Hypolipidemic effect of soluble dietary fiber (galactomannan) isolated from fenugreek seeds in WNIN (GR-Ob) obese rats

Abstract

The hypolipidemic effect of a soluble dietary fiber isolated from fenugreek seeds rich in galactomannan was studied in WNIN/GR-Ob a mutant obese rat strain. The study consists of fifty five obese rats randomly divided into five groups of 6 males and 5 females in each group. Group I was fed with control diet, while Group II and IV were fed with diet containing 10 and 20% fenugreek seeds, whereas Group III and V received diet containing 2.5 and 5% galactomannan respectively for 9 weeks. The results showed significant (p<0.05) reduction in gain in body weight in experimental animals without any effect on their food intake. After 9 weeks, significant (p<0.05) reduction was observed in lipemic parameters (triglycerides and total cholesterol) in experimental groups from 3rd week onwards. The HMG-CoA reductase activity was significantly low in control group as compared with experimental groups. Concomitantly fecal neutral sterols excretion was significantly (p<0.05) higher in experimental groups, compared to control. The results which demonstrated the hypolipidemic effect of galactomannan extracted from fenugreek seeds for the first time in obese rats could be due to the increased activity of HMGA-CoA reductase, which is a key hepatic regulatory enzyme in experimental animals leading to excretion of bile acids and neutral sterols in feces. Key words: Fenugreek seeds, galactomannan, soluble dietary fiber, hypolipidemic effect, obese rat, bile acids, neutral sterols, HMGA-CoA reductase.