ABSTRACT
Coronary heart disease [CHD] is the major cause of morbidity and mortality both in industrial and developing countries. Hypercholesterolemia is the main primary contributory factor for CHD, and also there are reports that triglycerid rich lipoproleins directly or indirectly are atherogenic. In all subjects with one or more CHD risk factors in whom risk reduction is recommended non- drug therapy is a valid treatment regimen. The present study investigates the effects of ethanolic and aqueous extracts of rheum ribes [RR] of the family polygonacea on lipid concentrations in hypothyroid rabbits. To induce hypothyroidism and hyperlipidemia, 0.05% [w/w] methimazol powder was given in drinking water to rabbits with 2 +/- 0.3 kg weight, throughout the experiment. Hypothyroid animals were divided into 5 groups and treated with different regimens for 18 days as following: group A was received daily 10-15 ml of distilled water [D.W] orally; group B as positive control was received 570 mg of nicotinic acid powder in D.W orally/ day; groups C and D were received daily 4 g/kg B.W orally of aqueous and ethanolic extracts respectively and finally group E was received 6 g/kg.B.W ethanolic extract in D.W/day [this group was not concidered in results]. Blood samples were taken by the end of day 10 and 18 and serum cholesterol and triglycerid were determined by enzymatic routin laboratory methods. Aqueous extract of RR vs D.W decreased serum cholesterol by the end of day 10 and 18 by 56.34% and 84.87% [P<0.01] respectively. Triglycerid concentration was decreased by aqueous extract by day 10 and 18 by 11.29% [NS] and 66.8% [P<0.05] respectively. Ethanolic extract when compared with D.W decreased cholesterol level by 40.56% [P<0.05] and 72.27% [P<0.01] by day 10 and 18 respectively. This extract also decreased triglycerid at day 10 by 34.39% [NS] and at day 18 by 79.14% [P<0.01]. Nicotinic acid vs. D.W decreased serum cholesterol by day 10 and 18 by 54.7% [P<0.001] and 62.8% [P<0.05] respectively. Triglycerid reduction by nicotinic acid was 62.11% and 62.68% [P<0.05] by day 10 and 18 respectively. These results demonstrate that both aqueous and ethanolic extracts of RR can decrease plasma lipids in hyperlipidemic rabbits and the reductions are at the rank of or greater than that of nicotinic acid. Therefore, it may suggest that rheum ribes is potentially hypolipidemic and might be used in such status for treatment of hypercholesterolemia and hypertriglyceridemia to reduce CHD risk factors