Effects of vanadyl sulfate on kidney in experimental diabetes

The aim of this work was to investigate the biochemical and histological effects of vanadyl sulfate on blood glucose, urea, and creatinine in serum and nonenzymatic glycosylation and glutathione levels in kidney tissue of normal and streptozotocin (65 mg/kg) diabetic rats. Vanadyl sulfate was administered by gavage at a dose of 100 mg/kg. After 60 d of treatment, serum urea, creatinine, and blood glucose levels significantly increased in the diabetic group but not so in the vanadyl sulfate, which showed significantly reduced serum urea and blood glucose levels and a nonsignificant reduction of serum creatinine levels. Nonenzymatic glycosylation was increased and the glutathione level was decreased in the kidney tissue of diabetic rats. Treatment with vanadyl sulfate reversed these effects. Degenerative changes were detected in diabetic animals by electron and light microscopy. Although there are individual differences in diabetic animals given vanadium, some reduction of degenerative changes were observed.     

Assessment of chronic administration of aloe vera gel on haematology, plasma biochemistry, lipid profiles and erythrocyte osmotic resistance in wistar rats

The study was designed to investigate the effects of chronic administration of Aloe vera gel extract on markers of hepatic damage, lipid profiles and erythrocyte osmotic fragility using the Wistar rats. Forty male Wistar rats divided into four groups of ten rats per group were used in the study. Group I which served as the control received 0.9% physiological saline while those in groups II, III and IV received Aloe vera gel (100, 250 and 500mg/kg), respectively, for four weeks. There was significant increase in the haemoglobin concentration while the PCV, RBC count, MCH and MCHC though showed some marginal increases but the increases were not significant in all the treated rats. No significant change was also observed in the erythrocyte osmotic fragility. However, there were significant reductions in plasma ALT, AST and ALP levels in animals that received the gel compared with the control while the plasma albumin and total protein values were higher than those of the control. All the animals that received the gel also showed significant reduction in plasma total cholesterol, triglycerides and LDL-cholesterol ratio compared with the control. In a similar manner, those animals that were administered with 500mg/kg gel had significantly higher HDL-cholesterol ratio than those of the control. This study showed that, chronic administration of Aloe vera gel extract had no significant effects on the haematological parameters of the rats and did not affect erythrocyte osmotic resistance. It however showed some cholesterol lowering action.keywords: Aloe vera, Haematology, Osmotic fragility, Plasma biochemistry.     

Alterations in kidney tissue following zinc supplementation to STZ-induced diabetic rats

Diabetes mellitus is a chronic disease characterized by anomalies forming in carbohydrate, lipid, protein metabolisms and the incidence of this disease varies widely throughout the world. Zinc is an important element which is essential for life and is present in nature. In this study, the animals were divided into four groups. These groups were named as untreated; zinc sulfate; streptozotocin (STZ); STZ and zinc sulfate. STZ (65 mg/kg) was dissolved in a freshly prepared 0.01 M pH 4.5 citrate buffer and given with intraperitoneal injection in a single dose. Zinc sulfate (100 mg/kg) was dissolved in distilled water and given to the animals by gavage at a daily dose for 60 days. The rats were sacrificed under ether anesthesia. This study was aimed to investigate histological and biochemical changes of zinc supplementation on the kidney tissue in STZ-induced diabetic rats. In the current study, histological and histochemical observations showed that the occurred degenerative changes decreased after giving zinc in the kidney tissue of diabetic group. Kidney glutathione (GSH) levels decreased and lipid peroxidation (LPO), nonenzymatic glycosylation (NEG), urea and creatinine levels increased in diabetic rats. GSH levels increased, while LPO, NEG, urea and creatinine levels decreased in the kidney with administration of zinc to diabetic rats. As a result, we observed curative effects of zinc given to diabetic rats. We can say that zinc may be an important antioxidant for the treatment of secondary complications of diabetes in kidney tissue.     

Chemomodulatory action of Aloe vera on the profiles of enzymes associated with carcinogen metabolism and antioxidant status regulation in mice.

The effect of two doses (30 microl and 60 microl/day/mice daily for 14 days) of the fresh leaf pulp extract of Aloe vera was examined on carcinogen-metabolizing phase-I and phase-II enzymes, antioxidant enzymes, glutathione content, lactate dehydrogenase and lipid peroxidation in the liver of mice. The modulatory effect of the pulp extract was also examined on extrahepatic organs (lung, kidney and forestomach) for the activities of glutathione S-transferase, DT-diophorase, superoxide dismutase and catalase. The positive control mice were treated with butylated hydroxyanisole (BHA). Significant increases in the levels of acid soluble sulfhydryl (-SH) content, NADPH-cytochrome P450 reductase, NADH-cytochrome b5 reductase, glutathione S-transferase (GST), DT-diaphorase (DTD), superoxide dismutase (SOD), catalase, glutathione peroxidase (GPX) and glutathione reductase (GR) were observed in the liver. Aloe vera significantly reduced the levels of cytochrome P450 and cytochrome b5. Thus, Aloe vera is clearly an inducer of phase-II enzyme system. Treatment with both doses of Aloe caused a decrease in malondialdehyde (MDA) formation and the activity of lactate dehydrogenase in the liver, suggesting its role in protection against prooxidant-induced membrane and cellular damage. The microsomal and cytosolic protein was significantly enhanced by Aloe vera, indicating the possibility of its involvement in the induction of protein synthesis. BHA, an antioxidant compound, provided the authenticity of our assay protocol and response of animals against modulator. The pulp extract was effective in inducing GST, DTD, SOD and catalase as measured in extrahepatic organs. Thus, besides liver, other organs (lung, kidney and forestomach) were also influenced favorably by Aloe vera in order to detoxify reactive metabolites, including chemical carcinogens and drugs.     

Phytotherapeutic efficacy of the medicinal plant Terminalia catappa L.

Diabetes is a chronic, lifelong condition due to inadequate production of insulin or the cells does not properly respond it. Recently, the significance and effectiveness of herbal drugs associated with diabetes has emerged. The aim of the present study was to determine the anti-diabetic effects of Terminalia catappa L. leaves on streptozotocin (STZ)-treated rats. Two different concentrations of ethanolic leaf extract (300 and 500 mg/kg) of T. catappa were used to treat diabetic rats, and biochemical parameters were analyzed in blood samples. The results of herbal treatments were compared with the standard drug, glibenclamide. The ethanol extract (500 mg/kg) had significant anti-diabetic activity by altering blood glucose, glycosylated hemoglobin, liver glycogen, glucose 6-phosphatase, fructose 1,6-bisphosphatase, glucokinase, aspartate transaminase, alanine transaminase, alkaline phosphatase, urea, uric acid and creatinine levels while increasing insulin levels. Thus, the present study suggests that the supplementation of the diabetic patients with T. catappa leaves can lead to recovery from diabetic effects.     

阿魏酸对糖尿病大鼠肾脏足细胞nephrin、podocin蛋白表达的影响

目的：研究阿魏酸（FA）对链脲佐菌素（STZ）致糖尿病大鼠肾脏足细胞损伤的影响,并探讨其可能的机制。方法：雄性SD大鼠尾静脉一次性注射STZ （40 mg/kg,i.v.）,72 h后将血糖高于16.7 mmol/L者视为糖尿病造模成功,将其随机分为模型组、阿魏酸组,每组10只;另取10只雄性SD大鼠作为对照组;阿魏酸组（100 mg/kg,i.g.,qd）,从大鼠血糖升高第5周开始给药,连续8周。测定空腹血糖、体重、肾脏脏器系数、血清尿素氮、肌酐含量;HE染色观察肾组织病理变化;免疫组化测定肾组织nephrin、podocin蛋白表达。结果：与对照组比较,模型组肾脏脏器系数增大,肾功能下降;病理学显示肾脏细胞萎缩,排列不整齐,并伴有间质增生;足细胞nephrin、podocin蛋白表达明显减少,阿魏酸组明显改善上述指标。结论：阿魏酸具有改善STZ致糖尿病大鼠肾脏功能的作用,其机制可能与上调肾脏足细胞nephrin、podocin蛋白表达有关。     

乙醇激动ALDH2对糖尿病大鼠肾脏JNK表达的影响

目的：观察乙醇激动乙醛脱氢酶2（ALDH2）对糖尿病大鼠肾脏c-Jun氨基末端激酶（JNK）表达的影响。方法：18只健康雄性SD大鼠随机分为正常对照组、糖尿病组、乙醇＋糖尿病组（n=6）。造模8周后,测定血糖、糖化血红蛋白、肾功能、24h尿蛋白含量等指标,测定肾重指数,观察肾脏病理结构改变,检测肾脏组织ALDH2、p-JNK及JNK蛋白表达。结果：与正常对照组相比,糖尿病组血糖、糖化血红蛋白、尿素氮、肌酐、24h尿蛋白量及肾重指数均明显升高。病理切片显示：肾小球系膜基质增多、基底膜增厚、毛细血管腔变窄。肾脏组织ALDH2蛋白表达下降,p-JNK、JNK蛋白表达增加,p-JNK／JNK显著增高。给予乙醇干预后,肾功能损伤降低,病理改变减轻,肾脏组织ALDH2增高,p-JNK、JNK表达下降,p-JNK／JNK降低。结论：增加ALDH2表达可能通过抑制JNK信号通路的活性减轻糖尿病大鼠肾脏损伤。     

Asparagus racemosus Willd (Liliaceae) ameliorates early diabetic nephropathy in STZ induced diabetic rats

Diabetic nephropathy is a major "microvascular" complication of diabetes, differs from other causes of chronic kidney diseases in its predictability, with well-defined functional progression from hyperfiltration to micro- to macroalbuminuria to renal failure. The present study was undertaken to investigate the effect of Asparagus racemosus Willd (Liliaceae) on streptozotocin-induced early diabetic nephropathy. Single i.p injection of streptozotocin (55 mg/kg) was administered to induce early diabetic nephropathy in Wistar rats and thereafter treated orally with ethanolic extract of Asparagus racemosus (EEAR) at a dose level of 100 and 250 mg/kg daily for 4 weeks. The efficacy of extract was compared with diabetic control rats. A. racemosus treatment significantly decreased plasma glucose, creatinine, urea nitrogen, total cholesterol and triglyceride levels. Renal hypertrophy, polyuria, hyperfiltration, microalbuminuria and abnormal changes in the renal tissue as well as oxidative stress were effectively attenuated by EEAR treatment. Basement membrane thickening and mesangial proliferation formation without nodules were seen in diabetic rats, whereas these structural changes were reduced in EEAR treated groups. Results of this study suggested that A. racemosus has beneficial effect in the treatment of diabetic     

Therapeutic effect of Acacia nilotica pods extract on streptozotocin induced diabetic nephropathy in rat

The aim of the present study was to examine the effect of aqueous methanol extract (150 and 300mg/kg body weight) of Acacia nilotica pods in streptozotocin-induced diabetic rats for 60days, and its biochemical, histopathological and histochemical study in the kidney tissues. Diabetic rats exhibited hyperglycemia, elevated of serum urea and creatinine. Significant increase in lipid peroxidation (LPO), superoxide dismutase (SOD) and reduced glutathione (GSH) was observed in diabetic kidney. Histopathological examination revealed infiltration of the lymphocytes in the interstitial spaces, glomerular hypertrophy, basement membrane thickening and tubular necrosis with loss of their brush border in some of the proximal convoluted tubules in diabetic rats. Acacia nilotica extract lowered blood glucose levels, restored serum urea and creatinine. In addition, Acacia nilotica extract attenuated the adverse effect of diabetes on LPO, SOD and GSH activity. Treatment with Acacia nilotica was found to almost restore the normal histopathological architecture of kidney of streptozotocin-induced diabetic rats. However, glomerular size and damaged area showed ameliorative effect after treatment with the extract. In conclusion, the antioxidant and antihyperglycemic properties of Acacia nilotica extract may offer a potential therapeutic source for the treatment of diabetes.     

Dietary vitamin C and E modulates oxidative stress induced-kidney and lens injury in diabetic aged male rats through modulating glucose homeostasis and antioxidant systems

Diabetes induces oxidative stress in aged human and rat, although daily supplementation of vitamins C and E (VCE) can be beneficial to aged diabetic rats by reducing free radical production. The aim of the present study was to evaluate whether dietary VCE supplementation relieves oxidative stress in streptozotocin (STZ)-induced diabetic in aged rats. Thirty aged rats were randomly divided into three groups. The first group was used as a control. The second group was made diabetic using a single dose of intraperitoneal STZ. VCE-supplemented feed was given to aged diabetic rats constituting the third group. On the 21st day of the experiment, blood, lens and kidney samples were taken from all animals. Glutathione peroxidase (GSH-Px) activity in lens and kidney, reduced glutathione (GSH), vitamin E and β-carotene concentrations in kidney were lower in the diabetic group than in the control whereas plasma glucose, urea and creatinine, and kidney and lens peroxidation (LP) levels were higher in the diabetic group than in the control. However, kidney and lens LP levels, and plasma glucose, urea and creatinine values were decreased by VCE supplementation. Lens and kidney GSH-Px activity, kidney GSH, vitamin E and β-carotene concentrations and erythrocyte counts were increased by VCE treatment. Kidney weights, vitamin A, haemoglobin, hematocrit, leukocyte and platelets values were not changed by diabetes and/or VCE supplementation. VCE ameliorated also diabetes-induced histopathological changes in kidney. In conclusion, we observed that VCE supplementation is beneficial towards kidney and lens of aged diabetic rats by modulating oxidative and antioxidant systems.     

Ginkgo biloba extract ameliorates gentamicin-induced nephrotoxicity in rats.

The effect of Ginkgo biloba (EGb), a plant extract with an antioxidant effect, has been studied on gentamicin-induced nephrotoxicity in male wistar rats. Ginkgo biloba extract (300 mg/kg BW) was administered orally 2 days before and 8 days concurrently with gentamicin (80 mg/kg BW). Saline treated animals served as control. Estimations of urine creatinine, glucose, blood urea, serum creatinine, plasma and kidney tissue MDA were carried out after 8 days of gentamicin treatment. Kidneys were examined using histological techniques. Blood urea and serum creatinine were increased by 896% and 461% respectively, with gentamicin, compared to saline treated group. Creatinine clearance was significantly decreased with gentamicin. Ginkgo biloba extract protected rats from gentamicin-induced nephrotoxicity. Changes in blood urea, serum creatinine and creatinine clearance induced by gentamicin were significantly prevented by Ginkgo biloba extract. There was a 177% and 374% rise in plasma and kidney tissue MDA with gentamicin, which were significantly reduced to normal with Ginkgo biloba extract. Histomorphology showed necrosis and desquamation of tubular epithelial cells in renal cortex with gentamicin, while it was normal and comparable to control with Ginkgo biloba extract. These data suggest that supplementation of Ginkgo biloba extract may be helpful to reduce gentamicin nephrotoxicity.     

Coconut products alleviate hyperglycaemic,hyperlipidimic and nephropathy indices in streptozotocin-induced diabetic wistar rats

Type 2 diabetes mellitus (T2DM) is a chronic and one of the most common metabolic diseases affecting large proportion of world population. Diabetes-induced changes in lipid and renal parameters are major risk factors contributing to diabetic complications such as diabetic nephropathy and cardiovascular diseases. Due to adverse effects associated with pharmacological intervention in the T2DM treatment, there is an increased interest in the research focussing on identifying novel plant based therapeutic agents. Here we report the effects of various coconut products on diabetic, lipid and renal parameters in streptozotocin (STZ)-induced diabetic rat model. Diabetic rats demonstrated a significant increase in serum glucose, and glycated haemoglobin levels (HbA1c). Lipid parameters including triglycerides, total cholesterol, low density lipoprotein cholesterol (LDL-cholesterol) and very low density lipoprotein cholesterol (VLDL-cholesterol) were found to be significantly increased, while high density lipoprotein cholesterol (HDL-cholesterol) was significantly declined in diabetic rats. Diabetic rats also displayed increased serum and kidney creatinine, urea, and total protein levels and increased urine glucose, urea, albumin and creatinine levels. Contrastingly, treatment with virgin and filtered coconut oils, coconut water and coconut milk resulted in a significant reversal in the levels of above studied parameters in diabetic rats. Further, these coconut products markedly prevented diabetes induced histopathological changes in kidney tissue. Collectively, the data demonstrate the antidiabetic, hypolipidemic and renal protective properties of various coconut products and underscore the importance of regular consumption of plant based medicinal products in the treatment of T2DM and its complications.     

Comparative investigation of kidney mesangial cells from increased oxidative stress-induced diabetic rats by using different microscopy techniques

High glucose and increased oxidative stress levels are the known important mediators of diabetic nephropathy. However, the effects of these mediators on tissue damage basically due to extracellular matrix expansion in mesangial cells have yet to be fully examined within the context of early stage diabetic nephropathy. In this study, we attempted to characterize changes in mesangial cells of streptozotocin-induced diabetic rats with a comparative investigation of kidney tissue by using different microscopy techniques. The serum levels of urea and creatinine of diabetic rats, as biomarkers of kidney degeneration, decreased significantly compared to those of age-matched controls. In diabetic rats, there are increased malondialdehyde and oxidized-glutathione levels as well as reduced-glutathione and glutathione-peroxidase activity levels in renal tissue compared to those of the controls. By using light and electron microscopies, we showed that there were marked thickening in Bowman’s membrane and glomerular capillary wall, increased amount of extracellular matrix often occupying Bowman’s space, degenerations in tubules, an increased number of mesangial cells in the network of glomerular capillary walls, and increased amount of lipid accumulation in proximal tubules in the renal tissue of diabetic rats. Our confocal microscopy data confirmed also the presence of irregularity and widened in glomerular capillaries, their attachment to the Bowman’s capsule, degenerated heterochromatin, thickening in foci of glomerular basement membrane, and marked increase in mesangial cells. These results suggest that a detailed structural investigation of kidney tissue provides further information on the important role of mesangial cells in pathogenesis of diabetic nephropathy.     

Effect of Aloe vera gel extract on antioxidant enzymes and azoxymethane-induced oxidative stress in rats

The present work was undertaken with a view to study the effect of oral feeding of 2% Aloe vera gel extract (AGE) for 30 days on azoxymethane (AOM)-induced oxidative stress in rats. It was observed that AOM administration resulted in a significant increase in malondialdehyde and conjugated dienes, with reduction in hepatic glutathione (GSH), vitamin A and uric acid contents. AOM-induced reduction in hepatic GSH and uric acid was brought back to normal by AGE. There was a significant raise in hepatic catalase, superoxide dismutase and glucose-6-phosphate dehydrogenase (G-6-PD) activities as a result of feeding of the extract. Ingestion of the extract effected reduction in AOM-induced colonic GSH-peroxidase, G-6-PD and glutathione S-transferase and femur bone marrow micronuclei formation. Hence, it is suggested that Aloe vera gel extract possess the ability to reduce AOM- induced oxidative stress and toxicity in liver.     

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

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 β-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 β-cells in the nSTZ rats.     

Influence of Aloe vera on collagen characteristics in healing dermal wounds in rats

Wound healing is a fundamental response to tissue injury that results in restoration of tissue integrity. This end is achieved mainly by the synthesis of the connective tissue matrix. Collagen is the major protein of the extracellular matrix, and is the component which ultimately contributes to wound strength. In this work, we report the influence of Aloe vera on the collagen content and its characteristics in a healing wound. It was observed that Aloe vera increased the collagen content of the granulation tissue as well as its degree of crosslinking as seen by increased aldehyde content and decreased acid solubility. The type I/type III collagen ratio of treated groups were lower than that of the untreated controls, indicating enhanced levels of type III collagen. Wounds were treated either by topical application or oral administration of Aloe vera to rats and both treatments were found to result in similar effects.     

Molecular perspective and anticancer activity of medicinal plants

To evaluate phytochemical constituents from the methanolic extracts of medicinal plants Aloe castellorum and Aloe pseudorubroviolacea. The cytotoxic activity of Aloe castellorum and Aloe pseudorubroviolacea leaf extracts against Human colon cancer cell line (HCT-116) was also assessed. The two medicinal plant extracts having significant cytotoxic activity, meanwhile the methanolic extract of Aloe castellorum shows higher cytotoxic activity than Aloe pseudorubroviolacea extract. The Aloe castellorum shows remarkable activity against respective cell line than control. The characteristic chemical constituents of Aloe castellorum and Aloe pseudorubroviolacea leaf extracts were recognized from Gas chromatography and Mass spectrometry (GC–MS) technique. The molecular docking studies also support the cytotoxic activity.     

Antidiabetic activity of aqueous extract and non polysaccharide fraction of Cynodon dactylon Pers

Petroleum ether (60 degrees-80 degrees C), chloroform, acetone, ethanol, aqueous and crude hot water extracts of the whole plant of C. dactylon and the two fractions of aqueous extract were tested for antihyperglycaemic activity in glucose overloaded hyperglycemic rats and in alloxan induced diabetic model at two-dose levels, 200 and 400 mg/kg (po) respectively. The aqueous extract of C. dactylon and the non polysaccharide fraction of aqueous extract were found to exhibit significant antihyperglycaemic activity and only the non polysaccharide fraction was found to produce hypoglycemia in fasted normal rats. Treatment of diabetic rats with aqueous extract and non polysaccharide fraction of the plant decreased the elevated biochemical parameters, glucose, urea, creatinine, serum cholesterol, serum triglyceride, high density lipoprotein, low density lipoprotein, haemoglobin and glycosylated haemoglobin significantly. Comparatively, the non polysaccharide fraction of aqueous extract was found to be more effective than the aqueous extract.     

A comparative study of the effects of topical application of Aloe vera, thyroid hormone and silver sulfadiazine on skin wounds in Wistar rats

Many research studies report the healing effects of Aloe Vera, thyroid hormone cream and silver sulfadiazine. However, the effects of these therapeutic agents are not well understood and have not been compared in one study. This study aimed at investigating the effects of topical application of an Aloe vera gel, a thyroid hormone cream and a silver sulfadiazine cream on the healing of skin wounds surgically induced in Wistar rats for determining the treatment of choice. In a randomized controlled trial, twelve male rats, aged 120 days and with a mean weight of 250 to 300 g, were divided randomly into 5 groups based on drug treatments: Aloe vera gel (AV), thyroid hormone cream (TC), silver sulfadiazine 1% (S), vehicle (V) and control. To evaluate the efficacy of each treatment technique, a biomechanical approach was used to assess tensile stress after 14 days of treatment. Tensile stress was significantly improved in the Aloe vera gel group as compared with the other four groups (P≤0.05). While the other treatment options resulted in better healing than the control group, this difference was not significant. We conclude that Aloe vera topical application accelerated the healing process more than thyroid hormone, silver sulfadiazine and vehicle in surgically induced incisions in rats.