Alterations in the blood glucose, serum lipids and renal oxidative stress in diabetic rats by supplementation of onion (Allium cepa. Linn)

This study examined the anti-diabetic effect of onion (Allium cepa. Linn) in the streptozotocin (STZ)-induced diabetic rats. Male Sprague-Dawley rats were divided into normal rats fed control diet or supplemented with onion powder (7% w/w) and diabetic rats fed control diet or supplemented with onion powder. Diabetes was induced by a single injection of STZ (60 mg/kg, ip) in citrate buffer. The animals were fed each of the experimental diet for 5 weeks. Blood glucose levels of rats supplemented with onion were lower than those of rats fed control diet in the diabetic rats. Onion also decreased the total serum lipid, triglyceride, and atherogenic index and increased HDL-cholesterol/total cholesterol ratio in the diabetic rats. Glutathione peroxidase, glutathione reductase and glutathione S-transferase activities were high in the diabetic rats compared to normal rats and reverted to near-control values by onion. These results indicate that onion decreased blood glucose, serum lipid levels and reduced renal oxidative stress in STZ-induced diabetic rats and this effect might exert the anti-diabetic effect of onion.     

In vitro intestinal glucose uptake is inhibited by galactomannan from Canadian fenugreek seed (Trigonella foenum graecum L) in genetically lean and obese rats

Galactomannan, a soluble fiber, has been reported to reduce postprandial blood glucose response. Using this fiber, extracted from Canadian-grown fenugreek seeds (Trigonella foenum graecum L), we conducted an in vitro study to determine if galactomannan affects intestinal glucose uptake in genetically determined lean and obese rats. The segments of jejunum and ileum from these animals were incubated with labeled glucose (2 or 32 mmol/L) in the presence of different concentrations of galactomannan ranging from 0.1% to 0.5% (wt/wt). The uptake of low or high concentration of glucose was significantly and progressively reduced by increasing concentrations of galactomannan in both lean and obese rats. No significant difference was observed in the uptake of glucose between the 2 groups. The viscosity of various concentrations of galactomannan solutions was determined after stirring for 60 minutes at a temperature-controlled (37°C) fixed sheer rate of 1.29 (1/s). The inhibitory effect of galactomannan on glucose uptake was found to be in parallel with the degree of viscosity of the fiber solutions. These results suggest that the galactomannan, because of its viscous property, has the potential to reduce intestinal absorption of low or high concentrations of glucose and hence for the benefit of blood glucose management.     

燕麦β-葡聚糖对小鼠肠道菌群的影响

  目的  探讨燕麦β–葡聚糖对糖尿病大鼠肾病进展的干预作用及机制。  方法  采用链脲佐菌素（65 mg/kg）一次性腹腔注射 + 单侧肾切除的方式构建糖尿病肾病大鼠模型,造模成功后随机分为4组,分别为模型组（蒸馏水）,和低、中、高剂量燕麦β–葡聚糖组（0.275、0.550、1.100 g/kg）,每组12只;同时另取10只大鼠行假手术并灌胃蒸馏水,为对照组;干预8周。采集血液和尿液,检测尿素氮（BUN）、尿酸（UA）、血肌酐（CR）和血清炎症因子白细胞介素–6（IL-6）、血管内皮生长因子（VEGF）水平,并取肾脏做病理组织检测。  结果  与对照组比较,模型组大鼠血清尿素氮、VEGF、IL-6水平[分别为（14.80 ± 3.63）mmol/L、（312.54 ± 13.39）、（145.96 ± 5.67）ng/L]明显升高（P < 0.05）;与模型组比较,燕麦β–葡聚糖0.275 g/kg组大鼠血清尿素氮水平[（10.39 ± 2.04）mmol/L]明显下降,燕麦β–葡聚糖0.550 g/kg组大鼠血清VEGF及IL-6水平[分别为（269.94 ± 16.70）、（129.71 ± 6.48）ng/L]明显下降,差异有统计学意义（P < 0.05）;与模型组比较,燕麦β–葡聚糖组大鼠肾脏组织结构损伤明显减轻。  结论  燕麦β–葡聚糖可有效改善糖尿病肾病大鼠肾功能,延缓肾脏组织结构损伤,其机制可能与下调炎症相关因子表达水平,改善机体炎症状态有关。     

Mulberry leaf extract restores arterial pressure in streptozotocin-induced chronic diabetic rats

Free radical-induced vascular dysfunction plays a key role in the pathogenesis of vascular disease found in chronic diabetic patients. Morus alba (MA) leaf extract is promoted for good health especially in diabetic patients. Interestingly, antidiabetic and antioxidant activities of MA have been reported in experimental animals. Thus, the hypothesis of this study was that the long-term treatment with MA could improve vascular reactivity of chronic diabetic rats. To test this hypothesis, we examined the effect of long-term treatment with MA on the vascular responses to vasoactive agents in streptozotocin-induced chronic diabetic rats. The diabetic rats were either orally administered with distilled water, MA (0.25, 0.5 and 1 g/kg per day) or subcutaneously injected with insulin (4 U/kg per day) for 8 weeks. After each treatment, the fasting blood glucose, blood pressure, vascular responses to vasoactive agents and tissue malondialdehyde were examined. Morus alba at the doses of 0.5 and 1 g/kg, which significantly reduced blood glucose level, also significantly decreased the high blood pressure in diabetic rats. Vascular responses of the chronic diabetic rats to vasodilators, acetylcholine (3-30 nmol/kg) and sodium nitroprusside (1-10 nmol/kg) were significantly suppressed by 26% to 44% and 45% to 77% respectively, whereas those to vasoconstrictor, phenylephrine (0.01-0.1 μmol/kg) were significantly increased by 23% to 38% as compared to normal rats. Interestingly, the administration of 0.5 and 1 g/kg MA or 4 U/kg insulin significantly restored the vascular reactivities of diabetic rats. Moreover, 8 weeks of diabetes resulted in the elevation of malondialdehyde content in tissues (liver, kidney, heart, and aorta), and MA treatment significantly lessened this increase. These results provide the first evidence for the efficacy of MA in restoring the vascular reactivity of diabetic rats, the mechanism of which may associate with the alleviation of oxidative stress.     

White button mushroom (Agaricus bisporus) lowers blood glucose and cholesterol levels in diabetic and hypercholesterolemic rats

Agaricus bisporus (white button mushroom; WBM) contains high levels of dietary fibers and antioxidants including vitamin C, D, and B₁₂; folates; and polyphenols that may provide beneficial effects on cardiovascular and diabetic diseases. The objective of this study was to examine the hypothesis that intake of the fruiting bodies of WBM regulates anticholesterolemic and antiglycemic responses in rats fed a hypercholesterolemic diet (0.5% cholesterol; 14% fat) and rats with type 2 diabetes induced by injection of streptozotocin (STZ) (50 mg/kg body weight), respectively. The STZ-induced diabetic male Sprague-Dawley rats fed the Agaricus bisporus powder (ABP; 200 mg/kg of body weight) for 3 weeks had significantly reduced plasma glucose and triglyceride (TG) concentrations (24.7% and 39.1%, respectively), liver enzyme activities, alanine aminotransferase and aspartate aminotransferase (11.7% and 15.7%, respectively), and liver weight gain (P < .05). In hypercholesterolemic rats, oral feeding of ABP for 4 weeks resulted in a significant decrease in plasma total cholesterol (TC) and low-density lipoprotein (LDL) (22.8% and 33.1%, respectively) (P < .05). A similar significant decrease in hepatic cholesterol and TG concentrations was observed (36.2% and 20.8%, respectively) (P < .05). Decrease in TC, LDL, and TG concentrations was accompanied by a significant increase in plasma high-density lipoprotein concentrations. It was concluded that A bisporus mushroom had both hypoglycemic and hypolipidemic activity in rats.     

Hypoglycemic and hypolipidemic effects of Saururus chinensis Baill in streptozotocin-induced diabetic rats

Saururus chinensis Baill was reported to inhibit α-glucosidase in vitro and flatten postprandial increase in blood glucose in streptozotocin (STZ)-induced diabetic rats. We studied the effect of chronic consumption of S. chinensis Baill on blood glucose and lipid profile in STZ-induced diabetic male rats fed high fat diet. Male rats weighing 100-120 g were fed 30% fat diet with and without 10% freeze-dried leaves of S. chinensis Baill for 7 weeks after 1 week of adaptation. The rats were rendered diabetic by intravenous injection of STZ (60 mg/kg) after 6-week feeding of the assigned diets. At 1 week after the injection, the rats were sacrificed after an overnight fast. Plasma glucose (380.2 ± 14.4 mg/dL), total cholesterol (93.9 ± 7.9 mg/dL) and triglyceride levels (123.6 ± 7.5 mg/dL) of the S. chinensis Baill group were significantly lower than those of the control group (418.1 ± 12.0 mg/dL, 119.9 ± 9.4 mg/dL, 152.0 ± 10.3 mg/dL, respectively, p<0.05). Chronic consumption of S. chinesis Baill significantly decreased maltase activity of the small intestinal mucosa (120.1 ± 8.7 U/g protein) compared with the control group (96.8 ± 7.0 U/g protein, p<0.05). These results suggest that S. chinensis Baill have hypoglycemic and hypolipidemic effects by inhibiting α-glucosidase activity in the animal model of diabetes mellitus.     

Mogrosides extract from Siraitia grosvenori scavenges free radicals in vitro and lowers oxidative stress,serum glucose,and lipid levels in alloxan-induced diabetic mice

This study evaluated the supplementation of a mogrosides extract (MG) from fruits of Siraitia grosvenori on reducing oxidative stress, hyperglycemia, and hyperlipidemia in alloxan-induced diabetic mice. The oxygen free radical scavenging activity of MG was also assessed in vitro. After induction of diabetes, a significant increase in the levels of serum glucose, total cholesterol (TC), triacylglycerol (TG), and hepatic malondialdehyde (MDA) as well as a reduction in the level of hepatic high-density lipoprotein cholesterol (HDL-C) associated with diminution of the corresponding antioxidant enzymes, such as glutathione peroxidase (GSH-Px) and superoxide dismutase, were observed in all diabetic mice. Treatment of diabetic mice with MG (100, 300, and 500 mg/kg ) for 4 weeks significantly decreased serum glucose, TC, TG, and hepatic MDA levels (P < .05), whereas it increased serum HDL-C level and reactivated the hepatic antioxidant enzymes (P < .05) in alloxan-induced diabetic mice (P < .05). The hypoglycemic, hypolipidemic, and antioxidative activities of MG (100 mg/kg treatment) were all higher compared with all other diabetic groups and were similar to that observed for XiaoKeWan-pill (894 mg/kg; Guangzhou Zhongyi Pharmaceutical Co., Ltd., Guangzhou, China), a Chinese traditional antidiabetic drug. Antioxidant capacity evaluated in vitro showed that MG and mogroside V, which was the main component of MG, possessed strong oxygen free radical scavenging activities. These results demonstrate that the extract may have capacity to inhibiting hyperglycemia induced by diabetes, and the data suggest that administration of the extract may be helpful in the prevention of diabetic complications associated with oxidative stress and hyperlipidemia. We conclude that the extract should be evaluated as a candidate for future studies on diabetes mellitus.     

Effect of butanol fraction from Cassia tora L. seeds on glycemic control and insulin secretion in diabetic rats

Cassia tora L. seeds have previously been reported to reduce blood glucose level in human and animals with diabetes. In the present study, the effects of Cassia tora L. seed butanol fraction (CATO) were studied on postprandial glucose control and insulin secretion from the pancreas of the normal and diabetic rats. Diabetes was induced by an i.p. injection of Streptozotocin (55 mg/kg BW) into the male Sprague-Dawley rats. The postprandial glucose control was monitored during a 240 min-period using a maltose loading test. In normal rats, rats fed CATO (20 mg/100 g BW/d) showed lower postprandial glucose levels in all the levels from 30 min up to 180 min than those in the control rats without CATO (p<0.05). In diabetic rats, those levels in the CATO group seemed to be lower during the 30~180 min, but only glucose level at 30 min showed significant difference compared to that in the control group. Moreover, CATO delayed the peak time of the glucose rise in both normal and diabetic rats in the glucose curves. On the other hand, when CATO was administered orally to the diabetic rats for 5 days, 12 hr fasting serum glucose level was decreased in the diabetic rats (p<0.05). Degree of a decrease in 12 hr fasting serum insulin levels was significantly less in the diabetic CATO rats as compared to diabetic control rats. On the last day of feeding, β cells of the pancreas were stimulated by 200 mg/dL glucose through a 40 min-pancreas perfusion. Amounts of the insulin secreted from the pancreas during the first phase (11~20 min) and the second phase (21~40 min) in the CATO fed diabetic rats were significantly greater than those in the diabetic control group (p<0.05). These findings indicated that constituents of Cassia tora L. seeds have beneficial effect on postprandial blood glucose control which may be partially mediated by stimulated insulin secretion from the pancreas of the diabetic rats.     

Renoprotective and antioxidant effects of Saururus chinensis Baill in rats fed a high-fructose diet

This study investigated the preventive effect of Saururus chinensis Baill against renal damage induced by a high-fructose diet in rats. The rats (n = 30) were fed either a cornstarch-based (65%), high-fructose (65%), or high-fructose (64.5%) diet with 0.5% S. chinensis Baill extract for 10 weeks. Twenty-four hour urine collections were obtained and the animals were sacrificed after an overnight fast. Serum urea and creatinine and urine albumin were measured using colorimetric methods, and creatinine clearance was determined. In addition, thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH), and the activity of superoxide dismutase (SOD) in the kidney were determined. Kidney samples were also examined histologically. The fructose-fed rats showed renal dysfunction, indicated by decreased creatinine clearance, increased albumin in the urine, and increased urea and creatinine in the serum. These renal function parameters were comparable to control levels in rats that consumed S. chinensis Baill. Fructose consumption increased renal TBARS and reduced GSH and SOD activity, whereas these levels were near-normal in the rats consuming S. chinensis Baill. The kidneys of fructose-fed rats showed glomerular basement membrane thickening, mesangial matrix expansion, and tubule dilation. These pathological changes were not seen in the rats that consumed S. chinensis Baill. Therefore, S. chinensis Baill effectively alleviated fructose-induced renal damage in these rats, at least partially due to antioxidant activity.     

The antihypertensive effect of ethyl acetate extract of radish leaves in spontaneously hypertensive rats

Radish (Raphanus sativus L.) is a cruciferous vegetable, and its leaves have antioxidant and anticancer properties. This study was conducted to evaluate the effects of ethyl acetate extracts from radish leaves on hypertension in 11-week-old spontaneously hypertensive rats (SHRs). The SHRs were randomly divided into 3 groups of 6 rats each on the basis of initial systolic blood pressure (SBP) and were treated with oral administration of radish leaf extract (0, 30, or 90 mg/kg body weight [bw], respectively) for 5 weeks. Six Wistar rats were used as normotensive controls. The amount of the radish leaf extract had no effect on body weight. The SBP of the SHRs showed a decreasing trend with the consumption of the radish leaf extract. In the third week, the SBP of the group fed 90 mg extract/kg bw reduced from 214 mmHg to 166 mmHg and was significantly lower than that of the normotensive and hypertensive controls. The extract did not show a significant effect on the angiotensin-converting enzyme (ACE) activity in the serum, kidney, and lung. The extract increased the concentration of NO in serum and the activities of antioxidant enzymes such as glutathione peroxidase and catalase in red blood cells (RBCs). The serum concentrations of Na⁺ and K⁺ were not significantly different between all groups. However, the fecal concentrations of Na⁺ and K⁺ increased; the fecal concentrations of Na⁺ and K⁺ for the normotensive and hypertensive controls were not different. Urinary excretion of Na⁺ was higher in the normotensive Wistar rats than in the SHRs, while that of K⁺ was not significantly different. These findings indicate that consumption of radish leaves might have had antihypertensive effects in SHRs by increasing the serum concentration of NO and fecal concentration of Na⁺ and enhancing antioxidant activities.     

L-Carnitine changes the levels of insulin-like growth factors (IGFs) and IGF binding proteins in streptozotocin-induced diabetic rat

This study investigated the effects of L-carnitine on insulin-like growth factor-I/II (IGF-I/II) and insulin-like growth factor binding proteins (IGFBPs) in streptozotocin (STZ)-induced diabetic rats. Each rat in the three L-carnitine-treated groups was injected subcutaneously with L-carnitine, 50 (D50), 100 (D100), or 200 (D200) mg/kg body weight every other day for four weeks, and animals in normal (N) and diabetic (DM) groups received saline by the same method. Diabetic rats had significantly lower carnitine concentrations in serum and liver compared with normal rats. Total carnitine concentrations were increased dose-dependently by carnitine treatment. Total IGF-I in serum from diabetic rats was increased dose-dependently by carnitine treatment, but was statistically significant only in the D200 group. The expression of liver IGF-I mRNA was lower in diabetic rats than in normal rats and increased by L-carnitine treatment. L-Carnitine treatment of diabetic rats had no effect on the levels of IGF-II in serum, liver, and kidney. Although the levels of IGF-II in serum and kidney of diabetic rats were increased in comparison with normal rats, IGF-II mRNA was not expressed in liver. Diabetic rats had markedly lower IGFBP-3 than normal rats did, and IGFBP-3 was increased by L-carnitine treatment. These results demonstrate that L-carnitine treatment of diabetic rats modulates the IGFs/IGFBPs axis. Especially note-worthy is that L-carnitine at a dose of 200 mg/kg/48 h for four weeks was able to restore serum total IGF-I in STZ-induced diabetic rats to nearly normal levels.     

Hypoglycemic effect of Rehmannie Radix Preparata (Sookjihwang) extract in streptozotocin-induced diabetic rats

Rhemannie Radix Preparata (RRP) has been previously employed in traditional oriental medicine as a treatment for diabetic thirst and improving blood flow. The aim of this study was to evaluate its hypoglycemic control by assaying the activities of key enzymes of carbohydrate metabolism in streptozotocin-(STZ)-induced diabetic rats. Further, RRP extracts were prepared in water (RRPW), in 50% ethanol (RRP50), and in 100% ethanol (RRP100), respectively, and compared for their actions in diabetic rats. The oral treatment of RRP (5 mg/kg b.w./d) to diabetic rats for 21 days resulted in a significant decline in blood glucose by 67% compared to diabetic control rats (P < 0.05). The altered activities of glucokinase, glucose-6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6PGD), and acetyl CoA carboxylase (ACC) in the livers of diabetic rats were reversed significantly to near-normal levels by the administration of RRP (P < 0.05). Among the three RRP extracts, RRP100 was the most effective in terms of hypoglycemic action. However, the administration of RRP to diabetic rats did not improve insulin production. The modulatory effects of RRP100 on the attenuation of carbohydrate enzyme activities appear to hold promise for widespread use for the treatment of diabetes in the future.     

Anti-Osteoporotic Effects of Angelica sinensis (Oliv.) Diels Extract on Ovariectomized Rats and Its Oral Toxicity in Rats

Angelica sinensis root is one of the herbs most commonly used in China; it is also often included in dietary supplements for menopause in Europe and North America. In the present study, we examined the anti-osteoporotic effects of A. sinensis extract in an ovariectomized (OVX) rat model of osteoporosis as well as toxicity of the extract after repeated oral administration. The OVX rats were treated with 17β-estradiol (10 μg/kg i.p. once daily) or A. sinensis extract (30, 100, and 300 mg/kg, p.o. once daily) for four weeks. The bone (femur) mineral density (BMD) of rats treated with the extract (300 mg/kg) was significantly higher than that of the OVX-control, reaching BMD of the estradiol group. Markers of bone turnover in osteoporosis, serum alkaline phosphatase, collagen type I C-telopeptide and osteocalcin, were significantly decreased in the extract group. The body and uterus weight and serum estradiol concentration were not affected, and no treatment-related toxicity was observed during extract administration in rats. The results obtained indicate that A. sinensis extract can prevent the OVX-induced bone loss in rats via estrogen-independent mechanism.     

Opuntia humifusa stems lower blood glucose and cholesterol levels in streptozotocin-induced diabetic rats

The Opuntia humifusa stem (OHSt) contains high levels of antioxidants including vitamin C, flavonoids, and polyphenols that may prove beneficial in treating diabetes mellitus. The objective of this study was to examine the hypothesis that intake of the OHSt regulates blood glucose levels and hypolipidemic responses in rats with diabetes mellitus induced by injection of streptozotocin. Forty Sprague-Dawley rats (6 weeks of age) were assigned to 5 groups: normal control, rats with streptozotocin-induced diabetes mellitus (DM), DM treated with OHSt 150 mg/kg per day, DM treated with OHSt 250 mg/kg per day, and DM treated with OHSt 500 mg/kg per day. Powdered OHSt was suspended in distilled water and administered orally through the sonde once daily. After 7 weeks of treatment, the fasting blood glucose and triglyceride levels of the OHSt groups were significantly lower when compared with the DM group (P < .05). Treatment with the OHSt also resulted in a significant decrease in serum total cholesterol and low-density lipoprotein cholesterol (P < .05). Decreases in both total cholesterol and low-density lipoprotein cholesterol were accompanied by a significant increase in serum high-density lipoprotein cholesterol (P < .05). Furthermore, levels of alanine aminotransferase and aspartate aminotransferase were significantly lower in the OHSt groups than in the DM group (P < .05). In addition, a significant increase in relative beta cell volume of pancreas was observed in rats treated with 500 mg/kg of OHSt when compared with the untreated DM rats (P < .05). The overall results suggest that the OHSt possesses potential hypoglycemic and hypolipidemic activity in streptozotocin-induced diabetic rats.     

Can methanolic extract of Nigella sativa seed affect glyco-regulatory enzymes in experimental hepatocellular carcinoma?

Background and aim

To investigate the possible modulating role of “Nigella sativa” (NS), a plant commonly used in Egyptian traditional medicine, on premalignant perturbations in three glycol-regulatory enzymes in an experimental rat model of hepatocellular carcinoma (HCC).

Methods

Thirty-six (36) male albino rats were divided into four groups (n = 9). Group 1 served as a normal control, group 2 was treated with methanolic extract of Nigella sativa (MENS) (1 g/kg/day, orally) for 14 weeks, group 3 received a single intraperitoneal dose of diethyl nitrosamine (DENA) (200 mg/kg), followed 2 weeks later by a subcutaneous injection of carbon tetrachloride (CCl₄, 3 ml/kg/week/6 weeks) and group IV was treated with MENS for 2 weeks prior to administration of the carcinogenic combination (DENA + CCl₄, as in group 3) until the end of the experiment. The total period of the experiment was 14 weeks.

Results

In the DENA + CCl₄-treated group, there was a significant increase in the relative liver weight, serum alpha fetoprotein level and the activities of hexokinase, glyceraldehyde phosphate dehydrogenase and glucose 6 phosphate dehydrogenase in both the serum and liver homogenate; this was accompanied by a subsequent decrease in body weight. Pre-treatment with MENS significantly maintained these parameters close to the normal condition.

Conclusion

Based on these results, we conclude that MENS has a chemo-preventive effect against the progression into liver malignancy through its modulation of the energy metabolic pathways (i.e. glycolysis) that may be involved in hepatocarcinogenesis.     

Hypoglycemic and antioxidant effects of Daraesoon (Actinidia arguta shoot) in animal models of diabetes mellitus

BACKGROUND/OBJECTIVES

The primary objective of the treatment of diabetes mellitus is the attainment of glycemic control. Hyperglycemia increases oxidative stress which contributes to the progression of diabetic complications. Thus, the purpose of this study was to investigate the hypoglycemic and antioxidant effects of Daraesoon (Actinidia arguta shoot) in animal models of diabetes mellitus.

MATERIALS/METHODS

Rats with streptozotocin-induced diabetes received an oral administration of a starch solution (1 g/kg) either with or without a 70% ethanol extract of Daraesoon (400 mg/kg) or acarbose (40 mg/kg) after an overnight fast and their postprandial blood glucose levels were measured. Five-week-old C57BL/6J mice were fed either a basal or high-fat/high-sucrose (HFHS) diet with or without Daraesoon extract (0.4%) or acarbose (0.04%) for 12 weeks after 1 week of adaptation to determine the effects of the chronic consumption of Daraesoon on fasting hyperglycemia and antioxidant status.

RESULTS

Compared to the control group, rats that received Daraesoon extract (400 mg/kg) or acarbose (40 mg/kg) exhibited a significant reduction in the area under the postprandial glucose response curve after the oral ingestion of starch. Additionally, the long-term consumption of Daraesoon extract or acarbose significantly decreased serum glucose and insulin levels as well as small intestinal maltase activity in HFHS-fed mice. Furthermore, the consumption of Daraesoon extract significantly reduced thiobarbituric acid reactive substances and increased glutathione levels in the livers of HFHS-fed mice compared to HFHS-fed mice that did not ingest Daraesoon.

CONCLUSIONS

Daraesoon effectively suppressed postprandial hyperglycemia via the inhibition of α-glucosidase in STZ-induced diabetic rats. Chronic consumption of Daraesoon alleviated fasting hyperglycemia and oxidative stress in mice fed a HFHS diet.     

Prophylactic effect of aqueous extract of Sesamum indicum seeds on ethanol-induced toxicity in male rats

The liver is vulnerable to alcohol-related injury because it is the primary site of alcohol metabolism. Additionally, a number of potentially dangerous by-products are generated as alcohol is broken down in the liver. However, dietary supplements may prevent or relieve some of alcohol''s deleterious effects. Therefore, this study was conducted to evaluate the prophylactic effect of aqueous extract of Sesamum indicum (SI) on ethanol induced toxicity in rats. Male Wistar albino rats were divided into control, ethanol, pre-treatment, simultaneous and post-treatment groups. In the prophylactic experiment, Sesamum indicum, (200 mg/kg body weight) was administered by oral gavage for 28 days; two hours before, simultaneously with or two hours after ethanol exposure. Toxicity was induced by administering 45% ethanol (4.8 g/kg bw) by oral gavage. Lipid peroxidation (TBARS) and reduced glutathione (GSH) levels and catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD) and gluthathione-S-transferase (GST) activities were then determined in the liver, serum triglyceride (TG) levels, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were monitored and histological examination was carried out. The results revealed that ethanol administration led to significant elevation of TBARS level while depleting in the level of GSH as well as CAT, GPx, SOD and GST activities. Similarly, TG level and ALT and AST activities were elevated. The SI pre-treated group significantly inhibited TBARS, restored GSH level, enhanced CAT, GPx, SOD and GST activities and significantly decreased the elevated level of serum TG, ALT and AST activities. SI treatment (simultaneously with ethanol) exhibited similar effects to those of the SI pre-treated groups, while the SI post-treated group did not show the same protection as the Pre-treated group. S. indicum possesses antioxidant and hepatoprotective properties, that eliminate the deleterious effects of toxic metabolites of ethanol.     

Marginal nutritional status of zinc, iron, and calcium increases cadmium retention in the duodenum and other organs of rats fed rice-based diets

Dietary minerals Zn, Fe, and Ca are antagonistic to Cd absorption. We showed earlier that rats fed a rice-based diet with a marginal content of these nutrients absorbed more Cd than rats fed adequate Zn-Fe-Ca (Environ. Sci. Technol., 36 (2002) 2684-2692). The present experiment was designed to determine the effects of marginal dietary Zn, Fe, and Ca on the uptake and turnover of Cd in the gastrointestinal tract. Two groups of weanling female rats (six per treatment) were fed a diet containing 40% cooked, dried rice containing 0.6 mg Cd/kg. The diet of one group contained adequate Zn (35 mg/kg), Fe (30 mg/kg), and Ca (5000 mg/kg), while that of the other group contained marginal Zn (6 mg/kg), Fe (9 mg/kg), and Ca (2500 mg/kg). Rats were fed for 5 weeks and then orally dosed with 1g of diet containing rice extrinsically labeled with 109Cd. From 0.25 to 64 days after dosing, 109Cd and total Cd concentrations were determined in intestinal segments. Shortly after dosing, 109Cd, as a percentage of the dose, was about 4 times higher in the duodenum of marginally fed rats than in that of control rats (10% vs 40%, respectively). Sixty-four days after dosing, 109Cd was 10 times higher in marginally fed rats than in controls; however, of the amount at day 1, <0.1% remained at day 64. After 5 weeks, the concentration of elemental Cd in the duodenum of the marginally fed rats was 8 times higher than that of control rats (24 microg/g dry wt. vs 2.9 microg/g dry wt., respectively). Cd concentrations in liver and kidney were 5 times higher in the marginally fed rats than those in controls (liver, 0.81 microg/g dry wt. vs 0.14 microg/g dry wt.; kidney, 4.7 microg/g dry wt. vs 0.92 microg/g dry wt., respectively). These data suggest that marginal intakes of Zn, Fe, and Ca cause the accumulation of Cd in the duodenum, which results in a greater rate of Cd absorption and a greater accumulation in the internal organs. Results are discussed in relation to mineral nutrient status and risk assessment of Cd in natural food sources.     

Antidiabetic and enzymatic antioxidant properties from methanol extract of Ficus talboti bark on diabetic rats induced by streptozotocin

ObjectiveTo explore scientifically, the type–I anti-diabetic potential of Ficus talboti bark (FTB).MethodsThe HPLC analysis was carried out to identify the phenolic compounds. Effect of two doses of methanol extract of FTB (100 mg/kg and 200 mg/kg body wt.) was orally administered to STZ (Streptozotocin) induced diabetic rats for 21 days. The various parameters were studied including body weight, fasting blood glucose levels, plasma insulin, lipid profile, glycogen content, total protein, serum enzymes levels, and antioxidant activities in normal, treated and diabetic rats. Histochemical analysis of liver and pancreas were also carried out in normal, treated and diabetic rats.ResultsThe HPLC analysis showed the presence of antidiabetic responsible compounds of Rutin, Quercetin and Kaemfeorl. The treatment group with the extract at two dose levels showed a significant increase in the liver, muscle glycogen and serum insulin level and a significant decrease in fasting blood glucose and serum marker enzyme levels. The total cholesterol and serum triglycerides levels were also significantly reduced and the high density lipoprotein and plasma enzymes level was significantly increased upon treatment with the FTB methanol extract. Histochemical study of pancreas also confirmed the biochemical findings. Acute toxicity studies revealed the non-toxic nature of the FTB methanol extract.ConclusionThe results of the experiments presented here suggest that methanol extract of FTB exerts significant antidiabetic and antioxidant effect in STZ induced diabetic rats.     

Dietary soy isoflavones increase insulin secretion and prevent the development of diabetic cataracts in streptozotocin-induced diabetic rats

Soy isoflavone–containing diets have been reported to be beneficial in diabetes. This present study investigated the hypoglycemic effects of isoflavones in streptozotocin (STZ)-induced diabetes. Diabetes was induced in male Sprague-Dawley rats by intraperitoneal injection of 100 mg/kg STZ. Diabetic rats were then randomly divided into 3 groups and received a special diet supplemented with casein (control), low-isoflavone soy (LIS) protein, and high-isoflavone soy protein (HIS) for 8 weeks. Compared with the control or LIS groups, those rats on the HIS diet had significantly increased body weight and serum insulin levels and reduced serum glucose and methylglyoxal levels. Serum glutathione levels were also increased in rats given the HIS diet compared with those in the control or LIS (P < .01). Serum high-density lipoprotein cholesterol level was significantly higher in HIS-fed rats than that of the control or LIS rats (P < .05). More importantly, the death rate and incidence of cataracts in the diabetic rats were markedly decreased in the HIS group. In conclusion, ingestion of high-isoflavone soy protein not only lowers glucose levels but also reduces the incidence of cataracts in diabetic rats. The beneficial effects of soy isoflavones are attributed to increased insulin secretion, a better glycemic control, and antioxidant protection.