission in new-onset diabetic non-obese diabetic (NOD) mice. Induction of remission involved recovery of ?-cell secretory function with resolution of destructive insulitis and preservation of ?-cell volume/mass, along with repair of the islet angioarchitecture via SDF-1- and VEGF-dependent actions. Combination therapy temporarily reduced the CD4-to-CD8 distribution in spleen although not in pancreatic draining lymph nodes (PLN) and increased the proportion of effector/memory T cells as did anti-CD3 alone. In contrast, only combination therapy amplified Foxp3+ regulatory T cells in PLN and locally in pancreas. These findings open new opportunities for the treatment of new-onset type 1 diabetes by introducing DPP-4 inhibitors in human CD3-directed clinical trials. PMID:25268801

  14. Short-Term Environmental Enrichment Enhances Adult Neurogenesis, Vascular Network and Dendritic Complexity in the Hippocampus of Type 1 Diabetic Mice

    PubMed Central

    Beauquis, Juan; Roig, Paulina; De Nicola, Alejandro F.; Saravia, Flavia

    2010-01-01

    Background Several brain disturbances have been described in association to type 1 diabetes in humans. In animal models, hippocampal pathological changes were reported together with cognitive deficits. The exposure to a variety of environmental stimuli during a certain period of time is able to prevent brain alterations and to improve learning and memory in conditions like stress, aging and neurodegenerative processes. Methodology/Principal Findings We explored the modulation of hippocampal alterations in streptozotocin-induced type 1 diabetic mice by environmental enrichment. In diabetic mice housed in standard conditions we found a reduction of adult neurogenesis in the dentate gyrus, decreased dendritic complexity in CA1 neurons and a smaller vascular fractional area in the dentate gyrus, compared with control animals in the same housing condition. A short exposure -10 days- to an enriched environment was able to enhance proliferation, survival and dendritic arborization of newborn neurons, to recover dendritic tree length and spine density of pyramidal CA1 neurons and to increase the vascular network of the dentate gyrus in diabetic animals. Conclusions/Significance The environmental complexity seems to constitute a strong stimulator competent to rescue the diabetic brain from neurodegenerative progression. PMID:21085588

  15. Anti-diabetic potential of the essential oil of Pinus koraiensis leaves toward streptozotocin-treated mice and HIT-T15 pancreatic ? cells.

    PubMed

    Joo, Hye-Eun; Lee, Hyo-Jung; Sohn, Eun Jung; Lee, Min-Ho; Ko, Hyun-Suk; Jeong, Soo-Jin; Lee, Hyo-Jeong; Kim, Sung-Hoon

    2013-01-01

    The metabolic syndrome creates risk factors for coronary heart disease, diabetes, fatty liver, obesity and several cancers. Our group has already reported that the essential oil from leaves of Pinus koraiensis SIEB (EOPK) exerted antihyperlipidemic effects by upregulating the low-density lipoprotein receptor and inhibiting acyl-coenzyme A, cholesterol acyltransferases. We evaluated in the current study the anti-diabetic effects of EOPK on mice with streptozotocin (STZ)-induced type I diabetes and on HIT-T15 pancreatic ? cells. EOPK significantly protected HIT-T15 cells from STZ-induced cytotoxicity and reduced the blood glucose level in STZ-induced diabetic mice when compared with the untreated control. EOPK consistently and significantly suppressed the ?-amylase activity in a dose-dependent manner and enhanced the expression of insulin at the mRNA level in STZ-treated HIT-T15 cells, while the expression of insulin was attenuated. EOPK also significantly abrogated the population of reactive oxygen species when compared to the untreated control in STZ-treated HIT-T15 cells. Furthermore, EOPK significantly reduce nitric oxide production, suppressed the phosphorylation of endothelial nitric oxide (NO) synthase and suppressed the production of vascular endothelial growth factor (VEGF) in STZ-treated HIT-T15 cells, implying its potential application to diabetic retinopathy. Overall, our findings suggest that EOPK had hypoglycemic potential by inhibiting reactive oxygene species (ROS), endothelial NO synthase (eNOS) and VEGF in STZ-treated mice and HIT-T15 pancreatic ? cells as a potent anti-diabetic agent. PMID:24096647

  16. Beneficial effect of the soluble guanylyl cyclase stimulator BAY 41-2272 on impaired penile erection in db/db-/- type II diabetic and obese mice.

    PubMed

    Nunes, Kenia Pedrosa; Teixeira, Cleber E; Priviero, Fernanda B M; Toque, Haroldo A; Webb, R Clinton

    2015-05-01

    Type 2 diabetes mellitus (DM2) and obesity are major risk factors for erectile dysfunction (ED). In diabetes, increased oxidative stress leads to decreased nitric oxide (NO) bioavailability, and diabetic patients appear to be less responsive to conventional therapy with phosphodiesterase type 5 inhibitors. We investigated whether the soluble guanylyl cyclase stimulator BAY 41-2272 (5-cyclopropyl-2-[1-(2-fluoro-benzyl)-1H-pyrazolo[3,4-b]pyridine-3-yl]pyrimidin-4ylamine) is effective in improving impaired corpus cavernosum (CC) relaxation in obese DM2 mice by reducing oxidative stress. Adult db/db(-/-) mice or their lean db(/+) littermates were used to assess vascular function, cGMP levels, antioxidant status, NADPH oxidase expression, and superoxide formation in the absence or presence of BAY 41-2272. Results showed that BAY 41-2272 (10(-8) to 10(-5) M) potently relaxed CC from db(/+) or db/db(-/-) mice in a similar manner. BAY 41-2272 significantly enhanced both endothelium-dependent and nitrergic relaxation induced by electrical field stimulation (EFS), and improved the impaired relaxation to acetylcholine and EFS in the diabetic animals in a concentration-dependent manner (10(-8) to 10(-7) M). BAY 41-2272 increased cGMP levels and potentiated relaxation responses to exogenous NO in CC. Total antioxidant status was reduced in plasma and urine whereas expression of vascular NADPH oxidase subunits (gp91phox, p22phox, and p47phox) was increased in the CC of db/db(-/-) mice, suggesting a state of oxidative stress. These effects were prevented by BAY 41-2272 in a concentration-dependent manner. These results suggest that BAY 41-2272 improves CC relaxation in db/db(-/-) mice by increasing cGMP and augmenting antioxidant status, making this drug is a potential novel candidate to treat ED. PMID:25740897

  17. Beneficial metabolic actions of a stable GIP agonist following pre-treatment with a SGLT2 inhibitor in high fat fed diabetic mice.

    PubMed

    Millar, P J B; Pathak, V; Moffett, R C; Pathak, N M; Bjourson, A J; O'Kane, M J; Flatt, P R; Gault, V A

    2016-01-15

    The purpose of the present study was to examine if a stable glucose-dependent insulinotropic polypeptide (GIP) agonist could exert beneficial metabolic control in diabetic mice which had been pre-treated with sodium-glucose-cotransporter-2 (SGLT2) inhibitor dapagliflozin (DAPA). High fat fed mice administered low dose streptozotocin (STZ) received vehicle, DAPA once-daily over 28 days, or DAPA once-daily for 14 days followed by (dAla(2))GIP once-daily for 14 days. Energy intake, body weight, glucose and insulin concentrations were measured at regular intervals. Glucose tolerance, insulin tolerance test, dual-energy X-ray absorptiometry (DEXA) and pancreatic histology were examined. Once-daily administration of (dAla(2))GIP for 14 days in high fat fed diabetic mice pre-treated with DAPA demonstrated significant decrease in body weight, blood glucose and increased insulin concentrations which were independent of changes in energy intake. Similarly, glucose tolerance, glucose-stimulated insulin secretion, insulin sensitivity and HOMA-? were significantly enhanced in (dAla(2))GIP-treated mice. DEXA analysis revealed sustained percentage body fat loss with no changes in lean mass, bone mineral content and density. Pancreatic immunohistochemical analysis revealed decreased islet number and increases in islet area, beta cell area and pancreatic insulin content. The DAPA-induced increase in alpha cell area was also reversed. Additional acute in vitro and in vivo experiments confirmed that the impaired action of (dAla(2))GIP under hyperglycaemic-induced conditions was significantly reversed by DAPA treatment. These data demonstrate that (dAla(2))GIP can exert beneficial metabolic control in high fat fed diabetic mice pre-treated with DAPA. The results highlight possibility of a targeted and personalized approach using a GIP agonist and SGLT2 inhibitor for the treatment of type 2 diabetes. PMID:26607806

  18. Bile acid signaling in lipid metabolism: metabolomic and lipidomic analysis of lipid and bile acid markers linked to anti-obesity and anti-diabetes in mice.

    PubMed

    Qi, Yunpeng; Jiang, Changtao; Cheng, Jie; Krausz, Kristopher W; Li, Tiangang; Ferrell, Jessica M; Gonzalez, Frank J; Chiang, John Y L

    2015-01-01

    Bile acid synthesis is the major pathway for catabolism of cholesterol. Cholesterol 7?-hydroxylase (CYP7A1) is the rate-limiting enzyme in the bile acid biosynthetic pathway in the liver and plays an important role in regulating lipid, glucose and energy metabolism. Transgenic mice overexpressing CYP7A1 (CYP7A1-tg mice) were resistant to high-fat diet (HFD)-induced obesity, fatty liver, and diabetes. However the mechanism of resistance to HFD-induced obesity of CYP7A1-tg mice has not been determined. In this study, metabolomic and lipidomic profiles of CYP7A1-tg mice were analyzed to explore the metabolic alterations in CYP7A1-tg mice that govern the protection against obesity and insulin resistance by using ultra-performance liquid chromatography-coupled with electrospray ionization quadrupole time-of-flight mass spectrometry combined with multivariate analyses. Lipidomics analysis identified seven lipid markers including lysophosphatidylcholines, phosphatidylcholines, sphingomyelins and ceramides that were significantly decreased in serum of HFD-fed CYP7A1-tg mice. Metabolomics analysis identified 13 metabolites in bile acid synthesis including taurochenodeoxycholic acid, taurodeoxycholic acid, tauroursodeoxycholic acid, taurocholic acid, and tauro-?-muricholic acid (T-?-MCA) that differed between CYP7A1-tg and wild-type mice. Notably, T-?-MCA, an antagonist of the farnesoid X receptor (FXR) was significantly increased in intestine of CYP7A1-tg mice. This study suggests that reducing 12?-hydroxylated bile acids and increasing intestinal T-?-MCA may reduce high fat diet-induced increase of phospholipids, sphingomyelins and ceramides, and ameliorate diabetes and obesity. This article is part of a Special Issue entitled Linking transcription to physiology in lipodomics. PMID:24796972

  19. An update on the use of NOD mice to study autoimmune (Type 1) diabetes

    PubMed Central

    Chaparro, Rodolfo José; DiLorenzo, Teresa P

    2011-01-01

    The widely used nonobese diabetic (NOD) mouse model of autoimmune (Type 1) diabetes mellitus shares multiple characteristics with the human disease, and studies employing this model continue to yield clinically relevant and important information. Here, we review some of the recent key findings obtained from NOD mouse investigations that have both advanced our understanding of disease pathogenesis and suggested new therapeutic targets and approaches. Areas discussed include antigen discovery, identification of genes and pathways contributing to disease susceptibility, development of strategies to image islet inflammation and the testing of therapeutics. We also review recent technical advances that, combined with an improved understanding of the NOD mouse model’s limitations, should work to ensure its popularity, utility and relevance in the years ahead. PMID:20979558

  20. Stabilization of HIF-1? is critical to improve wound healing in diabetic mice

    PubMed Central

    Botusan, Ileana Ruxandra; Sunkari, Vivekananda Gupta; Savu, Octavian; Catrina, Anca Irinel; Grünler, Jacob; Lindberg, Stina; Pereira, Teresa; Ylä-Herttuala, Seppo; Poellinger, Lorenz; Brismar, Kerstin; Catrina, Sergiu-Bogdan

    2008-01-01

    Relative hypoxia is essential in wound healing since it normally plays a pivotal role in regulation of all the critical processes involved in tissue repair. Hypoxia-inducible factor (HIF) 1? is the critical transcription factor that regulates adaptive responses to hypoxia. HIF-1? stability and function is regulated by oxygen-dependent soluble hydroxylases targeting critical proline and asparaginyl residues. Here we show that hyperglycemia complexly affects both HIF-1? stability and activation, resulting in suppression of expression of HIF-1 target genes essential for wound healing both in vitro and in vivo. However, by blocking HIF-1? hydroxylation through chemical inhibition, it is possible to reverse this negative effect of hyperglycemia and to improve the wound healing process (i.e., granulation, vascularization, epidermal regeneration, and recruitment of endothelial precursors). Local adenovirus-mediated transfer of two stable HIF constructs demonstrated that stabilization of HIF-1? is necessary and sufficient for promoting wound healing in a diabetic environment. Our findings outline the necessity to develop specific hydroxylase inhibitors as therapeutic agents for chronic diabetes wounds. In conclusion, we demonstrate that impaired regulation of HIF-1? is essential for the development of diabetic wounds, and we provide evidence that stabilization of HIF-1? is critical to reverse the pathological process. PMID:19057015

  1. Genetic Analysis of Substrain Divergence in Non-Obese Diabetic (NOD) Mice

    PubMed Central

    Simecek, Petr; Churchill, Gary A.; Yang, Hyuna; Rowe, Lucy B.; Herberg, Lieselotte; Serreze, David V.; Leiter, Edward H.

    2015-01-01

    The non-obese diabetic (NOD) mouse is a polygenic model for type 1 diabetes that is characterized by insulitis, a leukocytic infiltration of the pancreatic islets. During ~35 years since the original inbred strain was developed in Japan, NOD substrains have been established at different laboratories around the world. Although environmental differences among NOD colonies capable of impacting diabetes incidence have been recognized, differences arising from genetic divergence have not been analyzed previously. We use both mouse diversity array and whole-exome capture sequencing platforms to identify genetic differences distinguishing five NOD substrains. We describe 64 single-nucleotide polymorphisms, and two short indels that differ in coding regions of the five NOD substrains. A 100-kb deletion on Chromosome 3 distinguishes NOD/ShiLtJ and NOD/ShiLtDvs from three other substrains, whereas a 111-kb deletion in the Icam2 gene on Chromosome 11 is unique to the NOD/ShiLtDvs genome. The extent of genetic divergence for NOD substrains is compared with similar studies for C57BL6 and BALB/c substrains. As mutations are fixed to homozygosity by continued inbreeding, significant differences in substrain phenotypes are to be expected. These results emphasize the importance of using embryo freezing methods to minimize genetic drift within substrains and of applying appropriate genetic nomenclature to permit substrain recognition when one is used. PMID:25740934

  2. Topical Application of Insulin Accelerates Vessel Maturation of Wounds by Regulating Angiopoietin-1 in Diabetic Mice.

    PubMed

    Li, Chaofei; Yu, Tianyi; Liu, Yan; Chen, Xuelian; Zhang, Xiong

    2015-12-01

    Reestablishment of the structural and functional microvasculature would be beneficial to promote healing of diabetic wounds. We explored the role of insulin application on microvascular maturation of diabetic wounds to determine whether it is associated with insulin-induced wound healing. We adopted the multiple injections of streptozotocin (STZ) to establish a diabetic animal model. The effect of insulin on microvessel formation, especially the effect of insulin on microvascular maturation was observed by transmission electron microscopy and laser scanning confocal microscopy. The pivotal protein regulated by insulin during healing processes was explored by tropical application neutralizing antibodies to these proteins; the specific protein was further confirmed using immunoblotting. On days 7 and 11, the blood vessel in insulin-treated wounds was surrounded by more ?-smooth muscle actin (?-SMA) expressing cells. The blockage of angiopoietin-1 (Ang-1), but not angiopoietin-2 (Ang-2) or platelet-derived growth factor-B (PDGF-B), resulted in reduced maturation of newly formed blood vessels despite the presence of insulin in vivo. Further analysis showed that insulin induced an increased expression of Ang-1. The blood vessels in insulin-treated wounds showing advanced coverage of pericytes and reconstruction of new vascular basement membrane suggest that insulin is a potent accelerator of microvascular maturation, which may be involved in the mechanisms of insulin-induced wound healing. PMID:26349856

  3. Hypoglycaemic effects of tea extracts and ent-kaurenoic acid from Smallanthus sonchifolius.

    PubMed

    Raga, Dennis D; Alimboyoguen, Agnes B; del Fierro, Ramon S; Ragasa, Consolacion Y

    2010-11-01

    Hypoglycaemic activity was observed in normoglycaemic mice orally administered with the aqueous Smallanthus sonchifolius leaf tea extract, alloxan-induced diabetic mice orally administered with ent-kaurenoic acid (1), and normoglycaemic mice intraperitoneally administered with 1 from S. sonchifolius leaves. A single dose administration of 50 mg kg(-1) BW yacon leaf tea extract demonstrated immediate but relatively short hypoglycaemic activity, with significant effects observed during 1-2 h. Similarly, administration with 100 mg kg(-1) BW yacon leaf tea extract obtained by heavy stirring in hot water demonstrated a more potent activity compared to the positive control at 1.5-2.0 h. Oral administration of 1 did not affect the blood glucose level of the alloxan-induced diabetic mice, but a single intraperitonial injection of 10 mg kg(-1) BW in normoglycaemic mice had consistent percent blood glucose reduction persisting from 1 to 2 h observation periods. PMID:20981618

  4. Hypoglycemic action of Cyclocarya paliurus (Batal.) Iljinskaja in normal and diabetic mice.

    PubMed

    Kurihara, Hiroshi; Fukami, Harukazu; Kusumoto, Aki; Toyoda, Yoshiko; Shibata, Hiroshi; Matsui, Yokichi; Asami, Sumio; Tanaka, Takaharu

    2003-04-01

    This study examined the hypoglycaemic activity of Cyclocarya paliurus (Batal.) Iljinskaja (C. paliurus) in ICR mice by oral glucose tolerance testing. The blood glucose level was significantly lower in the C. paliurus extract treatment group than in the control group after animals were given sucrose. This difference was not observed following the administration of glucose. We demonstrated that the chronological change in the level of blood glucose in genetically hyperglycemic obese KK-Ay mice is significantly lower when C. paliurus extract is administered daily for three weeks. An in vitro study showed that C. paliurus inhibits alpha-glucosidase, a disaccharide-degrading enzyme in the small intestinal mucosa, leading to a decrease in the absorption of glucose into the blood and a subsequent lowering of the blood glucose level. PMID:12784631

  5. Effect of Momordica dioica fruit extract on antioxidant status in liver, kidney, pancreas, and serum of diabetic rats

    PubMed Central

    Sharma, Poonam; Singh, Rambir

    2014-01-01

    Background: Fruits, leaves, and tuberous roots of Momordica dioica are used as a folk remedy for diabetes mellitus (DM) in India. The aqueous extract of Momordica dioica fruit possesses very good anti-diabetic activity and is having high margin of safety. Objectives: The aim of the present study was to investigate the antioxidative effect of Momordica dioica fruits in alloxan-induced diabetic Wistar rats. Materials and Methods: Effect of aqueous extract of Momordica dioica (AEMD) on thiobarbituric acid reactive substances (TBARS), hydroperoxide (HP), non-enzymatic and enzymatic antioxidants in liver, kidney, pancreas, and serum was evaluated in diabetic rats after 21 days treatment. Results: Increase in the levels of TBARS, HP and decrease in the levels of non-enzymatic antioxidants and activity of enzymatic antioxidants was observed in liver, kidney, pancreas, and serum of diabetic rats when compared with normal healthy rats. TBARS and HP levels were reduced while non-enzymatic and enzymatic antioxidant enzymes activity was increased in AEMD and glibenclamide-treated rats. Furthermore, histological examination of liver, kidney, and pancreas of diabetic rats showed degenerative changes. AEMD treatment for 21 days rejuvenated liver, kidney, and pancreas histoarchitecture. Conclusion: In conclusion, the present results showed the protective role of AEMD on liver, kidney, and pancreas in severe diabetic rats justifying support for its anti-diabetic use in folk medicine. PMID:24497747

  6. Sulforaphane prevents the development of cardiomyopathy in type 2 diabetic mice probably by reversing oxidative stress-induced inhibition of LKB1/AMPK pathway.

    PubMed

    Zhang, Zhiguo; Wang, Shudong; Zhou, Shanshan; Yan, Xiaoqing; Wang, Yonggang; Chen, Jing; Mellen, Nicholas; Kong, Maiying; Gu, Junlian; Tan, Yi; Zheng, Yang; Cai, Lu

    2014-12-01

    Type 2 diabetes mellitus (T2DM)-induced cardiomyopathy is associated with cardiac oxidative stress, inflammation, and remodeling. Sulforaphane (SFN), an isothiocyanate naturally presenting in widely consumed vegetables, particularly broccoli, plays an important role in cardiac protection from diabetes. We investigated the effect of SFN on T2DM-induced cardiac lipid accumulation and subsequent cardiomyopathy. Male C57BL/6J mice were fed a high-fat diet for 3months to induce insulin resistance, followed by a treatment with 100mg/kg body-weight streptozotocin to induce hyperglycemia; we referred to it as the T2DM mouse model. Other age-matched mice were fed a normal diet as control. T2DM and control mice were treated with or without 4-month SFN at 0.5mg/kg daily five days a week. At the study's end, cardiac function was assessed. SFN treatment significantly attenuated cardiac remodeling and dysfunction induced by T2DM. SFN treatment also significantly inhibited cardiac lipid accumulation, measured by Oil Red O staining, and improved cardiac inflammation oxidative stress and fibrosis, shown by down-regulating diabetes-induced PAI-1, TNF-?, CTGF, TGF-?, 3-NT, and 4-HNE expression. Elevated 4-HNE resulted in the increase of 4-HNE-LKB1 adducts that should inhibit LKB1 and subsequent AMPK activity. SFN upregulated the expression of Nrf2 and its downstream genes, NQO1 and HO-1, decreased 4-HNE-LKB1 adducts and then reversed diabetes-induced inhibition of LKB1/AMPK and its downstream targets, including sirtuin 1, PGC-1?, phosphorylated acetyl-CoA carboxylase, carnitine palmitoyl transferase-1, ULK1, and light chain-3 II. These results suggest that SFN treatment to T2DM mice may attenuate the cardiac oxidative stress-induced inhibition of LKB1/AMPK signaling pathway, thereby preventing T2DM-induced lipotoxicity and cardiomyopathy. PMID:25268649

  7. Irisin inhibits hepatic gluconeogenesis and increases glycogen synthesis via the PI3K/Akt pathway in type 2 diabetic mice and hepatocytes.

    PubMed

    Liu, Tong-Yan; Shi, Chang-Xiang; Gao, Run; Sun, Hai-Jian; Xiong, Xiao-Qing; Ding, Lei; Chen, Qi; Li, Yue-Hua; Wang, Jue-Jin; Kang, Yu-Ming; Zhu, Guo-Qing

    2015-11-01

    Increased glucose production and reduced hepatic glycogen storage contribute to metabolic abnormalities in diabetes. Irisin, a newly identified myokine, induces the browning of white adipose tissue, but its effects on gluconeogenesis and glycogenesis are unknown. In the present study, we investigated the effects and underlying mechanisms of irisin on gluconeogenesis and glycogenesis in hepatocytes with insulin resistance, and its therapeutic role in type 2 diabetic mice. Insulin resistance was induced by glucosamine (GlcN) or palmitate in human hepatocellular carcinoma (HepG2) cells and mouse primary hepatocytes. Type 2 diabetes was induced by streptozotocin/high-fat diet (STZ/HFD) in mice. In HepG2 cells, irisin ameliorated the GlcN-induced increases in glucose production, phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) expression, and glycogen synthase (GS) phosphorylation; it prevented GlcN-induced decreases in glycogen content and the phosphoinositide 3-kinase (PI3K) p110? subunit level, and the phosphorylation of Akt/protein kinase B, forkhead box transcription factor O1 (FOXO1) and glycogen synthase kinase-3 (GSK3). These effects of irisin were abolished by the inhibition of PI3K or Akt. The effects of irisin were confirmed in mouse primary hepatocytes with GlcN-induced insulin resistance and in human HepG2 cells with palmitate-induced insulin resistance. In diabetic mice, persistent subcutaneous perfusion of irisin improved the insulin sensitivity, reduced fasting blood glucose, increased GSK3 and Akt phosphorylation, glycogen content and irisin level, and suppressed GS phosphorylation and PEPCK and G6Pase expression in the liver. Irisin improves glucose homoeostasis by reducing gluconeogenesis via PI3K/Akt/FOXO1-mediated PEPCK and G6Pase down-regulation and increasing glycogenesis via PI3K/Akt/GSK3-mediated GS activation. Irisin may be regarded as a novel therapeutic strategy for insulin resistance and type 2 diabetes. PMID:26201094

  8. Diabetic mice are protected from normally lethal nephrotoxicity of S-1,2-dichlorovinyl-L-cysteine (DCVC): role of nephrogenic tissue repair

    SciTech Connect

    Dnyanmote, Ankur V.; Sawant, Sharmilee P.; Lock, Edward A.; Latendresse, John R.; Warbritton, Alan A.; Mehendale, Harihara M. . E-mail: mehendale@ulm.edu

    2006-03-01

    Streptozotocin (STZ)-induced diabetic (DB) rats are protected from nephrotoxicity of gentamicin, cisplatin and mercuric chloride, although the mechanisms remain unclear. Ninety percent of DB mice receiving a LD90 dose (75 mg/kg, ip) of S-1,2-dichlorovinyl-L-cysteine (DCVC) survived in contrast to only 10% of the nondiabetic (NDB) mice surviving the same dose. We tested the hypothesis that the mechanism of protection is upregulated tissue repair. In the NDB mice, DCVC produced steep temporal increases in blood urea nitrogen (BUN) and plasma creatinine, which were associated with proximal tubular cell (PTC) necrosis, acute renal failure (ARF), and death within 48 h. In contrast, in the DB mice, BUN and creatinine increased less steeply, declining after 36 h to completely resolve by 96 h. HPLC analysis of plasma and urine revealed that DB did not alter the toxicokinetics of DCVC. Furthermore, activity of renal cysteine conjugate {beta}-lyase, the enzyme that bioactivates DCVC, was unaltered in DB mice, undermining the possibility of lower bioactivation of DCVC leading to lower injury. [3H]-thymidine pulse labeling and PCNA analysis indicated an early onset and sustained nephrogenic tissue repair in DCVC-treated DB mice. BRDU immunohistochemistry revealed a fourfold increase in the number of cells in S-phase in the DB kidneys even without exposure to DCVC. Blocking the entry of cells into S-phase by antimitotic intervention using colchicine abolished stimulated nephrogenic tissue repair and nephroprotection. These findings suggest that preplacement of S-phase cells in the kidney due to diabetes is critical in mitigating the progression of DCVC-initiated renal injury by upregulation of tissue repair, leading to survival of the DB mice by avoiding acute renal failure.

  9. Therapeutic window of globular adiponectin against cerebral ischemia in diabetic mice: the role of dynamic alteration of adiponectin/adiponectin receptor expression

    PubMed Central

    Song, Wenying; Guo, Fan; Zhong, Haixing; Liu, Lixin; Yang, Rui; Wang, Qiang; Xiong, Lize

    2015-01-01

    Recent studies have demonstrated that adiponectin (APN) attenuates cerebral ischemic/reperfusion via globular adiponectin (gAD). However, the therapeutic role of gAD in cerebral ischemic injury in type 1 diabetes mellitus (T1DM) remains unclear. Our results showed that gAD improved neurological scores and reduced the infarct volumes in the 8-week T1DM (T1DM-8W) mice, but not in the 2-week T1DM (T1DM-2W) mice. Moreover, the ischemic penumbra APN levels increased and peaked in T1DM-2W mice, and reduced to normal in T1DM-8W mice, while the APN receptor 1 (AdipoR1) expression change was the opposite. Administration of rosiglitazone in T1DM-2W mice up-regulated the expression of AdipoR1 and restored the neuroprotection of gAD, while intracerebroventricular injection of AdipoR1 small interfering RNA (siRNA) in T1DM-8W mice reversed it. Furthermore, the expression of p-PERK, p-IRE1 and GRP78 were increased whereas the expressions of CHOP and cleaved caspase-12 as well as the number of apoptotic neurons were decreased after gAD treatment in T1DM-8W mice. These beneficial effects of gAD were reversed by pretreatment with AdipoR1 siRNA. These results demonstrated a dynamic dysfunction of APN/AdipoR1 accompanying T1DM progression. Interventions bolstering AdipoR1 expression during early stages and gAD supplementation during advanced stages may potentially reduce the cerebral ischemic injury in diabetic patients. PMID:26611106

  10. Dieckol isolated from Ecklonia cava inhibits alpha-glucosidase and alpha-amylase in vitro and alleviates postprandial hyperglycemia in streptozotocin-induced diabetic mice.

    PubMed

    Lee, Seung-Hong; Park, Mi-Hwa; Heo, Soo-Jin; Kang, Sung-Myung; Ko, Seok-Chun; Han, Ji-Sook; Jeon, You-Jin

    2010-10-01

    This study was designed to investigate whether dieckol may inhibit ?-glucosidase and alpha-amylase activities, and alleviate postprandial hyperglycemia in streptozotocin-induced diabetic mice. Dieckol isolated from Ecklonia cava, brown algae, evidenced prominent inhibitory effect against alpha-glucosidase and alpha-amylase. The IC(50) values of dieckol against alpha-glucosidase and alpha-amylase were 0.24 and 0.66 mM, respectively, which evidenced the higher activities than that of acarbose. Dieckol did not exert any cytotoxic effect in human umbilical vein endothelial cells (HUVECs) at various concentrations (from 0.33 to 2.69 mM). The increase of postprandial blood glucose levels were significantly suppressed in the dieckol administered group than those in the streptozotocin-induced diabetic or normal mice. Moreover, the area under curve (AUC) was significantly reduced via dieckol administration (259 versus 483 mmol min/l) in the diabetic mice as well as it delays absorption of dietary carbohydrates. Therefore, these result indicated that dieckol might be a potent inhibitor for ?-glucosidase and ?-amylase. PMID:20600532

  11. Csf2 and Ptgs2 Epigenetic Dysregulation in Diabetes-prone Bicongenic B6.NODC11bxC1tb Mice

    PubMed Central

    Garrigan, Erin; Belkin, Nicole S.; Seydel, Federica; Han, Zhao; Carter, Jamal; McDuffie, Marcia; Morel, Laurence; Peck, Ammon B.; Clare-Salzler, Michael J.; Atkinson, Mark; Wasserfall, Clive; Davoodi-Semiromi, Abdoreza; Shi, Jing-da; Haskell-Luevano, Carrie; Yang, Li-Jun; Alexander, John J.; Cdebaca, Autumn; Piliant, Teresa; Riggs, Corin; Amick, Matthew; Litherland, Sally A.

    2015-01-01

    In Type 1 diabetic (T1D) human monocytes, STAT5 aberrantly binds to epigenetic regulatory sites of two proinflammatory genes, CSF2 (encoding granulocyte–macrophage colony-stimulating factor) and PTGS2 (encoding prostaglandin synthase 2/cyclooxygenase 2). Bicongenic B6.NOD C11bxC1tb mice re-create this phenotype of T1D monocytes with only two nonobese diabetic (NOD) Idd subloci (130.8 Mb–149.7 Mb, of Idd5 on Chr 1 and 32.08–53.85 Mb of Idd4.3 on Chr11) on C57BL/6 genetic background. These two Idd loci interact through STAT5 binding at upstream regulatory regions affecting Csf2 (Chr 11) and Ptgs2 (Chr 1) expression. B6.NODC11bxC1tb mice exhibited hyperglycemia and immune destruction of pancreatic islets between 8 and 30 weeks of age, with 12%–22% penetrance. Thus, B6.NODC11bxC1tb mice embody NOD epigenetic dysregulation of gene expression in myeloid cells, and this defect appears to be sufficient to impart genetic susceptibility to diabetes in an otherwise genetically nonautoimmune mouse. PMID:26512207

  12. Dietary wolfberry up-regulates carotenoid metabolic genes and enhances mitochondrial biogenesis in the retina of db/db diabetic mice

    PubMed Central

    Yu, Huifeng; Wark, Logan; Ji, Hua; Willard, Lloyd; Jaing, Yu; Han, Jing; He, Hui; Ortiz, Edlin; Zhang, Yunong; Medeiros, Denis M; Lin, Dingbo

    2013-01-01

    Scope Our aim was to investigate whether dietary wolfberry altered carotenoid metabolic gene expression and enhanced mitochondrial biogenesis in the retina of diabetic mice. Methods and Results Six-week-old male db/db and wild type mice were fed the control or wolfberry diets for 8 weeks. At study termination, liver and retinal tissues were collected for analysis by transmission electron microscopy, real-time PCR, immunoprecipitation, Western blot, and HPLC. Wolfberry elevated zeaxanthin and lutein levels in the liver and retinal tissues and stimulated expression of retinal scavenger receptor class B type I, glutathione S-transferase Pi 1, and ?,?-carotene 9’,10’-oxygenase 2, and induced activation and nuclear enrichment of retinal AMP-activated protein kinase ?2 (AMPK?2). Furthermore, wolfberry attenuated hypoxia and mitochondrial stress as demonstrated by declined expression of hypoxia-inducible factor-1?, vascular endothelial growth factor, and heat shock protein 60. Wolfberry enhanced retinal mitochondrial biogenesis in diabetic retinas as demonstrated by reversed mitochondrial dispersion in the retinal pigment epithelium, increased mitochondrial copy number, elevated citrate synthase activity, and up-regulated expression of peroxisome proliferator-activated receptor ? co-activator 1 ?, nuclear respiratory factor 1, and mitochondrial transcription factor A. Conclusion Consumption of dietary wolfberry could be beneficial to retinoprotection through reversal of mitochondrial function in diabetic mice. PMID:23505020

  13. Chronic administration of palmitoleic acid reduces insulin resistance and hepatic lipid accumulation in KK-Ay Mice with genetic type 2 diabetes

    PubMed Central

    2011-01-01

    Background Studies have demonstrated the beneficial effect of palmitoleic acid (C16:1 n-7) on reducing muscle insulin resistance and preventing beta-cell apoptosis. However, the effect of palmitoleic acid on diabetes remains to be elucidated. The aim of this study was to examine the antidiabetic effect of palmitoleic acid in KK-Ay mice, a spontaneous model for studies of obese type 2 diabetes with low insulin sensitivity. Methods KK-Ay mice were orally administered vehicle, 300 mg/kg of palmitoleic acid, or 300 mg/kg of palmitic acid (C16:0) on a daily basis for 4 weeks. Results Palmitoleic acid reduced body weight increase, ameliorated the development of hyperglycemia and hypertriglyceridemia, and improved insulin sensitivity. In addition, hepatic characteristics were significantly affected, as weight of the liver and hepatic triglyceride levels were lower in the palmitoleic acid group when compared to the control (vehicle and palmitic acid groups). Oil red O staining clearly indicated reduced hepatic lipid accumulation in response to palmitoleic acid. Furthermore, palmitoleic acid down-regulated mRNA expressions of proinflammatory adipocytokine genes (TNF? and resistin) in white adipose tissue and lipogenic genes (SREBP-1, FAS, and SCD-1) in liver. Conclusions These results suggest that palmitoleic acid improves hyperglycemia and hypertriglyceridemia by increasing insulin sensitivity, in part owing to suppressing proinflammatory gene expressions and improving hepatic lipid metabolism in diabetic mice. PMID:21774832

  14. Short-Term Feeding of Fibre-Enriched Biscuits: Protective Effect against Hepatotoxicity in Diabetic Rats

    PubMed Central

    Erukainure, Ochuko L.; Ebuehi, Osaretin A. T.; Adeboyejo, Folasade O.; Oladunmoye, Olufunmilola O.; Obode, Okukwe C.; Olasehinde, Tosin; Elemo, Gloria N.

    2015-01-01

    The effects of fibre-enriched biscuit on biomarkers associated with hepatotoxicity in diabetic rats were investigated. Diabetes was induced by single intraperitoneal injection of alloxan monohydrate. Treatment lasted for 14 days after which the rats were sacrificed by cervical dislocation. Blood serum was analyzed to determine hepatic function enzymes. The liver was also analyzed to determine hepatic lipid profile and antioxidant enzymes. Induction of diabetes led to elevated levels of ALP, AST, and ALT. These were, however, significantly (p < 0.05) reduced in the fibre-enriched biscuit fed (treated) group. There was no significant difference in the serum bilirubin and total protein levels of the studied groups. Reduced albumin level was observed in the diabetic group; this was further lowered on feeding with fibre-enriched biscuits. Induction of diabetes led to increased hepatic level of cholesterol, triglyceride (TG), low density lipoprotein (LDL), and lipid peroxidation and decreased activities of glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD) and HDL level. These were significantly (p < 0.05) reversed on feeding with fibre-enriched biscuit. This study portrays the protective effect of fibre-enriched biscuit on increased oxidative stress and hyperlipidemia in hepatic tissues of alloxan-induced diabetic rats. PMID:26713163

  15. Cyanidin-3-Glucoside-Rich Extract from Chinese Bayberry Fruit Protects Pancreatic ? Cells and Ameliorates Hyperglycemia in Streptozotocin-Induced Diabetic Mice

    PubMed Central

    Sun, Chong-De; Zhang, Bo; Zhang, Jiu-Kai; Xu, Chang-Jie; Wu, Yu-Lian; Chen, Kun-Song

    2012-01-01

    Abstract Chinese bayberry fruit is a rich source of anthocyanins, especially cyanidin-3-glucoside (C3G). The present study investigated the protective effects of C3G-rich bayberry fruit extract (CRBFE) against pancreatic ? cells against oxidative stress–induced injury as well as its hypoglycemic effect in diabetic mice. Bayberry extract from “Biqi” was used for both in vitro and in vivo testing because of its high C3G content and high antioxidant capacity. Pretreatment of ? cells with CRBFE (containing 0.5??mol/L C3G) prevented cell death, increased cellular viability, and decreased mitochondrial reactive oxygen species production and cell necrosis induced by 800 or 1,200??mol/L H2O2. CRBFE dose-dependently up-regulated pancreatic duodenal homeobox 1 gene expression, contributing to increased insulin-like growth factor II gene transcript levels and insulin protein in INS-1 cells. In addition, administration of CRBFE (150??g of C3G/10?g of body weight twice per day) significantly reduced blood glucose in streptozotocin-induced diabetic ICR mice and increased the glucose tolerance in an oral glucose tolerance test (P<.05). Such results indicated that CRBFE might be useful in prevention and control of diabetes mellitus and diabetes-associated complications. PMID:22181073

  16. Effects of Hydro-alcoholic Extract from Arctium lappa L. (Burdock) Root on Gonadotropins, Testosterone, and Sperm Count and Viability in Male Mice with Nicotinamide/ Streptozotocin-Induced Type 2 Diabetes

    PubMed Central

    AHANGARPOUR, Akram; OROOJAN, Ali Akbar; HEIDARI, Hamid; GHAEDI, Ehsan; TAHERKHANI, Reza

    2015-01-01

    Background: Reproductive dysfunction is a complication of diabetes. Arctium lappa (burdock) root has hypoglycemic and antioxidative properties, which are traditionally used for treatment of impotence and sterility. Therefore, the aim of this study is to investigate the effects of its hydro alcoholic extract on gonadotropin, testosterone, and sperm parameters in nicotinamide/ streptozotocin-induced diabetic mice. Methods: In this experimental study, 56 adult male Naval Medical Research Institute (NMRI) mice (30–35 g) were randomly divided into seven groups: control, diabetes, diabetes + glibenclamide (0.25 mg/kg), diabetes + extract (200 or 300 mg/kg), and extract (200 or 300 mg/kg). Diabetes was induced with intraperitoneal injection of nicotinamide (NA) and streptozotocin (STZ). Twenty-four hours after the last extract and drug administration, serum samples, testes, and cauda epididymis were removed immediately for experimental assessment. Results: Body weight, serum luteinizing hormone (LH), follicle stimulating hormone (FSH), and testosterone levels, and sperm count (P < 0.05) and viability (P < 0.01) decreased in diabetic mice. Administration of glibenclamide significantly improved these reductions in diabetic animals (P < 0.05). However, the hydro alcoholic extract (300 mg/kg) enhanced sperm viability only in diabetic mice (P < 0.01). In addition, this dose of extract increased sperm count, LH, FSH, and testosterone in nondiabetic animals compared with the control group (P < 0.05). Conclusion: The results indicate that applied burdock root extract has anti-infertility effects in nondiabetic mice. Hence, this part of the A. lappa plant has an effect on the health of the reproductive system in order to improve diabetic conditions. PMID:26023292

  17. Early initiation of low-level parenteral dextrose induces an accelerated diabetic phenotype in septic C57BL/6J mice.

    PubMed

    Singamsetty, Srikanth; Shah, Faraaz Ali; Guo, Lanping; Watanabe, Yoshio; McDonald, Sherie; Sharma, Rohit; Zhang, Yingze; Alonso, Laura C; O'Donnell, Christopher P; McVerry, Bryan J

    2016-01-01

    Development of hyperglycemia during sepsis is associated with increased morbidity and mortality. Nutritional support is common practice in the intensive care unit, but the metabolic effects are not well understood. The purpose of this study is to determine the effect of early low-level calorie provision on the development of hyperglycemia in a clinically relevant murine model of sepsis. C57BL/6J mice underwent femoral arterial and venous catheterization followed by cecal ligation and puncture (CLP) or sham surgery and low-dose intravenous dextrose or saline infusion. Blood glucose, plasma insulin, and cytokines were measured after 24 h. Additional septic mice underwent hyperinsulinemic-euglycemic clamps or received intravenous insulin concurrent with dextrose to determine whole-body insulin sensitivity and test the efficacy of insulin to reverse hyperglycemia. Neither dextrose infusion nor CLP alone induced hyperglycemia. Early initiation of low-l