In vitro toxicity and antidiabetic activity of a newly developed polyherbal formulation (MAC-ST/001) in streptozotocin-induced diabetic Wistar rats

The present study was designed to investigate the hypoglycemic effect of an aqueous extract of MAC-ST/001 (a new polyherbal formulation) which was given once daily to rats at different doses. The animals were divided into diabetic and nondiabetic control groups. The duration of each experiment lasted from 1 week to 1 month, and the results were compared with that of the standard hypoglycemic drug glibenclamide (10 mg/kg), which was given once daily. In this study, biochemical and histopathological parameters were studied in streptozotacin (STZ) (single intraperitoneal injection of 55 mg/kg)-induced diabetic rats. The diabetic rats showed a significant (p?<?0.05 and p?<?0.01) decrease in their body weight and serum amylase with marked elevation in blood glucose, serum cholesterol, blood urea nitrogen, creatinine, alkaline phosphatase, and serum transaminases (AST and ALT) after 1 week till the 28th day of diabetes. Cytotoxicity of MAC-ST/001 formulation was also studied on C2C12, 3T3-L1, and HepG2 cells through MTT assay. Histological examination of the liver and pancreas of normal control, diabetic control, and drug-treated rats revealed significant results. Finally, it was concluded that administration of this MAC-ST/001 extract reversed most blood and tissue changes caused by STZ-induced diabetes in rats.     

Therapeutic Potential of Some Plant Extracts Used in Turkish Traditional Medicine on Streptozocin-Induced Type 1 Diabetes Mellitus in Rats

Diabetes mellitus (DM) is known to impair many physiological functions. Some reports claim that medicinal plants can reduce these alterations caused by DM. The aim of this study was to investigate the therapeutic potential of aqueous-methanol extracts of Urtica dioica, Thymus vulgaris (TV), Myrtus communis (MC), Scolymus hispanicus (SH) and Cinnamomun zeylanicum (CZ) on streptozotocin (STZ)-induced type 1 DM in rats. Diabetes was induced via a single i.p. injection of STZ (65 mg/kg body weight). After 1 week to allow for development of diabetes, each plant extract was administered to diabetic rats separately at a dose of 100 mg/kg body weight daily for 28 days. The results showed that only SH extract significantly (P < 0.05) amended fasting blood glucose level. The lipid profile was ameliorated especially by supplementations of TV, MC and CZ extracts. Almost all plant extract treatments markedly (P < 0.05) increased reduced glutathione content and decreased lipid peroxidation levels of erythrocyte, plasma, retina and lens tissues. They also significantly (P < 0.05) amended erythrocyte catalase activity, levels of marker serum enzymes (except amylase), urea and blood urea nitrogen when compared to diabetic rats treated with nothing. Furthermore, none of the plant extracts counteracted body weight loss of diabetic rats. Our data revealed that the aforementioned plant extracts have remarkable potential to counteract DM-caused alterations, probably through their antioxidant and free radical-defusing effects.     

Cistanches Herba aqueous extract affecting serum BGP and TRAP and bone marrow Smad1 mRNA, Smad5 mRNA, TGF-β1 mRNA and TIEG1 mRNA expression levels in osteoporosis disease

We studied molecular mechanism of Cistanches Herba aqueous extract (CHAE) in ovariectomized (OVX) rats, as an experimental model of postmenopausal osteoporosis. Female rats were either sham-operated or bilaterally OVX; and at 60 days postoperatively. The OVX group (n = 8) received an ovariectomy and treatment with normal saline for 90 days commencing from 20th post ovariectomy day. The ovariectomized +CHAE (OVX + CHAE) group (n = 8) received an ovariectomy and were treated with Cistanches Herba aqueous extract of 100 mg/kg body weight daily for 90 days commencing from 22nd post ovariectomy day. The ovariectomy +CHAE (OVX + CHAE) group (n = 8) received an ovariectomy, and were treated with the of 200 mg/kg body weight daily for 90 days commencing from 20th post ovariectomy day. Serum BGP and TRAP, E2, FSH and LH level, bone marrow Smad1, Smad5, TGF-β1 and TIEG1 mRNA expression levels were examined. Results showed that serum BGP and TRAP, FSH and LH levels were significantly increased, whereas E2, Smad1, Smad5, TGF-β1 and TIEG1 mRNA and proteins expression levels were significantly decreased in OVX rats compared to sham rats. 90 days of CHAE treatment could significantly decrease serum BGP and TRAP, FSH and LH levels, and increase E2, Smad1, Smad5, TGF-β1 and TIEG1 mRNA and proteins expression levels in OVX rats. It can be concluded that CHAE play its protective effect against OVX-induced bone degeneration partly by regulating some bone metabolism related genes, e.g. Smad1, Smad5, TGF-β1 and TIEG1.     

Spirulina: possible pharmacological evaluation for insulin-like protein

Diabetes mellitus is a metabolic disorder characterized by hyperglycemia, hyperlipidemia, hyperaminoacidemia, and hypoinsulinemia that leads to reduction in both insulin secretion and insulin action. Several natural products have been isolated and identified to restore the complications of diabetes. Spirulina is a naturally occurring freshwater cyanobacterium, enriched with proteins and essential nutrients. Treatment of diabetic rats with crude, aqueous extract, ethanolic extract, and insulin-like protein of Spirulina successfully ameliorated diabetic complications by increasing body weight and significantly decreasing the levels of blood glucose, glycosylated hemoglobin, serum glutamic oxaloacetic transaminase, serum glutamic pyruvic transaminase, alkaline phosphatase, total bilirubin, serum creatinine, serum uric acid, and blood urea nitrogen (p?<?0.0001). Comparatively, the crude extract and insulin-like protein were found to be more effective than the aqueous and ethanolic extracts.     

Viscum album prevents haematological changes,electrolyte imbalance,changes in liver function enzymes and histological alterations in some selected tissues in cadmium chloride-intoxicated rats

BackgroundThe use of Viscum album to treat different diseases is popular in the practise of alternative medicine. We investigated the ability of the aqueous extract of V. album to protect against the toxic effects of cadmium.MethodsThirty rats used for the experiment were treated as follows; Group 1 – no cadmium or extract. Group 2–10 mg/kg body weight of cadmium chloride. Group 3–10 mg/kg body weight of cadmium chloride and 200 mg/kg body weight of aqueous extract of V. album. Group 4–10 mg/kg body weight of cadmium chloride and 400 mg/kg body weight of aqueous extract of V. album. Group 5–10 mg/kg body weight of cadmium chloride with 800 mg/kg body weight of aqueous extract of V. album. Group 6–10 mg/kg body weight of cadmium chloride and atorvastatin (100 mg/kg body weight).ResultsApart from WBC and platelets, other haematological parameters and electrolytes, urea and creatinine levels were not significantly affected by the administration of cadmium chloride along with the aqueous extract of V. album. Treatment with the extract caused significant decreases in the hepatosomatic index, cardiosomatic index, and increase in renosomatic index of the test rats. It also resulted in significant (P < 0.05) decrease in AST level. Histological report also shows that treatment with the extract restored the normal myocardium and vascular architecture of the heart, normal portal and vascular architecture of the liver and normal glomerular and tubular architecture of the kidney, in the cadmium-intoxicated experimental rats.ConclusionV. album protects against the toxic effects of cadmium chloride.     

Change in histone H3 phosphorylation,MAP kinase p38, SIR 2 and p53 expression by resveratrol in preventing streptozotocin induced type I diabetic nephropathy

Resveratrol has been reported to have a wide variety of biological effects. However, little is known regarding its role on phosphorylation of histone H3, MAP kinase p38, SIR2 and p53 in type I diabetic nephropathy (DN). Hence, the present study was undertaken to examine changes in the above said parameters by resveratrol treatment. Male Sprague-Dawley rats were rendered diabetic using a single dose of streptozotocin (55 mg/kg, i.p.). DN was assessed by measurements of blood urea nitrogen and creatinine levels. Phosphorylation of histone H3, SIR2, p53 and MAP kinase p38 expression were examined by western blotting. This study reports that treatment of resveratrol prevents the decrease in the expression of SIR2 in diabetic kidney. It also prevents increase in p38, p53 expression and dephosphorylation of histone H3 in diabetic kidney. This is the first report which suggests that protection against development of diabetic nephropathy by resveratrol treatment involves change in phosphorylation of histone H3, expression of Sir-2, p53 and p38 in diabetic kidney.     

Renoprotective effects of berberine and its possible molecular mechanisms in combination of high-fat diet and low-dose streptozotocin-induced diabetic rats

Berberine (BBR), an effective compound of Chinese traditional herbal medicine, has preventive effects on diabetes and its complications. In this study, we investigated the therapeutic effects and underlying molecular mechanisms of BBR in rats with high-fat diet and streptozotocin (STZ)-induced diabetic nephropathy model. BBR (50, 100, 200 mg/kg/d) were orally administered to male Sprague–Dawley rats after STZ injection and conducted for 8 weeks. Renal damage was evaluated by kidney weight to body weight ratio (KW/BW), urine microalbumin (UMAlb), urine protein for 24 h (UP24 h), urine creatinine (UCr), and histological examination. Type IV collagen and transforming growth factor-beta1 (TGF-β₁) were detected by immunohistochemistry and ultrastructure of glomeruli was observed. Fasting blood glucose (FBG),serum creatinine (SCr), blood urea nitrogen (BUN), total cholesterol (TC), triglyceride (TG), high-density lipoprotein-cholesterol (HDL-c), low-density lipoprotein-cholesterol (LDL-c) in serum and G protein-coupled receptor kinases (GRKs), cAMP in kidney were measured. Remarkable renal damage, hyperglycemia and hyperlipidemia were observed in DN rats. BBR could restore renal functional parameters, suppress alterations in histological and ultrastructural changes in the kidney tissues, improve glucose and lipid metabolism disorders, and increase cAMP levels compared with those of DN model group. Furthermore, BBR down-regulated total protein expression of GRK2, GRK3 and up-regulated expression of GRK6 of renal cortex in DN rats, but had a slight effects on GRK4 and GRK5. These studies demonstrate, for the first time, that BBR exerts renoprotection in high-fat diet and STZ-induced DN rats by modulating the proteins expression of GRKs in G protein- AC-cAMP signaling pathway.     

Antioxidant and hepatoprotective potential of Pouteria campechiana on acetaminophen-induced hepatic toxicity in rats

Pouteria campechiana (Kunth) Baehni. is used as a remedy for coronary trouble, liver disorders, epilepsy, skin disease, and ulcer. Therefore, the present study aims to investigate the antioxidant and hepatoprotective effect of polyphenolic-rich P. campechiana fruit extract against acetaminophen-intoxicated rats. Total phenolic and flavonoid contents of egg fruit were estimated followed by the determination of antioxidant activities. Treatment with P. campechiana fruit extract effectively scavenged the free radicals in a concentration-dependent manner within the range of the given concentrations in all antioxidant models. The presence of polyphenolic compounds were confirmed by high-performance thin-layer chromatography (HPTLC). The animals were treated with acetaminophen (250 mg/kg body weight; p.o.) thrice at the interval of every 5 days after the administration of P. campechiana aqueous extract and silymarin (50 mg/kg). Acetaminophen treatment was found to trigger an oxidative stress in liver, leading to an increase of serum marker enzymes. However, treatment with P. campechiana fruit extract significantly reduced the elevated liver marker enzymes (aspartate transaminase, alanine transaminase, and alkaline phosphatase) and increased the antioxidant enzymes (viz., superoxide dismutase and catalase) and glutathione indicating the effect of the extract in restoring the normal functional ability of hepatocytes. These results strongly suggest that P. campechiana fruit extract has strong antioxidant and significant hepatoprotective effect against acetaminophen-induced hepatotoxicity.     

Nephroprotective effect of pigmented violacein isolated from Chromobacterium violaceum in wistar rats

The present study aimed to analyze the nephroprotective property of violacein obtained from the bacterium, Chromobacterium violaceum. The nephrotoxicity in the animal model was induced by gentamicin, potassium dichromate, mercuric chloride, and cadmium chloride-induced nephrotoxicity in the Wistar rats was analyzed by measuring the serum creatinine, uric acid, and urea level. The present investigation revealed the nephroprotective property on convoluted proximal tubule (S1 and S2 segments) and the straight proximal tubule (S3 segment). Also, violacein significantly improved the renal function by the renal protective property on S2 segment of proximal tubule from the nephrotoxicity stimulated by mercuric chloride, potassium dichromate, cadmium chloride and gentamicin in animal models. Animal model studies revealed that violacein at 20 and 40 mg/kg p.o improved the renal function and significantly reduced the increased amount of uric acid, creatinine, and blood urea compared to the control.     

Biomarkers of Lead Exposure Among a Population Under Environmental Stress

This study aimed to evaluate the relationship between blood lead and serum creatinine and blood lead and serum urea nitrogen levels as biomarkers of lead exposure from subjects living in a historic polymetallic mining area in China. Elevated levels were found for blood lead, serum creatinine, and serum urea nitrogen in the mining area with mean values at 245.65 μg/l, 74.16 μmol/l, and 12.79 mmol/l, which were significantly higher than those in the control area, respectively. Moreover, the coefficients between paired results for blood lead and serum creatinine and blood lead and serum urea nitrogen were positively statistically significant (serum creatinine vs. blood lead, r?=?0.35, p?<?0.05; serum urea nitrogen vs. blood lead, r?=?0.48, p?<?0.05). With respect to the effects of sex and age on the blood lead, serum creatinine, and serum urea nitrogen levels, data analysis revealed there was a tendency for higher blood lead, serum creatinine, and serum urea nitrogen levels in females than in males, and the levels of blood lead, serum creatinine, and serum urea nitrogen increased among older residents. We conclude that females and the older population in the mining area are more susceptible to lead exposure. Blood lead, serum creatinine, and serum urea nitrogen can be useful biomarkers of lead exposure among populations under environmental stress.     

In-vivo hyperglycemic,antioxidant, histopathological changes,and simultaneous measurement of kaempferol verified by high-performance thin layer chromatography of Setaria italica in streptozotocin -induced diabetic rats

BackgroundSetaria italica (common name- foxtail, kangni) is one of the major food crops which is prominently cultivated in southern regions of India and in certain regions of Uttar Pradesh. Besides the crop’s consumption as a general source of carbohydrate rich cereal, the seeds of the crop are comprised of more fiber. So, it is recommended to add in the dietary supplementation of the diabetic people across the country.ObjectiveIn this paper, it intends to investigate the antidiabetic activity and antioxidant activity of S. italica (foxtail millet) seeds in diabetic rats.MethodsThe six genotypes of foxtail millets (S. italica) namely Kangni-1, Kangni-4, Kangni-5, Kangni-6, Kangni-7 & Kangni-10 respectively were subjected to in vitro investigations via. comprehensive metabolic panel (CMP) involving blood glucose study, Kidney & Liver function test, and antioxidant study (Catalase test; Glutathione S-transferase (GST); Superoxide Dismutase (SOD); glutathione (GSH); hiobarbituric acid reactive substances (TBARS) & Glutathione peroxidase (GPx) and were performed in vivo animal investigations in Wistar rats. The STZ induced diabetic rats were fed with doses of different S. italica seed aqueous extract to evaluate its anti-hyperglycemic activity by oral administration of SISAE. Further, it was compared with Glibenclamide which acts as one of the standard oral hypoglycemic agents.ResultsFrom achieved outcomes, a significant fall of blood glucose level (70%) produced 300 mg SISAE/kg b.w. after 6 h of extract administration. However, no change could be produced by these doses of the SISAE in normal rats’ blood glucose levels. A significant fall in glucose level along with significant glycemic control by lower HbA1c levels was observed in diabetic treated rats after 3 weeks of treatment with 300 mg of SISAE/kg b.w./day when comparing to untreated diabetic rats. Among these five genotypes of S. italica, the differences in the glycemic index were found. a significant fall could be found in blood glucose levels of Wistar rats, when every experimental rat was incorporating with the extract of different genotypes of Setaria italica L. Beauv than the rats treated with Glibenclamide in every 7 days of interval. The level of catalase, SOD, GST, GPx, GSH and TBARS showed variation while the rats were fed with the extract of S. italica in the liver test of rats. In kidney function test, the result shows that there is significant relationship between foxtail extract and kidney function of STZ induced diabetes rats. They show the change in their serum creatinine level, serum urea and serum uric acid.ConclusionThe result obtained from the study shows that the extract of S. italica seeds is capable for the hypolipidemic and antihyperglycemic activities, thereby, they serve as one of the good sources for herbal medicinal items.     

Amelioration of beryllium induced alterations in hepatorenal biochemistry and ultramorphology by co-administration of tiferron and adjuvants

Influence of adjuvants i.e., α-tocopherol (25 mg/kg, p.o.) and piperine (10 mg/kg, p.o.) on therapeutic potential of chelator tiferron (300 mg/kg, i.p.) was evaluated to encounter toxicogenic events of beryllium exposure. Albino rats were exposed to beryllium nitrate (1 mg/kg, i.p.) daily for 28 days followed by treatment of aforesaid therapeutic agents for 5 consecutive days. Results were considered to be significant at p ≤0.01 and p ≤0.05. Exposure to beryllium increased its concentration in liver, kidney and serum causing significant alterations in the activity of CYP-450 2E1 system, microsomal lipid peroxidation and protein; alkaline phosphtase, lactate dehydrogenase, γ-glutamyl transpeptidase, bilirubin, creatinine and urea in serum; activity of acid phosphatase, alkaline phosphatase, adenosine triphosphatase, glucose-6-phosphatase and succinic dehydrogenase in liver and kidney. Beryllium exposure also induced severe alterations in histopathology and ultramorphology of liver and kidney proving its toxic consequences at cellular level. Tiferron along with adjuvants dramatically reversed alterations of all variables more towards control rather than individual treatment. Study concluded that tiferron in combination with α-tocopherol and piperine respectively was beneficial in diluting beryllium induced systemic toxicity; however, combination of tiferron and piperine presented more pronounced therapeutic potential.     

Lepidium sativum alleviates diabetic nephropathy in a rat model by attenuating glucose levels,oxidative stress,and inflammation with concomitant suppression of TGF-β1

In this research, the treatment of diabetic nephropathy in rats induced by streptozotocin with L. sativium whole-plant aqueous extract was examined, and the mechanism of action was proposed. Adult male rats were grouped into: control, L. sativum, T1DM, and T1DM + L. sativum-treated groups. For 8 weeks, L. sativum S was given to rats at a final dose of 250 mg/kg. Treatment with L. sativum reduced the amount of fasting glucose, increased the amount of fasting insulin, and diminished the increase in hepatic and serum cholesterol, free fatty acid, and triglyceride levels. The level of serum LDL-c was reduced. At the level of the kidney, L. sativum reduced urine volume and albumin excretion and spiked creatinine excretion. It also attenuated the tubular damage in the rats’ kidneys and reduced the amounts of major inflammatory markers, including nuclear factor-kappaα (NF-κB), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6). Interestingly, L. sativium reduced the amount of mRNA transforming growth factor-β1 (TGF-β1), stimulated mRNA superoxide dismutase (SOD) and catalase (CAT), reduced lipid peroxide levels (MDA), and increased the glutathione (GSH), SOD, and CAT in the rat kidneys of the control and T1DM-treated group. In conclusion, L. sativum is a novel therapy against DN owing to its hypoglycemic effect, insulin-releasing, and antioxidant potential.     

Impact of Hemidesmus indicus R.Br. extract on ethanol-mediated oxidative damage in rat kidney

Abstract

The antioxidant effect of the ethanolic extract of Hemidesmus indicus R.Br. root (EHI), an indigenous Ayurvedic medicinal plant in India, was studied in rats with ethanol-induced nephrotoxicity. Administering 5 g/kg body weight/day of ethanol for 60 days to male Wistar rats resulted in significantly elevated levels of serum urea, creatinine and uric acid as well as kidney thiobarbituric acid reactive substances (TBARS), lipid hydroperoxides (LOOH) and conjugated dienes (CD) as compared to those of the experimental control rats. Decreased levels of kidney superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH), vitamin C and vitamin E were also observed on alcohol administration as compared with those of the experimental control rats. EHI was administered at a dose of 500 mg/kg body weight/day for the last 30 days of the experiment to rats with ethanol-induced kidney injury, which significantly decreased the levels of serum urea, uric acid and creatinine as well as kidney TBARS, LOOH and CD and significantly elevated the activities of SOD, CAT, GPx, GSH, vitamin C and vitamin E in kidney as compared to that of untreated ethanol-administered rats. Histopathological observations also correlated with the biochemical parameters. Thus, the data indicate that treatment with EHI offers protection against free radical-mediated oxidative stress in kidney of animals with ethanol-induced nephtrotoxicity.     

The Leu72Met polymorphism of the GHRL gene prevents the development of diabetic nephropathy in Chinese patients with type 2 diabetes mellitus

The preproghrelin (GHRL) Leu72Met polymorphism (rs 696217) is associated with obesity, reduced glucose-induced insulin secretion in healthy or diabetic subjects, and reduced serum creatinine (Scr) levels in type 2 diabetes. We evaluated the association of the Leu72Met polymorphism with measures of insulin sensitivity in non-diabetic control individuals and type 2 diabetics, and whether this variation contributes to the development of diabetic nephropathy (DN) in type 2 diabetes. A case–control study was performed of 291 non-diabetic control subjects and 466 patients with type 2 diabetes, of whom 238 had DN with overt albuminuria (DN group; albuminuric excretion rate [AER] ≥ 300 mg/24 h) and 228 did not have DN, but had diabetes for more than 10 years (non-DN group). Genotyping was performed using a TaqMan PCR assay. The Leu/Leu, Leu/Met, and Met/Met genotype frequencies were significantly different between the non-DN and DN groups (p = 0.011). The frequency of the variant genotypes (Leu/Met, Met/Met) was significantly lower in the DN group than the non-DN group (23.5 vs. 36.0 %, p = 0.003). Met/Met non-diabetic control subjects had lower BMI and Scr levels and higher eGFR level than Leu/Leu or Leu/Met individuals (p < 0.05). Leu/Met and Met/Met type 2 diabetics had significantly lower AER and Scr levels and higher eGFR level than Leu/Leu type 2 diabetics (all p < 0.001). The GHRL Leu72Met polymorphism may help to maintain normal renal function and may protect against the development of DN by reducing albuminuria and improving renal function in Chinese patients with type 2 diabetes.     

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.     

Protective effect of gallic acid isolated from Peltiphyllum peltatum against sodium fluoride-induced oxidative stress in rat’s kidney

In the present study, the nephroprotective effect of gallic acid isolated from Peltiphyllum peltatum was examined in sodium fluoride (NaF) treated rats. Nephrotoxicity was induced by 1-week intoxication of NaF at 600 ppm through drinking water. The levels of thiobarbituric acid reactive substances, reduced glutathione as well as activities of superoxide dismutase and catalase in renal tissues homogenates were determined. The serum biochemical markers of renal injuries including creatinine, serum urea, blood urea nitrogen, uric acid levels as well as the levels of phosphate and calcium were also assessed. Intoxication with NaF caused a significant increase in the levels of thiobarbituric acid reactive substances (46 % versus to control) and reduced the glutathione concentration (47 %) and the activities of superoxide dismutase (46 %) and catalase (41 %) in renal tissues homogenates. NaF intoxication also induced significant alterations in the kidney biochemical markers increasing the levels of urea, uric acid, blood urea nitrogen, creatinine, and phosphate and decreasing the levels of calcium. Daily administration of gallic acid (20 mg/kg) for 1 week before NaF intoxication brought the antioxidant–oxidant balance similar to the NaF-untreated group. Silymarin, used a standard antioxidant agent, also showed a nephroprotective activity. We concluded that NaF caused nephrotoxicity and oxidative stress in renal tissues and daily administration of gallic acid for 1 week prior to intoxication inhibited toxicity and oxidative stress.     

Antihypercholesterolemic and antioxidative effects of an extract of the oyster mushroom, Pleurotus ostreatus, and its major constituent, chrysin, in Triton WR-1339-induced hypercholesterolemic rats

Hypercholesterolemia and oxidative stress are known to accelerate coronary artery disease and progression of atherosclerotic lesions. In the present study, an attempt was made to evaluate the putative antihypercholesterolemic and antioxidative effects of an ethanolic extract of the oyster mushroom (Pleurotus ostreatus) and chrysin, one of its major components, in hypercholesterolemic rats. Hypercholesterolemia was induced in rats by a single intraperitoneal injection of Triton WR-1339 (300 mg/kg body weight (b.wt.)), which resulted in persistently elevated blood/serum levels of glucose, lipid profile parameters (total cholesterol, triglycerides, low-density lipoprotein-, and very low-density lipoprotein-cholesterol), and of hepatic marker enzymes (alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and lactate dehydrogenase). In addition, lowered mean activities of hepatic antioxidant enzymes (catalase, superoxide dismutase, and glutathione peroxidase) and lowered mean levels of nonenzymatic antioxidants (reduced glutathione, vitamin C, and vitamin E) were observed. Oral administration of the mushroom extract (500 mg/kg b.wt.) and chrysin (200 mg/kg b.wt.) to hypercholesterolemic rats for 7 days resulted in a significant decrease in mean blood/serum levels of glucose, lipid profile parameters, and hepatic marker enzymes and a concomitant increase in enzymatic and nonenzymatic antioxidant parameters. The hypercholesterolemia-ameliorating effect was more pronounced in chrysin-treated rats than in extract-treated rats, being almost as effective as that of the standard lipid-lowering drug, lovastatin (10 mg/kg b.wt.). These results suggest that chrysin, a major component of the oyster mushroom extract, may protect against the hypercholesterolemia and elevated serum hepatic marker enzyme levels induced in rats injected with Triton WR-1339.     

Hypoglycemic effect of Sclerocarya birrea {(A. Rich.) Hochst.} [Anacardiaceae] stem-bark aqueous extract in rats

This study was undertaken to evaluate the hypoglycemic effect of Sclerocarya birrea [(A. Rich.) Hochst.] subspecies caffra (Sond.) Kokwaro [family: Anacardiaceae] stem-bark aqueous extract in normal (normoglycemic) and in streptozotocin (STZ)-treated, diabetic Wistar rats. In one set of experiments, graded doses of S. birrea stem-bark aqueous extract (SB, 100-800 mg/kg p.o.) were separately administered to groups of fasted normal and fasted diabetic rats. In another set of experiments, a single dose of the plant aqueous extract (SB, 800 mg/kg p.o.) was used. The hypoglycemic effect of this single dose (SB, 800 mg/kg p.o.) of S. birrea stem-bark aqueous extract was compared with that of chlorpropamide (250 mg/kg p.o.) in both fasted normal and fasted diabetic rats. Following acute treatment, relatively moderate to high doses of S. birrea stem-bark extract (SB, 100-800 mg/kg p.o.) produced dose-dependent, significant reductions (P < 0.05-0.001) in the blood glucose concentrations of both fasted normal and fasted diabetic rats. Chlorpropamide (250 mg/kg p.o.) also produced significant reductions (P < 0.05-0.001) in the blood glucose concentrations of the fasted normal and fasted diabetic rats. Administrations of the single dose of S. birrea stem-bark aqueous extract (SB, 800 mg/kg p.o.) significantly reduced (P 0.01 < 0.001) the blood glucose levels of both fasted normal (normoglycemic) and fasted STZ-treated, diabetic rats. The results of this experimental animal study indicate that aqueous extract of Sclerocarya birrea possesses hypoglycemic activity, and thus lend credence to the suggested folkloric use of the plant in the management and/or control of adult-onset, type-2 diabetes mellitus in some African communities.