Effect of Combined Leaf Extracts of Vernonia amygdalina (Bitter Leaf) and Gongronema latifolium (Utazi) on the Pancreatic beta-Cells of Streptozotocin- Induced Diabetic Rats

The study evaluated the effect of combined extracts of Vernonia amygdalina (VA) and Gongronema latifolium (GL) on the pancreas of streptozotocin (STZ) induced diabetic Wistar rats. Thirty-two (32) albino rats were divided equally into 4 groups. Groups A and B which served as normal (NC) and diabetic (DC) controls respectively, received placebo treatment. The diabetic test groups C and D were respectively treated with combined extracts of VA and GL (200mg/kg b. w., p. o.) and insulin, (humulin 5 IU/kg, s.c.) for 28 days. Thereafter, the animals were sacrificed and blood and pancreas were collected for serum glucose and histological evaluation, respectively. Changes in animal weight were also measured within the period. From the results it was revealed that both the combined extracts and humulin significantly increased the animals’ body weight (p<0.05) from -10.5% reduction in the DC, to 7.6% and 8.9% respectively. In the same order, serum glucose significantly decreased (p<0.05) by 12.49% and 14.96% after the 28-day treatment compared to DC. The extent of reversal of hyperglycemia in the extract treated animals compared well with the insulin treated group. The biochemical results were corroborated with results of histological evaluations: The pancreatic β-cells of DC animals which were distorted and degenerated with shrunken cell mass as against prominent islet cells with normal exocrine pancreas of NC animals became rapidly proliferated upon intervention with the combined extracts, suggesting a possible regeneration of the islet cells. On the otherhand, intervention with humulin did not produce observable differences in the cyto-architecture of the pancreatic islets compared to the diabetic control, confirming an extra-pancreatic mechanism of insulin

Effect of traditional diets on oxidative stress and lipid profile of alloxan induced diabetic rats

The objective of this study was to compare the effect of recommended diet namely, plantain porridge and beans with other traditional Nigerian diets on oxidative stress and lipid profile in alloxan diabetic rats. Therefore, in the design, six groups (1 non diabetic and 5 diabetic) of 7 rats each, were accordingly treated: the normal and diabetic controls were fed normal rat pellets; garri with afang soup, pounded yam with edikang ikong soup, ekpang nkukwo, and the control diet (plantain porridge with beans) respectively, were fed to the other diabetic groups. The diets and water were given ad libitium and this lasted for 15 days after which biochemical indices of oxidative stress and lipid profile were respectively determined in liver homogenates and serum of the experimental animals. Superoxide dismutase (SOD) activity significantly increased (p&lt;0.05) in all diet fed rats relative to the diabetic control. Although the increase was highest in the control diet, it was not significant (p&gt;0.05) with respect to the traditional diets. The reverse was the case with Glutathione peroxidase (GPx) activity, which was significantly decreased in the control diet compared to the traditional diets and diabetic control. Yet the extent of lipid peroxidation (malondialdehyde, MDA) was seen to be highest in the control diet. The effects of the traditional diets and the control diet on lipid profile were similar. These traditional diets could be more effective in amelioration of oxidative stress in dietary management of diabetes mellitus

Bioactivity-Guided Isolation of Ethyl-p-methoxycinnamate, an Anti-inflammatory Constituent, from Kaempferia galanga L. Extracts

molecule

A Soxhlet Extract of Gongronema latifolium Retains Moderate Blood Glucose Lowering Effect and Produces Structural Recovery in the Pancreas of STZ-Induced Diabetic Rats

Background: Gongronema latifolium Benth. (GL) possesses considerable glucose lowering effects able to be utilized on a large-scale. This paper investigates the effects of a Soxhlet extract on hyperglycemia, Langerhans islets and glucose uptake by abdominal muscles. Methods: Ethanol and a Soxhlet apparatus were used to obtain GL ethanolic Soxhlet extract (GLES). It was then administered to randomly-segregated male Sprague-Dawley, normal and STZ-induced diabetic rats, using oral gavage to evaluate blood glucose levels (BGLs), serum lipid profile, insulin levels and the pancreas post-treatment. Results: GLES significantly (p &lt; 0.05) decreased BGLs of normal rats in glucose tolerance testing at a dose of 2 g/kg b.w. but failed to do so in diabetic rats undergoing acute 7-h treatment. Given twice-daily, 1 g/kg b.w. of GLES moderately controlled diabetic BGLs starting from day 10. After 14 days of treatment, 1 g/kg and 0.5 g/kg b.w. of GLES caused 44% and 50% respective increases in the average area of Langerhans islets compared to DC. Using isolated rat abdominal muscle, GLES was found to be a mild insulin-sensitizer. GC-MS analysis revealed the presence of the known glucose-lowering phytosterol, Sitostenone. Conclusion: Despite retaining moderate antidiabetic activity, Soxhlet extraction of Gongronema latifolium probably leads to the destruction of active heat-liable compounds

African Walnuts (Tetracarpidium conophorum) Modulate Hepatic Lipid Accumulation in Obesity via Reciprocal Actions on HMG-CoA Reductase and Paraoxonase.

BACKGROUND Obesity is characterized by increased body fat and involves an imbalance between the synthesis and degradation of lipids. OBJECTIVE The study aimed to investigate the effect of African walnuts (Tetracarpidium conophorum) on lipids storage and the regulatory enzymes of hepatic lipid metabolism in obese rats. METHODS Nuts were extracted in ethanol (WE) and further separated to obtain the ethyl-acetate fraction (ET) and the residue (RES). These were administered orally to 3 groups of monosodium glutamate- obese rats (n = 6), respectively, for 6 weeks. Other groups in the study were: normal (NC), obese control (OC) and standard control (SC) which received orlistat. Hepatic total lipids, total phospholipids, triacylglycerol (TG), total cholesterol (TCHOL), 3-hydroxyl-3-methylglutaryl-CoA (HMG-CoA) reductase and paraoxonase were studied. RESULTS Total lipids, TG and TCHOL which increased in OC compared to NC group, decreased. HMG-CoA reductase activity decreased in the 3 study groups relative to OC. Paraoxonase activity which decreased in OC was up-regulated, while the magnitude of hepatic cholesterol decreased from 94.32 % in OC to 52.19, 65.43 and 47.04 % with WE, ET and RES, respectively. Flavonoids, alkaloids, glycosides, tannins and saponins were detected in the nut. GC-MS analysis revealed 16, 18 and 10 volatile components in WE, ET and RES, respectively. Unsaturated fatty acids (linolenic acids: 33.33, 47.95 and 50.93 %, and α-linolenic acids: 25, 19.66 and 26.63 %) in WE, ET and RES, respectively, are the most abundant, and likely to be responsible for the observed activity. CONCLUSION African walnuts can prevent hepatic lipid accumulation through reciprocal actions on HMG-CoA reductase and paraoxonase in obesity

African Walnuts (Tetracarpidium conophorum) Modulate Hepatic Lipid Accumulation in Obesity via Reciprocal Actions on HMG-CoA Reductase and Paraoxonase.

BACKGROUND Obesity is characterized by increased body fat and involves an imbalance between the synthesis and degradation of lipids. OBJECTIVE The study aimed to investigate the effect of African walnuts (Tetracarpidium conophorum) on lipids storage and the regulatory enzymes of hepatic lipid metabolism in obese rats. METHODS Nuts were extracted in ethanol (WE) and further separated to obtain the ethyl-acetate fraction (ET) and the residue (RES). These were administered orally to 3 groups of monosodium glutamate- obese rats (n = 6), respectively, for 6 weeks. Other groups in the study were: normal (NC), obese control (OC) and standard control (SC) which received orlistat. Hepatic total lipids, total phospholipids, triacylglycerol (TG), total cholesterol (TCHOL), 3-hydroxyl-3-methylglutaryl-CoA (HMG-CoA) reductase and paraoxonase were studied. RESULTS Total lipids, TG and TCHOL which increased in OC compared to NC group, decreased. HMG-CoA reductase activity decreased in the 3 study groups relative to OC. Paraoxonase activity which decreased in OC was up-regulated, while the magnitude of hepatic cholesterol decreased from 94.32 % in OC to 52.19, 65.43 and 47.04 % with WE, ET and RES, respectively. Flavonoids, alkaloids, glycosides, tannins and saponins were detected in the nut. GC-MS analysis revealed 16, 18 and 10 volatile components in WE, ET and RES, respectively. Unsaturated fatty acids (linolenic acids: 33.33, 47.95 and 50.93 %, and α-linolenic acids: 25, 19.66 and 26.63 %) in WE, ET and RES, respectively, are the most abundant, and likely to be responsible for the observed activity. CONCLUSION African walnuts can prevent hepatic lipid accumulation through reciprocal actions on HMG-CoA reductase and paraoxonase in obesity

Bioassay-Guided Antidiabetic Study of &lt;em&gt;Phaleria macrocarpa&lt;/em&gt; Fruit Extract

An earlier anti-hyperglycemic study with serial crude extracts of &lt;em&gt;Phaleria macrocarpa&lt;/em&gt; (PM) fruit indicated methanol extract (ME) as the most effective. In the present investigation, the methanol extract was further fractionated to obtain chloroform (CF), ethyl acetate (EAF), &lt;em&gt;n&lt;/em&gt;-butanol (NBF) and aqueous (AF) fractions, which were tested for antidiabetic activity. The NBF reduced blood glucose (&lt;em&gt;p&lt;/em&gt; &lt; 0.05) 15 min after administration, in an intraperitoneal glucose tolerance test (IPGTT) similar to metformin. Moreover, it lowered blood glucose in diabetic rats by 66.67% (&lt;em&gt;p&lt;/em&gt;&lt;em&gt; &lt;/em&gt;&lt; 0.05), similar to metformin (51.11%), glibenclamide (66.67%) and insulin (71.43%) after a 12-day treatment, hence considered to be the most active fraction. Further fractionation of NBF yielded sub-fractions I (SFI) and II (SFII), and only SFI lowered blood glucose (&lt;em&gt;p &lt;/em&gt;&lt; 0.05), in IPGTT similar to glibenclamide. The ME, NBF, and SFI correspondingly lowered plasma insulin (&lt;em&gt;p &lt;/em&gt;&lt; 0.05) and dose-dependently inhibited glucose transport across isolated rat jejunum implying an extra-pancreatic mechanism. Phytochemical screening showed the presence of flavonoids, terpenes and tannins, in ME, NBF and SFI, and LC-MS analyses revealed 9.52%, 33.30% and 22.50% mangiferin respectively. PM fruit possesses anti-hyperglycemic effect, exerted probably through extra-pancreatic action. Magniferin, contained therein may be responsible for this reported activity