Antidiabetic, hypolipidemic and histopathological analysis of Dillenia indica (L.) leaves extract on alloxan induced diabetic rats

ObjectiveTo investigate antidiabetic, hypolipidemic histopathological analysis of Dillenia indica (D. indica) methanolic leaves (DIME) extract in alloxan induced diabetic rat by administering oral doses (250 and 500 mg/kg body weight).MethodsBlood glucose levels were measured using blood glucose test strips with elegance glucometer on weekly intervals till the end of study (i.e. 3 weeks). Other parameters e.g. liver profile, renal profile and total lipid levels were determined in normal and alloxan induced diabetic rats after oral administration of the extract for 21 days. Histopathological changes in diabetic rat organs (pancreas, liver and kidney) were also observed after extract treatment.ResultsDaily oral administration DIME (250 and 500 mg/kg body weight) and glibenclamide (10 mg/kg) showed beneficial effects on blood glucose level (P < 0.001) as well as improving kidney, liver functions and hyperlipidaemia due to diabetes. The extract treatment also showed to enhanced serum insulin level and body weight of diabetic rats as compared to diabetic control group. Furthermore, the extract has a favorable effect on the histopathological changes of the pancreas, liver and kidney in alloxan induced diabetes.ConclusionsD. indica possess antidiabetic property as well improve body weight, liver profile, renal profile and total lipid levels. DIME has also favorable effect to inhibit the histopathological changes of the pancreas and kidney in alloxan induced diabetes.     

Lipid abnormalities in streptozotocin-diabetes: Amelioration by Morus indica L. cv Suguna leaves

AIM:

To observe the influence of mulberry (Morus indica L. cv Suguna) leaves on lipid abnormalities in STZ-diabetic rats.

MATERIALS AND METHODS:

Treatment with dried mulberry leaf powder for a period of 8 weeks in hyperglycemic and hyperlipidemic STZ-diabetic rats.

RESULTS:

Mulberry leaves regulated fasting blood glucose, ameliorated the abnormalities in lipid profile as indicated by significant (P<0.01) decrease in serum triglycerides, phospholipids, cholesterol and plasma free fatty acids by 50, 6, 31 and 22% respectively in STZ- diabetic rats compared to diabetic control rats which had significantly (P<0.01) raised levels of triglycerides, phospholipids, cholesterol and free fatty acids than the normal control rats. A marked increase in fecal bile acids (154%) was observed in mulberry treated diabetic rats compared to the diabetic control group indicating conversion of cholesterol to bile acids. In addition, mulberry supplementation significantly lowered LDL-C (67%) and VLDL-C (44%) levels and increased HDL-C (53%) and also decreased atherogenic index (58%) significantly when compared to the diabetic control group.

CONCLUSION:

Besides the diabetic rats, mulberry leaves affected lipid profile in normal rats also indicating hypolipidemic effect as a result of the synergistic action of bioactive compounds.     

Diuretic and antioxidant activities of the aqueous extract of leaves of Cassia occidentalis(Linn.) in rats

Objective: To assess the putative diuretic and antioxidant properties of Cassia occidentalis(C. occidentalis) leaves' aqueous extract. Methods: Adult rats were administered with C. occidentalis leaves aqueous extract acutely(24-h) and subchronically(7 d), at doses 80, 160, 240, 320, and 400 mg/kg(per os). Negative control group received only an equivalent volume of distilled water, while the two positive control groups received the diuretic drugs furosemide(20 mg/kg, i.p.) and hydrochlorothiazide(HCTZ, 20 mg/kg, i.p.). Urinary elimination of electrolytes in response to treatments was evaluated, together with changes in concentrations of creatinine, urea, aldosterone, glucose, and albumin in urine and plasma. Various urinary indicators of kidney function and plasmatic markers of oxidative stress were also assessed. Results: The acute administration of C. occidentalis increased the urinary excretion of 107.58% at the higher dose tested, compared to negative control. The reference drugs furosemide and HCTZ induced increases of 84.27 % and 48.05 %, respectively. Acutely, the extract induced Na+ and Cl- elimination, whereas subchronically an increase in K+ elimination was also observed. The extract also improved the kidney function indexes and oxidative stress markers. These effects were dose-dependent and comparable with positive control observations. Conclusions: Our i ndings strongly suggest that C. occidentalis aqueous extract has diuretic and antioxidant activities, and deserves further studies considering the potential for the treatment of hypertension.     

Antidiabetic effects of sage (Salvia officinalis L.) leaves in normal and streptozotocin-induced diabetic rats

BackgroundSage (Salvia officinalis L.) has a wide range of biological activities, such as anti-oxidative properties, anti-bacterial, hypoglycemic, anti-inflammatory, fungistatic, virustatic, astringent, eupeptic and anti-hydrotic effects. This study was designed to examine the antidiabetic effect of sage ethanolic extract in normal and streptozotocin-induced diabetic rats.MethodsOral administration of sage extract (0.1, 0.2, and 0.4 g/kg body weight) and glibenclamide (600 μg/kg) for 14 days on the level of serum glucose, triglycerides, total cholesterol, urea, uric acid, creatinine, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in normal and streptozotocin-induced diabetic rats were evaluated.ResultsOral administration of 0.2 and 0.4 g/kg body wt. of the sage extract for 14 days exhibited a significant reduction in serum glucose, triglycerides, total cholesterol, urea, uric acid, creatinine, AST, ALT and increased plasma insulin in streptozotocin-induced diabetic rats but not in normal rats. Glibenclamide was used as reference and showed similar antidiabetic effect.ConclusionsIt is concluded that the traditional use of S. officinalis as an antidiabetic agent is justified and that extracts from this plant show a dose-dependent activity which is comparable to the standard antidiabetic drug glibenclamide.     

Role of antioxidant enzymes and small molecular weight antioxidants in the pathogenesis of age-related macular degeneration (AMD)

Cells in aerobic condition are constantly exposed to reactive oxygen species (ROS), which may induce damage to biomolecules, including proteins, nucleic acids and lipids. In normal circumstances, the amount of ROS is counterbalanced by cellular antioxidant defence, with its main components—antioxidant enzymes, DNA repair and small molecular weight antioxidants. An imbalance between the production and neutralization of ROS by antioxidant defence is associated with oxidative stress, which plays an important role in the pathogenesis of many age-related and degenerative diseases, including age-related macular degeneration (AMD), affecting the macula—the central part of the retina. The retina is especially prone to oxidative stress due to high oxygen pressure and exposure to UV and blue light promoting ROS generation. Because oxidative stress has an established role in AMD pathogenesis, proper functioning of antioxidant defence may be crucial for the occurrence and progression of this disease. Antioxidant enzymes play a major role in ROS scavenging and changes of their expression or/and activity are reported to be associated with AMD. Therefore, the enzymes in the retina along with their genes may constitute a perspective target in AMD prevention and therapy.     

血管紧张素受体拮抗剂对糖尿病大鼠肾脏抗氧化酶的影响

目的：探讨血管紧张素受体拮抗剂氯沙坦对糖尿病大鼠肾脏抗氧化酶的影响。方法：将实验动物分为正常对照组、糖尿病对照组及氯沙坦治疗组。检测各组第6、12周的血糖、血肌酐 、尿蛋白、尿肌酐、肾组织中丙二醛（MDA）、超氧化物歧化酶（铜锌SOD）、过氧化氢酶（CAT）和谷胱甘肽过氧化物酶（GSH－PX）水平。结果：氯沙坦治疗组较非治疗组尿蛋白排泄量、血肌酐水平、血脂、血胆固醇水平明显下降（P＜0.05）,非治疗组肾脏丙二醛含量明显增加,肾脏抗氧化酶活性（Cu、Zn-SOD,CAT和GSH-PX）明显降低,经氯沙坦治疗后,糖尿病大鼠肾脏的丙二醛含量明显降低,肾脏的抗氧化酶活性增加。结论：糖尿病大鼠肾脏的氧化损伤在糖尿病肾病发展中起重要作用,而氯沙坦可能通过增加肾脏的抗氧化酶活性从而对糖尿病大鼠肾脏起保护作用。     

Hepatoprotective effects of Nigella sativa L and Urtica dioica L on lipid peroxidation, antioxidant enzyme systems and liver enzymes in carbon tetrachloride-treated rats

AIM: To investigate the effects of Nigella sativa L (NS) and Urtica dioica L (UD) on lipid peroxidation, antioxidant enzyme systems and liver enzymes in CCl4-treated rats. METHODS: Fifty-six healthy male Wistar albino rats were used in this study. The rats were randomly allotted into one of the four experimental groups: A (CCU-only treated), B (CCU+UD treated), C (CCU+NS treated) and D (CCl4+UD+NS treated), each containing 14 animals. All groups received CCU (0.8 mL/kg of body weight, sc, twice a week for 60 d). In addition, B, C and D groups also received daily i.p. injections of 0.2 mL/kg NS or/and 2 mL/kg UD oils for 60 d. Group A, on the other hand, received only 2 mL/kg normal saline solution for 60 d. Blood samples for the biochemical analysis were taken by cardiac puncture from randomly chosen-seven rats in each treatment group at beginning and on the 60th d of the experiment. RESULTS: The CCl4 treatment for 60 d increased the lipid peroxidation and liver enzymes, and also decreased the antioxidant enzyme levels. NS or UD treatment (alone or combination) for 60 d decreased the elevated lipid peroxidation and liver enzyme levels and also increased the reduced antioxidant enzyme levels. The weight of rats decreased in group A, and increased in groups B, C and D. CONCLUSION: NS and UD decrease the lipid peroxidation and liver enzymes, and increase the antioxidant defense system activity in the CCl4-treated rats.     

Effect of L-carnitine on brain lipid peroxidation and antioxidant enzymes in old rats

The effect of L-carnitine on lipid peroxidation and enzymatic antioxidants, such as superoxide dismutase, catalase, and glutathione peroxidase, was evaluated in brain regions of young and old rats. In all brain regions except the hypothalamus, lipid peroxidation was higher for old rats than for young control rats. The activity of superoxide dismutase, glutathione peroxidase, and catalase was lower in the striatum, cerebral cortex, and hippocampus, but no difference was observed in the hypothalamus and cerebellum. L-Carnitine administration (intraperitoneally) prevented thiobarbituric acid-reactive substance formation in the cerebral cortex, cerebellum, hypothalamus, hippocampus, and striatum of 24-month-old rats. Administration of L-carnitine reversed the age-associated changes in a duration-dependent manner. Results suggest that the neuroprotective effect on the brains in old rats was achieved by the elevation of antioxidants with L-carnitine.     

褪黑素对糖尿病大鼠肾脏抗氧化物酶的影响

与正常大鼠比较,STZ诱发的糖尿病大鼠肾与血清的丙二醛水平升高,以及抗氧化物酶活性降低,在褪黑素治疗后均见明显改善,同时伴随出现尿白蛋白排泄率、血尿酸、血脂谱以及肾重对体重的比值等的降低。     

Effects of probucol on changes of antioxidant enzymes in adriamycin-induced cardiomyopathy in rats

OBJECTIVE: The clinical usefulness of doxorubicin (adriamycin, ADR) is restricted by the risk of developing congestive heart failure. Probucol has been reported to completely prevent ADR cardiomyopathy without interfering with its antitumor effects. The current study investigated the effects of ADR and probucol on antioxidant enzyme gene expression during adriamycin-induced cardiomyopathy in a rat model. METHODS: The mRNA abundance by Northern and immunoreactive protein levels by Western blotting of myocardial antioxidant enzymes, glutathione peroxidase (GSHPx), manganese superoxide dismutase (MnSOD) and catalase (CAT) were examined in relation to the enzyme activities in hemodynamically assessed control and treated animals. RESULTS: At 3 weeks post-treatment duration, ADR caused heart failure which was prevented by probucol. MnSOD mRNA abundance as well as protein levels were depressed by ADR treatment by 45% and 20%, respectively, and this change was prevented by probucol. However, the mRNA and protein levels of GSHPx and CAT were not significantly changed by ADR or probucol. ADR had no effect on SOD activity but this enzyme activity was increased by probucol and probucol plus ADR. GSHPx enzyme activity was decreased and oxidative stress as indicated by TBARS was increased by ADR and these changes were also modulated by probucol. CONCLUSION: An increase in oxidative stress, GSHPx inactivation and MnSOD downregulation during ADR cardiomyopathy were prevented by probucol treatment.     

Lipid peroxidation, some extracellular antioxidants, and antioxidant enzymes in serum of patients with rheumatoid arthritis

The aims of our study were to assess whether the increased oxidative stress in inflamed joints is reflected by serum lipid peroxidation and also to check alterations in the levels of extracellular antioxidants and antioxidant enzyme activities in patients with rheumatoid arthritis. Serum malondialdehyde and ceruloplasmin levels and the activity of CuZn superoxide dismutase were higher, while transferrin levels and the activities of glutathione peroxidase and catalase were lower in patients (n = 37) than in healthy controls (n = 30). Disease activity score correlated positively with serum malondialdehyde level and CuZn superoxide dismutase activity. Probably, superoxide radicals in serum could be dismutated to produce hydrogen peroxide by increased CuZn superoxide dismutase activity, but hydrogen peroxide could not have been detoxified due to decreased activities of serum glutathione peroxidase and catalase. Hydrogen peroxide possibly converted to hydroxyl radical by iron due to lower transferrin level might have led to increased serum lipid peroxidation in patients with rheumatoid arthritis.     

RNA metabolism in senescing detached betel (Piper betle L.) leaves.

This study aimed to examine the changes in the metabolism of RNA taking place in the detached petiolated betel leaf and to compare them with those occurring in depetiolated/ demidribbed leaves. While RNA level declined continuously, the activity of RNases increased manifold as the leaf senesced. These events were, however, slowed down due to depetiolation/demidribbing treatments. Pulse feeding experiments showed that the ability of the tissue to synthesise RNA declined during senescence. Precursor incorporation in fast senescing petiolated leaves was poorer than in treated slow senescing ones. It is concluded that depetiolation/demidribbing-induced delay in the onset of senescence is accompanied by relatively higher synthesis and lower degradation of RNA.     

Hypoglycemic effect of Du-zhong (Eucommia ulmoides Oliv.) leaves in streptozotocin-induced diabetic rats

The current study investigated whether Du-zhong (Eucommia ulmoides Oliv.) leaves could improve the hyperglycemia in streptozotocin (STZ)-induced diabetic rats. Male Sprague-Dawley rats were divided into a non-diabetic group (NDM), diabetic group (DM), diabetic group supplemented with powdered Du-zhong leaves (DM-PDZ) and diabetic group supplemented with a water extract of the powdered Du-zhong leaves (DM-WDZ). Diabetes was induced by injecting STZ (70 mg/kg B.W., i.p.). The powdered Du-zhong leaves or its powdered water extract was add to a standard diet based on 1% dried Du-zhong leaves (1 g PDZ/100 g diet and 0.187 g WDZ/100 g diet, respectively) for 3 weeks. Body weight was significantly higher in both types of Du-zhong leaves supplemented groups than in the DM group. The blood glucose levels were significantly lower in the DM-PDZ and DM-WDZ groups than in the DM group (20.05+/-0.88 and 18.96+/-1.23 mmol/l versus 24.42+/-1.07 mmol/l, P<0.05), whereas the plasma insulin and C-peptide levels were significantly higher in the PDZ and WDZ supplemented groups than in the DM group (7.45+/-0.27 and 7.62+/-0.69 microl U/ml versus 3.75+/-0.27 microl U/ml for the plasma insulin, and 224.52+/-14.6 and 239.76+/-15.52 pmol/l versus 166.5+/-10.4 pmol/l for the plasma C-peptide, respectively, P<0.05). The supplementation of PDZ and WDZ also resulted in lower plasma urea nitrogen levels compared to the DM group. Du-zhong leaves supplement seemed to be helpful to preserve the normal histological appearance of pancreatic islets as well as to preserve insulin-positive beta-cells but it did not reverse the effect of STZ to a great extent. Accordingly, the reduction in plasma glucose by the powdered Du-zhong leaves and its water extract is quite small but significant, nevertheless, this was occurred with simultaneous the increase in plasma insulin and C-peptide. They improved hyperglycemia and seemingly enhance the function of pancreatic beta-cells in STZ-induced diabetic rats.     

Evaluation of antihyperglycemic and antioxidant activities of Saraca asoca (Roxb.) De Wild leaves in streptozotocin induced diabetic mice

ObjectiveTo investigate the antihyperglycemic and antioxidant properties of the petroleum Ether, chloroform and methanol extract ofSaraca asoca (Roxb.) De Wild (S. asoca) leaves in mice.MethodsSwiss albino mice were made diabetic by a single dose of streptozotocin (150 mg/kg i.p.). Blood glucose levels and body weights of mice were measured using on weekly intervals i.e. day 0, 7, 14 and 21 after daily administration of all extracts at doses of 250 and 500 mg/kg. Other biochemical parameters such as serum cholesterol, triglycerides, HDL-cholesterol, VLDL-cholesterol, LDL-cholesterol, urea, creatinin and proteins levels were also measured at the end of study. The effects of all extracts were also noticed on vital organs e.g. liver, kidney and pancreas. The antioxidant potential of all extracts was also determined by DPPH and H₂O₂ radical scavenging in vitro methods.ResultsOral administration of the extracts for 21 days caused a significant (P <0.01) reduction in blood glucose levels in diabetic mice. Among all the extracts, methanol extract showed better results. The body weight of diabetic animals was also improved after daily administration of extracts. All the extracts also improved other altered biochemical parameters associated with diabetes. Furthermore, the extracts have favorable effects on the histopathological changes of the pancreas, liver and kidney in STZ induced diabetic mice. All the extracts showed significant (P <0.05) antioxidant activity at the dose of 500 µg/ml.ConclusionsS. asoca possesses antihyperglycemic and antioxidant properties as well improves body weight, liver profile, renal profile and total lipid levels. It can justify folklore uses of the plant in diabetes.     

桑叶提取物对糖尿病小鼠心肌保护作用的研究

目的 基于氧化应激探究桑叶提取物(MLE)对糖尿病小鼠心肌保护作用及机制.方法 采用链脲佐菌素(STZ)及高糖脂饲料(HFD)诱导的糖尿病小鼠模型,以二甲双胍(Met,200 mg/kg)为阳性对照,分别给予100 mg/kg、200 mg/kg、400 mg/kg的桑叶提取物对糖尿病小鼠灌胃给药,干预12周后检测各组...     

The effects of estrogen and raloxifene treatment on antioxidant enzymes in brain and liver of ovarectomized female rats

Recent studies documented that estrogen have antioxidant properties in-vitro, there are conflicting results on the effect of estrogen in vivo. We aimed to investigate the effects of estradiol and Raloxifene on the antioxidant enzyme [superoxide dismutase (SOD) and catalase (CAT)] activities and MDA levels in brain and liver homogenates of ovariectomized female rats. Twelve weeks after ovariectomy, female Sprague-Dawley rats (n = 26) were divided into three groups: (1) Ovariectomized placebo group (n = 6) was given physiologic saline. (2) Estrogen group (n = 10) was given Ethynyl estradiol, 0.1 mg/kg sc. (3) Raloxifene group (n = 10) was given raloxifene, 1 mg/kg sc during 8 weeks. Ten rats were used as naive controls without any treatment (Sham operated group, n = 10). Ovariectomy lead to an increase in the CAT activities in liver tissue samples compared to the sham group (p = 0.056, Mann-Whitney test). While estrogen treatment reversed to normal levels of CAT activities, raloxifene remained as ineffective. Superoxide dismutase activities and MDA levels in liver were remained unchanged in all groups. There was no significant change in the brain tissue SOD and CAT activities between the control ovariectomy, estrogen treated, and raloxifen treated groups. We determined an increase in MDA levels in brain of ovariectmised rat (p = 0.02). While raloxifene treatment reversed to normal levels of MDA (p = estrogen treatment failed. Our data showed that estrogen may play a role in regulation of CAT and SOD activities in liver due to its antioxidative effects. We can suggest estrogen and raloxifene exert their antioxidative effects in brain rather than liver. Since Raloxifene's effect is more clear than estradiol, raloxifene may be suggested primarily for treatment and/or prevention of diseases which can be resulted from oxidative stress in postmenopausal women.     

Antihyperglycemic and antioxidant effects of Solanum xanthocarpum leaves (field grown & in vitro raised) extracts on alloxan induced diabetic rats

ObjectiveTo investigate antidiabetic efficacy of the extract of field grown and in vitro raised leaves of Solanum xanthocarpum (S. xanthocarpum) against alloxan induced diabetic rats.MethodsThe antidiabetic activity of the crude methanol extracts of the field grown and in vitro raised leaves of S. xanthocarpum at different concentrations (100–200 mg/kg bw) was tested against alloxan induced diabetic rats. The antidiabetic efficacy was validated through various biochemical parameters and the antioxidant effect was also determined. The phytochemical analyses of field grown S. xanthocarpum and in vitro rasied S. xanthocarpum leaves were done by estimating their chlorophyll, carotenoids, total sugar, protein, amino acid and minerals contents.ResultsThe results revealed that the methanol extracts of both the leaves (field grown and in vitro raised) of S. xanthocarpum was efficient anti hyperglycemic agents at a concentration of 200 mg/kg bw and posses potent antioxidant activity. However, the extracts of in vitro rasied S. xanthocarpum raised leaves exhibit higher efficacy than the field grown leaves in all tested concentrations. Proximal composition and mineral analysis of S. xanthocarpum revealed higher concentration of contents in in vitro rasied S. xanthocarpum than field grown S. xanthocarpum.ConclusionsFrom the results it can be concluded that the leaves extracts of S. xanthocarpum can be a potential candidate in treating the hyperglycemic conditions and suits to be an agent to reduce oxidative stress.     

A comparative study on the antioxidant activity of methanolic leaf extracts of Ficus religiosa L,Chromolaena odorata (L.) King & Rabinson,Cynodon dactylon (L.) Pers. and Tridax procumbens L.

ObjectiveTo compare the antioxidative effects of the methanolic leaf extracts of Ficus religiosa (F. religiosa), Chromolaena odorata (C. odorata), Cynodon dactylon (C. dactylon) and Tridax procumbens (T. procumbens) as well as the contents of antioxidants in the extracts.MethodsTotal phenol and total flavanoid contents were measured according to the standard procedures. The total antioxidant capacity was determined using the phosphomolybdenum method. Reducing power was determined by the potassium ferricyanide reducing method. The free radical scavenging activity was measured by 2,2′-Diphenyl-1-picrylhydrazyl (DPPH) assay.ResultsQuantitative phytochemical analysis of total phenol content showed that C. odorata had the highest content of phenolic compounds significantly followed by F. religiosa, T. procumbens and C. dactylon. As for the total flavanoids content, F. religiosa had the highest content, followed by C. odorata, T. procumbens and C. dactylon. Study on the total antioxidant capacity revealed that F. religiosa, C. dactylon and C. odorata showed higher total antioxidant capacity. T. procumbens showed the lowest capacity. Meanwhile, T. procumbens and C. odorata have the highest reducing power activity followed by F. religiosa and C. dactylon. The results of DPPH radical scavenging activity indicated that T. procumbens induced the largest elevation as the concentration of its extract increased, followed by C. odorata and F. religiosa and C. dactylon.ConclusionsThe present study demonstrates the antioxidative capacity of all the four plant species. Of all the plants, C. odorata, a perennial weed plant showed potentially a high antioxidant activity, with higher phenolic and flavonoids contents. The data suggest that C. odorata can be best utilized in developing bioantioxidants.