Diabetic Female Rats Research Articles

Effect of <i>Cissus quadrangularis</i> Linn on skeletal growth in the neonates of diabetic rats

Background: Infants of the diabetic mother are known to have reduced bone mineral content and hypocalcemia. Earlier, it has been shown that petroleum ether extract of Cissus quadrangularis (PECQ) can enhance the fetal skeletal ossification in normal rats. The present study was designed to evaluate the effect of ECQ on skeletal growth in the neonatal rats of streptozotocin-induced diabetic rats.Methods: After confirmation of diabetes, the diabetic and non-diabetic female Wistar rats were kept for mating with healthy male rats. After positive vaginal smear test, the pregnant rats were divided into three groups; the normal (non-diabetic) control (NC), diabetic control (DC), and diabetic+CQ (D+CQ) groups. The rats in the D+CQ group were given PECQ (500 mg/kg B.Wt), whereas animals in NC and DC groups were given 0.5% carboxy methyl cellulose, throughout the gestational period. Femur from the 1 week old neonatal rats from each group was collected randomly and subjected to histological analysis. Results: Thickness of trabecular bone and periosteum was significantly reduced in the neonates of DC rats compared with the neonates of NC group. Pretreatment with PECQ significantly improved the thickness of trabecular bone and periosteum compared with neonatal rats of DC group. No significant differences were observed in the medullary cavity width of femur between the groups. Conclusion: Data from the present study suggest that the PECQ can effectively attenuate the diabetes-induced reduction in the early skeletal growth. However, further research is warranted to evaluate the exact mechanism of action of phytochemical constituents of PECQ that can cross the placental barrier.

Combined effect of vitamins C and E on zinc status, carbohydrate metabolism and antioxidant values in diabetic rats fed zinc-deficient diet

The aim of this study was to investigate the combined effect of vitamin C and vitamin E on carbohydrate metabolism, zinc status and antioxidant enzymes activities in diabetic rats fed low zinc diet. Female diabetic albino Wistar rats were randomly assigned into five groups. The first group received a diet containing a 54 mg zinc/kg diet (adequate zinc, AZ), the second group received a diet containing 1 mg zinc/kg diet (zinc deficient group, ZD), and the three other groups received ZD diet and treated orally with vitamin E (500 mg/kg body wt) (ZD+VitE), vitamin C (500 mg/kg body wt) (ZD+VitC), and combined vitamins C and E (250 + 250 mg/kg body wt) (ZD+VitC+VitE) respectively. Body weight and food intake were recorded regularly. After four weeks of dietary manipulation. Serum and tissues zinc concentration, alkaline phosphatase activity of low-zinc diabetic animals were significantly lower than those of the control diabetic animals. Dietary zinc deficiency also increased significantly blood glucose, HbA1c, cholesterol and triglycerides concentrations, glutamate oxaloacetate transaminase, glutamate-pyruvate transaminase activities, and malondialdehyde level of low zinc diabetic rats. In contrast, catalase and glutathione peroxidase activities and liver glutathione level were reduced. Vit C or vit E may have partial ameliorative effects on these disturbances, whereas vit C and vit E together assured a more efficient protection. In conclusion vitamin E and C act as beneficial and potent antioxidants protect against lipid peroxidation and oxidative damage due to zinc deficiency associated with diabetes mellitus.

Cardiac mitochondria alteration and peripheral vessel morphology in female diabetes

One of diabetes complications is chronic cardiomyopathty and fibrotic alteration of aorta and peripheral vessels. Diabetes has been correlated to ROS superproduction (Lashin et al., 2006) and an alteration of mitochondrial chain complexes function in the whole heart (Herelin et al., 2011). Despite diabetic cardiomyopathy is most frequent in women, to date studies on female experimental diabetic models are lacking. Our aim was to investigate on heart mitochondrial oxygen phosphorylation (OXPHOS), and on aorta and portal vein morphology in female Wistar rats, after 4 and half months of streptozotocin-induced (65 mg/kg) diabetes. Mitochondrial OXPHOS was assessed by means of a Clark-type electrode on the following isolated mitochondrial subpopulations: left and right ventricles subsarcolemmal (SSM) and interfibrillar (IFM) mitochondria. Morphology and extracellular matrix composition of aorta and portal vein were investigated in light microscopy on paraformaldehyde fixed samples, stained with Masson Trichrome method (for collagen fibers) and Weigert’s stain (for elastic fibers). Evaluation of OXPHOS revealed an impairment of complex II in mitochondrial diabetic female rats in left and right IFM, but not in SSM. Interestingly, administration of the substrate glutamate resulted in an improvement of complex I efficiency in left IFM only, while association of complex I and II substrates displayed a reduced efficiency both in left and right IFM. Neither administration of glucidic substrates on SSM or of lipidic substrates on both SSM and IFM resulted in any change of mitochondrial OXPHOS efficiency. The study of connective fibrous composition in aorta and vena porta revealed a slight more abundant collagen production in the aorta’s wall and a disorganized and fragmented aspect of elastic bundles in the portal vein. Taken together, these data suggest a peculiar unknown development of diabetic cardiopathy in female rats.

Gender-dependent expression of pancreatic proteins in streptozotocin-induced diabetic rats

To elucidate gender-dependent protein regulation and molecular abnormalities in streptozotocin (STZ)-induced diabetes, we compared differentially expressed pancreatic proteins between male and female diabetic rats and their healthy controls using a 2-DE-based proteomic approach. In animal experiments, we found that females exposed to STZ displayed greater susceptibility towards diabetes development due to lower insulin secretion and severe β-cell damage. It was also accompanied with more impaired regulation of sex hormones, lower glucose tolerance, and higher blood glucose levels compared to male diabetic rats. Among 748 detected protein spots ranging in mass from 6 to 240 kDa between pH 3 and 10, a total of 42 proteins showed significant sexually-dimorphic regulation patterns between male and female diabetic rats. Proteomic data revealed that male and female rats displayed prominent gender-dimorphic differential regulation of pancreatic proteins involved in glycolysis, the citric acid cycle, amino acid synthesis, lipid metabolism, insulin biosynthesis, β-cell regeneration, cell signaling, as well as antioxidative and cellular stress defense. In conclusion, the current proteomic study revealed that severely impaired protein regulation in the pancreas, at least in part, is responsible for increased susceptibility of female rats to STZ-induced diabetes.

English

The aim of this study was to examine the progression of kidney damage induced by zinc deficiency in diabetic rats and to evaluate the effect of combined treatment of vitamin E and vitamin C in renal injury by providing protection against deleterious action of zinc deficiency. Female diabetic albino Wistar rats were randomly assigned into five groups. The first group received a diet containing a 54 mg zinc/kg diet (adequate zinc, AZ), the second group received a diet containing 1 mg zinc/kg diet (zinc deficient group, ZD), and the three other groups received ZD diet and treated orally with vitamin E (500 mg/kg body wt) (ZD + Vit E), vitamin C (500 mg/kg body wt) (ZD + Vit C), and combined vitamins C and E (250 + 250 mg/kg body wt) (ZD+VitC+VitE), respectively. Body weight was recorded regularly (twice weekly). After four weeks of dietary manipulation, kidney zinc level, serum albumin and total protein concentration of ZD group were significantly lower than those of AZ group. Dietary zinc deficiency also increased proteinuria excretion, serum and urinary urea and uric acid levels, serum creatinine and kidney malondialdehyde concentration. In contrast, the catalase activity and reduced glutathione level in the kidney were reduced. In conclusion, vitamins E and C act as beneficial antioxidants protect renal function against the noticed oxidative stress due to zinc deficiency and experimental diabetes. Keywords: Experimental diabetes, zinc, vitamin E, vitamin C, oxidative stress, kidney damage.

Abstract 501: Enhanced Expression of the Endocannabinoid 2-AG and CB-1 Receptor in the Kidney of the Diabetic Hypertensive Female Rat

The cannabinoids arachidonoylethanolamide (AEA) and 2-arachidonoylglycerol (2-AG) are endogenous ligands for the cannabinoid receptors including CB1 and CB2 subtypes. The endocannabinoid system (ECS) is typically associated with regulation of metabolic balance and appetite, although CB1 receptors (CB1R) may contribute to diabetic renal injury while CB2R are protective. The hypertensive mRen2.Lewis (mRen2) females have less renal injury than the males; however, diabetic female mRen2 lack this protection and show comparable indices of injury to the diabetic males. The present study addressed whether female and male diabetic mRen2 exhibit similar alterations in the renal ECS. Diabetes was induced with a single dose of streptozotocin (STZ at 65 mg/kg; ip). Cortical content of AEA and 2-AG was quantified by UPLC MS/MS. Receptor levels and the metabolizing enzymes for AEA (FAAH) and 2-AG (MAGL) were quantified by protein immunoblot. Basal 2-AG content was higher in male versus female mRen2, and significantly increased in both diabetic females and males (figure, n=6) while AEA was unchanged. Cortical Ang II correlated to 2-AG [p<0.01; r = 0.89]. CB1R protein expression was higher in female diabetic mRen2 but unchanged in the males (figure, n=4). CB2R expression was lower in the male diabetics [p<0.01; n=4], but not changed in females. MAGL expression was >70% lower in female diabetics compared to controls [p<0.05; n=4] while FAAH was not changed. Elements of the renal ECS are differentially regulated in the diabetic mRen2. Higher expression of both 2-AG and CB1R, but reduced MAGL (females) and CB2R (males) may contribute to the development and progression of renal injury in this model.

Abstract 507: Combined Exercise Training Induces Additional Cardiovascular Autonomic Benefits in Comparison to Dynamic Resistance Training in Ovariectomized Diabetic Rats

The purpose of this study was to compare the cardiovascular autonomic effects between dynamic aerobic, resistance and combined exercise training in ovariectomized diabetic female rats. Female Wistar rats (200-220g) were divided into 4 ovariectomized (bilateral ovaries removal) diabetic (streptozotocin, 50mg/kg, iv) groups: sedentary (DOS) and trained by an aerobic protocol on a treadmill (DOTA), by a resistance protocol in ladder (DOTR), or by a combined protocol in ladder+treadmill on alternate days (DOTC). After 8 weeks of training, the animals were cannulated to arterial pressure (AP) recording and baroreflex sensitivity (BS) evaluation. Heart rate (HR) and systolic AP variabilities were analyzed in the time and frequency domains. Exercise training induced an increase of 77% in the run capacity in the DOTA group (DOS: 8.6±0.6; DOTA: 15.3±0.4; DOTR: 11.5±1.6; DOTC: 15.0±0.2 min), 60% in the maximum load in DOTR group (DOS: 179.7±11.0; DOTA: 167.3±1.5; DOTR: 288.4±7.5; DOTC: 284.6±10.2 % of body weight), and increases in both exercise tests in DOTC (75% and 58%, respectively). All trained animals showed normalization of diabetic induced-resting hypotension and bradycardia, associated with increased HR variance (DOS: 39.6±2.6; DOTA: 71.2±7.2; DOTR: 70.9±12.1; DOTC: 65.7±6.1 ms2) and normalization of the LF band of pulse interval (DOS: 2.7±0.3; DOTA: 5.3±0.4; DOTR: 7.2±1.5; DOTC: 6.8±0.8 ms2) (vs. DOS). The DOTA and DOTC groups (but not DOTR) had higher BS (tachycardic and bradycardic responses), and attenuation in SAP variability (DOS: 7.4±0.8; DOTA: 12.7±1.1; DOTR: 8.9±1.0; DOTC: 13.3±1.0 mmHg2) in relation to DOS. Mortality was higher in DOS group when compared to trained group. In conclusion, the results showed that dynamic aerobic, resistance or combined exercise training induced benefits in physical capacity, hemodynamic and autonomic parameters after ovarian hormone deprivation in diabetic rats. However, the combined exercise training promoted additional effects than aerobic or resistance training in this condition.

Anti-diabetic, anti-hyperlipidaemic and anti-oxidant effects of total saponin fractions of Irvingia gabonensis stem bark on streptozotocin diabetic female rats

Anti-diabetic, anti-hyperlipidaemic and anti-oxidant effects of total saponin fractions of Irvingia gabonensis stem bark on streptozotocin diabetic female rats

The histopathological and biochemical effects of enalapril and pyridoxamine on the kidney of streptozotocin diabetic female rats

Objective The aim of this study was to evaluate the histopathological and biochemical effects of enalapril (an angiotensin-converting enzyme inhibitor) and pyridoxamine (an advanced glycation end product inhibitor) on the kidneys of streptozotocin diabetic female rats. Materials and methods Eighty adult female rats weighing 150–200 g were used for the study and divided into four groups: group I (control nondiabetic group), group II (diabetic untreated group), group III (diabetic group treated with enalapril), and group IV (diabetic group treated with pyridoxamine), with each group comprising 20 rats (n=20). Diabetes was induced by a single intraperitoneal injection of streptozotocin (55 mg/kg). Enalapril was administered (50 mg/l) in the drinking water and pyridoxamine was administered (1 g/l) in the drinking water for 28 weeks. Biochemical estimation of fasting blood glucose, serum creatinine, and plasma tumor necrosis factor-α (TNF-α) was performed. The kidneys of the rats were collected for examination of clinical biochemistry, which included measurement of levels of tissue malondialdehyde (MDA), enzymatic antioxidants such as superoxide dismutase (SOD) and catalase (CAT), and nonenzymatic antioxidants such as reduced glutathione (GSH), and were studied histopathologically by light microscopy and immunohistochemistry. Results Fasting blood glucose was significantly increased, whereas the levels of serum creatinine and plasma TNF-α were highly significantly increased in the diabetic untreated group but the levels of serum creatinine and plasma TNF-α were significantly reduced in the diabetic group treated with enalapril and pyridoxamine. The level of MDA was significantly increased, whereas the levels of SOD, CAT, and GSH were significantly decreased in the kidneys of the diabetic untreated group; however, the level of MDA was decreased, whereas levels of SOD, CAT, and GSH were increased in the diabetic group treated with enalapril and pyridoxamine. Kidney histopathology of streptozotocin in diabetic rats showed pathological changes. However, treatment with enalapril and pyridoxamine attenuated the histopathological changes and corrected the biochemical parameters mentioned above. Conclusion Diabetic nephropathy is one of the most frequent and serious complications of diabetes mellitus. Enalapril and pyridoxamine have renoprotective effects, which have been shown to inhibit structural and functional aspects of diabetic nephropathy and attenuate oxidative stress involved in the streptozotocin diabetic kidney.

Gender dimorphism in regulation of plasma proteins in streptozotocin-induced diabetic rats

In the present study, we examined differentially regulated plasma proteins between healthy control and streptozotocin (STZ)-induced male and female diabetic rats by 2DE-based proteomic analysis. Animal experiments revealed that significantly lower plasma insulin levels were observed in female diabetic rats, consequently resulting in higher blood glucose levels in female diabetic rats. Importantly, plasma levels of sex hormones were significantly altered in a gender-dependent manner before and after STZ treatment. Results of the animal experiment indicated the existence of sexual dimorphism in the regulation of plasma proteins between healthy control and diabetic rats. Plasma proteome analysis enabled us to identify a total of 38 proteins showing sexual dimorphic regulation patterns. In addition, for the first time, we identified several differentially regulated plasma proteins between healthy control and diabetic rats, including apolipoprotein E, fetuin B, α-1-acid glycoprotein, β-2-glycoprotein 1, 3-hydroxyanthranilate 3,4-dioxygenase, and serum amyloid P-component. To the best of our knowledge, this is the first proteomic approach to address sexual dimorphism in diabetic animals. These proteomic data on gender-dimorphic regulation of plasma proteins provide valuable information that can be used for evidence-based gender-specific clinical treatment of diabetes.

Growth hormone exacerbates diabetic renal damage in male but not female rats.

BackgroundHuman and animal studies support the idea that there are sex differences in the development of diabetic renal disease. Our lab and others have determined that in addition to Ang II (through the AT1R), growth hormone (GH) contributes to renal damage in models of renal failure; however, the impact of sex and GH on the mechanisms initiating diabetic renal disease is not known. This study examined the effect of sex and GH on parameters of renal damage in early, uncontrolled streptozotocin (STZ)-induced diabetes.MethodsAdult male and female Sprague–Dawley rats were injected with vehicle (control), STZ, or STZ + GH and euthanized after 8 weeks.ResultsMild but significant glomerulosclerosis (GS) and tubulointerstitial fibrosis (TIF) was observed in both kidneys from male and female diabetic rats, with GH significantly increasing GS and TIF by 30% and 25% in male rats, but not in female rats. STZ increased TGF-β expression in both kidneys from male and female rats; however, while GH had no further effect on TGF-β protein in diabetic females, GH increased TGF-β protein in the male rat’s kidneys by an additional 30%. This sex-specific increase in renal injury following GH treatment was marked by increased MCP-1 and CD-68+ cell density. STZ also reduced renal MMP-2 and MMP-9 protein expression in both kidneys from male and female rats, but additional decreases were only observed in GH-treated diabetic male rats. The sex differences were independent of AT1R activity.ConclusionsThese studies indicate that GH affects renal injury in diabetes in a sex-specific manner and is associated with an increase in pro-inflammatory mediators.

Role of nitric oxide and endothelin in endothelial maintenance of vasoconstrictor responses in aortas of diabetic female rats (一氧化氮与内皮素对糖尿病雌性大鼠主动脉血管内皮维持血管收缩反应的影响)

Diabetes differentially affects the vascular system in males and females. Although various results have been reported, very few studies have focused on responses in females. In the present study, we investigated contractile responses to norepinephrine in aortas of alloxan-diabetic female rats and evaluated endothelial modulation of these responses. Concentration-response curves were constructed to norepinephrine in the absence or presence of N(G) -nitro-l-arginine methyl ester (l-NAME), indomethacin, losartan, tezosentan, and calphostin C; pre-pro-endothelin mRNA expression was evaluated; and norepinephrine-stimulated expression of phosphorylated (p-) Akt Ser(473) , p-endothelial nitric oxide synthase (eNOS) Ser(1177) , and p-eNOS Ser(633) was determined in endothelial cells incubated in the presence of low (5 mmol/L) or high (25 mmol/L) glucose concentrations. Similar maximal responses (Rmax ) to norepinephrine were seen in control and diabetic endothelium-intact aortas; however, Rmax was reduced in diabetic endothelium-denuded aortas. Incubation of endothelium-intact aortas with 100 μmol/L l-NAME increased Rmax in the control group only. Inhibition of cyclo-oxygenase (10 μmol/L indomethacin) and blockade of angiotensin II receptors (10 μmol/L losartan) reduced Rmax in endothelium-intact aortas in both the control and diabetic groups. Blockade of endothelin receptors (0.1 μmol/L tezosentan) and inhibition of protein kinase C (PKC; 0.1 μmol/L calphostin C) reduced Rmax only in endothelium-intact aortas from diabetic rats. Pre-pro-endothelin mRNA expression was increased in aortas from diabetic female rats. Finally, p-Akt Ser(473) , p-eNOS Ser(1177) , and p-eNOS Ser(633) levels were enhanced after norepinephrine stimulation only in low glucose-treated endothelial cells. In aortas of diabetic female rats, reductions in smooth muscle contractile responses to norepinephrine are counterbalanced by the endothelium via reduced eNOS activation and increased endothelin release and PKC activation.

Sex Differences in Aortic Endothelial Function of Streptozotocin‐induced Diabetic Rats: A Possible Role of Superoxide Production

Little is known of the interaction between diabetes and gender in the vasculature. This study was designed to investigate 1) whether there were gender differences in rat aortic endothelium‐dependent vasodilation (EDV) in streptozotocin (STZ, 60 mg/kg, iv)‐induced diabetic rats at early stage of the disease (1 wk), and 2) the potential role of superoxide in diabetes‐induced vascular dysfunction. EDV to acetylcholine (ACh; 10−8 to 10−5 M) was measured in aortic rings precontracted with phenylephrine (2 μM) before and after pretreatment with MnTMPyP (10 mM), a superoxide scavenger. In addition, the level of endothelial nitric oxide synthase (eNOS) and NADPH oxidase (Nox, a potent sources of superoxide) 1, 2 and 4 mRNA expression were determined using real‐time RT‐PCR. ACh‐induced relaxations were significantly impaired in aortic rings from both male and female diabetic rats. However, the extent of impairment was significantly greater in diabetic females than diabetic males. Preincubation with MnTMPyP increased EDV only in diabetic female group. Accordingly, our data showed that in females, the level of Nox4 mRNA expression was substantially enhanced, whereas the level of eNOS mRNA expression was decreased at 1 wk after the induction of diabetes. These data suggest that the predisposition of female rat aorta to vascular injury in diabetes is possibly due to the superoxide production (supported by NIH/NIDCR).

Hypoglycemic Effect of Hazelnut and its Effect on Some Sex Hormones in Alloxan Induced Diabetic in Female Rats

2 Abstract: Hazelnut is the second richest source of monounsaturated fatty acids among nuts and is rich in vitamins E a nd B6, phytosterols, folate, L-arginine, polyphenols and fiber. The present study aimed to investigate the hypoglycemic effect of hazelnut and its effect on some sex hormones in diabetic female rats. Animals were randomly assigned to five groups of equal number and weight. Group I, kept as a normal control group; Group II, kept as a diabetic control group, Groups III, IV and V, kept as diabetic groups and feeding supplemented diet with 5, 10 and 15% hazelnuts, respectively. Supplemented diet with 10% and 15% of hazelnut significantly lower food intake compare to the positive control group. Body weight gain significantly increased in treated diabetic group compare with the positive control group. Feeding supplemented diet with hazelnut at the three different levels caused significantly lower in concentrations of blood glucose, total lipids, triglycerides, total cholesterol, AST, ALT, blood urea nitrogen, uric acid and creatinine and significantly lower in levels of insulin, thyroid stimulating, follicle-stimulating and luteinizing hormones compared to that of untreated diabetic rats. Histological study showed hypertrophy and hyperplasia in beta-cells of islets of langerhans associated with pyknosis of their nuclei in positive control rats. Slight hypertrophy in islets of langerhans and congestion of pancreatic blood vessel was showed in pancreas sections of treated rats with 5 and 10% of hazelnut, respectively. However, rats treated with 15% of hazelnut showed apparent normal histological structure. Ovary sections of positive control rats showed dilation and congestion of blood vessel as well as interstitial connective tissue proliferation. Interstitial cells hyperplasia and follicles were showed in ovary of treated rats with 5 and 10% of hazelnut, respectively. Primary oocytes were showed in ovary sections of treated rats with 15% of hazelnut. In conclusions, hazelnut can be readily incorporated into healthy diet to its healthy effect benefits in diabetes and its complication.

The histopathological and biochemical effects of green tea extract on the liver of high-fat diet and streptozotocin diabetic female rats

The histopathological and biochemical effects of green tea extract on the liver of high-fat diet and streptozotocin diabetic female rats

Effects of fresh, aged and cooked garlic extracts on short- and long-term memory in diabetic rats.

The present study was hypothesized to investigate the beneficial effects of fresh, aged, and cooked garlic extracts on blood glucose and memory of diabetic rats induced by streptozocine (STZ). Diabetes was induced by an intraperitoneal injection of STZ (60 mg/kg body weight). An oral dose of 1000 mg/kg of each garlic extract was given daily for 4 weeks after diabetes induction. Five days after STZ injection, five groups were formed: Control (intact) rats (Cont) + Vehicle of garlic extract (normal saline) (Veh), STZ + Veh, STZ + Fresh (row) garlic (FG), STZ + Aged garlic (AG), and STZ + cooked (boiled) garlic (CG). In order to assess the passive avoidance memory, rats were gently placed on the wooden platform, and latency to step-down (SDL) was recorded as initial phase, after then a light electrical shock [0.3 mA, 3 sec, Alternative current (AC)] was delivered to their foot paw. The retrieval tests were done for short- and long-term memories, respectively. Blood glucose was assayed by glucometer before and after treatment with STZ and garlic extracts. Hyperglycemia induced by STZ decreased short-term memory in both diabetic males and females rats significantly compared with the controls (p<0.001 and p<0.01). Fresh and cooked but not aged garlic extracts decreased blood glucose in diabetic males and increased memory in both diabetic male and female rats significantly (p<0.05 and p<0.01). STZ causes elevation of the blood glucose and resulted in memory deficits, possibly viafree radicals production in brain tissue. Garlic has some bioactive chemicals including allicin and sulfur compound (OSC) which could lower the blood glucose during chronic hyperglycemia, inhibit free radicals production in brain, and improve short-term (but not long-term) memory.

Effect of diets with different fat contents on the development of diabetes in female Zucker diabetic fatty rat with leptin mutation

The aim of the study was to develop a diet which causes stable hyperglycaemia and development of diabetes in female Zucker diabetic fatty (ZDF) rats. We also examined whether worsened wound healing is caused only by hyperglycaemia or whether it is caused by more factors. Four types of special diets with a different content of fat were fed to eight groups of 3–7 (fa/fa or fa/+) rats. The following diets were used: H1 (24.6% fat), H2 (33.2%), C13004 (25.6%), and St1 (3.4%). We detected significant diet-dependent changes of weight and concentration of glucose in animals with leptin mutation (fa/fa). All examined indicators were significantly (P &lt; 0.001) higher in (fa/fa) animals compared to the fa/+ ones no matter what diet they ate. All diets with high-fat content caused increased glycaemia, but only the diet with 24.6% fat caused a significant (P &lt; 0.01) increase of glycaemia. Our results have proved that this diet is the most suitable to invoke and keep hyperglycaemia. The diet with 25.6% fat is suitable to invoke stable slightly increased glycaemia (10 mmol/l) and hyperinsulinaemia. On the other hand, the diet with 33.2% fat is unsuitable. We did not observe a significant influence of diet on wound healing. We developed a new diet more suitable for induction of stable hyperglycaemia in female ZDF rats than commercially available mixtures. Our study is the first to present recommendations for adjusting a high-fat diet to produce stable hyperglycaemia and hyperinsulinaemia in the rat model.

Evaluation of the Effects of STZ-Induced Diabetes onIn VitroFertilization and Early Embryogenesis Processes

The aim of this study was to investigate the effects of experimentally induced diabetes on (a) germ cells, (b) in vitro fertilization (IVF) success rate, and (c) gap junction and cell adhesion molecule gene and protein expressions during the early blastocyst period. Germ cells were obtained from healthy and diabetic rats, analyzed for number, motility, and morphology, and used for IVF. After reaching the early blastocyst stage, the expressions of genes encoding gap junction proteins and cell adhesion molecules were analyzed by quantitative RT-PCR. Histomorphologically and immunohistochemically analyses were also performed. Diabetes significantly affected sperm number and motility and the development of oocytes. Gene expressions of β-catenin and connexin family members and protein expressions of E-cadherin and connexin-43 significantly decreased in groups including germ cells isolated from diabetic rats. Connective tissue growth factor expression increased in groups that included sperm cells isolated from diabetic male rats, whereas mucin-1 expression increased in the group that included oocytes isolated from diabetic female rats paired with sperm cells isolated from healthy male rats. In summary, experimentally induced diabetes was found to influence gap junctions, cell adhesion molecules, and associated proteins which all have important roles in germ cell maturation, fertilization, and development.

Gender-Dimorphic Regulation of Skeletal Muscle Proteins in Streptozotocin-Induced Diabetic Rats

Background: Despite the fact that sexual differences increase diabetic risk and contribute to the need for gender-specific care, there remain contradictory results as to whether or not sexual dimorphism increases susceptibility to the development of type 1 diabetes mellitus. Methods: To examine gender-dimorphic regulation of skeletal muscle proteins between healthy control and STZ-induced diabetic rats of both genders, we performed differential proteome analysis using two-dimensional electrophoresis combined with mass spectrometry. Results: Animal experiments revealed that STZ treatment rendered female rats more susceptible to induction of diabetes than their male littermates with significantly lower plasma insulin levels due to hormonal regulation. Proteomic analysis of skeletal muscle identified a total of 21 proteins showing gender-dimorphic differential expression patterns between healthy controls and diabetic rats. Most interestingly, gender-specific proteome comparison showed that male and female rats displayed differential regulation of proteins involved in muscle contraction, carbohydrate, and lipid metabolism, as well as oxidative phosphorylation and cellular stress. Conclusion: The current proteomic study revealed that impaired protein regulation was more prominent in the muscle tissue of female diabetic rats, which were more susceptible to STZ-induced diabetes. We expect that the present proteomic data can provide valuable information for evidence-based gender-specific treatment of diabetes.

Sex differences in pain-related behavior and expression of calcium/calmodulin-dependent protein kinase II in dorsal root ganglia of rats with diabetes type 1 and type 2

Sex differences in pain-related behavior and expression of calcium/calmodulin dependent protein kinase II (CaMKII) in dorsal root ganglia were studied in rat models of Diabetes mellitus type 1 (DM1) and type 2 (DM2). DM1 was induced with 55mg/kg streptozotocin, and DM2 with a combination of high-fat diet and 35mg/kg of streptozotocin. Pain-related behavior was analyzed using thermal and mechanical stimuli. The expression of CaMKII was analyzed with immunofluorescence. Sexual dimorphism in glycemia, and expression of CaMKII was observed in the rat model of DM1, but not in DM2 animals. Increased expression of total CaMKII (tCaMKII) in small-diameter dorsal root ganglia neurons, which are associated with nociception, was found only in male DM1 rats. None of the animals showed increased expression of the phosphorylated alpha CaMKII isoform in small-diameter neurons. The expression of gamma and delta isoforms of CaMKII remained unchanged in all analyzed animal groups. Different patterns of glycemia and tCaMKII expression in male and female model of DM1 were not associated with sexual dimorphism in pain-related behavior. The present findings do not suggest sex-related differences in diabetic painful peripheral neuropathy in male and female diabetic rats.