Objective: Hyperlipidemia is a known complication of diabetes mellitus and predisposes to coronary heart disease. The lowering of total cholesterol and low density lipoprotein (LDL)-cholesterol should reduce the incidence of coronary disease. The aim of the present study was to examine the antihyperlipidemic and antidiabetic effects of the hydroalcoholic extract of watercress (Nasturtium officinale) leaves in streptozotocin-induced diabetic rats.
Methods: Female Wistar rats were randomly divided into 4 groups: control, diabetic and diabetic rats treated with the extract of watercress (Nasturtium officinale) at doses of 100 and 200 mg/kg. Diabetic rats received the watercress extract daily in drinking water for 4 weeks since the day after diabetes confirmation. The levels of serum glucose and lipids were spectrophotometrically measured in all groups at weeks 0 (before diabetes induction), 2 and 4.
Results: There was a significant increase in serum glucose, triglycerides, total cholesterol, and LDL-cholesterol in streptozotocin-induced diabetic rats, accompanied by a decrease in high density lipoprotein (HDL)-cholesterol. The treatment of diabetic rats with hydroalcoholic extract of watercress (Nasturtium officinale) leaves over a 4-week period significantly reduced serum glucose, total cholesterol and LDL- cholesterol in comparison with diabetic untreated rats.
Conclusion: Our findings demonstrated that a 4-week treatment with watercress extract at a dose of 200 mg/kg has hypoglycemic and hypolipidemic effects in streptozotocin-diabetic rats. This implies that the consumption of watercress leaves can be helpful in reducing the complications of hyperglycemia and dyslipidemia associated with diabetes.