Science.gov

Sample records for stz-induced diabetic rats

  1. Attenuated Effects of Deep-Sea Water on Hepatic Apoptosis in STZ-Induced Diabetic Rats.

    PubMed

    Hsu, Tsai-Ching; Chiu, Chun-Ching; Lin, Hsou-Lin; Kao, Tseng-Wei; Chen, Li-Jeng; Wu, Li-Yi; Huang, Chih-Yang; Tzang, Bor-Show

    2015-06-30

    Diabetes mellitus (DM) is a metabolic disorder and increasing evidences have indicated a connection between DM and hepatic abnormality. Deep-sea water (DSW) has been applied in many fields, especially in medicine; herein, we investigated the influence of DSW on hepatic apoptosis in streptozocin (STZ)-induced diabetes rats. Our experimental results firstly demonstrated the beneficial effects of 1×DSW, 2×DSW and 3×DSW in alleviating hepatic apoptosis in STZ-induced diabetic rats. We demonstrated that 1×DSW, 2×DSW and 3×DSW significantly suppressed the caspase-3 activity and TUNEL-positive cells in livers of STZ-induced diabetic rats. Significant reductions of both Fas-dependent and mitochondrial-dependent apoptotic molecules were also detected in livers of STZ-induced diabetic rats receiving DSW. Additionally, apoptotic signaling molecules such as phosphorylated IκB-α and NF-κB were significantly reduced in livers of DSW-treated STZ-induced diabetic rats. These findings indicate hepatic protective effects of DSW on DM and suggest DSW as a possible ingredient for health food. PMID:26014125

  2. Fenugreek Prevents the Development of STZ-Induced Diabetic Nephropathy in a Rat Model of Diabetes

    PubMed Central

    Jin, Yingli; Shi, Yan; Zou, Yinggang; Miao, Chunsheng; Sun, Bo; Li, Cai

    2014-01-01

    The present study aims to examine the protective effect of fenugreek and the underlying mechanism against the development of diabetic nephropathy (DN) in streptozotocin- (STZ-) induced diabetic rats. A rat model of diabetes was successfully established by direct injection of STZ and then the rats were administered an interventional treatment of fenugreek. Parameters of renal function, including blood glucose, albuminuria, hemoglobin A1c (HbA1c), dimethyl formamide (DMF), blood urine nitrogen (BUN), serum creatinine (Scr), and kidney index (KI), were detected in the three groups (Con, DN, and DF). Oxidative stress was determined by the activity of antioxidase. Extracellular matrix (ECM) accumulation and other morphological alterations were evaluated by means of immunohistochemistry and electron microscope. Quantitive (q)PCR was employed to detect the mRNA expression of transforming growth factor-?1 (TGF-?1) and connective tissue growth factor (CTGF) and protein expression was determined with western blot analysis. DN rats in the present study demonstrated a significant renal dysfunction, ECM accumulation, pathological alteration, and oxidative stress, while the symptoms were evidently reduced by fenugreek treatment. Furthermore, the upregulation of TGF-?1 and CTGF at a transcriptional and translational level in DN rats was distinctly inhibited by fenugreek. Consequently, fenugreek prevents DN development in a STZ-induced diabetic rat model. PMID:25057273

  3. Protective Effect of Agaricus brasiliensis on STZ-Induced Diabetic Neuropathic Pain in Rats.

    PubMed

    Ji, Weifeng; Huang, Haiying; Chao, Ji; Lu, Wuchao; Guo, Jianyou

    2014-01-01

    Objective. The present investigation examined the neuroprotective effect of Agaricus brasiliensis (AbS) against STZ-induced diabetic neuropathic pain in laboratory rats. STZ-induced diabetic rats were administered orally with AbS. Body weight, serum glucose, and behavioral parameters were measured before and at the end of the experiment to see the effect of AbS on these parameters. After 6 weeks of treatments, all animals were sacrificed to study various biochemical parameters. Treatment with AbS 80?mg/kg in diabetic animals showed significant increase in body weight, pain threshold, and paw withdrawal threshold and significant decrease in serum glucose, LPO and NO level, Na-K-ATPase level, and TNF- ? and IL-1 ? level as compared to vehicle treated diabetic animals in dose and time dependent manner. AbS can offer pain relief in PDN. This may be of potential benefit in clinical practice for the management of diabetic neuropathy. PMID:24527050

  4. Ameliorative potential of S-allyl cysteine on oxidative stress in STZ induced diabetic rats.

    PubMed

    Saravanan, Ganapathy; Ponmurugan, Ponnusamy

    2011-01-15

    Increased oxidative stress and impaired antioxidant defense mechanism are important factors in the pathogenesis and progression of diabetes mellitus and other oxidant-related diseases. The present study was undertaken to evaluate the possible protective effects of S-allyl cysteine (SAC) against oxidative stress in streptozotocin (STZ) induced diabetic rats. SAC was administered orally for 45 days to control and STZ induced diabetic rats. The effects of SAC on glucose, plasma insulin, thiobarbituric acid reactive substances (TBARS), hydroperoxide, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH), oxidized glutathione (GSSG) and GSH/GSSG ratio were studied. The levels of glucose, TBARS, hydroperoxide, and GSSG were increased significantly whereas the levels of plasma insulin, reduced glutathione, GSH/GSSG ratio, superoxide dismutase, catalase and GPx were decreased in STZ induced diabetic rats. Administration of SAC to diabetic rats showed a decrease in plasma glucose, TBARS, hydroperoxide and GSSG. In addition, the levels of plasma insulin, superoxide dismutase, catalase, GPx and reduced glutathione (GSH) were increased in SAC treated diabetic rats. The above findings were supported by histological observations of the liver and kidney. The antioxidant effect of SAC was compared with glyclazide, a well-known antioxidant and antihyperglycemic drug. The present study indicates that the SAC possesses a significant favorable effect on antioxidant defense system in addition to its antidiabetic effect. PMID:20951120

  5. Effect of arctiin on glomerular filtration barrier damage in STZ-induced diabetic nephropathy rats.

    PubMed

    Ma, Song-Tao; Liu, Dong-lian; Deng, Jing-jing; Niu, Rui; Liu, Rui-bin

    2013-10-01

    Diabetic nephropathy (DN) is the major life-threatening complication of diabetes. Abnormal permeability of glomerular basement membrane plays an important role in DN pathogenesis. This study was performed to assess the effect of arctiin, the lignan constituent from Arctium lappa L., on metabolic profile and aggravation of renal lesions in a rat model of streptozotocin (STZ)-induced DN. STZ-induced diabetic rats were treated with arctiin at the dosage of 60 or 40 mg/kg/day via intraperitoneal injection for 8 weeks. Blood glucose and 24-h urinary albumin content were measured, and kidney histopathological changes were monitored. RT-PCR and immunohistochemistry were used to detect the mRNA and protein levels of nephrin, podocin and heparanase (HPSE) in the kidney cortex of rats, respectively. Treatment with arctiin significantly decreased the levels of 24-h urinary albumin, prevented the sclerosis of glomeruli and effectively restored the glomerular filtration barrier damage by up-regulating the expression of nephrin and podocin and down-regulating HPSE level. Our studies suggest that arctiin might be beneficial for DN. The effects of arctiin on attenuating albuminuria and glomerulosclerosis are possibly mediated by regulating the expression of nephrin and podocin and HPSE in STZ-induced diabetic rats. PMID:23147865

  6. Biomechanical and histomorphometric colon remodelling in STZ-induced diabetic rats.

    PubMed

    Zhao, Jingbo; Nakaguchi, Toshiya; Gregersen, Hans

    2009-08-01

    The histomorphologic and passive biomechanical properties were studied in the mid-colon of 16 non-diabetic and 20 streptozotocin (STZ)-induced diabetic rats (50 mg/kg STZ, ip). The diabetic rats were divided into groups living 4 and 8 weeks after the induction of diabetes (n = 10 for each group). The mechanical test was a ramp distension of fluid into the colon in vitro. The colon diameter and length were obtained from digitized images of the segments at pre-selected pressures and at the no-load and zero-stress states. Circumferential and longitudinal stresses and strains were computed from the length, diameter, and pressure data and from the zero-stress state geometry. The blood glucose level increased 3-4-fold in the diabetic rats compared with the controls (P < 0.001). Diabetes generated pronounced increases in the colon weight per length, wall thickness, and wall cross-sectional area (P < 0.001). Histologically, the thickness of all layers was increased during diabetes (P < 0.05), especially the mucosa layer. The opening angle, and absolute values of residual strain increased in the diabetic group (P < 0.05 and P < 0.01, respectively). Furthermore, diabetes increased the circumferential and longitudinal stiffness of the colon wall (P < 0.001). The observed changes in residual strain, opening angle, and stress-strain relation may be contributing factors to colonic dysfunction and abdominal pain in diabetic patients. PMID:18989775

  7. RNA sequencing reveals retinal transcriptome changes in STZ-induced diabetic rats

    PubMed Central

    LIU, YUAN-JIE; LIAN, ZHI-YUN; LIU, GENG; ZHOU, HONG-YING; YANG, HUI-JUN

    2016-01-01

    The present study aimed to investigate changes in retinal gene expression in streptozotocin (STZ)-induced diabetic rats using next-generation sequencing, utilize transcriptome signatures to investigate the molecular mechanisms of diabetic retinopathy (DR), and identify novel strategies for the treatment of DR. Diabetes was chemically induced in 10-week-old male Sprague-Dawley rats using STZ. Flash-electroretinography (F-ERG) was performed to evaluate the visual function of the rats. The retinas of the rats were removed to perform high throughput RNA sequence (RNA-seq) analysis. The a-wave, b-wave, oscillatory potential 1 (OP1), OP2 and ∑OP amplitudes were significantly reduced in the diabetic group, compared with those of the control group (P<0.05). Furthermore, the implicit b-wave duration 16 weeks post-STZ induction were significantly longer in the diabetic rats, compared with the control rats (P<0.001). A total of 868 genes were identified, of which 565 were upregulated and 303 were downregulated. Among the differentially expressed genes (DEGs), 94 apoptotic genes and apoptosis regulatory genes, and 19 inflammatory genes were detected. The results of the KEGG pathway significant enrichment analysis revealed enrichment in cell adhesion molecules, complement and coagulation cascades, and antigen processing and presentation. Diabetes alters several transcripts in the retina, and RNA-seq provides novel insights into the molecular mechanisms underlying DR. PMID:26781437

  8. Effect of Rebaudioside A, a diterpenoid on glucose homeostasis in STZ-induced diabetic rats.

    PubMed

    Saravanan, Ramalingam; Vengatash babu, Kaliyappan; Ramachandran, Vinayagam

    2012-09-01

    Rebaudioside A (Reb A), a major constituent of Stevia rebaudiana, was recently proposed as an insulinotropic agent. The aim of this investigation was to evaluate the antihyperglycemic effect of Reb A on the activities of hepatic enzymes of carbohydrate metabolism in streptozotocin (STZ)-induced diabetic rats. Diabetes was induced in adult male Albino Wistar rats, weighing 180-200 g, by a single intraperitoneal injection at a dose of STZ (40 mg/kg body weight). Diabetic rats showed significant (P<0.05) increase in the levels of plasma glucose and glycosylated hemoglobin and significant (P<0.05) decrease in the levels of plasma insulin and hemoglobin. Activities of gluconeogenic enzymes such as glucose-6-phosphatase and fructose-1,6-bisphosphatase were significantly (P<0.05) increased while hexokinase and glucose-6-phosphate dehydrogenase were significantly (P<0.05) decreased in the liver along with glycogen. Oral treatment with Reb A to diabetic rats significantly (P<0.05) decreased blood glucose and reversed these hepatic carbohydrate metabolizing enzymes in a significant manner. Histopathology changes of pancreas confirmed the protective effects of Reb A in diabetic rats. Thus, the results show that Reb A possesses an antihyperglycemic activity and provide evidence for its traditional usage in the control of diabetes. PMID:22374587

  9. Puerarin Improves Diabetic Aorta Injury by Inhibiting NADPH Oxidase-Derived Oxidative Stress in STZ-Induced Diabetic Rats

    PubMed Central

    Li, Wenping; Zhao, Wenwen; Wu, Qin; Lu, Yuanfu; Shi, Jingshan; Chen, Xiuping

    2016-01-01

    Objective. Puerarin is a natural flavonoid isolated from the TCM lobed kudzuvine root. This study investigated the effect and mechanisms of puerarin on diabetic aorta in rats. Methods. Streptozotocin- (STZ-) induced diabetic rats were administered with puerarin for 3 weeks. Levels of serum insulin (INS), PGE2, endothelin (ET), glycated hemoglobin (GHb), H2O2, and nitric oxide (NO) in rats were measured by ELISA and colorimetric assay kits. The aortas were stained with H&E. Moreover, the mRNA expression of ICAM-1, LOX-1, NADPH oxidase 2 (NOX2), and NOX4 and the protein expression of ICAM-1, LOX-1, NF-κB p65, E-selectin, NOX2, and NOX4 in aorta tissues were measured by real-time PCR and Western blot, respectively. The localization of ICAM-1, NF-κB p65, NOX2, and NOX4 in the aorta tissues was also determined through immunohistochemistry. Results. Puerarin treatment exerted no effect on fasting blood glucose levels but significantly reduced the serum levels of INS, GHb, PGE2, ET, H2O2, and NO. In addition, puerarin improved the pathological alterations and inhibited the expression of ICAM-1, LOX-1, NOX2, and NOX4 at both mRNA and protein levels. Puerarin also significantly reduced the number of cells showing positive staining for ICAM-1, NOX2, NOX4, and NF-κB p65. Conclusion. Puerarin demonstrated protective effect on the STZ-induced diabetic rat aorta. The protective mechanisms may include regulation of NF-κB and inhibition of NOX2 and NOX4 followed by inhibition of cell adhesion molecule expression. PMID:26881260

  10. The inhibitory effect of Isoflavones isolated from Caesalpinia pulcherrima on aldose reductase in STZ induced diabetic rats.

    PubMed

    Kumar, Munipally Praveen; Sankeshi, Venu; Naik, R Ravindar; Thirupathi, P; Das, Biswanath; Raju, T N

    2015-07-25

    Increased aldose reductase activity has been implicated in the development of retinopathy due to accumulation of intracellular sugar alcohol, i.e., sorbitol. In this study, the compounds isolated from the Caesalpinia pulcherrima, have been examined for its inhibitory effects on aldose reductase (AR), which plays a major role in diabetic retinopathy. 3,6,7,4',5'-Pentamethoxy-5,3'-dihydroxyflavone (Compound 2) has shown significant inhibition of rat retina AR with an IC50 value of 16.24±0.046μM in a non-competitive manner. Molecular docking study results are steady with the pattern of AR inhibition by Compound 2 and its specificity. The supplementation of Compound 2 suppresses sorbitol accumulation in retina by decreased AR activity in STZ induced diabetic rat in dose dependent manner. Besides this, rats fed with Compound 2 have shown improved levels of antioxidant enzymes. This study revealed that Compound 2 has pharmacologically active component with a potential to inhibit rat retina AR and affecting the delaying process of diabetic retinopathy in STZ induced diabetic rats. PMID:25986969

  11. Efficacy of natural diosgenin on cardiovascular risk, insulin secretion, and beta cells in streptozotocin (STZ)-induced diabetic rats.

    PubMed

    Kalailingam, Pazhanichamy; Kannaian, Bhuvaneswari; Tamilmani, Eevera; Kaliaperumal, Rajendran

    2014-09-15

    Costus igneus, has been prescribed for the treatment of diabetic mellitus in India for several years. The aim of this study is to investigate the effects of plant derived diosgenin on cardiovascular risk, insulin secretion, and pancreatic composition through electron microscopical studies of normal and diabetic rats. Diosgenin at a dose of 5 or 10mg/kg per body weight (bw) was orally administered as a single dose per day to diabetic induced rats for a period of 30 days. The effect of diosgenin on blood glucose, HbA1c, PT, APTT, Oxy-LDL, serum lipid profile, electron microscopical studies of pancreas, antioxidant enzymes (in liver, kidney, pancreas) and hepatoprotective enzymes in plasma and liver were measured in normal and diabetic rats. The results showed that fasting blood glucose, PT, APTT, Oxy-LDL, TC, TG, LDL, ALT, AST, ALP, glucose-6-phosphatase, fructose-1,6-bisphosphatase and LPO levels were significantly (p<0.05) increased, whereas HDL, SOD, CAT, GSH and the glycolytic enzyme glucokinase levels were significantly (p<0.05) decreased in the diabetes induced rats and these levels were significantly (p<0.05) reversed back to normal in diabetes induced rats after 30 days of treatment with diosgenin. Electron microscopical studies of the pancreas revealed that the number of beta cells and insulin granules were increased in streptozotocin (STZ) induced diabetic rats after 30 days of treatment with diosgenin. In conclusion, the data obtained from the present study strongly indicate that diosgenin has potential effects on cardiovascular risk, insulin secretion and beta cell regeneration in STZ induced diabetic rats, these results could be useful for new drug development to fight diabetes and its related cardiovascular diseases. PMID:24889525

  12. The effects of hydroalcoholic extract of Nigella sativa seed on oxidative stress in hippocampus of STZ-induced diabetic rats

    PubMed Central

    Abbasnezhad, Abbasali; Hayatdavoudi, Parichehr; Niazmand, Saeed; Mahmoudabady, Maryam

    2015-01-01

    Objective: Oxidative stress plays an important role in the etiology of diabetic complications. Diabetes impairs hippocampus neurogenesis, synaptic plasticity, and learning. The aim of this study was to investigate the effects of hydroalcoholic extract of Nigella sativa seed on oxidative stress in STZ-induced diabetic rats' hippocampus. Materials and Methods: Diabetes induced by 60 mg/kg STZ, i.p, and the rats were divided into five experimental groups (n=8-10 in each group) including control (received 0.5 ml normal saline), untreated STZ-diabetic (received 0.5 ml normal saline), and treated rats received Nigella sativa extract (200 and 400 mg/kg) or metformin (300 mg/kg) by gavage for 42 days. Serum glucose concentration and body weight as well as hippocampus tissue malondialdehyde and thiol levels were determined by calorimetric assay. Results: Serum glucose level in the diabetic rats treated with 200 mg/kg Nigella sativa extract at the days 24 and 45 decreased in comparison to untreated diabetic group (p<0.05, p<0.01, respectively). Weight loss was significantly different between metformin and Nigella sativa extract at the dose of 200 and 400 mg/kg (p<0.05). Thiol content of hippocampus increased by 200 mg/kg Nigella sativa extract in comparison to untreated diabetic group (p<0.05). Malondialdehyde content of hippocampus reduced by Nigella sativa extract, 200 mg/kg (p<0.001), 400 mg/kg (p<0.05), and metformin (p<0.05) in comparison to the untreated diabetic group. Conclusion: The results of the present study showed that hydroalcoholic extract of the Nigella sativa decreased oxidative stress in hippocampus of the STZ-induced diabetic rats. Nigella sativa at the dose of 200 mg/kg was more effective to reduce oxidative stress in hippocampus of rats. PMID:26445713

  13. Garlic Oil Alleviates MAPKs- and IL-6-mediated Diabetes-related Cardiac Hypertrophy in STZ-induced DM Rats

    PubMed Central

    Chang, Sheng-Huang; Liu, Chung-Jung; Kuo, Chia-Hua; Chen, Hong; Lin, Wen-Yuan; Teng, Kun-Yu; Chang, Sheng-Wei; Tsai, Chang-Hai; Tsai, Fuu-Jen; Huang, Chih-Yang; Tzang, Bor-Show; Kuo, Wei-Wen

    2011-01-01

    Garlic oil has been reported to protect the cardiovascular system; however, the effects and mechanisms behind the cardioprotection of garlic oil on diabetes-induced cardiaomyopathy are unclear. In this study, we used streptozotocin (STZ)-induced diabetic rats to investigate whether garlic oil could protect the heart from diabetes-induced cardiomyopathy. Wistar STZ-induced diabetic rats received garlic oil (0, 10, 50 or 100?mg?kg_1 body weight) by gastric gavage every 2 days for 16 days. Normal rats without diabetes were used as control. Cardiac contractile dysfunction and cardiac pathologic hypertrophy responses were observed in diabetic rat hearts. Cardiac function was examined using echocardiography. In addition to cardiac hypertrophy-related mitogen-activated protein kinases (MAPK) pathways (e.g., p38, c-Jun N-terminal kinases (JNK) and extracellularly responsive kinase (ERK1/2)), the IL-6/MEK5/ERK5 signaling pathway was greatly activated in the diabetic rat hearts, which contributes to the up-regulation of cardiac pathologic hypertrophy markers including atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP), and leads to cardiac contractile dysfunction. Garlic oil treatment significantly inhibited the up-regulation in MAPK (e.g., p38, JNK and ERK1/2) and IL-6/MEK5/ERK5 signaling pathways in the diabetic rat hearts, reducing the levels of cardiac pathologic hypertrophy markers such as ANP and BNP, and improving the cardiac contractile function. Collectively, data from these studies demonstrate that garlic oil shows the potential cardioprotective effects for protecting heart from diabetic cardiomyopathy. PMID:21792366

  14. Garlic Oil Alleviates MAPKs- and IL-6-mediated Diabetes-related Cardiac Hypertrophy in STZ-induced DM Rats.

    PubMed

    Chang, Sheng-Huang; Liu, Chung-Jung; Kuo, Chia-Hua; Chen, Hong; Lin, Wen-Yuan; Teng, Kun-Yu; Chang, Sheng-Wei; Tsai, Chang-Hai; Tsai, Fuu-Jen; Huang, Chih-Yang; Tzang, Bor-Show; Kuo, Wei-Wen

    2011-01-01

    Garlic oil has been reported to protect the cardiovascular system; however, the effects and mechanisms behind the cardioprotection of garlic oil on diabetes-induced cardiaomyopathy are unclear. In this study, we used streptozotocin (STZ)-induced diabetic rats to investigate whether garlic oil could protect the heart from diabetes-induced cardiomyopathy. Wistar STZ-induced diabetic rats received garlic oil (0, 10, 50 or 100?mg?kg(_1) body weight) by gastric gavage every 2 days for 16 days. Normal rats without diabetes were used as control. Cardiac contractile dysfunction and cardiac pathologic hypertrophy responses were observed in diabetic rat hearts. Cardiac function was examined using echocardiography. In addition to cardiac hypertrophy-related mitogen-activated protein kinases (MAPK) pathways (e.g., p38, c-Jun N-terminal kinases (JNK) and extracellularly responsive kinase (ERK1/2)), the IL-6/MEK5/ERK5 signaling pathway was greatly activated in the diabetic rat hearts, which contributes to the up-regulation of cardiac pathologic hypertrophy markers including atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP), and leads to cardiac contractile dysfunction. Garlic oil treatment significantly inhibited the up-regulation in MAPK (e.g., p38, JNK and ERK1/2) and IL-6/MEK5/ERK5 signaling pathways in the diabetic rat hearts, reducing the levels of cardiac pathologic hypertrophy markers such as ANP and BNP, and improving the cardiac contractile function. Collectively, data from these studies demonstrate that garlic oil shows the potential cardioprotective effects for protecting heart from diabetic cardiomyopathy. PMID:21792366

  15. Anti-diabetic and antihyperlipidemic effect of allopolyherbal formulation in OGTT and STZ-induced diabetic rat model.

    PubMed

    Manik, Swati; Gauttam, Vinod; Kalia, A N

    2013-09-01

    The present study was undertaken to evaluate the antidiabetic and antihyperlipidemic activities of Allopolyherbal formulation (APHF) consisting of combinations of three well known medicinal plants used in traditional medicines (Trigonella foenum graceum, Momordica charantia, Aegle marmelos) and synthetic oral hypoglycaemic drug (Glipizide-GL). The optimized combination of lyophilized hydro-alcoholic extracts of drugs was 2:2:1 using OGTT model. The optimized PHF was simultaneously administered with GL and optimized using OGTT model in diabetic rats and further studied in STZ-induced diabetic rats for 21 days. The results (serum glucose level, lipid profile, hepatic enzymes and body weight) were compared with the standard drug GL (10 mg/kg body wt). The optimized APHF (500+5 mg/kg body wt) has shown significant antihyperglycemic and antihyperlipidemic activities. The results were comparable with the standard; even better than the GL (10 mg/kg body wt) alone. The proposed hypothesis has reduced the no. of drug components from eight to three and dose almost 50% of both PHF and GL which fulfil the FDA requirements for export. Thus the developed APHF will be an ideal alternative for the existing hypoglycemic formulations in the market with an additional advantage of hypolipidemic effect and minimizing the cardiovascular risk factors associated with diabetes. PMID:24377129

  16. The effect of Stevia rebaudiana on serum omentin and visfatin level in STZ-induced diabetic rats.

    PubMed

    Akbarzadeh, Samad; Eskandari, Fatemeh; Tangestani, Hadis; Bagherinejad, Somaieh Tangerami; Bargahi, Afshar; Bazzi, Parviz; Daneshi, Adel; Sahrapoor, Azam; O'Connor, William J; Rahbar, Ali Reza

    2015-03-01

    Recently the role of adipocytokines in relationship to incidence of diabetes has been demonstrated. One of the medicinal plants that are used in the treatment of diabetes is stevia. This study investigates the effect of stevia on serum omentin and visfatin levels as novel adipocytokines in diabetic induced rats to find potential mechanisms for the anti hyperglycemic effect of stevia. Forty male wistar rats weighing 180-250 g were induced with diabetes by intraperitoneal injection of streptozotocin (STZ). The animals were divided into 5 groups of 8. Rats in group 1 (non-diabetic control) and group 2 (diabetic control) were treated with distilled water, and the rats in the treated groups, group 3 (T250), group 4 (T500), and group 5 (T750) were treated with stevia, gavaged every day at 9 a.m. in doses of 250, 500, and 750 mg/kg, respectively. At the end of the study significant reductions in fasting blood sugar (FBS), the homeostasis model assessment insulin resistance (HOMA-IR), triglyceride (TG), alkaline phosphatase (ALP), and Omentin level were found in groups 3 and 4 in comparison with group 2. Pancreatic histopathology slides demonstrated that stevia extract did not induce any increase in the number of ?-cells. The conclusion is that prescription of stevia in the doses of 250 and 500 mg/kg/d decreases the omentin level indirectly via activating insulin sensitivity and lowering blood glucose in STZ-induced diabetic rats. PMID:24689449

  17. Hypoglycemic Effects of Exo-biopolymers Produced by Five Different Medicinal Mushrooms in STZ-induced Diabetic Rats

    PubMed Central

    Yang, Byung-Keun; Kim, Guk-Nam; Jeong, Yong-Tae; Jeong, Hun; Mehta, Pradeep

    2008-01-01

    Hypoglycemic effects of exo-biopolymers (EBP) produced by submerged mycelial cultures of Coriolus versicolor, Cordyceps sinensis, Paecilomyces japonica, Armillariella mellea, and Fomes fomentarius were investigated in streptozotocin (STZ)-induced diabetic rats. The rats from each experimental group were orally administered with EBPs (100 mg/kg BW) daily for 2 weeks. Though the hypoglycemic effect was achieved in all the cases, however, C. versicolor EBP proved as the most potent one. The administration of the C. versicolor EBP substantially reduced (29.9%) the plasma glucose level as compared to the saline administered group (control). It also reduced the plasma total cholesterol (TC), triglyceride (TG), aspartate aminotransferase (AST) and, alanine aminotransferase (ALT) levels by 9.22, 23.83, 16.93, and 27.31%, respectively. The sugar and amino acid compositions of this EBP were also analyzed in detail. PMID:23997607

  18. Increased peripherin in sympathetic axons innervating plantar metatarsal arteries in STZ-induced type I diabetic rats

    PubMed Central

    Johansen, Niloufer J.; Frugier, Tony; Hunne, Billie; Brock, James A.

    2014-01-01

    A common characteristic of axonopathy is the abnormal accumulation of cytoskeletal proteins. We recently reported that streptozotocin (STZ)-induced type 1 diabetes produced a change in the morphology of sympathetic nerve fibers supplying rat plantar metatarsal arteries (PMAs). Here we investigated whether these morphological changes are associated with axonal accumulation of the type III intermediate filament peripherin and the microtubule protein β-tubulin III, as both are implicated in axonal remodeling. PMAs from hyperglycemic STZ-treated rats receiving a low dose of insulin (STZ-LI) were compared with those from normoglycemic STZ-treated rats receiving a high dose of insulin (STZ-HI) and vehicle-treated controls. Western blotting revealed an increase in protein expression level for peripherin in PMAs from STZ-LI rats but no change in that for β-tubulin III. In addition, there was an increase in the number of peripherin immunoreactive nerve fibers in the perivascular nerve plexus of PMAs from STZ-LI rats. Co-labeling for peripherin and neuropeptide Y (a marker for sympathetic axons) revealed that peripherin immunoreactivity increased in sympathetic axons. None of these changes were detected in PMAs from STZ-HI rats, indicating that increased peripherin in sympathetic axons of STZ-LI rats is likely due to hyperglycemia and provides a marker of diabetes-induced nerve damage. PMID:24847201

  19. Gmelina arborea Roxb. (Family: Verbenaceae) Extract Upregulates the ?-Cell Regeneration in STZ Induced Diabetic Rats.

    PubMed

    Attanayake, Anoja Priyadarshani; Jayatilaka, Kamani Ayoma Perera Wijewardana; Pathirana, Chitra; Mudduwa, Lakmini Kumari Boralugoda

    2016-01-01

    Gmelina arborea Roxb. (common name: Et-demata, Family: Verbenaceae) has been used traditionally in Sri Lanka as a remedy against diabetes mellitus. The objective of the present study was to evaluate antidiabetic mechanisms of the aqueous bark extract of G. arborea in streptozotocin induced (STZ) diabetic male Wistar rats. Aqueous bark extract of G. arborea (1.00?g/kg) and glibenclamide as the standard drug (0.50?mg/kg) were administered orally using a gavage to STZ diabetic rats (65?mg/kg, ip) for 30 days. The antidiabetic mechanisms of aqueous extract of G. arborea (1.00?g/kg) were determined at the end of the experiment. The fasting blood glucose concentration was significantly lowered and the serum insulin and C-peptide concentrations were increased by 57% and 39% in plant extract treated rats on day 30, respectively (p < 0.05). The histopathology and immunohistochemistry results of the plant extract treated group showed a regenerative effect on ?-cells of the pancreas in diabetic rats. In addition, serum lipid parameters were improved in G. arborea extract treated diabetic rats. The results revealed that the aqueous stem bark extract of G. arborea (1.00?g/kg) showed beneficial effects against diabetes mellitus through upregulating the ?-cell regeneration and biosynthesis of insulin in diabetic rats. PMID:26881248

  20. Acute administration of diosgenin or dioscorea improves hyperglycemia with increases muscular steroidogenesis in STZ-induced type 1 diabetic rats.

    PubMed

    Sato, K; Fujita, S; Iemitsu, M

    2014-09-01

    Acute dehydroepiandrosterone (DHEA) administration improves hyperglycemia in rats with streptozotocin (STZ)-induced type 1 diabetes mellitus. Diosgenin, a steroid structurally similar to DHEA (dehydroepiandrosterone), is contained highly levels in dioscorea; however, it is still unclear whether this natural product improves hyperglycemia in the type 1 diabetes model rats through an increase muscular GLUT4 signaling. After 1 week of STZ injection, fasting glucose level was measured in blood taken from the tail vein every 30 min for 150 min after injection of diosgenin or dioscorea (3mg/kg). On another day, muscle was resected 150 min after diosgenin or dioscorea injections. Serum DHEA level increased significantly 120 min after diosgenin or dioscorea injections; concomitantly, blood glucose level decreased significantly. Moreover, GLUT4 translocation, as well as phosphorylation of Akt and PKC ?/?, increased significantly by diosgenin or dioscorea administration. However, these effects of diosgenin and dioscorea were blocked by a 5?-reductase inhibitor that inhibits synthesizing dehydrotestosterone (DHT) from testosterone. Additionally, significant correlations were observed between blood glucose level, GLUT4 translocation level, and muscular sex steroid hormone level 150 min after the administrations. These results suggest that the diosgenin-induced increase in the DHEA level may contribute to the improvement of hyperglycemia by activating the muscular GLUT4 signaling pathway in type 1 diabetes model rats. PMID:24607838

  1. Aggravation by vanadium of magnesium deficiency in STZ-induced diabetic rats.

    PubMed

    Bermdez-Pea, M C; Lpez-Chaves, C; Llopis, J; Guerrero-Romero, F; Montes-Bayn, M; Sanz-Medel, A; Snchez-Gonzlez, C

    2013-01-01

    This study examined changes in the metabolism of magnesium (Mg), and related serum parameters, following treatment with vanadium (V) in streptozotocin-diabetic rats. Over a period of five weeks, four groups were examined: control, diabetic, diabetic-treated with 1 mg V/day or 3 mg V/day. The V was supplied in drinking water as bis(maltolato)oxovanadium(IV). The Mg levels were measured in food, faeces, urine, serum, muscle, kidney, liver, spleen, heart and femur. Albumin, uric acid, urea, total-cholesterol, LDL-cholesterol, triglycerides, aspartate-aminotransferase and alkaline-phosphatase were determined in serum. In the diabetic group, Mg retained and Mg content in serum and femur decreased, while levels of uric acid, urea, total-cholesterol, LDL-cholesterol, triglycerides and alkaline-phosphatase and aspartate-aminotransferase activity increased compared with control rats. In the diabetic group treated with 1 mg?V/day, Mg retained, serum levels of Mg, urea and triglycerides, and alkaline-phosphatase activity remained unchanged, while levels of uric acid, total-cholesterol and LDL-cholesterol increased and the Mg content in femur and aspartate-aminotransferase activity decreased compared with the diabetic untreated group. In the diabetic rats treated with 3 mg?V/day, food intake and glycaemia were normal. In this group, Mg content in serum, kidney and femur, levels of urea and aspartate-aminotransferase and alkaline-phosphatase activity decreased, whereas LDL-cholesterol increased, uric acid and total-cholesterol levels remained unchanged in comparison with untreated diabetic rats. In conclusion, although treatment with 3 mg V/day normalised the glycaemia, the hypomagnesaemia and tissue depletion of Mg seen in the diabetic rats, caused by the treatment with V, could have partially contributed to the fact that V did not normalise other serum parameters altered by the diabetes. PMID:23823277

  2. Investigation of metabolic changes in STZ-induced diabetic rats with hyperpolarized [1-13C]acetate

    PubMed Central

    Koellisch, Ulrich; Laustsen, Christoffer; Nørlinger, Thomas S; Østergaard, Jakob Appel; Flyvbjerg, Allan; Gringeri, Concetta V; Menzel, Marion I; Schulte, Rolf F; Haase, Axel; Stødkilde-Jørgensen, Hans

    2015-01-01

    In the metabolism of acetate several enzymes are involved, which play an important role in free fatty acid oxidation. Fatty acid metabolism is altered in diabetes patients and therefore acetate might serve as a marker for pathological changes in the fuel selection of cells, as these changes occur in diabetes patients. Acetylcarnitine is a metabolic product of acetate, which enables its transport into the mitochondria for energy production. This study investigates whether the ratio of acetylcarnitine to acetate, measured by noninvasive hyperpolarized [1-13C]acetate magnetic resonance spectroscopy, could serve as a marker for myocardial, hepatic, and renal metabolic changes in rats with Streptozotocin (STZ)-induced diabetes in vivo. We demonstrate that the conversion of acetate to acetylcarnitine could be detected and quantified in all three organs of interest. More interestingly, we found that the hyperpolarized acetylcarnitine to acetate ratio was independent of blood glucose levels and prolonged hyperglycemia following diabetes induction in a type-1 diabetes model. PMID:26272734

  3. Influence of STZ-induced diabetes on zero-stress states of rat pulmonary and systemic arteries.

    PubMed

    Liu, S Q; Fung, Y C

    1992-02-01

    Zero-stress states of the main pulmonary arteries and aorta and small systemic arteries were determined in 22 nondiabetic and 29 streptozocin (STZ)-induced diabetic rats. The zero-stress state of each vessel was obtained by cutting the vessel transversely into a series of short rings, then cutting each ring radially, which caused the ring to spring open into a sector. Each sector can be characterized by its opening angle. The opening angle has strong regional dependence. In some regions of rat arteries, the opening angle can be greater than 360 degrees. Rats were studied 5, 10, 20, 30, and 40 days after an injection of 75 mg/kg body wt i.v. STZ. During diabetes development, the opening angles in general increased and reached a plateau in approximately 30 days. The maximum change of opening angle over normal lies in the range of 18-105 degrees, depending on location. The pulmonary arteries were affected by diabetes as much as the systemic arteries. The course of change of the opening angle during diabetogenesis was different from those of the serum glucose level and blood pressure. Blood pressure in carotid, external iliac, and pulmonary arteries did not change significantly in diabetogenesis. To clarify the physiological meaning of the opening angle, we measured the circumferential strain in the blood vessel wall in homeostatic condition and the residual strain at the no-load state, with both strains referred to the zero-stress state. We calculated the corresponding stresses in the vessel wall. The circumferential stress in the vessel wall was greatly increased by diabetes; great errors will result if the opening angle is ignored. PMID:1733801

  4. AB196. The long-term administration of tadalafil on STZ-induced diabetic rats with erectile dysfunction via local antioxidative mechanism

    PubMed Central

    Chen, Yun; Dai, Yutian

    2015-01-01

    Objective To clarify the antioxidation role in diabetic ED treatment by a long-term administration of PDE5I. Methods Three groups of Sprague-Dawley rats were utilized: group N, normal control; group D, streptozotocin (STZ) induced diabetic rats as control; group D + T, STZ induced diabetic rats by the intragastric administration with tadalafil for 8 weeks. Results ICP/MAP ratio was significantly higher in group D + T than in group D. The levels of MDA decreased remarkably and the activities of SOD increased significantly of group D + T, compared with group D. The level of mitochondrial membrane potential of cavernous tissue of diabetic rats was partly recovered by tadalafil treatment for 8 weeks. The morphology changes of mitochondria were also ameliorated in group D + T. Conclusions The long-term administration of tadalafil on diabetic rats is proven to partly lessen the oxidative stress lesion of the penis via a local antioxidative stress pathway. Early long-term dosages of tadalafil once daily maybe partly prevent rats from diabetic erectile dysfunction. To our knowledge, this is the first report to reveal the new mechanism on long-term treatment of tadalafil in diabetic ED.

  5. RNA-Seq analysis of glycosylation related gene expression in STZ-induced diabetic rat kidney

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The UT-A1 urea transporter is crucial to the kidney’s ability to generate the concentrated urine. Native UT-A1 from kidney inner medulla (IM) is a heavily glycosylated protein with two glycosylation forms of 97 and 117 kDa. In diabetes, protein abundance, particularly the 117 kD isoform, is si...

  6. Modulation of liver function, antioxidant responses, insulin resistance and glucose transport by Oroxylum indicum stem bark in STZ induced diabetic rats.

    PubMed

    Singh, Jyotsna; Kakkar, Poonam

    2013-12-01

    A decoction of stem bark of Oroxylum indicum Vent. (OI) is taken (2-3 times/day) by the tribal people of Sikkim, India to treat diabetes but scientific validation of its overall potential is lacking. Present study was aimed to assess in vitro antihyperglycemic activity of standardized OI extract using inhibition of α-glucosidase, BSA glycation and enhancement of insulin sensitivity. Antidiabetic and antioxidant modulatory effects of OI extract along with the blood biomarkers of toxic response were studied in streptozotocin (STZ) induced diabetic rats. In vitro analysis showed strong antioxidant capacity of OI -and potential to inhibit BSA glycation and α-glucosidase activity which was comparable to standard counterparts. Extract also improved insulin sensitivity in mature 3T3-L1 adipocytes. In vivo effects of OI extract (oral 250 mg/kg b.wt.) on STZ induced type II diabetic rats normalized the antioxidant status (p≤0.01). Analysis of blood biomarkers of toxic response indicated its safety. Lowering of total cholesterol and HDL levels (p≤0.05) and restoration of glycated Hb (p≤0.01) were also found in OI treated diabetic rats. HOMA-IR, QUICKI analysis along with area under the curve analysis showed the capacity of OI extract to enhance the insulin sensitivity significantly (p≤0.01) which was confirmed by increased GLUT-4 translocation in skeletal muscles. PMID:24140466

  7. Polyploidy Analysis and Attenuation of Oxidative Stress in Hepatic Tissue of STZ-Induced Diabetic Rats Treated with an Aqueous Extract of Vochysia rufa

    PubMed Central

    Moraes, Izabela Barbosa; Manzan-Martins, Camilla; de Gouveia, Neire Moura; Calábria, Luciana Karen; Hiraki, Karen Renata Nakamura; Moraes, Alberto da Silva; Espindola, Foued Salmen

    2015-01-01

    Diabetes mellitus (DM) is characterized by hyperglycemia and alterations in the metabolism of lipids, carbohydrates, and proteins. Due to its hypoglycemic effect Vochysia rufa is frequently used in Uberlandia, Brazil, to treat DM. Despite its popularity, there is little information about its effect on hepatic tissue. Therefore, we evaluated the histoarchitecture, oxidative stress parameters, and polyploidy of liver tissue from streptozotocin- (STZ-) induced diabetic rats treated with aqueous extract of Vochysia rufa (AEV). Histology was determined by fixing the livers, processing, and staining with HE. Oxidative stress was determined by evaluating CAT, GPx, and SOD activity in liver homogenates and hepatic mitochondria fraction and by measuring GST, GSH levels and lipid peroxidation (MDA). Polyploidy was determined by subjecting isolated hepatocyte nuclei to flow cytometry. In the diabetic group, GST activity and GSH rates decreased whereas liver homogenate analysis showed that GPx, SOD activity and MDA increased. AEV treatment restored all parameters to normal levels. The oxidative stress analysis of hepatic mitochondria fraction showed similar results. Lower polyploid cell populations were found in the diabetic rat livers, even after glibenclamide treatment. Thus, AEV treatment efficiently reduced hepatic oxidative stress caused by STZ-induced diabetes and produced no morphological changes in the histological analysis. PMID:25763088

  8. The effect of swimming exercise and powdered-Salicornia herbacea L. ingestion on glucose metabolism in STZ-induced diabetic rats

    PubMed Central

    Lee, Se Sil; Seo, Hyobin; Ryu, Sungpil; Kwon, Tae-Dong

    2015-01-01

    Purpose The purpose of this study is to observe the effects of Salicornia herbacea L. powder ingestion on carbohydrate metabolism in STZ-induced diabetic rats. Methods To achieve this objective, 35 Sprague-Dawley male rats were raised with feed mixed with Salicornia herbacia L. powder and given specific periods to swim for 5 weeks. There was no significant difference in the insulin increase rate while ingesting Salicornia herbacea L. powder and simultaneously exercising. Results Compared to the diabetes mellitus group, HOMA-IR was significantly decreased in the diabetes mellitus + exercise group, diabetes mellitus + Salicornia herbacea group, and the diabetes mellitus + Salicornia herbacea + exercise group. However, changes in blood glucose were significant in each group. Thus, for the result of GLUT-4 and GLUT-2, which are the glycose transporters of the liver and muscle, diabetes mellitus + exercise group, diabetes mellitus + Salicornia herbacea group, and diabetes mellitus + Salicornia herbacea + exercise group showed significantly higher expressions. The glycogen concentration of the liver and muscle was significantly increased in the diabetes mellitus + exercise group, diabetes mellitus + Salicornia herbacea group, and diabetes mellitus + Salicornia herbacea + exercise group. Conclusion With the results above, it seems that taking Salicornia herbacea L. powder and exercise will help prevent various diabetic complications. Therefore, the findings of this study could justify Salicornia herbacea L. powder with its basal data of physiological activities and pharmacological components as a type of health functional food. PMID:26525167

  9. Evaluation of the Effect of Different Doses of Low Energy Shock Wave Therapy on the Erectile Function of Streptozotocin (STZ)-Induced Diabetic Rats

    PubMed Central

    Liu, Jing; Zhou, Feng; Li, Guang-Yong; Wang, Lin; Li, Hui-Xi; Bai, Guang-Yi; Guan, Rui-Li; Xu, Yong-De; Gao, Ze-Zhu; Tian, Wen-Jie; Xin, Zhong-Cheng

    2013-01-01

    To investigate the therapeutic effect of different doses of low energy shock wave therapy (LESWT) on the erectile dysfunction (ED) in streptozotocin (STZ) induced diabetic rats. SD rats (n = 75) were randomly divided into 5 groups (normal control, diabetic control, 3 different dose LESWT treated diabetic groups). Diabetic rats were induced by intra-peritoneal injection of STZ (60 mg/kg) and rats with fasting blood glucose ? 300 mg/dL were selected as diabetic models. Twelve weeks later, different doses of LESWT (100, 200 and 300 shocks each time) treatment on penises were used to treat ED (7.33 MPa, 2 shocks/s) three times a week for two weeks. The erectile function was evaluated by intracavernous pressure (ICP) after 1 week washout period. Then the penises were harvested for histological study. The results showed LESWT could significantly improve the erectile function of diabetic rats, increase smooth muscle and endothelial contents, up-regulate the expression of ?-SMA, vWF, nNOS and VEGF, and down- regulate the expression of RAGE in corpus cavernosum. The therapeutic effect might relate to treatment dose positively, and the maximal therapeutic effect was noted in the LESWT300 group. Consequently, 300 shocks each time might be the ideal LESWT dose for diabetic ED treatment. PMID:23698784

  10. Antidiabetic and Hypolipidemic Activities of Curculigo latifolia Fruit:Root Extract in High Fat Fed Diet and Low Dose STZ Induced Diabetic Rats

    PubMed Central

    Ishak, Nur Akmal; Ismail, Maznah; Hamid, Muhajir; Ahmad, Zalinah; Abd Ghafar, Siti Aisyah

    2013-01-01

    Curculigo latifolia fruit is used as alternative sweetener while root is used as alternative treatment for diuretic and urinary problems. The antidiabetic and hypolipidemic activities of C. latifolia fruit:root aqueous extract in high fat diet (HFD) and 40 mg streptozotocin (STZ) induced diabetic rats through expression of genes involved in glucose and lipid metabolisms were investigated. Diabetic rats were treated with C. latifolia fruit:root extract for 4 weeks. Plasma glucose, insulin, adiponectin, lipid profiles, alanine aminotransferase (ALT), gamma glutamyltransferase (GGT), urea, and creatinine levels were measured before and after treatments. Regulations of selected genes involved in glucose and lipid metabolisms were determined. Results showed the significant (P < 0.05) increase in body weight, high density lipoprotein (HDL), insulin, and adiponectin levels and decreased glucose, total cholesterol (TC), triglycerides (TG), low density lipoprotein (LDL), urea, creatinine, ALT, and GGT levels in diabetic rats after 4 weeks treatment. Furthermore, C. latifolia fruit:root extract significantly increased the expression of IRS-1, IGF-1, GLUT4, PPARα, PPARγ, AdipoR1, AdipoR2, leptin, LPL, and lipase genes in adipose and muscle tissues in diabetic rats. These results suggest that C. latifolia fruit:root extract exerts antidiabetic and hypolipidemic effects through altering regulation genes in glucose and lipid metabolisms in diabetic rats. PMID:23762147

  11. Hypoglycemic effect of Gynostemma pentaphyllum saponins by enhancing the Nrf2 signaling pathway in STZ-inducing diabetic rats.

    PubMed

    Gao, Dawei; Zhao, Min; Qi, Ximing; Liu, Yanping; Li, Nan; Liu, Zhiwei; Bian, Yanhong

    2016-02-01

    Gynostemma pentaphyllum (GP) is a natural plant resources for diabetes therapy, however, there is little research on the mechanisms of GP. The present study was undertaken to characterize if G. pentaphyllum saponins (GPs) is the principal active compound of GP responsible for anti-diabetes, and to examine the relativity between blood glucose modulate and antioxidation. The GPs-treated streptozotocin diabetic rats had a more effective hypoglycemic status than those of diabetic control rats, which also ameliorate dyslipidemia. GPs has increased SOD and GSH-px activities, and the spleen and thymus indexes in diabetic rats. The insulin levels in the GPs-treated groups were significantly higher than diabetic control group. Our finding provides a new insight into the application of GPs for the treatment of oxidative stress related diseases. PMID:25066072

  12. Gmelina arborea Roxb. (Family: Verbenaceae) Extract Upregulates the β-Cell Regeneration in STZ Induced Diabetic Rats

    PubMed Central

    Attanayake, Anoja Priyadarshani; Jayatilaka, Kamani Ayoma Perera Wijewardana; Pathirana, Chitra; Mudduwa, Lakmini Kumari Boralugoda

    2016-01-01

    Gmelina arborea Roxb. (common name: Et-demata, Family: Verbenaceae) has been used traditionally in Sri Lanka as a remedy against diabetes mellitus. The objective of the present study was to evaluate antidiabetic mechanisms of the aqueous bark extract of G. arborea in streptozotocin induced (STZ) diabetic male Wistar rats. Aqueous bark extract of G. arborea (1.00 g/kg) and glibenclamide as the standard drug (0.50 mg/kg) were administered orally using a gavage to STZ diabetic rats (65 mg/kg, ip) for 30 days. The antidiabetic mechanisms of aqueous extract of G. arborea (1.00 g/kg) were determined at the end of the experiment. The fasting blood glucose concentration was significantly lowered and the serum insulin and C-peptide concentrations were increased by 57% and 39% in plant extract treated rats on day 30, respectively (p < 0.05). The histopathology and immunohistochemistry results of the plant extract treated group showed a regenerative effect on β-cells of the pancreas in diabetic rats. In addition, serum lipid parameters were improved in G. arborea extract treated diabetic rats. The results revealed that the aqueous stem bark extract of G. arborea (1.00 g/kg) showed beneficial effects against diabetes mellitus through upregulating the β-cell regeneration and biosynthesis of insulin in diabetic rats. PMID:26881248

  13. Comparing the Effects of Ginger and Glibenclamide on Dihydroxybenzoic Metabolites Produced in Stz-Induced Diabetic Rats

    PubMed Central

    Ahmadi, Ramesh; Pishghadam, Saeede; Mollaamine, Fatemeh; Zand Monfared, Mohammad Reza

    2013-01-01

    Background: The aim of the present study was to investigate the effect of ginger and glibenclamide on oxidative stress markers. Oxidative stress is caused by an unbalance between a relative overload of oxidants and depletion of antioxidants, as implicated in the pathogenesis of several chronic diseases, including atherosclerosis and diabetes mellitus. Regarding the role of oxidative stress in the pathogenesis of diabetes mellitus, we investigated the effect of ginger and glibenclamide in diabetic rats induced bystreptozocin (STZ). Objectives: This study assessed the effects of ginger and glibenclamide on dihydroxybenzoic acid metabolites in diabetic rats. Materials and Methods: In this study 30 Wistar strain male rats were divided into five groups: Group 1: Normal control receiving normal saline (0.9 0/0), Group 2: control DMSO (Dimethyl sulfoxide) (as solvent of glibenclamide), Group 3: Diabetic control receiving Streptozocin (STZ ) (50 mg/kg) ,Group 4: diabetic+ Ginger Extract: this group received ginger ethanolic extract (200 mg/kg) via IP (Intraperitoneally) injection for 30 days, and Group 5 diabetic rats received glibenclamide (0.5 m/kg). Production of hydroxyl radicals was examined in the diabetic rats induced by streptozocin. Hydroxyl radicals were generated in plasma of the hyperglycemic rats, and were quantitatively assayed by trapping hydroxyl radicals with salicylic acid so as to produce 2,3-and 2,5-dihydroxybenzoic acid. Results: Production of hydroxyl radicals increased; therefore, by using salicylic acid, hydroxyl radicals were trapped and 2,3dihydroxybenzoic acid and 2,5dihydroxybenzoic acid metabolites were formed then measured by HPLC and spectrophotometer. Rats receiving ginger extract and glibenclamide showed decreased level of metabolites compared to the diabetic controls (P <0/001). This means that antioxidants act as scavenger of free radicals. Conclusions: Comparative effect of ginger and glibenclamide also showed that glibenclamide has antioxidant effect as a scavenger of free radical, but ginger is more capable of eliminating them. PMID:24719624

  14. Telmisartan ameliorates germ cell toxicity in the STZ-induced diabetic rat: studies on possible molecular mechanisms.

    PubMed

    Kushwaha, S; Jena, G B

    2013-07-01

    Testicular damage is a common clinical problem in diabetic individuals that severely affects the quality of life. The present study investigates the possible protective mechanisms of telmisartan, an angiotensin II-receptor antagonist in the germ cell of diabetic rat. Male SD rats were used and randomized into six groups: control, telmisartan control, diabetic control and diabetic group treated with telmisartan at the doses of 3, 6 and 12mg/kg/day, per oral for 4 weeks. Diabetes was induced by injecting a single dose of streptozotocin (STZ), (55mg/kg) dissolved in ice-cold 10mM citrate buffer; pH 4.4 and administered i.p. immediately after preparation to the SD rats. At the end of the study, rats were sacrificed and the levels of nitrite, superoxide, malondialdehyde (MDA), glutathione (reduced and peroxidase) and superoxide dismutase (SOD) were measured. Germ cell toxicity was evaluated by using sperm count, sperm comet assay, histology of testes and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. Further to confirm the oxidative and nitrosative damage, immunohistological quantification of 8-oxo-dG (8-oxo-7,8-dihydro-2'-deoxyguanosine) and 3-nitrotyrosine were evaluated respectively. Results showed that telmisartan significantly restored the levels of nitrite, superoxide, malondialdehyde, and glutathione and superoxide dismutase in diabetic testes. Further, telmisartan significantly increased the sperm counts, reduced apoptotic cell death, sperm DNA damage, oxidative and nitrosative damage in diabetic rat. Western blot analysis showed that telmisartan reduced the testicular inflammation and cell death by down-regulating the expression of NF-?B, IL-6, TNF-?, p-ERK1/2, iNOS, caspase-3 and increasing the PPAR-? expression. Results clearly indicate that telmisartan significantly reduced the both oxidative and nitrosative stress, inflammation and cell death in diabetic testes. The present results confirmed that telmisartan exhibited beneficial role in the germ cell of diabetic rat. PMID:23648321

  15. RNA-seq analysis of glycosylation related gene expression in STZ-induced diabetic rat kidney inner medulla

    PubMed Central

    Qian, Xiaoqian; Li, Xuechen; Ilori, Titilayo O.; Klein, Janet D.; Hughey, Rebecca P.; Li, Cong-jun; Alli, Abdel A.; Guo, Zhengyu; Yu, Peng; Song, Xiang; Chen, Guangping

    2015-01-01

    The UT-A1 urea transporter is crucial to the kidney's ability to generate concentrated urine. Native UT-A1 from kidney inner medulla (IM) is a heavily glycosylated protein with two glycosylation forms of 97 and 117 kDa. In diabetes, UT-A1 protein abundance, particularly the 117 kD isoform, is significantly increased corresponding to an increased urea permeability in perfused IM collecting ducts, which plays an important role in preventing the osmotic diuresis caused by glucosuria. However, how the glycan carbohydrate structure change and the glycan related enzymes regulate kidney urea transport activity, particularly under diabetic condition, is largely unknown. In this study, using sugar-specific binding lectins, we found that the carbohydrate structure of UT-A1 is changed with increased amounts of sialic acid, fucose, and increased glycan branching under diabetic conditions. These changes were accompanied by altered UT-A1 association with the galectin proteins, β-galactoside glycan binding proteins. To explore the molecular basis of the alterations of glycan structures, the highly sensitive next generation sequencing (NGS) technology, Illumina RNA-seq, was employed to analyze genes involved in the process of UT-A1 glycosylation using streptozotocin (STZ)—induced diabetic rat kidney. Differential gene expression analysis combining with quantitative PCR revealed that expression of a number of important glycosylation related genes were changed under diabetic conditions. These genes include the glycosyltransferase genes Mgat4a, the sialylation enzymes St3gal1 and St3gal4 and glycan binding protein galectin-3, -5, -8, and -9. In contrast, although highly expressed in kidney IM, the glycosyltransferase genes Mgat1, Mgat2, and fucosyltransferase Fut8, did not show any changes. Conclusions: In diabetes, not only is UT-A1 protein abundance increased but the protein's glycan structure is also significantly changed. UT-A1 protein becomes highly sialylated, fucosylated and branched. Consistently, a number of crucial glycosylation related genes are changed under diabetic conditions. The alteration of these genes may contribute to changes in the UT-A1 glycan structure and therefore modulate kidney urea transport activity and alleviate osmotic diuresis caused by glucosuria in diabetes. PMID:26483702

  16. The Effect of Angipars on Diabetic Neuropathy in STZ-Induced Diabetic Male Rats: A Study on Behavioral, Electrophysiological, Sciatic Histological and Ultrastructural Indices

    PubMed Central

    Zangiabadi, Nasser; Mohtashami, Hossein; Hojatipour, Mahboobeh; Jafari, Mandana; Asadi-Shekaari, Majid; Shabani, Mohammad

    2014-01-01

    Diabetes mellitus is the most common metabolic disease with a high prevalence rate in human society that eventually leads to the peripheral nervous system complications in a great number of patients. In the present study, the effects of Angipars on nerve conduction velocity, histological alterations, and behavioral indices were investigated. Diabetes was induced in male rats by intraperitoneal injection of streptozotocin (STZ). Six weeks after STZ injection, animals were divided into five groups control, vehicle, and 3 experimental groups. The vehicle group received 1?mL distilled water daily for two weeks and three experimental groups received, respectively, intraperitoneal injection of 5, 10, and 20?mg/kg Angipars daily for two weeks. Intraperitoneal injection of Angipars, in some extent, could significantly improve behavioral indices of the experimental groups as compared to the vehicle group. Furthermore, mean nerve conduction velocity in the vehicle group showed significant difference with that in the control and the 2nd experimental groups; therefore, Angipars could increase nerve conduction velocity in neuropathic rats. Overall, Angipars exerted positive effects on the treatment and reduction of physiologic symptoms and improvement of sciatic morphological injuries in neuropathic rats. PMID:25614895

  17. Co-administration of Grape Seed Extract and Exercise Training Improves Endothelial Dysfunction of Coronary Vascular Bed of STZ-Induced Diabetic Rats

    PubMed Central

    Badavi, Mohammad; Abedi, Hassan Ali; Sarkaki, Ali Reza; Dianat, Mahin

    2013-01-01

    Background One of the known complications of diabetes mellitus is vascular dysfunction. Inability of the coronary vascular response to cardiac hyperactivity might cause a higher incidence of ischemic heart disease in diabetic subjects. It has been indicated that regular exercise training and antioxidants could prevent diabetic cardiovascular problems enhanced by vascular damage. Objectives The aim of this study was to determine the effects of grape seed extract (as antioxidant), with and without exercise training on coronary vascular function in streptozotocin induced diabetic rats. Materials and Methods Fifty male Wistar rats weighing 200 232 grams were randomly divided into five groups of 10 rats each: sedentary control, sedentary diabetic, trained diabetic, grape seed extract (200 mg/kg) treated sedentary diabetic and, grape seed extract treated trained diabetic. Diabetes was induced by one intraperitoneal injection of streptozotocin. After eight weeks, coronary vascular responses to vasoactive agents were determined. Results The endothelium dependent vasorelaxation to acetylcholine was reduced significantly in diabetic animals; exercise training or grape seed extract administration partially improves this response. However, exercise training in combination with grape seed extract restores endothelial function completely. The endothelium independent vasorelaxation to sodium nitroprusside was improved by combination of exercise training and grape seed extract. On the other hand, the basal perfusion pressure and vasoconstrictive response to phenylephrine did not change significantly. Conclusions The data indicated that co-administration of grape seed extract and exercise training had more significant effects than exercise training or grape seed extract alone; this may constitute a convenient and inexpensive therapeutic approach to diabetic vascular complications. PMID:24693368

  18. Protective effect and potential mechanism of Ginkgo biloba extract EGb 761 on STZ-induced neuropathic pain in rats.

    PubMed

    Taliyan, Rajeev; Sharma, P L

    2012-12-01

    Diabetes induced neuropathic pain is recognized as one of the most difficult types of pain to treat with conventional analgaesics. EGb 761 is a standardized extract of Ginkgo biloba that has analgaesic and antiinflammatory properties and modulatory effects on key pain-related molecules. We examined the effect of EGb 761 on streptozotocin (STZ)-induced neuropathic pain behaviours and assessed its mechanism of action. Streptozotocin (20 mg/kg i.p for 5 days) was administered to induce experimental diabetes. Pain hypersensitivity to radiant heat was measured using the Dynamic Plantar Aesthesiometer to test the pain threshold. Diabetic rats exhibited mechanical allodynia and thermal hyperanalgaesia after the third week of STZ injection and concomitantly increased thiobarbituric acid reactive substance and nitric oxide concentration. The antioxidant enzymes level of superoxide dismutase and catalase was markedly reduced in STZ-diabetic rats (p < 0.05). Systemic administration of EGb 761 (25, 50 and 100 mg/kg), starting after the third week following STZ injection, dose-dependently reversed STZ-induced thermal hyperanalgaesia and mechanical allodynia. Moreover, it reduced oxidonitrosative stress and concomitantly restored the level of antioxidant enzymes (p < 0.05) as compared with untreated diabetic rats. These results suggest that EGb 761 attenuated STZ-induced neuropathic pain behaviours by inhibiting oxidative and nitrosative stress and may constitute a new approach for treatment of painful diabetic neuropathy. PMID:22422566

  19. Changes in Iron Metabolism and Oxidative Status in STZ-Induced Diabetic Rats Treated with Bis(maltolato) Oxovanadium (IV) as an Antidiabetic Agent

    PubMed Central

    Snchez-Gonzlez, Cristina; Lpez-Chaves, Carlos; Trenzado, Cristina E.; Aranda, Pilar; Lpez-Jurado, Mara; Gmez-Aracena, Jorge; Montes-Bayn, Mara; Sanz-Medel, Alfredo; Llopis, Juan

    2014-01-01

    The role of vanadium as a micronutrient and hypoglycaemic agent has yet to be fully clarified. The present study was undertaken to investigate changes in the metabolism of iron and in antioxidant defences of diabetic STZ rats following treatment with vanadium. Four groups were examined: control; diabetic; diabetic treated with 1?mgV/day; and Diabetic treated with 3?mgV/day. The vanadium was supplied in drinking water as bis(maltolato) oxovanadium (IV) (BMOV). The experiment had a duration of five weeks. Iron was measured in food, faeces, urine, serum, muscle, kidney, liver, spleen, and femur. Superoxide dismutase, catalase, NAD(P)H: quinone-oxidoreductase-1 (NQO1) activity, and protein carbonyl group levels in the liver were determined. In the diabetic rats, higher levels of Fe absorbed, Fe content in kidney, muscle, and femur, and NQO1 activity were recorded, together with decreased catalase activity, in comparison with the control rats. In the rats treated with 3?mgV/day, there was a significant decrease in fasting glycaemia, Fe content in the liver, spleen, and heart, catalase activity, and levels of protein carbonyl groups in comparison with the diabetic group. In conclusion BMOV was a dose-dependent hypoglycaemic agent. Treatment with 3?mgV/day provoked increased Fe deposits in the tissues, which promoted a protein oxidative damage in the liver. PMID:24511298

  20. Virus-Mediated Knockdown of Nav1.3 in Dorsal Root Ganglia of STZ-Induced Diabetic Rats Alleviates Tactile Allodynia.

    PubMed

    Tan, Andrew M; Samad, Omar A; Dib-Hajj, Sulayman D; Waxman, Stephen G

    2015-01-01

    Diabetic neuropathic pain affects a substantial number of people and represents a major public health problem. Available clinical treatments for diabetic neuropathic pain remain only partially effective and many of these treatments carry the burden of side effects or the risk of dependence. The misexpression of sodium channels within nociceptive neurons contributes to abnormal electrical activity associated with neuropathic pain. Voltage-gated sodium channel Nav1.3 produces tetrodotoxin-sensitive sodium currents with rapid repriming kinetics and has been shown to contribute to neuronal hyperexcitability and ectopic firing in injured neurons. Suppression of Nav1.3 activity can attenuate neuropathic pain induced by peripheral nerve injury. Previous studies have shown that expression of Nav1.3 is upregulated in dorsal root ganglion (DRG) neurons of diabetic rats that exhibit neuropathic pain. Here, we hypothesized that viral-mediated knockdown of Nav1.3 in painful diabetic neuropathy would reduce neuropathic pain. We used a validated recombinant adeno-associated virus (AAV)-shRNA-Nav1.3 vector to knockdown expression of Nav1.3, via a clinically applicable intrathecal injection method. Three weeks following vector administration, we observed a significant rate of transduction in DRGs of diabetic rats that concomitantly reduced neuronal excitability of dorsal horn neurons and reduced behavioral evidence of tactile allodynia. Taken together, these findings offer a novel gene therapy approach for addressing chronic diabetic neuropathic pain. PMID:26101954

  1. Virus-Mediated Knockdown of Nav1.3 in Dorsal Root Ganglia of STZ-Induced Diabetic Rats Alleviates Tactile Allodynia

    PubMed Central

    Tan, Andrew M; Samad, Omar A; Dib-Hajj, Sulayman D; Waxman, Stephen G

    2015-01-01

    Diabetic neuropathic pain affects a substantial number of people and represents a major public health problem. Available clinical treatments for diabetic neuropathic pain remain only partially effective and many of these treatments carry the burden of side effects or the risk of dependence. The misexpression of sodium channels within nociceptive neurons contributes to abnormal electrical activity associated with neuropathic pain. Voltage-gated sodium channel Nav1.3 produces tetrodotoxin-sensitive sodium currents with rapid repriming kinetics and has been shown to contribute to neuronal hyperexcitability and ectopic firing in injured neurons. Suppression of Nav1.3 activity can attenuate neuropathic pain induced by peripheral nerve injury. Previous studies have shown that expression of Nav1.3 is upregulated in dorsal root ganglion (DRG) neurons of diabetic rats that exhibit neuropathic pain. Here, we hypothesized that viral-mediated knockdown of Nav1.3 in painful diabetic neuropathy would reduce neuropathic pain. We used a validated recombinant adeno-associated virus (AAV)-shRNA-Nav1.3 vector to knockdown expression of Nav1.3, via a clinically applicable intrathecal injection method. Three weeks following vector administration, we observed a significant rate of transduction in DRGs of diabetic rats that concomitantly reduced neuronal excitability of dorsal horn neurons and reduced behavioral evidence of tactile allodynia. Taken together, these findings offer a novel gene therapy approach for addressing chronic diabetic neuropathic pain. PMID:26101954

  2. Effects of methanolic and butanolic fractions of Allium elburzense Wendelbo bulbs on blood glucose level of normal and STZ-induced diabetic rats

    PubMed Central

    Zolfaghari, B.; Shokoohinia, Y.; Ramezanlou, P.; Sadeghi, A.; Mahmoudzadeh, M.; Minaiyan, M.

    2012-01-01

    Allium elburzense (A. elborzense, Alliaceae), a plant rich in saponins, is an edible vegetable in northern Iran with a folk background use as antidiabetic which has not yet been examined for this indication. To evaluate the antidiabetic potential of A. elburzense, its hydroalcoholic (HdAE) and butanolic extracts (BuE) were examined. The acute (1, 2, 3, 4, 8 h) and sub-acute (11 days) effects of oral (p.o.) and intraperitoneal (i.p.) administration of HdAE and BuE of A. elburzense bulbs in different doses were evaluated on blood glucose levels of normal and streptozotocin (STZ, 55 mg/kg body weight)-induced diabetic rats. Glibenclamide (1 mg/kg b.w.) was used as reference drug. Sub-acute treatment with HdAE for 11 days reduced significantly blood glucose levels in diabetic rats (at least P<0.05), while BuE was effective only following i.p. administration (P<0.01). Acute administration did not reduce blood glucose level in normal and diabetic animals. It is concluded that HdAE of A. elburzense exhibited a significant antihyperglycemic activity following chronic administration. These results provide evidence for potential use of A. elburzense in diabetes mellitus considering the fact that this plant is endemic to a location of Iran where diabetes is a high prevalence disorder. PMID:23248670

  3. Effects of L-3-n-butylphthalide on cognitive dysfunction and NR2B expression in hippocampus of streptozotocin (STZ)-induced diabetic rats.

    PubMed

    Li, Jie; Zhang, Songyun; Zhang, Lihui; Wang, Ruiying; Wang, Mian

    2015-01-01

    Diabetes mellitus is associated with rapid cognitive decline. Currently, there is no effective treatment for cognitive dysfunction induced by diabetes. L-3-n-Butylphthalide (L-NBP) is a nerve protective drug extracted from seeds of celery, which has been proved to improve learning and memory in vascular dementia animal models by improving microcirculation, protecting mitochondria and increasing long-term potentiation (LTP). NR2B, one of the subunits of N-methyl-D-aspartate receptor, has been proved to be an important factor for the formation of LTP. The study aimed to investigate the role of NR2B in cognitive dysfunction in the rats with type 1 diabetes and define the protective effects of L-NBP on cognition. A rat model of type 1 diabetes was established by a single intraperitoneal injection of streptozotocin at 60 mg/kg. Animals were randomly allocated to four groups: normal control (NC); diabetic control (DC); diabetic + low L-NBP (DL, administered L-NBP 60 mg/kg per day for 12 weeks); and diabetic + high L-NBP (DH, administered L-NBP 120 mg/kg per day, for 12 weeks). After 12 weeks, cognitive and memory changes were investigated in the Morris water maze. The expression of NR2B was assessed by real-time polymerase chain reaction, Western blotting, and immunohistochemistry. Our results indicated that the escape latency was significantly increased and the number of crossing platform was significantly decreased in DC group compared to NC group. Also, the expression of NR2B was significantly declined in DC group. However, compared to DC group, the expression of NR2B of the L-NBP-treated groups was significantly increased and the escape latency was shortened with the DH group being the most obvious. Therefore, L-NBP can improve the cognitive function by up-regulating the expression of NR2B in STZ-diabetic rats, which may provide the direction for future diabetic encephalopathy therapy. PMID:25149651

  4. Insulin secreting and alpha-glucosidase inhibitory activity of hexane extract of Annona squamosa Linn. in streptozotocin (STZ) induced diabetic rats.

    PubMed

    Ranjana; Tripathi, Yamini B

    2014-06-01

    The hexane extract of A. squamosa (ASHE) in 100 and 400 mg/kg body weight dose raised the insulin level when compared with Glimepiride (1 mg/kg) and also inhibited alpha-glucosidase activity when compared with Acarbose (10 mg/kg) in streptozotocin induced diabetic rats. The ASHE significantly reduced peak blood glucose (Gp30) and area under curve (AUC) in diabetic rats in oral glucose (OGTT) and oral sucrose (OSTT) tolerance test, but there was more reduction of Gp30 value than AUC in OSTT. Thus, it can be suggested that the ASHE, has hypoglycemic role at 2 levels, i.e. it acts as secretagogue and also inhibits the intestinal enzymes, responsible for glucose metabolism. PMID:24956893

  5. Protection against T1DM-Induced Bone Loss by Zinc Supplementation: Biomechanical, Histomorphometric, and Molecular Analyses in STZ-Induced Diabetic Rats

    PubMed Central

    Bortolin, Raul Hernandes; da Graa Azevedo Abreu, Bento Joo; Abbott Galvo Ururahy, Marcela; Costa de Souza, Karla Simone; Bezerra, Joo Felipe; Bezerra Loureiro, Melina; da Silva, Flvio Santos; Marques, Dfiny Emanuele da Silva; Batista, Anglica Amanda de Sousa; Oliveira, Gisele; Luchessi, Andr Ducati; Lima, Valria Morgiana Gualberto Duarte Moreira; Miranda, Carlos Eduardo Saraiva; Lia Fook, Marcus Vinicius; Almeida, Maria das Graas; de Rezende, Luciana Augusto; de Rezende, Adriana Augusto

    2015-01-01

    Several studies have established an association between diabetes and alterations in bone metabolism; however, the underlying mechanism is not well established. Although zinc is recognized as a potential preventive agent against diabetes-induced bone loss, there is no evidence demonstrating its effect in chronic diabetic conditions. This study evaluated the effects of zinc supplementation in a chronic (90 days) type 1 diabetes-induced bone-loss model. Male Wistar rats were distributed in three groups: control, type 1 diabetes mellitus (T1DM), and T1DM plus zinc supplementation (T1DMS). Serum biochemical analysis; tibia histomorphometric, biomechanical, and collagen-content analyses; and femur mRNA expression were evaluated. Relative to T1DM, the zinc-supplemented group showed increased histomorphometric parameters such as TbWi and BAr and decreased TbSp, increased biomechanical parameters (maximum load, stiffness, ultimate strain, and Youngs modulus), and increased type I collagen content. Interestingly, similar values for these parameters were observed between the T1DMS and control groups. These results demonstrate the protective effect of zinc on the maintenance of bone strength and flexibility. In addition, downregulation of OPG, COL1A, and MMP-9 genes was observed in T1DMS, and the anabolic effects of zinc were evidenced by increased OC expression and serum ALP activity, both related to osteoblastogenesis, demonstrating a positive effect on bone formation. In contrast, T1DM showed excessive bone loss, observed through reduced histomorphometric and biomechanical parameters, characterizing diabetes-associated bone loss. The bone loss was also observed through upregulation of OPG, COL1A, and MMP-9 genes. In conclusion, zinc showed a positive effect on the maintenance of bone architecture and biomechanical parameters. Indeed, OC upregulation and control of expression of OPG, COL1A, and MMP-9 mRNAs, even in chronic hyperglycemia, support an anabolic and protective effect of zinc under chronic diabetic conditions. Furthermore, these results indicate that zinc supplementation could act as a complementary therapy in chronic T1DM. PMID:25933189

  6. Antidiabetic and antioxidant effect of Semecarpus anacardium Linn. nut milk extract in a high-fat diet STZ-induced type 2 diabetic rat model.

    PubMed

    Khan, Haseena Banu Hedayathullah; Vinayagam, Kaladevi Siddhi; Sekar, Ashwini; Palanivelu, Shanthi; Panchanadham, Sachdanandam

    2012-03-01

    Semecarpus anacardium commonly known as marking nut has been used in the Siddha system of medicine against various ailments. The antidiabetic and antioxidant potential of the drug was evaluated in Type 2 diabetic rats induced by feeding a high-fat diet (HFD) for 2 weeks followed by single intraperitoneal injection of streptozotocin (STZ) 35 mg/kg body weight. Three days after STZ induction, the hyperglycemic rats were treated with Semecarpus anacardium nut milk extract (SA) orally at a dosage of 200 mg/kg body weight daily for 30 days. Metformin (500 mg/kg body weight, orally) was used as a reference drug. The fasting blood glucose, insulin, Hb, HbA1c levels, and HOMA-IR and HOMA-β were measured, and also the levels of lipid peroxidation and antioxidant enzymes were observed. SA significantly (p < .05) reduced and normalized blood glucose levels and also decreased the levels of HbA1c as compared with that of HFD STZ control group. SA treatment also significantly (p < .05) increased the levels of antioxidant enzymes while decreasing the levels of lipid peroxidation. The potential antihyperglycemic action and antioxidant role might be due to the presence of flavonoids in the drug. PMID:22432800

  7. Anti-diabetic activity of recombinant irisin in STZ-induced insulin-deficient diabetic mice.

    PubMed

    Duan, Huikun; Ma, Baicheng; Ma, Xiaofeng; Wang, Haisong; Ni, Zaizhong; Wang, Bin; Li, Xiaodan; Jiang, Pingzhe; Umar, Muhammad; Li, Minggang

    2016-03-01

    In order to investigate the hypoglycemic effects and potential mechanism of recombinant irisin on diabetes, STZ-induced diabetic mice were established and treated with irisin. The results showed that daily water and food intake, and blood glucose significantly decreased after various concentrations of recombinant irisin treatment by intraperitoneal injection, of which 1.0mg/kg was the optimal dose for lowering blood glucose. However, the body weight exhibited no significant difference during the treatment within groups, although the 0.9% NaCl treated group showed a trend of decreased body weight and the irisin treated groups showed a tendency of increasing weight. The oral glucose tolerance was improved, and serum insulin and circulating irisin content were significantly elevated in diabetic mice after 1.0mg/kg irisin-injection treatment, compared to diabetic mice treated with 0.9% NaCl. 1.0mg/kg irisin-injection also significantly increased the expression of energy and metabolism-related genes. In addition, oral administration of irisin lowered the blood glucose in diabetic mice. Our data suggested that irisin could lower blood glucose in insulin-deficient diabetic mice, to some extent, through irisin-mediated induction of energy and metabolic genes expression. These observations laid a foundation for the development of irisin-based therapy. PMID:26712701

  8. Anti-diabetic activity of peony seed oil, a new resource food in STZ-induced diabetic mice.

    PubMed

    Su, Jianhui; Wang, Hongxin; Ma, Caoyang; Lou, Zaixiang; Liu, Chengxiang; Tanver Rahman, MdRamim; Gao, Chuanzhong; Nie, Rongjing

    2015-09-01

    This study was conducted to investigate the components of a new resource food in China, peony seed oil (PSO) by GC-MS (gas chromatography-mass spectrometry), its inhibitory effects on carbohydrate hydrolyzing enzymes in vitro and its anti-diabetic effects on mice induced by streptozotocin (STZ). The results showed that peony seed oil showed weak anti-α-amylase activity; however, strong anti-α-glucosidase activity was noted. The GC-MS analysis of the oil showed 9 constituents of which α-linolenic acid was found to be the major component (38.66%), followed by linoleic acid (26.34%) and oleic acid (23.65%). The anti-diabetic potential of peony seed oil was tested in STZ induced diabetic mice. Administration of peony seed oil and glibenclamide reduced the blood glucose level and the area under curve (AUC) in STZ induced diabetic mice. There were significant increases in body weight, liver glycogen content, serum insulin level, high-density lipoprotein cholesterol (HDL-C) and decreases in glycosylated hemoglobin (HbA1C), total serum cholesterol (TC), and triglyceride (TG) in test groups as compared to the untreated diabetic groups. In vivo antioxidant studies on STZ induced diabetic mice revealed the reduction of malondialdehyde (MDA) and increase of glutathione peroxides (GSH-px), superoxide dismutase (SOD), and glutathione (GSH). The results provided a sound rationale for future clinical trials of oral administration of peony seed oil to alleviate postprandial hyperglycemia in streptozotocin-induced diabetic mice. PMID:26245697

  9. Ethanol extract of mango (Mangifera indica L.) peel inhibits α-amylase and α-glucosidase activities, and ameliorates diabetes related biochemical parameters in streptozotocin (STZ)-induced diabetic rats.

    PubMed

    Gondi, Mahendranath; Prasada Rao, U J S

    2015-12-01

    Peel is a major by-product during processing of mango fruit into pulp. Recent report indicates that the whole peel powder ameliorated diabetes. In the present study, ethanolic extract of mango peel was analysed for its bioactive compounds, evaluated for α-amylase and α-glucosidase inhibitory properties, oral glucose tolerance test, antioxidant properties, plasma insulin level and biochemical parameters related to diabetes. In addition to gallic and protocatechuic acids, the extract also had chlorogenic and ferulic acids, which were not reported earlier in mango peel extracts. The peel extract inhibited α-amylase and α-glucosidase activities, with IC50 values of 4.0 and 3.5 μg/ml. Ethanolic extract of peel showed better glucose utilization in oral glucose tolerance test. Treatment of streptozotocin-induced diabetic rats with the extract decreased fasting blood glucose, fructosamine and glycated hemoglobin levels, and increased plasma insulin level. Peel extract treatment decreased malondialdehyde level, but increased the activities of antioxidant enzymes significantly in liver and kidney compared to diabetic rats. These beneficial effects were comparable to metformin, but better than gallic acid treated diabetic rats. The beneficial effects of peel extract may be through different mechanism like increased plasma insulin levels, decreased oxidative stress and inhibition of carbohydrate hydrolyzing enzyme activities by its bioactive compounds. Thus, results suggest that the peel extract can be a potential source of nutraceutical or can be used in functional foods and this is the first report on antidiabetic properties of mango peel extract. PMID:26604360

  10. Insulin and growth hormone-releasing peptide-6 (GHRP-6) have differential beneficial effects on cell turnover in the pituitary, hypothalamus and cerebellum of streptozotocin (STZ)-induced diabetic rats.

    PubMed

    Granado, Miriam; Garca-Cceres, Cristina; Tuda, Mara; Frago, Laura M; Chowen, Julie A; Argente, Jess

    2011-04-30

    Poorly controlled type1 diabetes is associated with hormonal imbalances and increased cell death in different tissues, including the pituitary, hypothalamus and cerebellum. In the pituitary, lactotrophs are the cell population with the greatest increase in cell death, whereas in the hypothalamus and cerebellum astrocytes are most highly affected. Insulin treatment can delay, but does not prevent, diabetic complications. As ghrelin and growth hormone (GH) secretagogues are reported to prevent apoptosis in different tissues, and to modulate glucose homeostasis, a combined hormonal treatment may be beneficial. Hence, we analyzed the effect of insulin and GH-releasing peptide 6 (GHRP-6) on diabetes-induced apoptosis in the pituitary, hypothalamus and cerebellum of diabetic rats. Adult male Wistar rats were made diabetic by streptozotocin injection (65 mg/kg ip) and divided into four groups from diabetes onset: those receiving a daily sc injection of saline (1 ml/kg/day), GHRP-6 (150 ?g/kg/day), insulin (1-8U/day) or insulin plus GHRP-6 for 8 weeks. Control non-diabetic rats received saline (1 ml/kg/day). Diabetes increased cell death in the pituitary, hypothalamus and cerebellum (P<0.05). In the pituitary, insulin treatment prevented diabetes-induced apoptosis (P<0.01), as well as the decline in prolactin and GH mRNA levels (P<0.05). In the hypothalamus, neither insulin nor GHRP-6 decreased diabetes-induced cell death. However, the combined treatment of insulin+GHRP-6 prevented the diabetes induced-decrease in glial fibrillary acidic protein (GFAP) levels (P<0.05). In the cerebellum, although insulin treatment increased GFAP levels (P<0.01), only the combined treatment of insulin+ GHRP-6 decreased diabetes-induced apoptosis (P<0.05). In conclusion, insulin and GHRP-6 exert tissue specific effects in STZ-diabetic rats and act synergistically on some processes. Indeed, insulin treatment does not seem to be effective on preventing some of the diabetes-induced alterations in the central nervous system. PMID:21352888

  11. Selective inhibition of PTEN preserves ischaemic post-conditioning cardioprotection in STZ-induced Type1 diabetic rats: role of the PI3K/Akt and JAK2/STAT3 pathways.

    PubMed

    Xue, Rui; Lei, Shaoqing; Xia, Zhong-Yuan; Wu, Yang; Meng, Qingtao; Zhan, Liying; Su, Wating; Liu, Huimin; Xu, Jinjin; Liu, Zhenzhen; Zhou, Bin; Xia, Zhengyuan

    2016-03-01

    Patients with diabetes are vulnerable to MI/R (myocardial ischaemia/reperfusion) injury, but are not responsive to IPostC (ischaemic post-conditioning) which activates PI3K (phosphoinositide 3-kinase)/Akt (also known as PKB or protein kinase B) and JAK2 (Janus kinase 2)/STAT3 (signal transducer and activator of transcription 3) pathways to confer cardioprotection. We hypothesized that increased cardiac PTEN (phosphatase and tensin homologue deleted on chromosome 10), a major negative regulator of PI3K/Akt, is responsible for the loss of diabetic heart sensitivity to IPostC cardioprotecton. In STZ (streptozotocin)-induced Type1 diabetic rats subjected to MI/R (30min coronary occlusion and 120min reperfusion), the post-ischaemic myocardial infarct size, CK-MB (creatine kinase-MB) and 15-F2t-isoprostane release, as well as cardiac PTEN expression were significantly higher than those in non-diabetic controls, concomitant with more severe cardiac dysfunction and lower cardiac Akt, STAT3 and GSK-3? (glycogen synthase kinase 3?) phosphorylation. IPostC significantly attenuated post-ischaemic infarct size, decreased PTEN expression and further increased Akt, STAT3 and GSK-3? phosphorylation in non-diabetic, but not in diabetic rats. Application of the PTEN inhibitor BpV (bisperoxovanadium) (1.0mg/kg) restored IPostC cardioprotection in diabetic rats. HPostC (hypoxic post-conditioning) in combination with PTEN gene knockdown, but not HPostC alone, significantly reduced H/R (hypoxia/reoxygenation) injury in cardiac H9c2 cells exposed to high glucose as was evident from reduced apoptotic cell death and JC-1 monomer in cells, accompanied by increased phosphorylation of Akt, STAT3 and GSK-3?. PTEN inhibition/gene knockdown mediated restoration of IPostC/HPostC cardioprotection was completely reversed by the PI3K inhibitor wortmannin, and partially reversed by the JAK2 inhibitor AG490. Increased cardiac PTEN, by impairing PI3K/Akt and JAK2/STAT3 pathways, is a major mechanism that rendered diabetic hearts not responsive to post-conditioning cardioprotection. PMID:26666444

  12. Attenuation of hepatotoxicity and oxidative stress in diabetes STZ-induced type 1 by biotin in Swiss albino mice

    PubMed Central

    Aldahmash, Badr Abdullah; El-Nagar, Doaa Mohamed; Ibrahim, Khalid Elfakki

    2015-01-01

    Diabetes mellitus is one of the major health problems. This study was designed to investigate the effect of biotin to regulate blood glucose level, reduced toxicity and oxidative stress in liver of diabetic mice STZ-induced type 1. Male mice were divided into three groups, the first one served as the control group, the second and the third groups received single ip dose of 150 mg/kg of STZ, the second group served as the untreated diabetic group, the third group received daily oral dose of 15 mg/kg of biotin, livers and liver index showed insignificant difference among groups. Blood glucose level showed a significant decrease in treated diabetic mice compared to untreated diabetic mice. Biochemical analysis showed a significant decrease in liver enzymes AST and ALT compared to the control group. Histopathological examination showed severe changes in untreated diabetic liver tissue manifested by dilated portal vein, leukocytic infiltration, fatty degeneration and moderate to severe histopathological score, whereas, treated diabetic mice with biotin showed reduction in hepatotoxicity represented by appearance of relative healthy hepatocytes and normal histopathological score. Immunohistochemistry of acrolein showed intense immunoreactions in liver section of untreated diabetic mice and faint immunoreactions in treated diabetic mice with biotin as evidence to oxidative stress reduction. PMID:26981014

  13. 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

  14. 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, Joo 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

  15. Genetic Deficiency of Anti-Aging Gene Klotho Exacerbates Early Nephropathy in STZ-Induced Diabetes in Male Mice

    PubMed Central

    Lin, Yi; Kuro-o, Makoto

    2013-01-01

    Klotho is a recently discovered anti-aging gene and is primarily expressed in kidneys. In humans, the klotho level decreases with age whereas the prevalence of chronic kidney disease (CKD) increases with age. Diabetic nephropathy is the most common form of CKD, which leads to end-stage renal disease. A decrease in klotho has been found in kidneys of patients with diabetic nephropathy. The purpose of this study is to assess whether klotho gene deficiency affects early diabetic nephropathy in a mouse of model of type 1 diabetes induced by streptozotocin (STZ). Male KL+/? mutant and wild-type mice (68 weeks) were injected with multiple low doses of STZ. Renal functions and renal blood flow were assessed. Kidneys were collected for histological examination and molecular assays of TGF?1 and mammalian targets of rapamycin (mTOR) signaling. Klotho deficiency in KL+/? mutant mice exacerbated STZ-induced increases in urine albumin, blood urea nitrogen, expansion of mesangial matrix in renal glomeruli, and kidney hypertrophy, suggesting a protective role of klotho in kidney function and structure. Klotho deficiency did not affect renal blood flow. Notably, klotho deficiency significantly increased phosphorylation of Smad2, indicating enhanced TGF?1 signaling in kidneys. Klotho deficiency also increased phosphorylation of mTOR and S6 (a downstream effector of mTOR), indicating enhanced mTOR signaling in kidneys of early diabetic mice. Thus, klotho gene deficiency may make kidneys more susceptible to diabetic injury. Klotho gene deficiency exacerbated early diabetic nephropathy via enhancing both TGF?1 and mTOR signaling in kidneys. PMID:23928372

  16. 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

  17. 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

  18. 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

  19. Anti-diabetic effect of Coptis Chinensis polysaccharide in high-fat diet with STZ-induced diabetic mice.

    PubMed

    Jiang, Shuang; Du, Peige; An, Liping; Yuan, Guangxin; Sun, Zhiwei

    2013-04-01

    For the past few years, numerous polysaccharides and polysaccharide-protein complexes have been isolated from plant or animal and used as a promising source of therapeutic agents for diabetes mellitus (DM). In this study, a water-soluble polysaccharide, named as CCPW-1, was extracted and fractioned from the roots of Coptis Chinensis by DEAE Sepharose Fast Flow anion-exchange and Sephadex G-100 column chromatography. The determination of the monosaccharide composition in CCPW-1 with gas chromatography (GC) showed that CCPW-1 was composed of glucose (54.8%), arabinose (22.3%), xylose (11.5%), galactose (7.6%) and galacturonic acid (3.8%). Diabetic mice induced by high-fat diet (HFD) with streptozotocin (STZ) were administered CCPW-1 (100, 50, 25 mg/kg b.w.). Effects of CCPW-1 on bodyweight, fasting blood glucose (FBG), oral glucose tolerance test (OGTT), fasting serum insulin (FINS), total glycerin (TG), total cholesterol (TC), super oxygen dehydrogenises (SOD), catalase (CAT) and methane dicarboxylic aldehyde (MDA) were investigated. CCPW-1 could improve the bodyweight, reduce the content of FBG and enhance FINS level. Meanwhile, CCPW-1 significantly suppressed the rise in blood glucose after 30 min in OGTT. TG and TC levels of diabetic mice also decreased after CCPW-1 treatment. Furthermore, CCPW-1 showed an obvious antioxidant effect through increasing SOD, CAT activities and decreasing MDA content in pancreas. These results indicate that CCPW-1 could be developed to a potent drug used for the treatment of DM in the future. PMID:23295205

  20. Inhibition of JNK by compound C66 prevents pathological changes of the aorta in STZ-induced diabetes

    PubMed Central

    Liu, Yucheng; Wang, Yonggang; Miao, Xiao; Zhou, Shanshan; Tan, Yi; Liang, Guang; Zheng, Yang; Liu, Quan; Sun, Jian; Cai, Lu

    2014-01-01

    Cardiovascular diseases as leading causes of the mortality world-wide are related to diabetes. The present study was to explore the protective effect of curcumin analogue C66 on diabetes-induced pathogenic changes of aortas. Diabetes was induced in male C57BL/6 mice with a single intraperitoneal injection of streptozotocin. Diabetic mice and age-matched non-diabetic mice were randomly treated with either vehicle (Control and Diabetes), C66 (C66 and Diabetes/C66) or c-Jun N-terminal kinase (JNK) inhibitor (sp600125, JNKi and Diabetes/JNKi). All three treatments were given by gavage at 5 mg/kg every other day for 3 months. Aortic inflammation, oxidative stress, fibrosis, cell apoptosis and proliferation, Nrf2 expression and transcription were assessed by immunohistochemical staining for the protein level and real-time PCR method for mRNA level. Diabetes increased aortic wall thickness and structural derangement as well as JNK phosphorylation, all of which were attenuated by C66 treatment as JNKi did. Inhibition of JNK phosphorylation by C66 and JNKi also significantly prevented diabetes-induced increases in inflammation, oxidative and nitrative stress, apoptosis, cell proliferation and fibrosis. Furthermore, inhibition of JNK phosphorylation by C66 and JNKi significantly increased aortic Nrf2 expression and transcription function (e.g. increased expression of Nrf2-downstream genes) in normal and diabetic conditions. These results suggest that diabetes-induced pathological changes in the aorta can be protected by C66 via inhibition of JNK function, accompanied by the up-regulation of Nrf2 expression and function. PMID:24720784

  1. Up-regulation of the Ang II/AT1 receptor may compensate for the loss of gastric antrum ICC via the PI3k/Akt signaling pathway in STZ-induced diabetic mice.

    PubMed

    Zhang, C M; Huang, X; Lu, H L; Meng, X M; Liu, D H; Kim, Young-Chul; Xu, W X

    2016-03-01

    The classic renin-angiotensin system (RAS) is a complex system in which angiotensin II (Ang II) has been identified as an important endogenous regulator that influences both smooth muscle contraction and cell growth. Although a local RAS is known to exist in the gastrointestinal tract, it is unclear whether Ang II is involved in the loss of gastric interstitial cells of Cajal (ICC) in diabetic mice. The present study was designed to investigate the effect of Ang II on ICC survival in streptozotocin (STZ)-induced diabetic mice. Western blot, immunofluorescence, isometric muscle recording, enzyme-linked immunosorbent assay (ELISA) and a cell counting kit-8 were used in this research. Our results demonstrate that the c-Kit and membrane-bound stem cell factor (mSCF) protein expression levels in gastric smooth muscle were decreased in STZ-induced diabetic mice. However, the angiotensin receptor type 1 (AT1R) expression levels in gastric smooth muscle and angiotensin-converting enzyme (ACE) expression levels in gastric mucosa were increased. The effect of Ang II on the tonic contraction of gastric smooth muscle was potentiated in diabetic mice, and the plasma Ang II level was enhanced. Ang II increased mSCF expression, cell proliferation, and Akt-Ser473 phosphorylation in cultured gastric smooth muscle cells (GSMCs). These effects were reduced by specific inhibitors ZD7155 (an AT1R antagonist) and LY294002 (a PI3-kinase inhibitor). Our results suggest that Ang II increases mSCF expression and cell proliferation in cultured GSMCs in a PI3K/Akt signaling-dependent manner. ACE and AT1R up-regulation in the stomach may help compensate for ICC loss in STZ-induced diabetic mice. PMID:26773730

  2. Minocycline attenuates pain by inhibiting spinal microglia activation in diabetic rats.

    PubMed

    Sun, Jin-Shan; Yang, Yu-Jie; Zhang, Yong-Zhen; Huang, Wen; Li, Zhao-Shen; Zhang, Yong

    2015-08-01

    The mechanisms associated with diabetes-induced neuropathic pain are complex and poorly understood. In order to understand the involvement of spinal microglia activity in diabetic pain, the present study investigated whether minocycline treatment is able to attenuate diabetic pain using a rat model. Diabetes was induced using a single intraperitoneal injection of streptozotocin (STZ). Minocycline was then intrathecally administered to the rats. Paw withdrawal threshold (PWT) and paw withdrawal latency (PWL) were tested weekly. The expression of OX-42, Iba-1, phospho-p38 mitogen-activated protein kinase (MAPK), tumor necrosis factor-? (TNF-?), interleukin-1? (IL-1?) and inducible nitric oxide synthase (iNOS), were examined in the spinal cord in order to evaluate the activation of microglia. The present study demonstrated that rats with STZ-induced diabetes exhibited increased mean plasma glucose concentration, decreased mean body weight and significant pain hypersensitivity compared with control rats. PWT and PWL values of rats with STZ-induced diabetes increased following treatment with minocycline. No differences were observed in expression levels of the microglial activity markers (OX-42, Iba-1 and phospho-p38 MAPK) between rats with STZ-induced diabetes and control rats. However, TNF-?, IL-1? and iNOS expression levels were higher in rats with STZ-induced diabetes compared with control rats. Following treatment with minocycline markers of microglial activation, including cytokines and iNOS, were downregulated in rats with STZ-induced diabetes. The results of the present study indicated that minocycline treatment may inhibit spinal microglial activation and attenuate diabetic pain in rats with STZ-induced diabetes. PMID:25955348

  3. Tocotrienol-Rich Fraction from Palm Oil Prevents Oxidative Damage in Diabetic Rats

    PubMed Central

    Matough, Fatmah A.; Budin, Siti B.; Hamid, Zariyantey A.; Abdul-Rahman, Mariati; Al-Wahaibi, Nasar; Mohammed, Jamaludine

    2014-01-01

    Objectives: This study was carried out to determine the effects of tocotrienol-rich fraction (TRF) (200 mg/Kg) on biomarkers of oxidative stress on erythrocyte membranes and leukocyte deoxyribonucleic acid (DNA) damage in streptozotocin (STZ)-induced diabetic rats. Methods: Male rats (n = 40) were divided randomly into four groups of 10: a normal group; a normal group with TRF; a diabetic group, and a diabetic group with TRF. Following four weeks of treatment, fasting blood glucose (FBG) levels, oxidative stress markers and the antioxidant status of the erythrocytes were measured. Results: FBG levels for the STZ-induced diabetic rats were significantly increased (P <0.001) when compared to the normal group and erythrocyte malondialdehyde levels were also significantly higher (P <0.0001) in this group. Decreased levels of reduced glutathione and increased levels of oxidised glutathione (P <0.001) were observed in STZ-induced diabetic rats when compared to the control group and diabetic group with TRF. The results of the superoxide dismutase and glutathione peroxidase activities were significantly lower in the STZ-induced diabetic rats than in the normal group (P <0.001). The levels of DNA damage, measured by the tail length and tail moment of the leukocyte, were significantly higher in STZ-induced diabetic (P <0.0001). TRF supplementation managed to normalise the level of DNA damage in diabetic rats treated with TRF. Conclusion: Daily supplementation with 200 mg/Kg of TRF for four weeks was found to reduce levels of oxidative stress markers by inhibiting lipid peroxidation and increasing the levels of antioxidant status in a prevention trial for STZ-induced diabetic rats. PMID:24516761

  4. Treatment with hydrogen sulfide alleviates streptozotocin-induced diabetic retinopathy in rats

    PubMed Central

    Si, Yan-Fang; Wang, Jun; Guan, Juan; Zhou, Li; Sheng, Yu; Zhao, Juan

    2013-01-01

    Background and Purpose Retinopathy, as a common complication of diabetes, is a leading cause of reduced visual acuity and acquired blindness in the adult population. The aim of present study was to investigate the therapeutic effect of hydrogen sulfide on streptozotocin (STZ)-induced diabetic retinopathy in rats. Experimental Approach Rats were injected with a single i.p. injection of STZ (60 mg·kg−1) to induce diabetic retinopathy. Two weeks later, the rats were treated with NaHS (i.p. injection of 0.1 mL·kg−1·d−1 of 0.28 mol·L−1 NaHS, a donor of H2S) for 14 weeks. Key Results Treatment with H2S had no significant effect on blood glucose in STZ-induced diabetic rats. Treatment with exogenous H2S enhanced H2S levels in both plasma and retinas of STZ-induced diabetic rats. Treatment with H2S in STZ-treated rats improved the retinal neuronal dysfunction marked by enhanced amplitudes of b-waves and oscillatory potentials and expression of synaptophysin and brain-derived neurotrophic factor, alleviated retinal vascular abnormalities marked by reduced retinal vascular permeability and acellular capillary formation, decreased vitreous VEGF content, down-regulated expressions of HIF-1α and VEGFR2, and enhanced occludin expression, and attenuated retinal thickening and suppressed expression of extracellular matrix molecules including laminin β1 and collagen IVα3 expression in retinas of STZ-induced diabetic rats. Treatment with H2S in retinas of STZ-induced diabetic rats abated oxidative stress, alleviated mitochondrial dysfunction, suppressed NF-κB activation and attenuated inflammation. Conclusions and Implications Treatment with H2S alleviates STZ-induced diabetic retinopathy in rats possibly through abating oxidative stress and suppressing inflammation. PMID:23488985

  5. Characteristics of dendroaspis natriuretic peptide and its receptor in streptozotocin-induced diabetic rats.

    PubMed

    Park, Byoung Hyun; Kim, Sun Young; Kim, Soo Mi; Noh, Hye Jung; Cho, Chong Gu; Kim, Sung Zoo

    2015-08-01

    Dendroaspis natriuretic peptide (DNP) shares a functionally important sequence homology with other natriuretic peptides. However, the characteristics of DNP and its receptor in the context of diabetes remafin to be fully elucidated. In the present study, alterations in the plasma levels and tissue contents of DNP and the properties of its receptor in diabetic rats, induced by streptozotocin (STZ) injection, were investigated. The plasma levels of DNP were 90.01 4.12 and 196.68 5.60 pg/ml in the control and STZ-induced diabetic rats, respectively. The tissue contents of DNP in the cardiac atrium, ventricle, renal cortex and inner medulla of the STZ-induced diabetic rats were also significantly increased compared with the control rats. Specific (125)I-DNP-binding sites were located predominantly in the glomeruli and inner medulla of the rat kidney. In the glomeruli of the kidney, the apparent dissociation constants (Kd) of (125)I-DNP in the control and STZ-induced diabetic rats were 0.41 0.03 and 0.56 0.06 nM, respectively. The maximum binding capacities (Bmax) of (125)I-DNP in control and STZ-induced diabetic rats were 2.98 0.21 and 6.22 1.06 fmol/mg protein, respectively. However, no differences were observed in the apparent Kd and Bmax of (125)I-DNP in the inner medulla of the kidney between the control and STZ-induced diabetic rats. In the glomerular and inner medullary kidney membranes, DNP stimulated the production of cyclic guanosine monophosphate (cGMP) in a dose-dependent manner. The magnitude of cGMP production in glomerular membranes was greater in the STZ-induced diabetic rats, whereas the magnitude of cGMP production in the inner medullary membranes was lower in the STZ-induced diabetic rats compared with the control rats. These results indicated that STZ-induced diabetes modulate DNP and its receptor, and also suggested that modulation of the DNP system is involved in the renal function of diabetic animals via the intracellular domain of the kidney NP receptor. PMID:25937111

  6. Protective effect of polysaccharides from Opuntia dillenii Haw. fruits on streptozotocin-induced diabetic rats.

    PubMed

    Gao, Jie; Han, Yu-Lu; Jin, Zheng-Yu; Xu, Xue-Ming; Zha, Xue-Qiang; Chen, Han-Qing; Yin, Yan-Yan

    2015-06-25

    In this study, a novel water-soluble polysaccharide fraction with molecular weight of 6479.1kDa was isolated from the fruits of Opuntia dillenii Haw., which consisted of rhamnose, xylose, mannose and glucose in the molar ratio of 14.99:1.14:1.00:6.47. The protective effect of O. dillenii Haw. fruits polysaccharide (ODFP) against oxidative damage in streptozotocin (STZ)-induced diabetic rats was investigated. The results showed that oral administration of ODFP significantly decreased food intake, water intake, urine production, organ weights and blood glucose level, and increased body weight in STZ-induced diabetic rats. ODFP also significantly increased the activities of SOD, GPx and CAT, and decreased malondialdehyde level in serum, liver, kidney, and pancreas in STZ-induced diabetic rats. Moreover, histopathological examination showed that ODFP could markedly improve the structure integrity of pancreatic islet tissue in STZ-induced diabetic rats. These results suggest that ODFP have hypoglycemic and antioxidant properties and can protect rats from STZ-induced oxidative damage. PMID:25839790

  7. Topical instillation of ciliary neurotrophic factor inhibits retinal degeneration in streptozotocin-induced diabetic rats.

    PubMed

    Aizu, Yoshinori; Katayama, Hiroyuki; Takahama, Sachiko; Hu, Jianguo; Nakagawa, Hachiro; Oyanagi, Kiyomitsu

    2003-11-14

    Intraocular injections of ciliary neurotrophic factor (CNTF) or intraocular adenovirus-mediated CNTF gene transfer have been reported to inhibit retinal alterations in inherited retinal degeneration in mice strains. To investigate whether or not CNTF administered by eye drops prevents retinal degeneration in streptozotocin (STZ)-induced diabetic rats, recombinant CNTF was administered to eyes of diabetic rats (n=20) twice daily for 1 month after the onset of diabetes. The b-wave amplitude of electroretinogram in CNTF-administered diabetic rats was significantly larger than that of diabetic rats, and approached that of the controls. Atrophy of the inner plexiform layer, and cavity formation in the pigment epithelium, which were observed in diabetic rats, were prevented in CNTF-administered diabetic rats. These results indicate that CNTF administration by eye drops prevents retinal degeneration in STZ-induced diabetic rats. PMID:14600499

  8. Effect of Potent Ethyl Acetate Fraction of Stereospermum suaveolens Extract in Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Balasubramanian, T.; Chatterjee, Tapan Kumar; Senthilkumar, G. P.; Mani, Tamizh

    2012-01-01

    To evaluate the antihyperglycemic effect of ethyl acetate fraction of ethanol extract of Stereospermum suaveolens in streptozotocin-(STZ-) induced diabetic rats by acute and subacute models. In this paper, various fractions of ethanol extract of Stereospermum suaveolens were prepared and their effects on blood glucose levels in STZ-induced diabetic rats were studied after a single oral administration (200?mg/kg). Administration of the ethyl acetate fraction at 200?mg/kg once daily for 14 days to STZ-induced diabetic rats was also carried out. The parameters such as the fasting blood glucose, hepatic glycogen content, and pancreatic antioxidant levels were monitored. In the acute study, the ethyl acetate fraction is the most potent in reducing the fasting serum glucose levels of the STZ-induced diabetic rats. The 14-day repeated oral administration of the ethyl acetate fraction significantly reduced the fasting blood glucose and pancreatic TBARS level and significantly increased the liver glycogen, pancreatic superoxide dismutase, and catalase activities as well as reduced glutathione levels. The histopathological studies during the subacute treatment have been shown to ameliorate the STZ-induced histological damage of pancreas. This paper concludes that the ethyl acetate fraction from ethanol extract of Stereospermum suaveolens possesses potent antihyperglycemic and antioxidant properties, thereby substantiating the use of plant in the indigenous system of medicine. PMID:22593683

  9. Nesfatin-1 stimulates fatty-acid oxidation by activating AMP-activated protein kinase in STZ-induced type 2 diabetic mice.

    PubMed

    Dong, Jing; Xu, Huan; Xu, Huan; Wang, Peng-fei; Cai, Gui-ju; Song, Hai-feng; Wang, Chang-chen; Dong, Zhao-tong; Ju, Yan-jiao; Jiang, Zheng-yao

    2013-01-01

    Nesfatin-1 is an anorexigenic peptide involved in energy homeostasis. Recently, nesfatin-1 was reported to decrease blood glucose level and improve insulin sensitivity in high-fat diet-fed rats. However, little information is known about the influence of nesfatin-1 on lipid metabolism either in physiological or diabetic condition. This study undertook whether nesfatin-1 was involved in the pathophysiology in Streptozotocin-induced type 2 diabetic mice (T2DM), which was induced by a combination of high-calorie diet and two low-doses Streptozotocin. We observed that plasma nesfatin-1 was significantly increased while expression of nesfatin-1 neurons were decreased in hypothalamus in diabetes group compared to only high-calorie diet control group; intravenous injection of nesfatin-1 decreased 0-1h, 0-2h, 0-3h cumulative food intake in T2DM, but 0-24h total food intake had no difference between groups. Body weight and plasma FFA were normalized after nesfatin-1(10 g/Kg) administration for 6 days. These results suggested that nesfatin-1 improved lipid disorder in T2DM. It was found that blood glucose and insulin resistance coefficient decreased with treatment of nesfatin-1 (both in 1 g/Kg and 10 g/Kg doses) in diabetes mice. For further understanding the role of nesfatin-1 on lipid metabolism, we detected p-AMPK and p-ACC of skeletal muscle in T2DM using western blotting. The expression of p-AMPK and p-ACC increased when nesfatin-1 was given with doses 1 g/Kg but not in doses 10 g/Kg. Taken together, nesfatin-1 participated in the development of T2DM and stimulated free fatty acid utilization via AMPK-ACC pathway in skeletal muscle in T2DM. PMID:24391760

  10. Hypotriglyceridemic and hypocholesterolemic effects of anti-diabetic Momordica charantia (karela) fruit extract in streptozotocin-induced diabetic rats.

    PubMed

    Ahmed, I; Lakhani, M S; Gillett, M; John, A; Raza, H

    2001-03-01

    Momordica charantia (karela) is commonly used as an antidiabetic and antihyperglycemic agent in Asian, Oriental and Latin American countries. This study was undertaken to investigate the effects of long term feeding (10 weeks) of M. charantia fruit extract on blood plasma and tissue lipid profiles in normal and streptozotocin (STZ)-induced Type 1 diabetic rats. The results show that there was a significant (P < 0.05) increase in plasma non-esterified cholesterol, triglycerides and phospholipids in STZ-induced diabetic rats, accompanied by a decrease in high density lipoprotein (HDL)-cholesterol. A moderate increase in plasma (LPO) product, malonedialdehyde (MDA), and about two-fold increase in kidney LPO was also observed in STZ-induced diabetic rats. The treatment of diabetic rats with M. charantia fruit extract over a 10-week period returned these levels close to normal. In addition, karela juice also exhibited an inhibitory effect on membrane LPO under in vitro conditions. These results suggest that M. charantia fruit extract exhibits hypolipidemic as well as hypoglycemic effects in the STZ-induced diabetic rat. PMID:11269887

  11. Attenuation of erythrocyte membrane oxidative stress by Sesbania grandiflora in streptozotocin-induced diabetic rats.

    PubMed

    Sureka, Chandrabose; Ramesh, Thiyagarajan; Begum, Vavamohaideen Hazeena

    2015-08-01

    The aim of the present study was to investigate the protective effects of Sesbania grandiflora flower (SGF) extract on erythrocyte membrane in Streptozotocin (STZ)-induced diabetic rats. Adult male albino rats of Wistar strain, weighing 190-220 g, were made diabetic by an intraperitonial administration of STZ (45 mg/kg). Normal and diabetic rats were treated with SGF, and diabetic rats were also treated with glibenclamide as drug control, for 45 days. In this study plasma insulin and haemoglobin levels were decreased and blood glucose, glycosylated haemoglobin, protein oxidation, lipid peroxidation markers, and osmotic fragility levels were increased in diabetic rats. Moreover, erythrocytes antioxidant enzymes such as superoxide dismutase, catalase, glutathione peroxide, glutathione reductase, glutathione-S-transferase, and glucose-6-phosphate dehydrogenase activities and non-enzymatic antioxidants such as vitamin C, vitamin E, reduced glutathione (GSH), and oxidized glutathione (GSSG) levels were altered. Similarly, the activities of total ATPases, Na(+)/K(+)-ATPase, Ca(2+)-ATPase, and Mg(2+)-ATPase were also decreased in the erythrocytes of diabetic rats. Administration of SGF to STZ-induced diabetic rats reduced blood glucose and glycosylated haemoglobin levels with increased levels of insulin and haemoglobin. Moreover, SGF reversed the protein and lipid peroxidation markers, osmotic fragility, membrane-bound ATPases activities, and antioxidant status in STZ-induced diabetic rats. These results suggest that SGF could provide a protective effect on diabetes by decreasing oxidative stress-associated diabetic complications. PMID:26176361

  12. Antihyperglycemic and Antihyperlipidemic Effects of Fruit Aqueous Extract of Berberis integerrima Bge. in Streptozotocin-induced Diabetic Rats

    PubMed Central

    Ashraf, Hossein; Heidari, Reza; Nejati, Vahid

    2014-01-01

    Use of medicinal plants for attenuation of hyperglycemia and restoration of lipids disorder to normal level is clinically very important. The aim of present study was to evaluate the effects of Berberis integerrima Bge. fruit aqueous extract (BIFAE) on blood glucose and lipid profile in streptozotocin (STZ) - induced diabetic rats. The STZ-induced diabetic rats were treated by fruit aqueous extract of Berberis integerrima Bge. at doses (250 and 500 mg/Kg bw) and glibenclamide (0.6 mg/Kg bw) for 42 days by gavage. Blood glucose levels and body weights of rats were measured on weeks 0, 2, 4 and 6. Total lipid levels were determined in normal and STZ-induced diabetic rats after administration of the BIFAE and glibenclamide for 42 days. STZ-induced diabetic rats showed a significant (P<0.001) increases in the levels of blood glucose, triglycerides (TG), total cholesterol (TC), low density lipoprotein LDL-cholesterol (LDL-C) while body weight and high density lipoprotein HDL-cholesterolan (HDL-C) were significantly(P<0.001) decreased compared to normal rats. Daily administration of BIFAE did not possess the hypoglycemic and hypolipidaemic activity in STZ- diabetic rats during 6-week treatment period. Results indicate the usage of BIFAE in traditional medicine for the treatment of diabetes may need more investigation. PMID:25587320

  13. Anti-diabetic, anti-hyperlipidemic and spermatogenic effects of Amaranthus spinosus Linn. on streptozotocin-induced diabetic rats.

    PubMed

    Sangameswaran, B; Jayakar, B

    2008-01-01

    Anti-diabetic, anti-hyperlipidemic and spermatogenic effects were studies with methanolic extract of stem of Amaranthus spinosus Linn (Family: Amaranthaceae) in diabetic rats. In streptozotocin (STZ)-induced diabetic rats, it was observed that both the standard drug (Glibenclamide) and methanolic extract of Amaranthus spinosus Linn. significantly exhibited control of blood glucose level on a 15 day model. Further, the methanolic extract also showed significant anti-hyperlipidemic and spermatogenic effects in STZ-induced diabetic rats. The methanolic extract has also accelerated the process of spermatogenesis by increasing the sperm count and accessory sex organ weights. The present investigation of the plant established some pharmacological evidence to support the folklore claim that it is used as an anti-diabetic. PMID:18404348

  14. AB150. Dietary resistant maltodextrin ameliorates testicular function and spermatogenesis in streptozotocin-induced diabetic rats

    PubMed Central

    Tsao, Chih-Wei; Liu, Chin-Yu; Cha, Tai-Lung

    2015-01-01

    Objective This study investigated the effect of resistant maltodextrin (RMD) on reproduction in streptozotocin (STZ)-induced type 2 diabetic male rats. Methods Forty male rats were induced with diabetes by a single intraperitoneal injection of STZ (50 mg/kg) and nicotinamide (100 mg/kg). Five groups were analyzed in total: normal, Diabetic rats without RMD, diabetic rats with RMD 1.2 g/100 g diet (1), with RMD 2.4 g/100 g (2), and with RMD 6.0 g/100 g (5). Results The groups of diabetic rats with the RMD supplement, compared to those without supplement, showed improved plasma glucose control, attenuated insulin resistance and recovery of testosterone level & spermatogenesis stage. The STZ-induced diabetes mellitus (DM) caused a significant reduction in serum testosterone, testis androgen receptor (AR), steroidogenic acute regulatory protein (StAR) and 3?-hydroxysteroid dehydrogenase (3?-HSD) protein, but a statistical recovery in each of these was observed in the 5 group. TUNEL-positive cells were observed in the Diabetic without RMD group and RMD treatment reduced apoptotic germ cells. The expression of Bax/Bcl2 was induced in the diabetic group and also significantly reduced in the 5 group. Conclusions Dietary RMD may improve metabolic control in STZ-induced diabetic rats and attenuate hyperglycemia-related impaired male reproduction and testicular function.

  15. Heme Oxygenase-1 Promotes Delayed Wound Healing in Diabetic Rats

    PubMed Central

    Chen, Qing-Ying; Wang, Guo-Guang; Li, Wei; Jiang, Yu-Xin; Lu, Xiao-Hua; Zhou, Ping-Ping

    2016-01-01

    Diabetic ulcers are one of the most serious and costly chronic complications for diabetic patients. Hyperglycemia-induced oxidative stress may play an important role in diabetes and its complications. The aim of the study was to explore the effect of heme oxygenase-1 on wound closure in diabetic rats. Diabetic wound model was prepared by making an incision with full thickness in STZ-induced diabetic rats. Wounds from diabetic rats were treated with 10% hemin ointment for 21 days. Increase of HO-1 protein expression enhanced anti-inflammation and antioxidant in diabetic rats. Furthermore, HO-1 increased the levels of VEGF and ICAM-1 and expressions of CBS and CSE protein. In summary, HO-1 promoted the wound closure by augmenting anti-inflammation, antioxidant, and angiogenesis in diabetic rats. PMID:26798657

  16. Combination therapies prevent the neuropathic, proinflammatory characteristics of bone marrow in streptozotocin-induced diabetic rats.

    PubMed

    Dominguez, James M; Yorek, Mark A; Grant, Maria B

    2015-02-01

    We previously showed that peripheral neuropathy of the bone marrow was associated with loss of circadian rhythmicity of stem/progenitor cell release into the circulation. Bone marrow neuropathy results in dramatic changes in hematopoiesis that lead to microvascular complications, inflammation, and reduced endothelial repair. This series of events represents early pathogenesis before development of diabetic retinopathy. In this study we characterized early alterations within the bone marrow of streptozotocin (STZ)-induced diabetic rats following treatments that prevent experimental peripheral neuropathy. We asked whether bone marrow neuropathy and the associated bone marrow pathology were reversed with treatments that prevent peripheral neuropathy. Three strategies were tested: inhibition of neutral endopeptidase, inhibition of aldose reductase plus lipoic acid supplementation, and insulin therapy with antioxidants. All strategies prevented loss of nerve conduction velocity resulting from STZ-induced diabetes and corrected the STZ-induced diabetes-associated increase of immunoreactivity of neuropeptide Y, tyrosine hydroxylase, and somatostatin. The treatments also reduced concentrations of interleukin-1?, granulocyte colony-stimulating factor, and matrix metalloproteinase 2 in STZ-induced diabetic bone marrow supernatant and decreased the expression of NADPH oxidase 2, nitric oxide synthase 2, and nuclear factor-?B1 mRNA in bone marrow progenitor cells. These therapies represent novel approaches to attenuate the diabetic phenotype within the bone marrow and may constitute an important therapeutic strategy for diabetic microvascular complications. PMID:25204979

  17. Metabolomic analysis of rat serum in streptozotocin-induced diabetes and after treatment with oral triethylenetetramine (TETA)

    PubMed Central

    2012-01-01

    Background The prevalence, and associated healthcare burden, of diabetes mellitus is increasing worldwide. Mortality and morbidity are associated with diabetic complications in multiple organs and tissues, including the eye, kidney and cardiovascular system, and new therapeutics to treat these complications are required urgently. Triethylenetetramine (TETA) is one such experimental therapeutic that acts to chelate excess copper (II) in diabetic tissues and reduce oxidative stress and cellular damage. Methods Here we have performed two independent metabolomic studies of serum to assess the suitability of the streptozotocin (STZ)-induced rat model for studying diabetes and to define metabolite-related changes associated with TETA treatment. Ultraperformance liquid chromatography-mass spectrometry studies of serum from non-diabetic/untreated, non-diabetic/TETA-treated, STZ-induced diabetic/untreated and STZ-induced diabetic/TETA-treated rats were performed followed by univariate and multivariate analysis of data. Results Multiple metabolic changes related to STZ-induced diabetes, some of which have been reported previously in other animal and human studies, were observed, including changes in amino acid, fatty acid, glycerophospholipid and bile acid metabolism. Correlation analysis suggested that treatment with TETA led to a reversal of diabetes-associated changes in bile acid, fatty acid, steroid, sphingolipid and glycerophospholipid metabolism and proteolysis. Conclusions Metabolomic studies have shown that the STZ-induced rat model of diabetes is an appropriate model system to undertake research into diabetes and potential therapies as several metabolic changes observed in humans and other animal models were also observed in this study. Metabolomics has also identified several biological processes and metabolic pathways implicated in diabetic complications and reversed following treatment with the experimental therapeutic TETA. PMID:22546713

  18. Extract of Rhizoma Polygonum cuspidatum reduces early renal podocyte injury in streptozotocin-induced diabetic rats and its active compound emodin inhibits methylglyoxal-mediated glycation of proteins

    PubMed Central

    SOHN, EUNJIN; KIM, JUNGHYUN; KIM, CHAN SIK; JO, KYUHYUNG; KIM, JIN SOOK

    2015-01-01

    Podocyte injury contributes to renal damage and, eventually, to the occurrence of proteinuria in diabetic nephropathy. The aim of the present study was to investigate the effect of an ethanol extract from Rhizoma Polygonum cuspidatum (P. cuspidatum) on proteinuria and podocyte injury, and elucidate the underlying mechanism for streptozotocin (STZ)-induced diabetic nephropathy. The protective effects of P. cuspidatum extract (PCE) on renal podocytes in STZ-induced diabetic rats were also investigated. PCE (100 or 350 mg/kg/day) was administered to STZ-induced diabetic rats for 16 weeks, and blood glucose levels, body weight and proteinuria were measured. A double labeling technique with the terminal deoxynucleotidyl transferase dUTP nick end labeling assay was performed and synaptopodin expression was observed. In addition, cleaved caspase-3, methylglyoxal (MGO) and 8-hydroxydeoxyguanosine (8-OHdG) expression levels were measured. STZ-induced diabetic rats developed hyperglycemia and proteinuria. Increased apoptosis of the podocytes and increased cleaved caspase-3, MGO and 8-OHdG expression levels, as well as decreased synaptopodin expression were detected in the glomeruli of STZ-induced diabetic rats. However, treatment with PCE for 16 weeks restored protein levels to normal, and reduced podocyte loss and apoptosis. Levels of caspase-3 and MGO expression, as well as oxidative stress were ameliorated by PCE treatment. In addition, emodin, a biologically active ingredient of PCE, exerted an MGO scavenging effect and inhibited MGO-derived advanced glycation end-product formation. These findings indicate that PCE may be administered to prevent proteinuria and podocyte loss in STZ-induced diabetic rats partly by inhibiting podocyte apoptosis and cleaved caspase-3 expression, and by restoring the balance of oxidative stress and MGO expression. PMID:26299942

  19. Extract of Rhizoma Polygonum cuspidatum reduces early renal podocyte injury in streptozotocin?induced diabetic rats and its active compound emodin inhibits methylglyoxal?mediated glycation of proteins.

    PubMed

    Sohn, Eunjin; Kim, Junghyun; Kim, Chan Sik; Jo, Kyuhyung; Kim, Jin Sook

    2015-10-01

    Podocyte injury contributes to renal damage and, eventually, to the occurrence of proteinuria in diabetic nephropathy. The aim of the present study was to investigate the effect of an ethanol extract from Rhizoma Polygonum cuspidatum (P. cuspidatum) on proteinuria and podocyte injury, and elucidate the underlying mechanism for streptozotocin (STZ)?induced diabetic nephropathy. The protective effects of P. cuspidatum extract (PCE) on renal podocytes in STZ?induced diabetic rats were also investigated. PCE (100 or 350 mg/kg/day) was administered to STZ?induced diabetic rats for 16 weeks, and blood glucose levels, body weight and proteinuria were measured. A double labeling technique with the terminal deoxynucleotidyl transferase dUTP nick end labeling assay was performed and synaptopodin expression was observed. In addition, cleaved caspase?3, methylglyoxal (MGO) and 8?hydroxydeoxyguanosine (8?OHdG) expression levels were measured. STZ?induced diabetic rats developed hyperglycemia and proteinuria. Increased apoptosis of the podocytes and increased cleaved caspase?3, MGO and 8?OHdG expression levels, as well as decreased synaptopodin expression were detected in the glomeruli of STZ?induced diabetic rats. However, treatment with PCE for 16 weeks restored protein levels to normal, and reduced podocyte loss and apoptosis. Levels of caspase?3 and MGO expression, as well as oxidative stress were ameliorated by PCE treatment. In addition, emodin, a biologically active ingredient of PCE, exerted an MGO scavenging effect and inhibited MGO?derived advanced glycation end?product formation. These findings indicate that PCE may be administered to prevent proteinuria and podocyte loss in STZ?induced diabetic rats partly by inhibiting podocyte apoptosis and cleaved caspase?3 expression, and by restoring the balance of oxidative stress and MGO expression. PMID:26299942

  20. Hypoglycemic effect of the water extract of Smallantus sonchifolius (yacon) leaves in normal and diabetic rats.

    PubMed

    Aybar, M J; Snchez Riera, A N; Grau, A; Snchez, S S

    2001-02-01

    The hypoglycemic effect of the water extract of the leaves of Smallantus sonchifolius (yacon) was examined in normal, transiently hyperglycemic and streptozotocin (STZ)-induced diabetic rats. Ten-percent yacon decoction produced a significant decrease in plasma glucose levels in normal rats when administered by intraperitoneal injection or gastric tube. In a glucose tolerance test, a single administration of 10% yacon decoction lowered the plasma glucose levels in normal rats. In contrast, a single oral or intraperitoneal administration of yacon decoction produced no effect on the plasma glucose levels of STZ-induced diabetic rats. However, the administration of 2% yacon tea ad libitum instead of water for 30 days produced a significant hypoglycemic effect on STZ-induced diabetic rats. After 30 days of tea administration, diabetic rats showed improved body (plasma glucose, plasma insulin levels, body weight) and renal parameters (kidney weight, kidney to body weight ratio, creatinine clearance, urinary albumin excretion) in comparison with the diabetic controls. Our results suggest that yacon water extract produces an increase in plasma insulin concentration. PMID:11167030

  1. Evaluation of antioxidants in the kidney of streptozotocin induced diabetic rats.

    PubMed

    Gomathi, D; Kalaiselvi, M; Ravikumar, G; Devaki, K; Uma, C

    2014-04-01

    Diabetes mellitus is one of the most common endocrine metabolic disorders. Dual endocrine deficits of impaired insulin action (insulin resistance) and inadequate insulin secretion create an environment of chronic hyperglycemia and general metabolic disarray. Oxidative stress plays an important role in diabetic pathogenesis. Oxidative stress induced by streptozotocin (STZ) has been shown to damage pancreatic beta cell and produce hyperglycemia in rats. The present study was made to evaluate the antioxidant activity of ethanolic extract of the Evolvulus alsinoides in STZ induced rats. The antioxidant activities were done by using standard protocols. For histopathological analysis, the pancreatic tissues of all experimental groups were fixed with 10% formalin for 24h then the samples were stained with hematoxylin-eosin for the microscopic observation. Our results showed the significant decrease in lipid peroxidation and increases in the antioxidant (both enzymatic and nonenzymatic) levels after treatment with standard as well as the E. alsinoides. There is no significant difference between control and plant alone group rats. The histopathology reports also revealed non-toxic effect and protective effect of E. alsinoides in the kidney of STZ induced diabetic rats. Our result indicated that the E. alsinoides extract effectively increased the antioxidant level thereby it prevents oxidative stress during diabetes mellitus and also it showed the protective effect on kidney of STZ induced rats. Hence it can be used to maintain the antioxidant level during diabetes mellitus. PMID:24757306

  2. Anti-depressant effect of hesperidin in diabetic rats.

    PubMed

    El-Marasy, Salma A; Abdallah, Heba M I; El-Shenawy, Siham M; El-Khatib, Aiman S; El-Shabrawy, Osama A; Kenawy, Sanaa A

    2014-11-01

    This study aimed to investigate the anti-depressant effect of hesperidin (Hsp) in streptozotocin (STZ)-induced diabetic rats. Additionally, the effect of Hsp on hyperglycaemia, oxidative stress, inflammation, brain-derived neurotrophic factor (BDNF), and brain monoamines in diabetic rats was also assessed. The Wistar rats in the experimental groups were rendered hyperglycaemic with a single dose of STZ (52.5 mg(kg body mass)(-1), by intraperitoneal injection). The normal group received the vehicle only. Hyperglycaemic rats were treated with Hsp (25.0, 50.0, or 100.0 mg(kg body mass)(-1)day(-1), per oral) and fluoxetine (Flu) (5.0 mg(kg body mass)(-1)day(-1), per oral) 48 h after the STZ injection, for 21 consecutive days. The normal and STZ control groups received the vehicle (distilled water). Behavioral and biochemical parameters were then assessed. When Hsp was administered to the STZ-treated rats, this reversed the STZ-induced increase in immobility duration in the forced swimming test (FST) and attenuated hyperglycaemia, decreased malondialdehyde (MDA), increased reduced glutathione (GSH) decreased interleukin-6 (IL-6), and increased BDNF levels in the brain. Treatment with Hsp attenuated STZ-induced neurochemical alterations, as indicated by increased levels of monoamines in the brain, namely, norepinephrine (NE), dopamine (DA), and serotonin (5-hydroxytryptamine; 5-HT). All of these effects of Hsp were similar to those observed with the established anti-depressant Flu. This study shows that Hsp exerted anti-depressant effect in diabetic rats, which may have been partly mediated by its amelioration of hyperglycaemia as well as its anti-oxidant and anti-inflammatory activities, the enhancement of neurogenesis, and changes in the levels of monoamines in the brain. PMID:25358020

  3. Beneficial Effect of Leptin on Spatial Learning and Memory in Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Ghasemi, Mohsen; Zendehbad, Bamdad; Zabihi, Hoda; Hosseini, Mahmoud; Hadjzadeh, Mousa Al Reza; Hayatdavoudi, Parichehr

    2016-01-01

    Background: Diabetes mellitus is a chronic disease which may be accompanied by cognitive impairments. The expression of the obesity gene (ob) is decreased in insulin-deficient diabetic animals and increased after the administration of insulin or leptin. Plasma leptin levels are reduced in the streptozotocin (STZ)-induced diabetic rats. Therefore, the deleterious effects of diabetes on memory may be due to the reduction of leptin. Aims: Investigate the effect of subcutaneous injection of leptin on spatial learning and memory in STZ-induced diabetic rats. Study Design: Animal experimentation. Methods: The rats were divided into three groups: 1-control, 2- diabetic, and 3- diabetic-leptin. Diabetes was induced in groups 2 and 3 by STZ injection (55 mg/kg) intraperitoneally (i.p). The animals received leptin (0.1 mg/kg) or saline subcutaneously (s.c) for 10 days before behavioral studies. Then, they were examined in the Morris water maze over 3 blocks after 3 days of the last injection of leptin. Results: The travelled path length and time spent to reach the platform significantly increased in the diabetic group (p<0.001) and decreased with leptin treatment (p<0.01 & p<0.001 respectively); also, a significant increase in path length and time was observed between the diabetic-leptin group and the diabetic group (p<0.01, p<0.001, respectively) in the probe test. Conclusion: Leptin can exert positive effects on memory impairments in diabetic rats. PMID:26966625

  4. Effect of aloe vera leaf gel extract on membrane bound phosphatases and lysosomal hydrolases in rats with streptozotocin diabetes.

    PubMed

    Rajasekaran, S; Sriram, N; Arulselvan, P; Subramanian, S

    2007-03-01

    Diabetes mellitus is known to promote deterioration of membrane function and impair intra cellular metabolism in the organism. The aim of the present study was to examine the effect of the ethanolic extract from Aloe vera leaf gel on membrane bound phosphatases and lysosomal hydrolases in the liver and kidney of streptozotocin (STZ)-induced diabetic rats. The rats treated with STZ showed significant alterations in the activities of membrane bound phosphatases and lysosomal hydrolases in the liver and kidney. Oral administration of Aloe vera gel extract at a dose of 300 mg/kg body weight/day to STZ-induced diabetic rats for a period of 21 days significantly restored the alterations in enzymes activity to near normalcy. These results were compared with glibenclamide, a reference drug. Thus, the present study confirms that Aloe vera gel extract possesses a significant beneficial effect on membrane bound phosphatases and lysosomal hydrolases. PMID:17416200

  5. Effects of pentoxifylline administration on histomorphological parameters of streptozotocin-induced diabetic rat testes

    PubMed Central

    Piryaei, Abbas; Najar, Azam

    2015-01-01

    The effect of pentoxifylline (PTX) administration on histomorphological parameters of streptozotocin (STZ)-induced type 1 diabetes mellitus (DM) in male rat testes were evaluated. We randomly divided 40 male rats into the following four groups: group 1: control or normal glycemic (NG) rats; group 2 or NG rats that received only normal saline (NS), (NG+NS); group 3 or diabetic rats which were not treated by PTX (DM+vehicle solution (NS)); and group 4 which comprised diabetic rats treated with 50 mg/kg of PTX (DM+PTX). Type 1 DM was induced by intraperitoneal injection of STZ (55 mg/kg). Rats were held for 30 days after which the experimental group received PTX twice daily (25 mg/kg) or NS. After 14 days of treatment by PTX or NS, the left testes from all rats were extracted and prpared for histological study. Apoptotic cells, blood vessel density, and spermatogenesis were evaluated. Data were analyzed by ANOVA test. PTX-treated-diabetic rats showed a significant decrease in number of apoptotic cells and decrease in blood vessel density compared to the DM+NS rats. A significant increase in spermatogenesis was observed in the PTX-treated diabetic group, compared to the DM+NS groups. It was concluded that PTX administration to STZ-induced type 1 DM rats affected apoptotic cell number positively. Moreover, blood vessel density significantly decreased and improvements were observed in spermatogenesis. PMID:26472963

  6. An Early Diagnostic Tool for Diabetic Peripheral Neuropathy in Rats

    PubMed Central

    Kambiz, Shoista; van Neck, Johan W.; Cosgun, Saniye G.; van Velzen, Marit H. N.; Janssen, Joop A. M. J. L.; Avazverdi, Naim; Hovius, Steven E. R.; Walbeehm, Erik T.

    2015-01-01

    The skins rewarming rate of diabetic patients is used as a diagnostic tool for early diagnosis of diabetic neuropathy. At present, the relationship between microvascular changes in the skin and diabetic neuropathy is unclear in streptozotocin (STZ) diabetic rats. The aim of this study was to investigate whether the skin rewarming rate in diabetic rats is related to microvascular changes and whether this is accompanied by changes observed in classical diagnostic methods for diabetic peripheral neuropathy. Computer-assisted infrared thermography was used to assess the rewarming rate after cold exposure on the plantar skin of STZ diabetic rats hind paws. Peripheral neuropathy was determined by the density of intra-epidermal nerve fibers (IENFs), mechanical sensitivity, and electrophysiological recordings. Data were obtained in diabetic rats at four, six, and eight weeks after the induction of diabetes and in controls. Four weeks after the induction of diabetes, a delayed rewarming rate, decreased skin blood flow and decreased density of IENFs were observed. However, the mechanical hyposensitivity and decreased motor nerve conduction velocity (MNCV) developed 6 and 8 weeks after the induction of diabetes. Our study shows that the skin rewarming rate is related to microvascular changes in diabetic rats. Moreover, the skin rewarming rate is a non-invasive method that provides more information for an earlier diagnosis of peripheral neuropathy than the classical monofilament test and MNCV in STZ induced diabetic rats. PMID:25984949

  7. Renal effects of plant-derived oleanolic acid in streptozotocin-induced diabetic rats.

    PubMed

    Mapanga, R F; Tufts, M A; Shode, F O; Musabayane, C T

    2009-01-01

    Previous studies from our laboratories indicate that the anti-diabetic effects of Syzygium cordatum (Hochst.) [Myrtaceae] leaf extract in streptozotocin-induced diabetic rats may be attributed in part to mixtures of triterpenes, oleanolic acid (3ss-hydroxy-olea-12-en-28-oic acid, OA) and ursolic acid (3ss -hydroxyl-urs-12-en-28-oic acid, UA). For the bioactive compounds to have potential in diabetes management, they should alleviate or prevent complications of diabetes mellitus, kidney function, and cardiovascular disorders. This study was, therefore, designed to assess whether S. cordatum leaf derived OA influenced renal function evaluated by the ability to increase urinary Na(+) outputs parameters and creatinine clearance (Ccr) of streptozotocin (STZ)-induced diabetic rats. Extraction and fractionation of S. cordatum powdered leaf ethyl acetate-solubles (EAS) yielded mixtures of OA/UA and methyl maslinate/methyl corosolate. Recrystallization of OA/UA mixture using ethanol afforded OA, the structure of which was confirmed by NMR spectroscopy ((1)H & (13)C). Acute effects of OA on kidney function and mean arterial blood pressure (MAP) were investigated in anesthetized rats challenged with hypotonic saline after a 3.5-h equilibration for 4h of 1 h control, 1.5 h treatment, and 1.5 h recovery periods. OA was added to the infusate during the treatment period. Chronic effects of OA were studied in individually caged rats treated twice daily with OA (60 mg/kg, p.o.) for five weeks. By comparison with respective control animals administration, OA significantly increased Na(+) excretion rates of non-diabetic and STZ-induced diabetic rats without affecting urine flow, K(+) and Cl(-) rates. At the end of five weeks, OA treatment significantly (p < 0.05) increased Ccr in non-diabetic (2.88 +/- 0.14 vs. 3.71 +/- 0.30 ml/min) and STZ-diabetic rats (1.81 +/- 0.32 vs. 3.07 +/- 0.16 ml/min) with concomitant reduction of plasma creatinine concentration (n = 6 in all groups). OA also caused significant decreases in MAP in non-diabetic and STZ-induced diabetic rats. These findings suggest that OA may have beneficial effects on some processes associated with renal derangement of STZ-induced diabetic rats. PMID:19839826

  8. Anti-diabetic activity of methanolic extract of Alpinia galanga Linn. aerial parts in streptozotocin induced diabetic rats

    PubMed Central

    Verma, Ramesh Kumar; Mishra, Garima; Singh, Pradeep; Jha, Keshri K.; Khosa, Ratan L.

    2015-01-01

    Introduction: Alpinia galanga Linn. belongs to the family Zingiberaceae has been used as a traditional medicine in China for relieving stomach ache, treating cold, invigorating the circulatory systems, diabetes, and reducing swelling. Aim: To evaluate the antidiabetic activity of methanolic extract of A. galanga aerial parts on streptozotocin (STZ) induced diabetic rats. Materials and Methods: Diabetes was induced by single intraperitoneal injection of STZ at a dose of 60 mg/kg bodyweight. Test drug methanolic extract of A. galanga (200 and 400 mg/kg b.w.) and glibenclamide (10 mg/kg b.w.) as standard drug was administered orally for 21 consecutive days in STZ-induced diabetic rats. Fasting blood glucose level, serum lipid profiles, as well as initial and final changes in body weight were assessed along with histopathology. All the parameters were statistically analyzed by using one-way ANOVA followed by Bonferroni t-test. Results: Experimental findings showed significant dose dependent antidiabetic potential of methanolic extract in terms of reduction of fasting blood glucose level and various biochemical parameters in diabetic rats when compared with that of the diabetic control group, which might be due to the stimulatory effect of methanolic extracts on the regenerating β-cells and also on the surviving β-cells. Conclusion: Methanolic extract of aerial parts of A. galanga was effective in controlling blood glucose level and improve lipid profile in euglycemic as well as diabetic rats. PMID:26730146

  9. Endoplasmic reticulum stress is involved in myocardial apoptosis of streptozocin-induced diabetic rats.

    PubMed

    Li, Zhenhua; Zhang, Tao; Dai, Hongyan; Liu, Guanghui; Wang, Haibin; Sun, Yingying; Zhang, Yun; Ge, Zhiming

    2008-03-01

    Apoptosis plays a critical role in the diabetic cardiomyopathy, and endoplasmic reticulum stress (ERS) is one of the intrinsic apoptosis pathways. Previous studies have shown that the endoplasmic reticulum becomes swollen and dilated in diabetic myocardium, and ERS is involved in heart failure and diabetic kidney. This study is aimed to demonstrate whether ERS is induced in myocardium of streptozotocin (STZ)-induced diabetic rats. We established a type 1 diabetic rat model, used echocardiographic evaluation, hematoxylin-eosin staining, and the terminal deoxynucleotidyl transferase-mediated DNA nick-end labeling staining to identify the existence of diabetic cardiomyopathy and enhanced apoptosis in the diabetic heart. We performed immunohistochemistry, western blot, and real-time PCR to analyze the hallmarks of ERS that include glucose-regulated protein 78, CCAAT/enhancer-binding protein homologous protein (CHOP) and caspase12. We found these hallmarks to have enhanced expression in protein and mRNA levels in diabetic myocardium. Also, another pathway that can lead to cell death of ERS, c-Jun NH(2)-terminal kinase-dependent pathway, was also activated in diabetic heart. Those results suggested that ERS was induced in STZ-induced diabetic rats' myocardium, and ERS-associated apoptosis occurred in the pathophysiology of diabetic cardiomyopathy. PMID:18310452

  10. Icariside II ameliorates diabetic nephropathy in streptozotocin-induced diabetic rats

    PubMed Central

    Tian, Wenjie; Lei, Hongen; Guan, Ruili; Xu, Yongde; Li, Huixi; Wang, Lin; Yang, Bicheng; Gao, Zhezhu; Xin, Zhongcheng

    2015-01-01

    Purpose To investigate the therapeutic effects and potential mechanisms of icariside II (ICA II) on reversing diabetic nephropathy in streptozotocin (STZ)-induced type I diabetic rats. Methods Newborn male Sprague Dawley rats were labeled with thymidine analog 5-ethynyl-2-deoxyuridine (EdU) for tracking endogenous label retaining progenitor cells (LRCs). At age of 8 weeks, 48 rats were randomly divided into three groups: normal control group (n=16), diabetes mellitus group (DM; n=16), and diabetes mellitus plus ICA II therapy group (DM+ICA II, n=16). Eight weeks induced for diabetes with STZ, rats in DM group and DM+ICA II group were treated with vehicle or ICA II (5 mg/kg/day) for another 8 weeks, respectively. Then, blood creatinine, 24-hour urine protein, blood urea nitrogen, and glycosylated hemoglobin were measured, as well as the expression of von Willebrand factor, malondialdehyde, transforming growth factor-?/drosophila mothers against decapentaplegic protein/connective tissue growth factor (TGF-?/Smad/CTGF) signaling, marker of proliferation Ki-67, and EdU+ LRCs in renal tissues. Results Increased levels of creatinine, 24-hour urine protein, and blood urea nitrogen and remarkably decreased proportion of normal glomeruli and increased proportions of I, IIa, IIb, and III glomeruli were observed in diabetic rats, while ICA II could reverse these changes. Interestingly, ICA II could significantly downregulate the levels of malondialdehyde and TGF-?/Smad/CTGF signaling and increase the expression of von Willebrand factor, Ki-67, and EdU+ LRCs in the kidney. Conclusion ICA II treatment could ameliorate diabetic nephropathy in STZ-induced diabetic rats by increasing endothelial cell contents, downregulating TGF-?/Smad/CTGF signaling pathway and oxidative stress level, and promoting cell proliferation both in kidney cortex and medulla. These beneficial effects appear to be mediated by its antioxidant capacity and recruitment of endogenous EdU+ progenitor cells into the kidney tissue. PMID:26379427

  11. Effect of Antisense TGF-?1 Oligodeoxynucleotides in Streptozotocin-Induced Diabetic Rat Kidney

    PubMed Central

    Jeong, Hyo Soon; Kim, Sang Pyo; Choi, In Jang; Lee, In Kyu; Kim, Hyun Chul

    2004-01-01

    Transforming growth factor (TGF)-?1 is an important fibrogenic factor that is involved in the pathogenesis of diabetic nephropathy. We evaluated the effect of circular antisense TGF-?1 oligodeoxynucleotides (ODNs) on the TGF-?1 expression in the rat mesangial cell culture and in streptozotocin (STZ)-induced diabetic rats. Circular antisense TGF-?1 ODNs were found to be stable in rat serum, significantly decreasing TGF-?1 mRNA expression compared with linear antisense ODNs in the rat mesangial cell culture. Circular antisense TGF-?1 ODNs were introduced into the tail vein of normal rats using hemagglutinating virus of Japan (HVJ)-liposome-mediated gene transfer method and were confirmed to be delivered effectively into the kidney, liver, lungs, and spleen. To inhibit the overexpression of TGF-?1 in diabetic kidneys, we introduced circular antisense TGF-?1 ODNs into the STZ-induced diabetic rats. On day 13 after circular antisense TGF-?1 ODNs injection, TGF-?1 mRNA and protein expression markedly decreased and urinary TGF-?1 excretion rate also dropped in the circular antisense TGF-?1 ODNs-treated diabetic rats. These results suggest that circular antisense TGF-?1 ODNs may be a useful tool for developing new therapeutic application for progressive diabetic nephropathy. PMID:15201503

  12. Diabetes alters the blood glucose response to ketamine in streptozotocin-diabetic rats

    PubMed Central

    Chen, Huayong; Li, Li; Xia, Hui

    2015-01-01

    Ketamine is a commonly used short-acting anesthetic and recently attempted to treat pain which is a complication of diabetes. In this study we investigated the effect of ketamine on glucose levels of normal rats and diabetic rats. The results showed that no significance between the glucose levels in ketamine treatment group and saline treatment group at all time points was observed in normal rats. Ketamine did not produce hyperglycemia in normal fasted rats. However, ketamine dose dependently elevated glucose in diabetic rats from 80 mg/kg to 120 mg/kg at 1 hour after injection. The glucose did not return to the levels before treatment in streptozotocin (STZ) induced diabetic rats. Insulin revealed a powerful potency in decreasing glucose levels in diabetic rats. Ketamine did not induce acute hyperglycemia any more after diabetic rats pretreated with insulin. Serum corticosterone was significantly increased in all treatment groups including saline group after 1 hour treatment compared with baseline values. Then the corticosterone declined in both saline treatment groups. However, ketamine induced a more significant increase in corticosterone at 1 hour after injection compared with that of saline control group of diabetic rats. And no decline trend of corticosterone was observed after ketamine treatment 2 hours. Insulin did not reduce the elevated corticosterone level induced by ketamine either. The results suggested that the diabetic rats had a risk of hyperglycaemia when they were treated with ketamine. Pretreatment with insulin is a good symptomatic treatment for hyperglycaemia induced by ketamine. PMID:26379948

  13. Hypoglycemic and hepatoprotective activity of Rosmarinus officinalis extract in diabetic rats.

    PubMed

    Ramadan, Kholoud S; Khalil, Olfat A; Danial, Enas N; Alnahdi, Hanan S; Ayaz, Najla O

    2013-12-01

    The present study examined the effect of water extract (200 mg/kg body weight) of Rosmarinus officinalis L. in streptozotocin (STZ)-induced diabetic rats for 21 days. The hepatoprotective effects were investigated in the liver tissues sections. There was a significant increase in serum liver biochemical parameters (aspartate aminotransferase, alanine transaminase, and alkaline phosphatase), accompanied by a significant decrease in the level of total protein and albumin in the STZ-induced rats when compared with that of the normal group. The high-dose treatment group (200 mg/kg body wt) significantly restored the elevated liver function enzymes near to normal. This study revealed that rosemary extracts exerted a hepatoprotective effect. The results indicate that the extract exhibits the protective effect on tissues and prove its potentials as an antidiabetic agent. PMID:23625639

  14. Impaired mitochondrial respiratory functions and oxidative stress in streptozotocin-induced diabetic rats.

    PubMed

    Raza, Haider; Prabu, Subbuswamy K; John, Annie; Avadhani, Narayan G

    2011-01-01

    We have previously shown a tissue-specific increase in oxidative stress in the early stages of streptozotocin (STZ)-induced diabetic rats. In this study, we investigated oxidative stress-related long-term complications and mitochondrial dysfunctions in the different tissues of STZ-induced diabetic rats (>15 mM blood glucose for 8 weeks). These animals showed a persistent increase in reactive oxygen and nitrogen species (ROS and RNS, respectively) production. Oxidative protein carbonylation was also increased with the maximum effect observed in the pancreas of diabetic rats. The activities of mitochondrial respiratory enzymes ubiquinol: cytochrome c oxidoreductase (Complex III) and cytochrome c oxidase (Complex IV) were significantly decreased while that of NADH:ubiquinone oxidoreductase (Complex I) and succinate:ubiquinone oxidoreductase (Complex II) were moderately increased in diabetic rats, which was confirmed by the increased expression of the 70 kDa Complex II sub-unit. Mitochondrial matrix aconitase, a ROS sensitive enzyme, was markedly inhibited in the diabetic rat tissues. Increased expression of oxidative stress marker proteins Hsp-70 and HO-1 was also observed along with increased expression of nitric oxide synthase. These results suggest that mitochondrial respiratory complexes may play a critical role in ROS/RNS homeostasis and oxidative stress related changes in type 1 diabetes and may have implications in the etiology of diabetes and its complications. PMID:21686174

  15. Changes in Oxidative Stress and Antioxidant Enzyme Activities in Streptozotocin-Induced Diabetes Mellitus in Rats: Role of Alhagi maurorum Extracts

    PubMed Central

    Sheweita, S. A.; Mashaly, S.; Newairy, A. A.; Abdou, H. M.; Eweda, S. M.

    2016-01-01

    Alhagi maurorum (camel thorn plant) is a promising medicinal plant due to the presence of flavonoids and phenolic compounds as major contents of its constituents. No previous study has been conducted before on A. maurorum extracts as an antioxidative stress and/or antidiabetic herb in STZ-induced DM in rats. Therefore, four groups of rats were allocated as control (C), STZ-induced DM (D), and STZ-induced DM supplemented with 300 mg/kg BW of either aqueous extract (WE) or ethanolic extract (EE) of A. maurorum. The plasma levels of glucose, TG, TC, LDL-C and VLDL-C, MDA, and bilirubin and the activities of transaminases and GR were significantly increased in the diabetic group. Also, diabetic rats showed severe glucose intolerance and histopathological changes in their livers. In addition, levels of insulin, total proteins, GSH, and HDL-C and the activities of SOD, GPx, and GST were significantly decreased in the diabetic rats compared to those of the control group. The ingestion of A. maurorum extracts lowered the blood glucose levels during the OGTT compared to the diabetic rats and restored all tested parameters to their normal levels with the exception of insulin level that could not be restored. It is concluded that A. maurorum extracts decreased elevated blood glucose levels and hyperlipidemia and suppressed oxidative stress caused by diabetes mellitus in rats. PMID:26885249

  16. Resveratrol Ameliorates the Components of Hepatic Inflammation and Apoptosis in a Rat Model of Streptozotocin-Induced Diabetes.

    PubMed

    Pektaş, Mehmet Bilgehan; Sadi, Gökhan; Koca, Halit Bugra; Yuksel, Yasemin; Vurmaz, Ayhan; Koca, Tulay; Tosun, Murat

    2016-02-01

    Preclinical Research Trans-resveratrol has a wide range of biological effects that reflect its antioxidant, anti-inflammatory, anticarcinogenic and cardioprotective properties. This study was conducted to elucidate the potential role of resveratrol on hepatic inflammation and the apoptotic pathway components Bcl-2, Bax and p53 in a streptozotocin (STZ)-induced rat model of diabetes mellitus. Inflammatory and apoptotic biomarkers indicated a reduction in hepatic erythropoietin (1.26-fold) and increased asymmetric dimethylarginine (3.9-fold), visfatin (1.6-fold), inflammatory interleukins and TNF-α contents (approximately twofold each) in the diabetic animals. Induction of inducible nitric oxide synthase gene (2.04-fold) and protein expression (1.24-fold) was also observed. Immunohistochemical studies showed enhancement of the apoptotic biomarkers Bax and p53 in diabetic animals. STZ-induced diabetic male Wistar rats were treated with resveratrol (20 mg/kg/day i.p.). Resveratrol succeeded to recover most of these inflammatory and apoptotic elements. Therefore, inflammatory and apoptotic pathways were proved to be affected by STZ-induced diabetes in several aspects and resveratrol might contribute hepatoprotective effects as evidenced from this study. Drug Dev Res 77 : 12-19, 2016. © 2016 Wiley Periodicals, Inc. PMID:26748675

  17. Improved glycemic control, pancreas protective and hepatoprotective effect by traditional poly-herbal formulation Qurs Tabasheer in streptozotocin induced diabetic rats

    PubMed Central

    2013-01-01

    Background The present study was undertaken to evaluate the antihyperglycemic, antihyperlipidemic and hepatoprotective effect of a traditional unani formulation Qurs Tabasheer in streptozotocin (STZ) induced diabetic wistar rats. Up till now no study was undertaken to appraise the efficacy of Qurs Tabasheer in the diabetic rats. Qurs Tabasheer is a unani formulation restraining preparations from five various herbs namely Tukhme Khurfa (Portulaca oleracea seed), Gule Surkh (Rosa damascena flower), Gulnar (Punica granatum flower), Tabasheer (Bambusa arundinasia dried exudate on node), Tukhme Kahu (Lactuca sativa Linn seed). Methods Effect of Qurs Tabasheer was assessed in STZ (60 mg/kg, i.p single shot) induced diabetic wistar rats. STZ produced a marked increase in the serum glucose, Total Cholesterol, LDL cholesterol, VLDL Cholesterol, Triglycerides and trim down the HDL level. We have weighed up the effect of Qurs Tabasheer on hepatic activity through estimating levels of various liver enzymes viz. Hexokinase, Glucose-6-Phosphatase and Fructose-1-6-biphosphatase in STZ diabetic wistar rats. Results In STZ-induced diabetic wistar rats level of Hexokinase, and Glucose-6-Phosphatase was decreased to a significant level while the level of fructose-1-6-biphophatase was augmented. Therapy with Qurs Tabasheer for 28 days to STZ-induced diabetic rats significantly reduces the level of serum glucose, total cholesterol, triglycerides, glucose-6-phosphatase and fructose-1-6-biphosphatase, while magnitude of HDL cholesterol and hexokinase was amplified. Conclusion Antihyperglycemic, antihyperlipidemic activity of Qurs Tabasheer extract in STZ- induced wistar rats was found to be more effective than standard oral hypoglycemic drug Glimepiride. PMID:23305114

  18. Antihyperglycemic, antihyperlipidemic and antioxidant effects of Dihar, a polyherbal ayurvedic formulation in streptozotocin induced diabetic rats.

    PubMed

    Patel, Snehal S; Shah, Rajendra S; Goyal, Ramesh K

    2009-07-01

    Present investigation was undertaken to evaluate antihyperglycemic, antihyperlipidemic and antioxidant activities of Dihar, a polyherbal formulation containing drugs from eight different herbs viz., Syzygium cumini, Momordica charantia, Emblica officinalis, Gymnema sylvestre, Enicostemma littorale, Azadirachta indica, Tinospora cordifolia and Curcuma longa in streptozotocin (STZ, 45 mg/kg iv single dose) induced type 1 diabetic rats. STZ produced a significant increase in serum glucose, cholesterol, triglyceride, very low density lipoprotein, low density lipoprotein, creatinine, and urea levels in diabetic rat. Treatment with Dihar (100 mg/kg) for 6 weeks produced decrease in STZ induced serum glucose and lipids levels and increased insulin levels as compared to control. Dihar produced significant decrease in serum creatinine and urea levels in diabetic rats. There was a significant decrease in reduced glutathione, superoxide dismutase, catalase levels and increase in thiobarbituiric acid reactive species levels in the liver of STZ-induced diabetic rats. Administration of Dihar to diabetic rats significantly reduced the levels of lipid paroxidation and increased the activities of antioxidant enzymes. The results suggest Dihar to be beneficial for the treatment of type 1 diabetes. PMID:19761040

  19. The Protective Effect of Fucoidan in Rats with Streptozotocin-Induced Diabetic Nephropathy

    PubMed Central

    Wang, Jing; Liu, Huaide; Li, Ning; Zhang, Quanbin; Zhang, Hong

    2014-01-01

    Diabetic nephropathy (DN) has long been recognized as the leading cause of end-stage renal disease, but the efficacy of available strategies for the prevention of DN remains poor. The aim of this study was to investigate the possible beneficial effects of fucoidan (FPS) in streptozotocin (STZ)-induced diabetes in rats. Wistar rats were made diabetic by injection of STZ after removal of the right kidney. FPS was administered to these diabetic rats for 10 weeks. Body weight, physical activity, renal function, and renal morphometry were measured after 10 weeks of treatment. In the FPS-treated group, the levels of blood glucose, BUN, Ccr and Ucr decreased significantly, and microalbumin, serum insulin and the ?2-MG content increased significantly. Moreover, the FPS-treated group showed improvements in renal morphometry. In summary, FPS can ameliorate the metabolic abnormalities of diabetic rats and delay the progression of diabetic renal complications. PMID:24886867

  20. Protective Effects of Fufang Xueshuantong on Diabetic Retinopathy in Rats

    PubMed Central

    Duan, Huihui; Huang, Jianmei; Li, Wei; Tang, Minke

    2013-01-01

    The aim of this study was to evaluate the protective effects of Fufang Xueshuantong (FXT) on diabetic retinopathy in rats induced by streptozotocin (STZ). Diabetes was induced in Sprague-Dawley rats by a single injection of 60 mg/kg STZ. One week after STZ, FXT 0.525 g/kg or 1.05 g/kg was administrated to the rats by intragastric gavage (ig) once daily consecutively for 24 weeks. The control rats and untreated STZ rats received vehicle the same way. At the end of the experiment, the erythrocyte aggregation and blood viscosity were assayed. The retina vessel morphology was observed in retinal digestive preparations. Expression of occludin and intercellular adhesion molecule-1 (ICAM-1) in retina was measured by western blotting. Expression of vascular endothelial growth factor (VEGF) and pigment epithelium derived factor (PEDF) in retina was detected by immunohistochemistry. The activity of aldose reductase in retina was investigated with a NADPH oxidation method. The results showed that, in STZ rats, there were distinct lesions in retinal vessel, including decrease of pericytes and increase of acellular capillaries, together with dilatation of retinal veins. The expression of VEGF and ICAM-1 increased, while the expression of PEDF and occludin decreased. The activity of aldose reductase elevated, and the whole blood viscosity, plasma viscosity, and erythrocyte aggregation also increased after STZ stimulation. FXT 0.525 g/kg and 1.05 g/kg demonstrated significant protective effects against STZ induced microvessel lesion in the retina with increased pericytes and reduced acellular capillaries. FXT also reduced the expression of VEGF and ICAM-1 and enhanced the expression of PEDF and occludin in STZ insulted rats. The activity of aldose reductase, the whole blood viscosity, plasma viscosity, and erythrocyte aggregation also decreased after FXT treatment. The results demonstrated that FXT has protective effect on STZ induced diabetic retinopathy in rats. PMID:24204392

  1. Antioxidant effect of carnosine treatment on renal oxidative stress in streptozotocin-induced diabetic rats.

    PubMed

    Yay, A; Akku?, D; Yap?slar, H; Balc?oglu, E; Sonmez, M F; Ozdamar, S

    2014-11-01

    Nitric oxide (NO) plays a significant role in the development of diabetic nephropathy. We investigated the effects of an antioxidant, carnosine, on streptozotocin (STZ)-induced renal injury in diabetic rats. We used four groups of eight rats: group 1, control; group 2, carnosine treated; group 3, untreated diabetic; group 4, carnosine treated diabetic. Kidneys were removed and processed, and sections were stained with periodic acid-Schiff (PAS) and subjected to eNOS immunohistochemistry. Examination by light microscopy revealed degenerated glomeruli, thickened basement membrane and glycogen accumulation in the tubules of diabetic kidneys. Carnosine treatment prevented the renal morphological damage caused by diabetes. Moreover, administration of carnosine decreased somewhat the oxidative damage of diabetic nephropathy. Appropriate doses of carnosine might be a useful therapeutic option to reduce oxidative stress and associated renal injury in diabetes mellitus. PMID:24834928

  2. Polyphenols-rich Cyamopsis tetragonoloba (L.) Taub. beans show hypoglycemic and β-cells protective effects in type 2 diabetic rats.

    PubMed

    Gandhi, Gopalsamy Rajiv; Vanlalhruaia, Pautu; Stalin, Antony; Irudayaraj, Santiagu Stephen; Ignacimuthu, Savarimuthu; Paulraj, Michael Gabriel

    2014-04-01

    The aim of this study was to evaluate the antidiabetic activity of Cyamopsis tetragonoloba (L.) Taub. (Fabaceae) beans in high-fat diet (HFD) fed-streptozotocin (STZ)-induced type 2 diabetic rats. Dose dependent response of oral treatment of C. tetragonoloba beans' methanol extract (CTme) (200 and 400mg/kg b wt.) was assessed by measuring fasting blood glucose, changes in body weight, plasma insulin, homeostasis model assessment of insulin resistance (HOMA-IR), total cholesterol, triglycerides, oral glucose tolerance, intraperitoneal insulin tolerance, hepatic glycogen, marker enzymes of carbohydrate metabolism in HFD fed-STZ-induced type 2 diabetic rats. Histology and immunohistochemical analysis of pancreatic islets were also performed. High-performance liquid chromatography (HPLC) analysis of CTme showed the presence of polyphenols such as gallic acid and caffeic acid in the concentrations of 2.46% (W/W) and 0.32% (W/W). CTme significantly reverted the altered biochemical parameters to near normal levels in diabetic rats. Furthermore CTme showed the protective effect on the β-cells of pancreatic tissues in diabetic rats. These findings indicate that C. tetragonoloba beans have therapeutic potential in HFD fed-STZ-induced hyperglycemia; therefore this can be used in the management of type 2 diabetes. PMID:24525096

  3. Renal oxidative stress and nitric oxide production in streptozotocin-induced diabetic nephropathy in rats: the possible modulatory effects of garlic (Allium sativum L.).

    PubMed

    Mariee, Amr D; Abd-Allah, Gamil M; El-Yamany, Mohamad F

    2009-03-01

    The purpose of the present study was to investigate the effects of garlic (Allium sativum L.) on the diabetic nephropathy and oxidative stress induced by STZ (streptozotocin) in rats. Diabetes was induced in Male Sprague-Dawley rats by administering a single intraperitoneal injection of STZ (60 mg/kg of body weight). Administration of garlic, prepared as FGH (fresh garlic homogenate) significantly attenuated STZ-induced diabetic nephropathy as evaluated by assessment of serum glucose, insulin, total TAG (triacylglycerol), TC (total cholesterol) and Ccr (creatinine clearance) in control and STZ-induced diabetic rats. Urinary excretions of albumin and NAG (N-acetyl-beta-D-glucosaminidase) were also reduced following the treatment with FGH. In addition, significant inhibition of TBARSs (thiobarbituric acid-reacting substances) with a marked improvement of GSH content in the kidney homogenates was also observed. Moreover, renal tissue content and urinary excretion of nitrites were markedly decreased in this model, and virtually enhanced to the same levels as in the non-diabetic kidney following FGH supplementation. These data revealed that FGH has the ability to ameliorate STZ-induced diabetic nephropathy possibly through participation in the inhibition of oxidative damage to kidney and/or increased kidney nitric oxide bioavailability. PMID:18588510

  4. AB139. Studies on the mechanism of testicular dysfunction in the early stage of a streptozotocin induced diabetic rat model

    PubMed Central

    Xu, Yongde; Lei, Hongen; Guan, Ruili; Gao, Zhezhu; Li, Huixi; Wang, Lin; Song, Weidong; Gao, Bing; Xing, Zhongcheng

    2014-01-01

    Streptozotocin (STZ) induced diabetic model has been widely used to study the effects of diabetes mellitus (DM) on male infertility, but it remains unclear whether the responses in this model are due to hyperglycemia or STZ per se. This study was designed to investigate the mechanism of STZ on testicular dysfunction. In the present study, sperm characteristics, serum testosterone, steroidogenic enzymes (StAR and 3?-HSD), and the vimentin apical extension of sertoli cells decreased significantly in the STZ group compared with those in the normal controls (P<0.05), while Johnsens score, testicular lipid peroxidation, spermatogenic cell apoptosis, and the expressions of NF-?B and Wnt4 significantly increased (P<0.05). Insulin replacement mainly restored the decreased serum testosterone and steroidogenic enzymes, but not other parameters. The results indicated that spermatogenic dysfunction in the early stage of STZ-induced diabetic rats was due to direct STZ cytotoxity to sertoli cells, which could be regulated by Wnt4 and NF-?B, while steroidogenic dysfunction might be a direct or indirect consequence of insulin deficiency. The results suggested that STZ-induced diabetic model, at least in the early stage, is not suitable to study the diabetes-related spermatogenic dysfunction.

  5. Pharmacological Evaluation of Sugar Remedy, A Polyherbal Formulation, on Streptozotocin-Induced Diabetic Mellitus in Rats

    PubMed Central

    Singhal, Sandeep; Rathore, Arvind Singh; Lohar, Vikram; Dave, Rakesh; Dave, Jeetesh

    2014-01-01

    In the present study, Sugar Remedy, a polyherbal formulation (manufactured by Umalaxmi Organics Pvt Ltd, Jodhpur, Rajasthan, India) was evaluated for its antihyperglycemic, antihyperlipidemic, and antioxidant effects against normal and streptozotocin (STZ)-induced diabetic rats. Type II diabetes was induced in male Wistar rats by administration of a single intraperitoneal (IP) injection of STZ at a dose of 60 mg/kg. Effects of three different doses of Sugar Remedy suspension (185, 370, and 740 mg/kg/day, orally) and Metformin (500 mg/kg/day, orally) administered for 21 days were studied on parameters such as blood glucose, lipid profile, and antioxidant levels. Results were analyzed using one-way analysis of variance (ANOVA) followed by Dunnett's test. No significant changes were noticed in blood glucose, serum lipid levels, and kidney parameters in normal rats treated with Sugar Remedy suspension alone. The efficacy of Sugar Remedy as an antihyperglycemic, antihyperlipidemic, and antioxidant agent in STZ-induced diabetes was comparable to that of the standard, 500 mg/kg of Metformin. Present findings provide experimental evidence that Sugar Remedy has significant antihyperglycemic, antihyperlipidemic, and antioxidative effects in diabetic experimental rats. Hence, Sugar Remedy may be regarded as a promising natural and safe remedy for the prevention or delay of diabetic complications. PMID:25161924

  6. Dendrobium officinale Prevents Early Complications in Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Hou, Shao-zhen; Liang, Chu-yan; Liu, Hua-zhen; Zhu, Dong-mei; Wu, Ya-yun; Liang, Jian; Zhao, Ya; Guo, Jian-ru; Huang, Song; Lai, Xiao-Ping

    2016-01-01

    Background. Dendrobium officinale (DO) Kimura et Migo is a precious Chinese herb that is considered beneficial for health due to its antioxidant and antidiabetes properties, and so on. In this research, we try to determine the preventive effect of DO on the early complications of STZ-induced diabetic rats. Methods. Type 1 diabetic rats were produced with a single intraperitoneal injection of STZ (50 mg/kg). DO (1 g/kg/day) was then orally administered for 5 weeks. Blood glucose, TC, TG, BUN, CREA, and GSH-PX levels were determined, and electroretinographic activity and hypoalgesia were investigated. Pathological sections of the eyes, hearts, aortas, kidneys, and livers were analyzed. Results. Treatment with DO significantly attenuated the serum levels of TC, TG, BUN, and CREA, markedly increased the amplitudes of ERG a- and b-waves and Ops, and reduced the hypoalgesia and histopathological changes of vital organs induced by hyperglycemia. The protective effect of DO in diabetic rats may be associated with its antioxidant activity, as evidenced by the marked increase in the serum level of glutathione peroxidase. However, DO had no significant effect on blood glucose levels and bodyweight of diabetic rats. Conclusions. DO supplementation is an effective treatment to prevent STZ-induced diabetic complications.

  7. Effects of Aqueous Extract of Berberis integerrima Root on Some Physiological Parameters in Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Ashraf, Hossein; Heidari, Reza; Nejati, Vahid; Ilkhanipoor, Minoo

    2013-01-01

    Diabetes mellitus is a common endocrine disorder. Anti-diabetic agents from natural and synthetic sources are available for the treatment of this disease. Berberis integerrima is a medicinal shrub used in conventional therapy for a number of diseases. The aim of the present study was to investigate the effects of aqueous extract of Berberis integerrima root (AEBI) on some physiological parameters in normal and streptozotocin-induced (STZ-induced) diabetic male Wistar rats. STZ-induced diabetic rats showed significant increases in the levels of blood glucose, triglycerides (TG), total cholesterol (TC), low density lipoprotein LDL-cholesterol (LDL-C), creatinine (Cr), urea, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bilirubin while body weight, high density lipoprotein HDL-cholesterol (HDL-C) and total protein levels were significantly decreased compared to normal rats. Treatment of diabetic rats with different doses of aqueous extract of Berberis integerrima root (250 and 500 mg/Kg bw) resulted in a significant decrease in blood glucose, triglycerides, cholesterol, LDL-cholesterol, ALT, AST, ALP, total bilirubin, creatinine and urea while HDL-cholesterol and total protein levels were markedly increased after six weeks compared to untreated diabetic rats. The effects of the AEBI at dose of 500 mg/Kg in all parameters except blood glucose (similar) is more than to the standard drug, glibenclamide (0.6 mg/Kg, p.o.). The results of this study indicate that the tested aqueous extract of Berberis integerrima root possesses hypoglycemic, hypolipidemic and antioxidant effects in STZ-induced diabetic rats. PMID:24250618

  8. Antihyperglycemic and antihyperlipidemic activities of aqueous extract of Hericium erinaceus in experimental diabetic rats

    PubMed Central

    2013-01-01

    Background Hericium erinaceus, as a commonly used medicine or food, has attracted much attention due to its health effects when used as a home remedy for some diseases. The aim of this work was to investigate the hypoglycemic and hypolipidemic effects of aqueous extract of Hericium erinaceus (AEHE) in streptozotocin (STZ)-induced diabetic rats. Methods Diabetes was induced in Wistar rats by the administration of STZ (55 mg/kg BW.) intraperitoneally. AEHE (100 and 200 mg/kg BW.) was administered for a period of 28 days. The effects of AEHE on glucose, insulin, and lipid files in blood, and oxidative stress parameters in the liver were evaluated. The body weights of rats were recorded at day 0, 14 and 28th days. Results The administration of AEHE for 28 days in STZ diabetic rats resulted in a significant decrease in serum glucose level and a significant rise in serum insulin level. AEHE treatment attenuated lipid disorders. In addition, AEHE administration increased the activities of CAT, SOD, and GSH-Px, and GSH level, and reduced MDA level in the liver tissue significantly. Conclusion Our results suggest that AEHE possesses hypoglycemic, hypolipidemic, and antioxidant properties in STZ-induced diabetes rats. PMID:24090482

  9. Effects of N-adamantyl-4-methylthiazol-2-amine on hyperglycemia, hyperlipidemia and oxidative stress in streptozotocin-induced diabetic rats.

    PubMed

    Yang, Seung-Ju; Je Lee, Woo; Kim, Eun-A; Dal Nam, Kee; Hahn, Hoh-Gyu; Young Choi, Soo; Cho, Sung-Woo

    2014-08-01

    Thiazole derivatives are attractive candidates for drug development because they can be efficiently synthesized and are active against a number of diseases and conditions, including diabetes. In our present study, we investigated the anti-inflammatory and antioxidant properties of N-adamantyl-4-methylthiazol-2-amine (KHG26693), a new thiazole derivative, in a streptozotocin (STZ)-induced model of diabetes mellitus. STZ-induced diabetic rats were intraperitoneally administered KHG26693 (3mg/kg-body weight/day) for 4 weeks. KHG26693 administration significantly decreased blood glucose, triglycerides, and cholesterol and increased insulin. KHG26693 also suppressed several inflammatory responses in STZ-induced diabetic rats, as evidenced by decreased levels of serum tumor necrosis factor-?, interleukin-1?, and nitric oxide. Additionally, KHG26693 significantly modulated hepatic lipid peroxidation, catalase and superoxide dismutase activity, and the nonenzymatic antioxidant status (e.g., vitamins C and E), and reduced the glutathione content. These anti-inflammatory/antioxidative actions occurred as a result of the downregulation of inducible nitric oxide synthase and nuclear factor-kappa B. Taken together, our results suggest that KHG26693 successfully reduces the production of oxidative stress in STZ-induced diabetic rats by regulating the oxidation-reduction system, specifically increasing antioxidant capacity. Furthermore, KHG26693 treatment significantly reverted the key enzymes of glucose metabolism, such as glucokinase, glucose-6-phosphatase, glycogen synthase, glycogen phosphorylase, and fructose-1,6-bisphosphatase, to near-normal levels in liver tissues. These results indicate that KHG26693 normalizes disturbed glucose metabolism by enhancing glucose utilization and decreasing liver glucose production via insulin release, suggesting the possibility of future diabetes treatments. PMID:24797782

  10. Enriched Environment Protects the Optic Nerve from Early Diabetes-Induced Damage in Adult Rats

    PubMed Central

    Dorfman, Damin; Aranda, Marcos L.; Rosenstein, Ruth E.

    2015-01-01

    Diabetic retinopathy is a leading cause of reduced visual acuity and acquired blindness. Axoglial alterations of the distal (close to the chiasm) optic nerve (ON) could be the first structural change of the visual pathway in streptozotocin (STZ)-induced diabetes in rats. We analyzed the effect of environmental enrichment on axoglial alterations of the ON provoked by experimental diabetes. For this purpose, three days after vehicle or STZ injection, animals were housed in enriched environment (EE) or remained in a standard environment (SE) for 6 weeks. Anterograde transport, retinal morphology, optic nerve axons (toluidine blue staining and phosphorylated neurofilament heavy immunoreactivity), microglia/macrophages (ionized calcium binding adaptor molecule 1 (Iba-1) immunoreactivity), astrocyte reactivity (glial fibrillary acid protein-immunostaining), myelin (myelin basic protein immunoreactivity), ultrastructure, and brain derived neurotrophic factor (BDNF) levels were assessed in non-diabetic and diabetic animals housed in SE or EE. No differences in retinal morphology or retinal ganglion cell number were observed among groups. EE housing which did not affect the STZ-induced weight loss and hyperglycemia, prevented a decrease in the anterograde transport from the retina to the superior colliculus, ON axon number, and phosphorylated neurofilament heavy immunoreactivity. Moreover, EE housing prevented an increase in Iba-1 immunoreactivity, and astrocyte reactivity, as well as ultrastructural myelin alterations in the ON distal portion at early stages of diabetes. In addition, EE housing avoided a decrease in BDNF levels induced by experimental diabetes. These results suggest that EE induced neuroprotection in the diabetic visual pathway. PMID:26312758

  11. Enriched Environment Protects the Optic Nerve from Early Diabetes-Induced Damage in Adult Rats.

    PubMed

    Dorfman, Damin; Aranda, Marcos L; Rosenstein, Ruth E

    2015-01-01

    Diabetic retinopathy is a leading cause of reduced visual acuity and acquired blindness. Axoglial alterations of the distal (close to the chiasm) optic nerve (ON) could be the first structural change of the visual pathway in streptozotocin (STZ)-induced diabetes in rats. We analyzed the effect of environmental enrichment on axoglial alterations of the ON provoked by experimental diabetes. For this purpose, three days after vehicle or STZ injection, animals were housed in enriched environment (EE) or remained in a standard environment (SE) for 6 weeks. Anterograde transport, retinal morphology, optic nerve axons (toluidine blue staining and phosphorylated neurofilament heavy immunoreactivity), microglia/macrophages (ionized calcium binding adaptor molecule 1 (Iba-1) immunoreactivity), astrocyte reactivity (glial fibrillary acid protein-immunostaining), myelin (myelin basic protein immunoreactivity), ultrastructure, and brain derived neurotrophic factor (BDNF) levels were assessed in non-diabetic and diabetic animals housed in SE or EE. No differences in retinal morphology or retinal ganglion cell number were observed among groups. EE housing which did not affect the STZ-induced weight loss and hyperglycemia, prevented a decrease in the anterograde transport from the retina to the superior colliculus, ON axon number, and phosphorylated neurofilament heavy immunoreactivity. Moreover, EE housing prevented an increase in Iba-1 immunoreactivity, and astrocyte reactivity, as well as ultrastructural myelin alterations in the ON distal portion at early stages of diabetes. In addition, EE housing avoided a decrease in BDNF levels induced by experimental diabetes. These results suggest that EE induced neuroprotection in the diabetic visual pathway. PMID:26312758

  12. Hemodynamic alterations in chronically conscious unrestrained diabetic rats

    SciTech Connect

    Carbonell, L.F.; Salmon, M.G.; Garcia-Estan, J.; Salazar, F.J.; Ubeda, M.; Quesada, T.

    1987-05-01

    Important cardiovascular dysfunctions have been described in streptozotocin (STZ)-diabetic rats. To determine the influence of these changes on the hemodynamic state and whether insulin treatment can avoid them, different hemodynamic parameters, obtained by the thermodilution method, were studied in STZ-induced (65 mg/kg) diabetic male Wistar rats, as well as in age-control, weight-control, and insulin-treated diabetic ones. Plasma volume was measured by dilution of radioiodinated (/sup 125/I) human serum albumin. All rats were examined in the conscious, unrestrained state 12 wk after induction of diabetes or acidified saline (pH 4.5) injection. At 12 wk of diabetic state most important findings were normotension, high blood volume, bradycardia, increase in stroke volume, cardiac output, and cardiosomatic ratio, and decrease in total peripheral resistance and cardiac contractility and relaxation (dP/dt/sub max/ and dP/dt/sub min/ of left ventricular pressure curves). The insulin-treated diabetic rats did not show any hemodynamic differences when compared with the control animals. These results suggest that important hemodynamic alterations are present in the chronic diabetic states, possibly conditioning congestive heart failure. These alterations can be prevented by insulin treatment.

  13. Metabonomic study on the plasma of streptozotocin-induced diabetic rats treated with Ge Gen Qin Lian Decoction by ultra high performance liquid chromatography-mass spectrometry.

    PubMed

    Zhang, Qiyun; Xu, Guoliang; Li, Jia; Guo, Xiaofeng; Wang, Hong; Li, Bingtao; Tu, Jun; Zhang, Huashan

    2016-02-20

    Changes in endogenous metabolites in the plasma of streptozotocin (STZ)-induced diabetic rats treated with Ge Gen Qin Lian Decoction (GGQLD) were studied. The endogenous compounds in plasma were detected using ultra high performance liquid chromatography coupled with quadrupole-time-of-flight tandem mass spectrometry (UHPLC-Q-TOF-MS). Rats were divided into three groups: control, model, and administration (4.95g crude drug/kg body weight). After the final administration, plasma samples from the three groups were analyzed using metabonomics. The three sample groups could be clearly distinguished. The administration group exhibited a distinct return to the levels of phytosphingosine and dihydrosphingosine of the control group according to the principal component analysis score, and the corresponding biomarkers were defined. Significant changes in endogenous metabolites, such as dihydrosphingosine, phytosphingosine, cholylglycine, and pantothenic acid, were identified in STZ-induced diabetic rats. These biochemical changes are associated with the metabolism of sphingolipids, fats, and acetyl coenzyme-A, which could be useful to further investigate the characteristics of STZ-induced diabetes mellitus and the therapeutic mechanism of action of GGQLD. This metabonomic analysis could provide a useful starting point toelucidate the therapeutic effects and mechanism of action of GGQLD in diabetes mellitus. PMID:26744987

  14. Bacterial Flora Changes in Conjunctiva of Rats with Streptozotocin-Induced Type I Diabetes

    PubMed Central

    Qin, Yali; Luo, Dan; Yang, Shufei; Kou, Xinyun; Zi, Yingxin; Deng, Tingting; Jin, Ming

    2015-01-01

    Background The microbiota of both humans and animals plays an important role in their health and the development of disease. Therefore, the bacterial flora of the conjunctiva may also be associated with some diseases. However, there are no reports on the alteration of bacterial flora in conjunctiva of diabetic rats in the literature. Therefore, we investigated the changes in bacterial flora in bulbar conjunctiva of rats with streptozotocin (STZ)-induced type I diabetes. Methods A high dose of STZ (60 mg/kg, i.p.) was injected into Sprague-Dawley (SD) rats to induce type I diabetes mellitus (T1DM). The diabetic rats were raised in the animal laboratory and at 8 months post-injection of STZ swab samples were taken from the bulbar conjunctiva for cultivation of aerobic bacteria. The bacterial isolates were identified by Gram staining and biochemical features. The identified bacteria from both diabetic and healthy rats were then compared. Results The diabetic and healthy rats had different bacterial flora present in their bulbar conjunctiva. In total, 10 and 8 bacterial species were found in the STZ and control groups, respectively, with only three species (Enterococcus faecium, Enterococcus gallinarum and Escherichia coli) shared between the two groups. Gram-positive bacteria were common in both groups and the most abundant was Enterococcus faecium. However, after the development of T1DM, the bacterial flora in the rat bulbar conjunctiva changed considerably, with a reduced complexity evident. Conclusions STZ-induced diabetes caused alterations of bacterial flora in the bulbar conjunctiva in rats, with some bacterial species disappearing and others emerging. Our results indicate that the conjunctival bacterial flora in diabetic humans should be surveyed for potential diagnostic markers or countermeasures to prevent eye infections in T1DM patients. PMID:26176548

  15. Hypoglycemic and ?-cells regenerative effects of Aegle marmelos (L.) Corr. bark extract in streptozotocin-induced diabetic rats.

    PubMed

    Gandhi, Gopalsamy Rajiv; Ignacimuthu, Savarimuthu; Paulraj, Michael Gabriel

    2012-05-01

    The aim of this study was to examine the antidiabetic potential of Aegle marmelos (L.) Corr. (Rutaceae) bark in a diabetic rat model. Dose dependent effects of methanol extract of Aegle marmelos bark (AM) (200 and 400 mg/kg) on blood glucose, plasma insulin, glycated haemoglobin (HbA1c), total protein, hepatic glycogen, marker enzymes of hepatic function and carbohydrate metabolism were evaluated in (streptozotocin) STZ-induced diabetic rats by oral administration for 30 days. Structural integrity of pancreatic islets was assessed by routine histology while, their functional status was assessed by immunolocalization for insulin. High-performance liquid chromatography (HPLC) study established that AM contained antihyperglycemic constituents, aegelin (1.27% w/w) and lupeol (0.29% w/w). AM at 200 and 400 mg/kg showed significant reduction in blood glucose level by 19.14% and 47.32%, respectively in diabetic rats. AM treatment significantly increased insulin level, and produced similar effects on other biochemical parameters. Histological studies showed the regenerative effect of AM on the ?-cells of diabetic rats. Immunohistochemical observations in the extract treated diabetic rats showed increased insulin-immunoreactive ?-cells. These findings suggest that A. marmelos bark extract has the therapeutic potential in STZ-induced hyperglycemia; hence it can be used in the treatment of diabetes mellitus. PMID:22310238

  16. Assessment of the Protective Role of Prenatal Zinc versus Insulin Supplementation on Fetal Cardiac Damage Induced by Maternal Diabetes in Rat Using Caspase-3 and KI67 Immunohistochemical Stains

    PubMed Central

    Shams, Ahmed S.; Mohammed, Mona H.; Loka, Mona M.; Abdel Rahman, Gamal M.

    2016-01-01

    Maternal diabetes mellitus (DM) affects early organogenesis. Metabolic disorders of DM are associated with a depleted zinc status. This study evaluated the effect of maternal DM on cardiac development of rat fetuses and protective roles of prenatal zinc versus insulin supplementation. Pregnant rats were divided into 4 groups ((I) control, (II) STZ-induced DM, (III) STZ-induced DM treated with Zn, and (IV) STZ induced DM treated with insulin), all sacrificed on GD 20. Fetal heart weight of diabetic rats showed significant decrease compared to controls (P < 0.05). H&E stained section of controls had normal appearance of the myocardium, compared to diabetics that showed myocardial disarray with characteristic degenerative changes. Sections of zinc treated group showed restored architecture of normal myofibrils with minimal degenerative changes, while those of insulin treated group show partial restoration of the normal architecture of cardiomyocytes with focal improvement of cardiac tissue. Caspase-3 immunostained slides showed positive cytoplasmic immunoreactivity in diabetic group. But KI67 immunostained slides revealed negative nuclear immunoreaction in diabetics. We observed that gestational diabetes was associated with increased risk of fetal myocardial damage that might be caused by increased apoptotic level. Treating diabetic pregnant subjects with zinc and insulin was associated with improvement in myocardial integrity. PMID:26925289

  17. Protective effect of polyphenol-containing azuki bean (Vigna angularis) seed coats on the renal cortex in streptozotocin-induced diabetic rats.

    PubMed

    Sato, Shin; Yamate, Jyoji; Hori, Yuuka; Hatai, Asako; Nozawa, Megumi; Sagai, Masaru

    2005-09-01

    This study was undertaken to investigate the effect of azuki bean (Vigna angularis) seed coats (ABSC), which contain polyphenols, on the infiltration of macrophages and the progression of diabetic nephropathy in streptozotocin (STZ)-induced diabetic rats. The diabetic rats were divided into three groups with 0% (commercial diet), 0.1% and 1.0% ABSC diets. The vehicle-injected controls were given a commercial diet. At 10 weeks, the macrophage kinetics, the degree of fibrosis in glomeruli and mRNA expression for monocyte chemoattractant protein-1 (MCP-1) were examined. There was no difference in plasma glucose levels between diabetic rats treated with and without ABSC. The plasma levels of malondialdehyde (MDA) in the ABSC-treated diabetic rats were significantly lower than those in the untreated diabetic rats. Histopathologically, the percentage of the fibrotic areas stained by Sirius red stain in the glomeruli in the ABSC-treated diabetic rats was lower than in the untreated diabetic rats. ED1-positive macrophages in the glomeruli and tubulointerstitium in the untreated diabetic rats showed a significant increase in number compared with the controls. In contrast, the number of macrophages in the ABSC-treated diabetic rats was smaller than that in untreated diabetic rats. MCP-1 mRNA expression, estimated by real-time quantitative RT-PCR, was increased 2.5-fold in the untreated diabetic rat kidney, while a lower level was observed in the ABSC-treated diabetic rats. In conclusion, our results suggest that ABSC treatments suppress the increased number of infiltrating macrophages and MCP-1 mRNA expression, and attenuated the glomerular expansion in STZ-induced rat diabetic nephropathy. PMID:16115543

  18. Beneficial effects of aloe vera leaf gel extract on lipid profile status in rats with streptozotocin diabetes.

    PubMed

    Rajasekaran, Subbiah; Ravi, Kasiappan; Sivagnanam, Karuran; Subramanian, Sorimuthu

    2006-03-01

    The effect of diabetes mellitus on lipid metabolism is well established. The association of hyperglycaemia with an alteration of lipid parameters presents a major risk for cardiovascular complications in diabetes. Many secondary plant metabolites have been reported to possess lipid-lowering properties. The present study was designed to examine the potential anti-hyperlipidaemic efficacy of the ethanolic extract from Aloe vera leaf gel in streptozotocin (STZ)-induced diabetic rats. 2. Oral administration of Aloe vera gel extract at a dose of 300 mg/kg bodyweight per day to STZ-induced diabetic rats for a period of 21 days resulted in a significant reduction in fasting blood glucose, hepatic transaminases (aspartate aminotransferase and alanine aminotransferase), plasma and tissue (liver and kidney) cholesterol, triglycerides, free fatty acids and phospholipids and a significant improvement in plasma insulin. 3. In addition, the decreased plasma levels of high-density lipoprotein-cholesterol and increased plasma levels of low-density lipoprotein-and very low-density lipoprotein-cholesterol in diabetic rats were restored to near normal levels following treatment with the extract. 4. The fatty acid composition of the liver and kidney was analysed by gas chromatography. The altered fatty acid composition in the liver and kidney of diabetic rats was restored following treatment with the extract. 5. Thus, the results of the present study provide a scientific rationale for the use of Aloe vera as an antidiabetic agent. PMID:16487267

  19. Effect of Commiphora mukul gum resin on hepatic marker enzymes, lipid peroxidation and antioxidants status in pancreas and heart of streptozotocin induced diabetic rats

    PubMed Central

    Ramesh, B; Karuna, R; Sreenivasa, Reddy S; Haritha, K; Sai, Mangala D; Sasi, Bhusana Rao B; Saralakumari, D

    2012-01-01

    Objective To study the antioxidant efficacy of Commiphora mukul (C. mukul) gum resin ethanolic extract in streptozotocin (STZ) induced diabetic rats. Methods The male Wistar albino rats were randomly divided into four groups of eight animals each: Control group (C), CM-treated control group (C+CMEE), Diabetic control group (D), CM- treated diabetic group (D+CMEE). Diabetes was induced by intraperitoneal injection of STZ (55 mg/kg/ bwt). After being confirmed the diabetic rats were treated with C. mukul gum resin ethanolic extract (CMEE) for 60 days. The biochemical estimations like antioxidant, oxidative stress marker enzymes and hepatic marker enzymes of tissues were performed. Results The diabetic rats showed increased level of enzymatic activities aspartate aminotransaminase (AST), alanine aminotransaminase (ALT) in liver and kidney and oxidative markers like lipid peroxidation (LPO) and protein oxidation (PO) in pancreas and heart. Antioxidant enzyme activities were significantly decreased in the pancreas and heart compared to control group. Administration of CMEE (200 mg/kg bw) to diabetic rats for 60 days significantly reversed the above parameters towards normalcy. Conclusions In conclusion, our data indicate the preventive role of C. mukul against STZ-induced diabetic oxidative stress; hence this plant could be used as an adjuvant therapy for the prevention and/or management of diabetes and aggravated antioxidant status. PMID:23569867

  20. Centella asiatica Attenuates Diabetes Induced Hippocampal Changes in Experimental Diabetic Rats

    PubMed Central

    Srinivasarao, Nelli; Swapna Rekha, Somesula; Muniandy, Sekaran

    2014-01-01

    Diabetes mellitus has been reported to affect functions of the hippocampus. We hypothesized that Centella asiatica, a herb traditionally being used to improve memory, prevents diabetes-related hippocampal dysfunction. Therefore, the aim of this study was to investigate the protective role of C. asiatica on the hippocampus in diabetes. Methods. Streptozotocin- (STZ-) induced adult male diabetic rats received 100 and 200?mg/kg/day body weight (b.w) C. asiatica leaf aqueous extract for four consecutive weeks. Following sacrifice, hippocampus was removed and hippocampal tissue homogenates were analyzed for Na+/K+-, Ca2+- and Mg2+-ATPases activity levels. Levels of the markers of inflammation (tumor necrosis factor, TNF-?; interleukin, IL-6; and interleukin, IL-1?) and oxidative stress (lipid peroxidation product: LPO, superoxide dismutase: SOD, catalase: CAT, and glutathione peroxidase: GPx) were determined. The hippocampal sections were visualized for histopathological changes. Results. Administration of C. asiatica leaf aqueous extract to diabetic rats maintained near normal ATPases activity levels and prevents the increase in the levels of inflammatory and oxidative stress markers in the hippocampus. Lesser signs of histopathological changes were observed in the hippocampus of C. asiatica leaf aqueous extract treated diabetic rats. Conclusions. C. asiatica leaf protects the hippocampus against diabetes-induced dysfunction which could help to preserve memory in this condition. PMID:25161691

  1. Centella asiatica Attenuates Diabetes Induced Hippocampal Changes in Experimental Diabetic Rats.

    PubMed

    Giribabu, Nelli; Srinivasarao, Nelli; Swapna Rekha, Somesula; Muniandy, Sekaran; Salleh, Naguib

    2014-01-01

    Diabetes mellitus has been reported to affect functions of the hippocampus. We hypothesized that Centella asiatica, a herb traditionally being used to improve memory, prevents diabetes-related hippocampal dysfunction. Therefore, the aim of this study was to investigate the protective role of C. asiatica on the hippocampus in diabetes. Methods. Streptozotocin- (STZ-) induced adult male diabetic rats received 100 and 200?mg/kg/day body weight (b.w) C. asiatica leaf aqueous extract for four consecutive weeks. Following sacrifice, hippocampus was removed and hippocampal tissue homogenates were analyzed for Na(+)/K(+)-, Ca(2+)- and Mg(2+)-ATPases activity levels. Levels of the markers of inflammation (tumor necrosis factor, TNF-?; interleukin, IL-6; and interleukin, IL-1?) and oxidative stress (lipid peroxidation product: LPO, superoxide dismutase: SOD, catalase: CAT, and glutathione peroxidase: GPx) were determined. The hippocampal sections were visualized for histopathological changes. Results. Administration of C. asiatica leaf aqueous extract to diabetic rats maintained near normal ATPases activity levels and prevents the increase in the levels of inflammatory and oxidative stress markers in the hippocampus. Lesser signs of histopathological changes were observed in the hippocampus of C. asiatica leaf aqueous extract treated diabetic rats. Conclusions. C. asiatica leaf protects the hippocampus against diabetes-induced dysfunction which could help to preserve memory in this condition. PMID:25161691

  2. Decreased cholinergic receptor expression in the striatum: motor function deficit in hypoglycemic and diabetic rats.

    PubMed

    Sherin, A; Peeyush, K T; Jayanarayanan, S; Amee, K K; Paulose, C S

    2012-01-01

    Hypoglycemic brain injury is a common and serious complication of insulin therapy associated with diabetes. This study evaluated the effect of insulin-induced hypoglycemia and STZ-induced diabetes on striatal cholinergic receptors and enzyme expression and on motor function. Cholinergic enzymes: AChE and ChAT gene expression, radioreceptor binding assay and immunohistochemistry of muscarinic M1, M3 receptors and ?7nAChR were carried out. Motor performance on grid walk test was analysed. AChE and ChAT expression significantly downregulated in hypoglycemic and diabetic rats. Total muscarinic and Muscarinic M3 receptor binding decreased in hypoglycemic rats compared to diabetic rats whereas muscarinic M1 receptor binding increased in hypoglycemic rats compared to diabetic rats. Real-time PCR analysis and confocal imaging of muscarinic M1, M3 receptors confirmed the changes in muscarinic receptor binding in hypoglycemic and diabetic rats. In hypoglycemic rats, ?7nAChR expression significantly up regulated compared to diabetic rats. Grid walk test demonstrated the impairment in motor function and coordination in hypoglycemic and hyperglycemic rats. Neurochemical changes along with the behavioral data implicate a role for impaired striatal cholinergic receptor function inducing motor function deficit induced by hypo and hyperglycemia. Hypoglycemia exacerbated the neurobehavioral deficit in diabetes which has clinical significance in the treatment of diabetes. PMID:21796364

  3. Effect of Aloe vera (L.) Burm. fil. leaf gel and pulp extracts on kidney in type-II diabetic rat models.

    PubMed

    Bolkent, Sehnaz; Akev, Nuriye; Ozsoy, Nurten; Sengezer-Inceli, Meliha; Can, Ayse; Alper, Okyar; Yanardag, Refiye

    2004-01-01

    Significant degenerative changes were observed in the kidney tissue of untreated neonatal streptozotocin (n0STZ)-induced type-II diabetic rats. These degenerative changes were diminished in the kidney tissue of diabetic animals given glibenclamide and Aloe leaf gel and pulp extracts. Kidney lipid peroxidation levels were increased in diabetic rats compared to healthy rats; these levels were higher in rats treated with glibenclamide than in those which received Aloe extracts. Serum urea and creatinine levels were higher in diabetic rats in comparison to healthy rats. The administration of Aloe gel extract and glibenclamide decreased serum urea and creatinine levels in comparison to diabetic controls. Only A. vera leaf gel extract showed improvement both in histological and biochemical parameters suggesting a protective effect of A. vera on mild damage caused by type-II diabetes on kidney tissue. PMID:15274480

  4. Fermented soy permeate reduces cytokine level and oxidative stress in streptozotocin-induced diabetic rats.

    PubMed

    Malardé, Ludivine; Groussard, Carole; Lefeuvre-Orfila, Luz; Vincent, Sophie; Efstathiou, Théo; Gratas-Delamarche, Arlette

    2015-01-01

    Oxidative stress and inflammation are involved in the development of type 1 diabetes and its complications. Because two compounds found in soy, that is, isoflavones and alpha-galactooligosaccharides, have been shown to exert antioxidant and anti-inflammatory effects, this study aimed to assess the effects of a dietary supplement containing these two active compounds, the fermented soy permeate (FSP). We hypothesized that FSP would be able to reduce in vivo oxidative stress and inflammation in streptozotocin (STZ)-induced type 1 diabetic rats. Thirty male Wistar rats were divided into the control placebo, diabetic placebo, and diabetic FSP-supplemented groups. They received daily, by oral gavage, water (placebo groups) or diluted FSP (0.1 g/day; FSP-supplemented group). After 3 weeks, glycemic regulation (glycemia and fructosamine level); the plasma level of carboxymethyllysine (CML), a marker of systemic oxidative stress in diabetes; and the plasma levels of inflammatory markers (CRP, IL-1β, IL-6, and uric acid) were evaluated. Markers of oxidative damage (isoprostanes and GSH/GSSG), antioxidant enzymatic activity (SOD and GPX), and Mn-SOD content were determined in skeletal muscle (gastrocnemius). Diabetic placebo rats exhibited higher CML levels, lower SOD and GPX activities, and decreased Mn-SOD contents. FSP supplementation in diabetic animals normalized the CML and antioxidant enzymatic activity levels and tended to increase Mn-SOD expression. The markers of inflammation whose levels were increased in the diabetic placebo group were markedly decreased by FSP (IL-1β: -75%, IL-6: -46%, and uric acid: -17%), except for CRP. Our results demonstrate that FSP exhibited antioxidant and anti-inflammatory properties in vivo in STZ-induced diabetic rats. PMID:25314273

  5. Effects of Gymnema sylvestre extract on the pharmacokinetics and pharmacodynamics of glimepiride in streptozotocin induced diabetic rats.

    PubMed

    Kamble, Bhagyashree; Gupta, Ankur; Moothedath, Ismail; Khatal, Laxman; Janrao, Shirish; Jadhav, Amol; Duraiswamy, B

    2016-02-01

    Gymnema sylvestre, important Indian traditional herbal medicine has been used for diabetes from several years and marketed as single or multi-herb formulations globally. People are consuming G.sylvestre along with conventional hypoglycemic drugs. Therefore, there is need of evidence based assessment of risk versus benefits when G.sylvestre co-administered with conventional oral hypoglycemic drugs. In present investigation, pharmacodynamics and pharmacokinetic interactions with oral hypoglycemic drug, glimepiride (GLM) was studied in streptozotocin (STZ) induced diabetic rats. A specific and rapid HPLC-ESI-MS/MS method was established for simultaneous quantification of GLM and gymnemagenin (GMG) in rat plasma. Pharmacokinetic and pharmacodynamic interaction studies were carried out in STZ induced diabetic rats after concomitant administration of 400mg/kg of G.sylvestre extract and 0.8mg/kg of GLM for 28 days. The developed HPLC-ESI-MS/MS method was rapid, specific, and precise. Con-comitant oral administration of G.sylvestre extract (400mg/kg) and GLM (0.8mg/kg) in diabetic rats for 28 days showed beneficial pharmacodynamic interactions whereas no major alterations in the pharmacokinetics parameters of GLM and GMG were observed. This interaction demonstrated in animal model implies that significant clinical outcome might occur during concomitant administration of G.sylvestre extract and GLM especially in diabetic patients and warrants further studies in the same set up. PMID:26721197

  6. ?-Caryophyllene, a natural sesquiterpene lactone attenuates hyperglycemia mediated oxidative and inflammatory stress in experimental diabetic rats.

    PubMed

    Basha, Rafeek Hidhayath; Sankaranarayanan, Chandrasekaran

    2016-02-01

    Oxidative and inflammatory stress has been implicated in the onset and progression of diabetes mellitus and its complications. The present study was designed to evaluate the effect of ?-Caryophyllene (BCP) on hyperglycemia mediated oxidative and inflammatory stress in streptozotocin (STZ) induced diabetic rats. Diabetes was induced in experimental rats by a single intraperitoneal injection of STZ (40mg/kg b.w.) dissolved in 0.1M citrate buffer (pH 4.5). Diabetic rats exhibited increased blood glucose with significant decrease in plasma insulin levels. The activities of antioxidant enzymes and the levels of non-enzymic antioxidants were decreased while increases in the levels of lipidperoxidative markers, protein carbonyls and conjugated dienes were observed in pancreatic tissues of diabetic rats. An elevation of proinflammatory cytokines tumor necrosis factor-? and interleukin-6 were observed in plasma and pancreatic tissues of diabetic rats. Intragastric administration of BCP (200mg/kg b.w) for 45 days significantly decreased glucose and increased insulin levels in diabetic rats. BCP administration significantly restored antioxidant status and decreased proinflammatory cytokines in diabetic rats. These findings were supported by histological and immunohistochemical studies. Thus, we conclude that oral administration of BCP effectively rescued ?-cells by mitigating hyperglycemia through enhancing insulin release and also averted oxidative/inflammatory stress in pancreatic tissue of diabetic rats. The efficacy of BCP was compared with glibenclamide, a standard antidiabetic drug. PMID:26748309

  7. Effects of aspirin and nimesulide on tissue damage in diabetic rats.

    PubMed

    Yesilot, Sukriye; Ozer, Mehmet Kaya; Bayram, Dilek; Oncu, Meral; Karabacak, Halil Ibrahim; Cicek, Ekrem

    2010-12-01

    This study was designed to compare the effect of Aspirin (AS) and Nimesulide (NM) on renal failure and vascular disorder in streptozotocin (STZ)-induced diabetic rats. Rats were divided into four groups; control, diabetic rats, diabetic rats plus AS and diabetic rats plus NM, which are COX inhibitors. The renal and aorta tissues morphology were investigated by light microscopy. Trunk blood was also obtained to determine plasma lipid peroxidation product malondialdehyde (MDA) and plasma activity of antioxidant enzymes. MDA levels were increased in the diabetic rats when compared to the control group. AS and NM administration caused a significant decrease in MDA production. Morphological damage in diabetic rats was severe in the kidney and in the aorta tissue. Treatment of AS reduced these damages, but NM did not exert positive effect on these damages in diabetic rats. As a result, although both AS and NM corrected lipid peroxidation parameters such as MDA via their antioxidant properties, only AS ameliorated pathological alteration in tissues. These findings indicate that there may be another mechanism in beneficial effect of AS in diabetic rats. PMID:20732820

  8. Antidiabetic and hypolipidemic activities of Kigelia pinnata flowers extract in streptozotocin induced diabetic rats

    PubMed Central

    Kumar, S; Kumar, V; Prakash, OM

    2012-01-01

    Objective To evaluate antidiabetic and hypolipidemic activities of Kigelia pinnata methanolic flowers extract in streptozotocin (STZ) induced diabetic wistar rat. Methods Rats were made diabetic by a single dose of STZ at 60 mg/kg body weight i.p. The blood glucose level was checked before and 72 h after STZ injection to confirm the development of diabetes. The flower extract and glibenclamide were administered orally at the doses of 250 and 500 mg/kg body weight for 21 days. Results Daily oral treatment with the extract and standard drug for 21 days significantly reduced blood glucose, serum cholesterol and triglycerides levels. High density lipoprotein-cholesterol level was found to be improved (P<0.01) as compared to diabetic control group. Conclusions It is concluded that Kigellia pinnata flowers extract have significant antidiabetic and hypolipidemic effect. PMID:23569967

  9. Antidiabetic effect of polysaccharides from Pleurotus ostreatus in streptozotocin-induced diabetic rats.

    PubMed

    Zhang, Yan; Hu, Tao; Zhou, Hongli; Zhang, Yang; Jin, Gang; Yang, Yu

    2016-02-01

    This study was performed to evaluate the effects of total polysaccharides extracted from Pleurotus ostreatus on type 2 diabetes. Rats were administered with high-fat diet and streptozotocin (STZ) to induce diabetes. The rats were then treated with 100, 200, and 400mg/kg/d POP or vehicle for 4 weeks. Our experiments indicated that POP reduces hyperglycemia and hyperlipidemia levels, improves insulin resistance, and increases glycogen storage by activating GSK3 phosphorylation and GLUT4 translocation. Moreover, POP reduces the risk of oxidative damage by increasing superoxide dismutase(SOD), catalase(CAT), and glutathione peroxidase(GSH-Px) activities and decreasing malonaldehyde(MDA) level. These results suggest that POP exerts antidiabetic effect on STZ-induced diabetic rats. PMID:26627601

  10. Canavanine activates imidazoline I-2 receptors to reduce hyperglycemia in type 1-like diabetic rats.

    PubMed

    Chang, Chin-Hong; Chao, Pin-Chun; Niu, Ho-Shan; Huang, Gin-Chi; Chen, Li-Jen; Cheng, Juei-Tang

    2015-10-01

    Canavanine is a guanidinium derivative that has the basic structure of a ligand for the imidazoline receptor (I-R). Furthermore, canavanine is found in an herb that has been shown to improve diabetic disorders. Thus, the present study was designed to investigate the anti-hyperglycemic action of canavanine in rats with streptozotocin (STZ)-induced type 1-like diabetes. Canavanine decreased hyperglycemia in the STZ-induced diabetic rats, and this action was blocked by the antagonist specific to imidazoline I-2 receptors (I-2R), BU224, in a dose-dependent manner. Additionally, canavanine increased the plasma ?-endorphin level, as measured using enzyme-linked immunosorbent assay (ELISA), and this increase was also blocked by BU224 in the same manner. Moreover, amiloride at a dose sufficient to block I-2AR attenuated the actions of canavanine, including the increased ?-endorphin level and the antihyperglycemic effect. Otherwise, canavanine increased the radioactive glucose uptake into skeletal muscles isolated from the diabetic rats. Furthermore, canavanine increased the phosphorylation of AMPK measured using Western blot analysis in these isolated skeletal muscles in a dose-dependent manner. Additionally, the insulin sensitivity of the diabetic rats was markedly increased by canavanine, and this action was also blocked by BU224. Overall, canavanine is capable of activating imidazoline I-2R; I-2AR is linked to an increase in the plasma level of ?-endorphin, and I-2BR is related to effects on the glucose uptake by skeletal muscle that reduces hyperglycemia in type 1-like diabetic rats. Therefore, canavanine can be developed as effective agent to treat the diabetic disorders in the future. PMID:26362499

  11. Lespedeza davurica (Lax.) Schindl. extract protects against cytokine-induced ?-cell damage and streptozotocin-induced diabetes.

    PubMed

    Sharma, Bhesh Raj; Rhyu, Dong Young

    2015-01-01

    Lespedeza has been used for the management of diabetes in folklore medicine. The purpose of this study is to investigate the protective effects of the methanol extract of Lespedeza davurica (LD) on cytokine-induced ?-cell damage and streptozotocin- (STZ-) induced diabetes. RINm5F cells were treated with interleukin- (IL-) 1? and interferon- (IFN-) ? to induce pancreatic ?-cell damage. The exposure of LD extract significantly decreased cell death, nitric oxide (NO) production, nitric oxide synthase (iNOS) expression, and nucleus factor-kappa B (NF-?B) p65 activation. Antidiabetic effects of LD extract were observed by oral glucose tolerance test (OGTT) in normal rats and by checking the biochemical, physiological, and histopathological parameters in STZ-induced diabetic rats. In OGTT, glucose clearance levels improved by oral treatment of LD extract. The water intake, urine volume, blood glucose, and serum TG, TC, TBARS, and DPP-IV levels were significantly decreased, and liver glycogen content was significantly increased by treatment of LD extract (250 mg/kg BW) in STZ-induced diabetic rats. Also, insulin immunoreactivity of the pancreases was increased in LD extract administrated rats compared with diabetic control rats. These results indicate that LD extract may protect pancreatic ?-cell damage and regulate the blood glucose in STZ-induced diabetic rats. PMID:25793188

  12. Antiarrhythmic effects and ionic mechanisms of allicin on myocardial injury of diabetic rats induced by streptozotocin.

    PubMed

    Huang, Wei; Wang, Ye; Cao, Yong-Gang; Qi, Han-Ping; Li, Lei; Bai, Bing; Liu, Yang; Sun, Hong-Li

    2013-08-01

    The aim of this study was to evaluate the antiarrhythmic effect of allicin (AL) on streptozotocin (STZ)-induced diabetic rats and explore the possible mechanisms. Hyperglycemia was induced in rats by single intraperitoneal injection of STZ (40 mg/kg). Three days after STZ treatment, the hyperglycemic rats (plasma glucose levels?16.7 mM) were administered with AL (4, 8, and 16 mg/kg) by intraperitoneal injection daily for 28 days. The fasting blood glucose levels were measured on every seventh day during the 28 days of treatment. The body weight and blood glucose levels were detected after 28 days. Antiarrhythmic effect of AL was observed in the diabetic rats induced by BaCl2. To determine the ionic mechanism in rat ventricular myocytes of AL, action potential duration (APD), L-type calcium current (ICa-L), and inward rectifier potassium current (IK1) were recorded by the whole cell-patch clamp technique. The expressions of L-type calcium channel protein ?1C mRNA and cell potassium channels protein Kir2.1 mRNA were studied by RT-PCR. AL normalized the RR interval and QT interval in diabetic rats. AL obviously delayed the onset of ventricular arrhythmia and reduced the score of arrhythmia induced by BaCl2. Electrophysiological experiment revealed that AL could shorten APD through inhibition of ICa-L and enhancement of IK1. RT-PCR analysis indicated that long-term treatment with AL could decrease the expression of ?1C mRNA and increase the expression of Kir2.1 mRNA. AL has antiarrhythmic effect in STZ-induced diabetic rats. It is tempting for the application of AL to be a useful therapeutic approach in diabetes with ventricular arrhythmia. PMID:23604291

  13. Studies on pyrazinoylguanidine. 5. Temporal effects over 24 weeks demonstrating attenuation of diabetic nephropathy in STZ-diabetic rats.

    PubMed

    Follansbee, M H; Beyer, K H; Griffith, J W; Vesell, E S

    1997-05-01

    This study was designed to determine whether pyrazinoylguanidine (PZG) can attenuate diabetic nephropathy in streptozotocin (STZ)-induced diabetic rats. Diabetes was induced within 1 week after a single intraperitoneal dose of STZ (45 mg/kg in 0.05 mol/l sodium citrate buffer). Diabetic rats were divided into five groups. Each group received by gavage for 24 weeks one of the following: vehicle (saline 10 ml/kg, b.i.d.), PZG (35 mg/kg, b.i.d.), captopril (15 mg/kg, b.i.d.), or hydrochlorothiazide (HCTZ, 20 mg/kg, b.i.d.). Insulin (NPH 7.5 U/day) was given subcutaneously. PZG treatment for 24 weeks reduced mortality and attenuated diabetic nephropathy, as indicated by reduced urinary excretion of total protein (79% of control), low-molecular-weight protein (12% of control), and albumin (60% of control). PZG also preserved renal structure and function. Compared to HCTZ or vehicle-treated rats, STZ-diabetic rats receiving either captopril or insulin exhibited decreased excretion of total protein, low-molecular-weight protein, and albumin, as well as amelioration of renal pathology. Collectively, these results indicate that PZG, as well as captopril and insulin, improved longevity and several indices of diabetic nephropathy in STZ-diabetic rats. PMID:9380770

  14. Ultrastructural Analysis of In Vivo Hypoglycemiant Effect of Two Polyoxometalates in Rats with Streptozotocin-Induced Diabetes.

    PubMed

    Blici, ?tefana; Wankeu-Nya, Modeste; Rusu, Dan; Nicula, Gheorghe Z; Rusu, Mariana; Florea, Adrian; Matei, Horea

    2015-10-01

    Two polyoxometalates (POMs), synthesized through a self-assembling method, were used in the treatment of streptozotocin (STZ)-induced diabetic rats. One of these nanocompounds [tris(vanadyl)-substituted tungsto-antimonate(III)-anionsPOM1] was previously described in the literature, whereas the second [tris-butyltin-21-tungsto-9-antimonate(III)-anionsPOM2], was prepared by us based on our original formula. In rats with STZ-induced diabetes treated with POMs (up to a cumulative dose of 4 mg/kg bodyweight at the end of the treatments), statistically significant reduced levels of blood glucose were measured after 3 weeks, as compared with the diabetic control groups (DCGs). Ultrastructural analysis of pancreatic ?-cells (including the mean diameter of secretory vesicles and of their insulin granules) in the treated diabetic rats proved the POMs contribute to limitation of cellular degeneration triggered by STZ, as well as to the presence of increased amounts of insulin-containing vesicles as compared with the DCG. The two POMs also showed hepatoprotective properties when ultrastructural aspects of hepatocytes in the experimental groups of rats were studied. Based on our in vivo studies, we concluded that the two POMs tested achieved hypoglycemiant effects by preventing STZ-triggered apoptosis of pancreatic ?-cells and stimulation of insulin synthesis. PMID:26343528

  15. Antidiabetic and antihyperlipidemic activities of a novel polyherbal formulation in high fat diet/streptozotocin induced diabetic rat model

    PubMed Central

    Subhasree, N.; Kamella, Ananthkumar; Kaliappan, Ilango; Agrawal, Aruna; Dubey, Govind Prasad

    2015-01-01

    Objective: To investigate the antidiabetic and antihyperlipidemic activities of polyherbal formulation (PHF) containing hydroalcoholic extracts of four plants namely Salacia oblonga, Salacia roxbhurgii, Garcinia indica and Lagerstroemia parviflora in streptozotocin (STZ)-induced diabetic rats by administering oral doses (200 and 400 mg/kg body weight). Materials and Methods: Animals were divided into diabetic and nondiabetic groups. Rats were fed with a high-fat diet (HFD) and induced with a single low dose of STZ (35 mg/kg) i.p. Diabetic rats were treated with formulation (200 and 400 mg/kg) and metformin 250 mg/kg. Blood glucose levels were measured using blood glucose test strips with ACCU CHEK glucometer. Lipid profile and gluconeogenic enzymes were determined in normal and STZ-induced diabetic rats after oral administration of the PHF for 28 days. Histopathological changes in diabetic rat organs (pancreas, liver, and kidney) were also observed after PHF treatment. Results: Treatment of diabetic rats with PHF and metformin decreased plasma glucose and lipid profile levels. Blood glucose level showed significant reduction after 28 days of treatment with formulation at 200 and 400 mg/kg and in metformin. Formulation treated rats showed significant (P < 0.001) decrease in the activities of gluconeogenic enzymes. Histological examination of various organ tissues of normal control, diabetic control, and drug-treated rats revealed significant results. Treatment with PHF reverses the most blood and tissue changes toward the normal level. Conclusion: These findings suggested the antihyperglycemic and antihyperlipidemic properties of the PHF and thus help in preventing future complications of diabetes. PMID:26600639

  16. Phosphatidylinositol-3-kinase is involved in the antihyperglycemic effect induced by resveratrol in streptozotocin-induced diabetic rats.

    PubMed

    Chi, Tzong-Cherng; Chen, Win-Pin; Chi, Tsung-Li; Kuo, Tzong-Fu; Lee, Shoei-Sheng; Cheng, Juei-Tang; Su, Ming-Jai

    2007-04-10

    Resveratrol, a polyphenolic substance found in grape skin, is proposed to account in part for the protective effect of red wine in the cardiovascular system. The aim of the present study is to investigate the action and possible mechanisms of resveratrol-produced regulation of plasma glucose in normal and diabetic rats including the animal model of streptozotocin (STZ)-induced and nicotinamide-STZ-induced (NA-STZ), and insulin-resistant diabetic rats. Resveratrol (p.o.) produced a hypoglycemic effect in a dose-dependent manner in normal and diabetic rats, and the insulin level was increased following resveratrol treatment in normal and NA-STZ diabetic rats. In insulin-deficient STZ-diabetic rats, resveratrol significantly lowered the plasma glucose 90 min after oral treatment, and the hypoglycemic effect was abolished by phosphatidyl-3-kinase (PI3K) inhibitors (LY294002 and wortmannin) which also inhibited resveratrol-induced Akt phosphorylation in soleus muscle of STZ-diabetic rats. The change in the protein expression level of glucose transporter subtype 4 (GLUT4) in the soleus muscle and phosphoenolpyruvate carboxykinase (PEPCK) in the liver of STZ-diabetic rats treated with resveratrol (3 mg/kg, p.o.) for 7 days was examined. Resveratrol normalized hepatic PEPCK expression and increased GLUT4 expression in the soleus muscle of STZ-diabetic rats. The results indicate that the mechanisms contributing to the hypoglycemic effect of resveratrol include insulin-dependent and insulin-independent pathway, and PI3K-Akt-signaling was involved in the latter mechanism to enhance glucose uptake in skeletal muscle. PMID:17346750

  17. Ameliorative Potentials of Ginger (Z. officinale Roscoe) on Relative Organ Weights in Streptozotocin induced Diabetic Rats

    PubMed Central

    Eleazu, C. O.; Iroaganachi, M.; Okafor, P. N.; Ijeh, I. I.; Eleazu, K. C.

    2013-01-01

    The ameliorating potentials of ginger incorporated feed (10%) on the relative organ weights of Streptozotocin (STZ) induced diabetic rats was investigated. The experiment lasted for three weeks. Results show that administration of 10% ginger feed to the diabetic rats of group 3, resulted in a 29.81% decrease in their resulting hyperglycemia with a corresponding amelioration of elevated urinary protein, sugars, specific gravity as well as renal growth. In addition, administration of the ginger incorporated feeds to the diabetic rats of group 3, resulted in 9.88% increase in body weight with a corresponding 60.24% increase in growth compared with the non-diabetic rats administered standard rat pellets that had 6.21% increase in weight with a corresponding 60.14% increase in growth unlike the diabetic control rats that recorded 28.62% decrease in body weight with a corresponding 239.9% decrease in growth rates. Analysis of the chemical composition of the flour of the ginger incorporated feed indicated that it contained moderate amounts of moisture, crude fibre, alkaloids, saponins, tannins, Fe and Zn but considerable amounts of proteins, lipids, carbohydrates, ash, flavonoids, calcium, magnesium, potassium, phosphorous and energy value. There was no significant difference (P>0.05) in the liver and relative liver weights of the diabetic control rats and the diabetic -ginger treated rats. In addition, there were no significant differences in the kidney weights of the non-diabetic, diabetic control and diabetic treated rats (P>0.05) while there were significant differences in the relative kidney weights of the non-diabetic rats and the diabetic rats treated with ginger feeds (P<0.05). Results show that the use of ginger in the dietary management of diabetes mellitus could be a breakthrough in the search for novel plants that could prevent the development of diabetic glomerular hypertrophy. PMID:23847458

  18. Ameliorative Potentials of Ginger (Z. officinale Roscoe) on Relative Organ Weights in Streptozotocin induced Diabetic Rats.

    PubMed

    Eleazu, C O; Iroaganachi, M; Okafor, P N; Ijeh, I I; Eleazu, K C

    2013-06-01

    The ameliorating potentials of ginger incorporated feed (10%) on the relative organ weights of Streptozotocin (STZ) induced diabetic rats was investigated. The experiment lasted for three weeks. Results show that administration of 10% ginger feed to the diabetic rats of group 3, resulted in a 29.81% decrease in their resulting hyperglycemia with a corresponding amelioration of elevated urinary protein, sugars, specific gravity as well as renal growth. In addition, administration of the ginger incorporated feeds to the diabetic rats of group 3, resulted in 9.88% increase in body weight with a corresponding 60.24% increase in growth compared with the non-diabetic rats administered standard rat pellets that had 6.21% increase in weight with a corresponding 60.14% increase in growth unlike the diabetic control rats that recorded 28.62% decrease in body weight with a corresponding 239.9% decrease in growth rates. Analysis of the chemical composition of the flour of the ginger incorporated feed indicated that it contained moderate amounts of moisture, crude fibre, alkaloids, saponins, tannins, Fe and Zn but considerable amounts of proteins, lipids, carbohydrates, ash, flavonoids, calcium, magnesium, potassium, phosphorous and energy value. There was no significant difference (P>0.05) in the liver and relative liver weights of the diabetic control rats and the diabetic -ginger treated rats. In addition, there were no significant differences in the kidney weights of the non-diabetic, diabetic control and diabetic treated rats (P>0.05) while there were significant differences in the relative kidney weights of the non-diabetic rats and the diabetic rats treated with ginger feeds (P<0.05). Results show that the use of ginger in the dietary management of diabetes mellitus could be a breakthrough in the search for novel plants that could prevent the development of diabetic glomerular hypertrophy. PMID:23847458

  19. GABA tea prevents cardiac fibrosis by attenuating TNF-alpha and Fas/FasL-mediated apoptosis in streptozotocin-induced diabetic rats.

    PubMed

    Cherng, Shur-Hueih; Huang, Chih-Yang; Kuo, Wei-Wen; Lai, Shue-Er; Tseng, Chien-Yu; Lin, Yueh-Min; Tsai, Fuu-Jen; Wang, Hsueh-Fang

    2014-03-01

    GABA tea is a tea product that contains a high level of gamma-aminobutyric acid (GABA). This study investigated the effects of GABA tea on the heart in a diabetic rat model. Male Wistar rats were injected with 55mg/kg streptozotocin (STZ) to induce diabetes for 2weeks and then orally given dosages of 4.55 and 45.5mg/kg/day GABA tea extract for 6weeks. The results revealed that fasting blood glucose levels returned to normal levels in GABA tea-treated diabetic rats, but not in the untreated diabetic rats. Additionally, GABA tea effectively inhibited cardiac fibrosis induced by STZ. Further experiments showed that the STZ-induced protein levels of tumor necrosis factor-alpha (TNF-alpha), Fas, activated caspase-8 and caspase-3 were significantly inhibited by the GABA tea treatment. Therefore, our data suggest that the inhibiting effect of GABA tea on STZ-induced cardiac fibrosis in diabetic rats may be mediated by reducing blood glucose and further attenuating TNF-alpha expression and/or Fas/Fas ligand (FasL)-mediated apoptosis. These findings will provide implications for the potential anti-diabetic properties of GABA tea. PMID:24374093

  20. Prevention and management of diabetic retinopathy in STZ diabetic rats by Tinospora cordifolia and its molecular mechanisms.

    PubMed

    Agrawal, Shyam S; Naqvi, Salma; Gupta, Suresh K; Srivastava, Sushma

    2012-09-01

    We investigated the potential of Tinospora cordifolia (TC) in treatment of diabetic retinopathy in STZ-induced rats due to its antihyperglycemic, angiogenic, antiinflammatory and antioxidant effects. The diabetic rats, treated for 24 weeks with TC extract (250 mg/kg), were evaluated for lenticular and fundus changes. Biochemical parameters were estimated and histopathological studies performed. TC significantly reduced blood glucose and glycated hemoglobin in treated rats. It prevented cataract development in treated group. Angiogenic markers VEGF and PKC increased in diabetic retina, which reduced significantly with TC. Anti-inflammatory parameters TNF-α and IL-1β elevated in diabetic group unlike that in treated group. TC also provided defense against depletion of antioxidant enzymes- glutathione and catalase. Histopathological studies revealed thickening of basement membrane of the retinal and glomerular vasculature of diabetic rat, but no basement membrane widening was seen in treated animals. Destruction of pancreatic islet structure was observed in diabetic group, but not in treated. Thus, TC reduces blood glucose and inhibits overexpression of angiogenic and inflammatory mediators, which are distinct markers of diabetic retinopathy. It also prevents retinal oxidative stress and restores antioxidant enzyme levels. These data provide evidence for the safety and potential effect of TC in the management of experimental diabetic retinopathy. PMID:22687550

  1. Protective Effect of Ethyl Acetate Fraction of Stereospermum Suaveolens Against Hepatic Oxidative Stress in STZ Diabetic Rats

    PubMed Central

    Balasubramanian, Thirumalaiswamy; Senthilkumar, G. P; Karthikeyan, M.; Chatterjee, Tapan Kumar

    2013-01-01

    Stereospermum suaveolens is a folk remedy for the treatment of diabetes and liver disorders in southern parts of India. In the present study, the protective effect of the ethyl acetate fraction of ethanol extract from S. suaveolens against hepatic oxidative stress was evaluated in streptozotocin (STZ)-induced diabetic rats for 14 days. The ethyl acetate fraction was administered orally to the STZ diabetic rats at the doses of 200 and 400 mg/kg. Blood glucose level was measured according to glucose oxidase method. In order to determine hepatoprotective activity, changes in the levels of serum biomarker enzymes such as aspartate transaminase (AST), alanine transaminase (ALT), and serum alkaline phosphatase (SALP) were assessed in the ethyl acetate fraction treated diabetic rats and were compared with the levels in diabetic control rats. In addition, the antioxidant activity of ethyl acetate fraction was evaluated using various hepatic parameters such as thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT). It was found that administration of ethyl acetate fraction (200 and 400 mg/kg) produced a significant (P < 0.001) fall in fasting blood glucose level, TBARS, bilirubin, AST, ALT, and SALP, while elevating the GSH levels, and SOD and CAT activities in diabetic rats. Histopathologic studies also revealed the protective effect of ethyl acetate fraction on the liver tissues of diabetic rats. It was concluded from this study that the ethyl acetate fraction from ethanol extract of S. suaveolens modulates the activity of enzymatic and nonenzymatic antioxidants and enhances the defense against hepatic oxidative stress in STZ-induced diabetic rats. PMID:24716175

  2. Chrysin, an anti-inflammatory molecule, abrogates renal dysfunction in type 2 diabetic rats

    SciTech Connect

    Ahad, Amjid; Ganai, Ajaz Ahmad; Mujeeb, Mohd; Siddiqui, Waseem Ahmad

    2014-08-15

    Diabetic nepropathy (DN) is considered as the leading cause of end-stage renal disease (ESRD) worldwide, but the current available treatments are limited. Recent experimental evidences support the role of chronic microinflammation in the development of DN. Therefore, the tumor necrosis factor-alpha (TNF-α) pathway has emerged as a new therapeutic target for the treatment of DN. We investigated the nephroprotective effects of chrysin (5, 7-dihydroxyflavone) in a high fat diet/streptozotocin (HFD/STZ)-induced type 2 diabetic Wistar albino rat model. Chrysin is a potent anti-inflammatory compound that is abundantly found in plant extracts, honey and bee propolis. The treatment with chrysin for 16 weeks post induction of diabetes significantly abrogated renal dysfunction and oxidative stress. Chrysin treatment considerably reduced renal TNF-α expression and inhibited the nuclear transcription factor-kappa B (NF-kB) activation. Furthermore, chrysin treatment improved renal pathology and suppressed transforming growth factor-beta (TGF-β), fibronectin and collagen-IV protein expressions in renal tissues. Chrysin also significantly reduced the serum levels of pro-inflammatory cytokines, interleukin-1beta (IL-1β) and IL-6. Moreover, there were no appreciable differences in fasting blood glucose and serum insulin levels between the chrysin treated groups compared to the HFD/STZ-treated group. Hence, our results suggest that chrysin prevents the development of DN in HFD/STZ-induced type 2 diabetic rats through anti-inflammatory effects in the kidney by specifically targeting the TNF-α pathway. - Highlights: • Chrysin reduced renal oxidative stress and inflammation in diabetic rats. • Chrysin reduced serum levels of pro-inflammatory in diabetic rats. • Chrysin exhibited renal protective effect by suppressing the TNF-α pathway.

  3. Effects of ursolic acid derivatives on Caco-2 cells and their alleviating role in streptozocin-induced type 2 diabetic rats.

    PubMed

    Wu, Panpan; He, Ping; Zhao, Suqing; Huang, Tianming; Lu, Yujing; Zhang, Kun

    2014-01-01

    In this study, the effect and mechanism of a series of ursolic acid (UA) derivatives on glucose uptake were investigated in a Caco-2 cells model. Their effect on hyperglycemia, hyperlipidemia and oxidative stress were also demonstrated in streptozocin (STZ)-induced diabetic rats. 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-glucose (2-NBDG) was used as a fluorescein in Caco-2 cells model to screen UA derivatives by glucose uptake and expression of glucose transporter protein (SGLT-1, GLUT-2). Moreover, STZ-induced diabetic rats were administered with these derivatives for 4 weeks of treatment. The fasting blood glucose (FBG), insulin levels, biochemical parameters, lipid levels, and oxidative stress markers were finally evaluated. The results of this study indicated that compounds 10 and 11 significantly inhibited 2-NBDG uptake under both Na+-dependent and Na+-independent conditions by decreasing SGLT-1 and GLUT-2 expression in the Caco-2 cells model. Further in vivo studies revealed that compound 10 significantly reduced hyperglycemia by increasing levels of serum insulin, total protein, and albumin, while the fasting blood glucose, body weight and food intake were restored much closer to those of normal rats. Compounds 10 and 11 showed hypolipidemic activity by decreasing the total amounts of cholesterol (TC) and triglycerides (TG). Furthermore, compound 10 showed antioxidant potential which was confirmed by elevation of glutathione (GSH) and superoxide dismutase (SOD) and reduction of malondialdehyde (MDA) levels in the liver and kidney of diabetic rats. It was concluded that compound 10 caused an apparent inhibition of intestinal glucose uptake in Caco-2 cells and hypoglycemia, hypolipidemia and augmented oxidative stress in STZ-induced diabetic rats. Thus, compound 10 could be developed as a potentially complementary therapeutic or prophylactic agent for diabetics mellitus and its complications. PMID:25153871

  4. Improvement of glycemic control in streptozotocin-induced diabetic rats by Atlantic salmon skin gelatin hydrolysate as the dipeptidyl-peptidase IV inhibitor.

    PubMed

    Hsieh, C H; Wang, T Y; Hung, C C; Chen, M C; Hsu, K C

    2015-06-01

    In our previous study, Atlantic salmon skin gelatin hydrolysed with flavourzyme possessed 42.5% dipeptidyl-peptidase (DPP)-IV inhibitory activity at a concentration of 5 mg mL(-1). The oral administration of the hydrolysate (FSGH) at a single dose of 300 mg per day in streptozotocin (STZ)-induced diabetic rats for 5 weeks was evaluated for its antidiabetic effect. During the 5-week experiment, body weight increased, and the food and water intake was reduced by FSGH in diabetic rats. The daily administration of FSGH for 5 weeks was effective for lowering the blood glucose levels of diabetic rats during an oral glucose tolerance test (OGTT). After the 5-week treatment, plasma DPP-IV activity was inhibited; the plasma activity of glucagon-like peptide-1 (GLP-1), insulin, and the insulin-to-glucagon ratio were increased by FSGH in diabetic rats. The results indicate that FSGH has the function of inhibiting GLP-1 degradation by DPP-IV, resulting in the enhancement of insulin secretion and improvement of glycemic control in STZ-induced diabetic rats. PMID:25946069

  5. Evaluation of the hypoglycemic and hypolipidemic effects of an ethylacetate fraction of Artocarpus heterophyllus (jak) leaves in streptozotocin-induced diabetic rats

    PubMed Central

    Chackrewarthy, S.; Thabrew, M. I.; Weerasuriya, M. K. B.; Jayasekera, S.

    2010-01-01

    Aqueous extracts of mature leaves of Artocarpus heterophyllus (jak) are used by traditional medical practitioners in Sri Lanka and India for the treatment of diabetes. This study was conducted to investigate the hypoglycemic and hypolipidemic effects of an ethylacetate (EA) fraction of the mature leaves of A. heterophyllus in a streptozotocin (STZ) induced diabetic rat model. In normoglycemic rats, administration of a single dose (20 mg/kg) of the EA fraction resulted in a significant (P < 0.05) reduction in the fasting blood glucose concentration and a significant improvement in glucose tolerance (P < 0.05), compared to the controls. In STZ-induced diabetic rats, chronic administration of the EA fraction of A. heterophyllus leaves daily for 5 weeks resulted in a significant lowering of serum glucose, cholesterol and triglyceride (TG) levels. Compared to control diabetic rats, the extract-treated rats had 39% less serum glucose, 23% lower serum total cholesterol and 40% lower serum TG levels and 11% higher body weight at the end of the fifth week. The percentage reductions in the serum parameters mediated by the test fraction were comparable with those produced by glibenclamide (0.6 mg/kg), the reference drug used in this study. It can be concluded that the EA fraction of A. heterophyllus leaves contains one or more hypoglycemic and hypolipidemic principles which have the potential to be developed further for the treatment of diabetes specifically associated with a hyperlipidemic state. PMID:20931077

  6. Opposite Expression of SPARC between the Liver and Pancreas in Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Aseer, Kanikkai Raja; Kim, Sang Woo; Choi, Myung-Sook; Yun, Jong Won

    2015-01-01

    Secreted protein acidic and rich in cysteine (SPARC) is a matricellular protein that regulates several cellular events, including inflammation and tissue remodelling. In this study, we investigated the tissue-specific expression of SPARC in streptozotocin (STZ)-induced diabetes, and found that SPARC was significantly up-regulated in the liver while down-regulated in the pancreas of STZ-induced diabetic rats. Chronic inflammation occurred in the diabetic pancreas accompanied by up-regulation of CCAAT/enhancer-binding protein beta (C/EBP?) and its targets (TNF?, Il6, CRP, and Fn1) as well as myeloperoxidase (Mpo) and C-X-C chemokine receptor type 2 (Cxcr2). Diabetic liver showed significant up-regulation of Tgfb1 as well as moderately less up-regulated TNF? and reduced Fn1, resulting in elevated fibrogenesis. PARP-1 was not up-regulated during CD95-mediated apoptosis, resulting in restoration of high ATP levels in the diabetic liver. On the contrary, CD95-dependent apoptosis was not observed in the diabetic pancreas due to up-regulation of PARP-1 and ATP depletion, resulting in necrosis. The cytoprotective machinery was damaged by pancreatic inflammation, whereas adequate antioxidant capacity indicates low oxidative stress in the diabetic liver. High and low cellular insulin content was found in the diabetic liver and pancreas, respectively. Furthermore, we identified six novel interacting partner proteins of SPARC by co-immunoprecipitation in the diabetic liver and pancreas, and their interactions with SPARC were predicted by bioinformatics tools. Taken together, opposite expression of SPARC in the diabetic liver and pancreas may be related to inflammation and immune cell infiltration, degrees of apoptosis and fibrosis, cytoprotective machinery, and cellular insulin levels. PMID:26110898

  7. Neuroprotective effect of RYGB in Zucker fatty diabetic rats

    PubMed Central

    Han, Xin-Sheng; Huang, Yong; Jing, Hong-Jian; Zhang, Ai-Wu; Jiang, Tao; Xu, Yu-Ming

    2014-01-01

    The aim of this study is to explore the therapeutic potential of RYGB, a common used bariatric surgery, on diabetic polyneuropathy (DPN) in streptozotocin (STZ)-induced diabetic rats. In animal model experiments, rats were made diabetic by STZ administration, and after 12 weeks of diabetes, two groups were studied: RYGB and sham surgery control (PF). Change in oral glucose tolerance, insulin sensitivity, and the plasma concentrations of insulin, glucagon, glucagon-like peptide-1 (GLP-1) were measured. Peripheral nerve function was determined by the current perception threshold. Sciatic nerve blood flow (SNBF) and intraepidermal nerve fiber densities (IENFDs) also were evaluated. The results indicated that glucose tolerance and insulin sensitivity were significantly improved in the RYGB group. Fasting total GLP-1 were increased in the RYGB group. The increase seen in current perception threshold vales in RYGB group was reduced. The decreased IENFDs in sole skins of RYGB group were ameliorated by RYGB. In conclusion, the findings indicate that RYGB ameliorates the severity of DPN, which may be associated with increased GLP-1 and improved insulin sensitivity/action. PMID:25419361

  8. Cardioprotective Activity of Pongamia pinnata in Streptozotocin-Nicotinamide Induced Diabetic Rats.

    PubMed

    Badole, Sachin L; Chaudhari, Swapnil M; Jangam, Ganesh B; Kandhare, Amit D; Bodhankar, Subhash L

    2015-01-01

    Pongamia pinnata (L.) Pierre has been used in traditional medicine for the treatment for diabetes and metabolic disorder. The aim of this study was to investigate the effect of petroleum ether extract of the stem bark of P. pinnata (known as PPSB-PEE) on cardiomyopathy in diabetic rats. Diabetes was induced in overnight fasted Sprague-Dawley rats by using injection of streptozotocin (55 mg/kg, i.p.). Nicotinamide (100 mg/kg, i.p.) was administered 20 min before administration of streptozotocin. Rats were divided into group I: nondiabetic, group II: diabetic control (tween 80, 2%; 10 mL/kg, p.o.) as vehicle, and group III: PPSB-PEE (100 mg/kg, p.o.). The blood glucose level, ECG, hemodynamic parameters, cardiotoxic and antioxidant biomarkers, and histology of heart were carried out after 4 months after STZ with nicotinamide injection. PPSB-PEE treatment improved the electrocardiographic, hemodynamic changes; LV contractile function; biological markers; oxidative stress parameters; and histological changes in STZ induced diabetic rats. PPSB-PEE (100 mg/kg, p.o.) decreased blood glucose level, improved electrocardiographic parameters (QRS, QT, and QTc intervals) and hemodynamic parameters (SBP, DBP, EDP, max dP/dt, contractility index, and heart rate), controlled levels of cardiac biomarkers (CK-MB, LDH, and AST), and improved oxidative stress (SOD, MDA, and GSH) in diabetic rats. PPSB-PEE is a promising remedy against cardiomyopathy in diabetic rats. PMID:25954749

  9. Decrease of PPAR? in Type-1-Like Diabetic Rat for Higher Mortality after Spinal Cord Injury

    PubMed Central

    Tsai, Cheng-Chia; Lee, Kung-Shing; Chen, Sheng-Hsien; Chen, Li-Jen; Liu, Keng-Fan; Cheng, Juei-Tang

    2014-01-01

    Changes in the peroxisome proliferator-activated receptors-? (PPAR?) expression in rats after spinal cord injury (SCI) have been previously reported. Diabetic animals show a higher mortality after SCI. However, the relationship between the progress of diabetes and PPAR? in SCI remains unknown. In the present study, we used compressive SCI in streptozotocin-(STZ-) induced diabetic rats. GW0742, a PPAR? agonist, was used to evaluate its merit in STZ rats after SCI. Changes in PPAR? expression were detected by Western blot. Survival rates were also estimated. A lower expression of PPAR? in spinal cords of STZ-diabetic rats was observed. In addition, the survival times in two-week induction diabetes were longer than those in eight-week induction group, which is consistent with the expression of PPAR? in the spinal cord. Moreover, GW0742 significantly increased the survival time of STZ rats. Furthermore, their motor function and pain response were attenuated by GSK0660, a selective PPAR? antagonist, but were enhanced by GW0742. In conclusion, the data suggest that higher mortality rate in STZ-diabetic rats with SCI is associated with the decrease of PPAR? expression. Thus, change of PPAR? expression with the progress of diabetes seems responsible for the higher mortality rate after SCI. PMID:24817882

  10. Cardioprotective Activity of Pongamia pinnata in Streptozotocin-Nicotinamide Induced Diabetic Rats

    PubMed Central

    Badole, Sachin L.; Chaudhari, Swapnil M.; Jangam, Ganesh B.; Kandhare, Amit D.; Bodhankar, Subhash L.

    2015-01-01

    Pongamia pinnata (L.) Pierre has been used in traditional medicine for the treatment for diabetes and metabolic disorder. The aim of this study was to investigate the effect of petroleum ether extract of the stem bark of P. pinnata (known as PPSB-PEE) on cardiomyopathy in diabetic rats. Diabetes was induced in overnight fasted Sprague-Dawley rats by using injection of streptozotocin (55 mg/kg, i.p.). Nicotinamide (100 mg/kg, i.p.) was administered 20 min before administration of streptozotocin. Rats were divided into group I: nondiabetic, group II: diabetic control (tween 80, 2%; 10 mL/kg, p.o.) as vehicle, and group III: PPSB-PEE (100 mg/kg, p.o.). The blood glucose level, ECG, hemodynamic parameters, cardiotoxic and antioxidant biomarkers, and histology of heart were carried out after 4 months after STZ with nicotinamide injection. PPSB-PEE treatment improved the electrocardiographic, hemodynamic changes; LV contractile function; biological markers; oxidative stress parameters; and histological changes in STZ induced diabetic rats. PPSB-PEE (100 mg/kg, p.o.) decreased blood glucose level, improved electrocardiographic parameters (QRS, QT, and QTc intervals) and hemodynamic parameters (SBP, DBP, EDP, max dP/dt, contractility index, and heart rate), controlled levels of cardiac biomarkers (CK-MB, LDH, and AST), and improved oxidative stress (SOD, MDA, and GSH) in diabetic rats. PPSB-PEE is a promising remedy against cardiomyopathy in diabetic rats. PMID:25954749

  11. Genistein ameliorates cardiac inflammation and oxidative stress in streptozotocin-induced diabetic cardiomyopathy in rats.

    PubMed

    Gupta, Suresh K; Dongare, Shirish; Mathur, Rajani; Mohanty, Ipseeta Ray; Srivastava, Sushma; Mathur, Sandeep; Nag, Tapas C

    2015-10-01

    The present study was undertaken to evaluate the protective effects of genistein against cardiac inflammation and oxidative stress in streptozotocin (STZ) (45 mg/kg body weight)-induced diabetic rats. genistein (300 mg/kg/day) was administered orally for 24 weeks to STZ-induced diabetic rats. The effects of genistein on blood glucose, % glycosylated hemoglobin (HbA1c), C-reactive protein, tumor necrosis factor (TNF- ?), transforming growth factor (TGF-?1), and total antioxidant were studied. Ultrastructural and histopathological assessment of injury were also undertaken using transmission electron microscope. STZ-induced diabetes resulted in significant increase in the levels of blood glucose, HbA1c, C-reactive protein, TNF- ? and TGF-?1, and a decline in total antioxidant reserve of the myocardium. Administration of genistein to diabetic rats resulted in a decrease in blood glucose (p < 0.001), % HbA1c (p < 0.0001), C-reactive protein (p < 0.001), and expression of TNF- ? (p < 0.001) and TGF-?1 (p < 0.0001) proteins. In addition, genistein treatment results in augmentation of total antioxidant (p < 0.01) reserve of the hearts. The above findings were supported by histological as well as immunohistochemical localization of NF-?B (p65) in the heart. Genistein treatment ameliorated the ultrastructural degenerative changes in the cardiac tissues as compared to the diabetic control. The result demonstrates that genistein restored the integrity of the diabetic myocardium by virtue of its anti-inflammatory and antioxidant effects. PMID:26092427

  12. Cerebrolysin Ameloriates Cognitive Deficits in Type III Diabetic Rats

    PubMed Central

    Georgy, Gehan S.; Nassar, Noha N.; Mansour, Hanaa A.; Abdallah, Dalaal M.

    2013-01-01

    Cerebrolysin (CBL), a mixture of several active peptide fragments and neurotrophic factors including brain-derived neurotrophic factor (BDNF), is currently used in the management of cognitive alterations in patients with dementia. Since Cognitive decline as well as increased dementia are strongly associated with diabetes and previous studies addressed the protective effect of BDNF in metabolic syndrome and type 2 diabetes; hence this work aimed to evaluate the potential neuroprotective effect of CBL in modulating the complications of hyperglycaemia experimentally induced by streptozotocin (STZ) on the rat brain hippocampus. To this end, male adult Sprague Dawley rats were divided into (i) vehicle- (ii) CBL- and (iii) STZ diabetic-control as well as (iv) STZ+CBL groups. Diabetes was confirmed by hyperglycemia and elevated glycated haemoglobin (HbA1c%), which were associated by weight loss, elevated tumor necrosis factor (TNF)-α and decreased insulin growth factor (IGF)-1β in the serum. Uncontrolled hyperglycemia caused learning and memory impairments that corroborated degenerative changes, neuronal loss and expression of caspase (Casp)-3 in the hippocampal area of STZ-diabetic rats. Behavioral deficits were associated by decreased hippocampal glutamate (GLU), glycine, serotonin (5-HT) and dopamine. Moreover, diabetic rats showed an increase in hippocampal nitric oxide and thiobarbituric acid reactive substances versus decreased non-protein sulfhydryls. Though CBL did not affect STZ-induced hyperglycemia, it partly improved body weight as well as HbA1c%. Such effects were associated by enhancement in both learning and memory as well as apparent normal cellularity in CA1and CA3 areas and reduced Casp-3 expression. CBL improved serum TNF-α and IGF-1β, GLU and 5-HT as well as hampering oxidative biomarkers. In conclusion, CBL possesses neuroprotection against diabetes-associated cerebral neurodegeneration and cognitive decline via anti-inflammatory, antioxidant and antiapototic effects. PMID:23840309

  13. Acute and subchronic antihyperglycemic activities of Bowdichia virgilioides roots in non-diabetic and diabetic rats

    PubMed Central

    Silva, Ana Carolina Mazei; dos Santos, Maísa Pavani; de França, Suélem Aparecida; da Silva, Virginia Claudia; da Silva, Luiz Everson; de Figueiredo, Uir Santana; Dall’Oglio, Evandro Luiz; Júnior, Paulo Teixeira de Sousa; Lopes, Carbene França; Baviera, Amanda Martins; Kawashita, Nair Honda

    2015-01-01

    Aim: The present study was undertaken to evaluate the acute and subchronic antihyperglycemic effects of methanolic extract of Bowdichia virgilioides root bark of B. virgilioides in streptozotocin (STZ)-induced diabetic rats. Materials and Methods: The extract (100, 250 or 500 mg/kg) was orally administered to male Wistar diabetic (STZ, 42 mg/kg i.v.) and non-diabetic rats into two main protocols: (i) subchronic experiments, where animals were treated for 21 days with B. virgilioides extract and the following parameters were evaluated: Body weight, fluid and food intake (determined daily), urinary glucose and urea (every 3 days) and glycemia (every 5 days). At the end of the experimental period, skeletal muscles (extensor digitorum longus [EDL] and soleus), retroperitoneal and epididymal white adipose tissues were collected and weighed; liver samples were used for the determination of the lipid and glycogen contents; (ii) acute experiments, which evaluated the alterations on fasting and post-prandial glycemia and on glucose tolerance using the oral glucose tolerance test (OGTT). Results: In subchronic experiments, the treatment with B. virgilioides extract did not change any parameter evaluated in diabetic and non-diabetic animals. On fasting and post-prandial glycemia, the extract treatment did not promote changes in the glycemia values in diabetic or non-diabetic animals. In OGTT, the treatment with 500 mg/kg B. virgilioides extract reduced the hyperglycemia peak after a glucose overload, when compared with non-treated diabetic animals, resulting in a lower area under curve. Conclusion: The results of our work indicate that B. virgilioides root extract promotes an acute antihyperglycemic effect in STZ-diabetic rats; this effect probably occurs through an inhibition of the intestinal glucose absorption. The continuity of the research is necessary to elucidate these possibilities. PMID:26401386

  14. Intracellular signalling pathways associated with the glucose-lowering effect of ST36 electroacupuncture in streptozotocin-induced diabetic rats

    PubMed Central

    Tzeng, Chung-Yuh; Lee, Yu-Chen; Ho, Tin-Yun; Chen, Ying-I; Hsu, Tai-Hao; Lin, Jaung-Geng; Lee, Kuan-Rong; Chang, Shih-Liang

    2015-01-01

    Background and aim Previous animal studies have reported a glucose-lowering effect of electroacupuncture (EA) and suggested that the mechanisms are closely related to intracellular signalling pathways. The aim of this study was to screen for potential intracellular signalling pathways that are upregulated by EA at ST36 bilaterally in rats with diabetes mellitus (DM) using microarray analysis. Methods Streptozotocin (STZ)-induced diabetic rats were randomly assigned to experimental (EA, n=8) or control (non-EA, n=8) groups. Plasma glucose levels were measured at baseline and after 30 and 60 min, and microarray analysis was performed on samples of gastrocnemius muscle. Results Relative to baseline values, EA significantly reduced plasma levels of glucose at 30 and 60 min. The microarray pathway analysis showed that cell adhesion molecules and type 1 DM gene sets were both upregulated in EA versus non-EA groups (p<0.05). Conclusions Cell adhesion molecules might be related to the glucose-lowering effect induced by EA in rats with STZ-induced type 1 diabetes. Further research will be required to examine the involvement of related intracellular signalling pathways. PMID:26025382

  15. Impairment of spinal cord conduction velocity in diabetic rats.

    PubMed

    Carsten, R E; Whalen, L R; Ishii, D N

    1989-06-01

    Peripheral neuropathy is a common and well-studied complication of diabetes mellitus, but the possibility that central neuropathy is also present has received scant attention. Based on recent evidence showing that insulin has a direct effect on axon formation and neuronal survival in vitro, it was predicted that functional neuropathy would be present in the spinal cord of diabetic animals. Although structural lesions are encountered in the spinal cord of diabetic patients at autopsy, the functional corollaries have essentially remained unstudied. We used a new procedure to study evoked spinal cord potentials in the rat, which revealed a significant retardation in conduction velocity in streptozocin (STZ)-induced diabetic animals. This retardation was not due to a toxic effect of STZ on the involved spinal cord sensory pathways, because insulin infusion prevented the development of spinal cord neuropathy. The kinetics and magnitude of decline in conduction velocity were similar in the spinal cord, saphenous nerve, and common peroneal nerve during the first 2 wk, suggesting that a common mechanism was involved. After 10 wk, a spontaneous improvement in function was observed in the spinal cord and common peroneal nerve but not in the saphenous nerve. Our results support the hypothesis that central nervous system dysfunction can occur along with peripheral sensory neuropathy in diabetes. PMID:2656342

  16. Effect of dragon fruit extract on oxidative stress and aortic stiffness in streptozotocin-induced diabetes in rats

    PubMed Central

    Anand Swarup, Kolla R. L.; Sattar, Munavvar A.; Abdullah, Nor A.; Abdulla, Mohammed H.; Salman, Ibrahim M.; Rathore, Hassaan A.; Johns, Edward J.

    2010-01-01

    Cardiovascular complications are consistently observed in diabetic patients across all age groups. The objective of the present study was to investigate the effect of aqueous extract of the fruit pulp of Hylocereus undatus (DFE) on aortic stiffness and oxidative stress in streptozotocin (STZ)-induced diabetes in rats. Twenty-four male, Sprague-Dawley rats were randomized into four groups: I (control), II (diabetic), III (DFE, 250 mg/kg) and IV (DFE 500 mg/kg). Diabetes was induced in groups II, III and IV by intraperitoneal (i.p.) injection of STZ (40 mg/kg). After confirmation of diabetes, group III and IV received DFE for 5 weeks. Pulse wave velocity (PWV) was used as a marker of aortic stiffness and was determined at the end of 5 weeks. DFE significantly decreased (P < 0.05) the fasting blood glucose levels in diabetic rats, but not to normal levels. Systolic blood pressure, pulse pressure and PWV were significantly increased (P < 0.05) in diabetic rats at the end of 5 weeks in comparison with control group. DFE treatment significantly decreased (P < 0.05) these elevations. Oxidative damage was observed in group II after 5 weeks. Plasma malondialdehyde levels significantly decreased (P < 0.05), while superoxide dismutase and total antioxidant capacity significantly increased (P < 0.05) with DFE treatment in comparison with group II. These data demonstrate that DFE treatment was effective in controlling oxidative damage and decreasing the aortic stiffness measured by PWV in STZ-induced diabetes in rats. PMID:21808536

  17. Effect of dragon fruit extract on oxidative stress and aortic stiffness in streptozotocin-induced diabetes in rats.

    PubMed

    Anand Swarup, Kolla R L; Sattar, Munavvar A; Abdullah, Nor A; Abdulla, Mohammed H; Salman, Ibrahim M; Rathore, Hassaan A; Johns, Edward J

    2010-01-01

    Cardiovascular complications are consistently observed in diabetic patients across all age groups. The objective of the present study was to investigate the effect of aqueous extract of the fruit pulp of Hylocereus undatus (DFE) on aortic stiffness and oxidative stress in streptozotocin (STZ)-induced diabetes in rats. Twenty-four male, Sprague-Dawley rats were randomized into four groups: I (control), II (diabetic), III (DFE, 250 mg/kg) and IV (DFE 500 mg/kg). Diabetes was induced in groups II, III and IV by intraperitoneal (i.p.) injection of STZ (40 mg/kg). After confirmation of diabetes, group III and IV received DFE for 5 weeks. Pulse wave velocity (PWV) was used as a marker of aortic stiffness and was determined at the end of 5 weeks. DFE significantly decreased (P < 0.05) the fasting blood glucose levels in diabetic rats, but not to normal levels. Systolic blood pressure, pulse pressure and PWV were significantly increased (P < 0.05) in diabetic rats at the end of 5 weeks in comparison with control group. DFE treatment significantly decreased (P < 0.05) these elevations. Oxidative damage was observed in group II after 5 weeks. Plasma malondialdehyde levels significantly decreased (P < 0.05), while superoxide dismutase and total antioxidant capacity significantly increased (P < 0.05) with DFE treatment in comparison with group II. These data demonstrate that DFE treatment was effective in controlling oxidative damage and decreasing the aortic stiffness measured by PWV in STZ-induced diabetes in rats. PMID:21808536

  18. Transcriptomic Analysis in Diabetic Nephropathy of Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Lomas-Soria, Consuelo; Ramos-Gmez, Minerva; Guevara-Olvera, Lorenzo; Guevara-Gonzlez, Ramn; Torres-Pacheco, Irineo; Gallegos-Corona, Marco A.; Reynoso-Camacho, Rosala

    2011-01-01

    Diabetic nephropathy (DN) is a major complication of diabetes and is caused by an imbalance in the expression of certain genes that activate or inhibit vital cellular functions of kidney. Despite several recent advances, the pathogenesis of DN remains far from clear, suggesting the need to carry out studies identifying molecular aspects, such as gene expression, that could play a key role in the development of DN. There are several techniques to analyze transcriptome in living organisms. In this study, the suppression subtractive hybridization (SSH) method was used to generate up- and down-regulated subtracted cDNA libraries in the kidney of streptozotocin (STZ)-induced diabetic rats. Northern-blot analysis was used to confirm differential expression ratios from the obtained SSH clones to identify genes related to DN. 400 unique SSH clones were randomly chosen from the two subtraction libraries (200 of each) and verified as differentially expressed. According to blast screening and functional annotation, 20.2% and 20.9% of genes were related to metabolism proteins, 9% and 3.6% to transporters and channels, 16% and 6.3% to transcription factors, 19% and 17.2% to hypothetical proteins, and finally 24.1 and 17.2% to unknown genes, from the down- and up-regulated libraries, respectively. The down- and up-regulated cDNA libraries differentially expressed in the kidney of STZ diabetic rats have been successfully constructed and some identified genes could be highly important in DN. PMID:22272082

  19. Decreased autophosphorylation of EGF receptor in insulin-deficient diabetic rats

    SciTech Connect

    Okamoto, M.; Kahn, C.R.; Maron, R.; White, M.F. )

    1988-04-01

    The authors have previously reported that despite an increase in receptor concentration, there is a decrease in autophosphorylation and tyrosine kinase activity of the insulin receptor in insulin-deficient diabetic rats. To determine if other tyrosine kinases might be altered, they have studied the epidermal growth factor (EGF) receptor kinase in wheat germ agglutinin-purified, Triton X-100-solubilized liver membranes from streptozotocin (STZ)-induced diabetic rats and the insulin-deficient BB rat. They find that autophosphorylation of EGF receptor is decreased in proportion to the severity of the diabetic state in STZ rats with a maximal decrease of 67%. A similar decrease in autophosphorylation was observed in diabetic BB rats that was partially normalized by insulin treatment. Separation of tryptic phosphopeptides by reverse-phase high-performance liquid chromatography revealed a decrease in labeling at all sites of autophosphorylation. A parallel decrease in EGF receptor phosphorylation was also found by immunoblotting with an antiphosphotyrosine antibody. EGF receptor concentration, determined by Scatchard analysis of {sup 125}I-labeled EGF binding, was decreased by 39% in the STZ rat and 27% in the diabetic BB rat. Thus autophosphorylation of EGF receptor, like that of the insulin receptor, is decreased in insulin-deficient rat liver. In the case of EGF receptor, this is due in part to a decrease in receptor number and in part to a decrease in the specific activity of the kinase.

  20. Brain Aging and AD-Like Pathology in Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Wang, Jian-Qin; Yin, Jie; Song, Yan-Feng; Zhang, Lang; Ren, Ying-Xiang; Wang, De-Gui; Gao, Li-Ping; Jing, Yu-Hong

    2014-01-01

    Objective. Numerous epidemiological studies have linked diabetes mellitus (DM) with an increased risk of developing Alzheimer's disease (AD). However, whether or not diabetic encephalopathy shows AD-like pathology remains unclear. Research Design and Methods. Forebrain and hippocampal volumes were measured using stereology in serial coronal sections of the brain in streptozotocin- (STZ-) induced rats. Neurodegeneration in the frontal cortex, hypothalamus, and hippocampus was evaluated using Fluoro-Jade C (FJC). A? aggregation in the frontal cortex and hippocampus was tested using immunohistochemistry and ELISA. Dendritic spine density in the frontal cortex and hippocampus was measured using Golgi staining, and western blot was conducted to detect the levels of synaptophysin. Cognitive ability was evaluated through the Morris water maze and inhibitory avoidant box. Results. Rats are characterized by insulin deficiency accompanied with polydipsia, polyphagia, polyuria, and weight loss after STZ injection. The number of FJC-positive cells significantly increased in discrete brain regions of the diabetic rats compared with the age-matched control rats. Hippocampal atrophy, A? aggregation, and synapse loss were observed in the diabetic rats compared with the control rats. The learning and memory of the diabetic rats decreased compared with those of the age-matched control rats. Conclusions. Our results suggested that aberrant metabolism induced brain aging as characterized by AD-like pathologies. PMID:25197672

  1. L-glutamine supplementation prevents the development of experimental diabetic cardiomyopathy in streptozotocin-nicotinamide induced diabetic rats.

    PubMed

    Badole, Sachin L; Jangam, Ganesh B; Chaudhari, Swapnil M; Ghule, Arvindkumar E; Zanwar, Anand A

    2014-01-01

    The objective of the present investigation was to evaluate the effect of L-glutamine on cardiac myopathy in streptozotocin-nicotinamide induced diabetic rats. Diabetes was induced in overnight fasted Sprague Dawely rats by using intraperitonial injection of streptozotocin (55 mg/kg). Nicotinamide (100 mg/kg, i.p.) was administered 20 min before administration of streptozotocin. Experimental rats were divided into Group I: non-diabetic control (distilled water; 10 ml/kg, p.o.), II: diabetic control (distilled water, 10 ml/kg, p.o.), III: L-glutamine (500 mg/kg, p.o.) and IV: L-glutamine (1000 mg/kg, p.o.). All groups were diabetic except group I. The plasma glucose level, body weight, electrocardiographic abnormalities, hemodynamic changes and left ventricular contractile function, biological markers of cardiotoxicity, antioxidant markers were determined after 4 months after STZ with nicotinamide injection. Histopathological changes of heart tissue were carried out by using H and E stain. L-glutamine treatment improved the electrocardiographic, hemodynamic changes; LV contractile function; biological markers; oxidative stress parameters and histological changes in STZ induced diabetic rats. Results from the present investigation demonstrated that L-glutamine has seemed a cardioprotective activity. PMID:24651718

  2. Antihyperglycemic Effect of Methanol Extract of Syzygium polyanthum (Wight.) Leaf in Streptozotocin-Induced Diabetic Rats.

    PubMed

    Widyawati, Tri; Yusoff, Nor Adlin; Asmawi, Mohd Zaini; Ahmad, Mariam

    2015-09-01

    Syzygium polyanthum (S. polyanthum), a plant belonging to Myrtaceae, is widely used in Indonesian and Malaysian cuisines. Diabetic patients in Indonesia also commonly use it as a traditional medicine. Hence, this study was conducted to investigate the antihyperglycemic effect of the methanol extract (ME) of S. polyanthum leaf and its possible mechanisms of action. To test for hypoglycemic activity, ME was administered orally to normal male Sprague Dawley rats after a 12-h fast. To further test for antihyperglycemic activity, the same treatment was administered to glucose-loaded (intraperitoneal glucose tolerance test, IPGTT) and streptozotocin (STZ)-induced diabetic rats, respectively. Hypoglycemic test in normal rats did not show significant reduction in blood glucose levels (BGLs) by the extract. Furthermore, IPGTT conducted on glucose-loaded normal rats also did not show significant reduction of BGLs. However, repeated administration of metformin and three doses of ME (250, 500 and 1000 mg/kg) for six days caused significant reduction of fasting BGLs in STZ-induced diabetic rats. The possible mechanisms of action of S. polyanthum antihyperglycemic activity were assessed by measurement of intestinal glucose absorption and glucose uptake by isolated rat abdominal muscle. It was found that the extract not only inhibited glucose absorption from the intestine but also significantly increased glucose uptake in muscle tissue. A preliminary phytochemical qualitative analysis of ME indicated the presence of tannins, glycosides, flavonoids, alkaloids and saponins. Additionally, Gas Chromatography-Mass Spectrometry (GC-MS) analysis detected squalene. In conclusion, S. polyanthum methanol leaf extract exerts its antihyperglycemic effect possibly by inhibiting glucose absorption from the intestine and promoting glucose uptake by the muscles. PMID:26389944

  3. Effects of streptozotocin-induced type 1 diabetes mellitus on total protein concentrations and cation contents in the isolated pancreas, parotid, submandibular, and lacrimal glands of rats.

    PubMed

    Changrani, Navin R; Chonkar, Apurva; Adeghate, Ernest; Singh, Jaipaul

    2006-11-01

    This study investigated the effect of streptozotocin (STZ)-induced type 1 diabetes mellitus (DM) on total protein concentration and levels of sodium (Na+), potassium (K+), magnesium (Mg2+), zinc (Zn2+), copper (Cu2+), calcium (Ca2+), and iron (Fe2+) in the pancreas, parotid, submandibular, and lacrimal glands of the rat, compared to age-matched control animals. Protein concentrations were measured by the Bradford Assay, whereas levels of Na+, K+, Mg2+, Zn2+, Cu2+, Ca2+, and Fe2+ were measured by flame photometry and atomic absorbance spectrophotometry. The results show marked changes in the characteristics of diabetic and control animals. Diabetic rats and their different glands weighed significantly (P < 0.05) less compared to age-matched controls. Diabetic rats also have significantly elevated blood glucose and significantly reduced plasma insulin, compared to controls. The results also show that the concentrations of proteins and levels of cations were significantly (P < 0.05) reduced in the pancreas, parotid, submandibular and lacrimal glands of diabetic rats, compared to glands from age-matched animals. These differences in the cation contents and protein levels in STZ-induced DM in this study, along with supporting evidences from previous studies, may provide evidence for the development of long-term complications of DM including exocrine gland deficiencies. PMID:17151325

  4. Ileal apical Na+-dependent bile acid transporter ASBT is upregulated in rats with diabetes mellitus induced by low doses of streptozotocin

    PubMed Central

    Annaba, Fadi; Ma, Ke; Kumar, Pradeep; Dudeja, Amish K.; Kineman, Rhonda D.; Shneider, Benjamin L.; Saksena, Seema; Gill, Ravinder K.

    2010-01-01

    Increased intestinal bile acid absorption and expansion of the bile acid pool has been implicated in the hypercholesterolemia associated with diabetes mellitus. However, the molecular basis of the increase in bile acid absorption in diabetes mellitus is not fully understood. The ileal apical Na+-dependent bile acid transporter (ASBT) is primarily responsible for active reabsorption of the majority of bile acids. Current studies were designed to investigate the modulation of ASBT function and expression in streptozotocin (STZ)-induced diabetes mellitus in rats and to examine the effect of insulin on rat ASBT promoter by insulin. Diabetes mellitus was induced in Sprague-Dawley rats by intraperitoneal injection of low doses of STZ (20 mg/kg body wt) on five consecutive days. Human insulin (10 U/day) was given to a group of diabetic rats for 3 days before euthanasia. RNA and protein were extracted from mucosa isolated from the small intestine and ASBT expression was assessed by real-time quantitative RT-PCR and Western blotting. Our data showed that ASBT mRNA and protein expression were significantly elevated in diabetic rats. Insulin treatment of diabetic rats reversed the increase in ASBT protein expression to control levels. Consistently, ileal Na+-dependent [3H]taurocholic uptake in isolated intestinal epithelial cells was significantly increased in diabetic rats. In vitro studies utilizing intestinal epithelial Caco-2 cells demonstrated that ASBT expression and promoter activity were significantly decreased by insulin. These studies demonstrated that insulin directly influences ASBT expression and promoter activity and that ASBT function and expression are increased in rats with STZ-induced diabetes mellitus. The increase in ASBT expression may contribute to disturbances in cholesterol homeostasis associated with diabetes mellitus. PMID:20651004

  5. Beneficial effect of S-allylcysteine (SAC) on blood glucose and pancreatic antioxidant system in streptozotocin diabetic rats.

    PubMed

    Saravanan, Ganapathy; Ponmurugan, Ponnusamy

    2010-12-01

    The aim of the present study was to evaluate the possible protective effects of S-allyl cysteine (SAC) on the antioxidant defense system of pancreas in streptozotocin(STZ) induced diabetes in rats. The levels of blood glucose and TBARS in plasma and pancreas were estimated in control and experimental groups of rats. To assess the changes in the cellular antioxidant defense system, the level of reduced glutathione in plasma and pancreas and activities of superoxide dismutase and catalase were assayed in pancreatic tissue homogenate. The levels of glucose, TBARS and enzymatic antioxidants were altered in diabetic rats. These alterations were reverted back to near control levels after the treatment of SAC. The antidiabetic and antioxidant effect of SAC was compared with glyclazide, a well-known hypoglycemic drug. These findings suggest that SAC treatment exerts a therapeutic protective nature in diabetes by decreasing oxidative stress. PMID:20839055

  6. Curcumin restores diabetes induced neurochemical changes in the brain stem of Wistar rats.

    PubMed

    Kumar, Peeyush T; George, Naijil; Antony, Sherin; Paulose, Cheramadathikudiyil Skaria

    2013-02-28

    Diabetes mellitus, when poorly controlled, leads to debilitating central nervous system (CNS) complications including cognitive deficits, somatosensory and motor dysfunction. The present study investigated curcumin's potential in modulating diabetes induced neurochemical changes in brainstem. Expression analysis of cholinergic, insulin receptor and GLUT-3 in the brainstem of streptozotocin (STZ) induced diabetic rats were studied. Radioreceptor binding assays, gene expression studies and immunohistochemical analysis were done in the brainstem of male Wistar rats. Our result showed that Bmax of total muscarinic and muscarinic M3 receptors were increased and muscarinic M1 receptor was decreased in diabetic rats compared to control. mRNA level of muscarinic M3, ?7-nicotinic acetylcholine, insulin receptors, acetylcholine esterase, choline acetyltransferase and GLUT-3 significantly increased and M1 receptor decreased in the brainstem of diabetic rats. Curcumin and insulin treatment restored the alterations and maintained all parameters to near control. The results show that diabetes is associated with significant reduction in brainstem function coupled with altered cholinergic, insulin receptor and GLUT-3 gene expression. The present study indicates beneficial effect of curcumin in diabetic rats by regulating the cholinergic, insulin receptor and GLUT-3 in the brainstem similar to the responses obtained with insulin therapy. PMID:23380686

  7. Zinc content in selected tissues in streptozotocin-diabetic rats after maximal exercise.

    PubMed

    Cordova, A

    1994-09-01

    The Zn metabolism in experimental diabetic rats after maximal exercise was investigated. Forty male wistar rats were used, weighing 240 +/- 10 g at the beginning of this experiment. The animals were assigned to one of four experimental groups (n = 10): control at rest (CR), control plus exercise (CE), diabetic at rest (DR), and diabetic plus exercise (DE). Experimental diabetes was produced by a single intraperitoneal injection of streptozotocin (STZ) (60 mg/kg). Thirty days after injection of streptozotocin, the animals of groups CE and DE were forced to acute exercise (swimming) until exhaustion. Glucose, rectal temperature (RT), pH, swimming time (ST), hematocrit (Hct), serum, and tissue (heart, liver, kidney, and muscle) Zn concentrations were measured. The streptozotocin treated animals used in the current experiment were diabetic. Increases in hepatic, renal, muscle, and serum levels Zn at rest and after exercise until exhaustion were found in normal and diabetic rats. ST decreased (-180%) in the diabetic rat group. In conclusion, the results of the present study indicate that STZ-induced diabetes was associated with altered tissue Zn concentration, both at rest and after exercise. PMID:7826814

  8. Effects of Syzygium aromaticum-Derived Triterpenes on Postprandial Blood Glucose in Streptozotocin-Induced Diabetic Rats Following Carbohydrate Challenge

    PubMed Central

    Khathi, Andile; Serumula, Metse R.; Myburg, Rene B.; Van Heerden, Fanie R.; Musabayane, Cephas T.

    2013-01-01

    Purpose Recent reports suggest that the hypoglycaemic effects of the triterpenes involve inhibition of glucose transport in the small intestine. Therefore, the effects of Syzygium spp-derived triterpenes oleanolic acid (OA) and maslinic acid (MA) were evaluated on carbohydrate hydrolyzing enzymes in STZ-induced diabetic rats and consequences on postprandial hyperglycaemia after carbohydrate loading. Methods We determined using Western blot analysis the expressions of ?-amylase and ?-glucosidase and glucose transporters SGLT1 and GLUT2 in the small intestine intestines isolated from diabetic rats treated with OA/MA for 5 weeks. In vitro assays were used to assess the inhibitory activities of OA and MA against ?-amylase, ?-glucosidase and sucrase. Results OA and MA ameliorated postprandial hyperglycemia in carbohydrate loaded diabetic rats as indicated by the significantly small glucose area under the curve (AUC) in treated diabetic animals compared with that in untreated diabetic rats. Western blotting showed that OA and MA treatment not only down-regulated the increase of SGLT1 and GLUT2 expressions in the small intestine of STZ-induced diabetic rats, but also inhibited small intestine ?-amylase, sucrase and ?-glucosidase activity. IC50 values of OA against ?-amylase (3.60 0.18 mmol/L), ?-glucosidase (12.40 0.11 mmol/L) and sucrase (11.50 0.13 mmol/L) did not significantly differ from those of OA and acarbose. Conclusions The results of suggest that OA and MA may be used as potential supplements for treating postprandial hyperglycemia. Novelty of the Work The present observations indicate that besides improving glucose homeostasis in diabetes, OA and MA suppress postprandial hyperglycaemia mediated in part via inhibition of carbohydrate hydrolysis and reduction of glucose transporters in the gastrointestinal tract. Inhibition of ?-glucosidase and ?-amylase can significantly decrease the postprandial hyperglycaemia after a mixed carbohydrate diet and therefore can be an important strategy in the management of postprandial blood glucose levels in NIDDM patients. PMID:24278452

  9. Effect of new and known 1,4-dihydropyridine derivatives on blood glucose levels in normal and streptozotocin-induced diabetic rats.

    PubMed

    Briede, Jan?na; Stivri?a, M?ra; Stoldere, Dzintra; Bisenieks, Eg?ls; Uldri?is, J?nis; Poik?ns, J?nis; Makarova, Nat?lija; Duburs, Gun?rs

    2004-01-01

    Analysis of the effect of several 1,4-DHP Ca(2+) channel antagonists on experimental and clinical diabetes shows that structurally similar Ca(2+) channel antagonists can exert opposite effects on Ca(2+) influx, glucose homeostasis and insulin secretion. The influence of the Ca(2+) channel antagonists on pancreatic beta cell functions is dependent on lipophilicity, interactions with the cell membrane lipid bilayer, with SNAREs protein complexes in cell and vesicle membranes, with intracellular receptors, bioavailability and time of elimination from several organs and the bloodstream. In the present work we studied the effect at several doses of new compounds synthesized in the Latvian Institute of Organic Synthesis on blood glucose levels in normal and STZ-induced diabetic rats. The compounds tested were: 1,4-DHP derivatives cerebrocrast (1), etaftoron (2), OSI-1190 (3), OSI-3802 (4), OSI-2954 (5) and known 1,4-DHP derivatives: niludipine (6), nimodipine (7) and nicardipine (8) which possess different lipophilicities. Analysis of the structure-function relationships of the effect of 1,4-DHP derivatives on glucose metabolism showed that cerebrocrast could evoke qualitative differences in activity. Insertion of an OCHF(2) group in position 2 of the 4-phenylsubstituent and propoxyethylgroup R in ester moieties in positions 3 and 5 of the DHP structure, as well as an increase in the number of carbon atoms in the ester moiety, significantly modified the properties of the compound. Thereby cerebrocrast acquired high lipophilicity and membranotropic properties. Cerebrocrast, in a single administration at low doses (0.05 and 0.5 mg x kg(-1), p.o.), significantly decreased the plasma level of glucose in normal rats and in STZ-induced diabetic rats returned plasma glucose to basal levels. This effect was characterized by a slow onset and a powerful long-lasting influence on glucose metabolism, especially in STZ-induced diabetic rats. PMID:15248181

  10. Postnatal treadmill exercise alleviates short-term memory impairment by enhancing cell proliferation and suppressing apoptosis in the hippocampus of rat pups born to diabetic rats

    PubMed Central

    Kim, Young Hoon; Sung, Yun-Hee; Lee, Hee-Hyuk; Ko, Il-Gyu; Kim, Sung-Eun; Shin, Mal-Soon; Kim, Bo-Kyun

    2014-01-01

    During pregnancy, diabetes mellitus exerts detrimental effects on the development of the fetus, especially the central nervous system. In the current study, we evaluated the effects of postnatal treadmill exercise on short-term memory in relation with cell proliferation and apoptosis in the hippocampus of rat pups born to streptozotocin (STZ)-induced diabetic maternal rats. Adult female rats were mated with male rats for 24 h. Two weeks after mating, the pregnant female rats were divided into two groups: control group and STZ injection group. The pregnant rats in the STZ injection group were administered 40 mg/kg of STZ intraperitoneally. After birth, the rat pups were divided into the following four groups: control group, control with postnatal exercise group, maternal STZ-injection group, and maternal STZ-injection with postnatal exercise group. The rat pups in the postnatal exercise groups were made to run on a treadmill for 30 min once a day, 5 times per week for 2 weeks beginning 4 weeks after birth. The rat pups born to diabetic rats were shown to have short-term memory impairment with suppressed cell proliferation and increased apoptosis in the hippocampal dentate gyrus. Postnatal treadmill exercise alleviated short-term memory impairment by increased cell proliferation and suppressed apoptosis in the rat pups born to diabetic rats. These findings indicate that postnatal treadmill exercise may be used as a valuable strategy to ameliorate neurodevelopmental problems in children born to diabetics. PMID:25210695

  11. Increased cathepsin K and tartrate-resistant acid phosphatase expression in bone of streptozotocin-induced diabetic rats.

    PubMed

    Hie, Mamiko; Shimono, Masumi; Fujii, Kayoko; Tsukamoto, Ikuyo

    2007-12-01

    The effect of insulin-dependent diabetes mellitus (IDDM) on bone metabolism was evaluated using the streptozotocin (STZ)-induced diabetic rat 1 week after the induction of diabetes. The urinary excretion of cross-linked N-telopeptides of type I collagen (NTx) and deoxypyridinoline (Dpd) in diabetic rats increased to 3.6-fold and 1.2-fold the control level, respectively. The amount of hydroxyproline and calcium in the distal femur of diabetic rats significantly decreased to 76% and 90% of the control, respectively. The levels of serum osteocalcin and alkaline phosphatase (ALP) activity in the distal femur of the diabetic rats were significantly reduced to about 40% and 70% of the control levels, respectively. The decrease in the expression osteocalcin was observed in distal femur of the diabetic rats, although the level of ALP mRNA was unchanged. The activity and the mRNA level of tartrate-resistant acid phosphatase (TRAP) increased to 1.5- and 2.3-fold the control level, respectively, in distal femur of the diabetic rats. The activity, protein, and mRNA levels of cathepsin K of diabetic rats also elevated to about 2-, 2.3-, and 2-fold the control levels, respectively. These results suggest that IDDM contributes to bone loss through changes in gene expression of TRAP and cathepsin K in osteoclasts as well as osteocalcin in osteoblasts resulting in increased bone resorptive activity and decreased bone formation. PMID:17916452

  12. Protective effects of enalapril in streptozotocin-induced diabetic rat: studies of DNA damage, apoptosis and expression of CCN2 in the heart, kidney and liver.

    PubMed

    Kushwaha, S; Vikram, A; Jena, G B

    2012-09-01

    Diabetes mellitus is characterized by hyperglycemia, which induces oxidative stress and perturbs a number of pathways, leading to tissue injury. One of the pathological responses to tissue injury is the development of fibrosis and cell death. Enalapril is a non-thiol angiotensin-converting enzyme inhibitor that is commonly used in the treatment of diabetes-associated hypertension. The present study examines the possible beneficial effects of enalapril on the development of diabetes associated fibrosis and DNA damage in rats. Sprague-Dawley rats (250 10 g) were used in the study. Enalapril (10 mg kg(-1) per oral) was administered for four consecutive weeks to the streptozotocin (STZ)-induced diabetic rats. After 4 weeks, all the animals were sacrificed and comet assay (normal and modified) was performed to detect the normal as well as oxidative DNA damage. Expression of profibrotic marker CCN2 and fibrosis was examined in the heart, kidney and liver of diabetic rats. Enalapril treatment significantly restored the malondialdehyde and glutathione content as well as the DNA damage in the heart, kidney and liver of diabetic rat. Significant decrease in the expression of CCN2 was observed in the heart, kidney and liver of diabetic rat receiving enalapril treatment as compared with the diabetic group. Further, the enalapril treatment led to significant decrease in the fibrosis and CCN2 expression in the diabetic group as compared with control. The results of the present study clearly demonstrate that enalapril ameliorates the DNA damage, cell death and expression of CCN2 in the heart, kidney and liver of the STZ-induced diabetic rat. PMID:21416479

  13. Interleukin-6 (IL-6) mediated the increased contraction of distal colon in streptozotocin-induced diabetes in rats via IL-6 receptor pathway

    PubMed Central

    Chang, Xin-Wen; Qin, Ying; Jin, Zhi; Xi, Tao-Fang; Yang, Xiao; Lu, Ze-Hao; Tang, Yu-Ping; Cai, Wen-Ting; Chen, Shao-Jun; Xie, Dong-Ping

    2015-01-01

    Colonic dysmotility occurs in diabetes and blood plasma interleukin (IL)-6 levels are significantly elevated in type 1 diabetes mellitus. The aim of this study was to investigate whether IL-6 and the IL-6 receptor pathway mediates colonic dysfunction in type 1 diabetes mellitus. Male SD rats were treated with a single intraperitoneally injected dose of streptozotocin (STZ), and those displaying sustained high blood glucose were selected as diabetes mellitus models. Longitudinal muscle strips of colon were prepared to monitor colonic contraction in vitro. Contractile responses of strips of colon were recorded following treatment with IL-6 in control animals, and following anti IL-6 antibody treatment in STZ-induced diabetes in rats. Concentration of IL-6 in plasma and colon were determined by ELISA. Expressions of IL-6 ?-receptor and IL-6 ?-receptor in colon tissues were determined by immunohistochemistry or Western blot analysis. The non-diabetes rats treated with IL-6 and the untreated diabetes rats showed increased contraction of distal colon, whereas the diabetes rats treated with anti-IL-6 antibody showed decreased contraction of distal colon compared with the untreated diabetes rats. The IL-6 levels of plasma but not colon increased in diabetes rats. The expression of IL-6 ?-receptor increased in diabetes rats. These results indicate that diabetes rats show an increase in the contractions of distal colon partly via the IL-6-IL-6 receptor pathway. PMID:26191141

  14. Magnetic resonance imaging of the pancreas in streptozotocin-induced diabetic rats: Gadofluorine P and Gd-DOTA

    PubMed Central

    Cho, Hye Rim; Lee, Youkyung; Doble, Philip; Bishop, David; Hare, Dominic; Kim, Young-Jae; Kim, Kwang Gi; Jung, Hye Seung; Park, Kyong Soo; Choi, Seung Hong; Moon, Woo Kyung

    2015-01-01

    AIM: To investigate the performance of Gadofluorine P-enhanced magnetic resonance imaging (MRI) on the diagnosis of diabetes in a streptozotocin (STZ) -induced diabetic rat model. METHODS: Fischer 344 rats were treated with STZ. Rats not treated with STZ served as controls. T1-weighted MRI was performed using a 3T scanner before and after the injection of Gd-DOTA or Gadofluorine P (6 diabetic rats, 5 controls). The normalized signal intensity (SI) and the enhancement ratio (ER) of the pancreas were measured at each time point, and the values were compared between the normal and diabetic rats using the Mann-Whitney test. In addition, the values were correlated with the mean islet number. Optimal cut-off values were calculated using a positive test based on receiver operating characteristics. Intrapancreatic Gd concentration after the injection of each contrast media was measured using laser ablation-inductively coupled plasma-mass spectrometry in a separate set of rats (4 diabetic rats, 4 controls for Gadofluorine P; 2, 2 for Gd-DOTA). RESULTS: The normalized SI and ER of the pancreas using Gd-DOTA were not significantly different between diabetic rats and controls. With Gadofluorine P, the values were significantly higher in the diabetic rats than in the control rats 30 min after injection (P < 0.05). The area under the receiver operating characteristic curve that differentiated diabetic rats from the control group was greater for Gadofluorine P than for Gd-DOTA (0.967 vs 0.667, P = 0.085). An increase in normalized SI 30 min after Gadofluorine P was correlated with a decrease in the mean number of islets (r2 = 0.510, P = 0.014). Intra-pancreatic Gd was higher in rats with Gadofluorine P injection than Gd-DOTA injection (Gadofluorine P vs Gd-DOTA, 7.37 vs 0.00, P < 0.01). A significant difference in the concentration of intrapancreatic Gd was observed between the control and diabetic animals that were sacrificed 30 min after Gadofluorine P injection (control vs diabetic, 3.25 ng/g vs 10.55 ng/g, P < 0.05) CONCLUSION: In this STZ-induced diabetes rat model, Gadofluorine P-enhanced MRI of the pancreas showed high accuracy in the diagnosis of diabetes. PMID:26019447

  15. Sex differences in mesenteric endothelial function of streptozotocin-induced diabetic rats: a shift in the relative importance of EDRFs

    PubMed Central

    Zhang, Rui; Thor, Der; Han, Xiaoyuan; Anderson, Leigh

    2012-01-01

    Several studies suggest that diabetes affects male and female vascular beds differently. However, the mechanisms underlying the interaction of sex and diabetes remain to be investigated. This study investigates whether there are 1) sex differences in the development of abnormal vascular responses and 2) changes in the relative contributions of endothelium-derived relaxing factors in modulating vascular reactivity of mesenteric arteries taken from streptozotocin (STZ)-induced diabetic rats at early and intermediate stages of the disease (1 and 8 wk, respectively). We also investigated the mesenteric expression of the mRNAs for endothelial nitric oxide (NO) synthase (eNOS) and NADPH oxidase (Nox) in STZ-induced diabetes in both sexes. Vascular responses to acetylcholine (ACh) in mesenteric arterial rings precontracted with phenylephrine were measured before and after pretreatment with indomethacin (cyclooxygenase inhibitor), N?-nitro-l-arginine methyl ester (NOS inhibitor), or barium chloride (Kir blocker) plus ouabain (Na+-K+-ATPase inhibitor). We demonstrated that ACh-induced relaxations were significantly impaired in mesenteric arteries from both male and female diabetic rats at 1 and 8 wk. However, at 8 wk the extent of impairment was significantly greater in diabetic females than diabetic males. Our data also showed that in females, the levels of eNOS, Nox2, and Nox4 mRNA expression and the relative importance of NO to the regulation of vascular reactivity were substantially enhanced, whereas the importance of endothelium-derived hyperpolarizing factor (EDHF) was significantly reduced at both 1 and 8 wk after the induction of diabetes. This study reveals the predisposition of female rat mesenteric arteries to vascular injury after the induction of diabetes may be due to a shift away from a putative EDHF, initially the major vasodilatory factor, toward a greater reliance on NO. PMID:22982780

  16. Effects of crocin and zinc chloride on blood levels of zinc and metabolic and oxidative parameters in streptozotocin-induced diabetic rats

    PubMed Central

    Asri-Rezaei, Siamak; Tamaddonfard, Esmaeal; Ghasemsoltani-Momtaz, Behnaz; Erfanparast, Amir; Gholamalipour, Sima

    2015-01-01

    Objectives: Crocin is one of constituents of saffron and has antioxidant property. Zinc chloride is one of the common compounds of zinc with antioxidant activity. The present study was aimed to investigate separate and combined treatment effects of crocin and zinc chloride on blood levels of zinc and metabolic and oxidative parameters in diabetic rats. Materials and Methods: Diabetes was induced by intraperitoneal (i.p.) injection of 50 mg/kg of streptozotocin (STZ) and was confirmed by blood glucose levels higher than 250 mg/dL. After confirmation of diabetes, injections (i.p.) of crocin and zinc chloride were performed for six weeks. At the end of the experiment, blood levels of zinc, glucose, insulin, malodialdehyde (MDA), and total antioxidant capacity (TAC) were measured. ? Results: Crocin (25 and 50 mg/kg) and zinc chloride (5 mg/kg) significantly recovered the decreased levels of zinc, insulin, and TAC and improved the increased levels of glucose and MDA in STZ-induced diabetic rats. In a combination treatment performed with an ineffective dose of crocin (12.5 mg/kg) and a low dose of zinc chloride (1.25 mg/kg), improving effects were observed on the above-mentioned biochemical parameters.? Conclusion: The results indicated that separate and combined treatments with crocin and zinc chloride produced improving effects on the blood levels of zinc, glucose, insulin, MDA and TAC in STZ-induced diabetic rats. PMID:26468459

  17. Blocking VEGF/Caveolin-1 signaling contributes to renal protection of fasudil in streptozotocin-induced diabetic rats

    PubMed Central

    Jin, Jing; Peng, Chao; Wu, Su-zhen; Chen, Hong-min; Zhang, Bai-fang

    2015-01-01

    Aim: RhoA/ROCK signaling plays an important role in diabetic nephropathy, and ROCK inhibitor fasudil exerts nephroprotection in experimental diabetic nephropathy. In this study we investigated the molecular mechanisms underlying the protective actions of fasudil in a rat model of diabetic nephropathy. Methods: Streptozotocin (STZ)-induced diabetic rats, to which fasudil or a positive control drug enalapril were orally administered for 8 months. Metabolic parameters and blood pressure were assessed during the treatments. After the rats were euthanized, kidney samples were collected for histological and molecular biological studies. VEGF, VEGFR1, VEGFR2 and fibronectin expression, and Src and caveolin-1 phosphorylation in the kidneys were assessed using RT-PCR, Western blot and immunohistochemistry assays. The association between VEGFR2 and caveolin-1 was analyzed with immunoprecipitation. Results: Chronic administration of fasudil (30 and 100 mgkg?1d?1) or enalapril (10 mg/kg, bid) significantly attenuated the glomerular sclerosis and albuminuria in the diabetic rats. Furthermore, fasudil treatment prevented the upregulation of VEGF, VEGFR1, VEGFR2 and fibronectin, and the increased association between VEGFR2 and caveolin-1 in the renal cortices, and partially blocked Src activation and caveolin-1 phosphorylation on tyrosine 14 in the kidneys, whereas enalapril treatment had no effects on the VEGFR2/Src/caveolin-1 signaling pathway. Conclusion: Fasudil exerts protective actions in STZ-induced diabetic nephropathy by blocking the VEGFR2/Src/caveolin-1 signaling pathway and fibronectin upregulation. Thus, VEGFR2 may be a potential therapeutic target for the treatment of diabetic nephropathy. PMID:25937636

  18. Effect of spent turmeric on kidney glycoconjugates in streptozotocin-induced diabetic rats

    PubMed Central

    2014-01-01

    Background Curcumin known to have number of medicinal use and masked the fiber containing ukonan like active polysaccharide in turmeric and its pharmacological effect will be addressed on diabetic nephropathy particularly the glycoconjugates of extracellular components viz., glycoproteins and glycosaminoglycans - heparan sulfate (HS). Methods Male Wistar rats were maintained on AIN-76 diet containing 10% spent turmeric and were grouped into control and STZ induced diabetes SFC/TFC and SFD/TFD, respectively. Diabetic status was monitored using blood and urine, and at the end, harvested kidneys were used to study the amelioration of glycoprotiens (collagen) and HS by enzymatic digestion, spectrophotometric, hydroxyproline and agarose electrophoretic methods. Results In the present study spent turmeric (10%) fed diabetic rats showed improved glomerular filtration rate (50%), kidney enlargement (60%) and other glycoconjugate metabolism in kidney. Increased collagen content in diabetic group was observed by hydroxyproline estimation (24%) and periodic acid-Schiff’s (PAS) staining. Furthermore, elevated activities of enzymes involved in the synthesis and degradation of glycosaminoglycans (GAGs) were significantly lowered in spent turmeric fed diabetic group. Improvement in total GAGs (43%) and sulfate content (18%) followed by fractionation of GAGs using specific enzymes led to HS (28%) in the spent turmeric fed diabetic group, when compared to starch fed diabetic group and was further confirmed by electrophoresis of GAG. Conclusion These results clearly indicate beneficial role of spent turmeric in controlling glycoconjugates such as glycoproteins and heparan sulfate related kidney complications during diabetes. PMID:26413492

  19. Achillea Millefolium L. Hydro- Alcoholic Extract Protects Pancreatic Cells by Down Regulating IL- 1? and iNOS Gene Expression in Diabetic Rats

    PubMed Central

    Zolghadri, Yalda; Fazeli, Mehdi; Kooshki, Marzieh; Shomali, Tahoora; Karimaghayee, Negar; Dehghani, Maryam

    2014-01-01

    Interleukin-1? (IL-1?) has a role in ?- cell destruction in autoimmune diabetes by stimulating the expression of inducible nitric oxide synthase (iNOS) that generates the free radical nitric oxide. We aimed to investigate the effect of Achillea millefolium L, as a traditional hypoglycemic agent, on IL-1? and iNOS gene expression of pancreatic tissue in the STZ- induced diabetic rats. Forty adult male Wistar rats were randomly divided into four groups: 1. diabetic control; 2. diabetic rats treated with Achillea millefolium L. extract; 3. normal rats received only extract and 4. negative control (n= 10 each). Diabetes was induced by single i.p. injection of 45 mg/ kg streptozotocin (STZ). Rats in groups 2 and 3 were treated with i.p. injection of Achillea millefolium L. extract (100 mg/ kg/ day) for 14 days. Body weight, serum glucose and insulin levels were assayed at baseline and on days 3, 7, 10 and 14 of the experiment. Finally, the quantity of pancreatic IL-1? and iNOS mRNA was determined by real- time PCR. The mRNA expression level of IL-1? and iNOS genes, was significantly (p<0.001) increased in diabetic rats of group 1. Treatment with Achillea millefolium L. caused a significant (p<0.01) reduction in both IL-1? and iNOS genes expression. Moreover, rats in group 2 had higher insulin level associated with lower glucose level and higher body weight compared to control diabetic group. It seems that beneficial effect of Achillea millefolium L. on STZ- induced diabetes is at least partly due to amelioration of IL-1? and iNOS gene over expression which can have a ?-cell protective effect. PMID:25635252

  20. Berberine ameliorates cold and mechanical allodynia in a rat model of diabetic neuropathy.

    PubMed

    Kim, Si Oh; Kim, Hyun Jee

    2013-06-01

    This study evaluated the antiallodynic properties of berberine on cold and mechanical allodynia after streptozotocin (STZ)-induced diabetes using a rat model. Diabetic neuropathy was induced in rats by intraperitoneal injection of STZ. To measure cold and mechanical allodynia, a 4C plate and von Frey filament were used, respectively. Cold and mechanical allodynia induced by diabetes were significantly decreased by single and repeated intraperitoneal treatment of amitriptyline at 10?mg/kg, and berberine at 10 and 20?mg/kg. The hepatic malondialdehyde, superoxide dismutase, catalase, and glutathione peroxidase activities were significantly increased in diabetic rats as compared with those in intact rats; however, in amitriptyline- and berberine-treated rats, they were significantly decreased as compared to the STZ control. The overall effects of berberine 20?mg/kg on cold and mechanical allodynia were quite similar to those of amitriptyline 10?mg/kg, and berberine exhibited similar antioxidant effects as the same dosage of amitriptyline. In conclusion, berberine (10 and 20?mg/kg) was observed to have antiallodynic effects against diabetes, which are presumed to be associated with antioxidative effects. It can be considered that the anti-inflammatory or antidepressant capacity of berberine could contribute to the antiallonynic effects shown in this study. PMID:23734996

  1. Modulating efficacy of Rebaudioside A, a diterpenoid on antioxidant and circulatory lipids in experimental diabetic rats.

    PubMed

    Saravanan, Ramalingam; Ramachandran, Vinayagam

    2013-09-01

    The present study was to evaluate the protective effects of Rebaudioside A (Reb A) on antioxidant status and lipid profile in streptozotocin (STZ)-induced diabetic rats. Diabetes was induced in Wistar rats by a single intraperitoneal administration of STZ (40mg/kg b.w). Diabetic rats showed significantly increased levels of plasma glucose, thiobarbituric acid reactive substances, hydroperoxides and decreased levels of insulin. The activity of enzymatic antioxidants (superoxide dismutase, catalase and glutathione peroxidase) and the levels of non enzymatic antioxidants (vitamin C, vitamin E and reduced glutathione) were decreased in diabetic rats. The levels of total cholesterol (TC), triglycerides (TGs), free fatty acids (FFAs), phospholipids (PLs), low density lipoproteins (LDL-cholesterol) and very low-density lipoproteins (VLDL-cholesterol) in the plasma significantly increased, while plasma high-density lipoproteins (HDL-cholesterol) were significantly decreased in diabetic rats. Oral administration of Reb A (200mg/kg b.w) brought back plasma glucose, insulin, lipid peroxidation products, enzymatic, non-enzymatic antioxidants and lipid profile levels to near normal. The results of the present investigation suggests that Reb A, a natural sweetener exhibits antilipid peroxidative, antihyperlipidemic and antioxidant properties. PMID:23792234

  2. Time-Course Effect of Electrical Stimulation on Nerve Regeneration of Diabetic Rats

    PubMed Central

    Lin, Yu-Ching; Kao, Chia-Hong; Chen, Chung-Chia; Ke, Cherng-Jyh; Yao, Chun-Hsu; Chen, Yueh-Sheng

    2015-01-01

    Background Electrical stimulation (ES) has been shown to promote nerve regeneration in rats with experimental diabetes induced using streptozotocin (STZ). However, the time-course effect of ES on nerve regeneration of diabetic animals has not been reported in previous studies. The present study attempted to examine the effect of different timing of ES after peripheral nerve transection in diabetic rats. Methodology/Findings Fifty Sprague-Dawley rats were used in the study. They were classified into five groups. STZ-induced diabetes was created in groups A to D. Normal animals in group E were used as the non-diabetic controls. The sciatic nerve was transected and repaired using a silicone rubber conduit across a 10-mm gap in all groups. Groups A to C received ES for 15 minutes every other day for 2 weeks. Stimulation was initiated on day 1 following the nerve repair for group A, day 8 for group B, and day 15 for group C. The diabetic control group D and the normal control group E received no ES. At 30 days after surgery in group A, histological evaluations showed a higher success percentage of regeneration across the 10-mm nerve gap, and the electrophysiological results showed significantly larger mean values of evoked muscle action potential area and amplitude of the reinnervated gastrocnemius muscle compared with group D. Conclusions/Significance It is concluded that an immediate onset of ES may improve the functional recovery of large nerve defect in diabetic animals. PMID:25689049

  3. Mangiferin from Salacia chinensis prevents oxidative stress and protects pancreatic ?-cells in streptozotocin-induced diabetic rats.

    PubMed

    Sellamuthu, Periyar Selvam; Arulselvan, Palanisamy; Muniappan, Balu Periamallipatti; Fakurazi, Sharida; Kandasamy, Murugesan

    2013-08-01

    Oxidative stress in diabetic tissues is a consequence of free radical accumulation with concurrently impaired natural antioxidants status and results in oxidative tissue damage. The present study investigated the protective effects of mangiferin against pancreatic ?-cell damage and on the antioxidant defense systems in streptozotocin (STZ)-induced diabetic rats. Diabetes was experimentally induced by a single intraperitoneal injection of STZ. Oxidative stress biomarkers such as tissue malondialdehyde, hydroperoxides, reduced glutathione (GSH) content, and nonenzymatic antioxidants were measured. Biochemical observations were further substantiated with histological examination and ultrastructural studies in the pancreas of diabetic, glibenclamide and mangiferin-treated diabetic rats (dosage of 40 mg/kg body weight daily for 30 days). Oral administration of mangiferin and glibenclamide to diabetic rats significantly decreased the level of blood glucose and increased levels of insulin. Additionally, mangiferin treatment significantly modulated the pancreatic nonenzymatic antioxidants status (vitamin C, vitamin E, ceruloplasmin, and reduced GSH content) and other oxidative stress biomarkers. The histoarchitecture of diabetic rats showed degenerated pancreas with lower ?-cell counts, but mangiferin treatment effectively regenerated insulin secreting islet cells. The electron microscopic study revealed damaged nuclear envelope and mitochondria and fewer secretory granules in pancreas of diabetic rats; however, mangiferin treatment nearly normalized pancreatic architecture. The present findings suggest that mangiferin treatment exerts a therapeutic protective nature in diabetes by decreasing oxidative stress and protecting against pancreatic ?-cell damage, which may be attributable to its antioxidative properties. PMID:23957355

  4. Chrysin, an anti-inflammatory molecule, abrogates renal dysfunction in type 2 diabetic rats.

    PubMed

    Ahad, Amjid; Ganai, Ajaz Ahmad; Mujeeb, Mohd; Siddiqui, Waseem Ahmad

    2014-08-15

    Diabetic nepropathy (DN) is considered as the leading cause of end-stage renal disease (ESRD) worldwide, but the current available treatments are limited. Recent experimental evidences support the role of chronic microinflammation in the development of DN. Therefore, the tumor necrosis factor-alpha (TNF-α) pathway has emerged as a new therapeutic target for the treatment of DN. We investigated the nephroprotective effects of chrysin (5, 7-dihydroxyflavone) in a high fat diet/streptozotocin (HFD/STZ)-induced type 2 diabetic Wistar albino rat model. Chrysin is a potent anti-inflammatory compound that is abundantly found in plant extracts, honey and bee propolis. The treatment with chrysin for 16weeks post induction of diabetes significantly abrogated renal dysfunction and oxidative stress. Chrysin treatment considerably reduced renal TNF-α expression and inhibited the nuclear transcription factor-kappa B (NF-кB) activation. Furthermore, chrysin treatment improved renal pathology and suppressed transforming growth factor-beta (TGF-β), fibronectin and collagen-IV protein expressions in renal tissues. Chrysin also significantly reduced the serum levels of pro-inflammatory cytokines, interleukin-1beta (IL-1β) and IL-6. Moreover, there were no appreciable differences in fasting blood glucose and serum insulin levels between the chrysin treated groups compared to the HFD/STZ-treated group. Hence, our results suggest that chrysin prevents the development of DN in HFD/STZ-induced type 2 diabetic rats through anti-inflammatory effects in the kidney by specifically targeting the TNF-α pathway. PMID:24848621

  5. Antidiabetic and in vitro antioxidant potential of Hybanthus enneaspermus (Linn) F. Muell in streptozotocin-induced diabetic rats

    PubMed Central

    Patel, DK; Kumar, R; Prasad, SK; Sairam, K; Hemalatha, S

    2011-01-01

    Objective To evaluate antidiabetic and antioxidant potential of Hybanthus enneaspermus in different models. Methods The oral glucose tolerance test (OGTT) and normoglycemic effect of alcoholic extract of Hybanthus enneaspermus (AHE) were evaluated at a dose of 125, 250 and 500 mg/kg p.o. while hypoglycemic activity and effect on body weight were tested at 250 and 500 mg/kg p.o. per day for 21 days in Streptozotocin (STZ) induced diabetic rats. Further, glucose uptake by hemidiaphram was also evaluated. The total polyphenolic and flavonoid were determined and their correlation with various antioxidant assays was also determined. Results The results showed high level of phenolic content in AHE. AHE also exhibited higher total antioxidant capacity, good reducing power and a significant scavenger of reactive oxygen species like DPPH radical, nitric oxide, hydrogen peroxide and deoxyribose. Furthermore there was a significant increase in the body weight and decrease in the blood glucose level on treatment with the AHE. AHE increased glucose uptake on isolated rat hemi-diaphragm compared to control group. Conclusions AHE reduce blood glucose level in STZ-induced diabetic model. It does not show significant effect in normoglycemic study but showes significant effect in OGT. AHE has significant antioxidant activity, which may be attributed to high phenolic content. PMID:23569783

  6. Study on The Effect of Royal Jelly on Reproductive Parameters in Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Ghanbari, Elham; Nejati, Vahid; Najafi, Gholamreza; Khazaei, Mozafar; Babaei, Mohammad

    2015-01-01

    Background Diabetes mellitus has a variety of structural and functional effects on the male reproductive system. Diabetes results in reduced sperm parameters and libido. The present study aims to investigate the effects of royal jelly (RJ) on reproductive parameters of testosterone and malondialdehyde (MDA) production in diabetic rats. Materials and Methods This experimental study was conducted on adult male Wistar rats. The animals were divided into four groups (n=8 per group): control, RJ, diabetic and diabetic treated with RJ. Diabetes was induced by intraperitoneal injection of 60 mg/kg body weight (BW) of streptozotocin (STZ). RJ, at a dose of 100 mg/kg BW was given by gavage. The duration of treatment was six weeks. After the treatment period the rats were sacrificed. The testes were weighed and changes in sperm count, motility, viability, deformity, DNA integrity and chromatin quality were analyzed. Serum testosterone and MDA concentrations of testicular tissue were determined. Data were analyzed by oneway ANOVA with p<0.05 as the significant level. Results STZ-induced diabetes decreased numerous reproductive parameters in rats. Testicular weight, sperm count, motility, viability and serum testosterone levels increased in the diabetic group treated with RJ. There was a significant decrease observed in sperm deformity, DNA integrity, chromatin quality, and tissue MDA levels in diabetic rats treated with RJ compared to the diabetic group (p<0.05). Conclusion RJ improved reproductive parameters such as testicular weight, sperm count, viability, motility, deformity, DNA integrity, chromatin quality, serum testosterone and testicular tissue MDA levels in diabetic rats. PMID:25918599

  7. Investigation of hypoglycemic, hypolipidemic and antioxidant activities of aqueous extract of Terminalia paniculata bark in diabetic rats

    PubMed Central

    Ramachandran, Subramaniam; Rajasekaran, Aiyalu; Manisenthilkumar, KT

    2012-01-01

    Objective To investigate the hypoglycemic, hypolipidemic and antioxidant activities of aqueous extract of Terminalia paniculata bark (AETPB) in streptozotocin (STZ)-induced diabetic rats. Methods Acute toxicity was studied in rats after the oral administration of AETPB to determine the dose to assess hypoglycemic activity. In rats, diabetes was induced by injection of STZ (60 mg/kg, i.p.) and diabetes was confirmed 72 h after induction, and then allowed for 14 days to stabilize blood glucose level. In diabetic rats, AETPB was orally given for 28 days and its effect on blood glucose and body weight was determined on a weekly basis. At the end of the experimental day, fasting blood sample was collected to estimate the haemoglobin (Hb), glycosylated haemoglobin (HbA1c), serum creatinine, urea, serum glutamate-pyruvate transaminase (SGPT), serum glutamate-oxaloacetate transaminase (SGOT) and insulin levels. The liver and kidney were collected to determine antioxidants levels in diabetic rats. Results Oral administration of AETPB did not exhibit toxicity and death at a dose of 2?000 mg/kg. AETPB treated diabetic rats significantly (P<0.001, P<0.01 and P<0.05) reduced elevated blood glucose, HbA1c, creatinine, urea, SGPT and SGOT levels when compared with diabetic control rats. The body weight, Hb, insulin and total protein levels were significantly (P<0.001, P<0.01 and P<0.05) increased in diabetic rats treated with AETPB compared to diabetic control rats. In diabetic rats, AETPB treatment significantly reversed abnormal status of antioxidants and lipid profile levels towards near normal levels compared to diabetic control rats. Conclusions Present study results confirm that AETPB possesses significant hypoglycemic, hypolipidemic and antioxidant activities in diabetic condition. PMID:23569911

  8. Differentiated mesenchymal stem cells ameliorate cardiovascular complications in diabetic rats.

    PubMed

    Haidara, Mohamed A; Assiri, Abdullah S; Youssef, Mary A; Mahmoud, Manal M; Eajaz, Ahmed M S; Al-Hakami, Ahmed; Chandramoorthy, Harish C

    2015-02-01

    Cardiovascular manifestations are one of the major complications of type 1 diabetes mellitus (T1DM) and supersede the slow progression of DM in most cases as the leading cause of mortality. There have been many studies and trials in regenerating the functional ?-cells of islets from mesenchymal stem cells (MSCs) with varied success. The effect of MSCs ex vivo differentiated to mimic functional insulin-secreting ?-cells of islets and their impact on restoration of diabetic complications and transplantation via systemic delivery have not been well studied. In the current study, bone marrow MSCs differentiated to insulin-secreting ?-cells are used to treat STZ-induced diabetic rats. The post-homing effects of the differentiated MSCs (dMSCs) were endogenous with definite reversal of diabetic parameters. Consequently, the altered cardiac functions like heart beat rate, left ventricular performance, contractility index and physiological body weight gain due to hyperglycemia were amelorated into normacy. The primary onset cardiac perfomance and the endothelial activation were well evidenced by high fibrinogen levels and systolic blood pressure (SBP) being reversed on the treatment by dMSCs. Further high basal [Ca(2+)]c in isolated endothelial cells and thereby increased ROS confirmed the endothelial activation. The levels of pro-apoptotic makers p53 and Bax were highly expressed in the diabetic groups indicating oxidative stress through ROS induced by high cytosolic calcium skewing the cells towards apoptosis. The expression of the anti-apoptotic marker Bcl-2 was observed to be low in the diabetic group further augmenting the stress state of endothelial cells (ECs) in T1DM. Restoration of [Ca(2+)]c chelates ROS and the subsequent reversal of pro- and anti-apoptotic markers after the successful treatment of dMSCs proved that endogenous reconstitution of insulin secretion improves diabetic-induced cardiac manifestations. PMID:25413785

  9. Modulatory effects of l-arginine and soy enriched diet on bone homeostasis abnormalities in streptozotocin-induced diabetic rats.

    PubMed

    El-Maraghy, Shohda A; Mehana, Noha Ali

    2015-03-01

    Diabetes mellitus is a complex syndrome which is responsible for numerous complications affecting the whole body. Osteoporosis is regarded as one of the chronic complications of diabetes mellitus that results from reduced bone formation and increased resorption. In this context, we searched for dietary supplements that preserve diabetic bone loss. Parathyroid hormone (PTH) has been suggested as a possible mechanism affecting bone homeostasis in streptozotocin (STZ)-induced diabetic rats. The osteoprotective effects of l-arginine and soy enriched diet were also investigated. Male Wistar rats were allocated into four groups; normal control, untreated STZ-diabetic rats and STZ-diabetic rats treated with either l-arginine (10mg/kg/day) or fed soy enriched diet (200 g/kg diet) for 12 weeks. l-Arginine and soy enriched diet normalized serum PTH level and increased serum osteocalcin level; bone osteocalcin, osteoprotegerin and runt-related transcription factor2 mRNA levels compared to diabetic rats. A decrease in serum pyridinoline, C-terminal telopeptides of type I collagen, cathepsin k levels and bone cathepsin k mRNA level was observed in both treated groups. Both treatments increased serum insulin and insulin like growth factor-1 levels and decreased urinary calcium excretion. In conclusion, l-arginine and soy enriched diet are effective in prevention of osteoporosis associated with diabetes mellitus. PMID:25617479

  10. Extracts of passion fruit peel and seed of Passiflora edulis (Passifloraceae) attenuate oxidative stress in diabetic rats.

    PubMed

    Kandandapani, Salanee; Balaraman, Ashok K; Ahamed, Haja N

    2015-09-01

    This study was aimed at evaluating the anti-diabetic potential of passion fruit Passiflora edulis (EPE) extracts in diabetic rats, following Streptozotocin (STZ) induced oxidative stress. Thirty adult Wistar rats were divided into five groups, with six rats in each group. The control rats were injected intraperitoneally with citrate buffer (pH 4.5). The remaining groups of rats were administered single dose of 45 mgkg(-1) of STZ by intraperitoneal route to induce diabetes. The diabetic animals were treated with 250 and 500 mgkg(-1) of EPE and glibenclamide 0.6 mgkg(-1) for fifteen days by oral route. Blood glucose, end organ oxidative stress marker, and anti-oxidants were assayed. Further, histopathological investigation of pancreas was studied at the end of the experimentation. The results revealed that subacute administration of EPE significantly (P < 0.001) controlled the blood glucose level in the diabetic rats. In addition, EPE extract protected the end organs by restoring the anti-oxidants enzyme, significantly increasing super oxide dismutase level (SOD) and decreasing catalase (CAT) and TBARS level in visceral organs. In conclusion, that EPE extracts showed anti-diabetic and anti-oxidant potential against streptozotocin-induced diabetes. PMID:26412428

  11. Trans-anethole, a terpenoid ameliorates hyperglycemia by regulating key enzymes of carbohydrate metabolism in streptozotocin induced diabetic rats.

    PubMed

    Sheikh, Bashir Ahmad; Pari, Leelavinothan; Rathinam, Ayyasamy; Chandramohan, Ramasamy

    2015-05-01

    Trans-anethole (TA), a terpenoid and a principle constituent of many essential oils from medicinal plants possess hypoglycemic and antioxidant activities. This study was undertaken to explore beneficial effects of TA on key enzymes of carbohydrate metabolism in streptozotocin (STZ)-induced type 2 diabetic rats. Diabetes was induced in male albino Wistar rats by intraperitoneal administration of STZ (40mg/kg BW). TA was administered to diabetic rats at a dose of 20, 40 and 80mg/kg BW for 45 days. However, the dose at 80mg/kg BW, resulted in a significant reduction in the levels of plasma glucose, glycosylated haemoglobin (HbA1c) and increase in the levels of insulin and haemoglobin (Hb). Upon administration of TA, the altered levels of liver glycolytic enzyme (hexokinase), hepatic shunt enzyme (glucose-6-phosphate dehydrogenase) and gluconeogenic enzymes (glucose-6-phosphatase and fructose-1,6-bisphosphatase) in the liver and kidney of diabetic rats significantly reverted to near normal levels. In addition to this, TA also improved the hepatic and muscle glycogen content in diabetic rats. The histological studies showed the ameliorative effect of TA on the ?-cells of pancreas in diabetic rats. The results were compared with glibenclamide, a standard oral hypoglycemic drug. These encouraging findings suggest that TA may be used as a propitious bioactive compound in the development of therapeutic agents against type 2 diabetes mellitus. PMID:25708856

  12. Diabetes changes the levels of ionotropic glutamate receptors in the rat retina

    PubMed Central

    Santiago, Ana R.; Gaspar, Joana M.; Baptista, Filipa I.; Cristvo, Armando J.; Santos, Paulo F.; Kamphuis, Willem

    2009-01-01

    Purpose Diabetic retinopathy (DR) is a leading cause of vision loss and blindness among adults between the age 20 to 74. Changes in ionotropic glutamate receptor subunit composition can affect retinal glutamatergic neurotransmission and, therefore, contribute to visual impairment. The purpose of this study was to investigate whether diabetes leads to changes in ionotropic glutamate receptor subunit expression at the protein and mRNA level in the rat retina. Methods Changes in the expression of ionotropic glutamate receptor subunits were investigated at the mRNA and protein levels in retinas of streptozotocin (STZ)-induced diabetic and age-matched control rats. Animals were euthanized one, four and 12 weeks after the onset of diabetes. Retinal protein extracts were prepared, and the receptor subunit levels were assessed by western blotting. Transcript levels were assessed by real-time quantitative PCR. Results Transcript levels of most ionotropic glutamate receptor subunits were not significantly changed in the retinas of diabetic rats, as compared to age-matched controls but protein levels of ?-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA), kainate, and N-methyl-D-aspartic acid receptors (NMDA) receptors were found to be altered. Conclusions The results provide evidence that diabetes affects the retinal content of ionotropic glutamate receptor subunits at the protein level. The possible implications of these changes on retinal physiology and visual impairment in DR are discussed. PMID:19693289

  13. Astaxanthin Inhibits Expression of Retinal Oxidative Stress and Inflammatory Mediators in Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Yeh, Po-Ting; Huang, Hsin-Wei; Yang, Chung-May; Yang, Wei-Shiung; Yang, Chang-Hao

    2016-01-01

    Purpose We evaluated whether orally administered astaxanthin (AST) protects against oxidative damage in the ocular tissues of streptozotocin (STZ)-induced diabetic rats. Methods and Results Fifty 6-week-old female Wistar rats were randomly assigned to receive an injection of STZ to induce diabetes (n = 40) or to remain uninduced (n = 10). The diabetic rats were randomly selected into four groups and they were separately administered normal saline, 0.6 mg/kg AST, 3 mg/kg AST, or 0.5 mg/kg lutein daily for eight weeks. Retinal functions of each group were evaluated by electroretinography. The expression of oxidative stress and inflammatory mediators in the ocular tissues was then assessed by immunohistochemistry, western blot analysis, ELISA, RT-PCR, and electrophoretic mobility shift assay (EMSA). Retinal functions were preserved by AST and lutein in different levels. Ocular tissues from AST- and lutein-treated rats had significantly reduced levels of oxidative stress mediators (8-hydroxy-2'-deoxyguanosine, nitrotyrosine, and acrolein) and inflammatory mediators (intercellular adhesion molecule-1, monocyte chemoattractant protein-1, and fractalkine), increased levels of antioxidant enzymes (heme oxygenase-1 and peroxiredoxin), and reduced activity of the transcription factor nuclear factor-kappaB (NF-κB). Conclusion The xanthophyll carotenoids AST and lutein have neuroprotective effects and reduce ocular oxidative stress, and inflammation in the STZ diabetic rat model, which may be mediated by downregulation of NF-κB activity. PMID:26765843

  14. Hypoglycemic activity of a polyphenolic oligomer-rich extract of Cinnamomum parthenoxylon bark in normal and streptozotocin-induced diabetic rats.

    PubMed

    Jia, Q; Liu, X; Wu, X; Wang, R; Hu, X; Li, Y; Huang, C

    2009-08-01

    Cinnamon bark has been reported to be effective in the alleviation of diabetes through its antioxidant and insulin-potentiating activities. The water-soluble polyphenolic oligomers found in cinnamon are thought to be responsible for this biological activity. In this study, the hypoglycemic activity of a polyphenolic oligomer-rich extract from the barks of Cinnamomum parthenoxylon (Jack) Nees was studied in normal, transiently hyperglycemic, and streptozotocin (STZ)-induced diabetic rats. Oral administration of the extract at doses of 100, 200, and 300 mg/kg body wt. caused significant changes in body weight loss and fasting blood glucose levels of normal rats. In STZ-induced diabetic rats, after administration of the extract at doses of 100, 200, and 300 mg/kg body wt. over 14 days, the blood glucose levels were decreased by 11.1%, 22.5%, and 38.7%, respectively, and the plasma insulin levels were significantly increased over pre-treatment levels. In an oral glucose tolerance test, the extract produced a significant decrease in glycemia 90 min after the glucose pulse. These results suggest that Cinnamomum parthenoxylon polyphenolic oligomer-rich extract could be potentially useful for post-prandial hyperglycemia treatment. PMID:19464860

  15. Antihyperglycemic Effect of Methanol Extract of Syzygium polyanthum (Wight.) Leaf in Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Widyawati, Tri; Adlin Yusoff, Nor; Asmawi, Mohd Zaini; Ahmad, Mariam

    2015-01-01

    Syzygium polyanthum (S. polyanthum), a plant belonging to Myrtaceae, is widely used in Indonesian and Malaysian cuisines. Diabetic patients in Indonesia also commonly use it as a traditional medicine. Hence, this study was conducted to investigate the antihyperglycemic effect of the methanol extract (ME) of S. polyanthum leaf and its possible mechanisms of action. To test for hypoglycemic activity, ME was administered orally to normal male Sprague Dawley rats after a 12-h fast. To further test for antihyperglycemic activity, the same treatment was administered to glucose-loaded (intraperitoneal glucose tolerance test, IPGTT) and streptozotocin (STZ)-induced diabetic rats, respectively. Hypoglycemic test in normal rats did not show significant reduction in blood glucose levels (BGLs) by the extract. Furthermore, IPGTT conducted on glucose-loaded normal rats also did not show significant reduction of BGLs. However, repeated administration of metformin and three doses of ME (250, 500 and 1000 mg/kg) for six days caused significant reduction of fasting BGLs in STZ-induced diabetic rats. The possible mechanisms of action of S. polyanthum antihyperglycemic activity were assessed by measurement of intestinal glucose absorption and glucose uptake by isolated rat abdominal muscle. It was found that the extract not only inhibited glucose absorption from the intestine but also significantly increased glucose uptake in muscle tissue. A preliminary phytochemical qualitative analysis of ME indicated the presence of tannins, glycosides, flavonoids, alkaloids and saponins. Additionally, Gas Chromatography-Mass Spectrometry (GC-MS) analysis detected squalene. In conclusion, S. polyanthum methanol leaf extract exerts its antihyperglycemic effect possibly by inhibiting glucose absorption from the intestine and promoting glucose uptake by the muscles. PMID:26389944

  16. Response of thymus lymphocytes to streptozotocin-induced diabetes and exogenous vitamin C administration in rats.

    PubMed

    Ozerkan, Dil?ad; Ozsoy, Nesrin; Cebesoy, Suna

    2014-12-01

    Diabetes causes oxidative stress, which in turn generates excessive free radicals resulting in cellular damage. Vitamin C is an antioxidant that protects tissues and organs from oxidative stress. The thymus is one of the most important lymphoid organs, which regulates T-lymphocyte proliferation and maturation. The aim of this study is to investigate the protective effects of vitamin C on the thymus of streptozotocin (STZ)-induced diabetic rats. The mitotic activity and cell integrity of thymic lymphocytes were explored. Wistar Albino rats were divided into three groups: control (Group 1), STZ-diabetes (Group 2) and vitamin C-treated STZ-diabetics (Group 3). Rats received a single intraperitoneal injection of 45 mg/kg STZ to induce diabetes. Vitamin C (20 mg/kg) was administered intragastrically. Semithin and ultrathin sections were examined under a light or an electron microscope, respectively. Considerable numbers of mitotic lymphocytes were observed in the thymus of control rats. In the diabetic rats, however, numbers of mitotic lymphocytes decreased to ?57% of controls, and cell division abnormalities were observed. Additionally, diabetic rats showed degeneration in the structure of the thymus including trabecular thickening, accumulation of lipid vacuoles, heterochromatic nuclei and loss of mitochondrial cristae. Degradation of medullar and cortical integrity was also detected. In the vitamin C-treated STZ-diabetic group, the structure of the thymus and mitotic activity of the lymphocytes were similar to the control group. These results suggest that vitamin C protects the thymus against injury caused by diabetes and restores thymocyte mitotic activity. PMID:25145646

  17. Beneficial effects of ginger (Zingiber officinale) on carbohydrate metabolism in streptozotocin-induced diabetic rats.

    PubMed

    Abdulrazaq, Nafiu Bidemi; Cho, Maung Maung; Win, Ni Ni; Zaman, Rahela; Rahman, Mohammad Tariqur

    2012-10-01

    Zingiber officinale (ZO), commonly known as ginger, has been traditionally used in the treatment of diabetes mellitus. Several studies have reported the hypoglycaemic properties of ginger in animal models. The present study evaluated the antihyperglycaemic effect of its aqueous extract administered orally (daily) in three different doses (100, 300, 500 mg/kg body weight) for a period of 30 d to streptozotocin (STZ)-induced diabetic rats. A dose-dependent antihyperglycaemic effect revealed a decrease of plasma glucose levels by 38 and 68 % on the 15th and 30th day, respectively, after the rats were given 500 mg/kg. The 500 mg/kg ZO significantly (P<005) decreased kidney weight (% body weight) in ZO-treated diabetic rats v. control rats, although the decrease in liver weight (% body weight) was not statistically significant. Kidney glycogen content increased significantly (P<005) while liver and skeletal muscle glycogen content decreased significantly (P<005) in diabetic controls v. normal controls. ZO (500 mg/kg) also significantly decreased kidney glycogen (P<005) and increased liver and skeletal muscle glycogen in STZ-diabetic rats when compared to diabetic controls. Activities of glucokinase, phosphofructokinase and pyruvate kinase in diabetic controls were decreased by 94, 53 and 61 %, respectively, when compared to normal controls; and ZO significantly increased (P<005) those enzymes' activities in STZ-diabetic rats. Therefore, the present study showed that ginger is a potential phytomedicine for the treatment of diabetes through its effects on the activities of glycolytic enzymes. PMID:22152092

  18. Protective effects of Salvia miltiorrhiza injection against learning and memory impairments in streptozotocin-induced diabetic rats

    PubMed Central

    CAI, HUABO; LIAN, LUYA; WANG, YU; YU, YUANYUAN; LIU, WEI

    2014-01-01

    The aim of this study was to explore the protective effects of Salvia miltiorrhiza injection against learning and memory impairment in streptozotocin (STZ)-induced diabetic rats and the possible mechanism involved. Sprague Dawley male rats (n=30) were randomized into three groups: Diabetes, diabetes treated with S. miltiorrhiza injection and normal control. Diabetes was induced by an intraperitoneal injection of STZ (65 mg/kg). The S. miltiorrhiza injection-treated rats received an intraperitoneal injection of S. miltiorrhiza (5 ml/kg/day) while the rats of the other two groups were administered an intraperitoneal injection of the same volume of 0.9% saline for four weeks. After four weeks of treatment, the escape latency and search strategies in the rats were assessed by the Morris water maze test. The protein levels of mitogen-activated protein kinase phosphatase-1 (MKP-1) were also assessed by immunohistochemistry. Four weeks after the induction of diabetes, the body weight of the diabetic rats was significantly lower and the blood glucose concentration was significantly higher than that of the control rats. S. miltiorrhiza injection was observed to improve the blood glucose and learning ability (P<0.05). Compared with the control group, the expression of MKP-1 was significantly decreased in the hippocampal area of the diabetes group; S. miltiorrhiza injection-treated rats showed an increased expression compared with the diabetic rats, but the expression remained lower than that of the normal control group (P<0.05). In conclusion, S. miltiorrhiza injection can improve the learning and memory decline of diabetic rats. The changes in expression of MKP-1 under hyperglycemia may play a role in the protective effects of S. miltiorrhiza against dementia in diabetic rats. PMID:25187809

  19. Effects of Phenolic Compounds of Fermented Thai Indigenous Plants on Oxidative Stress in Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Chaiyasut, Chaiyavat; Kusirisin, Winthana; Lailerd, Narissara; Lerttrakarnnon, Peerasak; Suttajit, Maitree; Srichairatanakool, Somdet

    2011-01-01

    We investigated the effects of antioxidant activity of fermentation product (FP) of five Thai indigenous products on oxidative stress in Wistar rats with streptozotocin (STZ)-induced diabetes type II. The rats were fed with placebo and with the FP (2 and 6 mL/kg body weight/day) for 6 weeks. Rutin, pyrogallol and gallic acid were main compounds found in the FP. Plasma glucose levels in diabetic rats receiving the higher dose of the FP increased less when compared to the diabetic control group as well as the group receiving the lower FP dose (13.1%, 29%, and 21.1%), respectively. A significant dose-dependent decrease in plasma levels of thiobarbituric acid reactive substance (P < .05) was observed. In addition, the doses of 2 and 6 mL FP/kg/day decreased the levels of erythrocyte ROS in diabetic rats during the experiment, but no difference was observed when compared to the untreated diabetic rat group. Results imply that FP decreased the diabetes-associated oxidative stress to a large extent through the inhibition of lipid peroxidation. The FP also improved the abnormal glucose metabolism slightly but the difference was not statistically significant. Thus, FP may be a potential therapeutic agent by reducing injury caused by oxidative stress associated with diabetes. PMID:21423638

  20. A new Agkistrodon halys venom-purified protein C activator prevents myocardial fibrosis in diabetic rats

    PubMed Central

    Li, Shu; Hong, Yun; Jin, Xin; Zhang, Genbao; Hu, Zaichang; Nie, Liuwang

    2015-01-01

    Aim To assess the effects of protein C activator (PCA) from Agkistrodon halys snake venom on cardiac fibrosis in streptozotocin (STZ) induced diabetic rat model, and investigate the mechanisms of its action. Methods PCA was identified by one-dimensional reversed phase liquid chromatography – mass spectrometry/mass spectrometry. Male Sprague-Dawley rats (120-140 g) were randomly assigned to negative control (NC) and diabetic group. Diabetes was induced by STZ in high-fat diet fed rats. Diabetic group was subdivided into three groups: diabetic group (DM), diabetic group treated with PCA (0.5, 2, and 8 mg/kg), and diabetic group treated with metformin (5 mg/kg, positive control). NC and DM groups received the same volume of distilled water. Left ventricular mass index (LVWI) and collagen volume fraction were measured by hematoxylin and eosin and Masson staining. Transforming growth factor beta-1 (TGF-β1) and interleukin 1 beta (IL-1β) levels were determined by enzyme-linked immunosorbent assay. Results The diabetic rat model was successfully established by STZ induction and high-fat diet. Glucose level, LVWI, TGF-β1 and IL-1β level, and collagen volume fraction were significantly reduced in diabetic rats treated by PCA in a dose-dependent manner (P < 0.050), especially in the high dose (8 mg/kg) group (P < 0.010), compared to diabetes group. The high dose PCA had the same effect as metformin positive control in reducing the level of fasting blood glucose. PCA decreased the expression of MMP-2 and reduced that of TIMP-2. Conclusion Our results indicate that PCA has anti-fibrotic effects and that it may be used to treat myocardial fibrosis. PMID:26526881

  1. Increased GABAergic Output in the Ventromedial Hypothalamus Contributes to Impaired Hypoglycemic Counterregulation in Diabetic Rats

    PubMed Central

    Chan, Owen; Paranjape, Sachin; Czyzyk, Daniel; Horblitt, Adam; Zhu, Wanling; Ding, Yuyan; Fan, Xiaoning; Seashore, Margretta; Sherwin, Robert

    2011-01-01

    OBJECTIVE Impaired glucose counterregulation during hypoglycemia is well documented in patients with type 1 diabetes; however, the molecular mechanisms underlying this defect remain uncertain. We reported that the inhibitory neurotransmitter ?-aminobutyric acid (GABA), in a crucial glucose-sensing region within the brain, the ventromedial hypothalamus (VMH), plays an important role in modulating the magnitude of the glucagon and epinephrine responses to hypoglycemia and investigated whether VMH GABAergic tone is altered in diabetes and therefore might contribute to defective counterregulatory responses. RESEARCH DESIGN AND METHODS We used immunoblots to measure GAD65 protein (a rate-limiting enzyme in GABA synthesis) and microdialysis to measure extracellular GABA levels in the VMH of two diabetic rat models, the diabetic BB rat and the streptozotocin (STZ)-induced diabetic rat, and compared them with nondiabetic controls. RESULTS Both diabetic rat models exhibited an ~50% increase in GAD65 protein as well as a twofold increase in VMH GABA levels compared with controls under baseline conditions. Moreover, during hypoglycemia, VMH GABA levels did not change in the diabetic animals, whereas they significantly declined in nondiabetic animals. As expected, glucagon responses were absent and epinephrine responses were attenuated in diabetic rats compared with their nondiabetic control counterparts. The defective counterregulatory response in STZ-diabetic animals was restored to normal with either local blockade of GABAA receptors or knockdown of GAD65 in the VMH. CONCLUSIONS These data suggest that increased VMH GABAergic inhibition is an important contributor to the absent glucagon response to hypoglycemia and the development of counterregulatory failure in type 1 diabetes. PMID:21411513

  2. Protective Nature of Mangiferin on Oxidative Stress and Antioxidant Status in Tissues of Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Sellamuthu, Periyar Selvam; Arulselvan, Palanisamy; Kamalraj, Subban; Fakurazi, Sharida; Kandasamy, Murugesan

    2013-01-01

    Oxidative stress plays an important role in the progression of diabetes complications. The aim of the present study was to investigate the beneficial effect of oral administration of mangiferin in streptozotocin (STZ)-induced diabetic rats by measuring the oxidative indicators in liver and kidney as well as the ameliorative properties. Administration of mangiferin to diabetic rats significantly decreased blood glucose and increased plasma insulin levels. The activities of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) and level of reduced glutathione (GSH) were significantly (P < 0.05) decreased while increases in the levels of lipidperoxidation (LPO) markers were observed in liver and kidney tissues of diabetic control rats as compared to normal control rats. Oral treatment with mangiferin (40?mg/kg?b.wt/day) for a period of 30 days showed significant ameliorative effects on all the biochemical and oxidative parameters studied. Diabetic rats treated with mangiferin restored almost normal architecture of liver and kidney tissues, which was confirmed by histopathological examination. These results indicated that mangiferin has potential ameliorative effects in addition to its antidiabetic effect in experimentally induced diabetic rats. PMID:24167738

  3. Bixin and Norbixin Have Opposite Effects on Glycemia, Lipidemia, and Oxidative Stress in Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Zanchi, Mariane Magalhes; Bochi, Guilherme Vargas; Somacal, Sabrina

    2014-01-01

    The present study investigated the effects of oral administration of annatto carotenoids (bixin (BIX) and norbixin (NBIX)) on glucose levels, lipid profiles, and oxidative stress parameters in streptozotocin (STZ)-induced diabetic rats. Animals were treated for 30 days in the following groups: nondiabetic control, diabetic vehicle, diabetic 10?mg/kg BIX, diabetic 100?mg/kg BIX, diabetic 10?mg/kg NBIX, diabetic 100?mg/kg NBIX, diabetic metformin, and diabetic insulin. Blood glucose, LDL cholesterol, and triglyceride levels were reduced in the diabetic rats treated with BIX. BIX treatment prevented protein oxidation and nitric oxide production and restored superoxide dismutase activity. NBIX treatment did not change most parameters assessed, and at the highest dose, it increased LDL cholesterol and triglycerides levels and showed prooxidant action (increased protein oxidation and nitric oxide levels). These findings suggested that BIX could have an antihyperglycemic effect, improve lipid profiles, and protect against damage induced by oxidative stress in the diabetic state. Because NBIX is a water-soluble analog of BIX, we propose that lipophilicity is crucial for the protective effect of annatto carotenoids against streptozotocin-induced diabetes. PMID:24624139

  4. AB172. Low-intensity pulsed ultrasound recovers erectile function in streptozotocin-induced type I diabetic rats

    PubMed Central

    Lei, Hongen; Guan, Ruili; Gao, Zhezhu; Yang, Bicheng; Xin, Zhongcheng

    2015-01-01

    Objective To investigate the effect of low-intensity pulsed ultrasound (LIPUS) as a treatment for erectile dysfunction (ED) in a rat model of type I diabetes mellitus (DM) induced by streptozotocin (STZ). Methods Seventy male Sprague-Dawley rats were randomly assigned to two cohorts: a normal control (NC) group and a STZ-induced DM group, which was further sub-divided into DM, DM + LIPUS 100, DM + LIPUS 200 and DM + LIPUS 300 groups and a DM+LESWT (low-energy shock wave therapy) 300 positive control group. Animals in the LIPUS subgroups were treated at different energy levels (100, 200, 300 mW/cm2) for 3 min, and animals in the LESWT group received 300 shocks at 0.09 mJ/mm2. All procedures were repeated 3 times per week for 2 weeks. After a 2-week wash-out period, intracavernous pressure (ICP) was measured; the midpenile region was examined histologically; and VEGF, αSMA, eNOS and nNOS expression, and activity of the TGF-β1/Smad/CTGF signaling pathway were examined in penile tissue by Western blot analysis. Results LIPUS therapy significantly improved erectile function in diabetic rats, as evidenced by enhanced ICP levels, increased endothelial and smooth muscle content, a higher collagen I/collagen III ratio, increased quantity of elastic fibers, and elevated eNOS and nNOS expression. Interestingly, LIPUS was also associated with down-regulation of the TGF-β1/Smad/CTGF signaling pathway in penile tissue, whose activation is correlated with ED pathology. Conclusions LIPUS therapy improved erectile function and reversed pathological changes in penile tissue of STZ-induced diabetic rats. LIPUS therapy has potential as a non-invasive therapy for diabetic ED in the clinic.

  5. Gabapentin reverses microglial activation in the spinal cord of streptozotocin-induced diabetic rats.

    PubMed

    Wodarski, Rachel; Clark, Anna K; Grist, John; Marchand, Fabien; Malcangio, Marzia

    2009-09-01

    Diabetes mellitus is the leading cause of peripheral neuropathy worldwide. Despite this high level of incidence, underlying mechanisms of the development and maintenance of neuropathic pain are still poorly understood. Evidence supports a prominent role of glial cells in neuropathic pain states. Gabapentin is used clinically and shows some efficacy in the treatment of neuropathic pain. Here we investigate the distribution and activation of spinal microglia and astrocytes in streptozotocin (STZ)-diabetic rats and the effect of the gold standard analgesic, Gabapentin, on these cells. Mechanical allodynia was observed in four week-diabetic rats. Oral administration of Gabapentin significantly attenuated mechanical allodynia. Quantification of cell markers Iba-1 for microglia and GFAP for astrocytes revealed extensive activation of microglia in the dorsal horn of diabetic rats, whereas a reduction in the number of astrocytes could be observed. In addition, an attenuation of microglial activation correlated with reduced allodynia following Gabapentin treatment, while Gabapentin had no effect on the number of astrocytes. Here we show a role of microglia in STZ-induced mechanical allodynia and furthermore, that the anti-allodynic effect of Gabapentin may be linked to a reduction of spinal microglial activation. Astrocytic activation in this model appears to be limited and is unaffected by Gabapentin treatment. Consequently, spinal microglial activation is a key mechanism underlying diabetic neuropathy. Furthermore, we suggest that Gabapentin may exert its anti-allodynic actions partially through alterations of microglial cell function. PMID:18977160

  6. Exercise Training Attenuates Upregulation of p47phox and p67phox in Hearts of Diabetic Rats

    PubMed Central

    Sharma, Neeru M.; Rabeler, Brandon; Zheng, Hong; Raichlin, Eugenia; Patel, Kaushik P.

    2016-01-01

    Exercise training (ExT) is currently being used as a nonpharmacological strategy to improve cardiac function in diabetic patients. However, the molecular mechanism(s) underlying its beneficial effects remains poorly understood. Oxidative stress is known to play a key role in the pathogenesis of diabetic cardiomyopathy and one of the enzyme systems that produce reactive oxygen species is NADH/NADPH oxidase. The goal of this study was to investigate the effect of streptozotocin- (STZ-) induced diabetes on expression of p47phox and p67phox, key regulatory subunits of NADPH oxidase, in cardiac tissues and determine whether ExT can attenuate these changes. Four weeks after STZ treatment, expression of p47phox and p67phox increased 2.3-fold and 1.6-fold, respectively, in left ventricles of diabetic rats and these increases were attenuated with three weeks of ExT, initiated 1 week after onset of diabetes. In atrial tissues, there was increased expression of p47phox (74%), which was decreased by ExT in diabetic rats. Furthermore, increased collagen III levels in diabetic hearts (52%) were significantly reduced by ExT. Taken together, ExT attenuates the increased expression of p47phox and p67phox in the hearts of diabetic rats which could be an underlying mechanism for improving intracardiac matrix and thus cardiac function and prevent cardiac remodeling in diabetic cardiomyopathy. PMID:26989452

  7. The Antidiabetic Effect of Low Doses of Moringa oleifera Lam. Seeds on Streptozotocin Induced Diabetes and Diabetic Nephropathy in Male Rats

    PubMed Central

    Al-Malki, Abdulrahman L.; El Rabey, Haddad A.

    2015-01-01

    The antidiabetic activity of two low doses of Moringa seed powder (50 and 100?mg/kg body weight, in the diet) on streptozotocin (STZ) induced diabetes male rats was investigated. Forty rats were divided into four groups. The diabetic positive control (STZ treated) group showed increased lipid peroxide, increased IL-6, and decreased antioxidant enzyme in the serum and kidney tissue homogenate compared with that of the negative control group. Immunoglobulins (IgA, IgG), fasting blood sugar, and glycosylated hemoglobin (HbA1c) were also increased as a result of diabetes in G2 rats. Moreover albumin was decreased, and liver enzymes and ?-amylase were not affected. In addition, the renal functions and potassium and sodium levels in G2 were increased as a sign of diabetic nephropathy. Urine analysis showed also glucosuria and increased potassium, sodium, creatinine, uric acid, and albumin levels. Kidney and pancreas tissues showed also pathological alteration compared to the negative control group. Treating the diabetic rats with 50 or 100?mg Moringa seeds powder/kg body weight in G3 and G4, respectively, ameliorated the levels of all these parameters approaching the negative control values and restored the normal histology of both kidney and pancreas compared with that of the diabetic positive control group. PMID:25629046

  8. The antidiabetic effect of low doses of Moringa oleifera Lam. seeds on streptozotocin induced diabetes and diabetic nephropathy in male rats.

    PubMed

    Al-Malki, Abdulrahman L; El Rabey, Haddad A

    2015-01-01

    The antidiabetic activity of two low doses of Moringa seed powder (50 and 100 mg/kg body weight, in the diet) on streptozotocin (STZ) induced diabetes male rats was investigated. Forty rats were divided into four groups. The diabetic positive control (STZ treated) group showed increased lipid peroxide, increased IL-6, and decreased antioxidant enzyme in the serum and kidney tissue homogenate compared with that of the negative control group. Immunoglobulins (IgA, IgG), fasting blood sugar, and glycosylated hemoglobin (HbA1c) were also increased as a result of diabetes in G2 rats. Moreover albumin was decreased, and liver enzymes and α-amylase were not affected. In addition, the renal functions and potassium and sodium levels in G2 were increased as a sign of diabetic nephropathy. Urine analysis showed also glucosuria and increased potassium, sodium, creatinine, uric acid, and albumin levels. Kidney and pancreas tissues showed also pathological alteration compared to the negative control group. Treating the diabetic rats with 50 or 100 mg Moringa seeds powder/kg body weight in G3 and G4, respectively, ameliorated the levels of all these parameters approaching the negative control values and restored the normal histology of both kidney and pancreas compared with that of the diabetic positive control group. PMID:25629046

  9. Targeting AGEs Signaling Ameliorates Central Nervous System Diabetic Complications in Rats

    PubMed Central

    Zakaria, Mohamed Naguib; El-Bassossy, Hany M.; Barakat, Waleed

    2015-01-01

    Diabetes is a chronic endocrine disorder associated with several complications as hypertension, advanced brain aging, and cognitive decline. Accumulation of advanced glycation end products (AGEs) is an important mechanism that mediates diabetic complications. Upon binding to their receptor (RAGE), AGEs mediate oxidative stress and/or cause cross-linking with proteins in blood vessels and brain tissues. The current investigation was designed to investigate the effect of agents that decrease AGEs signaling, perindopril which increases soluble RAGE (sRAGE) and alagebrium which cleaves AGEs cross-links, compared to the standard antidiabetic drug, gliclazide, on the vascular and central nervous system (CNS) complications in STZ-induced (50?mg/kg, IP) diabetes in rats. Perindopril ameliorated the elevation in blood pressure seen in diabetic animals. In addition, both perindopril and alagebrium significantly inhibited memory decline (performance in the Y-maze), neuronal degeneration (Fluoro-Jade staining), AGEs accumulation in serum and brain, and brain oxidative stress (level of reduced glutathione and activities of catalase and malondialdehyde). These results suggest that blockade of AGEs signaling after diabetes induction in rats is effective in reducing diabetic CNS complications. PMID:26491434

  10. Cardioprotective effects of gallic acid in diabetes-induced myocardial dysfunction in rats

    PubMed Central

    Patel, Snehal S.; Goyal, Ramesh K.

    2011-01-01

    Background: Normalization of hyperglycemia, hyperlipidemia, and oxidative stress is an important objective in preventing diabetes-induced cardiac dysfunction. Objective: This study was undertaken to examine the effects of gallic acid in myocardial dysfunctions associated with type-1 diabetes. Materials and Methods: Diabetes was induced by single intravenous injection of streptozotocin (STZ, 50 mg/kg i.v.). Gallic acid was administered daily at three different doses (100, 50, and 25 mg/kg p.o.) for 8 weeks at the end of which blood samples were collected and analyzed for various biochemical parameters. Results: Injection of STZ produced significant loss of body weight (BW), polyphagia, polydypsia, hyperglycemia, hypoinsulinemia, hyperlipidemia, hypertension, bradycardia, and myocardial functional alterations. Treatment with gallic acid significantly lowered fasting glucose, the AUCglucose level in a dose-dependent manner; however, the insulin level was not increased significantly at same the dose and prevented loss of BW, polyphagia, and polydypsia in diabetic rats. It also prevented STZ-induced hyperlipidemia, hypertension, bradycardia, structural alterations in cardiac tissue such as increase in force of contraction, left ventricular weight to body weight ratio, collagen content, protein content, serum lactate dehydrogenase, and creatinine kinase levels in a dose-dependent manner. Further, treatment also produced reduction in lipid peroxidation and increase in antioxidant parameters in heart of diabetic rats. Conclusion: The results of this study suggest that gallic acid to be beneficial for the treatment of myocardial damage associated with type-1 diabetes. PMID:22224046

  11. Streptozotocin Diabetes Attenuates the Effects of Nondepolarizing Neuromuscular Relaxants on Rat Muscles

    PubMed Central

    Huang, Lina; Chen, Dan

    2014-01-01

    The hypothesis of this study was that diabetes-induced desensitization of rat soleus (SOL) and extensor digitorum longus (EDL) to non-depolarizing muscle relaxants (NDMRs) depends on the stage of diabetes and on the kind of NDMRs. We tested the different magnitude of resistance to vecuronium, cisatracurium, and rocuronium at different stages of streptozotocin (STZ)-induced diabetes by the EDL sciatic nerve-muscle preparations, and the SOL sciatic nerve-muscle preparations from rats after 4 and 16 weeks of STZ treatment. The concentration-twitch tension curves were significantly shifted from those of the control group to the right in the diabetic groups. Concentration giving 50% of maximal inhibition (IC50) was larger in the diabetic groups for all the NDMRs. For rocuronium and cisatracurium in both SOL and EDL, IC50 was significantly larger in diabetic 16 weeks group than those in the diabetic 4 weeks group. For SOL/EDL, the IC50 ratios were significantly largest in the diabetic 16 weeks group, second largest in the diabetic 4 weeks group, and smallest for the control group. Diabetes-induced desensitization to NDMRs depended on the stage of diabetes and on the different kind of muscles observed while was independent on different kind of NDMRs. The resistance to NDMRs was stronger in the later stage of diabetes (16 versus 4 weeks after STZ treatment). Additionally, when monitoring in SOL, diabetes attenuated the actions of neuromuscular blockade more intensely than that in EDL. Nonetheless, the hyposensitivity to NDMRs in diabetes was not relevant for the kind of NDMRs. PMID:25598659

  12. Region-specific cerebral metabolic alterations in streptozotocin-induced type 1 diabetic rats: an in vivo proton magnetic resonance spectroscopy study.

    PubMed

    Zhang, Hui; Huang, Mingming; Gao, Lifeng; Lei, Hao

    2015-11-01

    Clinical and experimental in vivo (1)H-magnetic resonance spectroscopy ((1)H-MRS) studies have demonstrated that type 1 diabetes mellitus (T1DM) is associated with cerebral metabolic abnormalities. However, less is known whether T1DM induces different metabolic disturbances in different brain regions. In this study, in vivo (1)H-MRS was used to measure metabolic alterations in the visual cortex, striatum, and hippocampus of streptozotocin (STZ)-induced uncontrolled T1DM rats at 4 days and 4 weeks after induction. It was observed that altered neuronal metabolism occurred in STZ-treated rats as early as 4 days after induction. At 4 weeks, T1DM-related metabolic disturbances were clearly region specific. The diabetic visual cortex had more or less normal-appearing metabolic profile; while the striatum and hippocampus showed similar abnormalities in neuronal metabolism involving N-acetyl aspartate and glutamate; but only the hippocampus exhibited significant changes in glial markers such as taurine and myo-inositol. It is concluded that cerebral metabolic perturbations in STZ-induced T1DM rats are region specific at 4 weeks after induction, perhaps as a manifestation of varied vulnerability among the brain regions to sustained hyperglycemia. PMID:26036938

  13. Rhinacanthus nasutus Improves the Levels of Liver Carbohydrate, Protein, Glycogen, and Liver Markers in Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Visweswara Rao, Pasupuleti; Madhavi, K.; Dhananjaya Naidu, M.; Gan, Siew Hua

    2013-01-01

    The present study was designed to investigate the total carbohydrate, total protein, and glycogen levels in the liver and to measure functional liver markers such as aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in streptozotocin-(STZ-) induced diabetic rats after treatment with methanolic extract of Rhinacanthus nasutus (R. nasutus). The methanolic extract of R. nasutus was orally administered at 200 mg/kg/day while glibenclamide was administered at 50 mg/kg/day. All animals were treated for 30 days before being sacrificed. The amounts of carbohydrate, glycogen, proteins, and liver markers (AST and ALT) were measured in the liver tissue of the experimental animals. The levels of carbohydrate, glycogen, and proteins were significantly reduced in the diabetic rats but were augmented considerably after 30 days of R. nasutus treatment. The elevated AST and ALT levels in diabetic rats showed a significant decline after treatment with R. nasutus for 30 days. These results show that the administration of R. nasutus ameliorates the altered levels of carbohydrate, glycogen, proteins, and AST and ALT observed in diabetic rats and indicate that R. nasutus restores overall metabolism and liver function in experimental diabetic rats. In conclusion, the outcomes of the present study support the traditional belief that R. nasutus could ameliorate the diabetic state. PMID:24204387

  14. Antihyperlipidemic Activity of the Ethyl-acetate Fraction of Stereospermum Suaveolens in Streptozotocin-induced Diabetic Rats

    PubMed Central

    Thirumalaisamy, Balasubramanian; Prabhakaran, Senthilkumar Gnanavadevel; Marimuthu, Karthikeyan; Chatterjee, Tapan Kumar

    2013-01-01

    Objectives: Dyslipidemia in diabetes mellitus is a significant risk factor for the development of cardiovascular complications. The aim of this study was to evaluate the effect of the ethyl-acetate fraction of an ethanolic extract from Streospermum suaveolens on lipid metabolism in streptozotocin (STZ)-induced diabetic rats. Methods: Diabetes was induced by intraperitonial injection of STZ (50 mg/kg). Diabetic rats were treated with an ethyl-acetate fraction orally at doses of 200 and 400 mg/kg daily for 14 days. On the 15th day, serum lipid profiles, such as total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL), were estimated in experimental rats. The atherogenic (AI) and the coronary risk (CRI) indices were also evaluated. Results: The ethyl-acetate fraction at doses of 200 and 400 mg/kg significantly (P< 0.001) and dose-dependently reduced serum cholesterol, triglycerides and LDL, but increased HDL towards near normal levels as compared to diabetic control rats. The fraction also significantly (P< 0.001) lowered the atherogenic index (AI) and coronary risk index (CAI) in a dose-dependent manner. Conclusion: The present study demonstrated that the ethyl-acetate fraction of Stereospermum suaveolens exhibits a potent antihyperlipidemic activity in hyperglycemic rats and suggests that the plant may have therapeutic value in treating the diabetic complication of hyperlipidemia. PMID:25780672

  15. Anti-diabetic effects of ethanol extract of Bryonia laciniosa seeds and its saponins rich fraction in neonatally streptozotocin-induced diabetic rats

    PubMed Central

    Patel, Sandip B.; Santani, Devdas; Patel, Veena; Shah, Mamta

    2015-01-01

    Context: Bryonia laciniosa Linn. (Cucurbitaceae) seed is used in traditional medicine for a number of ailments including metabolic disorders. Aim: This study evaluated the anti-diabetic action of the ethanol extract of B. laciniosa seeds and saponin fraction of it through its effect on hyperglycemia, dyslipidaemia and oxidative stress in neonatally streptozotocin (n-STZ)-induced diabetic rats (n-STZ diabetic rats). Materials and Methods: Ethanol extract (250 and 500 mg/kg; p.o.), saponin fraction (100 and 200 mg/kg; p.o.) and standard drug glibenclamide (3 mg/kg; p.o.) were administered to diabetic rats when the rats were 6 weeks old and continued for 10 consecutive weeks. Effects of ethanol extract and saponin fraction on various biochemical parameters were studied in diabetic rats. Results: The treatment with ethanol extract and saponin fraction for 10 weeks decrease in the levels of glucose, triglycerides, cholesterol, high-density lipoprotein, low-density lipoprotein, very low-density lipoprotein, serum urea, serum creatinine and diminished activities of aspartate transaminase, and alanine transaminase. The anti-hyperglycemic nature of B. laciniosa is probably brought about by the extra- the pancreatic mechanism as evidenced from unchanged levels of plasma insulin. B. laciniosa modulated effect of diabetes on the liver malondialdehyde, reduced glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) activity. Administration of ethanol extract and saponin fraction to diabetic rats showed a significant reversal of disturbed antioxidant status. Significant increase in SOD, CAT, and levels of GSH was observed in treated n-STZ diabetic rats. Conclusion: The present study reveals the efficacy of B. laciniosa seed extract and its saponin fraction in the amelioration of n-STZ diabetic rats. PMID:25598641

  16. Insulin treatment normalizes retinal neuroinflammation but not markers of synapse loss in diabetic rats

    PubMed Central

    Masser, Dustin R.; VanGuilder Starkey, Heather D.; Bixler, Georgina V.; Dunton, Wendy; Bronson, Sarah K.; Freeman, Willard M.

    2014-01-01

    Diabetic retinopathy is one of the leading causes of blindness in developed countries, and a majority of patients with type I and type II diabetes will develop some degree of vision loss despite blood glucose control regimens. The effects of different insulin therapy regimens on early metabolic, inflammatory and neuronal retinal disease processes such as retinal neuroinflammation and synapse loss have not been extensively investigated. This study compared 3 months non-diabetic and streptozotocin (STZ)-induced diabetic Sprague Dawley rats. Diabetic rats received either no insulin treatment, systemic insulin treatment beginning after 1 week uncontrolled diabetes (early intervention, 11 weeks on insulin), or after 1.5 months uncontrolled diabetes (late intervention, 6 weeks on insulin). Changes in both whole animal metabolic and retinal inflammatory markers were prevented by early initiation of insulin treatment. These metabolic and inflammatory changes were also normalized by the later insulin intervention. Insulin treatment begun 1 week after diabetes induction ameliorated loss of retinal synapse markers. Synapse markers and presumably synapse numbers were equivalent in uncontrolled diabetes and when insulin treatment began at 1.5 months of diabetes. These findings are in agreement with previous demonstrations that retinal synapses are lost within 1 month of uncontrolled diabetes and suggest that synapses are not regained with glycemic control and restoration of insulin signaling. However, increased expression of metabolic and inflammatory markers associated with diabetes was reversed in both groups of insulin treatment. This study also emphasizes the need for insulin treatment groups in diabetic retinopathy studies to provide a more faithful modeling of the human condition. PMID:24931083

  17. Amelioration of pancreatic and renal derangements in streptozotocin-induced diabetic rats by polyphenol extracts of Ginger (Zingiber officinale) rhizome.

    PubMed

    Kazeem, Mutiu Idowu; Akanji, Musbau Adewunmi; Yakubu, Musa Toyin

    2015-12-01

    Free and bound polyphenol extracts of Zingiber officinale rhizome were investigated for their antidiabetic potential in the pancreatic and renal tissues of diabetic rats at a dose of 500mg/kg body weight. Forty Wistar rats were completely randomized into five groups: A-E consisting of eight animals each. Group A (control) comprises normal healthy animals and were orally administered 1.0mL distilled water on a daily basis for 42 days while group B-E were made up of 50mg/kg streptozotocin (STZ)-induced diabetic rats. Group C and D received 1.0mL 500mg/kg body weight free and bound polyphenol extracts respectively while group E received 1.0mL 0.6mg/kg of glibenclamide. Administration of the extracts to the diabetic rats significantly reduced (p<0.05) serum glucose and urea concentrations, increased (p<0.05) serum insulin and Homeostatic Model Assessment for β-cell dysfunction (HOMA-β) while the level of creatinine and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) were not affected. Histological examination of the pancreas and kidney revealed restoration of the structural derangements caused by streptozotocin in the polyphenol extracts treated diabetic rats compared to the control groups. Therefore, polyphenols from Zingiber officinale could ameliorate diabetes-induced pancreatic and renal derangements in rats. PMID:26349770

  18. Effect of Aloe vera leaf gel and pulp extracts on the liver in type-II diabetic rat models.

    PubMed

    Can, Ayse; Akev, Nuriye; Ozsoy, Nurten; Bolkent, Sehnaz; Arda, Bahriye Pelin; Yanardag, Refiye; Okyar, Alper

    2004-05-01

    The aim of this work was to investigate the effects of Aloe vera leaf pulp and gel extracts on the liver tissue of neonatal streptozotocin (n0STZ)-induced type-II diabetic rats. The diabetic rats were separated into four groups and each group was given the following samples by gavage, daily for 15 d: phosphate buffered saline (PBS; diabetic control), Aloe leaf pulp extract, Aloe leaf gel extract, glibenclamide. Liver tissues were examined histologically. The markers of oxidative stress: glutathione (GSH), non-enzymatic glycosylation (NEG) and lipid peroxidation (LPO), were determined in liver tissue. Biochemical parameters for liver function: serum alkaline phosphatase (ALP), and alanine transaminase (ALP) activities, were evaluated. All parameters were also determined in healthy (non diabetic) rats for comparison. In the diabetic control group, the degenerative changes in liver tissue were remarkable, while in the diabetic groups given Aloe pulp and gel extracts and glibenclamide, the damage to the liver tissue was decreased. The increase of GSH and the decrease of NEG and LPO in liver tissues with the treatment of Aloe gel extract, is consistent with the beneficial effect of Aloe. Serum ALP and ALT activities were also decreased in the groups given Aloe gel extract. It was concluded that Aloe gel extract has a protective effect comparable to glibenclamide against hepatotoxicity produced by diabetes if used in the treatment of type-II diabetes. PMID:15133247

  19. Dietary fish oil inhibits mechanical allodynia and thermal hyperalgesia in diabetic rats by blocking nuclear factor-?B-mediated inflammatory pathways.

    PubMed

    Li, Meng-Ying; Wang, Ya-Yun; Cao, Rui; Hou, Xiang-Hong; Zhang, Lei; Yang, Rui-Hua; Wang, Feng

    2015-11-01

    One of the most common complications of early-onset diabetes mellitus is peripheral diabetic neuropathy, which is manifested either by loss of nociception or by allodynia and hyperalgesia. Diabetes mellitus is a common metabolic disease in human beings with characteristic symptoms of hyperglycemia, chronic inflammation and insulin resistance. Dietary fatty acids, especially polyunsaturated fatty acids, have been shown anti-inflammatory role in various experimental conditions. The present study investigated the effects of fish oil supplementation on the inflammation in the dorsal root ganglion (DRG) of streptozotocin (STZ)-induced diabetes rats. The effects of diabetes and fish oil treatment on the allodynia and hyperalgesia were also evaluated. Dietary fish oil effectively attenuated both allodynia and hyperalgesia induce by STZ injection. Along with the behavioral findings, DRG from fish oil-treated diabetic rats displayed a decrease in inflammatory cytokines and the expression of nuclear factor-?B (NF-?B) compared with untreated diabetic rats. Fish oil supplementation also increased the phosphorylation of AKT in DRG of diabetic rats. These results suggested that dietary fish oil-inhibited allodynia and hyperalgesia in diabetic rats may stem from its anti-inflammatory potential by regulating NF-?B and AKT. Fish oil might be useful as an adjuvant therapy for the prevention and treatment of diabetic complications. PMID:26118694

  20. Anti-diabetic effect of a preparation of vitamins, minerals and trace elements in diabetic rats: a gender difference

    PubMed Central

    2014-01-01

    Background Although multivitamin products are widely used as dietary supplements to maintain health or as special medical food in certain diseases, the effects of these products were not investigated in diabetes mellitus, a major cardiovascular risk factor. Therefore, here we investigated if a preparation of different minerals, vitamins, and trace elements (MVT) for human use affects the severity of experimental diabetes. Methods Two days old neonatal Wistar rats from both genders were injected with 100 mg/kg of streptozotocin or its vehicle to induce diabetes. At week 4, rats were fed with an MVT preparation or vehicle for 8 weeks. Well established diagnostic parameters of diabetes, i.e. fasting blood glucose and oral glucose tolerance test were performed at week 4, 8 and 12. Moreover, serum insulin and blood HbA1c were measured at week 12. Results An impaired glucose tolerance has been found in streptozotocin-treated rats in both genders at week 4. In males, fasting blood glucose and HbA1c were significantly increased and glucose tolerance and serum insulin was decreased at week 12 in the vehicle-treated diabetic group as compared to the vehicle-treated non-diabetic group. All of the diagnostic parameters of diabetes were significantly improved by MVT treatment in male rats. In females, streptozotocin treatment resulted in a less severe prediabetic-like phenotype as only glucose tolerance and HbA1c were altered by the end of the study in the vehicle-treated diabetic group as compared to the vehicle-treated non-diabetic group. MVT treatment failed to improve the diagnostic parameters of diabetes in female streptozotocin-treated rats. Conclusion This is the first demonstration that MVT significantly attenuates the progression of diabetes in male rats with chronic experimental diabetes. Moreover, we have confirmed that females are less sensitive to STZ-induced diabetes and MVT preparation did not show protection against prediabetic state. This may suggest a gender difference in the pathogenesis of diabetes. PMID:25160946

  1. Aqueous extract of tamarind seeds selectively increases glucose transporter-2, glucose transporter-4, and islets' intracellular calcium levels and stimulates ?-cell proliferation resulting in improved glucose homeostasis in rats with streptozotocin-induced diabetes mellitus.

    PubMed

    Sole, Sushant Shivdas; Srinivasan, B P

    2012-08-01

    Tamarindus indica Linn. has been in use for a long time in Asian food and traditional medicine for different diseases including diabetes and obesity. However, the molecular mechanisms of these effects have not been fully understood. In view of the multidimensional activity of tamarind seeds due to their having high levels of polyphenols and flavonoids, we hypothesized that the insulin mimetic effect of aqueous tamarind seed extract (TSE) might increase glucose uptake through improvement in the expression of genes of the glucose transporter (GLUT) family and sterol regulatory element-binding proteins (SREBP) 1c messenger RNA (mRNA) in the liver. Daily oral administration of TSE to streptozotocin (STZ)-induced (90 mg/kg intraperitoneally) type 2 diabetic male Wistar rats at different doses (120 and 240 mg/kg body weight) for 4 weeks showed positive correlation with intracellular calcium and insulin release in isolated islets of Langerhans. Tamarind seed extract supplementation significantly improved the GLUT-2 protein and SREBP-1c mRNA expression in the liver and GLUT-4 protein and mRNA expression in the skeletal muscles of diabetic rats. The elevated levels of serum nitric oxide (NO), glycosylated hemoglobin level (hemoglobin (A1c)) and tumor necrosis factor ? (TNF-?) decreased after TSE administration. Immunohistochemical findings revealed that TSE abrogated STZ-induced apoptosis and increased ?-cell neogenesis, indicating its effect on islets and ?-cell mass. In conclusion, it was found that the antidiabetic effect of TSE on STZ-induced diabetes resulted from complex mechanisms of ?-cell neogenesis, calcium handling, GLUT-2, GLUT-4, and SREBP-1c. These findings show the scope for formulating a new herbal drug for diabetes therapy. PMID:22935346

  2. Improvement of renal oxidative stress markers after ozone administration in diabetic nephropathy in rats

    PubMed Central

    2010-01-01

    Background Several complications of diabetes mellitus (DM) e.g. nephropathy (DN) have been linked to oxidative stress. Ozone, by means of oxidative preconditioning, may exert its protective effects on DN. Aim The aim of the present work is to study the possible role of ozone therapy in ameliorating oxidative stress and inducing renal antioxidant defence in streptozotocin (STZ)-induced diabetic rats. Methods Six groups (n = 10) of male Sprague Dawley rats were used as follows: Group C: Control group. Group O: Ozone group, in which animals received ozone intraperitoneally (i.p.) (1.1 mg/kg). Group D: Diabetic group, in which DM was induced by single i.p. injections of streptozotocin (STZ). Group DI: Similar to group D but animals also received subcutaneous (SC) insulin (0.75 IU/100 gm BW.). Group DO: In which diabetic rats received the same dose of ozone, 48 h after induction of diabetes. Group DIO, in which diabetic rats received the same doses of insulin and ozone, respectively. All animals received daily treatment for six weeks. At the end of the study period (6 weeks), blood pressure, blood glycosylated hemoglobin (HbA1c), serum creatinine, blood urea nitrogen (BUN), kidney tissue levels of superoxide dismutase (SOD), catalase (CAT), glutathione peroxide (GPx), aldose reductase (AR) activities and malondialdehyde (MDA) concentration were measured. Results Induction of DM in rats significantly elevated blood pressure, HbA1c, BUN, creatinine and renal tissue levels of MDA and AR while significantly reducing SOD, CAT and GPx activities. Either Insulin or ozone therapy significantly reversed the effects of DM on all parameters; in combination (DIO group), they caused significant improvements in all parameters in comparison to each alone. Conclusions Ozone administration in conjunction with insulin in DM rats reduces oxidative stress markers and improves renal antioxidant enzyme activity which highlights its potential uses in the regimen for treatment of diabetic patients. PMID:20465785

  3. The Relationship Between Inflammation and Impaired Wound Healing in a Diabetic Rat Burn Model.

    PubMed

    Tian, Ming; Qing, Chun; Niu, Yiwen; Dong, Jiaoyun; Cao, Xiaozan; Song, Fei; Ji, Xiaoyun; Lu, Shuliang

    2016-01-01

    Inflammation, initiated by polymorphonuclear neutrophil (PMNs) infiltration, is the first step in wound healing. The aim of this study is to investigate the function of neutrophils in a diabetes-impaired wound healing model and to explore the underlying mechanisms leading to neutrophil dysfunction. Superficial second-degree burns were created in the streptozotocin (STZ)-induced diabetic rat model, and the changes in the levels of advanced glycation end products (AGE), receptor of AGE (RAGE), inflammatory cytokines and oxidative markers, as well as cell apoptosis were determined. The effects of AGE on isolated PMNs were also determined in vitro. We found that deposition of AGE in diabetic rat skin activated the neutrophils before injury. However, the dense inflammatory band failed to form in the diabetic rats after injury. Compared with the controls, enhanced expression of RAGE and accelerated cell apoptosis were observed in the burned skin of diabetic rats. The altered expression pattern of inflammatory cytokines (tumor necrosis factor-alpha and interleukin-8) and oxidative markers (glutathione peroxidase, myeloperoxidase, hydrogen peroxide, and malondialdehyde) between burned skin of diabetic and control rats revealed delayed neutrophil chemotaxis and respiratory burst. Furthermore, the results in vitro showed that exposure to AGE inhibited the viability of PMNs, promoted RAGE production and cell apoptosis, and prevented the migration of PMNs, consistent with the findings in vivo. Besides, AGE-treated neutrophils showed increased secretion of inflammatory cytokines and increased oxidative stress. Combined, our results suggest that an interaction between AGE and its receptors inhibits neutrophil viability and function in the diabetic rat burn model. PMID:25407384

  4. Efficacy of Biodegradable Curcumin Nanoparticles in Delaying Cataract in Diabetic Rat Model

    PubMed Central

    Patil, Madhoosudan A.; Raghu, Ganugula; Balakrishna, Nagalla; Kumar, M. N. V. Ravi; Reddy, Geereddy Bhanuprakash

    2013-01-01

    Curcumin, the active principle present in the yellow spice turmeric, has been shown to exhibit various pharmacological actions such as antioxidant, anti-inflammatory, antimicrobial, and anti-carcinogenic activities. Previously we have reported that dietary curcumin delays diabetes-induced cataract in rats. However, low peroral bioavailability is a major limiting factor for the success of clinical utilization of curcumin. In this study, we have administered curcumin encapsulated nanoparticles in streptozotocin (STZ) induced diabetic cataract model. Oral administration of 2 mg/day nanocurcumin was significantly more effective than curcumin in delaying diabetic cataracts in rats. The significant delay in progression of diabetic cataract by nanocurcumin is attributed to its ability to intervene the biochemical pathways of disease progression such as protein insolubilization, polyol pathway, protein glycation, crystallin distribution and oxidative stress. The enhanced performance of nanocurcumin can be attributed probably to its improved oral bioavailability. Together, the results of the present study demonstrate the potential of nanocurcumin in managing diabetic cataract. PMID:24155984

  5. Changes in the function and ultrastructure of vessels in the rat model of multiple low dose streptozotocin-induced diabetes.

    PubMed

    Sotnikova, R; Skalska, S; Okruhlicova, L; Navarova, J; Kyselova, Z; Zurova, J; Stefek, M; Hozova, R; Nosalova, V

    2006-09-01

    In this study we investigated functional changes in the femoral artery and ultrastructural alterations in mesenteric vessels and capillaries in the rat model of multiple low dose streptozotocin (STZ)-induced diabetes. Participation of oxidative stress in this model of diabetes was established by studying the effect of the pyridoindole antioxidant stobadine (STB) on diabetes-induced impairment. Experimental diabetes was induced by i.v. bolus of STZ (20 mg/kg) given for three consecutive days to male rats. At the 12(th) week following STZ administration, the animals revealed typical signs of diabetes, such as polyphagia, polydypsia and polyuria. There was no weight gain in the diabetic groups throughout the experiment. No exitus occurred in any group. Diabetes was characterised with high levels of plasma glucose, no significant changes in lipid metabolism, decreased serum levels of glutathione, increased serum levels of the lysosomal enzyme N-acetyl-beta-D-glucosaminidase (NAGA), injured endothelial relaxant capacity of the femoral artery and alterations in ultrastructure of mesenteric arteries and capillaries. Antioxidant STB in the dose of 25 mg/kg body weight i.p. (5 times per week) did not influence glucose levels, however, it mitigated biochemical, functional and ultrastructural changes induced by diabetes, suggesting a role of reactive oxygen species in diabetes-induced tissue damage. PMID:17197727

  6. GC-MS analysis and screening of antidiabetic, antioxidant and hypolipidemic potential of Cinnamomum tamala oil in streptozotocin induced diabetes mellitus in rats

    PubMed Central

    2012-01-01

    Aim of the study This study was made to investigate the antidiabetic, antioxidant and hypolipidemic potential of Cinnamomum tamala, (Buch.-Ham.) Nees & Eberm (Tejpat) oil (CTO) in streptozotocin (STZ) induced diabetes in rats along with evaluation of chemical constituents. Materials and methods The GC-MS (Gas chromatographymass spectrometry) analysis of the oil showed 31 constituents of which cinnamaldehyde was found the major component (44.898%). CTO and cinnamaldehyde was orally administered to diabetic rats to study its effect in both acute and chronic antihyperglycemic models. The body weight, oral glucose tolerance test and biochemical parameters viz. glucose level, insulin level, liver glycogen content, glycosylated hemoglobin, total plasma cholesterol, triglyceride and antioxidant parameters were estimated for all treated groups and compared against diabetic control group. Results CTO (100?mg/kg and 200?mg/kg), cinnamaldehyde (20?mg/kg) and glibenclamide (0.6?mg/kg) in respective groups of diabetic animals administered for 28?days reduced the blood glucose level in streptozotocin induced diabetic rats. There was significant increase in body weight, liver glycogen content, plasma insulin level and decrease in the blood glucose, glycosylated hemoglobin and total plasma cholesterol in test groups as compared to control group. The results of CTO and cinnamaldehyde were found comparable with standard drug glibenclamide. In vitro antioxidant studies on CTO using various models showed significant antioxidant activity. In vivo antioxidant studies on STZ induced diabetic rats revealed decreased malondialdehyde (MDA) and increased reduced glutathione (GSH). Conclusion Thus the investigation results that CTO has significant antidiabetic, antioxidant and hypolipidemic activity. PMID:22882757

  7. Effect of Alpinia calcarata on glucose uptake in diabetic rats-an in vitro and in vivo model

    PubMed Central

    2014-01-01

    Background Diabetes mellitus is a heterogeneous metabolic disorders characterized by abnormally high levels of blood glucose The main objective of the present work is to study the effect of Alpinia calcarata on glucose uptake in streptozotocin (STZ) induced diabetic rats. Methods The diabetes was induced by single dose of STZ (45 mg/kg) in citrate buffer, while the normal control group was given the vehicle (citrate buffer) only. After induction of diabetes, the diabetic animals were treated with ethanolic extract of Alpinia calcarata (200 mg/kg) and glibenclamide (2 mg/kg) for 30 days. Blood glucose estimation was performed every week of the study. At the end of study period, animals were sacrificed for biochemical studies. Results Streptozotocin induced diabetic rats shows the altered levels of various biochemical profiles. Those levels were brought back to near normal upon treatment with ethanolic extract of Alpinia calcarata and standard drug glibanclamide. No significant changes were observed on treatment with plant extract alone group indicated that there are no toxic substances present in Alpinia calcarata. The antidiabetic activity of plant extract was also further confirmed by histopathological studies. The ethanolic extract of Alpinia calcarata shows significant inhibition of alpha glucosidase activity and also enhancing the glucose uptake in rat hemidiaphragm. Conclusions In conclusion, the ethanolic extract of Alpinia calcarata ameliorates the condition associated with diabetes. PMID:24502532

  8. Cardiac contractile dysfunction and apoptosis in streptozotocin-induced diabetic rats are ameliorated by garlic oil supplementation.

    PubMed

    Ou, Hsiu-Chung; Tzang, Bor-Show; Chang, Mu-Hsin; Liu, Cheng-Tzu; Liu, Hui Wen; Lii, Chong-Kuei; Bau, Da-Tian; Chao, Pei-Min; Kuo, Wei-Wen

    2010-10-13

    Previous studies have suggested that garlic oil could protect the cardiovascular system. However, the mechanism by which garlic oil protects diabetes-induced cardiomyopathy is unclear. In this study, streptozotocin (STZ)-induced diabetic rats received garlic oil (0, 10, 50, or 100 mg/kg of body weight) by gastric gavage every 2 days for 16 days. Normal rats without diabetes were used as control. Cardiac contractile dysfunction examined by echocardiography and apoptosis evaluated by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay were observed in diabetic rat hearts. Additionally, a shift in cardiac myosin heavy chain (MHC) gene expression from ?- to ?-MHC isoform, decreased levels of superoxide dismutase-1 (SOD-1) and cardiac ?-actin, and elevated cardiac thiobarbituric acid reactive substances (TBARS) and caspase- and p38-NF?B-leading apoptosis signaling activities were demonstrated in diabetic hearts. However, these diabetes-related cardiac dysfunctions were almost dose-dependently ameliorated by garlic oil administration. In conclusion, garlic oil possesses significant potential for protecting hearts from diabetes-induced cardiomyopathy. PMID:20836552

  9. Docosahexaenoic acid inhibits mechanical allodynia and thermal hyperalgesia in diabetic rats by decreasing the excitability of DRG neurons.

    PubMed

    Heng, Li-Jun; Qi, Rui; Yang, Rui-Hua; Xu, Guo-Zheng

    2015-09-01

    Diabetes mellitus is a common metabolic disease in human beings with characteristic symptoms of hyperglycemia, chronic inflammation and insulin resistance. One of the most common complications of early-onset diabetes mellitus is peripheral diabetic neuropathy, which is manifested either by loss of nociception or by allodynia and hyperalgesia. Dietary fatty acids, especially polyunsaturated fatty acids, have been shown the potential of anti-inflammation and modulating neuron excitability. The present study investigated the effects of docosahexaenoic acid (DHA) on the excitability of dorsal root ganglion (DRG) neurons in streptozotocin (STZ)-induced diabetes rats. The effects of DHA on the allodynia and hyperalgesia of diabetic rats were also evaluated. Dietary DHA supplementation effectively attenuated both allodynia and hyperalgesia induced by STZ injection. DHA supplementation decreased the excitability of DRG neurons by decreasing the sodium currents and increasing potassium currents, which may contribute to the effect of alleviating allodynia and hyperalgesia in diabetic rats. The results suggested that DHA might be useful as an adjuvant therapy for the prevention and treatment of painful diabetic neuropathy. PMID:26118950

  10. Quantitative-profiling of neurotransmitter abnormalities in the disease progression of experimental diabetic encephalopathy rat.

    PubMed

    Zhou, Xueyan; Zhu, Qiuxiang; Han, Xiaowen; Chen, Renguo; Liu, Yaowu; Fan, Hongbin; Yin, Xiaoxing

    2015-11-01

    Diabetic encephalopathy (DE) is one of the most prevalent chronic complications of diabetes mellitus (DM), with neither effective prevention nor proven therapeutic regimen. This study aims to uncover the potential dysregulation pattern of the neurotransmitters in a rat model of streptozotocin (STZ)-induced experimental DE. For that purpose, male Sprague-Dawley (SD) rats were treated with a single intraperitoneal injection of STZ. Cognitive performance was detected with the Morris water maze (MWM) test. Serum, cerebrospinal fluid (CSF), and brain tissues were collected to measure the levels of neurotransmitters. Compared with the control rats, the acetylcholine (ACh) levels in serum, CSF, hippocampus, and cortex were all significantly down-regulated as early as 6 weeks in the STZ treatment group. In contrast, the glutamate (Glu) levels were decreased in CSF and the hippocampus, but unaffected in the serum and cortex of STZ-treated rats. As for ?-aminobutyric acid (GABA), it was down-regulated in serum, but up-regulated in CSF, hippocampus, and the cortex in the STZ-treated group. The mRNA expressions of neurotransmitter-related rate limiting enzymes (including AChE, GAD1, and GAD2) and pro-inflammatory cytokines (including IL-1? and TNF-?) were all increased in the DE rats. Our data suggest that DM induces isoform-dependent and tissue-specific neurotransmitter abnormalities, and that neuroinflammation may underlay the nervous system dysfunction observed in the progression of DE. PMID:26426748

  11. Bioactive fraction of Saraca indica prevents diabetes induced cataractogenesis: An aldose reductase inhibitory activity

    PubMed Central

    Somani, Gauresh; Sathaye, Sadhana

    2015-01-01

    Background: The present study was designed to investigate the effect of Saraca indica (SI) flowers extract and different bioactive fraction on in vitro aldose reductase (AR) inhibitory activity, high glucose-induced cataract in goat lens and in vivo streptozotocin (STZ; 45 mg/kg, i.p) induced cataract in rats. Methods: Extract of flowers of SI tested for inhibition against rat lens AR. Furthermore, bioactive fraction was investigated against high glucose-induced opacification of the lens in vitro lens culture and STZ induced diabetic cataract in rats. Identification of the bioactive component was attempted through high-performance thin-layer chromatography, high-performance liquid chromatography and liquid chromatography-mass spectrometry analysis. Results: Ethyl acetate fraction of S. indica (EASI) produced maximum inhibition that may be due to high phenolic content. Goat lenses in media containing glucose developed a distinctly opaque ring in 72 h and treatment with EASI fraction lowered lens opacity in 72 h. Prolonged treatment with EASI to STZ-induced diabetic rats inhibited the AR activity and delayed cataract progression in a dose dependent manner. Conclusion: Ethyl acetate fraction of S. indica fraction has potential to inhibit rat lens AR enzyme and prevent cataractogenesis not only in goat lens model (in vitro), but also in STZ induced diabetic rats (in vivo). This study is suggestive of the anticataract activity of EASI fraction that could be attributed to the phytoconstituents present in the same. PMID:25709218

  12. Evaluation of Antihyperglycemic Activity of Citrus limetta Fruit Peel in Streptozotocin-Induced Diabetic Rats

    PubMed Central

    KunduSen, Sriparna; Haldar, Pallab K.; Gupta, Malaya; Mazumder, Upal K.; Saha, Prerona; Bala, Asis; Bhattacharya, Sanjib; Kar, Biswakanth

    2011-01-01

    The present paper aims to evaluate antihyperglycemic activity of methanol extract of Citrus limetta fruit peel (MECL) in streptozotocin-induced (STZ; 65?mg/kg b.w.) diabetic rats. Three days after STZ induction, diabetic rats received MECL orally at 200 and 400?mg kg?1 body weight daily for 15 days. Glibenclamide (0.5?mg kg?1 p. o.) was used as reference drug. Blood glucose levels were measured on 0th, 4th, 8th, and 15th days of study. Serum biochemical parameters namely, SGOT, SGPT and ALP were estimated. The TBARS and GSH levels of pancreas, kidney, and liver were determined. MECL significantly (P < 0.001) and dose dependently normalized blood glucose levels and serum biochemical parameters, decreased lipid peroxidation, and recovered GSH as compared to those of STZ control. The present paper infers that in STZ-induced diabetic Wistar rats, C. limetta fruit peel demonstrated a potential antihyperglycemic effect which may be attributed to its antioxidant property. PMID:22363893

  13. Dual Blockade of Renin Angiotensin System in Reducing the Early Changes of Diabetic Retinopathy and Nephropathy in a Diabetic Rat Model

    PubMed Central

    Thangaraju, Pugazhenthan; Chakrabarti, Amitava; Banerjee, Dibyajyoti; Hota, Debasish; Tamilselvan; Bhatia, Alka; Gupta, Amod

    2014-01-01

    Background: Diabetes mellitus is a real pandemic of the modern world and the incidence of the disease is increasing at a tremendous rate with a number of complications involving major systems of the human body. The renin angiotensin system (RAS) is considered to be involved in most of the pathological processes that result in diabetic nephropathy and retinopathy. Aim: The study was designed to evaluate and compare effects of ramipril (angiotensin-converting enzyme inhibitor-ACEI) and telmisartan (angiotensin II receptor blocker - ARBs) combinations on the progression of retinopathy and nephropathy in the streptozotocin (STZ) induced diabetic model. Materials and Methods: Diabetic state in rats was induced by chemical method using STZ 55 mg/kg intraperitoneally. Diabetic renal tubulopathy and interstitial inflammatory changes were done. Diabetic retinopathy manifested in the form of vacuolar changes in the inner plexiform and the ganglionic layers of the retina was observed. Results: Treatments with ACEI and ARBs reduced the incidence of the occurrence of cataract. The effect of combinational drugs of ACEI (ramipril) and AT1 receptor blocker (Telmisartan) was evaluated. The drugs used in combinations showed improvement in the histopathological and biochemical changes of the diabetic animals, both for the retina and kidney. Conclusion: The efficacy of the drugs suggests a pivotal role of the local RAS system in the pathogenesis of tubulopathy in the kidney and neuronal damage in the retina of the diabetic animals. PMID:25599050

  14. Herbal formulation, DIA-2 and Rosiglitazone ameliorates hyperglycemia and hepatic steatosis in type 2 diabetic rats.

    PubMed

    Kesavanarayanan, K S; Priya, R J; Selvakkumar, C; Kavimani, S; Prathiba, D

    2015-08-01

    DIA-2 is a herbal mixture containing standardized extract of Allium sativum and Lagerstroemia speciosa. Recently we have reported the anti-diabetic effect of DIA-2 in high fat diet (HFD) and streptozotocin (STZ) induced type 2 diabetic (T2D) rats. The purpose of this study was to investigate and compare the effects of DIA-2 with Rosiglitazone (RG) on plasma biomarkers of hepatocellular injury, liver carbohydrate metabolizing enzymes, glycogen content, oxidant/antioxidant status and histopathological changes in T2D rats. ALT and ALP levels were significantly decreased after DIA-2 and RG treatment compared to T2D rats. Total protein and albumin remained unaltered in all the groups. Significant decrease in AST levels were observed after DIA-2 (125 mg/kg) and RG treatment. Hepatic hexokinase activity was significantly increased after RG and DIA-2 treatment and fructose-1, 6-bisphosphatase activity were inversely correlated with hexokinase activity. Hepatic gucose-6-phosphatase activity was significantly (p < 0.05) reduced after DIA-2 (62.5 mg/kg) and RG treatment. Lipid peroxides levels was significantly decreased in the liver of DIA-2 (62.5; p < 0.01 & 125 mg/kg; p < 0.05) treated animals. Hepatic glycogen content (p < 0.05) and antioxidant enzymes [SOD (p < 0.01; 62.5 mg/kg); GPx and GSH (125 mg/kg; p < 0.01)] were significantly increased after DIA-2 treatment. RG treatment on hepatic glycogen, GPx (p < 0.01) and SOD, GSH (p < 0.05) levels were significant when compared to T2D rats. These biochemical parameters were also correlated with histopathological evaluation. The above findings revealed that administration of DIA-2 could ameliorate the biochemical and histopathological changes in liver of T2D rats indicating the protective role of DIA-2 against HFD/STZ induced diabetes. In addition, DIA-2 and RG treatment resulted in amelioration of hepatic steatosis in T2D rats. PMID:26367735

  15. Taurine attenuates maternal and embryonic oxidative stress in a streptozotocin-diabetic rat model.

    PubMed

    Shivananjappa, Mahesh Mysore; Muralidhara

    2012-05-01

    Oxidative stress mechanisms have been implicated in congenital anomalies and morbidity/mortality of fetus/newborn in diabetic pregnancy. Numerous antioxidant treatments have shown varied beneficial effects in improving both maternal and fetal outcomes. The present study examined the propensity of taurine to attenuate the degree of embryopathy and oxidative stress among pregnant diabetic rats. Adult rats (CFT-Wistar) were rendered diabetic with an acute dose of streptozotocin (STZ; 45 mg/kg bodyweight) on gestation day (GD) 4. Both Diabetic and non-diabetic dams were given oral supplements of taurine (0.5 and 1g/kg bodyweight/day) from GD 5 to GD 12. Maternal diet intake, bodyweight gain and urine output were monitored and dams were killed on GD 13. Markers of oxidative stress were determined in embryos and maternal livers. STZ treatment induced marked embryopathy (32%) and taurine supplements markedly reduced the degree of embryopathy (54% protection). The STZ-induced higher oxidative stress was significantly attenuated in rats given taurine supplements (P<0.05) and a similar effect was seen in embryos (P<0.05). These data suggest that dietary taurine during pregnancy provides significant protection against diabetes-induced oxidative stress in both the mother and the embryos and thus may serve as a therapeutic supplement during diabetic pregnancy. Diabetes during pregnancy affects >5% of all pregnancies, causing reproductive abnormalities that enhance spontaneous abortion - congenital anomalies, morbidity and mortality of both mother and fetus/newborn. One of the major mechanisms is increased oxidative stress caused by hyperglycaemia and the most prominent anti-teratogenic effect was achieved using antioxidative agents. Management of oxidative stress is considered, along with tight glycaemic control, to be beneficial both before conception and during pregnancy. Taurine, a ubiquitous amino acid found in almost all mammalian tissues, constitutes more than 50% of free amino acids. The aim of the study was to determine whether oral taurine supplementation given to pregnant diabetic rats during the post-implantation period could reduce embryo lethality and protect the developing embryos against maternal hyperglycaemia-induced oxidative stress. Adult rats were rendered diabetic with an acute dose of streptozotocin on gestation day (GD) 4. Both diabetic and non-diabetic dams were administered oral taurine for a period of 8 days (GD 5-13). Maternal diet intake, bodyweight gain and urine output were monitored and dams were killed on GD 13. Markers of oxidative stress and antioxidant defences were studied in embryos and maternal livers. STZ induced marked embryopathy (32%) and taurine supplementation offered significant protection (54%). Taurine significantly offset diabetes-associated oxidative stress in the embryos of diabetic rats. These data suggest that dietary taurine supplementation during pregnancy provides significant protection against diabetes-induced oxidative stress both in mother and embryos and thus may serve as a therapeutic supplement under diabetic pregnancy. PMID:22414371

  16. Ruscogenin ameliorates diabetic nephropathy by its anti-inflammatory and anti-fibrotic effects in streptozotocin-induced diabetic rat

    PubMed Central

    2014-01-01

    Background Ruscogenin is a major steroid sapogenin in the traditional Chinese herb Ophiopogon japonicus that have multiple bioactivities. Recent studies have demonstrated that ruscogenin is involved in down-regulation of intercellular adhesion molecule-1 (ICAM-1) and nuclear factor-?B (NF-?B) activation in anti-inflammatory pathways. We hypothesized that ruscogenin protects against diabetic nephropathy (DN) by inhibiting NF-?B-mediated inflammatory pathway. To test this hypothesis, the present study was to examine the effects of ruscogenin in rats with streptozotocin (STZ)-induced DN. Methods Diabetes was induced with STZ (60mg/kg) by intraperitoneal injection in rats. Two weeks after STZ injection, rats in the treatment group were orally dosed with 0.3, 1.0 or 3.0mg/kg ruscogenin for 8weeks. The normal rats were chosen as nondiabetic control group. The rats were sacrificed 10weeks after induction of diabetes. Changes in renal function-related parameters in plasma and urine were analyzed at the end of the study. Kidneys were isolated for pathology histology, immunohistochemistry, and Western blot analyses. Results Ruscogenin administration did not lower the levels of plasma glucose and glycosylated hemoglobin in STZ-diabetic rats. Diabetic rats exhibited renal dysfunction, as evidenced by reduced creatinine clearance, blood urea nitrogen and proteinuria, along with marked elevation in the ratio of kidney weight to body weight, that were reversed by ruscogenin. Ruscogenin treatment was found to markedly improve histological architecture in the diabetic kidney. Renal NF-?B activity, as wells as protein expression and infiltration of macrophages were increased in diabetic kidneys, accompanied by an increase in protein content of intercellular adhesion molecule-1 and monocyte chemoattractant protein-1 in kidney tissues. All of the above abnormalities were reversed by ruscogenin treatment, which also decreased the expression of transforming growth factor-?1 and fibronectin in the diabetic kidneys. Conclusions Our data demonstrated that ruscogenin suppressed the inflammation and ameliorated the structural and functional abnormalities of the diabetic kidney in rats might be associated with inhibition of NF-?B mediated inflammatory genes expression. PMID:24666993

  17. Effects of a new advanced glycation inhibitor, LR-90, on mitigating arterial stiffening and improving arterial elasticity and compliance in a diabetic rat model: aortic impedance analysis

    PubMed Central

    Satheesan, S; Figarola, J L; Dabbs, T; Rahbar, S; Ermel, R

    2014-01-01

    BACKGROUND AND PURPOSE We determined the effects of treatment with LR-90, an inhibitor of advanced glycation end products, on the mechanical properties of the arterial system in streptozotocin (STZ)-induced diabetic Sprague Dawley rats, using aortic impedance analysis, and further investigated the effects of LR-90 on the progression of aortic pathology. EXPERIMENTAL APPROACH STZ-induced diabetic rats were treated with or without LR-90 (50 mg L-1 in drinking water) for 8 weeks and compared with control groups. Arterial BP measurements, various metabolic parameters, aortic histopathology, collagen cross-linking, AGE accumulation, and RAGE protein expression in aortic tissue were determined. Pulsatile parameters were evaluated using a standard Fourier series expansion technique and impulse response function of the filtered aortic input impedance spectra. KEY RESULTS LR-90 reduced glycated haemoglobin and triglycerides levels, although it had no effect on the glycaemic status. LR-90 did not affect arterial BP, but prevented the diabetes-induced increase in peripheral resistance and variations in aortic distensibility, as it reduced aortic characteristic impedance by 21%. LR-90 also prevented the elevation in wave reflection factor, as indicated by a 22.5% reduction and an associated increase of 23.5% in wave transit time, suggesting it prevents the augmentation of the systolic load of the left ventricle. Moreover, LR-90 inhibited collagen cross-linking and the accumulation of AGE and RAGE in the vasculature of diabetic rats. CONCLUSIONS AND IMPLICATIONS Treatment with LR-90 may impart significant protection against diabetes-induced aortic stiffening and cardiac hypertrophy and provides an additional therapeutic option for treatment of AGE associated diabetic complications. PMID:24611770

  18. Comparative Proteomics Study of Streptozotocin-induced Diabetic Nephropathy in Rats Kidneys Transfected with Adenovirus-mediated Fibromodulin Gene

    PubMed Central

    Maleki, Akram; Ramazani, Ali; Foroutan, Maryam; Biglari, Alireza; Ranjzad, Parisa; Mellati, Ali Awsat

    2014-01-01

    Background Transforming Growth Factor-beta (TGF-?) activation appears to be crucial for tissue injury in Diabetic Nephropathy (DN). Fibromodulin, the small leucine-rich proteoglycan, has been proposed to be the potent TGF-? modulator. In this study, the therapeutic effects of fibromodulin in the kidneys of streptozotocin (STZ)-induced diabetic rats were investigated. Methods Diabetic rats received intraperitoneal (IP) injections of recombinant adenovirus expression vectors (RAd5) containing fibromodulin (RAd-FMOD) and were killed after 10 weeks. Proteins were isolated from the rat kidney and separated using two-dimensional gel electrophoresis. The differentially expressed proteins were analyzed using Matrix-assisted laser desorption/ ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Results Ten spots were identified using MALDI-TOF-MS. The identified proteins were primarily responsible for cell metabolism, cytoskeleton formation, and oxidative stress. RAd-FMOD treatment markedly attenuated the albuminuria in diabetic rats. Conclusion Taken together, these results provide a valuable clue in exploring the mechanism underlying the therapeutic effects of fibromodulin in diabetic nephropathy suggesting that it can be a potential agent in the treatment of this disease. PMID:24834312

  19. Oxcarbazepine antinociception in animals with inflammatory pain or painful diabetic neuropathy.

    PubMed

    Kiguchi, Sumiyoshi; Imamura, Takahiro; Ichikawa, Kiyoshi; Kojima, Masami

    2004-01-01

    1. Diabetic neuropathy is one of the most frequent complications of diabetes mellitus. However, the mechanisms underlying these disorders are not yet well defined and it has been reported that currently available analgesics have hardly any ameliorating effect on painful diabetic neuropathy. 2. The purpose of the present study was to evaluate the antinociceptive effect of oxcarbazepine (OCBZ), a keto derivative of carbamazepine (CBZ), in animal models generally used in pain research and in rats and mice with streptozotocin (STZ)-induced diabetes. In addition, we compared the effect of OCBZ with those of CBZ, mexiletine and morphine. 3. Diabetes was induced by injection of STZ at a dose of 300 mg/kg (i.p.) in mice and 50 mg/kg (i.v.) in rats. Experiments were conducted 2 weeks after STZ injection and those animals with a serum glucose level above 400 mg/dL were used for data analysis. Antinociceptive effects of the drugs were evaluated by the paw withdrawal test (normal, STZ-induced diabetic and carrageenin-injected rats), tail-flick test (normal and STZ-induced diabetic mice) and nociceptive behaviour (formalin-injected mice). 4. In the present study, diabetic mice showed thermal hyperalgesia and diabetic rats exhibited mechanical hyperalgesia. From these results, the STZ-induced diabetic animals used in the present study were found to be suitable for research on painful diabetic neuropathy. In STZ-induced diabetic animals, the antinociceptive effects of OCBZ, CBZ and mexiletine were facilitated, whereas the effect of morphine was attenuated, compared with effects in normal animals. 5. Oxcarbazepine inhibited the formalin-induced biphasic pain responses and increased the nociceptive threshold in the case of carrageenin-induced hyperalgesia. In view of these results, inhibition of substance P-mediated pain transmission may be involved in the antinociceptive action of OCBZ. 6. These results indicate that OCBZ has an analgesic action and is a possible therapeutic agent for the treatment of neuropathic pain, such as occurs in painful diabetic neuropathy. PMID:14756685

  20. Insulin treatment restores glutamate (?-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) receptor function in the hippocampus of diabetic rats.

    PubMed

    Viswaprakash, Nilmini; Vaithianathan, Thirumalini; Viswaprakash, Ajitan; Judd, Robert; Parameshwaran, Kodeeswaran; Suppiramaniam, Vishnu

    2015-09-01

    Type 1 diabetes is associated with cognitive dysfunction. Cognitive processing, particularly memory acquisition, depends on the regulated enhancement of expression and function of glutamate receptor subtypes in the hippocampus. Impairment of memory was been detected in rodent models of type 1 diabetes induced by streptozotocin (STZ). This study examines the functional properties of synaptic ?-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors and the expression of synaptic molecules that regulate glutamatergic synaptic transmission in the hippocampus of STZ-diabetic rats. The AMPA receptor-mediated miniature excitatory postsynaptic currents (mEPSCs) and single-channel properties of synaptosomal AMPA receptors were examined after 4 weeks of diabetes induction. Results show that amplitude and frequency of mEPSCs recorded from CA1 pyramidal neurons were decreased in diabetic rats. In addition, the single-channel properties of synaptic AMPA receptors from diabetic rat hippocampi were different from those of controls. These impairments in synaptic currents gated by AMPA receptors were accompanied by decreased protein levels of AMPA receptor subunit GluR1, the presynaptic protein synaptophysin, and the postsynaptic anchor protein postsynaptic density protein 95 in the hippocampus of diabetic rats. Neural cell adhesion molecule (NCAM), an extracellular matrix molecule abundantly expressed in the brain, and the polysialic acid (PSA) attached to NCAM were also downregulated in the hippocampus of diabetic rats. Insulin treatment, when initiated at the onset of diabetes induction, reduced these effects. These findings suggest that STZ-induced diabetes may result in functional deteriorations in glutamatergic synapses in the hippocampus of rats and that these effects may be reduced by insulin treatment. PMID:25807926

  1. Antidiabetic and Hypolipidemic Effect of Salacia Oblonga in Streptozotocin Induced Diabetic Rats

    PubMed Central

    Bhat, Bhagyajyothi M.; C.V., Raghuveer; D’Souza, Vivian; Manjrekar, Poornima A.

    2012-01-01

    Objectives The present study was conducted to evaluate the effect of a standardized hydroalcoholic root extract of Sala¬cia oblonga (SOE) on the Random Blood Glucose (RBG) levels, serum insulin, glycated haemoglobin (HbA1c) and the serum lipid profile in long standing, experimentally induced Diabetes Mellitus (DM) with glibenclamide (Glb) as the standard. Materials and Methods Streptozotocin (STZ) induced, dia-betic, Wistar rats of either sex were treated with two oral doses of SOE, 100 and 50mg/kg body wt /day, for a period of 16 weeks. The RBG was estimated at day-1 and at the end of the 16 weeks by using a glucometer. The fasting serum insulin was determined by an ELISA technique. The plasma HbA1c was evaluated by a Turbidimetric Inhibition Immunoassay (TINIA) and the lipid profile was estimated enzymatically. Results and Analysis A 45% decrease in the RBG was seen after the treatment with the higher dose of SOE, whereas a 44% decrease was observed with the lower dose as com¬pared to the diabetic control. Serum insulin was significantly increased (P<0.05) in all the treated groups as compared to the diabetic control. Plasma HbA1c was significantly decreased (P<0.05). The serum Triacyl Glycerol (TG) levels were signifi¬cantly decreased (P<0.05) in the treated rats as compared to the diabetic control. A significant increase in HDL-cholesterol (P<0.05) in the diabetic rats as a result of the 100mg/kg SOE treatment was a remarkable finding. Conclusion SOE improves the glycaemic parameters in diabetic rats after a prolonged treatment. The serum TG levels were normalized on treatment. A higher dose of the extract could not alter the parameters significantly, except for HDL-C. PMID:23373028

  2. Zinc supplementation ameliorates glycoprotein components and oxidative stress changes in the lung of streptozotocin diabetic rats.

    PubMed

    Sacan, Ozlem; Turkyilmaz, Ismet Burcu; Bayrak, Bertan Boran; Mutlu, Ozgur; Akev, Nuriye; Yanardag, Refiye

    2016-04-01

    Zinc (Zn) is a component of numerous enzymes that function in a wide range of biological process, including growth, development, immunity and intermediary metabolism. Zn may play a role in chronic states such as cardiovascular disease and diabetes mellitus. Zn acts as cofactor and for many enzymes and proteins and has antioxidant, antiinflammatory and antiapoptotic effects. Taking into consideration that lung is a possible target organ for diabetic complications, the aim of this study was to investigate the protective role of zinc on the glycoprotein content and antioxidant enzyme activities of streptozotocin (STZ) induced diabetic rat tissues. Female Swiss albino rats were divided into four groups. Group I, control; Group II, control + zinc sulfate; Group III, STZ-diabetic; Group IV, diabetic + zinc sulfate. Diabetes was induced by intraperitoneal injection of STZ (65 mg/kg body weight). Zinc sulfate was given daily by gavage at a dose of 100 mg/kg body weight every day for 60 days to groups II and IV. At the last day of the experiment, rats were sacrificed, lung tissues were taken. Also, glycoprotein components, tissue factor (TF) activity, protein carbonyl (PC), advanced oxidative protein products (AOPP), hydroxyproline, and enzyme activities in lung tissues were determined. Glycoprotein components, TF activity, lipid peroxidation, non enzymatic glycation, PC, AOPP, hydroxyl proline, lactate dehydrogenase, catalase, superoxide dismutase, myeloperoxidase, xanthine oxidase, adenosine deaminase and prolidase significantly increased in lung tissues of diabetic rats. Also, glutathione levels, paraoxonase, arylesterase, carbonic anhydrase, and Na(+)/K(+)- ATPase activities were decreased. Administration of zinc significantly reversed these effects. Thus, the study indicates that zinc possesses a significantly beneficial effect on the glycoprotein components and oxidant/antioxidant enzyme activities. PMID:26817646

  3. Restoration of direct pathway glycogen synthesis flux in the STZ-diabetes rat model by insulin administration.

    PubMed

    Soares, Ana F; Carvalho, Rui A; Veiga, Francisco J; Alves, Marco G; Martins, Ftima O; Viegas, Ivan; Gonzlez, Juan D; Metn, Isidoro; Baanante, Isabel V; Jones, John G

    2012-10-01

    Type 1 diabetes subjects are characterized by impaired direct pathway synthesis of hepatic glycogen that is unresponsive to insulin therapy. Since it is not known whether this is an irreversible defect of insulin-dependent diabetes, direct and indirect pathway glycogen fluxes were quantified in streptozotocin (STZ)-induced diabetic rats and compared with STZ rats that received subcutaneous or intraperitoneal insulin (I-SC or I-IP). Three groups of STZ rats were studied at 18 days post-STZ treatment. One group was administered I-SC and another I-IP as two daily injections of short-acting insulin at the start of each light and dark period for days 9-18. A third group did not receive any insulin, and a fourth group of nondiabetic rats was used as control. Glycogen synthesis via direct and indirect pathways, de novo lipogenesis, and gluconeogenesis were determined over the nocturnal feeding period using deuterated water. Direct pathway was residual in STZ rats, and glucokinase activity was also reduced significantly from control levels. Insulin administration restored both net glycogen synthesis via the direct pathway and glucokinase activity to nondiabetic control levels and improved the lipogenic pathway despite an inefficient normalization of the gluconeogenic pathway. We conclude that the reduced direct pathway flux is not an irreversible defect of insulin-dependent diabetes. PMID:22850684

  4. Palmitoylethanolamide treatment reduces retinal inflammation in streptozotocin-induced diabetic rats.

    PubMed

    Paterniti, Irene; Di Paola, Rosanna; Campolo, Michela; Siracusa, Rosalba; Cordaro, Marika; Bruschetta, Giuseppe; Tremolada, Gemma; Maestroni, Anna; Bandello, Francesco; Esposito, Emanuela; Zerbini, Gianpaolo; Cuzzocrea, Salvatore

    2015-12-15

    Although the pathogenesis of diabetic retinopathy (DR) is still insufficiently understood, new evidences indicate 'retinal inflammation' as an important player in the pathogenesis of the complication. Accordingly, common sets of upregulated inflammatory cytokines are found in serum, vitreous and aqueous samples obtained from subjects with DR, and these cytokines can have multiple interactions to impact the pathogenesis of the disease. Thus, based on previously published data, we investigated the effects of Palmitoylethanolamide (PEA), an endogenous lipid amide that belongs to the N-acyl-ethanolamines family, on DR in streptozotocin (STZ)-induced diabetic rats. PEA (10mg/kg) was administered orally daily starting 3 days after the iv administration of STZ. The rats were killed 15 and 60day later and eyes were enucleated to evaluate, through immunohistochemical analysis, the key inflammatory events involved in the breakdown of blood retinal barrier (BRB). Immunohistochemical analysis confirmed the presence of VEGF, ICAM-1, nitrotyrosine (a marker of peroxynitrite), and tight junctions in the retina of STZ-treated rats. Of interest, the extent of injury was significantly reduced after treatment with PEA. Altogether, this study provides the first evidence that PEA attenuates the degree of inflammation while preserving the blood-retinal barrier in rats with experimental DR. PMID:26607470

  5. [The influence of mildronate on peripheral neuropathy and some characteristics of glucose and lipid metabolism in rat streptozotocin-induced diabetes mellitus model].

    PubMed

    Sokolovska, J; Rumaks, J; Karajeva, N; Gr?nvalde, D; Shapirova, J; Klua, V; Kalvinsh, I; Sjakste, N

    2011-01-01

    Streptozotocin (STZ) was used to induce the diabetic rat model. STZ rats were treated with mildronate (100 mg/kg daily, per os or intraperitoneally for 6 weeks). Body weight, blood glucose, triglyceride, ketone body concentrations, glycated hemoglobin percent (HbA1c%), glucose tolerance, and the development of neuropathic pain were monitored throughout the experiment. In the STZ + mildronate group, mildronate treatment caused a significant decrease in mean blood glucose (on week 4) and triglyceride concentrations (on weeks 3-6), significantly slowed the increase in HbA1c% (on week 6) and improved glucose tolerance 120 minutes after glucose ingestion during oral glucose tolerance test versus the STZ group. Mildronate completely protected development of STZ-induced neuropathic pain from the first administration week up to end of the experiment. The obtained data indicate clinical usefulness of the drug for the treatment of diabetes mellitus and its complications. PMID:22629599

  6. Protective effects of resveratrol against streptozotocin-induced diabetes in rats by modulation of visfatin/sirtuin-1 pathway and glucose transporters.

    PubMed

    Gencoglu, Hasan; Tuzcu, Mehmet; Hayirli, Armagan; Sahin, Kazim

    2015-05-01

    This experiment was aimed at elucidating the protective effect of resveratrol against diabetes. Forty male Wistar albino rats were allocated into four groups: the control and streptozotocin (STZ)-induced diabetes groups were treated either with placebo (1?ml/kg, i.p.) or resveratrol (20?mg/kg, i.p.) for 8 weeks. Body weight, blood glucose and serum malondialdehyde (MDA) concentrations were monitored. At the end of the experimental period, expression levels of visfatin, sirtuin-1 (SIRT1) and glucose transporters (GLUTs, 2 and 4) were measured in skeletal muscle and pancreas by Western blotting. The resveratrol treatment partially compensated for body weight loss and alleviated hyperglycaemia and returned serum MDA concentrations to the control group levels. Data suggest that supplementation may reduce the severity of diabetes and its complications through suppressing oxidative stress and increasing potential to internalise glucose by extrahepatic tissues. PMID:25666415

  7. Effect of Calendula officinalis hydroalcoholic extract on passive avoidance learning and memory in streptozotocin-induced diabetic rats

    PubMed Central

    Moradkhani, Shirin; Salehi, Iraj; Abdolmaleki, Somayeh; Komaki, Alireza

    2015-01-01

    Background: Medicinal plants, owing to their different mechanisms such as antioxidants effects, may improve learning and memory impairments in diabetic rats. Calendula officinalis (CO), has a significant antioxidant activity. Aims: To examine the effect of hydroalcoholic extract of CO on passive avoidance learning (PAL) and memory in streptozotocin (STZ)-induced diabetic male rats. Settings and Design: A total of 32 adult male Wistar rats were randomly allocated to four groups: Control, diabetic, control + extract of CO and diabetic control + extract of CO groups with free access to regular rat diet. Subjects and Methods: Diabetes in diabetic rats was induced by single intraperitoneal injection of 60 mg/kg STZ. After confirmation of diabetes, oral administration of 300 mg/kg CO extract to extract-treated groups have been done. PAL was tested 8 weeks after onset of treatment, and blood glucose and body weight were measured in all groups at the beginning and end of the experiment. Statistical Analysis Used: The statistical analysis of data was performed by ANOVA followed by least significant difference post-hoc analysis. Results: Diabetes decreased learning and memory. Effect of CO extract in retention test (after 24 and 48 h) has been shown a significant decrease in step-through latency and increase in time spent in the dark compartment part. Also the extract partially improved hyperglycemia and reduced body weight. Conclusion: Taken together, CO extract can improve PAL and memory impairments in STZ-diabetic rats. This improvement may be due to its antioxidant, anticholinergic activities or its power to reduce hyperglycemia. PMID:26120230

  8. Syzygium cumini ameliorates insulin resistance and ?-cell dysfunction via modulation of PPAR, dyslipidemia, oxidative stress, and TNF-? in type 2 diabetic rats.

    PubMed

    Sharma, Ashok Kumar; Bharti, Saurabh; Kumar, Rajiv; Krishnamurthy, Bhaskar; Bhatia, Jagriti; Kumari, Santosh; Arya, Dharamvir Singh

    2012-01-01

    Syzygium cumini (SC) is well known for its anti-diabetic potential, but the mechanism underlying its amelioration of type 2 diabetes is still elusive. Therefore, for the first time, we investigated whether SC aqueous seed extract (100, 200, or 400 mg/kg) exerts any beneficial effects on insulin resistance (IR), serum lipid profile, antioxidant status, and/or pancreatic ?-cell damage in high-fat diet / streptozotocin-induced (HFD-STZ) diabetic rats. Wistar albino rats were fed with HFD (55% of calories as fat) during the experiment to induce IR and on the 10th day were injected with STZ (40 mg/kg, i.p.) to develop type 2 diabetes. Subsequently, after confirmation of hyperglycemia on the 14th day (fasting glucose level > 13.89 mM), diabetic rats were treated with SC for the next 21 days. Diabetic rats showed increased serum glucose, insulin, IR, TNF-?, dyslipidemia, and pancreatic thiobarbituric acid-reactive substances with a concomitant decrease in ?-cell function and pancreatic superoxide dismutase, catalase, and glutathione peroxidase antioxidant enzyme activities. Microscopic examination of their pancreas revealed pathological changes in islets and ?-cells. These alterations reverted to near-normal levels after treatment with SC at 400 mg/kg. Moreover, hepatic tissue demonstrated increased PPAR? and PPAR? protein expressions. Thus, our study demonstrated the beneficial effect of SC seed extract on IR and ?-cell dysfunction in HFD-STZ-induced type 2 diabetic rats. PMID:22786584

  9. Protective effects of geraniol (a monoterpene) in a diabetic neuropathy rat model: attenuation of behavioral impairments and biochemical perturbations.

    PubMed

    Prasad, Sathya N; Muralidhara

    2014-09-01

    Involvement of oxidative stress, inflammatory response, and mitochondrial dysfunction in the development of diabetic neuropathy (DN) is well appreciated. The present study examines the potential of geraniol (GE), a well-known phytoconstituent commonly found in lemon, spices, rose oil, etc., to attenuate DN-associated oxidative/nitrosative stress by employing a streptozotocin (STZ) diabetic rat model. STZ-induced diabetic rats provided with oral supplements of GE (100 mg/kg bw/day, 8 weeks) exhibited significant improvement in tail-flick latency (sensory function) and the narrow beam test (motor function). Terminally, elevated levels of oxidative markers (reactive oxygen species, malondialdehyde, hydroperoxides) in cytosol of the sciatic nerve (SN) and in selected regions of the brain of diabetic rats were markedly reduced by GE supplements. Furthermore, GE significantly diminished the levels of protein carbonyls (a measure of protein oxidation) and nitrites in diabetic rats. In addition, in mitochondria, GE supplements restored the activities of enzymes, such as complexes I-III, succinate dehydrogenase, and citrate synthase, in brain regions of diabetic rats, with a concomitant reduction in the levels of oxidative markers. GE significantly lowered the enhanced cytosolic calcium levels and acetylcholinesterase activity in the SN and the brain regions of diabetic rats. Depleted dopamine levels evident in the SN and the cortex/striatum among diabetic rats were restored by GE. From our data, we hypothesize that GE may be a promising therapeutic candidate in the management of DN in humans. Further understanding of the molecular mechanisms of its neuromodulatory effects is essential in order to exploit its therapeutic efficacy. PMID:24752916

  10. Effect of Unripe Plantain (Musa paradisiaca) and Ginger (Zingiber officinale) on Blood Glucose, Body Weight and Feed Intake of Streptozotocin-induced Diabetic Rats

    PubMed Central

    M, Iroaganachi; C.O, Eleazu; P.N, Okafor; N, Nwaohu

    2015-01-01

    Objective: To determine the effect of unripe plantain (Musa paradisiaca) and ginger (Zingiber officinale) on blood glucose (BG), feed intake (FI) and weight of streptozotocin (STZ) induced diabetic rats. Methods: Twenty four male albino rats were used and were divided into 4 groups of 6 rats each. Group 1 (non-diabetic) and Group 2 (diabetic) received standard rat feed; Group 3 received unripe plantain incorporated feed (810 /kg body weight) and Group 4 received unripe plantain+ginger incorporated feed (710:100 g/kg body weight). The weights and FI of the rats were measured daily throughout the experimentation. Results: Groups 3 and 4 rats had 159.52% and 71.83% decreases in BG but 24.91% and 35.32% decreases in weights compared with groups 1 and 2 rats that had 2.09% and 22.94% increases in BG with 13.42% increase and 45.36% decrease in weights respectively. The FI of the experimental rats did not differ significantly from each other (P>0.05) at the end of experimentation. The standard rat feed contained higher amounts of Ca but lower amounts of Mg and Fe compared with the unripe plantain and unripe plantain+ginger incorporated feeds. Conclusion: Combination of unripe plantain and ginger at the dose used in the management of diabetes was not very effective compared with unripe plantain alone. PMID:25674161

  11. Ocular nerve growth factor administration counteracts the impairment of neural precursor cell viability and differentiation in the brain subventricular area of rats with streptozotocin-induced diabetes.

    PubMed

    Tirassa, Paola; Maccarone, Mattia; Carito, Valentina; De Nicol, Sara; Fiore, Marco

    2015-05-01

    The ocular administration of nerve growth factor (NGF) as eye drops (oNGF) has been shown to exert protective effects in forebrain-injured animal models, including adult diabetes induced by a single injection of streptozotocin (STZ) (60mg/kg body weight). This type 1 diabetes model was used in this study to investigate whether oNGF might extend its actions on neuronal precursors localised in the subventricular zone (SVZ). NGF or saline was administrated as eye drops twice daily for 2weeks in rats with STZ-induced diabetes and healthy control rats. The expression of mature and precursor NGF and the NGF receptors, tropomyosin-related kinase A and neurotrophin receptor p75, and the levels of DNA fragmentation were analysed by ELISA and western blotting. Incorporation of bromodeoxyuridine was used to trace newly formed cells. Nestin, polysialylated neuronal cell adhesion molecule (PSA-NCAM), doublecortin (DCX) and glial fibrillary acidic protein antibodies were used to identify the SVZ cells by confocal microscopy. It was found that oNGF counteracts the STZ-induced cell death and the alteration of mature/pro-NGF expression in the SVZ. It also affects the survival and differentiation of SVZ progenitors. In particular, oNGF counteracts the reduction in the number of cells expressing PSA-NCAM/DCX (neuroblast type A cells) and the related reductions in the number and distribution of nestin/DCX-positive cells (C-type cells), or glia-committed cells (type B cells), observed in the SVZ of diabetic rats. These findings show that oNGF treatment counteracts the effect of type 1 diabetes on neuronal precursors in the SVZ, and further support the neuroprotective and reparative role of oNGF in the brain. PMID:25728260

  12. Enhancement of Antihyperalgesia by the Coadministration of N-palmitoylethanolamide and Acetaminophen in Diabetic Rats.

    PubMed

    Dciga-Campos, Myrna; Ortz-Andrade, Rolffy

    2015-08-01

    Preclinical Research The objective of this study was to evaluate the pharmacological antihyperalgesic interaction between N-palmitoylethanolamide (PEA) and acetaminophen in diabetic rats using the formalin paw test. Streptozotocin (STZ)-induced diabetic rats received subcutaneous injections in the paw of PEA alone (1-100 ?g/paw) or acetaminophen alone (3-300 ?g/paw) 15 min before formalin (0.5%) injection. The results revealed concentration-dependent responses produced by PEA (EC50 = 7.19 0.7 ?g/paw) and acetaminophen (EC50 = 57.9 1.9 ?g/paw). Isobolographic analysis was used to evaluate the pharmacological interaction between the PEA + acetaminophen using the EC50 value and a fixed 1:1 ratio combination. The isobologram demonstrated that the combination investigated in this study produced a synergistic interaction; the experimental value (EC50 = 23.64 1.9 ?g/paw) was significantly smaller than those that resulted from theoretical calculations (EC50 = 32.56 ?g/paw). These results provide evidence that PEA in combination with acetaminophen could be useful for pain therapy in neuropathic diabetic patients. PMID:26218800

  13. Effects of lichen extracts on haematological parameters of rats with experimental insulin-dependent diabetes mellitus.

    PubMed

    Colak, Suat; Geyikoğlu, Fatime; Aslan, Ali; Deniz, Gülşah Yıldız

    2014-11-01

    The prevalence of diabetes mellitus in the world is steadily increasing. Oxidative stress contributes to the development of diabetic complications, including diabetic haematological changes. Lichens are used as food supplements and are also used as possible natural antioxidant, antimicrobial and anticancer agents. We hypothesized that antioxidant activity of lichens may decrease hyperglycaemia-induced oxidative stress and prevent the development of diabetic complications, including abnormality in haematological condition. Therefore, the effects of Cetraria islandica water extract (CIWE) and Pseudevernia furfuracea water extract (PFWE) on the haematological parameters of rats with type 1 DM were investigated for the first time in the present study. Control Sprague-Dawley or streptozotocin (STZ)-induced diabetic rats were either untreated or treated with water lichen extracts (5-500 mg/kg body weight (bw)/day) for 2 weeks, starting at 72 h after STZ injection. On day 14, animals were anaesthetized and haematological and metabolic parameters were determined between control and experimental groups. In addition, the total oxidative stress (TOS), a specific indicator of oxidative stress, and the total antioxidant capacity (TAC) were measured by biochemical studies. In diabetic rats, CIWE of 250-500 mg/kg bw dose showed more prominent results when compared with doses of PFWE for TAC. The results obtained in the present study suggested that the antioxidant activities of lichens might be the possible reason behind the observed antihaematological status. However, the protective effect of lichen extracts were inadequate on diabetes-induced microcytic hypochromic anaemia. In addition, the extracts have no effect on metabolic complications. Our experimental data showed that high doses of CIWE and PFWE alone have no detrimental effect on blood cells and TOS status of plasma. Hence, they are safe and suitable for different administration routes. PMID:23114377

  14. Effect of Lactobacillus casei on the Production of Pro-Inflammatory Markers in Streptozotocin-Induced Diabetic Rats.

    PubMed

    Zarfeshani, A; Khaza'ai, H; Mohd Ali, R; Hambali, Z; Wahle, K W J; Mutalib, M S A

    2011-12-01

    It has been demonstrated that probiotic supplementation has positive effects in several murine models of disease through influences on host immune responses. This study examined the effect of Lactobacillus casei strain Shirota (L. casei Shirota) on the blood glucose, C-reactive protein (CRP), Interleukin-6 (IL-6), Interleukin-4 (IL-4), and body weight among STZ-induced diabetic rats. Diabetes mellitus was induced by streptozotocin (STZ, 50mg/kg BW) in male Sprague-Dawley rats. Streptozotocin caused a significant increase in the blood glucose levels, CRP, and IL-6. L. casei Shirota supplementation lowered the CRP and IL-6 levels but had no significant effect on the blood glucose levels, body weight, or IL-4. Inflammation was determined histologically. The presence of the innate immune cells was not detectable in the liver of L. casei Shirota-treated hyperglycemic rats. The probiotic L. casei Shirota significantly lowered blood levels of pro-inflammatory cytokines (IL-6, CRP) and neutrophils in diabetic rats, showing a lower risk of diabetes mellitus and its complications. PMID:26781677

  15. Ameliorative effects of pentoxifylline on NOS induced by diabetes in rat kidney.

    PubMed

    Sönmez, Mehmet Fatih; Dündar, Munis

    2016-05-01

    Objectives Diabetic nephropathy (DN) is the leading cause of end-stage renal disease worldwide. The NO system has been implicated in the pathogenesis of DN. In this study, we aimed to evaluate the healing effect of pentoxifylline on NOS in STZ-induced diabetic rat's kidney. Material and methods In this study, 50 Wistar albino male rats were used. The rats were divided into five groups; Group C control; Group D only diabetes; Group D + PI and D + PII diabetes + pentoxifylline; Group P only pentoxifylline. Group DPI rats received just pentoxifylline from the beginning of the experiments. However, Group DPII rats received saline in the first month and 50 mg/kg/day of pentoxifylline for the following month. At the end of two months, NOS expressions in kidney tissue were assessed using qRT-PCR and immunohistochemistry analysis. Results At the end of the experiments, desquamation of the epithelial cells of the tubules, clear glycogen-filled distal tubules and increased number of apoptotic cells were seen in Group D. Diabetic rats' nNOS immunoreactivity had increased and eNOS and iNOS immunoreactivity had decreased; nNOS, iNOS and eNOS mRNA levels tended to decrease compared to the control group. PTX ameliorated eNOS, iNOS and nNOS protein levels and apoptotic cells, but did not affect mRNA levels. Conclusion In conclusion, PTX has a healing effect on this damage by affecting NOS expression. PMID:26905686

  16. Insulinotropic effect of cinnamaldehyde on transcriptional regulation of pyruvate kinase, phosphoenolpyruvate carboxykinase, and GLUT4 translocation in experimental diabetic rats.

    PubMed

    Anand, Prachi; Murali, K Y; Tandon, Vibha; Murthy, P S; Chandra, Ramesh

    2010-06-01

    Diabetes mellitus is a chronic metabolic disorder affecting about 6% of population worldwide with its complications and is rapidly reaching epidemic scale. Cinnamomum zeylanicum is widely used in alternative system of medicine for treatment of diabetes. In the present study, we have performed bioassay guided fractionation of chloroform extract of C. zeylaniucm and identified cinnamaldehyde (CND) as an active principle against diabetes. In continuation to it, a detailed study was undertaken to elucidate its mode of antidiabetic action in STZ induced diabetic rats. Oral administration of CND (20 mg/kg bw) to diabetic rats for 2 months showed significant improvement (p<0.001) in muscle and hepatic glycogen content. In vitro incubation of pancreatic islets with CND enhanced the insulin release compared to glibenclamide. The insulinotropic effect of CND was found to increase the glucose uptake through glucose transporter (GLUT4) translocation in peripheral tissues. The treatment also showed a significant improvement in altered enzyme activities of pyruvate kinase (PK) and phosphoenolpyruvate carboxykinase (PEPCK) and their mRNA expression levels. Furthermore, the median lethal dose (LD(50)) of CND could not be obtained even at 20 times (0.4 g/kg bw) of its effective dose. With the high margin of safety of CND, it can be developed as a potential therapeutic candidate for the treatment of diabetes. PMID:20363216

  17. A local renal renin–angiotensin system activation via renal uptake of prorenin and angiotensinogen in diabetic rats

    PubMed Central

    Tojo, Akihiro; Kinugasa, Satoshi; Fujita, Toshiro; Wilcox, Christopher S

    2016-01-01

    The mechanism of activation of local renal renin–angiotensin system (RAS) has not been clarified in diabetes mellitus (DM). We hypothesized that the local renal RAS will be activated via increased glomerular filtration and tubular uptake of prorenin and angiotensinogen in diabetic kidney with microalbuminuria. Streptozotocin (STZ)-induced DM and control rats were injected with human prorenin and subsequently with human angiotensinogen. Human prorenin uptake was increased in podocytes, proximal tubules, macula densa, and cortical collecting ducts of DM rats where prorenin receptor (PRR) was expressed. Co-immunoprecipitation of kidney homogenates in DM rats revealed binding of human prorenin to the PRR and to megalin. The renal uptake of human angiotensinogen was increased in DM rats at the same nephron sites as prorenin. Angiotensin-converting enzyme was increased in podocytes, but decreased in the proximal tubules in DM rats, which may have contributed to unchanged renal levels of angiotensin despite increased angiotensinogen. The systolic blood pressure increased more after the injection of 20 μg of angiotensinogen in DM rats than in controls, accompanied by an increased uptake of human angiotensinogen in the vascular endothelium. In conclusion, endocytic uptake of prorenin and angiotensinogen in the kidney and vasculature in DM rats was contributed to increased tissue RAS and their pressor response to angiotensinogen. PMID:26848273

  18. A local renal renin-angiotensin system activation via renal uptake of prorenin and angiotensinogen in diabetic rats.

    PubMed

    Tojo, Akihiro; Kinugasa, Satoshi; Fujita, Toshiro; Wilcox, Christopher S

    2016-01-01

    The mechanism of activation of local renal renin-angiotensin system (RAS) has not been clarified in diabetes mellitus (DM). We hypothesized that the local renal RAS will be activated via increased glomerular filtration and tubular uptake of prorenin and angiotensinogen in diabetic kidney with microalbuminuria. Streptozotocin (STZ)-induced DM and control rats were injected with human prorenin and subsequently with human angiotensinogen. Human prorenin uptake was increased in podocytes, proximal tubules, macula densa, and cortical collecting ducts of DM rats where prorenin receptor (PRR) was expressed. Co-immunoprecipitation of kidney homogenates in DM rats revealed binding of human prorenin to the PRR and to megalin. The renal uptake of human angiotensinogen was increased in DM rats at the same nephron sites as prorenin. Angiotensin-converting enzyme was increased in podocytes, but decreased in the proximal tubules in DM rats, which may have contributed to unchanged renal levels of angiotensin despite increased angiotensinogen. The systolic blood pressure increased more after the injection of 20 ?g of angiotensinogen in DM rats than in controls, accompanied by an increased uptake of human angiotensinogen in the vascular endothelium. In conclusion, endocytic uptake of prorenin and angiotensinogen in the kidney and vasculature in DM rats was contributed to increased tissue RAS and their pressor response to angiotensinogen. PMID:26848273

  19. Hypolipidemic and hypoglycemic effects of Orostachys japonicus A. Berger extracts in streptozotocin-induced diabetic rats

    PubMed Central

    Lee, Soo Jung; Zhang, Gui Fang

    2011-01-01

    The hypolipidemic and hypoglycemic effects of two dietary dosages (0.1% and 0.5%) of water and 80% ethanol extracts from hot-air dried Orostachys japonicus A. Berger were evaluated in the serum and organ tissues of streptozotocin-induced diabetic rats. The STZ-induced diabetic groups supplemented with the O. japonicus extracts showed significantly higher body weight compared to a diabetic control group at the end of experiment. The extracts exhibited substantial hypoglycemic effects by significant reductions of fasting blood glucose levels at all time points tested compared to the initial stage before treatment of the extracts. Declines of serum and hepatic triglyceride levels were greater than declines of total cholesterol in the groups treated with the 0.5% O. japonicus extract (DBW2 and DBE2) when compared to the DBC group. Hepatic glycogen content was higher in the groups treated with O. japonicus extract, while lipid peroxide content was decreased in these treated groups compared to the DBC group. Hepatic antioxidant activity was significantly increased in the groups supplemented with the O. japonicus ethanol extract. The hypolipidemic and hypoglycemic effects of the O. japonicus ethanol extract were significantly greater than the effects of the water extract. Based on this study, it seems that O. japonicus ethanol extract, due to its higher phenolic and flavonoid components than the water extract, may control blood glucose and alleviate hyperlipidemia in diabetes. PMID:21994524

  20. Sequential alterations of glucocorticoid receptors in the hippocampus of STZ-treated type 1 diabetic rats

    PubMed Central

    Shin, Jae Hoon; Seong, Je Kyung

    2014-01-01

    Type 1 diabetes is a common metabolic disorder accompanied by increased blood glucose levels along with glucocorticoid and cognitive deficits. The disease is also thought to be associated with environmental changes in brain and constantly induces oxidative stress in patients. Therefore, glucocorticoid-mediated negative feedback mechanisms involving the glucocorticoid receptor (GR) binding site are very important to understand the development of this disease. Many researchers have used streptozotocin (STZ)-treated diabetic animals to study changes in GR expression in the brain. However, few scientists have evaluated the hyperglycemic period following STZ exposure. In the present study, we found GR expression in the hippocampus varied based on the period after STZ administration for up to 4 weeks. We performed immunohistochemistry and Western blotting to validate the sequential alterations of GR expression in the hippocampus of STZ-treated type 1 diabetic rats. GR protein expression increased significantly until week 3 but decreased at week 4 following STZ administration. GR expression after 70 mg/kg STZ administration was highest at 3 weeks post-treatment and decreased thereafter. Although STZ-induced increase in GR expression in diabetic animals has been described, our data indicate that researchers should consider the sequential GR expression changes during the hyperglycemic period following STZ exposure. PMID:23820217

  1. Protective effect of Psidium guajava leaf extract on altered carbohydrate metabolism in streptozotocin-induced diabetic rats.

    PubMed

    Khan, Haseena Banu Hedayathullah; Shanmugavalli, R; Rajendran, Deepa; Bai, Mookambikai Ramya; Sorimuthu, Subramanian

    2013-12-01

    Psidium guajava is an important plant of high medicinal value and has been used in traditional systems of medicine against various ailments. The antidiabetic effect of the ethanolic extract of Psidium guajava leaves and also its protective effect on altered glucose metabolism was evaluated in streptozotocin (stz)-induced diabetic rat model. Diabetes was induced in rats by means of intraperitoneal injection of 50-mg/kg body weight (b.wt.) of stz. Diabetes-induced rats were randomly divided into two groups. One group of rats was treated with Psidium guajava leaf extract at a dosage of 300-mg/kg b.wt. and the other group of rats was treated with the standard drug glyclazide at a dosage of 5-mg/kg b.wt. for 30 days. The blood glucose levels, plasma insulin, Hb, HbA1c were measured. The effect on the drug on altered glucose metabolizing enzymes were also studied. Treatment with Psidium guajava extract showed a significant reduction in blood glucose and HbA1c levels and a significant increase in plasma insulin levels. The drug also significantly restored the activities of carbohydrate metabolizing enzymes. This suggests that the potential antidiabetic effect of the ethanolic extract of the Psidium guajava leaves may be due to the presence of flavonoids and other phenolic components present in the drug. PMID:24237189

  2. Effects of Momordica charantia on pancreatic histopathological changes associated with streptozotocin-induced diabetes in neonatal rats.

    PubMed

    Abdollahi, M; Zuki, A B Z; Goh, Y M; Rezaeizadeh, A; Noordin, M M

    2011-01-01

    The aim of this research was to determine the effects of Momordica charantia (MC) fruit aqueous extract on pancreatic histopathological changes in neonatal STZ-induced type-II diabetic rats. Diabetes mellitus was induced in one day Sprague-Dawley neonatal rats using a single intrapretoneal injection of streptozotocin (STZ) (85 mg/kg body weight) and monitored for 12 weeks thereafter. The diabetic rats were separated into three groups, as follows: the diabetic control group (i.e. nSTZ), the diabetic group (i.e. nSTZ/M) - which was orally given 20 mg/kg of MC fruit extract, and the diabetic group (i.e. nSTZ/G) - that was treated with glibenclamide, 0.1 mg/kg for a period of four weeks. At the end of treatment, the animals were sacrificed and blood samples were collected from the saphenous vein to measure the blood glucose and serum insulin level. The pancreatic specimens were removed and processed for light microscopy, electron microscopy examination and immunohistochemical study. The results of this study showed that MC fruit aqueous extract reduced the blood glucose level as well as glibenclamide and increased the serum insulin level in the treated diabetic rats (P<0.05). The fruit extract of MC alleviated pancreatic damage and increased the number of ?-cells in the diabetic treated rats (P<0.05). Our results suggest that oral feeding of MC fruit extract may have a significant role in the renewal of pancreatic ?-cells in the nSTZ rats. PMID:21117023

  3. In Vivo Assessment of Antihyperglycemic and Antioxidant Activity from Oil of Seeds of Brassica Nigra in Streptozotocin Induced Diabetic Rats

    PubMed Central

    Kumar, Manoj; Sharma, Sunil; Vasudeva, Neeru

    2013-01-01

    Purpose: This study was made to investigate the antihyperglycemic and antioxidant potential of oil of seeds of Brassica nigra (BNO) in streptozotocin -nicotinamide (STZ) induced type 2 diabetic rats. Methods: BNO was orally administered to diabetic rats to study its effect in both acute and chronic antihyperglycemic study. The body weight, oral glucose tolerance test and biochemical parameters viz. glucose level, insulin level, liver glycogen content, glycosylated hemoglobin and antioxidant parameters were estimated for all treated groups and compared against diabetic control group. Results: Administration of BNO at a dose 500 mg/kg and 1000 mg/kg body weight p.o. to STZ diabetic rats showed reduction in blood glucose level from 335 mg/dl to 280 mg/dl at 4th h and from 330 mg/dl to 265 mg/dl respectively which was found significant (p<0.01) as compared with diabetic control. BNO (500 mg/kg and 1000 mg/kg) and glibenclamide (0.6 mg/kg) in respective groups of diabetic animals administered for 28 days reduced the blood glucose level in streptozotocin-nicotinamide induced diabetic rats. There was significant increase in body weight, liver glycogen content, plasma insulin level and decrease in glycosylated hemoglobin in test groups as compared to control group. In vivo antioxidant studies on STZ-nicotinamide induced diabetic rats revealed decreased malondialdehyde (MDA) and increased reduced glutathione (GSH). Conclusion: Thus the results showed that the oil of seeds of Brassica nigra has significant antihyperglycemic and antioxidant activity. PMID:24312861

  4. Transdermal Delivery of Insulin by Amidated Pectin Hydrogel Matrix Patch in Streptozotocin-Induced Diabetic Rats: Effects on Some Selected Metabolic Parameters

    PubMed Central

    Hadebe, Silindile I.; Ngubane, Phikelelani S.; Serumula, Metse R.; Musabayane, Cephas T.

    2014-01-01

    Purpose Studies in our laboratory are concerned with developing optional insulin delivery routes based on amidated pectin hydrogel matrix gel. We therefore investigated whether the application of pectin insulin (PI)-containing dermal patches of different insulin concentrations sustain controlled release of insulin into the bloodstream of streptozotocin (STZ)-induced diabetic rats with concomitant alleviation of diabetic symptoms in target tissues, most importantly, muscle and liver. Methods Oral glucose test (OGT) responses to PI dermal matrix patches (2.47, 3.99, 9.57, 16.80 µg/kg) prepared by dissolving pectin/insulin in deionised water and solidified with CaCl2 were monitored in diabetic rats given a glucose load after an 18-h fast. Short-term (5 weeks) metabolic effects were assessed in animals treated thrice daily with PI patches 8 hours apart. Animals treated with drug-free pectin and insulin (175 µg/kg, sc) acted as untreated and treated positive controls, respectively. Blood, muscle and liver samples were collected for measurements of selected biochemical parameters. Results After 5 weeks, untreated diabetic rats exhibited hyperglycaemia and depleted hepatic and muscle glycogen concentrations. Compared to untreated STZ-induced diabetic animals, OGT responses of diabetic rats transdermally applied PI patches exhibited lower blood glucose levels whilst short-term treatments restored hepatic and muscle glycogen concentrations. Plasma insulin concentrations of untreated diabetic rats were low compared with control non-diabetic rats. All PI treatments elevated plasma insulin concentrations of diabetic rats although the levels induced by high doses (9.57 and 16.80 µg/kg) were greater than those caused by low doses (2.47 and 3.99 µg/kg) but comparable to those in sc insulin treated animals. Conclusions The data suggest that the PI hydrogel matrix patch can deliver physiologically relevant amounts of pharmacologically active insulin. Novelty of the Work A new method to administer insulin into the bloodstream via a skin patch which could have potential future applications in diabetes management is reported. PMID:24987850

  5. Voltage-dependence of contraction in streptozotocin-induced diabetic myocytes.

    PubMed

    Bracken, N K; Woodall, A J; Howarth, F C; Singh, J

    2004-06-01

    Cardiac contractile dysfunction is frequently reported in human patients and experimental animals with type-1 diabetes mellitus. The aim of this study was to investigate the voltage-dependence of contraction in ventricular myocytes from the streptozotocin (STZ)-induced diabetic rat. STZ-induced diabetes was characterised by hyperglycaemia and hypoinsulinaemia. Other characteristics included reduced body and heart weight and raised blood osmolarity. Isolated ventricular myocytes were patched in whole cell, voltage-clamp mode after correcting for membrane capacitance and series resistance. From a holding membrane potential of -40 mV, test pulses were applied at potentials between -30 and +50 mV in 10 mV increments. L-type Ca2+ current (I Ca,L) density and contraction were measured simultaneously using a video-edge detection system. Membrane capacitance was not significantly altered between control and STZ-induced diabetic myocytes. The I Ca,L density was significantly (p < 0.05) reduced throughout voltage ranges (-10 mV to +10 mV) in myocytes from STZ-treated rats compared to age-matched controls. Moreover, the amplitude of contraction was significantly reduced (p < 0.05) in myocytes from STZ-treated rats at all test potentials between -20 mV and +30 mV. However, in electrically field-stimulated (1 Hz) myocytes, the amplitude of contraction was not altered by STZ-treatment. It is suggested that in field-stimulated myocytes taken from STZ-induced diabetic hearts, prolonged action potential duration may promote increased Ca2+ influx via the sodium-calcium exchanger (NCX), which may compensate for a reduction in Ca2+ trigger through L-type-Ca2+-channels and lead to normalised contraction. PMID:15362509

  6. Improvement of biochemical parameters in type 1 diabetic rats after the roots aqueous extract of yacon [Smallanthus sonchifolius (Poepp.& Endl.)] treatment.

    PubMed

    Oliveira, Gilberto Ornelas; Braga, Camila Pereira; Fernandes, Ana Anglica Henrique

    2013-09-01

    The aim of this study was to evaluate the effect of yacon (Smallanthus sonchifolius) (Poepp.& Endl.) on clinical parameters under diabetic conditions. The aqueous extract of yacon tuberous roots (YRAE; 0.76 g fructan kg? body weight) was prepared at the moment of each administration. Thirty-two male rats were divided into four groups (n=8): control group (C); group that received YRAE (Y); untreated diabetic group (DM1); and diabetic group treated with YRAE (Y-DM1). The diabetes mellitus was induced by streptozotocin (60 mg kg? body weight). The animals from Y2 and Y-DM1 received YRAE by gavage, at 7-day intervals, for 30 days. The aqueous extract of yacon roots decreased (p<0.05) the water and food intake in diabetic rats (Y-DM1). YRAE treatment reduced (p<0.05) glycaemia, total cholesterol, VLDL-c, LDL-c and triacylglycerol levels in diabetic rats (YRAE). HDL, urea and creatinine levels did not differ (p>0.05) between the Y and Y-DM1 groups. YRAE normalised alanine aminotransferase (ALT) activity, when comparing DM1 and Y-DM1 rats, but had no effect on lactate dehydrogenase activity (LDH). In conclusion, YRAE was sufficient for controlling water and food consumption, hyperglycaemia and dyslipidaemia, and promote the reduction of the ALT, suggesting a hepatoprotective effect in rats with STZ-induced DM1. PMID:23770327

  7. Evaluation of Neonatal Streptozotocin Induced Diabetic Rat Model for the Development of Cataract

    PubMed Central

    Patil, Madhoosudan A.; Suryanarayana, Palla; Putcha, Uday Kumar; Srinivas, Myadara

    2014-01-01

    Type 2 diabetes (T2D) generally follows prediabetes (PD) conditions such as impaired fasting glucose (IFG) and/or impaired glucose tolerance (IGT). Although studies reported an association of IGT or IFG with cataract, the experimental basis for PD associated cataract is not known. Hence, we evaluated neonatal streptozotocin (nSTZ) induced rat model to study PD associated cataractogenesis by injecting STZ to two-day old rats. While majority (70%) of nSTZ injected pups developed IGT (nSTZ-PD) by two months but not cataract even after seven months, remaining (30%) nSTZ rats developed hyperglycemia (nSTZ-D) by two months and mature cataract by seven months. Lens biochemical analysis indicated increased oxidative stress as indicated by increased SOD activity, lipid peroxidation, and protein carbonyl levels in nSTZ-D cataractous lens. There was also increased polyol pathway as assessed by aldose reductase activity and sorbitol levels. Though nSTZ-PD animals have not shown any signs of lenticular opacity, insolubilization of proteins along with enhanced polyol pathway was observed in the lens. Further there was increased oxidative stress in lens of IGT animals. These results suggest that oxidative stress along with increased polyol pathway might play a role in IGT-associated lens abnormalities. In conclusion, nSTZ-PD rat model could aid to investigate IGT-associated lens abnormalities. PMID:25505935

  8. Mechanism Investigation of the Improvement of Chang Run Tong on the Colonic Remodeling in Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Sha, Hong; Zhao, Dong; Tong, Xiaolin; Zhao, Jingbo

    2016-01-01

    Previous study demonstrated that Chang Run Tong (CRT) could partly restore the colon remodeling in streptozotocin- (STZ-) induced diabetic rats. Here we investigated the mechanisms of such effects of CRT. Diabetes was induced by a single injection of 40 mg/kg of STZ. CRT was poured into the stomach by gastric lavage once daily for 60 days. The remodeling parameters were obtained from diabetic (DM), CRT treated diabetic (T1, 50 g/kg; T2, 25 g/kg), and normal (Con) rats. Expressions of advanced glycation end product (AGE), AGE receptor, transforming growth factor-β1 (TGF-β1), and TGF-β1 receptor in the colon wall were immunochemically detected and quantitatively analyzed. The association between the expressions of those proteins and the remodeling parameters was analyzed. The expressions of those proteins were significantly higher in different colon layers in the DM group (P < 0.05, P < 0.01) and highly correlated to the remodeling parameters. Furthermore, the expressions of those proteins were significantly decreased in the T1 group (P < 0.05, P < 0.01) but not in the T2 group (P > 0.05). The corrective effect on the expressions of those proteins is likely to be one molecular pathway for the improvement of CRT on the diabetes-induced colon remodeling. PMID:26839890

  9. Mechanism Investigation of the Improvement of Chang Run Tong on the Colonic Remodeling in Streptozotocin-Induced Diabetic Rats.

    PubMed

    Sha, Hong; Zhao, Dong; Tong, Xiaolin; Gregersen, Hans; Zhao, Jingbo

    2016-01-01

    Previous study demonstrated that Chang Run Tong (CRT) could partly restore the colon remodeling in streptozotocin- (STZ-) induced diabetic rats. Here we investigated the mechanisms of such effects of CRT. Diabetes was induced by a single injection of 40 mg/kg of STZ. CRT was poured into the stomach by gastric lavage once daily for 60 days. The remodeling parameters were obtained from diabetic (DM), CRT treated diabetic (T1, 50 g/kg; T2, 25 g/kg), and normal (Con) rats. Expressions of advanced glycation end product (AGE), AGE receptor, transforming growth factor-β1 (TGF-β1), and TGF-β1 receptor in the colon wall were immunochemically detected and quantitatively analyzed. The association between the expressions of those proteins and the remodeling parameters was analyzed. The expressions of those proteins were significantly higher in different colon layers in the DM group (P < 0.05, P < 0.01) and highly correlated to the remodeling parameters. Furthermore, the expressions of those proteins were significantly decreased in the T1 group (P < 0.05, P < 0.01) but not in the T2 group (P > 0.05). The corrective effect on the expressions of those proteins is likely to be one molecular pathway for the improvement of CRT on the diabetes-induced colon remodeling. PMID:26839890

  10. Therapeutic effects of globular adiponectin in diabetic rats with nonalcoholic fatty liver disease

    PubMed Central

    Ma, Hong; Cui, Fan; Dong, Jing-Jing; You, Guo-Ping; Yang, Xiang-Jiu; Lu, Hua-Dong; Huang, Yan-Ling

    2014-01-01

    AIM: To explore the therapeutic role of globular adiponectin (gAd) in high-fat diet/streptozotocin (STZ)-induced type 2 diabetic rats with nonalcoholic fatty liver disease (NAFLD). METHODS: Seven rats were fed a basic diet (normal control group; NC) during the experiment. Experimental rats (14 rats) were given a high-fat diet for 4 wk and were then injected with STZ to induce type 2 diabetes mellitus (T2DM) and NAFLD. Half of the T2DM/NAFLD rats were randomly injected intraperitoneally with gAd for 7 d (gAd-treated group), while the other 7 rats (T2DM/NAFLD group) received 0.9% saline. Plasma biochemical parameters and insulin concentrations were measured. Liver histopathology was examined by hematoxylin-eosin staining. Insulin receptor expression in the liver was analyzed by immunohistochemical staining, Western blot and quantitative real-time reverse transcription polymerase chain reaction analysis. RESULTS: Compared to the control group, the T2DM/NAFLD group had increased levels of glucolipid and decreased levels of insulin. Plasma glucose and lipid levels were decreased in the gAd-treated group, while serum insulin levels increased. The expression of insulin receptor in the T2DM/NAFLD group increased compared with the NC group, and gAd downregulated insulin receptor expression in the livers of T2DM/NAFLD rats. Steatosis of the liver was alleviated in the gAd-treated group compared to the T2DM/NAFLD group (NAS 1.39 0.51 vs 1.92 0.51, P < 0.05). CONCLUSION: Globular adiponectin exerts beneficial effects in T2DM rats with NAFLD by promoting insulin secretion, mediating glucolipid metabolism, regulating insulin receptor expression and alleviating hepatic steatosis. PMID:25356056

  11. Non-obese diabetic mice rapidly develop dramatic sympathetic neuritic dystrophy: a new experimental model of diabetic autonomic neuropathy.

    PubMed

    Schmidt, Robert E; Dorsey, Denise A; Beaudet, Lucie N; Frederick, Kathy E; Parvin, Curtis A; Plurad, Santiago B; Levisetti, Matteo G

    2003-11-01

    To address the pathogenesis of diabetic autonomic neuropathy, we have examined the sympathetic nervous system in non-obese diabetic (NOD) and streptozotocin (STZ)-induced diabetic mice, two models of type 1 diabetes, and the db/db mouse, a model of type 2 diabetes. After only 3 to 5 weeks of diabetes, NOD mice developed markedly swollen axons and dendrites ("neuritic dystrophy") in the prevertebral superior mesenteric and celiac ganglia (SMG-CG), similar to the pathology described in diabetic STZ- and BBW-rat and man. Comparable changes failed to develop in the superior cervical ganglia of the NOD mouse or in the SMG-CG of non-diabetic NOD siblings. STZ-induced diabetic mice develop identical changes, although at a much slower pace and to a lesser degree than NOD mice. NOD-SCID mice, which are genetically identical to NOD mice except for the absence of T and B cells, do not develop diabetes or neuropathology comparable to diabetic NOD mice. However, STZ-treated NOD-SCID mice develop severe neuritic dystrophy, evidence against an exclusively autoimmune pathogenesis for autonomic neuropathy in this model. Chronically diabetic type 2 db/db mice fail to develop neuritic dystrophy, suggesting that hyperglycemia alone may not be the critical and sufficient element. The NOD mouse appears to be a valuable model of diabetic sympathetic autonomic neuropathy with unambiguous, rapidly developing neuropathology which corresponds closely to the characteristic pathology of other rodent models and man. PMID:14578206

  12. Antioxidant icariside II combined with insulin restores erectile function in streptozotocin-induced type 1 diabetic rats

    PubMed Central

    Wang, Lin; Xu, Yongde; Li, Huixi; Lei, Hongen; Guan, Ruili; Gao, Zhezhu; Xin, Zhongcheng

    2015-01-01

    Erectile dysfunction (ED) worsens in patients with diabetes mellitus (DM) despite good control of blood glucose level with insulin. Recent studies imply that diabetic vascular stresses (e.g. oxidative stress) persist in spite of glucose normalization, which is defined as metabolic memory. Studies suggest that the interaction between advanced glycation end products (AGEs) and their receptor (RAGE) mediates the development of metabolic memory. To investigate the effects of the antioxidant icariside II plus insulin on erectile function in streptozotocin (STZ)- induced type 1 diabetic rats. Fifty 8-week-old Sprague-Dawley rats were randomly distributed into five groups: normal control, diabetic, insulin-treated diabetic, icariside II-treated diabetic, and insulin plus icariside II-treated diabetic. Diabetes was induced by a single intraperitoneal injection of STZ. Eight weeks after induction of diabetes, icariside II was administered by gastric lavage once a day (5mg/kg) for 6weeks; and 26 units of intermediate-acting insulin were given to maintain normal glycemia for 6weeks. The main outcome measures were the ratio of intracavernous pressure (ICP) to mean arterial pressure (MAP); histology of penile endothelial cells and smooth muscle cells; neural nitric oxide synthase, AGEs and RAGE expression; malondialdehyde concentration; superoxide dismutase activity; and apoptosis index. Diabetic rats demonstrated a significantly lower ICP/MAP ratio, reduced penile endothelial cells, reduced smooth muscle cells, increased AGEs and RAGE, and increased apoptosis. Insulin and icariside II monotherapy partially restored erectile function and histological changes. However, the combination therapy group showed significantly better erectile parameters, cytological components and biochemistry, similar to those in the normal control group. These results suggest that, although insulin can effectively control glycemic levels, it does not completely alter the pathological changes in erectile tissues. Better efficacy could be expected with tight glycemic control plus the antioxidant icariside II. The proposed combination therapy might have the potential to eliminate metabolic memory by down-regulating the AGEs-RAGE-oxidative stress axis. PMID:25781208

  13. Gallic acid ameliorates renal functions by inhibiting the activation of p38 MAPK in experimentally induced type 2 diabetic rats and cultured rat proximal tubular epithelial cells.

    PubMed

    Ahad, Amjid; Ahsan, Haseeb; Mujeeb, Mohd; Siddiqui, Waseem Ahmad

    2015-10-01

    Diabetic nephropathy (DN) is one of the leading causes of morbidity and mortality in diabetic patients that accounts for about 40% of deaths in type 2 diabetes. p38 mitogen activated protein kinase (p38 MAPK), a serine-threonine kinase, plays an important role in tissue inflammation and is known to be activated under conditions of oxidative stress and hyperglycemia. The role of p38 MAPK has been demonstrated in DN, and its inhibition has been suggested as an alternative approach in the treatment of DN. In the present study, we investigated the nephroprotective effects of an anti-inflammatory phenolic compound, gallic acid (GA, 3,4,5-trihydroxybenzoic acid), in high fat diet/streptozotocin (HFD/STZ) induce type 2 diabetic wistar albino rats. GA (25mg/kgbw and 50mg/kgbw, p.o.) treatment for 16 weeks post induction of diabetes led to a significant reduction in the levels of blood glucose, HbA1c, serum creatinine, blood urea nitrogen and proteinuria as well as a significant reduction in the levels of creatinine clearance. GA significantly inhibited the renal p38 MAPK and nuclear factor kappa B (N-?B) activation as well as significantly reduced the levels of renal transforming growth factor beta (TGF-?) and fibronectin. Treatment with GA resulted in a significant reduction in the serum levels of proinflammatory cytokines viz. interleukin 1 beta (IL-1?), IL-6 and tumor necrosis factor alpha (TNF-?). Moreover, GA significantly lowered renal pathology and attenuated renal oxidative stress. In cultured rat NRK 52E proximal tubular epithelial cells, GA treatment inhibited high glucose induced activation of p38 MAPK and NF-?B as well as suppressed proinflammatory cytokine synthesis. The results of the present study provide invivo and invitro evidences that the p38 MAPK pathway plays an important role in the pathogenesis of DN, and GA attenuates the p38 MAPK-mediated renal dysfunction in HFD/STZ induced type 2 diabetic rats. PMID:26341651

  14. The Effect of the Medicinal Mushrooms Agaricus brasiliensis and Ganoderma lucidum (Higher Basidiomycetes) on the Erythron System in Normal and Streptozotocin-Induced Diabetic Rats.

    PubMed

    Vitak, Taras Y; Wasser, Solomon P; Nevo, Eviatar; Sybirna, Nataliya O

    2015-01-01

    Diabetes mellitus (DM) is accompanied by the development of hypoxia, which disturbs the physicochemical properties of the erythrocyte membrane and further leads to the occurrence of anemia and a reduction of the lifespan. In response, the body activates compensatory reactions directed at a renewal of the red blood cell pool and an increase in tissue oxygenation. In this study the influence of Agaricus brasiliensis and Ganoderma lucidum medicinal mushroom mycelia on the erythron system of control and streptozotocin (STZ)-induced diabetic rats were investigated. Wistar outbred white male rats were intraperitoneally injected with saline (control rats) or STZ (50 mg/kg, DM rats) and orally treated with placebo or submerged culture mycelium powder (1 g/kg/day) for 2 weeks. Peripheral blood erythrocytes were collected. Hypoglycemic effects of A. brasiliensis and G. lucidum occurred in the diabetic rats, as evidenced by decreased blood glucose and glycosylated hemoglobin concentrations. In STZ-diabetic animals treated with submerged culture mycelium powder, an increase in the number of erythrocytes in the bloodstream (an antianemic effect), erythrocyte resistance to acid hemolysis, and the normalization of fetal hemoglobin concentrations, along with the intensification of erythropoiesis were observed. In conclusion, our results suggest that in diabetic animals A. brasiliensis and G. lucidum have therapeutic effects that manifest in hypoglycemic and antianemic action. PMID:25954911

  15. Melatonin and L-carnitin improves endothelial disfunction and oxidative stress in Type 2 diabetic rats

    PubMed Central

    Salmanoglu, Derya Selcen; Gurpinar, Tugba; Vural, Kamil; Ekerbicer, Nuran; Darıverenli, Ertan; Var, Ahmet

    2016-01-01

    Vascular dysfunction is thought to play a major role in the development of diabetic cardiovascular disease. The roles of endothelial dysfunction, oxidative stress, and dyslipidemia will be considered. Melatonin as well as L-carnitine were shown to possess strong antioxidant properties. Diabetes induced with high fat diet (for 8 weeks) and multipl low doses intraperitoneal injection of STZ (twice, 30 mg/kg/d i.p). The diabetic animals were randomly assigned to one of the experimental groups as follows: Control group (C), high fat diet (HFD), STZ-induced diabetic group (HFD+STZ) , HFD+STZ diabetic group received melatonin (10 mg/kg/d i.p), HFD+STZ diabetic group received L-carnitine (0.6 g/kg/d i.p), and HFD+STZ diabetic group received glibenclamide (5 mg/kg/d, oral). The serum fasting blood glucose, insulin, total cholesterol, HDL- cholesterol, LDL-cholesterol, triglyceride and malondialdehyde (MDA) levels were tested. Acetylcholine induced endothelium-dependent relaxation and sodium nitroprusside induced endothelium-independent relaxation were measured in aortas for estimating endothelial function. Also, glutathione peroxidase (GPx), superoxide dismutase (SOD) and nitric oxide (NO) levels activities were determined in rat liver. According to our results melatonin and L-carnitine treatment decreased fasting blood glucose, total cholesterol, and LDL levels. MDA levels significantly decreased with the melatonin treatment whereas SOD levels were not significantly changed between the groups. The results suggest that especially melatonin restores the vascular responses and endothelial dysfunction in diabetes. PMID:26803481

  16. Effect of S-allylcysteine, a sulphur containing amino acid on iron metabolism in streptozotocin induced diabetic rats.

    PubMed

    Saravanan, Ganapathy; Ponmurugan, Ponnusamy; Begum, Mustapha Shabana

    2013-04-01

    It is suggested that iron may play a role in the pathogenesis of diabetes. Iron is not only chaperoned through its essential functional pathways, but it also causes damage to biological systems by catalyzing the production of reactive oxygen species. So, the parenchymal tissues of several organs are subject to cell injury and functional insufficiency due to excess deposition of iron. The present study investigated the effects of S-allylcysteine (SAC), a sulphur containing amino acid derived from garlic on the changes in iron metabolism induced by oxidative stress in tissues, as well as on serum biochemical parameters of streptozotocin (STZ)-induced diabetic rats. SAC was administered orally for 45days to control and experimental diabetic rats. The effects of SAC on glucose, insulin, serum iron, ferritin, transferrin, serum bilirubin, heart heme oxygenase activity (HO) and ?-aminolevulinicacid dehydratase activity (?-ALA-D) in liver and kidneys were studied. The levels of glucose, iron, ferritin, bilirubin and HO in liver were increased significantly (p<0.05) whereas the levels of insulin, transferrin and ?-ALA-D in tissues were decreased in diabetic rats. Administration of SAC to diabetic rats showed a decrease in blood glucose, iron, ferritin, bilirubin and HO. In addition, the levels of insulin, transferrin and ?-ALA-D activity in tissues were increased in SAC treated diabetic rats. These findings suggest that S-allylcysteine could have a protective effect against alterations in oxidative stress induced iron metabolism in the diabetic state which was evidenced by the capacity of this natural antioxidant to modulate parameters of iron metabolism. PMID:22981633

  17. Characterization of Upper Thoracic Spinal Neurons Receiving Noxious Cardiac and/or Somatic Inputs in Diabetic Rats

    PubMed Central

    Ghorbani, Marie Louise M.; Qin, Chao; Wu, Mingyuan; Farber, Jay P.; Sheykhzade, Majid; Fjalland, Bjarne; Nyborg, Niels C.B.; Foreman, Robert D.

    2011-01-01

    The aim of the present study was to examine spinal processing of cardiac and somatic nociceptive input in rats with STZ-induced diabetes. Type 1 diabetes was induced with streptozotocin (50 mg/kg) in 14 male Sprague-Dawley rats and citrate buffer was injected in 14 control rats. After 411 weeks, the rats were anesthetized with pentobarbital, ventilated and paralyzed. A laminectomy enabled extracellular recording of T3 spinal cord neuronal activity. Intrapericardial administration of a mixture of algogenic chemicals (bradykinin, serotonin, prostaglandin E2 (all at 10?5 M), and adenosine (10?3 M)) was applied to activate nociceptors of cardiac afferent nerve endings. Furthermore, somatic receptive properties were examined by applying innocuous (brush and light pressure) and noxious (pinch) cutaneous mechanical stimuli. Diabetes-induced increases in spontaneous activity were observed in subsets of neurons exhibiting long-lasting excitatory responses to administration of the algogenic mixture. Algogenic chemicals altered activity of a larger proportion of neurons from diabetic animals (73/111) than control animals (55/115, P < 0.05). Some subtypes of neurons exhibiting long-lasting excitatory responses, elicited prolonged duration and others, had a shortened latency. Some neurons exhibiting short-lasting excitatory responses in diabetic animals elicited a shorter latency and some a decreased excitatory change. The size of the somatic receptive field was increased for cardiosomatic neurons from diabetic animals. Cutaneous somatic mechanical stimulation caused spinal neurons to respond with a mixture of hyper- and hypoexcitability. In conclusion, diabetes induced changes in the spinal processing of cardiac input and these might contribute to cardiovascular autonomic neuropathy in patients with diabetes. PMID:21862419

  18. Treadmill exercise decreases incidence of Alzheimers disease by suppressing glycogen synthase kinase-3? expression in streptozotocin-induced diabetic rats

    PubMed Central

    Kim, Dae-Young; Jung, Sun-Young; Kim, Tae-Woon; Lee, Kwang-Sik; Kim, Kijeong

    2015-01-01

    Diabetes is a metabolic disorder, and it is considered as a major risk factor for Alzheimers disease (AD). In the present study, we evaluated whether treadmill exercise ameliorates progression of AD in relation with glycogen synthase kinase-3? (GSK-3?) activity using streptozotocin (STZ)-induced diabetic rats. For this study, step-down avoidance task, immunohistochemistry for glycogen synthase kinase-3? (GSK-3?) and tau, and western blot for phosphor-phosphoinositide 3 kinase (p-PI3K)/PI3K and phosphor-Akt (p-Akt)/Akt were performed. Diabetes mellitus was induced by intraperitoneal injection of STZ. The rats in the exercise groups were made to run on the treadmill for 30 min per one day, five times a week, during 12 weeks. The present results showed that short-term and long-term latencies in the step-down avoidance task were decreased by induction of diabetes, and treadmill exercise inhibited these latencies in the diabetic rats. Induction of diabetes suppressed the ratio of p-PI3K to PI3K and the ratio of p-Akt to Akt, and treadmill exercise increased these ratios in the diabetic rats. The numbers of GSK-3?-positive and tau-positive cells in the hippocampal dentate gyrus was higher in the diabetes-induction group than that in the control group, and treadmill exercise inhibited these numbers in the diabetic rats. In the present study, treadmill exercise suppressed hyperphosphorylation of tau in the hippocampus by decreased GSK-3? activity through PI3K/Akt pathway activation in the diabetic rats. Based on the present results, treadmill exercise may helpful to prevent diabetes-associated AD occurrence. PMID:25960981

  19. Tripterygium Glycosides Tablet Ameliorates Renal Tubulointerstitial Fibrosis via the Toll-Like Receptor 4/Nuclear Factor Kappa B Signaling Pathway in High-Fat Diet Fed and Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Ma, Ze-jun; Zhang, Xiao-na; Li, Li; Yang, Wei; Wang, Shan-shan; Guo, Xin; Sun, Pei; Chen, Li-ming

    2015-01-01

    Tripterygium glycosides tablet (TGT) is a Chinese traditional medicine that has been shown to protect podocytes from injury and reduce the proteinuria. The aim of this study was to assess the effect of TGT on renal tubulointerstitial fibrosis and its potential mechanism in high-fat diet fed and STZ-induced diabetic rats. Rats were randomly divided into normal control rats (NC group), diabetic rats without drug treatment (DM group), and diabetic rats treated with TGT (1, 3, or 6?mg/kg/day, respectively) for 8 weeks. The results showed that 24?h proteinuria and urinary N-acetyl-glucosaminidase (NAG) in diabetic rats were decreased by TGT treatment without affecting blood glucose. Masson's trichrome stains showed that apparent renal tubulointerstitial fibrosis was found in DM group, which was ameliorated by TGT treatment. The expression of ?-SMA was significantly decreased, accompanied by increased expression of E-cadherin in TGT-treated rats, but not in untreated DM rats. Further studies showed that TGT administration markedly reduced expression of TLR4, NF-?B, IL-1?, and MCP-1 in TGT-treated diabetic rats. These results showed that TGT could ameliorate renal tubulointerstitial fibrosis, the mechanism which may be at least partly associated with the amelioration of EMT through suppression of the TLR4/NF-?B pathway. PMID:26347890

  20. Histopathological and behavioral evaluations of the effects of crocin, safranal and insulin on diabetic peripheral neuropathy in rats

    PubMed Central

    Farshid, Amir Abbas; Tamaddonfard, Esmaeal

    2015-01-01

    Objectives: Crocin and safranal, the major constituents of saffron, exert neuroprotective effects. In the present study, we investigated the effects of crocin and safranal (alone or in combination with insulin) on peripheral neuropathy in diabetic rats. Materials and Methods: Diabetes was induced by intraperitoneal (i.p.) injection of 60 mg/kg of streptozotocin (STZ) and confirmed by blood glucose level higher than 250 mg/dl. After confirmation of diabetes, crocin (30 mg/kg, i.p.), safranal (1 mg/kg, i.p.) (alone or in combination with insulin) and insulin (5 IU/kg, s.c.) were administered for eight weeks. Neuropathic pain was evaluated using acetone drop test. Histopathological changes of sciatic nerve were evaluated using light microscope. Blood glucose levels and sciatic nerve malondialdehyde (MDA) contents were also measured. Results: STZ caused cold allodynia, edema and degenerative changes of sciatic nerve, hyperglycemia and an elevation of sciatic nerve MDA levels. Crocin, safranal and insulin improved STZ-induced behavioral, histopathological and biochemical changes. Combined treatments produced more documented improving effects. Conclusion: The results of the present study showed neuroprotective effects of crocin, safranal and insulin in a rat model of diabetic neuropathy. In addition, crocin and safranal enhanced the neuroprotective effect of insulin. The neuroprotective effects of theses chemical compounds could be associated with their anti-hyperglycemic and antioxidant properties. PMID:26468467

  1. Gender-dimorphic regulation of DJ1 and its interactions with metabolic proteins in streptozotocin-induced diabetic rats

    PubMed Central

    Chaudhari, Harmesh N; Kim, Sang Woo; Yun, Jong Won

    2015-01-01

    Regulation of DJ1 is associated with a number of human diseases. To determine the involvement of DJ1 in progression of diabetes in a gender-dependent manner, we investigated its tissue-specific expression in streptozotocin (STZ)-induced diabetic male and female rats in this study. In animal experiments, females showed greater susceptibility towards developing diabetes because of lower insulin secretion and higher blood glucose levels as compared to male diabetic rats upon exposure to STZ. Immunoblotting confirmed sexually dimorphic regulation of DJ1 in various metabolic tissues such as the liver, pancreas and skeletal muscle. Immunofluorescence analysis revealed the location as well as reinforced the gender-dependent expression of DJ1 in hepatic tissue. Co-immunoprecipitation assay identified several interacting proteins with DJ1 whose functions were shown to be involved in various metabolic pathways viz. antioxidative and stress defence system, protein and methionine metabolism, nitrogen metabolism, urea metabolism, etc. Using GeneMANIA, a predictive web interface for gene functions, we showed for the first time that DJ1 may regulate T1DM via the JNK1 pathway, suggesting DJ1 interacts with other proteins from various metabolic pathways. We anticipate that the current data will provide insights into the aetiology of T1DM. PMID:25726699

  2. Characterization of L-type calcium channel activity in atrioventricular nodal myocytes from rats with streptozotocin-induced Diabetes mellitus

    PubMed Central

    Yuill, Kathryn H; Al Kury, Lina T; Howarth, Frank Christopher

    2015-01-01

    Cardiovascular complications are common in patients with Diabetes mellitus (DM). In addition to changes in cardiac muscle inotropy, electrical abnormalities are also commonly observed in these patients. We have previously shown that spontaneous cellular electrical activity is altered in atrioventricular nodal (AVN) myocytes, isolated from the streptozotocin (STZ) rat model of type-1 DM. In this study, utilizing the same model, we have characterized the changes in L-type calcium channel activity in single AVN myocytes. Ionic currents were recorded from AVN myocytes isolated from the hearts of control rats and from those with STZ-induced diabetes. Patch-clamp recordings were used to assess the changes in cellular electrical activity in individual myocytes. Type-1 DM significantly altered the cellular characteristics of L-type calcium current. A reduction in peak ICaL density was observed, with no corresponding changes in the activation parameters of the current. L-type calcium channel current also exhibited faster time-dependent inactivation in AVN myocytes from diabetic rats. A negative shift in the voltage dependence of inactivation was also evident, and a slowing of restitution parameters. These findings demonstrate that experimentally induced type-1 DM significantly alters AVN L-type calcium channel cellular electrophysiology. These changes in ion channel activity may contribute to the abnormalities in cardiac electrical function that are associated with high mortality levels in patients with DM. PMID:26603460

  3. Pulsed electromagnetic fields inhibit bone loss in streptozotocin-induced diabetic rats.

    PubMed

    Zhou, Jun; Li, Xinhong; Liao, Ying; Feng, Weibing; Fu, Chengxiao; Guo, Xin

    2015-05-01

    Evidences have shown that pulsed electromagnetic fields (PEMFs) can partially prevent bone loss in streptozotocin (STZ)-induced diabetic rats. However, the precise mechanisms accounting for these favorable effects are unclear. This study aimed to investigate the effects of PEMFs on bone mass and receptor activator of nuclear factor κB ligand (RANKL)/osteoprotegerin (OPG) and Wnt/β-catenin signaling pathway in STZ rats. Thirty 3-month-old Sprague Dawley rats were randomly divided into the following three groups (n = 10): control group (injection of saline vehicle), DM group (injection of STZ), and PEMFs group (injection of STZ + PEMFs exposure). One week following injection of STZ, rats in the PEMFs group were subject to PEMFs stimulus for 40 min/day, 5 days/week, and lasted for 12 weeks. After 12 week intervention, the results showed that PEMFs increased serum bone-specific alkaline phosphatase level and bone mineral density, and inhibited deterioration of bone microarchitecture and strength in STZ rats. Furthermore, PEMFs up-regulated the mRNA expressions of low-density lipoprotein receptor-related protein 5, β-catenin and runt-related gene 2 (Runx2), and down-regulated dickkopf1 in STZ rats. However, mRNA expressions of RANKL and OPG were not affected by PEMFs. PEMFs can prevent the diabetes-induced bone loss and reverse the deterioration of bone microarchitecture and strength by restoring Runx2 expression through regulation of Wnt/β-catenin signaling, regardless of its no glucose lowering effect. PMID:25273319

  4. Effect of the Combination of Gelam Honey and Ginger on Oxidative Stress and Metabolic Profile in Streptozotocin-Induced Diabetic Sprague-Dawley Rats

    PubMed Central

    Abdul Sani, Nur Fathiah; Belani, Levin Kesu; Pui Sin, Chong; Abdul Rahman, Siti Nor Amilah; Zar Chi, Thent; Makpol, Suzana; Yusof, Yasmin Anum Mohd

    2014-01-01

    Diabetic complications occur as a result of increased reactive oxygen species (ROS) due to long term hyperglycaemia. Honey and ginger have been shown to exhibit antioxidant activity which can scavenge ROS. The main aim of this study was to evaluate the antioxidant and antidiabetic effects of gelam honey, ginger, and their combination. Sprague-Dawley rats were divided into 2 major groups which consisted of diabetic and nondiabetic rats. Diabetes was induced with streptozotocin intramuscularly (55?mg/kg body weight). Each group was further divided into 4 smaller groups according to the supplements administered: distilled water, honey (2?g/kg body weight), ginger (60?mg/kg body weight), and honey + ginger. Body weight and glucose levels were recorded weekly, while blood from the orbital sinus was obtained after 3 weeks of supplementation for the estimation of metabolic profile: glucose, triglyceride (TG), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH): oxidized glutathione (GSSG), and malondialdehyde (MDA). The combination of gelam honey and ginger did not show hypoglycaemic potential; however, the combination treatment reduced significantly (P < 0.05) SOD and CAT activities as well as MDA level, while GSH level and GSH/GSSG ratio were significantly elevated (P < 0.05) in STZ-induced diabetic rats compared to diabetic control rats. PMID:24822178

  5. Effect of the combination of gelam honey and ginger on oxidative stress and metabolic profile in streptozotocin-induced diabetic Sprague-Dawley rats.

    PubMed

    Sani, Nur Fathiah Abdul; Belani, Levin Kesu; Sin, Chong Pui; Rahman, Siti Nor Amilah Abdul; Das, Srijit; Chi, Thent Zar; Makpol, Suzana; Yusof, Yasmin Anum Mohd

    2014-01-01

    Diabetic complications occur as a result of increased reactive oxygen species (ROS) due to long term hyperglycaemia. Honey and ginger have been shown to exhibit antioxidant activity which can scavenge ROS. The main aim of this study was to evaluate the antioxidant and antidiabetic effects of gelam honey, ginger, and their combination. Sprague-Dawley rats were divided into 2 major groups which consisted of diabetic and nondiabetic rats. Diabetes was induced with streptozotocin intramuscularly (55 mg/kg body weight). Each group was further divided into 4 smaller groups according to the supplements administered: distilled water, honey (2 g/kg body weight), ginger (60 mg/kg body weight), and honey + ginger. Body weight and glucose levels were recorded weekly, while blood from the orbital sinus was obtained after 3 weeks of supplementation for the estimation of metabolic profile: glucose, triglyceride (TG), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH): oxidized glutathione (GSSG), and malondialdehyde (MDA). The combination of gelam honey and ginger did not show hypoglycaemic potential; however, the combination treatment reduced significantly (P < 0.05) SOD and CAT activities as well as MDA level, while GSH level and GSH/GSSG ratio were significantly elevated (P < 0.05) in STZ-induced diabetic rats compared to diabetic control rats. PMID:24822178

  6. Immunohistochemical expressions of adropin and ?nducible nitric oxide synthase in renal tissues of rats with streptozotocin-?nduced experimental diabetes.

    PubMed

    Kuloglu, T; Aydin, S

    2014-02-01

    Diabetes is characterized by high blood glucose levels; it occurs in 30-35% of the population. Elevated glucose levels can damage a number of organs, including the kidneys. Several peptide hormones participate in maintaining glucose homeostasis including the recently discovered "adropin," a 42 amino acid peptide hormone. Adropin also alters inducible nitric oxide synthase (iNOS) expression. Therefore, we studied how adropin and iNOS expression is altered in the renal tissues of streptozotocin (STZ) induced diabetic rats. Seven sham, seven control and seven Wistar albino male rats were fed standard rat pellets and water ad libitum for 10 weeks. The rats in the diabetic group were injected i.p. with a single dose of 60 mg/kg STZ dissolved in 0.1 M phosphate-citrate buffer, pH 4.5. After the 10-week experimental period, the rats in both groups were anesthetized and decapitated. Kidney tissues were excised and placed in 10% formaldehyde solution, taken through routine histological procedures, and embedded in paraffin. Sections 5-6 ?m thick were stained immunohistochemically using the avidin-biotin complex (ABC) method. Adropin and iNOS immunoreactivity were co-localized in the glomeruli, peritubular interstitial cells and peritubular capillary endothelium of the cortex; the thin limb of the loop of Henle in the medulla; and medullary peritubular interstitial cells and endothelium of the peritubular capillaries in both the control and diabetic groups. The intensities of adropin and iNOS immunoreactivity increased with the severity of the diabetes. Intense adropin immunoreactivity was detected in both the smooth muscle and human small intestine Paneth cells that were used as positive controls. The elevated levels of adropin and iNOS in the kidney indicates that these substances are involved in the pathophysiology of diabetes; this constitutes a compensatory mechanism against the damage inflicted by the disease. PMID:23957703

  7. Attenuation of Ca2+ homeostasis, oxidative stress, and mitochondrial dysfunctions in diabetic rat heart: insulin therapy or aerobic exercise?

    PubMed

    da Silva, Mrcia F; Natali, Antnio J; da Silva, Edson; Gomes, Gilton J; Teodoro, Bruno G; Cunha, Daise N Q; Drummond, Lucas R; Drummond, Filipe R; Moura, Anselmo G; Belfort, Felipe G; de Oliveira, Alessandro; Maldonado, Izabel R S C; Alberici, Luciane C

    2015-07-15

    We tested the effects of swimming training and insulin therapy, either alone or in combination, on the intracellular calcium ([Ca(2+)]i) homeostasis, oxidative stress, and mitochondrial functions in diabetic rat hearts. Male Wistar rats were separated into control, diabetic, or diabetic plus insulin groups. Type 1 diabetes mellitus was induced by streptozotocin (STZ). Insulin-treated groups received 1 to 4 UI of insulin daily for 8 wk. Each group was divided into sedentary or exercised rats. Trained groups were submitted to swimming (90 min/day, 5 days/wk, 8 wk). [Ca(2+)]i transient in left ventricular myocytes (LVM), oxidative stress in LV tissue, and mitochondrial functions in the heart were assessed. Diabetes reduced the amplitude and prolonged the times to peak and to half decay of the [Ca(2+)]i transient in LVM, increased NADPH oxidase-4 (Nox-4) expression, decreased superoxide dismutase (SOD), and increased carbonyl protein contents in LV tissue. In isolated mitochondria, diabetes increased Ca(2+) uptake, susceptibility to permeability transition pore (MPTP) opening, uncoupling protein-2 (UCP-2) expression, and oxygen consumption but reduced H2O2 release. Swimming training corrected the time course of the [Ca(2+)]i transient, UCP-2 expression, and mitochondrial Ca(2+) uptake. Insulin replacement further normalized [Ca(2+)]i transient amplitude, Nox-4 expression, and carbonyl content. Alongside these benefits, the combination of both therapies restored the LV tissue SOD and mitochondrial O2 consumption, H2O2 release, and MPTP opening. In conclusion, the combination of swimming training with insulin replacement was more effective in attenuating intracellular Ca(2+) disruptions, oxidative stress, and mitochondrial dysfunctions in STZ-induced diabetic rat hearts. PMID:25997948

  8. The effects of Cetraria islandica and Pseudevernia furfuracea extracts in normal and diabetic rats.

    PubMed

    Bak?r, Tlay zhan; Geyikoglu, Fatime; olak, Suat; Trkez, Hasan; Aslan, Ali; Bak?r, Murat

    2015-12-01

    Lichens are symbiotic organisms composed of a fungus joined to a photosynthesizing partner that can be either an alga or a cyanobacterium. They can be used as a novel bioresource for natural antioxidants. However, there is also a need for further studies to validate the lichens used in medicinal remedies. This study covers a previously unrecognized effects of Cetraria islandica (CIAE) and Pseudevernia furfuracea (PFAE) in streptozotocin (STZ)-induced diabetes. In experimental design, control or diabetic rats were either untreated or treated with aqueous lichen extracts (250-500 mg/kg/day) for 2 weeks starting at 72 h after STZ injection. On day 14, animals were anesthetized, metabolic and biochemical parameters were appreciated between control and treatment groups. The histopathology of kidney was examined using four different staining methods: hematoxylin-eosin (H&E), periodic acid-Schiff (PAS), Masson trichrome and Congo red. Our experimental data showed that increasing doses of CIAE and PFAE did not have any detrimental effects on the studied parameters and the malondialdehyde level of kidney. CIAE extract showed prominent results compared to doses of PFAE extract for antioxidant capacity. However, the protective effect of CIAE extract was inadequate on diabetes-induced disorders and kidney damages. Moreover, animals subjected to diabetes mellitus (DM) therapy did not benefit unfortunately from the usage of increasing lichen doses due to their unchanged antioxidant activity to tissue. The results obtained in present study suggested that CIAE and PFAE are safe but the power of these is limited because of the intensive oxidative stress in kidney of type 1 diabetic rats. It is also implied that CIAE extract is especially suitable for different administration routes in DM. PMID:23833245

  9. Caffeic acid phenethyl amide ameliorates ischemia/reperfusion injury and cardiac dysfunction in streptozotocin-induced diabetic rats

    PubMed Central

    2014-01-01

    Background Caffeic acid phenethyl ester (CAPE) has been shown to protect the heart against ischemia/reperfusion (I/R) injury by various mechanisms including its antioxidant effect. In this study, we evaluated the protective effects of a CAPE analog with more structural stability in plasma, caffeic acid phenethyl amide (CAPA), on I/R injury in streptozotocin (STZ)-induced type 1 diabetic rats. Methods Type 1 diabetes mellitus was induced in Sprague–Dawley rats by a single intravenous injection of 60 mg/kg STZ. To produce the I/R injury, the left anterior descending coronary artery was occluded for 45 minutes, followed by 2 hours of reperfusion. CAPA was pretreated intraperitoneally 30 minutes before reperfusion. An analog devoid of the antioxidant property of CAPA, dimethoxyl CAPA (dmCAPA), and a nitric oxide synthase (NOS) inhibitor (Nω-nitro-l-arginine methyl ester [l-NAME]) were used to evaluate the mechanism involved in the reduction of the infarct size following CAPA-treatment. Finally, the cardioprotective effect of chronic treatment of CAPA was analyzed in diabetic rats. Results Compared to the control group, CAPA administration (3 and 15 mg/kg) significantly reduced the myocardial infarct size after I/R, while dmCAPA (15 mg/kg) had no cardioprotective effect. Interestingly, pretreatment with a NOS inhibitor, (l-NAME, 3 mg/kg) eliminated the effect of CAPA on myocardial infarction. Additionally, a 4-week CAPA treatment (1 mg/kg, orally, once daily) started 4 weeks after STZ-induction could effectively decrease the infarct size and ameliorate the cardiac dysfunction by pressure-volume loop analysis in STZ-induced diabetic animals. Conclusions CAPA, which is structurally similar to CAPE, exerts cardioprotective activity in I/R injury through its antioxidant property and by preserving nitric oxide levels. On the other hand, chronic CAPA treatment could also ameliorate cardiac dysfunction in diabetic animals. PMID:24923878

  10. Antidiabetic, renal/hepatic/pancreas/cardiac protective and antioxidant potential of methanol/dichloromethane extract of Albizzia Lebbeck Benth. stem bark (ALEx) on streptozotocin induced diabetic rats

    PubMed Central

    2014-01-01

    Background Hypoglycemic and/or anti-hyperglycemic activities have been recorded with numerous plants, many of which are used as traditional herbal treatments of diabetes. Albizzia Lebbeck Benth. stem bark have been used in traditional medicine along with some preliminary reports on its hypoglycemic action. The aim of present investigation was to evaluate the antidiabetic and antioxidant activities of methanolic extract of stem bark of Albizzia Lebbeck Benth. in streptozotocin induced diabetic rats. Methods The powdered stem bark of Albizzia Lebbeck Benth.. was extracted with methanol (MeOH) using soxhlation method and subjected to phytochemical analysis. The methanol/dichloromethane extract of Albizzia Lebbeck Benth. (ALEx) was concentrated to dryness using Rotary Evaporator. Diabetes was experimentally induced in the rats by single intraperitoneal administration of Streptozotocin (60 mg/kg). They glycemic control was measured by the blood glucose, glycated heamoglobin and plasma insulin. The oxidative stress was evaluated in the liver and kidney by level of antioxidant markers and various biochemical parameters were assessed in diabetic control and extract treated rats. Results Streptozotocin induced diabetic rats depicted the increased blood glucose levels, total cholesterol (TC), triglycerides (TG), low density lipoprotein cholesterol (LDL-c), diminished level of high density lipoprotein cholesterol (HDL-c) level and perturb level of antioxidant markers. Oral administration of MeAL at a concentration of 100, 200, 300 and 400 mg/kg b.w daily for 30 days results a momentous decrease in fasting blood glucose, glycated heamoglobin and enhancement of plasma insulin level as compared with STZ induced diabetic rats. Furthermore, it significantly (p < 0.05) decreased the level of TC, TG, and LDL-c, VLDL-c. While it increases the level of HDL-c to a significant (p < 0.05) level. The treatment also resulted in a marked increase in reduced glutathione, glutathione Peroxidase, catalase and superoxide dismutase and diminished level of lipid peroxidation in liver and kidney of STZ induced diabetic rats. Histopathological studies suggest the diminution in the pancreatic, liver and cardiac muscle damage. Conclusion Our research exertion clearly indicates the considerable antihyperglycemic, antihyperlipidemic, antioxidant & pancreas/renal/hepatic/cardiac protective action of ALEx. PMID:25026962

  11. The Effects of the Melatonin Treatment on the Oxidative Stress and Apoptosis in Diabetic Eye and Brain

    PubMed Central

    Gürpınar, Tuğba; Ekerbiçer, Nuran; Uysal, Nazan; Barut, Turgay; Tarakçı, Figen; Tuglu, M. Ibrahim

    2012-01-01

    Oxidative stress plays an important role in the development of complications in diabetes mellitus. Antioxidant therapy has been thought to decrease oxidative stress. The objective of the present study was to explore the effects of melatonin (MLT) on oxidative stress in diabetic rat eye and brain tissue by using immunohistochemical methods. Diabetes was induced by streptozotocin, (STZ, 55 mg/kg/i.p) in adult rats. MLT was given 10 mg/kg/i.p once a day for 2 weeks beginning from the sixth week. Six weeks later, rats were divided into three groups: control (CR), STZ-induced diabetic (STZ), and STZ-induced diabetic group received melatonin (STZ+MLT). Although no significant difference was observed with respect to antioxidant status, NOS activity tended to be higher in the untreated diabetic rats than in the treated rats. It was observed that MLT treatment improved the histopathological changes including apoptosis and oxidative stress in brain and eye in diabetic rat. PMID:22654617

  12. Proteomic profile of primary isolated rat mesangial cells in high-glucose culture condition and decreased expression of PSMA6 in renal cortex of diabetic rats.

    PubMed

    Li, Zhiguo; Zhang, Haojun; Dong, Xi; Burczynski, Frank J; Choy, Patrick; Yang, Fang; Liu, Hui; Li, Ping; Gong, Yuewen

    2010-08-01

    Diabetic nephropathy (DN) is one of the most important complications of diabetic patients and is characterized histologically by an accumulation of extracellular matrix (ECM) protein in the glomerular mesangium. Therefore, mesangial cells likely play an important role in the development of diabetic nephropathy. Here, we employed proteomic techniques to investigate the protein profile of rat mesangial cells under high-glucose culture conditions. Primary isolated rat glomerular mesangial cells were cultured under different concentrations of glucose (5.4 mmol.L-1 for normal control and 30 mmol.L-1 for high glucose) for 0, 8, 16, and 72 h, as well as for 25 days. Cellular total proteins were isolated from these cells and employed for two-dimensional gel electrophoresis (2-DE). Differentially expressed proteins were identified by matrix-assisted laser desorption - ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and some of these proteins were documented in rat models of diabetes by Western blot. Rat mesangial cells were successfully isolated in the laboratory and their proliferation rates were significantly inhibited by high glucose. Two-dimensional gel electrophoresis analyses revealed 28 differentially expressed protein spots between the normal and high-glucose groups. After MALDI-TOF-MS analysis, all 28 protein spots were successfully identified with the peptide mass fingerprint (PMF) method. Representatively, SOD1, PCBP1 and PSMA6 were validated by Western blot analysis following protein extractions from the normal and high-glucose groups. Abundance of these proteins was consistent with that found in 2-DE. Moreover, expression of SOD1, PCBP1, and PSMA6 in renal cortex was further examined in two rat models of diabetes (streptozotocin-induced and spontaneous OLETF diabetic models). Abundance of SOD1 and PCBP1 proteins did not show any significant difference between normal control and diabetic rats. However, abundance of the PSMA6 protein was significantly reduced in the renal cortex of both STZ-induced and spontaneous OLETF diabetic rats. Proteomic analysis identified 28 differentially expressed proteins in primary isolated rat mesangial cells between normal and high glucose treatments. Expression of one identified protein was found to be consistent with expression in the renal cortex of two rat diabetic models. Therefore, identification of protein expression patterns in mesangial cells can be employed to develop a therapeutic target for treatment of diabetic nephropathy. PMID:20651835

  13. [Protective effect of calcium dobesilate against early diabetic nephropathy of rat kidney].

    PubMed

    Gao, Mei-Juan; Liu, Ming; Li, Bo; Li, Ming-Long; Bian, Li-Xiang; Yu, Gui-Na

    2009-02-01

    The aim of this study is to study the effect of calcium dobesilate on streptozotocin (STZ)-induced early diabetic nephrophathy (DN) in rats. All male Wistar rats were randomly divided into six groups: normal group; DN blank group; calcium dobesilate 75, 150, and 300 mg x kg(-1) groups and perindopril 0.4 mg x kg(-1) group. Blood glucose and the 24 h urinary albumin were measured dynamically during the experiment, after 8 weeks administration, the level of glycosylated hemoglobin (HbA1c) was determined, the expressions of plasminogen activator inhibitor-1 (PAI-1) and matrix metalloprotein-9 (MMP-9) in cortex of kidney were examined with immunohistochemical staining. The endothelin (ET) in plasma and kidney cortex was measured with radioimmunoassay, renal pathomorphism was observed with light and electron microscopes. Calcium dobesilate could decrease the 24 h urinary albumin and ET in plasma and kidney cortex, down-regulate the expression of PAI-1, and up-regulate MMP-9 in kidney. These findings suggested that calcium dobesilate could protect blood vessel endothelium, inhibit kidney fibrous degeneration, ameliorate renal pathological damage, and protect kidney function in many ways. PMID:19408680

  14. Microemulsions for oral delivery of insulin: design, development and evaluation in streptozotocin induced diabetic rats.

    PubMed

    Sharma, G; Wilson, K; van der Walle, C F; Sattar, N; Petrie, J R; Ravi Kumar, M N V

    2010-10-01

    Insulin loaded microemulsions were developed adopting a low shear reverse micellar approach using didoceyldimethylammonium bromide (DMAB) as the surfactant, propylene glycol (PG) as the co-surfactant, triacetin (TA) as the oil phase and insulin solution as the aqueous phase. A ternary phase diagram was constructed based on multiple cloud point titration to highlight the reverse micellar region. The droplet sizes of the microemulsions were 161.7±24.7nm with PDI of 0.447±0.076 and insulin entrapment of ∼85%. Transmission electron microscopy (TEM) revealed the spherical nature and size homogeneity of the microemulsion droplets. The conformational stability of the entrapped insulin within microemulsions was confirmed by fluorescence spectroscopy and circular dichroism. The microemulsions displayed a 10-fold enhancement in bioavailability compared with plain insulin solution administered per oral in healthy rats. The short-term in vivo efficacy in STZ induced diabetic rats provided the proof of concept by a modest glucose reduction at a dose of 20IU/kg. Together this preliminary data indicate the promise of microemulsions for oral delivery of insulin. PMID:20655382

  15. The Antidiabetic Effect of Garlic Oil is Associated with Ameliorated Oxidative Stress but Not Ameliorated Level of Pro-inflammatory Cytokines in Skeletal Muscle of Streptozotocin-induced Diabetic Rats.

    PubMed

    Liu, Cheng-Tzu; Hsu, Tien-Wei; Chen, Ke-Ming; Tan, Ya-Ping; Lii, Chong-Kuei; Sheen, Lee-Yan

    2012-04-01

    Oxidative stress and inflammatory condition has been broadly accepted being associated with the progression of diabetes. On the other hand, garlic ( d sun, bulb of Allium sativum) has been shown to possess both antioxidant and anti-inflammatory action in several clinical conditions. Our previous study demonstrated that treatment with garlic oil improves oral glucose tolerance and insulin tolerance and improves the insulin-stimulated utilization of glucose to synthesize glycogen in skeletal muscle in streptozotocin (STZ)-induced diabetes, in vivo and ex vivo, respectively. The aim of the present study is to investigate the antioxidant and anti-inflammatory effects of garlic oil (GO) in the skeletal muscle of diabetic rats. Rats with STZ-induced diabetes received GO (10, 50, or 100 mg/kg body weight) or corn oil by gavage every other day for 3 weeks. Control rats received corn oil only. GO dose-dependently improved insulin sensitivity, as assessed by the insulin tolerance test, and oral glucose tolerance. GO significantly elevated total glutathione and glutathione peroxidase activity and lowered the nitrate/nitrite content in skeletal muscle at 50 and 100 mg/kg and significantly elevated glutathione reductase activity and lowered lipid peroxidation at 100 mg/kg. By contrast, GO did not reverse diabetes-induced elevation of IL-1? and TNF-? in skeletal muscle at any tested dose. On the other hand, GO elevated the expression of GLUT4 in skeletal muscle along with glycogen content as observed with PAS staining. In conclusion, the antidiabetic effect of garlic oil is associated with ameliorated oxidative stress in skeletal muscle. PMID:24716126

  16. Limiting prolonged inflammation during proliferation and remodeling phases of wound healing in streptozotocin-induced diabetic rats supplemented with camel undenatured whey protein

    PubMed Central

    2013-01-01

    Background Impaired diabetic wound healing occurs as a consequence of excessive reactive oxygen species (ROS) and inflammatory cytokine production. We previously found that whey protein (WP) was able to normally regulate the ROS and inflammatory cytokines during the inflammatory phase (first day) in streptozotocin (STZ)-diabetic wound healing. This study was designed to assess the effect of WP on metabolic status, the inflammation and anti-inflammation response, oxidative stress and the antioxidant defense system during different phases of the wound healing process in diabetic rats. WP at a dosage of 100 mg/kg of body weight, dissolved in 1% CMC, was orally administered daily to wounded normal (non-diabetic) and STZ-induced diabetic rats for 8 days starting from the 1st day after wounding. Results The data revealed that WP enhanced wound closure and was associated with an increase in serum insulin levels in diabetic rats and an alleviation of hyperglycemic and hyperlipidemic states in diabetic animals. The increase in insulin levels as a result of WP administration is associated with a marked multiplication of ?-cells in the core of islets of Langerhans. WP induced a reduction in serum TNF-?, IL-1? and IL-6 levels and an increase in IL-10 levels, especially on the 4th day after wounding and treatment. WP also suppressed hepatic lipid peroxidation and stimulated the antioxidant defense system by increasing the level of glutathione and the activity of glutathione-S-transferase, glutathione peroxidase and superoxide dismutase (SOD) in wounded diabetic rats. Conclusions WP was observed to enhance wound closure by improving the diabetic condition, limiting prolonged inflammation, suppressing oxidative stress and elevating the antioxidant defense system in diabetic rats. PMID:23883360

  17. Preventive effect of danhong huayu koufuye on diabetic retinopathy in rats

    PubMed Central

    Lin, Bao-Qin; Zhou, Jiu-Yao; Ma, Yan; Deng, Ying-Jun; Zheng, Chuan-Jie; Lin, Jun-Li

    2011-01-01

    AIM To study the effects of danhong huayu koufuye (DHK) on fasting blood glucose (FBG) and diabetic retinopathy (DR) in streptozotocin (STZ)-induced type 1 diabetic rats to facilitate the rational usage of this drug. METHODS Diabetic rats were induced by injection of a single dose of STZ intraperitoneally at 50mg/kg. Flash electroretinogram (FERG) and oscillatory potentials (OPs) were used to measure retinal function. The microvascular perfusion of ears was performed to study the microcirculation in rats. FBG, body-weight, and 24-h urine volume, water intake and diet intake were also assessed. RESULTS DHK had no effect on FBG in normal rats. However, STZ + DHK group were significantly different from those of Model and moved toward those of normal control. It reversed the increase in diet intake (P?0.05 vs model control) and the loss in body-weight (P?0.05 vs model control) in diabetic rats. DHK decreased the FBG of diabetic rats by 25.6% (P?0.05) and 37.9% (P?0.01) after 14 and 21 days administration as compared with the model control, respectively. Moreover, DHK significantly increased the FERG b-wave amplitude by 80% (P?0.05 vs model control) and decreased the FERG b-wave latency by 15.3% (P?0.01 vs model control) after 24 days administration. The OP1 and OP2 amplitudes in DHK group were 2.6 (P?0.01) and 2.0 (P?0.01) times of model group after 24 days of DHK treatment, respectively. At the same time, OP1 and OP2 latencies in DHK group reduced by 16.0% (P?0.001) and 14.7% (P?0.001) as compared with the model control, respectively. Furthermore, the microvascular perfusion of DHK group was 2.4 times of model group (P?0.001) after 21 days administration. CONCLUSION DHK had no effect on normal FBG. But it had antihyperglycemic activity, and had a preventive and therapeutic effect on DR in diabetic rats. PMID:22553728

  18. Therapeutic Effects of 15 Hz Pulsed Electromagnetic Field on Diabetic Peripheral Neuropathy in Streptozotocin-Treated Rats

    PubMed Central

    Jiang, Maogang; Li, Feijiang; Cai, Jing; Wu, Xiaoming; Tang, Chi; Xu, Qiaoling; Liu, Juan; Guo, Wei; Shen, Guanghao; Luo, Erping

    2013-01-01

    Although numerous clinical studies have reported that pulsed electromagnetic fields (PEMF) have a neuroprotective role in patients with diabetic peripheral neuropathy (DPN), the application of PEMF for clinic is still controversial. The present study was designed to investigate whether PEMF has therapeutic potential in relieving peripheral neuropathic symptoms in streptozotocin (STZ)-induced diabetic rats. Adult male SpragueDawley rats were randomly divided into three weight-matched groups (eight in each group): the non-diabetic control group (Control), diabetes mellitus with 15 Hz PEMF exposure group (DM+PEMF) which were subjected to daily 8-h PEMF exposure for 7 weeks and diabetes mellitus with sham PEMF exposure group (DM). Signs and symptoms of DPN in STZ-treated rats were investigated by using behavioral assays. Meanwhile, ultrastructural examination and immunohistochemical study for vascular endothelial growth factor (VEGF) of sciatic nerve were also performed. During a 7-week experimental observation, we found that PEMF stimulation did not alter hyperglycemia and weight loss in STZ-treated rats with DPN. However, PEMF stimulation attenuated the development of the abnormalities observed in STZ-treated rats with DPN, which were demonstrated by increased hind paw withdrawal threshold to mechanical and thermal stimuli, slighter demyelination and axon enlargement and less VEGF immunostaining of sciatic nerve compared to those of the DM group. The current study demonstrates that treatment with PEMF might prevent the development of abnormalities observed in animal models for DPN. It is suggested that PEMF might have direct corrective effects on injured nerves and would be a potentially promising non-invasive therapeutic tool for the treatment of DPN. PMID:23637830

  19. Carbamylated erythropoietin attenuates cardiomyopathy via PI3K/Akt activation in rats with diabetic cardiomyopathy

    PubMed Central

    HE, HONGYING; QIAO, XIAOYU; WU, SUISHENG

    2013-01-01

    The aim of the present study was to investigate the protective effect of carbamylated erythropoietin (CEPO) against cardiomyopathy in high-fat, high-carbohydrate diet-fed rats with streptozotocin (STZ)-induced diabetic cardiomyopathy (DCM). Healthy male Wistar rats were fed a high-fat, high-carbohydrate diet for four weeks, and then were injected with STZ twice (50 mg/kg, intraperitoneally). Once DCM was confirmed, the rats were divided randomly into the following groups: DCM without treatment, CEPO treatment at different dosages (500, 1,000 or 2,000 IU/kg) or recombinant human erythropoietin (rhEPO) treatment (1,000 IU/kg), for a four-week short intervention or an eight-week long intervention protocol. Healthy rats were used as normal controls. Venous blood samples were drawn for routine hematological examinations, and heart tissues were collected for histological analysis, as well as the determination of myocardial apoptosis and phosphatidylinositol-3-kinase (PI3K)/Akt signaling. CEPO treatment had no significant effect on the erythrocyte or hemoglobin levels in the rats with DCM; however, it reduced myocardial cell apoptosis in the rats and protected the cellular ultrastructure. In addition, CEPO treatment inhibited caspase-3 and increased Bcl-xl protein expression (P<0.05). It also increased PI3K (p85) and Akt1 expression at the mRNA and protein levels in the hearts of the rats with DCM, with a dose-response relationship. An eight-week treatment using CEPO, in comparison with a four-week protocol, marginally increased PI3K (p85) and Akt1 expression, and did not demonstrate significant benefit. The study indicated that CEPO protects against DCM, without markedly affecting erythropoiesis, and that the activation of PI3K/Akt may be a key mechanism in the protection conferred by CEPO. PMID:24137228

  20. Protective Effects of the Mushroom Lactarius deterrimus Extract on Systemic Oxidative Stress and Pancreatic Islets in Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Mihailović, Mirjana; Arambašić Јovanović, Jelena; Uskoković, Aleksandra; Grdović, Nevena; Dinić, Svetlana; Vidović, Senka; Poznanović, Goran; Mujić, Ibrahim; Vidaković, Melita

    2015-01-01

    The aim of this study was to assess the in vivo effects of the extract of the medicinal mushroom, Lactarius deterrimus, when administered (60 mg/kg, i.p.) daily for four weeks to streptozotocin- (STZ-) induced diabetic rats. Diabetic rats treated with the L. deterrimus extract displayed several improved biochemical parameters in the circulation: reduced hyperglycemia, lower triglyceride concentration and reduced glycated hemoglobin, glycated serum protein, and advanced glycation end product (AGE) levels. This treatment also adjusted the diabetes-induced redox imbalance. Thus, higher activities of the antioxidative enzymes, superoxide dismutase, and catalase in the circulation were accompanied by increased levels of free intracellular thiols and glutathionylated proteins after treatment with the L. deterrimus extract. In addition to a systemic antioxidant effect, the administration of the extract to diabetic rats also had a positive localized effect on pancreatic islets where it decreased AGE formation, and increased the expression of chemokine CXCL12 protein that mediates the restoration of β-cell population through the activation of the serine/threonine-specific Akt protein kinase prosurvival pathway. As a result, the numbers of proliferating cell nuclear antigen- (PCNA-) and insulin-positive β-cells were increased. These results show that the ability of the L. deterrimus extract to alleviate oxidative stress and increase β-cell mass represents a therapeutic potential for diabetes management. PMID:26221612

  1. Upregulation of PPAR? by Aegle marmelos ameliorates insulin resistance and ?-cell dysfunction in high fat diet fed-streptozotocin induced type 2 diabetic rats.

    PubMed

    Sharma, Ashok Kumar; Bharti, Saurabh; Goyal, Sameer; Arora, Sachin; Nepal, Saroj; Kishore, Kamal; Joshi, Sujata; Kumari, Santosh; Arya, Dharamvir Singh

    2011-10-01

    The global epidemic of type 2 diabetes demands the rapid evaluation of new and accessible interventions. This study investigated whether Aegle marmelos fruit aqueous extract (AMF; 250, 500 and 1000?mg/kg) improves insulin resistance, dyslipidemia and ?-cell dysfunction in high fat diet fed-streptozotocin (HFD-STZ)-induced diabetic rats by modulating peroxisome proliferator-activated receptor-? (PPAR?) expression. The serum levels of glucose, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), homeostasis model assessment of ?-cell function (HOMA-B), lipid profile, TNF-? and IL-6 were evaluated. Further, the TBARS level and SOD activity in pancreatic tissue and PPAR? protein expression in liver were assessed. In addition, histopathological and ultrastructural studies were performed to validate the effect of AMF on ?-cells. The HFD-STZ treated rats showed a significant increase in the serum levels of glucose, insulin, HOMA-IR, TNF-?, IL-6, dyslipidemia with a concomitant decrease in HOMA-B and PPAR? expression. Treatment with AMF for 21?days in diabetic rats positively modulated the altered parameters in a dose-dependent manner. Furthermore, AMF prevented inflammatory changes and ?-cell damage along with a reduction in mitochondrial and endoplasmic reticulum swelling. These findings suggest that the protective effect of AMF in type 2 diabetic rats is due to the preservation of ?-cell function and insulin-sensitivity through increased PPAR? expression. PMID:21351301

  2. Allicin protects against myocardial apoptosis and fibrosis in streptozotocin-induced diabetic rats.

    PubMed

    Liu, Yang; Qi, Hanping; Wang, Ye; Wu, Mingli; Cao, Yonggang; Huang, Wei; Li, Lei; Ji, Zhong; Sun, Hongli

    2012-06-15

    To evaluate the cardioprotective effect of allicin (AL) on myocardial injury of streptozotocin (STZ)-induced diabetic rats and to further explore its underlying mechanisms. Hyperglycemia was induced in rats by single intraperitoneal injection of STZ (40 mg/kg). Three days after STZ induction, the hyperglycemic rats (plasma glucose levels ? 16.7 mmol/l) were treated with AL by intraperitoneal injection at the doses of 4 mg/kg, 8 mg/kg, and 16 mg/kg daily for 28 days. The fasting blood glucose levels were measured on every 7th day during the 28 days of treatment. The body weight, blood glucose, and parameter of cardiac function were detected after 4 weeks to study the cardioprotective effects of AL on diabetic rats in vivo. The apoptotic index of cardiomyocytes was estimated by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. The expressions of Fas, Bcl-2, CTGF, and TGF-?(1) protein were studied by immunohistochemistry. Laser scanning confocal microscopy technique was utilized to observe the effects of AL on intracellular calcium concentration ([Ca(2+)](i)) in rat ventricular cardiomyocytes. AL at the doses of 4 mg/kg, 8 mg/kg, and 16 mg/kg significantly reduced blood glucose levels in a dose-dependent manner and increased body weight as well compared with the model group. Hemodynamic parameters including left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), and maximum rate of left ventricular pressure rise and fall (+dp/dtmax and -dp/dtmax) were significantly restored back to normal levels in AL-treated (8 mg/kg and 16 mg/kg) rats compared with diabetic model rats. AL markedly inhibited cardiomyocyte apoptosis induced by diabetic cardiac injury. Further investigation revealed that this inhibitory effect on cell apoptosis was mediated by increasing anti-apoptotic protein Bcl-2 and decreasing pro-apoptotic protein Fas. Additional experiments demonstrated AL abrogated myocardial fibrosis by blocking the expressions of CTGF and TGF-?(1) protein. AL shows protective action on myocardial injury in diabetic rats. The possible mechanisms were involved in reducing blood glucose, correcting hemodynamic impairment, reducing Fas expression, activating Bcl-2 expression, decreasing intracellular calcium overload, inhibiting the expressions of TGF-?(1) and CTGF, and further improving cardiac function. PMID:22633288

  3. Alleviation of hyperglycemia and hyperlipidemia by Phyllanthus virgatus forst extract and its partially purified fraction in streptozotocin induced diabetic rats

    PubMed Central

    Hashim, Arshya; Khan, M. Salman; Ahmad, Saheem

    2014-01-01

    Since, we previously demonstrated that sequentially extracted methanolic fraction showed marked antioxidant and antidiabetic property in vitro, the present study was design to evaluate the beneficial effects of Phyllanthus virgatus methanolic extract and its partially purified fraction on hyperglycemia and hyperlipidemia in streptozotocin (STZ) induced diabetic rats. The plant extract was subjected to repeated thin layer chromatographic fractionation followed by GC-MS analysis of active fraction. TLC data illustrated the presence of six prominent bands and the prelimnary screening of these bands against α-amylase inhibitory activity showed that the band with Rf value 0.514 has marked inhibitory property (IC50, 48 µg/ml). The diabetic rats were treated for four weeks with methanolic extract of P. virgatus (50 and 10 mg/rat/day), partially isolated active fraction (0.5 and 0.1 mg/rat/day) and glibenclamide (0.1 mg/rat/day). The level of fasting blood glucose (FBG), hemoglobin, glycated hemoglobin (HbA1c) and insulin were significantly alleviated in plant extract and partially purified fraction treated group after 28 days of administration. Moreover, total cholesterol (TC), triglycerides (TG), low density lipoprotein-cholesterol (LDL-C), very low density lipoprotein-cholesterol (VLDL-C) and high density lipoprotein cholesterol (HDL-C) were also markedly ameliorated in the entire treatment group, with a maximum restoration observed in group treated with partially purified fraction (0.5 mg/rat/day). The results demonstrate a strong antidiabetic and hypolipidemic impact of plant extract and its partially purified fraction coupled with their potent antioxidative property, which can provide additional benefits in the inhibition of oxidative stress and hence in the prevention and treatment of diabetes as well as diabetes linked hyperlipidemia. PMID:26417304

  4. Curcumin modulates dopaminergic receptor, CREB and phospholipase c gene expression in the cerebral cortex and cerebellum of streptozotocin induced diabetic rats

    PubMed Central

    2010-01-01

    Curcumin, an active principle component in rhizome of Curcuma longa, has proved its merit for diabetes through its anti-oxidative and anti-inflammatory properties. This study aims at evaluating the effect of curcumin in modulating the altered dopaminergic receptors, CREB and phospholipase C in the cerebral cortex and cerebellum of STZ induced diabetic rats. Radioreceptor binding assays and gene expression was done in the cerebral cortex and cerebellum of male Wistar rats using specific ligands and probes. Total dopaminergic receptor binding parameter, Bmax showed an increase in cerebral cortex and decrease in the cerebellum of diabetic rats. Gene expression studies using real time PCR showed an increased expression of dopamine D1 and D2 receptor in the cerebral cortex of diabetic rats. In cerebellum dopamine D1 receptor was down regulated and D2 receptor showed an up regulation. Transcription factor CREB and phospholipase C showed a significant down regulation in cerebral cortex and cerebellum of diabetic rats. We report that curcumin supplementation reduces diabetes induced alteration of dopamine D1, D2 receptors, transcription factor CREB and phospholipase C to near control. Our results indicate that curcumin has a potential to regulate diabetes induced malfunctions of dopaminergic signalling, CREB and Phospholipase C expression in cerebral cortex and cerebellum and thereby improving the cognitive and emotional functions associated with these regions. Furthermore, in line with these studies an interaction between curcumin and dopaminergic receptors, CREB and phospholipase C is suggested, which attenuates the cortical and cerebellar dysfunction in diabetes. These results suggest that curcumin holds promise as an agent to prevent or treat CNS complications in diabetes. PMID:20513244

  5. Puerarin attenuates learning and memory impairments and inhibits oxidative stress in STZ-induced SAD mice.

    PubMed

    Zhao, Shan-Shan; Yang, Wei-Na; Jin, Hui; Ma, Kai-Ge; Feng, Gai-Feng

    2015-12-01

    Puerarin (PUE), an isoflavone purified from the root of Pueraria lobata (Chinese herb), has been reported to attenuate learning and memory impairments in the transgenic mouse model of Alzheimer's disease (AD). In the present study, we tested PUE in a sporadic AD (SAD) mouse model which was induced by the intracerebroventricular injection of streptozotocin (STZ). The mice were administrated PUE (25, 50, or 100mg/kg/d) for 28 days. Learning and memory abilities were assessed by the Morris water maze test. After behavioral test, the biochemical parameters of oxidative stress (glutathione peroxidase (GSH-Px), superoxide dismutases (SOD), and malondialdehyde (MDA)) were measured in the cerebral cortex and hippocampus. The SAD mice exhibited significantly decreased learning and memory ability, while PUE attenuated these impairments. The activities of GSH-Px and SOD were decreased while MDA was increased in the SAD animals. After PUE treatment, the activities of GSH-Px and SOD were elevated, and the level of MDA was decreased. The middle dose PUE was more effective than others. These results indicate that PUE attenuates learning and memory impairments and inhibits oxidative stress in STZ-induced SAD mice. PUE may be a promising therapeutic agent for SAD. PMID:26511841

  6. Insulin administration abrogates perturbation of methyl group and homocysteine metabolism in streptozotocin-treated type 1 diabetic rats.

    PubMed

    Nieman, Kristin M; Schalinske, Kevin L

    2011-09-01

    Modifications in methyl group and homocysteine metabolism are associated with a number of pathologies, including vascular disease, cancer, and neural tube defects. A diabetic state is known to alter both methyl group and homocysteine metabolism, and glycine N-methyltransferase (GNMT) is a major regulatory protein that controls the supply and utilization of methyl groups. We have shown previously that diabetes induces GNMT expression and reduces plasma homocysteine pools by stimulating both its catabolism and folate-independent remethylation. This study was conducted to determine whether insulin plays a role in the control of homocysteine concentrations and GNMT as well as other key regulatory proteins. Male Sprague-Dawley rats were randomly assigned to one of three groups: control, streptozotocin (STZ)-induced diabetic (60 mg/kg body wt), and insulin-treated diabetic (1.0 U bid). After 5 days, rats were anesthetized (ketamine-xylazine) for procurement of blood and tissues. A 1.5-fold elevation in hepatic GNMT activity and hypohomocysteinemia in diabetic rats was completely prevented by insulin treatment. Additionally, diabetes-mediated alterations in methionine synthase, phosphatidylethanolamine N-methyltransferase, and DNA methylation were also prevented by insulin. We hypothesize that the concentration of blood glucose may represent a regulatory signal to modify GNMT and homocysteine. In support of this, blood glucose concentrations were negatively correlated with total plasma homocysteine (r = -0.75, P < 0.001) and positively correlated with GNMT activity (r = 0.77, P < 0.001). Future research will focus on further elucidating the role of glucose or insulin as a signal for regulating homocysteine and methyl group metabolism. PMID:21730260

  7. Astragalus prevents diabetic rats from developing cardiomyopathy by downregulating angiotensin II type2 receptors' expression.

    PubMed

    Li, Changyun; Cao, Linsheng; Zeng, Qiutang

    2004-01-01

    This study examined the potential roles of astragalus and angiotensin II type 2 receptor (AT2) in rats with streptozotocin (STZ)-induced diabetic cardiomyopathy. Of 52 female 4-week-old Wistar rats treated with high glucose and lipid diet to induce insulin resistance, 7 treated with sodium citrate buffer (pH=4.5) served as controls (con1) and the other 45 were treated by intraperitoneal injection (ip) of STZ to induce type 2 diabetes. After 20 weeks, the maximal velocity decrease of pressure per second in left ventricle within the period of isovolumic relaxation (-dp/dtmax) was detected by inserting cannula through right carotid artery. Of the 45 rats, 24 with -dp/dtmax < or = 700 mmHg/s (1 mmHg=0.133 kPa) developing diabetic cardiomyopathy were grouped as follows: 7 treated with double distilled H2O (ip) were included in control group 2 (con2); other 8 treated with AT2 agonist (CGP42112A, ip) were included in experimental group1 (exp); 9 treated with astragalus (po) constituted experimental group 2 (exp2). All injections lasted 4 weeks (qd) and the heart weight (HW) was recorded. Cardiomyocyte apoptosis index (CAI), mRNA of AT2 and Bcl-2 as well as AT2 and Bcl-2 protein values in cardiomyocytes were also measured. Our results showed that -dp/dtmax in exp1, exp2 and con2 were much lower than those in con1 (P<0.01). CAI and AT2 in both mRNA and protein in con1 were lower than those in the other three groups (P<0.01). The three parameters above were higher in exp1 but less in exp2 than those in con2, respectively (P<0.01). The three parameters and HW in exp1 were much higher than those in exp2 (P<0.01). Changes of Bcl-2 were opposite to those of AT2. Our results suggested that high expression of AT2 might accelerate the apoptosis of cardiomyocytes in diabetic rats and play an important role in precipitating diabetic cardiomyopathy and astragalus protects diabetic rats from developing cardiomyopathy by downregulating AT2. PMID:15587404

  8. Caffeic acid phenethyl amide improves glucose homeostasis and attenuates the progression of vascular dysfunction in Streptozotocin-induced diabetic rats

    PubMed Central

    2013-01-01

    Background Glucose intolerance and cardiovascular complications are major symptoms in patients with diabetes. Many therapies have proven beneficial in treating diabetes in animals by protecting the cardiovascular system and increasing glucose utilization. In this study, we evaluated the effects of caffeic acid phenethyl amide (CAPA) on glucose homeostasis and vascular function in streptozotocin (STZ)-induced type 1 diabetic rats. Methods Diabetes (blood glucose levels > 350 mg/dL), was induced in Wistar rats by a single intravenous injection of 60 mg/kg STZ. Hypoglycemic effects were then assessed in normal and type 1 diabetic rats. In addition, coronary blood flow in Langendorff-perfused hearts was evaluated in the presence or absence of nitric oxide synthase (NOS) inhibitor. The thoracic aorta was used to measure vascular response to phenylephrine. Finally, the effect of chronic treatment of CAPA and insulin on coronary artery flow and vascular response to phenylephrine were analyzed in diabetic rats. Results Oral administration of 0.1 mg/kg CAPA decreased plasma glucose in normal (32.9 2.3% decrease, P < 0.05) and diabetic rats (11.8 5.5% decrease, P < 0.05). In normal and diabetic rat hearts, 110 ?M CAPA increased coronary flow rate, and this increase was abolished by 10 ?M NOS inhibitor. In the thoracic aorta, the concentration/response curve of phenylephrine was right-shifted by administration of 100 ?M CAPA. Coronary flow rate was reduced to 7.2 0.2 mL/min at 8 weeks after STZ-induction. However, 4 weeks of treatment with CAPA (3 mg/kg, intraperitoneal, twice daily) started at 4 weeks after STZ induction increased flow rate to 11.2 0.5 mL/min (P < 0.05). In addition, the contractile response induced by 1 ?M phenylephrine increased from 6.8 0.6 mN to 11.4 0.4 mN (P < 0.05) and 14.9 1.4 mN (P < 0.05) by insulin (1 IU/kg, intraperitoneal) or CAPA treatment, respectively. Conclusions CAPA induced hypoglycemic activity, increased coronary blood flow and vascular response to phenylephrine in type 1 diabetic rats. The increase in coronary blood flow may result from endothelial NOS activation. However, the detailed cellular mechanisms need to be further evaluated. PMID:23829275

  9. Antidiabetic effect of S-allylcysteine: Effect on plasma and tissue glycoproteins in experimental diabetes.

    PubMed

    Saravanan, G; Ponmurugan, P; Senthil Kumar, G P; Rajarajan, T

    2010-12-01

    The present study was conducted to investigate the effect of S-allylcysteine (SAC) on dearrangement in glycoprotein levels in the streptozotocin induced diabetic model. SAC (150 mg/kg b.w./day) was administered orally for 45 days to normal and diabetic rats. STZ-induced diabetic rats showed significant increase in blood glucose and glycoprotein components such as hexose, hexosamine, fucose and sialic acid in plasma, liver and kidneys of diabetic rats. Oral administration of SAC to diabetic rats for a period of 45 days normalized all the above-mentioned biochemical parameters. The antihyperglycemic effect of SAC was compared with glyclazide, a well-known antihyperglycemic drug. The present study indicates that SAC possesses a significantly beneficial effect on the glycoprotein moiety in addition to its antidiabetic effect. PMID:20576413

  10. Diabetes induces compositional, structural and functional alterations on rat skeletal soleus muscle revealed by FTIR spectroscopy: a comparative study with EDL muscle.

    PubMed

    Bozkurt, Ozlem; Severcan, Mete; Severcan, Feride

    2010-12-01

    Diabetes Mellitus (DM) is a metabolic disorder, characterized by abnormally high blood glucose levels due to decreased secretion or effectiveness in function of insulin. Having a role in carbohydrate and lipid metabolism, skeletal muscle is affected by the absence of insulin in diabetic conditions. This current study reports the application of Fourier transform infrared (FTIR) spectroscopy in the determination of macromolecular alterations in streptozotocin (STZ)-induced diabetic rat skeletal Soleus (SOL) muscles, which highlight the promise of this technique in medical research. The results revealed that DM induced several alterations in macromolecular content and structure of slow-contracting SOL muscles. In diabetic SOL muscles, a decrease in the content of lipids, proteins and nucleic acids together with an increase in lipid order was observed. The decrease in the level of unsaturation and acyl chain length of lipids demonstrated the increased lipid peroxidation in DM. There were alterations in protein secondary structure in DM with a decrease in ?-helix and ?-sheet content of proteins, whereas the content of aggregated ?-strands increased, which is generally seen when proteins denature. Besides, the integrity of collagen molecules was found to be decreased, demonstrating the alterations in its triple helical structure in diabetic muscles. Furthermore, the same alterations mentioned above were also observed in diabetic fast-contracting Extensor Digitorum Longus (EDL) muscles. However, having a high content of mitochondria and relying on an oxidative pathway, SOL muscle was found to be more affected by DM. PMID:20967384

  11. Modulatory effects of Aloe vera leaf gel extract on oxidative stress in rats treated with streptozotocin.

    PubMed

    Rajasekaran, S; Sivagnanam, K; Subramanian, S

    2005-02-01

    Oxidative stress is currently suggested as a mechanism underlying diabetes and diabetic-related complications. Oxidative stress results from an imbalance between radical-generating and radical-scavenging systems. Many secondary plant metabolites have been reported to possess antioxidant activity. This study was designed to evaluate the potential antioxidative activity of the ethanolic extract from Aloe vera leaf gel in the plasma and pancreas of streptozotocin (STZ)-induced diabetic rats. Glibenclamide was used as a standard reference drug. Oral administration of ethanolic extract at a concentration of 300 mg kg(-1) body weight for 21 days resulted in a significant reduction in fasting blood glucose, thiobarbituric acid reactive substances, hydroperoxides and alpha-tocopherol and significant improvement in ascorbic acid, reduced glutathione and insulin in the plasma of diabetic rats. Similarly, the treatment also resulted in a significant reduction in thiobarbituric acid reactive substances, hydroperoxides, superoxide dismutase, catalase and glutathione peroxidase and significant improvement in reduced glutathione in the pancreas of STZ-induced diabetic rats when compared with untreated diabetic rats. The ethanolic extract appeared to be more effective than glibenclamide in controlling oxidative stress. Thus, this study confirms the ethnopharmacological use of Aloe vera in ameliorating the oxidative stress found in diabetes. PMID:15720789

  12. Effect of Hydroalcoholic and Buthanolic Extract of Cucumis sativus Seeds on Blood Glucose Level of Normal and Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Minaiyan, Mohsen; Zolfaghari, Behzad; Kamal, Amin

    2011-01-01

    Objective(s) Seed of Cucumis sativus Linn. is one of the herbal remedies has been traditionally used for diabetes mellitus treatment. We studied the effect of hydroalcoholic and buthanolic extract obtained from C. sativus seeds in a model of streptozotocin (STZ)-induced diabetic (type I) rats. Materials and Methods Normal and diabetic male Wistar rats (STZ, 60 mg/kg, intraperitoneal) were treated daily with vehicle (5 ml/kg), hydroalcoholic (0.2, 0.4, 0.8 g/kg) and buthanolic extract (0.2, 0.4, 0.8 g/kg) and glibenclamide (1 & 3 mg/kg) separately and treatment was continued for 9 days. Blood samples were taken at 0, 1, 2, 3, 4, 8 hr of the first day and the day 9 (216 hr) of treatments for measuring the blood glucose levels. Results Our findings indicated that C. sativus seeds extracts were not effective on reducing blood glucose levels (BGL) in normal and diabetic rats for initial phase of treatments. However, both hydroalcoholic (22.5-33.8 %) and buthanolic (26.6- 45.0 %) extracts were effective on diminishing BGL and controling the loss of body weight in diabetic rats compared to controls after 9 days of continued daily therapy. Glibenclamide on the other hand, had hypoglycemic action in normal (27.8-31.0 %) and diabetic rats (36.0-50.0 %) after acute and prolonged treatments. Conclusion It is concluded that C. sativus seeds extracts (hydroalcoholic and buthanolic) had a role in diabetes control probably through a mechanism similar to euglycemic agents. Further studies are warranted to clarify the mechanisms and the exact role of this herbal medicine in control of metabolic disorders. PMID:23493930

  13. Antihyperglycemic effect of thymoquinone and oleuropein, on streptozotocin-induced diabetes mellitus in experimental animals

    PubMed Central

    Sangi, Sibghatullah Muhammad Ali; Sulaiman, Mansour Ibrahim; El-wahab, Mohammed Fawzy Abd; Ahmedani, Elsamoual Ibrahim; Ali, Soad Shaker

    2015-01-01

    Background: Diabetes mellitus is one of the most important diseases related with endocrines. Its main manifestation includes abnormal metabolism of carbohydrates and lipids and inappropriate hyperglycemia that is caused by absolute or relative insulin deficiency. It affects humankind worldwide. Objectives: Our research was aimed to observe antihyperglycemic activity of thymoquinone and oleuropein. Materials and Methods: In this study, rats were divided into six groups, 6 rats in each. Diabetes was inducted by streptozotocin (STZ). The level of fasting blood glucose was determined for each rats during the experiment, doses of thymoquinone and oleuropein (3 mg/kg and 5 mg/kg) for both, were injected intraperitoneal. Pancreatic tissues were investigated to compare β-cells in diabetic and treated rats. Result and Conclusion: It was found that thymoquinone and oleuropein significantly decrease serum Glucose levels in STZ induced diabetic rats. PMID:26664013

  14. Betaine inhibits vascularization via suppression of Akt in the retinas of streptozotocin-induced hyperglycemic rats

    PubMed Central

    KIM, YOUNG-GIUN; LIM, HYUNG-HO; LEE, SUH-HA; SHIN, MAL-SOON; KIM, CHANG-JU; YANG, HYEON JEONG

    2015-01-01

    Diabetic retinopathy is a severe microvascular complication amongst patients with diabetes, and is the primary cause of visual loss through neovascularization. Betaine is one of the components of Fructus Lycii. In the present study, the effects of betaine on the expression levels of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor (HIF)-1α in association with the Akt pathway were investigated in the retinas of streptozotocin (STZ)-induced diabetic rats using western blot and immunohistochemical analyses. The results of the present study revealed that the expression levels of VEGF, HIF-1α, and Akt were increased in the retinas of the STZ-induced diabetic rats. Betaine treatment attenuated this increase in VEGF and HIF-1α expression via suppression of diabetes-induced Akt activation in the retinas of the diabetic rats. The results suggested that betaine may potentially be used to delay the onset of complications associated with diabetic retinopathy via inhibition of retinal neovascularization in patients with diabetes. PMID:25891515

  15. Streptozotocin-Induced Early Thermal Hyperalgesia is independent of Glycemic State of Rats: Role of Transient Receptor Potential Vanilloid 1(TRPV1) and Inflammatory mediators

    PubMed Central

    2011-01-01

    Background Streptozotocin (STZ) is used as a common tool to induce diabetes and to study diabetes-induced complications including diabetic peripheral neuropathy (DPN). Previously, we have reported that STZ induces a direct effect on neurons through expression and function of the Transient receptor potential vanilloid 1 (TRPV1) channel in sensory neurons resulting in thermal hyperalgesia, even in non-diabetic STZ-treated mice. In the present study, we investigated the role of expression and function of TRPV1 in the central sensory nerve terminals in the spinal cord in STZ-induced hyperalgesia in rats. Results We found that a proportion of STZ-treated rats were normoglycemic but still exhibited thermal hyperalgesia and mechanical allodynia. Immunohistochemical data show that STZ treatment, irrespective of glycemic state of the animal, caused microglial activation and increased expression of TRPV1 in spinal dorsal horn. Further, there was a significant increase in the levels of pro-inflammatory mediators (IL-1?, IL-6 and TNF-?) in spinal cord tissue, irrespective of the glycemic state. Capsaicin-stimulated release of calcitonin gene related peptide (CGRP) was significantly higher in the spinal cord of STZ-treated animals. Intrathecal administration of resiniferatoxin (RTX), a potent TRPV1 agonist, significantly attenuated STZ-induced thermal hyperalgesia, but not mechanical allodynia. RTX treatment also prevented the increase in TRPV1-mediated neuropeptide release in the spinal cord tissue. Conclusions From these results, it is concluded that TRPV1 is an integral component of initiating and maintaining inflammatory thermal hyperalgesia, which can be alleviated by intrathecal administration of RTX. Further, the results suggest that enhanced expression and inflammation-induced sensitization of TRPV1 at the spinal cord may play a role in central sensitization in STZ-induced neuropathy. PMID:21794120

  16. Effect of Solanum surattense on mitochondrial enzymes in diabetic rats and in vitro glucose uptake activity in L6 myotubes

    PubMed Central

    Sridevi, Muruhan; Kalaiarasi, Pannerselvam; Pugalendi, Kodukkur Viswanathan

    2015-01-01

    Background: S. surattense is widely used in Siddha medicine for various ailments. Objective: The aim was to evaluate the impact of alcoholic leaf-extract of S. surattense on mitochondrial enzymes in streptozotocin (STZ) induced diabetic rats and to study the in vitro muscle glucose uptake activity on L6 myotubes. Materials and Methods: The male albino Wistar rats were randomly divided into five groups of six animals each. Diabetes was induced by intraperitoneal injection of STZ (40 mg/kg body weight). After being confirmed the diabetic rats were treated with alcoholic leaf-extract of S. surattense (100 mg/kg body weight) for 45 days. The biochemical estimations (liver mitochondrial enzymes, antioxidants, thiobarbituric acid reactive substances [TBARS]) and histopathological studies were performed. Further, the in vitro muscle glucose uptake activity in L6 myotubes and messenger RNA (mRNA) expression of glucose transporter-4 (GLUT-4) was performed. Results: In diabetic rats, the activities of liver mitochondrial enzymes were found to be significantly lowered. The mitochondrial TBARS level increased, whereas the activities/level of enzymatic and non-enzymatic antioxidants decreased in diabetic rats. Administration of S. surattense to diabetic rats significantly reversed the above parameters toward normalcy. Furthermore in diabetic rats, the histopathological studies showed growth of adipose tissue and shrinkage of islets in the pancreas, liver showed fatty change with mild inflammation of portal triad, and kidney showed messangial capillary proliferation of glomeruli and fatty infiltration of tubules. Treatment with S. surattense brought back these changes to near normalcy. The extract was analyzed for in vitro muscle glucose uptake activity in L6 myotubes and mRNA expression of GLUT-4 by semi-quantitative reverse transcriptase-polymerase chain reaction. One nano gram per millilitre of S. surattense leaf-extract gave 115% glucose uptake on L6 myotubes. It also showed elevated levels of GLUT-4 mRNA transcripts, when compared with control cells. Conclusion: These studies strongly support the anti-diabetic nature of S. surattense. PMID:26834425

  17. Diabetic complications in obese type 2 diabetic rat models.

    PubMed

    Katsuda, Yoshiaki; Ohta, Takeshi; Miyajima, Katsuhiro; Kemmochi, Yusuke; Sasase, Tomohiko; Tong, Bin; Shinohara, Masami; Yamada, Takahisa

    2014-01-01

    We overviewed the pathophysiological features of diabetes and its complications in obese type 2 diabetic rat models: Otsuka Long-Evans Tokushima fatty (OLETF) rat, Wistar fatty rat, Zucker diabetic fatty (ZDF) rat and Spontaneously diabetic Torii (SDT) fatty rat. Pancreatic changes with progression of diabetes were classified into early changes, such as islet hypertrophy and degranulation of ? cells, and degenerative changes, such as islet atrophy and fibrosis of islet with infiltration of inflammatory cells. Renal lesions in tubuli and glomeruli were observed, and nodular lesions in glomeruli were notable changes in OLETF and SDT fatty rats. Among retinal changes, folding and thickening were interesting findings in SDT fatty rats. A decrease of motor nerve conduction velocity with progression of diabetes was presented in obese diabetic rats. Other diabetic complications, osteoporosis and sexual dysfunction, were also observed. Observation of bone metabolic abnormalities, including decrease of osteogenesis and bone mineral density, and sexual dysfunction, including hypotestosteronemia and erectile dysfunction, in obese type 2 diabetic rats have been reported. PMID:24770637

  18. The cardioprotective effect of an aqueous extract of fermented rooibos (Aspalathus linearis) on cultured cardiomyocytes derived from diabetic rats.

    PubMed

    Dludla, P V; Muller, C J F; Louw, J; Joubert, E; Salie, R; Opoku, A R; Johnson, R

    2014-04-15

    Diabetic cardiomyopathy (DCM) is a disorder of the heart muscle that contributes to cardiovascular deaths in the diabetic population. Excessive generation of free radicals has been directly implicated in the pathogenesis of DCM. The use of antioxidants, through dietary supplementation, to combat increased cellular oxidative stress has gained popularity worldwide. Aspalathus linearis (rooibos) is a popular herbal tea that contains a novel antioxidant, aspalathin. Literature has reported on the antidiabetic, anti-inflammatory and free radical scavenging effects of rooibos. However, its protective effect against DCM has not been established. Therefore, this study investigated whether chronic exposure to an aqueous extract of fermented rooibos (FRE) has an ex vivo cardioprotective effect on hearts obtained from streptozotocin (STZ) induced diabetic rats. Adult Wistar rats were injected with 40 mg/kg of STZ. Two weeks after STZ injection, cardiomyocytes were isolated and cultured. Cultured cardiomyocytes were treated with FRE (1 and 10 ?g/ml), vitamin E (50 ?g/ml), and n-acetyl cysteine (1mM) for 6h, before exposure to either hydrogen peroxide (H2O2) or an ischemic solution. Cardiomyocytes exposed to H2O2 or an ischemic solution showed a decrease in metabolic activity and glutathione content with a concomitant increase in apoptosis and intracellular reactive oxygen species. Pretreatment with FRE was able to combat these effects and the observed amelioration was better than the known antioxidant vitamin E. This study provides evidence that an aqueous extract of fermented rooibos protects cardiomyocytes, derived from diabetic rats, against experimentally induced oxidative stress and ischemia. PMID:24268738

  19. Neuromodulatory effects of hesperidin in mitigating oxidative stress in streptozotocin induced diabetes.

    PubMed

    Ashafaq, Mohammad; Varshney, Laxmi; Khan, Mohammad Haaris Ajmal; Salman, Mohd; Naseem, Mehar; Wajid, Saima; Parvez, Suhel

    2014-01-01

    Oxidative stress has been implicated in pathogenesis of streptozotocin- (STZ-) induced diabetes mellitus and its complication in central nervous system (CNS). Recent studies have provided insights on antioxidants and their emergence as potential therapeutic and nutraceutical. The present study examined the hypothesis that hesperidin (HP) ameliorates oxidative stress and may be a limiting factor in the extent of CNS complication following diabetes. To test this hypothesis rats were divided into four groups: control, diabetic, diabetic-HP treated, and vehicle for HP treatment group. Diabetes mellitus was induced by a single injection of STZ (65 mg/kg body weight). Three days after STZ injection, HP was given (50 mg/kg b.wt. orally) once daily for four weeks. The results of the present investigation suggest that the significant elevated levels of oxidative stress markers were observed in STZ-treated animals, whereas significant depletion in the activity of nonenzymatic antioxidants and enzymatic antioxidants was witnessed in diabetic rat brain. Neurotoxicity biomarker activity was also altered significantly. HP treatment significantly attenuated the altered levels of oxidative stress and neurotoxicity biomarkers. Our results demonstrate that HP exhibits potent antioxidant and neuroprotective effects on the brain tissue against the diabetic oxidative damage in STZ-induced rodent model. PMID:25050332

  20. Neuromodulatory Effects of Hesperidin in Mitigating Oxidative Stress in Streptozotocin Induced Diabetes

    PubMed Central

    Varshney, Laxmi; Khan, Mohammad Haaris Ajmal; Salman, Mohd.; Naseem, Mehar; Wajid, Saima

    2014-01-01

    Oxidative stress has been implicated in pathogenesis of streptozotocin- (STZ-) induced diabetes mellitus and its complication in central nervous system (CNS). Recent studies have provided insights on antioxidants and their emergence as potential therapeutic and nutraceutical. The present study examined the hypothesis that hesperidin (HP) ameliorates oxidative stress and may be a limiting factor in the extent of CNS complication following diabetes. To test this hypothesis rats were divided into four groups: control, diabetic, diabetic-HP treated, and vehicle for HP treatment group. Diabetes mellitus was induced by a single injection of STZ (65 mg/kg body weight). Three days after STZ injection, HP was given (50 mg/kg b.wt. orally) once daily for four weeks. The results of the present investigation suggest that the significant elevated levels of oxidative stress markers were observed in STZ-treated animals, whereas significant depletion in the activity of nonenzymatic antioxidants and enzymatic antioxidants was witnessed in diabetic rat brain. Neurotoxicity biomarker activity was also altered significantly. HP treatment significantly attenuated the altered levels of oxidative stress and neurotoxicity biomarkers. Our results demonstrate that HP exhibits potent antioxidant and neuroprotective effects on the brain tissue against the diabetic oxidative damage in STZ-induced rodent model. PMID:25050332

  1. Reduced glomerular size selectivity in late streptozotocin-induced diabetes in rats: application of a distributed two-pore model

    PubMed Central

    Lubbad, Loay; Öberg, Carl M; Dhanasekaran, Subramanian; Nemmar, Abderrahim; Hammad, Fayez; Pathan, Javed Y; Rippe, Bengt; Bakoush, Omran

    2015-01-01

    Microalbuminuria is an early manifestation of diabetic nephropathy. Potential contributors to this condition are reduced glomerular filtration barrier (GFB) size- and charge selectivity, and impaired tubular reabsorption of filtered proteins. However, it was recently reported that no significant alterations in charge selectivity of the GFB occur in early experimental diabetic nephropathy. We here aimed at investigating the functional changes in the GFB in long-term type-1 diabetes in rats, applying a novel distributed two-pore model. We examined glomerular permeability in 15 male Wistar rats with at least 3 months of streptozotocin (STZ)-induced diabetes (blood glucose ∼20 mmol/L) and in age-matched control rats. The changes in glomerular permeability were assessed by determining the glomerular sieving coefficients (θ) for FITC-Ficoll (molecular radius 20–90 Å) using size exclusion HPLC. The values of θ for FITC-Ficoll of radius >50 Å were significantly increased in STZ-diabetic rats compared to age-matched controls (θ for 50–69 Å = 0.001 vs. 0.0002, and θ for 70–90 Å = 0.0007 vs. 0.00006, P < 0.001), while θ for FITC-Ficoll <50 Å tended to be lower in diabetic rats than in controls (θ for 36–49 Å = 0.013 vs. 0.016, ns). According to the distributed two-pore model, there was primarily an increase in macromolecular transport through large pores in the glomerular filter of diabetic rats associated with a loss of small-pore area. Deterioration in the glomerular size selectivity due to an increase in the number and size-spread of large pores, with no changes in the permeability of the small-pore system, represent the major functional changes observed after 3 months of induced experimental diabetes. PMID:26009635

  2. Dapagliflozin reduces the amplitude of shortening and Ca(2+) transient in ventricular myocytes from streptozotocin-induced diabetic rats.

    PubMed

    Hamouda, N N; Sydorenko, V; Qureshi, M A; Alkaabi, J M; Oz, M; Howarth, F C

    2015-02-01

    In the management of type 2 diabetes mellitus, Dapagliflozin (DAPA) is a newly introduced selective sodium-glucose co-transporter 2 inhibitor which promotes renal glucose excretion. Little is known about the effects of DAPA on the electromechanical function of the heart. This study investigated the effects of DAPA on ventricular myocyte shortening and intracellular Ca(2+) transport in streptozotocin (STZ)-induced diabetic rats. Shortening, Ca(2+) transients, myofilament sensitivity to Ca(2+) and sarcoplasmic reticulum Ca(2+), and intracellular Ca(2+) current were measured in isolated rats ventricular myocytes by video edge detection, fluorescence photometry, and whole-cell patch-clamp techniques. Diabetes was characterized in STZ-treated rats by a fourfold increase in blood glucose (440 25 mg/dl, n = 21) compared to Controls (98 2 mg/dl, n = 19). DAPA reduced the amplitude of shortening in Control (76.68 2.28 %, n = 37) and STZ (76.58 1.89 %, n = 42) ventricular myocytes, and reduced the amplitude of the Ca(2+) transients in Control and STZ ventricular myocytes with greater effects in STZ (71.45 5.35 %, n = 16) myocytes compared to Controls (92.01 2.72 %, n = 17). Myofilament sensitivity to Ca(2+) and sarcoplasmic reticulum Ca(2+) were not significantly altered by DAPA in either STZ or Control myocytes. L-type Ca(2+) current was reduced in STZ myocytes compared to Controls and was further reduced by DAPA. In conclusion, alterations in the mechanism(s) of Ca(2+) transport may partly underlie the negative inotropic effects of DAPA in ventricular myocytes from STZ-treated and Control rats. PMID:25351341

  3. Anti-hyperglycaemic activity of swietenia macrophylla king (meliaceae) seed extracts in normoglycaemic rats undergoing glucose tolerance tests

    PubMed Central

    2013-01-01

    Background Swietenia macrophylla King (Meliaceae) is used to treat diabetes mellitus in Malaysia. This study aims to evaluate the anti-hyperglycaemic potential of petroleum ether (PE), chloroform (CE) and methanol (ME) extracts of S. macrophylla seeds, in normoglycaemic and streptozotocin (STZ)-induced diabetic rats. Methods Following treatment of normoglycaemic rats with S. macrophylla seed extracts, hypoglycaemic and intraperitoneal glucose tolerance tests (IPGTT) were performed, and blood glucose concentrations were measured. Similarly, glucose concentrations were measured after 1 and 14 days of extract treatment of STZ-induced diabetic rats. Glucose absorption by isolated everted intestine and glucose uptake by isolated abdominal muscle were tested after treatment with seed extracts. Gas chromatography mass spectrometry (GC-MS) analysis was performed on PE of S. macrophylla seeds to identify the compounds responsible for its activity. Results None of the extracts had a significant effect on the blood glucose levels of 60 randomly selected normoglycaemic (normal) and diabetic rats undergoing hypoglycaemic tests. PE, however, significantly reduced blood glucose levels in 30 randomly selected normoglycaemic rats undergoing IPGTT tests 30120 minutes after glucose administration. Repeated doses of 1000 mg/kg and 500 mg/kg PE to STZ-induced diabetic rats for 14 days did not reduce blood glucose levels significantly. PE did not significantly reduced the intestinal absorption of glucose, but significantly increased glucose uptake by abdominal muscle in the absence or presence of insulin. GC-MS analysis indicated that diterpenes, triterpenoids, fatty acid methyl esters, aldehydes and phytosterols may be responsible for the glucose lowering effects of PE. Conclusion PE extracts of S. macrophylla seeds showed anti-hyperglycaemic activity on IPGTTs . GC-MS analysis on the PE revealed that several compounds, including fucosterol and ?-sitosterol, may be responsible for these anti-hyperglycaemic properties. PMID:23684219

  4. Time dependent changes in the intestinal Ca? absorption in rats with type I diabetes mellitus are associated with alterations in the intestinal redox state.

    PubMed

    Rivoira, Mara; Rodrguez, Valeria; Lpez, Mara Peralta; Tolosa de Talamoni, Nori

    2015-03-01

    The aim was to determine the intestinal Ca? absorption in type I diabetic rats after different times of STZ induction, as well as the gene and protein expression of molecules involved in both the transcellular and paracellular Ca? pathways. The redox state and the antioxidant enzymes of the enterocytes were also evaluated in duodenum from either diabetic or insulin-treated diabetic rats as compared to control rats. Male Wistar rats (150-200 g) were divided into two groups: 1) controls and 2) STZ-induced diabetic rats (60 mg/kg b.w.). A group of diabetic rats received insulin for five days. The insulin was adjusted daily to maintain a normal blood glucose level. Five 5 d after STZ injection, there was a reduction in the intestinal Ca? absorption, which was maintained for 30 d and disappeared at 60 d. Similar changes occurred in the GSH and (?)O(2)(-) levels. The protein expression of molecules involved in the transcellular pathway increased at 5 and 30 d returning to control values at 60 d. Their mRNA levels declined considerably at 60 d. The gene and protein expression of claudin 2 was upregulated at 30 d. Catalase activity increased at 5 and 30 d normalizing at 60 d. To conclude, type I D.m. inhibits the intestinal Ca? absorption, which is transient leading to a time dependent adaptation and returning the absorptive process to normal values. The inhibition is accompanied by oxidative stress. When insulin is administered, the duodenal redox state returns to control values and the intestinal Ca? absorption normalizes. PMID:25459228

  5. Antidiabetic antihyperlipidemic and hepato-protective effect of Gluconorm-5: A polyherbal formulation in steptozotocin induced hyperglycemic rats

    PubMed Central

    Gengiah, Kalavathy; Hari, Rajeswary; Anbu, J.

    2014-01-01

    Background: The antidiabetic, antihyperlipidemic, and hepato-protective effect of Gluconorm-5, was studied in steptozotocin (STZ) induced hyperglycemic rats. Materials and Methods: The hypoglycemic effect of single dose of Gluconorm-5 (150, 300 and 600 mg/kg body weight) made up of five plants namely Camellia sinensis, Punica granatum, Macrotyloma uniflorum, Foeniculum vulgare and Trigonella foenum-graecum was studied in normal, glucose loaded normal and diabetes-induced rats. The extent of antihyperlipidemic and liver-protective effect was studied by estimating the lipid profile, and the liver marker enzymes. Histopathological studies of the pancreatic tissue were also carried out with glibenclamide as standard antihyperglycemic agent. Results: Fifteen days of oral feeding of the Gluconorm-5 (300 and 600 mg/kg) to diabetic rats resulted in a significant (P < 0.01) reduction of blood glucose, lipid profile, liver weight and marker enzymes as compared to those rats in whom STZ induced toxicity was untreated. The diabetic rats treated with the drug showed expanded islets as compared to the untreated diabetic rats, which showed the shrunken islets. The animals that received 300 mg/kg of Gluconorm-5 showed pronounced antidiabetic, antihyperlipidemic and hepato-protective effect in the present study, which was comparable with glibenclamide, a standard drug. Conclusion: Gluconorm-5 exerts potent antidiabetic antihyperlipidemic and hepato-protective effect, which can be used as adjuvant in the treatment of diabetes mellitus. PMID:25737607

  6. ?-cell regenerative efficacy of a polysaccharide isolated from methanolic extract of Tinospora cordifolia stem on streptozotocin -induced diabetic Wistar rats.

    PubMed

    Rajalakshmi, Manikkam; Anita, Roy

    2016-01-01

    The use of herbal supplements either as extracts or plant-derived individual molecules has significantly increased in the process of drug discovery and development for their potential efficacy or reduced risk in treating human disorders. Tinospora cordifolia (T. cordifolia) is a widely used herbal source to treat various human ailments, including diabetes mellitus. The present study was aimed on evaluating the antidiabetic property of a novel polysaccharide isolated from the methanolic extract of T. cordifolia stem. Bioassay guided fractionation was followed to isolate a compound from the methanol extract. The compound was administered orally at a dose of 20mg/kg.b.wt for 60 days to control and STZ-induced diabetic male Wistar rats. It was found that plasma glucose was significantly (p<0.05) reduced compared to normal. Oral administration of the compound significantly decreased HBA1c, triglycerides and total cholesterol and at the same time markedly increased hemoglobin, tissue glycogen and HDL cholesterol. Also the compounds restored the altered carbohydrate metabolizing enzymes, insulin, C-peptide, (14)C-glucose oxidation levels to near normal. In addition, the histological studies revealed that there was regeneration of ?-cells in the pancreatic sections. The expression of Glut-4 mRNA and protein in the gasrtocnemius muscle were significantly enhanced after the compound treatment. These results confirm that the novel polysaccharide possesses hypoglycemic, glucose oxidizing, hypolipidemic and ?-cell regenerative properties and hence it could be developed into potential oral hypoglycemic drug with lesser side effects. PMID:26616445

  7. Modulation of Adipocytokines Production and Serum NEFA Level by Metformin, Glimepiride, and Sitagliptin in HFD/STZ Diabetic Rats

    PubMed Central

    Saad, Mohamed I.; Kamel, Maher A.; Hanafi, Mervat Y.

    2015-01-01

    Type 2 diabetes mellitus (T2DM) is a group of metabolic disorders characterized by hyperglycemia owing to insulin resistance and/or insulin deficiency. Current theories of T2DM pathophysiology include a decline in β-cells function, a defect in insulin signaling pathways, and a dysregulation of secretory function of adipocytes. This study aimed to investigate the effect of different antidiabetic drugs on serum levels of certain adipocytokines and nonesterified fatty acids (NEFA) in high-fat diet (HFD)/streptozotocin- (STZ-) induced diabetic rats. All treatments significantly decreased serum NEFA level. Metformin and sitagliptin increased serum adiponectin level, whereas they decreased serum leptin level. Glimepiride showed significant decline in serum levels of both adiponectin and leptin. All treatments remarkably ameliorated insulin resistance, suggested by an improvement of glycemic control, a significant reduction in homeostasis model assessment of insulin resistance (HOMA-IR), and a correction in lipid profile. Modulation of adipocytokines production (i.e., increased serum adiponectin and decreased serum leptin) may also underlie the improvement of insulin resistance and could be a possible mechanism for the beneficial cardiovascular effects of metformin and sitagliptin. PMID:25838947

  8. Resveratrol Ameliorates Diabetes-Induced Cardiac Dysfunction Through AT1R-ERK/p38 MAPK Signaling Pathway.

    PubMed

    Gao, Yonglin; Kang, Le; Li, Chunmei; Wang, Xiaoyan; Sun, Chengfeng; Li, Qingzhong; Liu, Ruihua; Wang, Jianping

    2016-04-01

    The present study was to determine the preventive effect of resveratrol (Res) on diabetes-induced cardiac dysfunction and the possible signaling pathway involved. Diabetes was induced in rats by injection of streptozotocin (STZ) at 45 mg/kg. The animals were randomly divided into three groups (10 rats/group): normal group, diabetes groups with or without Res (80 mg/kg) treatment. Biochemistry, cardiac function and fibrosis were detected. Moreover, pro-inflammatory cytokines were evaluated, and heart tissues were homogenized for western blot analysis to analyze the possible mechanisms. The results indicated that Res might regulate glucose and lipid metabolism, ameliorate cardiac function and fibrosis response in STZ-induced diabetic rats. The protective effects were consistent with the inhibition of inflammatory factors such as TNF-α, IL-6 and IL-1β. In addition, Res favorably shifted STZ-induced AT1R, ERK1/2 and p38 MAPK activation in rat heart. In conclusion, the results suggested that Res attenuated diabetes-induced cardiac dysfunction, and the effects were associated with attenuation inflammatory response and down-regulation of AT1R-ERK/p38 MAPK signaling pathway. PMID:25800751

  9. Roles of the co-culture of human umbilical cord Wharton’s jelly-derived mesenchymal stem cells with rat pancreatic cells in the treatment of rats with diabetes mellitus

    PubMed Central

    WANG, GUANGYU; LI, YONG; WANG, YU; DONG, YU; WANG, FU-SHENG; DING, YI; KANG, YUDONG; XU, XUYING

    2014-01-01

    The aim of the present study was to investigate the roles of the co-culture of human umbilical cord Wharton’s jelly-derived mesenchymal stem cells (hUC-MSCs) with rat pancreatic cells in the treatment of rats with diabetes mellitus. hUC-MSCs were isolated and passaged, followed by Transwell co-culture with rat pancreatic cells. The induced islet-like cell clusters were transplanted into the renal capsule in rats with streptozotocin (STZ)-induced diabetes mellitus. The effects of co-culture on blood glucose levels in rats were observed. The isolated hUC-MSCs expressed the specific surface markers, including cluster of differentiation 44 (CD44) (91.4%), CD29 (91.3%) and CD105 (99.2%). Following co-culture with hUC-MSCs for 7 and 10 days, the rat pancreatic cells were strongly stained by pancreatic and duodenal homeobox-1 and human insulin. The insulin and C-peptide concentrations were increased significantly compared to the pure culture group. One week following the transplantation of induced islet-like cells into the renal capsule, the blood glucose level of rats in the STZ experimental group was significantly lower than that of the STZ control group. There were notable 5-bromo-2′-deoxyuridine-positive nuclei and insulin-positive cytoplasm in the renal capsule following cell transplantation. Therefore, co-culture of hUC-MSCs with rat pancreatic cells can lower the blood glucose levels in rats with diabetes mellitus. PMID:25289028

  10. Differential gene expression in pancreatic tissues of streptozocin-induced diabetic rats and genetically-diabetic mice in response to hypoglycemic dipeptide cyclo (His-Pro) treatment.

    PubMed

    Choi, Song Ah; Suh, Hyung Joo; Yun, Jong Won; Choi, Jang Won

    2012-09-01

    Diabetic studies are mostly interested in gene expression in the pancreas, the site of insulin secretion that regulates blood glucose levels. However, a single gene approach has been ruled out for many years in discovering new genes or the molecular networks involved in the induction process of diabetes. To understand the molecular mechanisms by which cyclo (His-Pro) (CHP) affects amelioration of diabetes mellitus, we performed gene expression profiling in the pancreatic tissues of two diabetic animal models, streptozocin (STZ)-induced diabetic rats (T1DM) and genetically-diabetic (C57BL/6J ob/ob) mice (T2DM). To understand the healing process of these diabetic rodents, we examined the effects of CHP on various gene expression in pancreatic tissues of both animal models. Our microarray analysis revealed that a total of 1,175 genes were down-regulated and 629 genes were up-regulated in response to STZ treatment, and the altered expression levels of numerous genes were restored to normal state upon CHP treatment. In particular, 476 genes showed significantly altered gene expression upon CHP treatment. In a functional classification, 7,198 genes were counted as differentially expressed in pancreatic tissues of STZ- and CHP-treated rats compared with control, whereas 1,534 genes were restored to normal states by CHP treatment. Microarray data demonstrated for the first time that overexpression of the genes encoding IL-1 receptor, lipid metabolic enzymes (e.g. Mte1, Ptdss1, and Sult2a1), myo-inositol oxygenase, glucagon, and somatostatin as well as down-regulation of olfactory receptor 984 and mitochondrial ribosomal protein, which are highly linked to T1DM etiology. In genetically-diabetic mice, 4,384 genes were altered in gene expression by more than 2-fold compared to the control mice, when counted differentially expressed. In genetically-diabetic mice, 4,384 genes altered in expression by higher than 2-fold were counted as differentially expressed genes in pancreatic tissues of CHP-treated mice. On the other hand, 2,140 genes were up-regulated and 2,244 genes were down-regulated by CHP treatment. The results of the microarray analysis revealed that up-regulation of IL-2, IL12a, and leptin receptor and down-regulation of PIK3 played important physiological roles in the onset of T2DM. In conclusion, we hypothesize that CHP accelerates alterations of gene expression in ameliorating diabetes and antagonizes those that induces the disease. PMID:22707198

  11. Therapeutic potential of some plant extracts used in Turkish traditional medicine on streptozocin-induced type 1 diabetes mellitus in rats.

    PubMed

    Ozkol, Halil; Tuluce, Yasin; Dilsiz, Nihat; Koyuncu, Ismail

    2013-01-01

    Diabetes mellitus (DM) is known to impair many physiological functions. Some reports claim that medicinal plants can reduce these alterations caused by DM. The aim of this study was to investigate the therapeutic potential of aqueous-methanol extracts of Urtica dioica, Thymus vulgaris (TV), Myrtus communis (MC), Scolymus hispanicus (SH) and Cinnamomun zeylanicum (CZ) on streptozotocin (STZ)-induced type 1 DM in rats. Diabetes was induced via a single i.p. injection of STZ (65 mg/kg body weight). After 1 week to allow for development of diabetes, each plant extract was administered to diabetic rats separately at a dose of 100 mg/kg body weight daily for 28 days. The results showed that only SH extract significantly (P < 0.05) amended fasting blood glucose level. The lipid profile was ameliorated especially by supplementations of TV, MC and CZ extracts. Almost all plant extract treatments markedly (P < 0.05) increased reduced glutathione content and decreased lipid peroxidation levels of erythrocyte, plasma, retina and lens tissues. They also significantly (P < 0.05) amended erythrocyte catalase activity, levels of marker serum enzymes (except amylase), urea and blood urea nitrogen when compared to diabetic rats treated with nothing. Furthermore, none of the plant extracts counteracted body weight loss of diabetic rats. Our data revealed that the aforementioned plant extracts have remarkable potential to counteract DM-caused alterations, probably through their antioxidant and free radical-defusing effects. PMID:23052826

  12. Beneficial effect of 17{beta}-estradiol on hyperglycemia and islet {beta}-cell functions in a streptozotocin-induced diabetic rat model

    SciTech Connect

    Yamabe, Noriko; Kang, Ki Sung; Zhu Baoting

    2010-11-15

    The modulating effect of estrogen on glucose homeostasis remains a controversial issue at present. In this study, we sought to determine the beneficial effect of 17{beta}-estradiol (E{sub 2}) on hyperglycemia and islet {beta}-cell functions in streptozotocin (STZ)-induced diabetic rats. Male Sprague-Dawley rats were injected i.p. with STZ to induce a relatively mild diabetic condition. The rats were then treated with E{sub 2} orally at 500 {mu}g/kg body weight/day for 15 days to evaluate the modulating effect on hyperglycemia, insulin secretion, and islet {beta}-cell proliferation. E{sub 2} administration for 10 days significantly lowered plasma glucose levels, increased plasma insulin levels, and improved glucose tolerance by attenuating insulin response to oral glucose loading. These beneficial effects of E{sub 2} were accompanied by increases in islet number and volume, rate of islet cell proliferation, and the amount of insulin secreted. The growth-stimulatory effect of E{sub 2} on islet cells was linked to the functions of the estrogen receptor {alpha}. Notably, these protective effects of E{sub 2} on diabetic conditions were basically not observed when the STZ-treated rats had a more severe degree of islet damage and hyperglycemia. Taken together, we conclude that E{sub 2} can promote the regeneration of damaged pancreatic islets by stimulating {beta}-cell proliferation in diabetic rats, and this effect is accompanied by improvements in glucose tolerance and a decrease in plasma glucose levels. These findings suggest that oral administration of E{sub 2} may be beneficial in diabetic patients with an accelerated loss of islet {beta}-cells.

  13. Mangiferin Attenuates Diabetic Nephropathy by Inhibiting Oxidative Stress Mediated Signaling Cascade, TNFα Related and Mitochondrial Dependent Apoptotic Pathways in Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Pal, Pabitra Bikash; Sinha, Krishnendu; Sil, Parames C.

    2014-01-01

    Oxidative stress plays a crucial role in the progression of diabetic nephropathy in hyperglycemic conditions. It has already been reported that mangiferin, a natural C-glucosyl xanthone and polyhydroxy polyphenol compound protects kidneys from diabetic nephropathy. However, little is known about the mechanism of its beneficial action in this pathophysiology. The present study, therefore, examines the detailed mechanism of the beneficial action of mangiferin on STZ-induced diabetic nephropathy in Wister rats as the working model. A significant increase in plasma glucose level, kidney to body weight ratio, glomerular hypertrophy and hydropic changes as well as enhanced nephrotoxicity related markers (BUN, plasma creatinine, uric acid and urinary albumin) were observed in the experimental animals. Furthermore, increased oxidative stress related parameters, increased ROS production and decreased the intracellular antioxidant defenses were detected in the kidney. Studies on the oxidative stress mediated signaling cascades in diabetic nephropathy demonstrated that PKC isoforms (PKCα, PKCβ and PKCε), MAPKs (p38, JNK and ERK1/2), transcription factor (NF-κB) and TGF-β1 pathways were involved in this pathophysiology. Besides, TNFα was released in this hyperglycemic condition, which in turn activated caspase 8, cleaved Bid to tBid and finally the mitochorndia-dependent apoptotic pathway. In addition, oxidative stress also disturbed the proapoptotic-antiapoptotic (Bax and Bcl-2) balance and activated mitochorndia-dependent apoptosis via caspase 9, caspase 3 and PARP cleavage. Mangiferin treatment, post to hyperglycemia, successfully inhibited all of these changes and protected the cells from apoptotic death. PMID:25233093

  14. Magnetic resonance imaging analysis of cardiac cycle events in diabetic rats: the effect of angiotensin-converting enzyme inhibition

    PubMed Central

    Al-Shafei, Ahmad I M; Wise, R G; Gresham, G A; Carpenter, T A; Hall, L D; Huang, Christopher L-H

    2002-01-01

    Non-invasive magnetic resonance imaging (MRI) was used to characterize changes in left and right ventricular cardiac cycles following induction of experimental, streptozotocin (STZ)-induced, diabetes in male Wistar rats at different ages. The effects of the angiotensin-converting enzyme (ACE) inhibitor captopril upon such chronic physiological changes were then evaluated, also for the first time. Diabetes was induced at the age of 7 weeks in two experimental groups, of which one group was subsequently maintained on captopril (2 g l?1)-containing drinking water, and at 10 and 13 weeks in two further groups. The fifth group provided age-matched controls. All groups (each n = 4 animals) were scanned consistently at 16 weeks, in parallel with timings used in earlier studies that employed this experimental model. Cine magnetic resonance (MR) image acquisition provided transverse sections through both ventricles at twelve time points covering systole and most of diastole. These yielded reconstructions of cardiac anatomy used to derive critical functional indices and their dependence upon time following the triggering electrocardiographic R waves. The left and right ventricular end-diastolic (EDV), end-systolic (ESV) and stroke volumes (SV), and ejection fractions (EF) calculated from each, control and experimental, group showed matching values. This confirmed a necessary condition requiring balanced right and left ventricular outputs and further suggested that STZ-induced diabetes produced physiological changes in both ventricles. Absolute left and right ventricular SVs were significantly altered in all diabetic animals; EDVs and EFs significantly altered in animals diabetic from 7 and 10 but not 13 weeks. When normalized to body weight, left and right ventricular SVs had significantly altered in animals diabetic from 7 and 10 weeks but not 13 weeks. Normalized left ventricular EDVs were also significantly altered in animals diabetic from 7 and 10 weeks. However, normalized right ventricular EDVs were significantly altered only in animals made diabetic from 7 weeks. Diabetic hearts showed major kinetic changes in left and right ventricular contraction (ejection) and relaxation (filling). Both the initial rates of volume change (dV/dt) in both ventricles and the plots of dV/dt values through the cardiac cycle demonstrated more gradual developments of tension during systole and relaxation during diastole. Estimates of the derived left ventricular performance parameters of cardiac output, cardiac power output and stroke work in control animals were comparable with human values when normalized to both body (or cardiac) weight and heart rate. All deteriorated with diabetes. Comparisons of experimental groups diabetic from 7 weeks demonstrated that captopril treatment relieved the alterations in critical volumes, dependence of SV upon EDV, kinetics of systolic contraction and diastolic relaxation and in the derived indicators of ventricular performance. This study represents the first demonstration using non-invasive MRI of early, chronic changes in diastolic filling and systolic ejection in both the left and the right ventricles and of their amelioration by ACE inhibition following STZ-induction of diabetes in intact experimental animals. PMID:11790819

  15. Magnetic resonance imaging analysis of cardiac cycle events in diabetic rats: the effect of angiotensin-converting enzyme inhibition.

    PubMed

    Al-Shafei, Ahmad I M; Wise, R G; Gresham, G A; Carpenter, T A; Hall, L D; Huang, Christopher L H

    2002-01-15

    Non-invasive magnetic resonance imaging (MRI) was used to characterize changes in left and right ventricular cardiac cycles following induction of experimental, streptozotocin (STZ)-induced, diabetes in male Wistar rats at different ages. The effects of the angiotensin-converting enzyme (ACE) inhibitor captopril upon such chronic physiological changes were then evaluated, also for the first time. Diabetes was induced at the age of 7 weeks in two experimental groups, of which one group was subsequently maintained on captopril (2 g l(-1))-containing drinking water, and at 10 and 13 weeks in two further groups. The fifth group provided age-matched controls. All groups (each n = 4 animals) were scanned consistently at 16 weeks, in parallel with timings used in earlier studies that employed this experimental model. Cine magnetic resonance (MR) image acquisition provided transverse sections through both ventricles at twelve time points covering systole and most of diastole. These yielded reconstructions of cardiac anatomy used to derive critical functional indices and their dependence upon time following the triggering electrocardiographic R waves. The left and right ventricular end-diastolic (EDV), end-systolic (ESV) and stroke volumes (SV), and ejection fractions (EF) calculated from each, control and experimental, group showed matching values. This confirmed a necessary condition requiring balanced right and left ventricular outputs and further suggested that STZ-induced diabetes produced physiological changes in both ventricles. Absolute left and right ventricular SVs were significantly altered in all diabetic animals; EDVs and EFs significantly altered in animals diabetic from 7 and 10 but not 13 weeks. When normalized to body weight, left and right ventricular SVs had significantly altered in animals diabetic from 7 and 10 weeks but not 13 weeks. Normalized left ventricular EDVs were also significantly altered in animals diabetic from 7 and 10 weeks. However, normalized right ventricular EDVs were significantly altered only in animals made diabetic from 7 weeks. Diabetic hearts showed major kinetic changes in left and right ventricular contraction (ejection) and relaxation (filling). Both the initial rates of volume change (dV/dt) in both ventricles and the plots of dV/dt values through the cardiac cycle demonstrated more gradual developments of tension during systole and relaxation during diastole. Estimates of the derived left ventricular performance parameters of cardiac output, cardiac power output and stroke work in control animals were comparable with human values when normalized to both body (or cardiac) weight and heart rate. All deteriorated with diabetes. Comparisons of experimental groups diabetic from 7 weeks demonstrated that captopril treatment relieved the alterations in critical volumes, dependence of SV upon EDV, kinetics of systolic contraction and diastolic relaxation and in the derived indicators of ventricular performance. This study represents the first demonstration using non-invasive MRI of early, chronic changes in diastolic filling and systolic ejection in both the left and the right ventricles and of their amelioration by ACE inhibition following STZ-induction of diabetes in intact experimental animals. PMID:11790819

  16. Smooth muscle myosin expression, isoform composition, and functional activities in rat corpus cavernosum altered by the streptozotocin-induced type 1 diabetes.

    PubMed

    Zhang, Xinhua; Kanika, Nirmala D; Melman, Arnold; DiSanto, Michael E

    2012-01-01

    Diabetes mellitus (DM) is a quite common chronic disease, and the prevalence of erectile dysfunction (ED) is three times higher in this large population. Although diabetes-related ED has been studied extensively, the actin-myosin contractile apparatus was not examined. The mRNAs encoding smooth muscle myosin (SMM) heavy chains (MHC) and essential light chains (LC(17)) exist as several different alternatively spliced isoforms with distinct contractile properties. Recently, we provided novel data that blebbistatin (BLEB), a specific myosin II inhibitor, potently relaxed corpus cavernosum smooth muscle (CCSM). In this study, we examine whether diabetes alters SMM expression, alternative splicing, and/or functional activities, including sensitivity to BLEB. By using streptozotocin (STZ)-induced 2-mo diabetic rats, functional activities were tested in vivo by intracavernous pressure (ICP) recording during cavernous nerve stimulation and in vitro via organ bath contractility studies. SMM isoform composition was analyzed by competitive RT-PCR and total SMM, myocardin, and embryonic SMM (SMemb) expression by real-time RT-PCR. Results revealed that the blood glucose level of STZ rats was 407.0 vs. 129.5 mg/dl (control). STZ rats exhibited ED confirmed by significantly increased CCSM contractile response to phenylephrine and decreased ICP response. For STZ rats, SM-B, LC(17a) and SM2 isoforms, total SMM, and myocardin expression increased, whereas SM-A, LC(17b), and SM1 isoforms were decreased, with SMemb unchanged. BLEB was significantly more effective in relaxing STZ CCSM both in vitro and in vivo. Thus we demonstrated a novel diabetes-specific effect on alternative splicing of the SMM heavy chain and essential light chain genes to a SMM isoform composition favoring a heightened contractility and ED. A switch to a more contractile phenotype was supported further by total SMM expression increase. Moreover, the change in CCSM phenotype was associated with an increased sensitivity to BLEB, which may serve as a novel pharmacotherapy for ED. PMID:21917637

  17. Preventive Effect of Garlic (Allium sativum L.) on Serum Biochemical Factors and Histopathology of Pancreas and Liver in Streptozotocin- Induced Diabetic Rats.

    PubMed

    Masjedi, Fatemeh; Gol, Ali; Dabiri, Shahriar

    2013-01-01

    Antidiabetic action of garlic is established in animal studies. Since all of the pervious studies have focused on the therapeutic role of garlic, this study investigated the preventive effect of garlic juice on biochemical factors and histological features in Streptozotocin (STZ)- induced diabetic rats. Forty male rats were divided into five groups (n = 8): 1-Normal group (N), 2-Normal+Garlic group (N+G) received garlic juice (1 mL/100g BW) for 6 weeks, 3-Diabetic group (D) was injected with STZ (60 mg/kg, IP), 4-Diabetic+Garlic-before group (D+Gb) received garlic juice for 3 weeks before STZ injection and continued for another 3 weeks, 5-Diabetic+Garlic-after group (D+Ga), three days after STZ injection, they received garlic juice for 3 weeks. Serum biochemical factors were measured by the enzymatic methods and H&E stained sections of pancreas and liver were prepared for light microscopy. In diabetic rats, elevated levels of glucose, cholesterol and triglycerides, the increment of the activities of ALT and AST, increased food and water consumption were observed. The abnormal increases were significantly (p < 0.05) decreased in D+Gb groups compared to D group. In D group, scattered degeneration of the hepatocytes with lymphocytic infiltration in the portal areas, decrease of pancreatic islets numbers and diameter, atrophy of pancreatic islets were observed. These abnormal histological signs were dramatically ameliorated in D+Gb group compared to D group. In D+Ga group compared to D+Gb group slighter effects of garlic juice on histopathological and biochemical changes were seen. These results indicate that garlic juice may help in the prevention of the complications of diabetes. PMID:24250639

  18. Effect of the hydroalcoholic extract and juice of Prunus divaricata fruit on blood glucose and serum lipids of normal and streptozotocin-induced diabetic rats

    PubMed Central

    Minaiyan, M.; Ghannadi, A.; Movahedian, A.; Ramezanlou, P.; Osooli, F.S.

    2014-01-01

    Prunus divaricata (Alloocheh) is a small tree cultivating in Iran, Middle East and central Asia. Prunus genus has many species with anti-oxidant, anti-hyperlipidemia and anti-hyperglycemia effects. In the present study the anti-diabetic and anti-hyperlipidemic effects of P. divaricata fruits were examined in normal and streptozotocin (STZ)-induced diabetic rats. Both groups, control and reference rats received normal saline and glibenclamide respectively. Test groups were treated with Prunus freeze dried juice (PFDJ, 200, 400, 800 mg/kg) and Prunus freeze dried extract (PFDE, 100, 200, 400 mg/kg) started at the 3rd day of the experiment and continued for 27 days thereafter. Weight changes of animals were checked periodically. Fasting blood glucose (FBG) level as well as serum triglyceride (TG), total cholesterol (TC), high density lipoprotein (HDL) and low density lipoprotein (LDL) cholesterol were determined. Different treatments had no significant effect on body weight increments of normal rats, while in diabetic rats, PFDJ (800 mg/kg) and PFDE (400 mg/kg) opposed with weight loss. In acute phase of experiment (0-8 h of 3rd day), none of tested fractions were effective in reducing FBG and serum lipids of normal rats. During the sub-acute phase (13th and 30th days) however, the greatest test doses of PFDJ (800 mg/kg) and PFDE (400 mg/kg) induced hypoglycema. In diabetic groups, PFDJ and PFDE, at all test doses, could diminish FBG during sub-acute phase of the experiment. In addition, PFDJ and PFDE at most examined doses could diminish TG significantly and they were also effective on cholesterol derivatives in different magnitude. PMID:26339257

  19. Antihyperglycemic Potential of Grewia asiatica Fruit Extract against Streptozotocin-Induced Hyperglycemia in Rats: Anti-Inflammatory and Antioxidant Mechanisms

    PubMed Central

    Khattab, Hala A. H.; El-Shitany, Nagla A.; Abdallah, Inas Z. A.; Yousef, Fatimah M.; Alkreathy, Huda M.

    2015-01-01

    Diabetes mellitus is regarded as a serious chronic disease that carries a high risk for considerable complications. In folk medicine, the edible Grewia asiatica fruit is used in a number of pathological conditions. This study aimed to investigate the possible curative effect of G. asiatica fruit ethanolic extract against streptozotocin- (STZ-) induced hyperglycemia in rats. Furthermore, mechanism of antihyperglycemic action is investigated. Hyperglycemic rats are either treated with 100 or 200?mg/kg/day G. asiatica fruits extract. Serum glucose, liver glycogen, malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD), interleukin- (IL-) 1?, and tumor necrosis factor- (TNF-) ? are measured. G. asiatica fruits extract reduces blood glucose and pancreatic MDA levels. It increases liver glycogen and pancreatic GSH contents and SOD enzyme activity. Furthermore, Grewia asiatica fruits extract decreases serum IL-1? and TNF-?. The treatment also protects against STZ-induced pathological changes in the pancreas. The results of this study indicated that G. asiatica fruit extract exerts antihyperglycemic activity against STZ-induced hyperglycemia. The improvement in the pancreatic ?-cells and antioxidant and anti-inflammatory effects of G. asiatica fruit extract may explain the antihyperglycemic effect. PMID:26347423

  20. Retinal Not Systemic Oxidative and Inflammatory Stress Correlated with VEGF Expression in Rodent Models of Insulin Resistance and Diabetes

    PubMed Central

    Mima, Akira; Qi, Weier; Hiraoka-Yamomoto, Junko; Park, Kyoungmin; Matsumoto, Motonobu; Kitada, Munehiro; Li, Qian; Mizutani, Koji; Yu, Edward; Shimada, Takeshi; Lee, Jongsoon; Shoelson, Steven E.; Jobin, Christian; Rask-Madsen, Christian; King, George L.

    2012-01-01

    Purpose. To correlate changes between VEGF expression with systemic and retinal oxidative stress and inflammation in rodent models of obesity induced insulin resistance and diabetes. Methods. Retinal VEGF mRNA and protein levels were assessed by RT-PCR and VEGF ELISA, respectively. Urinary 8-hydroxydeoxyguanosine (8-OHdG), blood levels of C-reactive protein (CRP), malondialdehyde (MDA), and CD11b/c positive cell ratio were used as systemic inflammatory markers. Retinal expression of Nox2, Nox4, and p47phox mRNA levels were measured as oxidative stress markers. TNF-?, inter-cellular adhesion molecule-1 (ICAM-1), IL1?, and activation of nuclear factor ?B (NF-?B) were used as retinal inflammatory markers. Results. Retinal VEGF mRNA and protein expression increased in Zucker diabetic fatty (ZDFfa/fa) rats and streptozotosin (STZ) induced diabetic Sprague-Dawley rats, after two months of disease, but not in Zucker fatty (ZF) rats. Systemic markers of oxidative stress and inflammation were elevated in insulin resistant and diabetic rats. Some oxidative stress and inflammatory markers (TNF-?, IL-6, ICAM-1, and IL1-?) were upregulated in the retina of ZDFfa/fa and STZ diabetic rats after 4 months of disease. In contrast, activation of NF-?B in the retina was observed in high fat fed nondiabetic and diabetic cis-NF-?BEGFP mice, ZF, ZDFfa/fa, and STZ-induced diabetic rats. Conclusions. Only persistent hyperglycemia and diabetes increased retinal VEGF expression. Some markers of inflammation and oxidative stress were elevated in the retina and systemic circulation of obese and insulin resistant rodents with and without diabetes. Induction of VEGF and its associated retinal pathologies by diabetes requires chronic hyperglycemia and factors in addition to inflammation and oxidative stress. PMID:23197686

  1. The Dipeptidyl Peptidase-4 Inhibitor Linagliptin Preserves Endothelial Function in Mesenteric Arteries from Type 1 Diabetic Rats without Decreasing Plasma Glucose

    PubMed Central

    Salheen, Salheen M.; Panchapakesan, Usha; Pollock, Carol A.; Woodman, Owen L.

    2015-01-01

    The aim of the study was to investigate the effect of the DPP-4 inhibitor linagliptin on the mechanism(s) of endothelium-dependent relaxation in mesenteric arteries from STZ-induced diabetic rats. Both normal and diabetic animals received linagliptin (2 mg/kg) daily by oral gavage for a period of 4 weeks. To measure superoxide generation in mesenteric arteries, lucigenin-enhanced chemiluminescence was used. ACh-induced relaxation of mesenteric arteries was assessed using organ bath techniques and Western blotting was used to investigate protein expression. Pharmacological tools (1μM TRAM-34, 1μM apamin, 100 nM Ibtx, 100 μM L-NNA, 10 μM ODQ) were used to distinguish between NO and EDH-mediated relaxation. Linagliptin did not affect plasma glucose, but did decrease vascular superoxide levels. Diabetes reduced responses to ACh but did not affect endothelium-independent responses to SNP. Linagliptin improved endothelial function indicated by a significant increase in responses to ACh. Diabetes impaired the contribution of both nitric oxide (NO) and endothelium-dependent hyperpolarization (EDH) to endothelium-dependent relaxation and linagliptin treatment significantly enhanced the contribution of both relaxing factors. Western blotting demonstrated that diabetes also increased expression of Nox2 and decreased expression and dimerization of endothelial NO synthase, effects that were reversed by linagliptin. These findings demonstrate treatment of type 1 diabetic rats with linagliptin significantly reduced vascular superoxide levels and preserved both NO and EDH-mediated relaxation indicating that linagliptin can improve endothelial function in diabetes independently of any glucose lowering activity. PMID:26618855

  2. Antidiabetic effect of Korean traditional Baechu (Chinese cabbage) kimchi in a type 2 diabetes model of rats.

    PubMed

    Islam, Md Shahidul; Choi, Haymie

    2009-04-01

    The present study was conducted to examine the antidiabetic effects of two dietary dosages (0.5% and 2.0%) of freeze-dried Korean traditional Baechu (Chinese cabbage) kimchi in a high-fat (HF) diet-fed, streptozotocin (STZ)-induced type 2 diabetes (T2D) rat model. Five-week-old male Sprague-Dawley rats were fed HF diet for 2 weeks and then randomly divided into four groups of eight animals: normal control (NC), diabetic control (DBC), kimchi low (KML) (0.5%), and kimchi high (KMH) (2.0%) groups. Diabetes was induced by an intraperitoneal injection of STZ (40 mg/kg of body weight) in all groups except the NC group. After 4 weeks of feeding of experimental diets, serum insulin concentrations and Homeostatic Model Assessment pancreatic beta-cell function were increased and blood glycated hemoglobin was decreased in the kimchi-fed groups compared to the DBC group, while a significant (P < .05) difference was observed only in the KMH group for serum insulin concentration. Lower fasting blood glucose and better glucose tolerance were observed in the KMH group compared to the DBC and KML groups; however, differences were not significant. Food intake, body weight gain, Homeostatic Model Assessment insulin resistance index, and serum lipid profiles were not significantly influenced by kimchi-containing diets. Data of this study suggest that dietary Baechu kimchi has some antidiabetic effects even when fed with a HF-containing diet. Better results are possible if it is consumed with normal or low-fat rather than HF-containing diet. PMID:19459728

  3. Effects of 4-phenylbutyric acid on the process and development of diabetic nephropathy induced in rats by streptozotocin: Regulation of endoplasmic reticulum stress-oxidative activation

    SciTech Connect

    Luo Zhifeng; Feng Bing; Mu Jiao; Qi Wei; Zeng Wei; Guo Yanhong; Pang Qi; Ye Zilin; Liu Li; Yuan Fahuan

    2010-07-15

    Oxidative stress may contribute to the pathogenesis of diabetic nephropathy (DN), although the precise regulatory mechanism is still unclear. Recent reports have shown that chemical molecular chaperone 4-phenylbutyric acid (4-PBA) can suppress oxidative stress by attenuating endoplasmic reticulum (ER) stress. We therefore hypothesized that 4-PBA could provide renoprotection through the suppression of oxidative stress in DN rats. Male Sprague-Dawley (SD) rats were randomly divided into three groups: a normal control (NC) group, a streptozotocin (STZ)-induced DN model group, and a DN plus 4-PBA (1 g/kg) treatment group. At the end of 4, 8, and 12 weeks, hydroxyproline content, NADPH oxidase activity and the expression of phosphorylation of inositol-requiring enzyme-1{alpha} (p-IRE1{alpha}), p47phox, nitrotyrosine (NT) and NF-E2-related factor 2 (Nrf2) in the kidneys of all rats were determined; malondialdehyde (MDA) levels and superoxide dismutase (SOD) activity in serum and urine were also detected; renal nuclear factor {kappa}B (NF-{kappa}B) activity in all of the rats was examined at the end of 12 weeks. Compared with the NC group, the DN rats showed a significant increase in hydroxyproline content, NADPH oxidase activity, NF-{kappa}B activity, the expression of p-IRE1{alpha}, p47phox, NT and Nrf2 in renal tissue; markedly, MDA levels were higher and SOD activity was lower in serum and urine of DN rats than in NC rats for the indicated time. These alterations were inhibited by the administration of 4-PBA. These findings first demonstrated that treatment with 4-PBA significantly inhibits the process and development of diabetic nephropathy in rats through the regulation of ER stress-oxidative activation.

  4. Dysregulated miR-103 and miR-143 expression in peripheral blood mononuclear cells from induced prediabetes and type 2 diabetes rats.

    PubMed

    Vatandoost, Nasimeh; Amini, Masoud; Iraj, Bijan; Momenzadeh, Sedigheh; Salehi, Rasoul

    2015-11-01

    The progression from normal glucose tolerance (NGT) to type 2 diabetes (T2D) occurs through an intermediate state of glucose intolerance known as pre-diabetes. This transition is usually a gradual phenomenon that occurs over 5-10 years. Among the routinely practiced T2D screening criteria, like, FPG, IFG, IGT or HbA1c, still the issue of a preferable one is debated. The newly emerged microRNAs are created much hope to act as a class of suitable diabetes gene signature detectable at an early stage of the disease development. Although T2D related miRNA fluctuations are reported from the main insulin target organs, sampling of these organs for the sake of screening due to its invasive nature is not practicable. Peripheral blood mononuclear cells (PBMCs) are in constant touch with all body organs hence may exhibit the trace of miRNA changes which take place in insulin target organs. In this study we have evaluated miR-103 and miR-143 expression in three groups of rats namely; normal control, high fat diet (HFD) which is corresponding to prediabetes state, and high fat diet/streptozotocin (STZ) induced T2D. Quantitative real time PCR was used for profiling the selected miRNA expression at various time intervals of the three defined groups of rats. In prediabetes and overt diabetes stages, miR-103 showed significantly elevated expression in PBMC specimens compared to the normal healthy control group. Overexpression pattern of mir-143 was statistically significant in T2D compared to non-diabetic controls. However in HFD (prediabetic) rats also we observed an increasing pattern of miR-143 compared to the normal controls but it was not statistically significant. PMID:26164754

  5. Profiling of cardiac ?-adrenoceptor subtypes in the cardiac left ventricle of rats with metabolic syndrome: Comparison with streptozotocin-induced diabetic rats.

    PubMed

    Okatan, Esma N; Tuncay, Erkan; Hafez, Gaye; Turan, Belma

    2015-07-01

    Little is known about metabolic syndrome (MetS)-associated cardiomyopathy, especially in relation to the role and contribution of beta-adrenoceptor (?-AR) subtypes. Therefore, we examined the roles of ?-AR subtypes in the cardiac function of rats with MetS (MetS group) and compared it with that of rats with streptozotocin (STZ)-induced diabetes (STZ group). Compared with the normal control rats, the protein levels of cardiac ?1- and ?2-AR in the MetS group were significantly decreased and with no changes in their mRNA levels, whereas the protein levels of ?3-AR were similar to those of the controls. However, as shown previously, the protein levels of cardiac ?1- and ?2-AR in the STZ group were decreased, whereas the ?3-AR levels were significantly increased by comparison with the controls. Additionally, the mRNA levels of ?2- and ?3-AR were increased, but ?1-AR mRNA was decreased in the STZ group. Furthermore, left ventricular developed pressure responses to ?3-AR agonist BRL37344 were increased in the STZ group but not in the MetS group, whereas for both groups, the responses to noradrenaline were not different from those of the controls. However, the response to stimulation with high concentrations of fenoterol was depressed in the MetS group, compared with the controls, but not in the STZ group. Consequently, our data suggest that the contribution of the ?-AR system to cardiac dysfunction in the rats with MetS is not the same as that in the STZ group, although they have similar cardiac dysfunction with similar ultrastructural changes to the myocardium. PMID:25994289

  6. Isolation and structural characterization of 2R, 3R taxifolin 3-O-rhamnoside from ethyl acetate extract of Hydnocarpus alpina and its hypoglycemic effect by attenuating hepatic key enzymes of glucose metabolism in streptozotocin-induced diabetic rats.

    PubMed

    Balamurugan, Rangachari; Vendan, Subramanian Ezhil; Aravinthan, Adithan; Kim, Jong-Hoon

    2015-04-01

    Hydnocarpus alpina Wt. (Flacourtiaceae) (H. alpina) is a large tree traditionally used to treat leprosy; it also posses antidiabetic property. The present study was undertaken to isolate, characterize and to evaluate the antidiabetic effect of 2R, 3R taxifolin 3-O-rhamnoside. (rhamnoside) and its impact on carbohydrate metabolic key enzymes in control and streptozotocin (STZ)-induced diabetic rats. Diabetes mellitus was induced by a single intraperitoneal injection of streptozotocin (STZ) (40 mg/kg). Oral administration of rhamnoside for 21 days significantly reduced food intake, calorie intake, blood glucose and glycosylated hemoglobin levels, and improved plasma insulin levels. Administration of rhamnoside showed significant increase in the body weight, body composition (Lean body weight (LBW) and retro body fat), glycolytic hexokinase, glucose-6-phophate dehydrogenase and pyruvate kinase levels where as significant decrease was observed in the levels of glucose-6-phosphatase fructose-1, 6-bisphosphatase and lactate dehydrogenase in diabetic treated rats. Further, administration of rhamnoside significantly improved the glycogen content, glycogen synthase and glycogen phosphorylase, suggesting the antihyperglycemic potential of rhamnoside in diabetic rats. The results obtained were compared with glibenclamide a standard hypoglycaemic drug. Immunohistopathological study of pancreas revealed increased number of β-cells and insulin granules in diabetes-induced rats after treatment with rhamnoside for 21 days. Furthermore, Co-administration of rhamnoside (50 mg/kg) with nifedipine (13.6 mg/kg), a Ca(2+)ion channel blocker, or nicorandil (6.8 mg/kg), an ATP-sensitive K(+) ion channel opener, reveals the insulin secretion property of rhamnoside via a K(+)-ATP channels dependent pathway in diabetic rats. In conclusion, rhamnoside normalized blood glucose, glycosylated hemoglobin, key hepatic enzymes and glycogen content by increasing insulin secretion via K(+)-ATP channels dependent signaling pathway. The results suggest that the rhamnoside from H. alpina could be used as a therapeutic agent to treat diabetes mellitus. PMID:25698613

  7. The Attenuation of Moutan Cortex on Oxidative Stress for Renal Injury in AGEs-Induced Mesangial Cell Dysfunction and Streptozotocin-Induced Diabetic Nephropathy Rats

    PubMed Central

    Zhang, Minghua; Feng, Liang; Gu, Junfei; Ma, Liang; Qin, Dong; Wu, Chan; Jia, Xiaobin

    2014-01-01

    Oxidative stress (OS) has been regarded as one of the major pathogeneses of diabetic nephropathy (DN) through damaging kidney which is associated with renal cells dysfunction. The aim of this study was to investigate whether Moutan Cortex (MC) could protect kidney function against oxidative stress in vitro or in vivo. The compounds in MC extract were analyzed by HPLC-ESI-MS. High-glucose-fat diet and STZ (30?mg?kg?1) were used to induce DN rats model, while 200??g?mL?1 AGEs were for HBZY-1 mesangial cell damage. The treatment with MC could significantly increase the activity of SOD, glutathione peroxidase (GSH-PX), and catalase (CAT). However, lipid peroxidation malondialdehyde (MDA) was reduced markedly in vitro or in vivo. Furthermore, MC decreased markedly the levels of blood glucose, serum creatinine, and urine protein in DN rats. Immunohistochemical assay showed that MC downregulated significantly transforming growth factor beta 2 (TGF-?2) protein expression in renal tissue. Our data provided evidence to support this fact that MC attenuated OS in AGEs-induced mesangial cell dysfunction and also in high-glucose-fat diet and STZ-induced DN rats. PMID:24876912

  8. Effect of nicotinamide on amino acids content in bone collagen depending on biological availability of vitamins in diabetic rats.

    PubMed

    Guzyk, M M; Sergiichuk, Iu T; Dyakun, K O; Yanitska, L V; Kuchmerovska, T M

    2014-01-01

    Connective tissue is highly susceptible to imbalances induced by diabetes. Diabetes-related osteopenia, decreased bone strength etc. may be associated with altered metabolism of various collagens: Although it is assumed that alterations in collagen amino acids (AA) may strongly affect protein properties andphysiological functions, however, very limited evidences are present at the moment regarding AA composition of bone type I collagen and its relevance to abnormal availability of vitamins which are necessary for collagen synthesis in diabetes. We have tested whether nicotinamide (NAm) can influence type Icollagen formation and AA composition as well as vitamins availability in diabetes. After 4 weeks of STZ-induced diabetes (60 mg/ kg) male Wistar rats were injected for 2 weeks with/without NAm (200 mg/kg b. w). Acid extraction of type I collagen from the bones was performed with following stepwise salting out. The content of type I collagen after its acid extraction from the bones was estimated by the amounts of hydroxyproline. Amino acids were assayed by cation exchange chromatography Diabetes-associated changes in AA composition of type I collagen mainly affect those amino acids which are known to be involved in helix formation and cross-linking of the molecules. Diabetes was found to significantly reduce bone collagen contents of o-Pro, Gly, Ala, o-Lys and Pro, whereas Lys, His, Arg, Glu, Thr, Leu, Phe contents were elevated (P < 0.05). NAm treatment was able to partially normalise AA contents. In diabetes, blood serum and hepatic vitamin C and B3 contents were shown to be significantly lowered, whereas a-tocopherol was slightly increased compared with control (P < 0.05). Restoration of circulatory and liver vitamin C and B3 was observed. The data demonstrate the close relationship between the diabetes-associated decrease in type I collagen deposition, altered amino acids metabolism and impaired availability of vitamins, which are necessary for collagen synthesis. Thus, NAm might be a useful agent for treatment of bone failures related to diabetes. PMID:25509193

  9. Ethanolic extract of Commiphora mukul gum resin attenuates streptozotocin-induced alterations in carbohydrate and lipid metabolism in rats

    PubMed Central

    Ramesh, B.; Karuna, R.; Sreenivasa Reddy, S.; Sudhakara, G.; Saralakumari, D.

    2013-01-01

    The purpose of this study was to investigate the effects of Commiphora mukul gum resin ethanolic extract (CMEEt) administration against altered activities of key enzymes of carbohydrate metabolism, lipid metabolism and changes in glycogen content (liver and muscle) and lipids (liver and heart) in streptozotocin (STZ) induced insulin deficient diabetic Wistar albino rats. Diabetes was induced by intraperitoneal injection of STZ (55 mg/kg body wt) to male Wistar rats. The animals were divided into four groups: Control (C), control-treated (C+CM), diabetic (D) and diabetic-treated group (D+CM). Diabetic-treated and control-treated rats were treated with C. mukul gum resin ethanolic extract (CMEEt) in 2 ml distilled water, orally (200 mg/kg body weight/day for 60 days). At the end of the experimental period, biochemical parameters related to carbohydrate and lipid metabolism were assayed. The significant enhancement in tissue lipids (heart and liver) total cholesterol, triglycerides, phospholipids and free fatty acids of diabetic rats were nearer to normalized in diabetic treated rats (D+CM). Alterations in the activities of enzymes of glucose metabolism (hexokinase, phosphofructokinase, pyruvate kinase, and glucose-6-phosphatase, fructose-1,6-bisphosphatase and glucose-6-phosphate dehydrogenase) and lipid metabolism (fatty acid synthase, malic enzyme and lipoprotein lipase) as observed in diabetic (D) rats were prevented with CMEEt administration. In conclusion, our findings indicate improvement of glucose and lipid metabolisms in STZ induced diabetic rats by treatment with Commiphora mukul and suggest that the plant can be used as an adjuvant for the prevention and/or management of insulin deficiency and disorder related to it.

  10. Total parenteral nutrition in diabetic rats

    SciTech Connect

    Norcross, E.D.; Stein, T.P.

    1986-03-01

    Parenteral Nutrition with hypertonic glucose is frequently given to diabetic patients. Large amounts of insulin can be required. The purpose of this investigation was to develop a totally parenterally nourished diabetic rat model. 200 g Female Sprague Dawley rats were made diabetic by i.v. injection of streptozotocin (50 mg/kg). Rats were then allowed to recover for at least 1 week before undergoing surgical insertion of a central venous catheter for parenteral feeding. TPN was begun 3 days after surgery. Prior to this they were allowed unlimited access to food and water. Control (non-streptozotocin treated) rats were run at the same time. Protein turnover was investigated by using /sup 15/N glycine. Preliminary results: diabetic rats given mostly fat as a calorie source survived well in the absence of exogenous insulin whereas those that were given glucose only as their non-protein calorie source showed poor survival even with exogenous insulin. N balance and protein turnover in the lipid treated diabetic rats were comparable to the non-diabetic control rats.

  11. Soybeans Ameliolate Diabetic Nephropathy in Rats

    PubMed Central

    Choi, Young Eun; Ahn, Soo Kyung; Lee, Won Taek; Lee, Jong Eun; Park, Seung Hwa; Yoon, Bang Bu

    2010-01-01

    Diabetic nephropathy is one of the most frequent and serious complications of diabetes mellitus. Soybeans have been shown to reduce urinary albumin excretion and total cholesterol in non-diabetic patients with nephrotic syndrome. However, reports focusing specifically on diabetic nephropathy are scarce and the available results are inconsistent. It was reported that soybean consumption reduced urinary protein excretion in type 1 diabetic patients with diabetic nephropathy, whereas it was found to elicit an increase in urinary protein excretion when soybeans were consumed by type 2 diabetic patients. This study aims to investigate the effects of soybean in diabetic nephropathy, particularly the effects of consuming soybeans on the histopathology of diabetic nephropathy, using aquaporin (AQP) and osteopontin (OPN) expression as diagnostic markers. Male Sprague-Dawley rats were assigned to one of three groups: control, diabetic with red chow diet and diabetic with soybean diet. For histological examination, the expression of OPN and AQP, renal function and hemoglobin A1c were evaluated at the end of the study. Improvements in glomerular and tubulointerstitial lesions were demonstrated in the diabetic rat group given a soybean diet. OPN and AQP expression were suppressed in the kidney specimens of diabetic rats with the soybean diet. In conclusion, soybeans may prevent the weight loss and morphological disruption of the kidney associated with diabetes mellitus. Soybeans also may improve glycemic control. It seems likely that long-term control of blood glucose levels using a soybean diet could prevent the progression of diabetes mellitus, and therefore, nephropathy could be prevented. PMID:18955330

  12. Chinese cabbage (Brassica campestris L.) does not improve glucose tolerance, serum insulin, or blood lipid profiles in a rat model of type-2 diabetes.

    PubMed

    Islam, M S; Choi, H

    2008-11-01

    The present study was conducted to investigate the effects of a low (0.5%) and a high (2.0%) dietary dose of freeze-dried Chinese cabbage (CC) (Brassica campestris L.) powder in a type-2 diabetes (T2D) model of rats. Five-week-old male Sprague-Dawley rats were fed a high fat (HF)-containing diet for 2 wk then randomly divided into 4 groups of 8 animals, namely: normal control (NC), diabetic control (DBC), Chinese cabbage low (CCL, 0.5%), and Chinese cabbage high (CCH, 2.0%) groups. Diabetes was induced by an intraperitoneal injection of streptozotocin (STZ; 40 mg/kg body weight) in all groups except the NC group. After 4 wk feeding of experimental diets, although food intake was not different among the DBC, CCL, and CCH groups, body weight gain was significantly (P < 0.05) higher in the CCH group compared to the DBC group. Relatively higher serum insulin concentrations and better glucose tolerance were observed in the CC-fed groups compared to the DBC group; however, the results were not significantly different. Fasting blood glucose, blood glycated hemoglobin (HbA1c), liver weight, and liver glycogen levels were not influenced by the CC-containing diets. Additionally, hypertriglyceridemic tendencies were observed in the CC-fed groups compared to the NC and DBC groups, while difference observed for total-, HDL-, and LDL-cholesterols between the groups were negligible. Results of this study suggest that up to 2% dietary dose of freeze-dried CC is not significantly effective to reduce diabetes-related symptoms in an HF diet-fed STZ-induced T2D model of rats. PMID:19021803

  13. Chlorophytum borivilianum Root Extract Maintains near Normal Blood Glucose, Insulin and Lipid Profile Levels and Prevents Oxidative Stress in the Pancreas of Streptozotocin-Induced Adult Male Diabetic Rats

    PubMed Central

    Giribabu, Nelli; Kumar, Kilari Eswar; Rekha, Somesula Swapna; Muniandy, Sekaran; Salleh, Naguib

    2014-01-01

    The effect of C. borivilianum root on blood glucose, glycated hemoglobin (HbAIc), insulin and lipid profile levels in diabetes mellitus are not fully understood. This study therefore investigated the effect of C. borivilianum root on the above parameters and oxidative stress of the pancreas in diabetes. Methods: C. borivilianum root aqueous extract (250 and 500 mg/kg/day) was administered to streptozotocin (STZ)-induced male diabetic rats for 28 days. Body weight, blood glucose, HbA1c, insulin, lipid profile levels and glucose homeostasis indices were determined. Histopathological changes and oxidative stress parameters i.e. lipid peroxidation (LPO) and antioxidant enzymes activity levels of the pancreas were investigated. Results: C. borivilianum root extract treatment to diabetic rats maintained near normal body weight, blood glucose, HbA1c, lipid profile and insulin levels with higher HOMA-β cell functioning index, number of Islets/pancreas, number of β-cells/Islets however with lower HOMA-insulin resistance (IR) index as compared to non-treated diabetic rats. Negative correlations between serum insulin and blood glucose, HbA1c, triglyceride (TG) and total cholesterol (TC) levels were observed. C. borivilianum root extract administration prevented the increase in lipid peroxidation and the decrease in activity levels of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) with mild histopathological changes in the pancreas of diabetic rats. Conclusions: C. borivilianum root maintains near normal levels of these metabolites and prevented oxidative stress-induced damage to the pancreas in diabetes. PMID:25249786

  14. Energy balance of pregnant diabetic rats.

    PubMed

    Yamada, Ruth; Griggio, Mauro A; Luz, Jacqueline

    2002-05-01

    Pregnancy and diabetes lead to metabolic alterations in the energy balance that may not be completely independent. The objective of the present study was to look at the alterations induced by type 1 diabetes mellitus on the energy balance of pregnant rats and the offspring. Diabetes was induced by streptozotocin injection 15 d before the starting of pregnancy. The rats had their energy balance variables followed for 21 d. Protein, fat and energy content of dams was determined from samples of the carcasses. Pregnancy led to increased energy intake, energy gain and energy expenditure as well as higher gross food efficiency than non-pregnant counterparts. Diabetes increased metabolizable energy intake but not the energy gain of the animals: they had very high energy expenditure, so that diabetes blocked the improvement in gross food efficiency shown during pregnancy. Offspring from diabetic dams were born with lower body weight. Pregnant animals did not present the usual energy storage as seen by lower energy gain of diabetic dams as well as by the lower fat content in the carcasses of pregnant diabetic rats. It is concluded that diabetes impairs the energy variables usually enhanced by pregnancy alone. PMID:12010589

  15. The Soybean Peptide Vglycin Preserves the Diabetic β-cells through Improvement of Proliferation and Inhibition of Apoptosis

    PubMed Central

    Jiang, Hua; Tong, Yuxing; Yan, Dongjing; Jia, Shaohui; Ostenson, Claes-Goran; Chen, Zhengwang

    2015-01-01

    Replenishment of insulin-producing pancreatic β-cells would be beneficial in diabetes. The number of β-cells is maintained primarily by self-neogenesis to compensate for β-cell failure, loss or dedifferentiation. We present here a polypeptide vglycin, which was isolated and purified from germinating pea seeds. Vglycin exhibited positive effects in our diabetic models by promoting the proliferation and suppressing the apoptosis and dedifferentiation of β-cells. Vglycin promoted the restoration of β-cells in both young streptozotocin (STZ)-induced type 1 diabetic SD rats and in aged high-fat diet with (or without) STZ-induced type 2 diabetic C57BL/6 mice. We demonstrated that vglycin triggers this positive signaling by activating the insulin receptor and corresponding transcription factors. Impaired insulin sensitivity and glucose tolerance in aged T2DM mice were dramatically improved after long-term vglycin treatment, consistent with the altered level of inflammatory factor IL-1β/6. In addition, energy expenditure and body weights were significantly decreased in the mouse models after vglycin therapy. These results provide insight into the protective effects of vglycin on ameliorating β-cell function in standing glucolipotoxicity. Thus, vglycin may represent a new therapeutic agent for preventing and treating diabetes by replenishing endogenous insulin-positive cells. PMID:26510947

  16. Spatio-temporal expression and functional involvement of transient receptor potential vanilloid 1 in diabetic mechanical allodynia in rats.

    PubMed

    Cui, Yuan-Yuan; Xu, Hao; Wu, Huang-Hui; Qi, Jian; Shi, Juan; Li, Yun-Qing

    2014-01-01

    Diabetic neuropathic pain (DNP) is one of the most common clinical manifestations of diabetes mellitus (DM), which is characterized by prominent mechanical allodynia (DMA). However, the molecular mechanism underlying it has not fully been elucidated. In this study, we examined the spatio-temporal expression of a major nociceptive channel protein transient receptor potential vanilloid 1 (TRPV1) and analyzed its functional involvement by intrathecal (i.t.) application of TRPV1 antagonists in streptozocin (STZ)-induced DMA rat models. Western blot and immunofluorescent staining results showed that TRPV1 protein level was significantly increased in the soma of the dorsal root ganglion (DRG) neurons on 14 days after STZ treatment (DMA 14 d), whereas those in spinal cord and skin (mainly from the central and peripheral processes of DRG neurons) had already been enhanced on DMA 7 d to peak on DMA 14 d. qRT-PCR experiments confirmed that TRPV1 mRNA level was significantly up-regulated in the DRG on DMA 7 d, indicating a preceding translation of TRPV1 protein in the soma but preferential distribution of this protein to the processes under the DMA conditions. Cell counting assay based on double immunostaining suggested that increased TRPV1-immunoreactive neurons were likely to be small-sized and CGRP-ergic. Finally, single or multiple intrathecal applications of non-specific or specific TRPV1 antagonists, ruthenium red and capsazepine, at varying doses, effectively alleviated DMA, although the effect of the former was more prominent and long-lasting. These results collectively indicate that TRPV1 expression dynamically changes during the development of DMA and this protein may play important roles in mechanical nociception in DRG neurons, presumably through facilitating the release of CGRP. PMID:25020137

  17. Spatio-Temporal Expression and Functional Involvement of Transient Receptor Potential Vanilloid 1 in Diabetic Mechanical Allodynia in Rats

    PubMed Central

    Wu, Huang-Hui; Qi, Jian; Shi, Juan; Li, Yun-Qing

    2014-01-01

    Diabetic neuropathic pain (DNP) is one of the most common clinical manifestations of diabetes mellitus (DM), which is characterized by prominent mechanical allodynia (DMA). However, the molecular mechanism underlying it has not fully been elucidated. In this study, we examined the spatio-temporal expression of a major nociceptive channel protein transient receptor potential vanilloid 1 (TRPV1) and analyzed its functional involvement by intrathecal (i.t.) application of TRPV1 antagonists in streptozocin (STZ)-induced DMA rat models. Western blot and immunofluorescent staining results showed that TRPV1 protein level was significantly increased in the soma of the dorsal root ganglion (DRG) neurons on 14 days after STZ treatment (DMA 14 d), whereas those in spinal cord and skin (mainly from the central and peripheral processes of DRG neurons) had already been enhanced on DMA 7 d to peak on DMA 14 d. qRT-PCR experiments confirmed that TRPV1 mRNA level was significantly up-regulated in the DRG on DMA 7 d, indicating a preceding translation of TRPV1 protein in the soma but preferential distribution of this protein to the processes under the DMA conditions. Cell counting assay based on double immunostaining suggested that increased TRPV1-immunoreactive neurons were likely to be small-sized and CGRP-ergic. Finally, single or multiple intrathecal applications of non-specific or specific TRPV1 antagonists, ruthenium red and capsazepine, at varying doses, effectively alleviated DMA, although the effect of the former was more prominent and long-lasting. These results collectively indicate that TRPV1 expression dynamically changes during the development of DMA and this protein may play important roles in mechanical nociception in DRG neurons, presumably through facilitating the release of CGRP. PMID:25020137

  18. Diabetes enhances oxidative stress-induced TRPM2 channel activity and its control by N-acetylcysteine in rat dorsal root ganglion and brain.

    PubMed

    Sözbir, Ercan; Nazıroğlu, Mustafa

    2016-04-01

    N-acetylcysteine (NAC) is a sulfhydryl donor antioxidant that contributes to the regeneration of glutathione (GSH) and also scavengers via a direct reaction with free oxygen radicals. Recently, we observed a modulatory role of NAC on GSH-depleted dorsal root ganglion (DRG) cells in rats. NAC may have a protective role on oxidative stress and calcium influx through regulation of the TRPM2 channel in diabetic neurons. Therefore, we investigated the effects of NAC on DRG TRPM2 channel currents and brain oxidative stress in streptozotocin (STZ)-induced diabetic rats. Thirty-six rats divided into four groups: control, STZ, NAC and STZ + NAC. Diabetes was induced in the STZ and STZ + NAC groups by intraperitoneal STZ (65 mg/kg) administration. After the induction of diabetes, rats in the NAC and STZ + NAC groups received NAC (150 mg/kg) via gastric gavage. After 2 weeks, DRG neurons and the brain cortex were freshly isolated from rats. In whole-cell patch clamp experiments, TRPM2 currents in the DRG following diabetes induction with STZ were gated by H2O2. TRPM2 channel current densities in the DRG and lipid peroxidation levels in the DRG and brain were higher in the STZ groups than in controls; however, brain GSH, GSH peroxidase (GSH-Px), vitamin C and vitamin E concentrations and DRG GSH-Px activity were decreased by diabetes. STZ + H2O2-induced TRPM2 gating was totally inhibited by NAC and partially inhibited by N-(p-amylcinnamoyl) anthranilic acid (ACA) and 2-aminoethyl diphenylborinate (2-APB). GSH-Px activity and lipid peroxidation levels were also attenuated by NAC treatment. In conclusion, we observed a modulatory role of NAC on oxidative stress and Ca(2+) entry through the TRPM2 channel in the diabetic DRG and brain. Since excessive oxidative stress and overload Ca(2+) entry are common features of neuropathic pain, our findings are relevant to the etiology and treatment of pain neuropathology in DRG neurons. PMID:26612073

  19. Advanced glycation end products (AGEs) co-localize with AGE receptors in the retinal vasculature of diabetic and of AGE-infused rats.

    PubMed Central

    Stitt, A. W.; Li, Y. M.; Gardiner, T. A.; Bucala, R.; Archer, D. B.; Vlassara, H.

    1997-01-01

    Advanced glycation end products (AGEs), formed from the nonenzymatic glycation of proteins and lipids with reducing sugars, have been implicated in many diabetic complications; however, their role in diabetic retinopathy remains largely unknown. Recent studies suggest that the cellular actions of AGEs may be mediated by AGE-specific receptors (AGE-R). We have examined the immunolocalization of AGEs and AGE-R components R1 and R2 in the retinal vasculature at 2, 4, and 8 months after STZ-induced diabetes as well as in nondiabetic rats infused with AGE bovine serum albumin for 2 weeks. Using polyclonal or monoclonal anti-AGE antibodies and polyclonal antibodies to recombinant AGE-R1 and AGE-R2, immunoreactivity (IR) was examined in the complete retinal vascular tree after isolation by trypsin digestion. After 2, 4, and 8 months of diabetes, there was a gradual increase in AGE IR in basement membrane. At 8 months, pericytes, smooth muscle cells, and endothelial cells of the retinal vessels showed dense intracellular AGE IR. AGE epitopes stained most intensely within pericytes and smooth muscle cells but less in basement membrane of AGE-infused rats compared with the diabetic group. Retinas from normal or bovine-serum-albumin-infused rats were largely negative for AGE IR. AGE-R1 and -R2 co-localized strongly with AGEs of vascular endothelial cells, pericytes, and smooth muscle cells of either normal, diabetic, or AGE-infused rat retinas, and this distribution did not vary with each condition. The data indicate that AGEs accumulate as a function of diabetes duration first within the basement membrane and then intracellularly, co-localizing with cellular AGE-Rs. Significant AGE deposits appear within the pericytes after long-term diabetes or acute challenge with AGE infusion conditions associated with pericyte damage. Co-localization of AGEs and AGE-Rs in retinal cells points to possible interactions of pathogenic significance. Images Figure 1 Figure 2 Figure 3 PMID:9033268

  20. A primary role for kinin B1 receptor in inflammation, organ damage, and lethal thrombosis in a rat model of septic shock in diabetes

    PubMed Central

    Tidjane, N; Hachem, A; Zaid, Y; Merhi, Y; Gaboury, L; Girolami, J-P; Couture, R

    2015-01-01

    Diabetes mellitus and septic shock increase the incidence of mortality by thrombosis. Although kinin B1 receptor (B1R) is involved in both pathologies, its role in platelet function and thrombosis remains unknown. This study investigates the expression, the inflammatory, and pro-thrombotic effects of B1R in a model of septic shock in diabetic rats. Sprague-Dawley rats were made diabetic with streptozotocin (STZ) (65 mg/kg, i.p.). Four days later, control and STZ-diabetic rats were injected with lipopolysaccharide (LPS) (2 mg/kg, i.p.) or the vehicle. B1R antagonist (SSR240612, 10 mg/kg by gavage) was given either acutely (12 and 24 h prior to endpoint analysis) or daily for up to 7 days. Moreover, a 7-day treatment was given either with cyclooxygenase (COX)-2 inhibitor (niflumic acid, 5 mg/kg, i.p.), non-selective COX-1 and COX-2 inhibitor (indomethacin, 10 mg/kg, i.p.), non-selective nitric oxide synthase (NOS) inhibitor (L-NAME, 50 mg/kg by gavage), iNOS inhibitor (1400W, 5 mg/kg, i.p.), or heparin (100 IU/kg, s.c.). The following endpoints were measured: edema and vascular permeability (Evans blue dye), B1R expression (qRT-PCR, western blot, flow cytometry), aggregation in platelet-rich plasma (optical aggregometry), and organ damage (histology). Rats treated with STZ, LPS, and STZ plus LPS showed significant increases in edema and vascular permeability (heart, kidney, lung, and liver) and increased expression of B1R in heart and kidney (mRNA) and platelets (protein). Lethal septic shock induced by LPS was enhanced in STZ-diabetic rats and was associated with lung and kidney damage, including platelet micro-aggregate formation. SSR240612 prevented all these abnormalities as well as STZ-induced hyperglycemia and LPS-induced hyperthermia. Similarly to SSR240612, blockade of iNOS and COX-2 improved survival. Data provide the first evidence that kinin B1R plays a primary role in lethal thrombosis in a rat model of septic shock in diabetes. Pharmacological rescue was made possible with B1R antagonism or by inhibition of iNOS and COX-2, which may act as downstream mechanisms. PMID:26413099

  1. Quercetin and allopurinol ameliorate kidney injury in STZ-treated rats with regulation of renal NLRP3 inflammasome activation and lipid accumulation.

    PubMed

    Wang, Chuang; Pan, Ying; Zhang, Qing-Yu; Wang, Fu-Meng; Kong, Ling-Dong

    2012-01-01

    Hyperuricemia, hyperlipidemia and inflammation are associated with diabetic nephropathy. The NLRP3 inflammasome-mediated inflammation is recently recognized in the development of kidney injury. Urate and lipid are considered as danger signals in the NLRP3 inflammasome activation. Although dietary flavonoid quercetin and allopurinol alleviate hyperuricemia, dyslipidmia and inflammation, their nephroprotective effects are currently unknown. In this study, we used streptozotocin (STZ)-induced diabetic nephropathy model with hyperuricemia and dyslipidemia in rats, and found over-expression of renal inflammasome components NLRP3, apoptosis-associated speck-like protein and Caspase-1, resulting in elevation of IL-1? and IL-18, with subsequently deteriorated renal injury. These findings demonstrated the possible association between renal NLRP3 inflammasome activation and lipid accumulation to superimpose causes of nephrotoxicity in STZ-treated rats. The treatment of quercetin and allopurinol regulated renal urate transport-related proteins to reduce hyperuricemia, and lipid metabolism-related genes to alleviate kidney lipid accumulation in STZ-treated rats. Furthermore, quercetin and allopurinol were found to suppress renal NLRP3 inflammasome activation, at least partly, via their anti-hyperuricemic and anti-dyslipidemic effects, resulting in the amelioration of STZ-induced the superimposed nephrotoxicity in rats. These results may provide a basis for the prevention of diabetes-associated nephrotoxicity with urate-lowering agents such as quercetin and allopurinol. PMID:22701621

  2. Dendrobium chrysotoxum Lindl. Alleviates Diabetic Retinopathy by Preventing Retinal Inflammation and Tight Junction Protein Decrease

    PubMed Central

    Yu, Zengyang; Gong, Chenyuan; Lu, Bin; Yang, Li; Sheng, Yuchen; Ji, Lili; Wang, Zhengtao

    2015-01-01

    Diabetic retinopathy (DR) is a serious complication of diabetes mellitus. This study aimed to observe the alleviation of the ethanol extract of Dendrobium chrysotoxum Lindl. (DC), a traditional Chinese herbal medicine, on DR and its engaged mechanism. After DC (30 or 300?mg/kg) was orally administrated, the breakdown of blood retinal barrier (BRB) in streptozotocin- (STZ-) induced diabetic rats was attenuated by DC. Decreased retinal mRNA expression of tight junction proteins (including occludin and claudin-1) in diabetic rats was also reversed by DC. Western blot analysis and retinal immunofluorescence staining results further confirmed that DC reversed the decreased expression of occludin and claudin-1 proteins in diabetic rats. DC reduced the increased retinal mRNA expressions of intercellular adhesion molecule-1 (ICAM-1), tumor necrosis factor ? (TNF?), interleukin- (IL-) 6, and IL-1? in diabetic rats. In addition, DC alleviated the increased 1 and phosphorylated p65, I?B, and I?B kinase (IKK) in diabetic rats. DC also reduced the increased serum levels of TNF?, interferon-? (IFN-?), IL-6, IL-1?, IL-8, IL-12, IL-2, IL-3, and IL-10 in diabetic rats. Therefore, DC can alleviate DR by inhibiting retinal inflammation and preventing the decrease of tight junction proteins, such as occludin and claudin-1. PMID:25685822

  3. Vascular endothelial growth factor-A165b prevents diabetic neuropathic pain and sensory neuronal degeneration.

    PubMed

    Hulse, Richard P; Beazley-Long, Nicholas; Ved, Nikita; Bestall, Samuel M; Riaz, Hamza; Singhal, Priya; Ballmer Hofer, Kurt; Harper, Steve J; Bates, David O; Donaldson, Lucy F

    2015-10-01

    Diabetic peripheral neuropathy affects up to half of diabetic patients. This neuronal damage leads to sensory disturbances, including allodynia and hyperalgesia. Many growth factors have been suggested as useful treatments for prevention of neurodegeneration, including the vascular endothelial growth factor (VEGF) family. VEGF-A is generated as two alternative splice variant families. The most widely studied isoform, VEGF-A165a is both pro-angiogenic and neuroprotective, but pro-nociceptive and increases vascular permeability in animal models. Streptozotocin (STZ)-induced diabetic rats develop both hyperglycaemia and many of the resulting diabetic complications seen in patients, including peripheral neuropathy. In the present study, we show that the anti-angiogenic VEGF-A splice variant, VEGF-A165b, is also a potential therapeutic for diabetic neuropathy. Seven weeks of VEGF-A165b treatment in diabetic rats reversed enhanced pain behaviour in multiple behavioural paradigms and was neuroprotective, reducing hyperglycaemia-induced activated caspase 3 (AC3) levels in sensory neuronal subsets, epidermal sensory nerve fibre loss and aberrant sciatic nerve morphology. Furthermore, VEGF-A165b inhibited a STZ-induced increase in Evans Blue extravasation in dorsal root ganglia (DRG), saphenous nerve and plantar skin of the hind paw. Increased transient receptor potential ankyrin 1 (TRPA1) channel activity is associated with the onset of diabetic neuropathy. VEGF-A165b also prevented hyperglycaemia-enhanced TRPA1 activity in an invitro sensory neuronal cell line indicating a novel direct neuronal mechanism that could underlie the anti-nociceptive effect observed invivo. These results demonstrate that in a model of TypeI diabetes VEGF-A165b attenuates altered pain behaviour and prevents neuronal stress, possibly through an effect on TRPA1 activity. PMID:26201024

  4. Anti-diabetic molecules from Cycas pectinata Griff. traditionally used by the Maiba-Maibi.

    PubMed

    Laishram, S; Sheikh, Y; Moirangthem, D S; Deb, L; Pal, B C; Talukdar, N C; Borah, J C

    2015-01-15

    Bioactivity guided chemical investigation on active anti-diabetic constituents of the fruits of Cycas pectinata Griff. (FCP) characterized EAFr-5 as the most potent sub fraction which significantly reduced the blood glucose level to normal in STZ induced diabetic rats. It was shown to contain the biflavonoids amentoflavone (1) and 2,3-dihydroamentoflavone (2) which exhibited significantly high inhibitory potency against ?-glucosidase (IC50 8.090.023 and 9.770.032?M, respectively) and ?-amylase (IC50 73.60.48 and 39.690.39?M, respectively). This is the first report of bioactivity guided isolation of anti-diabetic constituents from the traditionally used fruits of Cycas pectinata Griff. PMID:25636866

  5. Effects of insulin-dependent diabetes mellitus on perforator-based flaps in streptozotocin diabetic rats.

    PubMed

    Serdaroglu, Ilhan; Islamoglu, Kemal; Ozgentas, Ege

    2005-01-01

    The purpose of this study was to investigate the effects of insulin-dependent diabetes mellitus (IDDM) on the viability of perforator-based flaps (pbf) in diabetic rats. Random-pattern flaps were also used as a control flap group. Wistar Albino rats, female, n = 60, were used. The study was done with four groups: Group 1 (diabetic rats, pbf), Group 2 (non-diabetic rats, pbf), Group 3 (diabetic rats, McFarlane flap), and Group 4 (non-diabetic rats, McFarlane flap). Streptozocin (STZ, 55 mg/kg) in a vehicle (sodium citrate, pH 4.5) was injected into the rats intraperitonally to create an IDDM model in the diabetic groups. Only the vehicle without STZ was injected into the rats intraperitonally in the non-diabetic groups. All flaps were elevated 10 weeks after injections. Measurements of the surviving areas of the flaps, and microangiographic and histopathologic studies were done 7 days after flap elevation. Blood glucose levels of the diabetic rats were significantly higher than those of the non-diabetic groups ( p < 0.001). The surviving flap areas were 41 +/- 21 percent in Group 1, 65 +/- 25 percent in Group 2, 49 +/- 10 percent in Group 3, and 66 +/- 10 percent in Group 4. The surviving flap areas of the diabetic groups were significantly less than those of the non-diabetic groups ( p < 0.001). Specific histopathologic changes of IDDM were seen only in the diabetic groups. Microangiographies in the diabetic and non-diabetic groups were very similar. The surviving flap areas of the perforator-based and random-pattern skin flaps in the diabetic rats were decreased by IDDM. If a flap is planned for diabetic wounds, it should be kept in mind that the area of flap necrosis may be larger than those of non-diabetics. PMID:15672321

  6. Diabetic Retinal and Choroidal Edema in SDT Rats

    PubMed Central

    Toyoda, Fumihiko; Shimmura, Machiko; Takano, Hiroko

    2016-01-01

    We evaluated the features of diabetic retinal and choroidal edema in Spontaneously Diabetic Torii (SDT) rats. We measured the retinal and choroidal thicknesses in normal Sprague-Dawley (SD) rats (n = 9) and SDT rats (n = 8). The eyes were enucleated 40 weeks later after they were diagnosed with diabetes, and 4-micron sections were cut for conventional histopathologic studies. The mean retinal and choroidal thicknesses were significantly thicker in the SDT rats than in the normal SD rats. The choroidal thickness was correlated strongly with the retinal thickness in both rat models. Diabetic retinopathy (DR) and diabetic choroidopathy appeared as edema in the SDT rats. The retinal thickness was correlated strongly with the choroidal thickness in the SDT rats, which is an ideal animal model of both DR and choroidopathy. PMID:26783535

  7. Pregabalin Attenuates Excitotoxicity in Diabetes

    PubMed Central

    Huang, Chin-Wei; Lai, Ming-Chi; Cheng, Juei-Tang; Tsai, Jing-Jane; Huang, Chao-Ching; Wu, Sheng-Nan

    2013-01-01

    Diabetes can exacerbate seizures and worsen seizure-related brain damage. In the present study, we aimed to determine whether the standard antiepileptic drug pregabalin (PGB) protects against pilocarpine-induced seizures and excitotoxicity in diabetes. Adult male Sprague-Dawley rats were divided into either a streptozotocin (STZ)-induced diabetes group or a normal saline (NS) group. Both groups were further divided into subgroups that were treated intravenously with either PGB (15 mg/kg) or a vehicle; all groups were treated with subcutaneous pilocarpine (60 mg/kg) to induce seizures. To evaluate spontaneous recurrent seizures (SRS), PGB-pretreated rats were fed rat chow containing oral PGB (450 mg) for 28 consecutive days; vehicle-pretreated rats were fed regular chow. SRS frequency was monitored for 2 weeks from post-status epilepticus day 15. We evaluated both acute neuronal loss and chronic mossy fiber sprouting in the CA3 area. In addition, we performed patch clamp recordings to study evoked excitatory postsynaptic currents (eEPSCs) in hippocampal CA1 neurons for both vehicle-treated rats with SRS. Finally, we used an RNA interference knockdown method for Kir6.2 in a hippocampal cell line to evaluate PGB's effects in the presence of high-dose ATP. We found that compared to vehicle-treated rats, PGB-treated rats showed less severe acute seizure activity, reduced acute neuronal loss, and chronic mossy fiber sprouting. In the vehicle-treated STZ rats, eEPSC amplitude was significantly lower after PGB administration, but glibenclamide reversed this effect. The RNA interference study confirmed that PGB could counteract the ATP-sensitive potassium channel (KATP)-closing effect of high-dose ATP. By opening KATP, PGB protects against neuronal excitotoxicity, and is therefore a potential antiepileptogenic in diabetes. These findings might help develop a clinical algorithm for treating patients with epilepsy and comorbid metabolic disorders. PMID:23785408

  8. Activation of spinal GABAB receptors normalizes N-methyl-D-aspartate receptor in diabetic neuropathy.

    PubMed

    Bai, Hui-Ping; Liu, Peng; Wu, Yu-Ming; Guo, Wen-Ya; Guo, Yue-Xian; Wang, Xiu-Li

    2014-06-15

    N-methyl-D-aspartate receptor (NMDAR) activity is increased, while GABAB receptor is downregulated in the spinal cord dorsal horn in diabetic neuropathy. In this study, we determined the interaction of NMDARs and GABAB receptors in streptozotocin (STZ)-induced diabetic neuropathy. The paw withdrawal threshold (PWT) was significantly lower in STZ-treated rats than in vehicle-treated rats. Intrathecal injection of baclofen, a GABAB receptor agonist, significantly increased the PWT in STZ-treated rats, an effect that was abolished by pre-administration of the GABAB receptor specific antagonist CGP55845. Spinal NR2B, an NMDA receptor subunit, protein and mRNA expression levels were significantly higher in STZ-treated rats than in vehicle-treated rats. Intrathecal baclofen significantly reduced the NR2B protein and mRNA expression levels in STZ-treated rats. Intrathecal administration of CGP55845 eliminated baclofen-induced reduction of NR2B protein and mRNA levels in STZ-treated rats. In addition, the phosphorylated cAMP response element-binding (CREB) protein level was significantly higher in the spinal cord dorsal horn in STZ-treated rats compared with vehicle-treated rats. Intrathecal injection of baclofen significantly decreased phosphorylated CREB protein level in STZ-treated rats; an effect was blocked by CGP55845. These data suggest that activation of GABAB receptors in the spinal cord dorsal horn normalizes NMDAR expression level in diabetic neuropathic pain. PMID:24787504

  9. Oxidative stress status accompanying diabetic bladder cystopathy results in the activation of protein degradation pathways

    PubMed Central

    Kanika, Nirmala; Chang, Jinsook; Tong, Yuehong; Tiplitsky, Scott; Lin, Juan; Yohannes, Elizabeth; Tar, Moses; Chance, Mark; Christ, George J.; Melman, Arnold; Davies, Kelvin

    2010-01-01

    Objectives To investigate the role that oxidative stress plays in the development of diabetic cystopathy. Materials and methods Comparative gene expression in the bladder of non-diabetic and streptozotocin (STZ)-induced 2-month-old diabetic rats was carried out using microarray analysis. Evidence of oxidative stress was investigated in the bladder by analyzing glutathione S-transferase activity, lipid peroxidation, and carbonylation and nitrosylation of proteins. The activity of protein degradation pathways was assessed using western blot analysis. Results Analysis of global gene expression showed that detrusor smooth muscle tissue of STZ-induced diabetes undergoes significant enrichment in targets involved in the production or regulation of reactive oxygen species (P = 1.27 10?10). The microarray analysis was confirmed by showing that markers of oxidative stress were all significantly increased in the diabetic bladder. It was hypothesized that the sequelae to oxidative stress would be increased protein damage and apoptosis. This was confirmed by showing that two key proteins involved in protein degradation (Nedd4 and LC3B) were greatly up-regulated in diabetic bladders compared to controls by 12.2 0.76 and 4.4 1.0-fold, respectively, and the apoptosis inducing protein, BAX, was up-regulated by 6.76 0.76-fold. Conclusions Overall, the findings obtained in the present study add to the growing body of evidence showing that diabetic cystopathy is associated with oxidative damage of smooth muscle cells, and results in protein damage and activation of apoptotic pathways that may contribute to a deterioration in bladder function. PMID:21518418

  10. Antidiabetic Effects of Yam (Dioscorea batatas) and Its Active Constituent, Allantoin, in a Rat Model of Streptozotocin-Induced Diabetes

    PubMed Central

    Go, Hyeon-Kyu; Rahman, Md. Mahbubur; Kim, Gi-Beum; Na, Chong-Sam; Song, Choon-Ho; Kim, Jin-Shang; Kim, Shang-Jin; Kang, Hyung-Sub

    2015-01-01

    The objective of this study was to investigate the therapeutic efficacies of crude yam (Dioscorea batatas) powder (PY), water extract of yam (EY), and allantoin (the active constituent of yam) in streptozotocin (STZ)-induced diabetic rats with respect to glucose, insulin, glucagon-like peptide-1 (GLP-1), C-peptide, glycated hemoglobin (HbAlc), lipid metabolism, and oxidative stress. For this purpose, 50 rats were divided into five groups: normal control (NC), diabetic control (STZ), and STZ plus treatment groups (STZ + PY, STZ + EY, and STZ + allantoin). After treatment for one-month, there was a decrease in blood glucose: 385 ± 7 in STZ, 231 ± 3 in STZ + PY, 214 ± 11 in STZ + EY, and 243 ± 6 mg/dL in STZ + allantoin, respectively. There were significant statistical differences (p < 0.001) compared to STZ (100%): 60% in STZ + PY, 55% in STZ + EY, and 63% in STZ + allantoin. With groups in the same order, there were significant decreases (p < 0.001) in HbAlc (100% as 24.4 ± 0.6 ng/mL, 78%, 75%, and 77%), total cholesterol (100% as 122 ± 3 mg/dL, 70%, 67%, and 69%), and low-density lipoprotein (100% as 29 ± 1 mg/dL, 45%, 48%, and 38%). There were also significant increases (p < 0.001) in insulin (100% as 0.22 ± 0.00 ng/mL, 173%, 209%, and 177%), GLP-1 (100% as 18.4 ± 0.7 pmol/mL, 160%, 166%, and 162%), and C-peptide (100% as 2.56 ± 0.10 ng/mL, 129%, 132%, and 130%). The treatment effectively ameliorated antioxidant stress as shown by a significant decrease (p < 0.001) in malondialdehyde (100% as 7.25 ± 0.11 nmol/mL, 87%, 86%, and 85%) together with increases (p < 0.01) in superoxide dismutase (100% as 167 ± 6 IU/mL, 147%, 159%, and 145%) and reduced glutathione (100% as 167 ± 6 nmol/mL, 123%, 141%, and 140%). The results indicate that yam and allantoin have antidiabetic effects by modulating antioxidant activities, lipid profiles and by promoting the release of GLP-1, thereby improving the function of β-cells maintaining normal insulin and glucose levels. PMID:26501316

  11. Antidiabetic Effects of Yam (Dioscorea batatas) and Its Active Constituent, Allantoin, in a Rat Model of Streptozotocin-Induced Diabetes.

    PubMed

    Go, Hyeon-Kyu; Rahman, Md Mahbubur; Kim, Gi-Beum; Na, Chong-Sam; Song, Choon-Ho; Kim, Jin-Shang; Kim, Shang-Jin; Kang, Hyung-Sub

    2015-10-01

    The objective of this study was to investigate the therapeutic efficacies of crude yam (Dioscorea batatas) powder (PY), water extract of yam (EY), and allantoin (the active constituent of yam) in streptozotocin (STZ)-induced diabetic rats with respect to glucose, insulin, glucagon-like peptide-1 (GLP-1), C-peptide, glycated hemoglobin (HbAlc), lipid metabolism, and oxidative stress. For this purpose, 50 rats were divided into five groups: normal control (NC), diabetic control (STZ), and STZ plus treatment groups (STZ + PY, STZ + EY, and STZ + allantoin). After treatment for one-month, there was a decrease in blood glucose: 385 ± 7 in STZ, 231 ± 3 in STZ + PY, 214 ± 11 in STZ + EY, and 243 ± 6 mg/dL in STZ + allantoin, respectively. There were significant statistical differences (p < 0.001) compared to STZ (100%): 60% in STZ + PY, 55% in STZ + EY, and 63% in STZ + allantoin. With groups in the same order, there were significant decreases (p < 0.001) in HbAlc (100% as 24.4 ± 0.6 ng/mL, 78%, 75%, and 77%), total cholesterol (100% as 122 ± 3 mg/dL, 70%, 67%, and 69%), and low-density lipoprotein (100% as 29 ± 1 mg/dL, 45%, 48%, and 38%). There were also significant increases (p < 0.001) in insulin (100% as 0.22 ± 0.00 ng/mL, 173%, 209%, and 177%), GLP-1 (100% as 18.4 ± 0.7 pmol/mL, 160%, 166%, and 162%), and C-peptide (100% as 2.56 ± 0.10 ng/mL, 129%, 132%, and 130%). The treatment effectively ameliorated antioxidant stress as shown by a significant decrease (p < 0.001) in malondialdehyde (100% as 7.25 ± 0.11 nmol/mL, 87%, 86%, and 85%) together with increases (p < 0.01) in superoxide dismutase (100% as 167 ± 6 IU/mL, 147%, 159%, and 145%) and reduced glutathione (100% as 167 ± 6 nmol/mL, 123%, 141%, and 140%). The results indicate that yam and allantoin have antidiabetic effects by modulating antioxidant activities, lipid profiles and by promoting the release of GLP-1, thereby improving the function of β-cells maintaining normal insulin and glucose levels. PMID:26501316

  12. Protective effects of Annona muricata Linn. (Annonaceae) leaf aqueous extract on serum lipid profiles and oxidative stress in hepatocytes of streptozotocin-treated diabetic rats.

    PubMed

    Adewole, Stephen O; Ojewole, John A O

    2008-01-01

    Extracts from various morphological parts of Annona muricata Linn. (Annonaceae) are widely used medicinally in many parts of the world for the management, control and/or treatment of a plethora of human ailments, including diabetes mellitus (DM). The present study was undertaken to investigate the possible protective effects of A. muricata leaf aqueous extract (AME) in rat experimental paradigms of DM. The animals used were broadly divided into four (A, B, C and D) experimental groups. Group A rats served as 'control' animals and received distilled water in quantities equivalent to the administered volumes of AME and reference drugs' solutions intraperitoneally. Diabetes mellitus was induced in Groups B and C rats by intraperitoneal injections of streptozotocin (STZ, 70 mg kg(-1)). Group C rats were additionally treated with AME (100 mg kg(-1) day(-1), p.o.) as from day 3 post STZ injection, for four consecutive weeks. Group D rats received AME (100 mg kg(-1) day(-1) p.o.) only for four weeks. Post-euthanization, hepatic tissues were excised and processed biochemically for antioxidant enzymes and lipid profiles, such as catalase (CAT), reactive oxygen species (ROS), glutathione (GSH), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), thiobarbituric acid reactive substances (TBARS), triglycerides (TG), total cholesterol (TC), high density lipoprotein (HDL) and low density lipoprotein (LDL), respectively. Treatment of Groups B and C rats with STZ (70 mg kg(-1) i. p.) resulted in hyperglycaemia, hypoinsulinaemia, and increased TBARS, ROS, TC, TG and LDL levels. STZ treatment also significantly decreased (p<0.05) CAT, GSH, SOD, GSH-Px activities, and HDL levels. AME-treated Groups C and D rats showed significant decrease (p<0.05) in elevated blood glucose, ROS, TBARS, TC, TG and LDL. Furthermore, AME treatment significantly increased (p<0.05) antioxidant enzymes' activities, as well as serum insulin levels. The findings of this laboratory animal study suggest that A. muricata extract has a protective, beneficial effect on hepatic tissues subjected to STZ-induced oxidative stress, possibly by decreasing lipid peroxidation and indirectly enhancing production of insulin and endogenous antioxidants. PMID:20162039

  13. Genetic Difference in Susceptibility to the Blood-Retina Barrier Breakdown in Diabetes and Oxygen-Induced Retinopathy

    PubMed Central

    Zhang, Sarah X.; Ma, Jian-xing; Sima, Jing; Chen, Ying; Hu, Mark S.; Ottlecz, Anna; Lambrou, George N.

    2005-01-01

    The breakdown of the blood-retina barrier (BRB) is a common feature of diabetic retinopathy. The purpose of the present study is to determine whether there are genetic differences in susceptibility to the breakdown of the BRB in diabetic retinopathy using two rat models. In streptozotocin (STZ)-induced diabetes, Brown Norway (BN) rats developed sustained vascular hyperpermeability in the retina during the entire experimental period (16 weeks of diabetes), while diabetic Sprague Dawley (SD) rats only showed retinal hyperpermeability from 3 to 10 days after the onset of diabetes. The strain difference in permeability was not correlated with the blood glucose levels in these two strains. In oxygen-induced retinopathy (OIR), BN rats developed retinal vascular hyperpermeability from postnatal day 12 (P12) to P22 with a peak at P16, which was 8.7-fold higher than that in the age-matched normal controls. In OIR-SD rats, however, hyperpermeability was observed from P14 to P18, with a peak only 2.2-fold higher than that in the controls. The strain difference in vascular hyperpermeability was correlated with the different overexpression of vascular endothelial growth factor (VEGF) in the retina of these two models. This finding suggests that genetic backgrounds contribute to the susceptibility to diabetic retinopathy. PMID:15632023

  14. Boldine Prevents Renal Alterations in Diabetic Rats

    PubMed Central

    Hernndez-Salinas, Romina; Vielma, Alejandra Z.; Arismendi, Marlene N.; Boric, Mauricio P.; Sez, Juan C.; Velarde, Victoria

    2013-01-01

    Diabetic nephropathy alters both structure and function of the kidney. These alterations are associated with increased levels of reactive oxygen species, matrix proteins, and proinflammatory molecules. Inflammation decreases gap junctional communication and increases hemichannel activity leading to increased membrane permeability and altering tissue homeostasis. Since current treatments for diabetic nephropathy do not prevent renal damage, we postulated an alternative treatment with boldine, an alkaloid obtained from boldo with antioxidant, anti-inflammatory, and hypoglycemic effects. Streptozotocin-induced diabetic and control rats were treated or not treated with boldine (50?mg/Kg/day) for ten weeks. In addition, mesangial cells were cultured under control conditions or in high glucose concentration plus proinflammatory cytokines, with or without boldine (100?mol/L). Boldine treatment in diabetic animals prevented the increase in glycemia, blood pressure, renal thiobarbituric acid reactive substances and the urinary protein/creatinine ratio. Boldine also reduced alterations in matrix proteins and markers of renal damage. In mesangial cells, boldine prevented the increase in oxidative stress, the decrease in gap junctional communication, and the increase in cell permeability due to connexin hemichannel activity induced by high glucose and proinflammatory cytokines but did not block gap junction channels. Thus boldine prevented both renal and cellular alterations and could be useful for preventing tissue damage in diabetic subjects. PMID:24416726

  15. Effects of alpha lipoic acid, ascorbic acid-6-palmitate, and fish oil on the glutathione, malonaldehyde, and fatty acids levels in erythrocytes of streptozotocin induced diabetic male rats.

    PubMed

    Yilmaz, Okke?; Ozkan, Yusuf; Yildirim, Mehmet; Oztrk, A Ihsan; Er?an, Yasemin

    2002-01-01

    In this research, it has been aimed to evaluate the improvement effects of alpha lipoic acid (ALA), ascorbic acid-6-palmitate (AA6P), fish oil (FO), and their combination (COM) on some biochemical properties in erythrocytes of streptozotocin (STZ)-induced diabetic male rats. According to experimental results, glutathione (GSH) level in erythrocytes decreased in diabetes (P < 0.01), D + ALA, and D + AA6P groups (P < 0.001). Malonaldehyde (MA) level increased in diabetes (P < 0.05), D + FO, and D + COM groups (P < 0.001), but its level in D + AA6P and D + ALA groups was lower in diabetes group (P < 0.01). Total lipid level in diabetes and diabetes plus antioxidant administered groups were higher than control. Total cholesterol level was high in diabetes and D + ALA groups (P < 0.05), but its level reduced in D + FO compared to control and diabetes groups, P < 0.05, < 0.001, respectively. Total triglyceride (TTG) level was high in the D + ALA (P < 0.05) and D + COM (P < 0.001) groups. In contrast, TTG level in blood of diabetes group was higher than diabetes plus antioxidant and FO administered groups (P < 0.001). According to gas chromatography analysis results, while the palmitic acid raised in diabetes group (P < 0.05), stearic acid in D + FO, D + ALA, and diabetes groups was lower than control (P < 0.05), oleic acid reduced in D + COM and D + FO groups, but its level raised in D + AA6P and D + ALA groups (P < 0.01). As the linoleic acid (LA) elevated in ALA + D, D + AA6P, and diabetes groups, linolenic acid level in diabetes, D + AA6P, and D + FO groups was lower than control (P < 0.001). Arachidonic acid (AA) decreased in D + ALA, D+ AA6P, and diabetes groups (P < 0.01), but its level in D + COM and D + FO was higher than control (P < 0.05). Docosahexaenoic acid (DHA) increased in D + AA6P and D + COM (P < 0.05). While the total saturated fatty acid level raised in diabetes group, its level reduced in D + ALA and D + FO groups (P < 0.05). In contrast, total unsaturated fatty acid level in D + ALA and D + FO groups was higher than control (P < 0.05). In conclusion, present data have confirmed that the combination of the ALA, AA6P, and FO have improvement effects on the recycling of GSSG to reduced GSH in erythrocytes of diabetic rats, and in addition to this, oxidative stress was suppressed by ALA and AA6P, and unsaturated fatty acid degree was raised by the effects of ALA and FO. PMID:12210759

  16. Gabapentin prevents hyperalgesia during the formalin test in diabetic rats.

    PubMed

    Cesea, R M; Calcutt, N A

    1999-03-01

    The anticonvulsant agent gabapentin exhibits antihyperalgesic properties in animal models of neuropathic pain. Diabetic rats display increased nocifensive behavior during the formalin test of persistent chemical irritation to the paw, suggesting the presence of abnormal pain processing mechanisms. We therefore, investigated the efficacy of gabapentin on formalin-evoked behavior in diabetic rats. Diabetic rats showed increased (P < 0.05) flinching during the normally quiescent phase of the 5.0% formalin test. Gabapentin (50 mg/kg i.p. 30 min pre-test) suppressed flinching during phases 1 and 2 of the formalin test in both control and diabetic rats but not the increased flinching of diabetic rats during the quiescent phase. When 0.5% formalin was used, diabetic rats exhibited increased flinching during both the quiescent phase and phase 2. Gabapentin was without effect in controls but suppressed (P < 0.01) the increased flinching in diabetic rats. Gabapentin displays efficacy against abnormal sensory processing in diabetic rats and may be of benefit for treating painful diabetic neuropathy. PMID:10203241

  17. Adipocyte dysfunction in rats with streptozotocinnicotinamide-induced diabetes

    PubMed Central

    Szkudelska, Katarzyna; Nogowski, Leszek; Szkudelski, Tomasz

    2014-01-01

    Administration of streptozotocin (STZ) and nicotinamide (NA) to adult rats allows for the induction of mild diabetes. However, this experimental model has not been fully characterized. This study was undertaken to determine the metabolic and secretory activity of adipose tissue in rats with STZ-NA-induced diabetes. Experiments were performed using epididymal adipocytes isolated from control and mildly diabetic rats. Lipogenesis, glucose transport as well as glucose and alanine oxidation, lipolysis, anti-lipolysis, cAMP levels and adipokine secretion were compared in cells isolated from the control and diabetic rats. Lipogenesis, glucose transport and oxidation were diminished in the adipocytes of diabetic rats compared with the fat cells of control animals. However, alanine oxidation appeared to be similar in the cells of non-diabetic and diabetic animals. Lipolytic response to low epinephrine concentrations was slightly increased in the adipocytes of diabetic rats; however, at higher concentrations of the hormone, lipolysis was similar in both groups of cells. The epinephrine-induced rise in cAMP levels was higher in the adipocytes of STZ-NA-induced diabetic rats, even in the presence of insulin. Lipolysis stimulated by dibutyryl-cAMP did not significantly differ, whereas anti-lipolytic effects of insulin were mildly decreased in the cells of diabetic rats. Secretion of adiponectin and leptin was substantially diminished in the adipocytes of diabetic rats compared with the cells of control animals. Our studies demonstrated that the balance between lipogenesis and lipolysis in the adipose tissue of rats with mild diabetes induced by STZ and NA is slightly shifted towards reduced lipid accumulation. Simultaneously, adiponectin and leptin secretion is significantly impaired. PMID:24628786

  18. Discovery of Potent and Orally Active Lipoprotein-Associated Phospholipase A2 (Lp-PLA2) Inhibitors as a Potential Therapy for Diabetic Macular Edema.

    PubMed

    Chen, Xinde; Wang, Kai; Xu, Wenwei; Ma, Quanxin; Chen, Minli; Du, Lili; Mo, Mingguang; Wang, Yiping; Shen, Jianhua

    2016-03-24

    Lipoprotein-associated phospholipase A2 (Lp-PLA2) is considered to be a promising therapeutic target for several inflammation-associated diseases. Herein, we describe the discovery of a series of pyrimidone derivatives as Lp-PLA2 inhibitors. Systematic structural modifications led to the identification of several pyrimidone compounds with promising in vitro inhibitory potency and pharmacokinetic properties. Compound 14c, selected for in vivo evaluation, demonstrated decent pharmacokinetic profiles and robust inhibitory potency against Lp-PLA2 in Sprague-Dawley (SD) rats. Furthermore, 14c significantly inhibited retinal thickening in STZ-induced diabetic SD rats as a model of diabetic macular edema (DME) after oral dosing for 4 weeks. Taken together, these results suggested that 14c can serve as a valuable lead in the search for new Lp-PLA2 inhibitors for prevention and/or treatment of DME. PMID:26927682

  19. Synthesis and SAR study of new thiazole derivatives as vascular adhesion protein-1 (VAP-1) inhibitors for the treatment of diabetic macular edema.

    PubMed

    Inoue, Takayuki; Morita, Masataka; Tojo, Takashi; Yoshihara, Kousei; Nagashima, Akira; Moritomo, Ayako; Ohkubo, Mitsuru; Miyake, Hiroshi

    2013-03-01

    Vascular adhesion protein-1 (VAP-1), an amine oxidase that is also known as a semicarbazide-sensitive amine oxidase (SSAO), is present in particularly high levels in human plasma, and is considered a potential therapeutic target for various inflammatory diseases, including diabetes complications such as macular edema. In our VAP-1 inhibitor program, structural modifications following high-throughput screening (HTS) of our compound library resulted in the discovery that thiazole derivative 10, which includes a guanidine group, shows potent human VAP-1 inhibitory activity (IC(50) of 230 nM; rat IC(50) of 14 nM). Moreover, compound 10 exhibited significant inhibitory effects on ocular permeability in STZ-induced diabetic rats. PMID:23337801

  20. Naringin Alleviates Diabetic Kidney Disease through Inhibiting Oxidative Stress and Inflammatory Reaction

    PubMed Central

    Chen, Fenqin; Zhang, Ning; Ma, Xiaoyu; Huang, Ting; Shao, Ying; Wu, Can; Wang, Qiuyue

    2015-01-01

    Naringin, a flavanone glycoside extracted from Citrus grandis Osbeck, has a wide range of pharmacological effects. In the present study we aimed at demonstrating the protective effect of naringin against diabetic kidney disease (DKD) and elucidating its possible molecular mechanism underlying. The beneficial effect of naringin was assessed in rats with streptozotocin (STZ)-induced diabetes and high glucose-induced HBZY-1 cells. According to our results, first we found that naringin relieved kidney injury, improved renal function and inhibited collagen formation and renal interstitial fibrosis. Second, we confirmed that naringin restrained oxidative stress by activating Nrf2 antioxidant pathway. Moreover, the results suggested that naringin significantly resisted inflammatory reaction by inhibiting NF- κ B signaling pathway. Taken together, our results demonstrate that naringin effectively alleviates DKD, which provide theoretical basis for naringin clinically used to treatment of DKD. PMID:26619044

  1. Pterostilbene Ameliorates Streptozotocin-Induced Diabetes through Enhancing Antioxidant Signaling Pathways Mediated by Nrf2.

    PubMed

    Elango, Bhakkiyalakshmi; Dornadula, Sireesh; Paulmurugan, Ramasamy; Ramkumar, Kunka Mohanram

    2016-01-19

    Nuclear factor erythroid 2-related factor 2 (Nrf2) remains a master regulator of cytoprotective and antioxidant genes. In this study, we investigated the antidiabetic role of pterostilbene (PTS) in streptozotocin (STZ)-induced diabetic model through Nrf2-mediated antioxidant mechanisms. The ability of PTS to activate Nrf2 in MIN6 cells was assessed by dissociation of the Nrf2-Keap1 complex at different time points and by expression of ARE-driven downstream target genes of Nrf2. Immunoblot experiments examining Nrf2 activation and phosphorylation indicated that it conferred cytoprotection against STZ-induced cellular damage. In STZ-induced diabetic mice, PTS administration significantly decreased blood glucose levels through the improvement of insulin secretion. In addition, we also observed insulin-positive cells with recovered islet architecture in the pancreas of STZ-induced diabetic mice after treatment with PTS. The activation of Nrf2 and expression of its downstream target genes were observed upon PTS treatment, thereby reducing oxidative damage to pancreas. Furthermore, PTS treatment significantly reverted the abundance of key glucose metabolism enzymes, such as hexokinase, glucose-6-phosphatase, glucose-6-phosphate dehydrogenase, and fructose-1,6-bisphosphatase, to near-normal levels in liver tissue of STZ-induced diabetic mice. These results clearly indicate that PTS maintains glucose homeostasis, suggesting the possibility that it is a future candidate for use in diabetes management. PMID:26700463

  2. Antihyperglycaemic effect of 'Ilogen-Excel', an ayurvedic herbal formulation in streptozotocin-induced diabetes mellitus.

    PubMed

    Umamaheswari, Selvaraj; Mainzen Prince, Ponnaian Stanely

    2007-01-01

    'Ilogen-Excel', an Ayurvedic herbal formulation is composed of eight medicinal plants (Curcuma longa, Strychnos potatorum, Salacia oblonga, Tinospora cordifolia, Vetivelia zizanioides, Coscinium fenestratum, Andrographis paniculata and Mimosa pudica). The present study evaluates the antihyperglycemic effect of 'Ilogen-Excel' in streptozotocin induced diabetic rats. Rats were rendered diabetic by streptozotocin (STZ) (45 mg/kg body weight). Oral administration of 'Ilogen-Excel' (50 mg/kg and 100 mg/kg) for 60 days resulted in significantly lowered levels of blood glucose and significantly increased levels of plasma insulin, hepatic glycogen and total hemoglobin. 'Ilogen-Excel' administration also decreased the levels of glycosylated hemoglobin, plasma thiobarbituric acid reactive substances, hydroperoxides, ceruloplasmin and vitamin E in diabetic rats. Plasma reduced glutathione and vitamin C were significantly elevated by oral administration of 'Ilogen-Excel'. Administration of insulin normalized all the biochemical parameters studied in diabetic rats. The effect at a dose of 100 mg/kg was more pronounced than 50 mg/kg and brought back all the parameters to near normal levels. Thus, our study shows the antihyperglycemic effects of 'Ilogen-Excel' in STZ-induced diabetic rats. Our study also shows that combined therapy is better than individual therapy. PMID:17665851

  3. Role of hydrogen sulfide in the pain processing of non-diabetic and diabetic rats.

    PubMed

    Velasco-Xolalpa, M E; Barragn-Iglesias, P; Roa-Coria, J E; Godnez-Chaparro, B; Flores-Murrieta, F J; Torres-Lpez, J E; Araiza-Saldaa, C I; Navarrete, A; Rocha-Gonzlez, H I

    2013-10-10

    Hydrogen sulfide (H2S) is a gasotransmitter endogenously generated from the metabolism of L-cysteine by action of two main enzymes called cystathionine ?-synthase (CBS) and cystathionine ?-lyase (CSE). This gas has been involved in the pain processing and insulin resistance produced during diabetes development. However, there is no evidence about its participation in the peripheral neuropathy induced by this metabolic disorder. Experimental diabetes was induced by streptozotocin (50mg/kg, i.p.) in female Wistar rats. Streptozotocin injection increased formalin-evoked flinching in diabetic rats as compared to non-diabetic rats after 2 weeks. Peripheral administration of NaHS (an exogenous donor of H2S) and L-cysteine (an endogenous donor of H2S) dose-dependently increased flinching behavior in diabetic and non-diabetic rats. Contrariwise, hydroxylamine (HA, a CBS inhibitor) and DL-propargylglycine (PPG, a CSE inhibitor) decreased formalin-induced nociceptive behavior in both experimental groups. In addition, an ineffective dose of HA and PPG partially prevented the L-cysteine-induced hyperalgesia in diabetic and non-diabetic rats. Interestingly, HA and PPG were three order of magnitude more potent in diabetic rats respect to non-diabetic rats, whereas NaHS was ten times more potent in the streptozotocin-diabetic group. Nine to 11 weeks after diabetes induction, tactile allodynia was observed in the streptozotocin-injected rats. On this condition, subcutaneous administration of PPG or HA reduced tactile allodynia in diabetic rats. Paradoxically, H2S levels were decreased in nerve sciatic, dorsal root ganglion and spinal cord, but not paw nor blood plasma, during diabetes-associated peripheral neuropathy development. Collectively, results suggest that H2S synthesized by CBS and CSE participate in formalin-induced nociception in diabetic and non-diabetic rats, as well as; in tactile allodynia in streptozotocin-injected rats. In addition, data seems to indicate that diabetic rats are more sensible to H2S-induced hyperalgesia than normoglycemic rats. PMID:23830907

  4. Improvement of diabetic complication by hydrangea dulcis folium in streptozotocin-induced diabetic rats.

    PubMed

    Kim, Hye Kyung; Kim, Mi Jeong; Lyu, Eun Soon; Shin, Dong-Hoon

    2009-01-01

    The improvement of diabetic complications such as lipid lowering and anti-oxidative potential of Hydrangea Dulcis Folium (HDF) was studied in streptozotocin-induced diabetic rats. Male Sprague-Dawley rats were divided into 3 groups after induction of streptozotocin (STZ)-diabetes: normal control; diabetic control; diabetic-HDF supplement (hot water extract 40 g/kg diet); and fed experimental diets for 3 weeks. Serum glucose and insulin concentrations, serum lipid profile, intraperitoneal glucose tolerance test, and liver cytosolic antioxidant enzyme levels were measured. The HDF supplement significantly decreased serum glucose concentration, increased insulin level, and improved glucose homeostasis in diabetic control rats. The total cholesterol and triglyceride concentrations in the serum and liver were markedly reduced by HDF treatment in STZ-diabetic rats. Moreover, low density lipoprotein (LDL)-, VLDL-, and high density lipoprotein (HDL)-cholesterol levels were ameliorated in HDF supplemented diabetic rats. Decreased fecal excretions of cholesterol, triglyceride, and bile acid in diabetic rats were significantly increased by HDF consumption. HDF supplement reversed the effects of the oxidative stress system of liver in diabetic rats. Lipid peroxidation of diabetic rats, assessed by thiobarbituric acid reactive substance (TBARS), as well as superoxide dismutase (SOD) activities were significantly increased, and glutathione contents were decreased in diabetic rats. HDF supplement reverted these parameters to near normal value. Our data suggest that HDF supplement could be used to improve the glucose and lipid metabolism as well as to reduce the imbalance between the generation of reactive oxygen species (ROS) and the scavenging enzyme activity in preventing diabetic complications. PMID:19122300

  5. Effects of ferulic acid on diabetic nephropathy in a rat model of type 2 diabetes

    PubMed Central

    Choi, Ran; Kim, Bo Hwan; Naowaboot, Jarinyaporn; Lee, Mi Young; Hyun, Mi Ri; Cho, Eun Ju; Lee, Eun Soo; Lee, Eun Young; Yang, Young Chul

    2011-01-01

    Diabetic nephropathy is the most serious complication in diabetes mellitus. It is known that oxidative stress and inflammation play a central role in the development of diabetic nephropathy. In this study, we investigated that ferulic acid (FA) known as anti-oxidative agent could effect on diabetic nephropathy by anti-oxidative and anti-inflammatory mechanism. We examined the effects of FA in obese diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats and non-diabetic control Long-Evans Tokushima Otsuka (LETO) rats. We treated FA to experimental rats from 26 to 45 weeks of age. We evaluated ACR, MDA and MCP-1 in 24 h urine and examined renal histopathology and morphologic change in extracted kidneys from rats. Also, we evaluated the ROS production and MCP-1 levels in cultured podocyte after FA treatment. In the FA-treated OLETF rats, blood glucose was significantly decreased and serum adiponectin levels were increased. Urinary ACR was significantly reduced in FA-treated OLETF rats compared with diabetic OLETF rats. In renal histopathology, FA-treated OLETF rats showed decreased glomerular basement membrane thickness, glomerular volume, and mesangial matrix expansion. FA treatment decreased oxidative stress markers and MCP-1 levels in 24 h urine of rats and supernatants of cultured podocyte. In conclusion, it was suggested that FA have protective and therapeutic effects on diabetic nephropathy by reducing oxidative stress and inflammation. PMID:21975281

  6. Carbonylation Contributes to SERCA2a Activity Loss and Diastolic Dysfunction in a Rat Model of Type 1 Diabetes

    PubMed Central

    Shao, Chun Hong; Capek, Haley L.; Patel, Kaushik P.; Wang, Mu; Tang, Kang; DeSouza, Cyrus; Nagai, Ryoji; Mayhan, William; Periasamy, Muthu; Bidasee, Keshore R.

    2011-01-01

    OBJECTIVE Approximately 25% of children and adolescents with type 1 diabetes will develop diastolic dysfunction. This defect, which is characterized by an increase in time to cardiac relaxation, results in part from a reduction in the activity of the sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA2a), the ATP-driven pump that translocates Ca2+ from the cytoplasm to the lumen of the sarcoplasmic reticulum. To date, mechanisms responsible for SERCA2a activity loss remain incompletely characterized. RESEARCH DESIGN AND METHODS The streptozotocin (STZ)-induced murine model of type 1 diabetes, in combination with echocardiography, high-speed video detection, confocal microscopy, ATPase and Ca2+ uptake assays, Western blots, mass spectrometry, and site-directed mutagenesis, were used to assess whether modification by reactive carbonyl species (RCS) contributes to SERCA2a activity loss. RESULTS After 67 weeks of diabetes, cardiac and myocyte relaxation times were prolonged. Total ventricular SERCA2a protein remained unchanged, but its ability to hydrolyze ATP and transport Ca2+ was significantly reduced. Western blots and mass spectroscopic analyses revealed carbonyl adducts on select basic residues of SERCA2a. Mutating affected residues to mimic physio-chemical changes induced on them by RCS reduced SERCA2a activity. Preincubating with the RCS, methylglyoxal (MGO) likewise reduced SERCA2a activity. Mutating an impacted residue to chemically inert glutamine did not alter SERCA2a activity, but it blunted MGO's effect. Treating STZ-induced diabetic animals with the RCS scavenger, pyridoxamine, blunted SERCA2a activity loss and minimized diastolic dysfunction. CONCLUSIONS These data identify carbonylation as a novel mechanism that contributes to SERCA2a activity loss and diastolic dysfunction during type 1 diabetes. PMID:21300842

  7. Bone morphological analyses in Spontaneously Diabetic Torii (SDT) fatty rats

    PubMed Central

    OHTA, Takeshi; KIMURA, Shuichi; HIRATA, Masaya; YAMADA, Takahisa; SUGIYAMA, Toshie

    2015-01-01

    The Spontaneously Diabetic Torii (SDT) fatty rat, a model for obese type 2 diabetes, shows bone quantitative abnormalities, namely low bone mineral density (BMD). The objective of this study was to evaluate bone morphological changes, in particular identifying the bone qualitative abnormalities, in the SDT fatty rat. Male SDT fatty rats showed increases in total trabecular area and trabecular number and decreases in trabecular thickness in cancellous bones of the proximal tibia, indicating trabecular miniaturization. The SDT fatty rat is useful for investigation of pathophysiological changes in bone quality in diabetic osteoporosis. PMID:26004433

  8. Histone deacetylase-2 is a key regulator of diabetes- and transforming growth factor-beta1-induced renal injury.

    PubMed

    Noh, Hyunjin; Oh, Eun Young; Seo, Ji Yeon; Yu, Mi Ra; Kim, Young Ok; Ha, Hunjoo; Lee, Hi Bahl

    2009-09-01

    Excessive accumulation of extracellular matrix (ECM) in the kidneys and epithelial-to-mesenchymal transition (EMT) of renal tubular epithelial cells contributes to the renal fibrosis that is associated with diabetic nephropathy. Histone deacetylase (HDAC) determines the acetylation status of histones and thereby controls the regulation of gene expression. This study examined the effect of HDAC inhibition on renal fibrosis induced by diabetes or transforming growth factor (TGF)-beta1 and determined the role of reactive oxygen species (ROS) as mediators of HDAC activation. In streptozotocin (STZ)-induced diabetic kidneys and TGF-beta1-treated normal rat kidney tubular epithelial cells (NRK52-E), we found that trichostatin A, a nonselective HDAC inhibitor, decreased mRNA and protein expressions of ECM components and prevented EMT. Valproic acid and class I-selective HDAC inhibitor SK-7041 also showed similar effects in NRK52-E cells. Among the six HDACs tested (HDAC-1 through -5 and HDAC-8), HDAC-2 activity significantly increased in the kidneys of STZ-induced diabetic rats and db/db mice and TGF-beta1-treated NRK52-E cells. Levels of mRNA expression of fibronectin and alpha-smooth muscle actin were decreased, whereas E-cadherin mRNA was increased when HDAC-2 was knocked down using RNA interference in NRK52-E cells. Interestingly, hydrogen peroxide increased HDAC-2 activity, and the treatment with an antioxidant, N-acetylcysteine, almost completely reduced TGF-beta1-induced activation of HDAC-2. These findings suggest that HDAC-2 plays an important role in the development of ECM accumulation and EMT in diabetic kidney and that ROS mediate TGF-beta1-induced activation of HDAC-2. PMID:19553350

  9. Cannabinoid functions in the amygdala contribute to conditioned fear memory in streptozotocin-induced diabetic mice: Interaction with glutamatergic functions.

    PubMed

    Ikeda, Hiroko; Ikegami, Megumi; Kai, Misa; Kamei, Junzo

    2015-07-01

    The role of cannabinoid systems in conditioned fear memory was investigated in streptozotocin (STZ)-induced diabetic mice. The cannabinoid receptor agonist WIN-55,212-2 (1mg/kg, i.p.), when injected into normal mice after conditioning, significantly prolonged the duration of freezing behavior. This effect was significantly inhibited by the cannabinoid CB1 receptor antagonist AM 251 (3mg/kg, s.c.), but not by the cannabinoid CB2 receptor antagonist AM 630 (1mg/kg, s.c.). The duration of freezing in STZ-induced diabetic mice was significantly longer than that in non-diabetic mice. The injection of WIN-55,212-2 (1mg/kg, i.p.) after conditioning significantly prolonged the duration of freezing in non-diabetic mice, but not in STZ-induced diabetic mice. In contrast, the injection of AM 251 (3mg/kg, s.c.) after conditioning significantly shortened the duration of freezing in STZ-induced diabetic mice, but not in non-diabetic mice. The injection of AM 251 (3mg/kg, s.c.) before conditioning or before testing did not significantly affect the duration of freezing in STZ-induced diabetic mice. The protein levels of cannabinoid CB1 receptors in the amygdala were increased in STZ-induced diabetic mice. In contrast, the protein levels of cannabinoid CB2 receptors and diacylglycerol lipase ?, the enzyme that synthesizes endocannabinoid 2-arachidonoylglycerol, in the amygdala did not differ between non-diabetic and STZ-induced diabetic mice. None of these proteins in the hippocampus was different between non-diabetic and STZ-induced diabetic mice. The injection of AM 251 (50 ng/side) into the basolateral amygdala significantly inhibited the duration of freezing in STZ-induced diabetic mice. Since endocannabinoid is controlled by glutamatergic function, we further examined the role of glutamatergic function in the increased fear memory in STZ-induced diabetic mice. The amounts of glutamine and glutamic acid in the amygdala of STZ-induced diabetic mice were significantly increased compared to those in non-diabetic mice. The AMPA receptor antagonist NBQX (4 0ng/side), when injected into the basolateral amygdala, significantly inhibited the duration of freezing in STZ-induced diabetic mice. Finally, AMPA (40 ng, i.c.v.) significantly prolonged the duration of freezing in normal mice, and this effect was inhibited by AM 251 (3mg/kg, s.c.). These results suggest that cannabinoid functions in the amygdala are increased in diabetic mice and that enhanced glutamatergic function in the amygdala of diabetic mice activates the endocannabinoid system, which enhances fear memory via cannabinoid CB1 receptors. PMID:25929688

  10. Hepatoprotective effects of selenium during diabetes in rats.

    PubMed

    Zou, C; Qiu, Q; Chen, H; Dou, L; Liang, J

    2016-02-01

    The present study investigated the hepatoprotective role of selenium during alloxan-induced diabetes in rats. Male Wistar rats were divided into four groups, namely, normal control, selenium treated, diabetic, and selenium-treated diabetic. Diabetes was induced in the animals by injecting alloxan intraperitoneally at a dose rate of 150 mg/kg body weight. Selenium in the form of sodium selenite was supplemented to rats at a dose level of 1 ppm in drinking water, ad libitum for two time durations of 2 and 4 weeks. The effects of different treatments were studied on various parameters in rat liver, which included serum glucose levels, serum insulin levels, alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), lipid peroxidation (LPO), glutathione reduced (GSH), oxidized glutathione (GSSG), total glutathione (TG), superoxide dismutase (SOD), catalase (CAT), glutathione reductase, glutathione peroxidase, metallothionein (MT), and histoarchitecture. A significant increase in the serum glucose levels, LPO levels, and in enzyme activities of ALP, ALT, and AST was observed in diabetic rats which, however, got decreased significantly upon supplementation with selenium. On the contrary, decreased enzyme activities of GSSG, SOD, and CAT and depressed levels of GSH as well as serum insulin levels were observed in diabetic rats which got improved following selenium supplementation. Interestingly, MT levels were increased both in diabetic and selenium-treated diabetic rats. Further, marked alterations in histoarchitecture were seen in diabetic rats with the prominent features being congestion in sinusoids, lipid accumulation, and centrilobular hepatocyte degeneration. However, selenium treatment to diabetic rats showed overall improvement in the hepatic histoarchitecture. PMID:25820154

  11. Characterization of Diabetic Neuropathy in the Zucker Diabetic Sprague-Dawley Rat: A New Animal Model for Type 2 Diabetes

    PubMed Central

    Davidson, Eric P.; Coppey, Lawrence J.; Holmes, Amey; Lupachyk, Sergey; Dake, Brian L.; Oltman, Christine L.; Peterson, Richard G.; Yorek, Mark A.

    2014-01-01

    Recently a new rat model for type 2 diabetes the Zucker diabetic Sprague-Dawley (ZDSD/Pco) was created. In this study we sought to characterize the development of diabetic neuropathy in ZDSD rats using age-matched Sprague-Dawley rats as a control. Rats were examined at 34 weeks of age 12