Ameliorative Effects of Helianthus Annuus Against Nephrotoxic, Cardiac, and Haematological Disorders in Alloxan-induced Hyperglycaemia in Albino Rats.

INTRODUCTION: The study evaluated the ameliorative effects of Helianthus annuus leaf extract on nephrotoxicity, cardiac, and haematologic disorders in alloxan-induced hyperglycaemic rats. MATERIAL AND METHODS: The cold maceration method with 80% methanol was used in the preparation of H. annuus extract. Thirty alloxan-induced hyperglycaemic rats were randomly assigned to five equal groups (A-E). Groups A and B received 5% tween-20 solution in water (5 mL/kg) and glibenclamide (2 mg/kg), respectively; while groups C, D, and E received 150, 300, and 600 mg/kg of the extract, respectively, per os once daily for 21 consecutive days. The levels of serum urea, creatinine, haematological indices, and histopathological changes in the kidneys and heart were evaluated 24 h after the last treatment on day 21. RESULTS: The extract and glibenclamide significantly (P < 0.05) reduced the levels of serum urea and urea : creatinine ratio in diabetic rats when compared with the vehicle treated group. The extract and glibenclamide also ameliorated haematological disorders and kidney and cardiac damage induced by alloxan. CONCLUSION: H. annuus extract produced nephroprotective, cardioprotective, and haematoprotective effects and might prevent the advancement of diabetic complications such as diabetic nephropathy and cardiovascular diseases in diabetic patients.

Hepatoprotective and antioxidant activity of hydromethanolic extract of Daniella oliveri leaves in carbon tetrachloride-induced hepatotoxicity in rats.

BACKGROUND: Daniella oliveri is a deciduous plant that is commonly found in savanna and open grassland. Various parts of the plant is used by herbalist in the management of different ailments. The present study aims at investigating the hepatoprotective and antioxidant activity of the methanolic extract of D. oliveri leaves. METHODS: The hepatoprotective activity was investigated using carbon tetrachloride (CCl4)-induced hepatotoxicity in albino rats. The antioxidant activity was determined using both in vitro (2, 2-diphenyl-1-picrylhydrazine photometric assay) and in vivo (malondialdehyde and catalase level assay) models. RESULTS: The pretreatment with extract (100, 200, and 400 mg/kg) and silymarin (100 mg/kg) produced a significant (p<0.05) dose-dependent increase in hepatoprotective activity when compared with the negative control group. The extract (25-400 µg/mL concentration) produced a concentration-dependent increase in antioxidant activity in 2, 2-diphenyl-1-picrylhydrazine (DPPH) photometric assay. The IC50 of the extract in DPPH photometric assay was 400 µg/mL concentrations. The extract and silymarin showed a significant (p<0.05) dose-dependent increase in catalase level in treated rats when compared with the negative control group. Also, the extract and silymarin produced a significant (p<0.05) dose-dependent decrease in malondialdehyde level in treated rats when compared with the negative control group. CONCLUSIONS: The results of the study suggest that D. oliveri leaves has a potent hepatoprotective activity that may be linked to its antioxidant activities and validates its use in the traditional management of liver disorders.

Evaluation of the In Vitro and In Vivo Antioxidant Potentials of Aframomum melegueta Methanolic Seed Extract.

Aframomum melegueta Schum (Zingiberaceae) is a perennial herb widely cultivated for its valuable seeds in the tropical region of Africa. The present study evaluated the antioxidant effects of methanolic seed extract of A. melegueta. The antioxidant effects were evaluated using in vitro, 2, 2-diphenylpicrylhydrazine photometric assay and in vivo serum catalase, superoxide dismutase and thiobarbituric acid reactive substance assay method. The extract (25-400 µ g/mL concentration) produced concentration dependent increase in antioxidant activity in 2, 2-diphenylpicrylhydrazine photometric assay. The extract (400 mg/kg) showed a significant (P < 0.05) increase in serum catalase and superoxide dismutase activity when compared with the control group. The extract (400 mg/kg) showed a significant (P < 0.05) decrease in the serum level of thiobarbituric acid reactive substance when compared with the control group. These findings suggest that the seed of A. melegueta has potent antioxidant activity which may be responsible for some of its reported pharmacological activities and can be used as antioxidant supplement.

Subacute antidiabetic and in vivo antioxidant effects of methanolic extract of Bridelia micrantha (Hochst Baill) leaf on alloxan-induced hyperglycaemic rats.

The methanolic leaf extract of Bridelia micrantha was tested for subacute antidiabetic and in vivo antioxidant effects in alloxan-induced hyperglycaemic rats. The subacute treatment of the extract (125, 250 and 500 mg/kg) produced 75, 68 and 63% reduction in fasting blood sugar level respectively, on day 14 of treatment. The extract produced time-dependent effect, but did not show a dose-dependent effect. Its optimum antidiabetic activity was noted at the dose of 125 mg/kg and this was comparable to glibenclamide 2 mg/kg (positive control). The extract (125 mg/kg) showed good oral glucose tolerance test (OGTT) effect in both normoglycaemic and hyperglycaemic rats. The OGTT effect of the extract (125 mg/kg) did not differ significantly (p>0.05) from glibenclamide (2 mg/kg). The antioxidant effect of the extract was assayed through the determination of the level of thiobarbituric acid reactive substance (TBARS) and catalase activity. The extract produced a dose-dependent decrease in the serum level of TBARS and gave its optimum catalase activity at the dose of 500 mg/kg. This study suggests that the B. micrantha extract has antihyperglycaemic and antioxidant activities. Therefore, could be a potential source of novel antidiabetic and antioxidant agent for the management of diabetes mellitus.