Studies on the Hypolipidemic and Antioxidant Effects Of Tender Cluster Beans (Cyamopsis Tetragonoloba) In Experimental Animals.

The beneficial anti-hypercholesterolemic effect of dietary cluster beans as a source of
soluble dietary fibre was evaluated in high cholesterol diet induced hypercholesterolemia
in experimental rats. Freeze dried tender cluster beans (CB) was included at 12.5 and
25% levels in the diet of animals maintained for 8 weeks either on high (0.5%)
cholesterol diet or basal control diet. Significant anti-hypercholesterolemic effect was
seen in cluster bean fed animals, the decrease in serum cholesterol being particularly in
the LDL associated fraction and also a beneficial increase in HDL-cholesterol by dietary
cluster beans. Hepatic lipid profile showed a significant decrease in both cholesterol and
triglycerides as a result of feeding CB along with high cholesterol diet. This beneficial
influence of dietary CB on the lipid profile of serum, liver and bile in high cholesterol fed
situation was significantly potentiated by garlic when included in the diet along with CB.
Tender CB, a rich source of soluble dietary fibre (guar gum) was also explored for its
potential in weight management in rats maintained on high-fat diet (HFD). The impact of
dietary CB in weight management was examined in terms of body weight gain,
absorption and elimination of dietary fat, accumulation of dietary fat in adipose, and
influence on lipogenic enzymes and lipolytic enzymes. The study indicated the potential
of dietary cluster beans as a weight management agent by causing lowered fat absorption,
higher diversion of dietary fat through feces, enhanced lipolysis through increased
activity of hormone sensitive lipase causing lowering of adipose weight and increased
mobilization of accumulated fat. All these contributed to reduction in weight gain by the
animals maintained on HFD by inclusion of cluster beans in the diet. The hypolipidemic
and weight reducing influence of dietary tender cluster bean was potentiated by
capsaicin, a known thermogenic spice compound when included along with CB in highfat
fed rats.
The gastrointestinal protective effect of CB, w.r.t. activities of antioxidant enzymes
and concentration of antioxidant molecules was examined in rats. Dietary intervention
with tender cluster beans significantly enhanced the activities of antioxidant enzymes –
superoxide dismutase, catalase, glutathione reductase, glutathione-S-transferase and
glutathione peroxidase and concentrations of antioxidant molecules in both gastric and
intestinal mucosa. There was also an indication that gastroprotective effect of CB was
even higher when combined with capsaicin in terms of increased antioxidant status.
Dietary CB was also found to alleviate the diminished activities of antioxidant enzymes
and antioxidant molecules in gastric and intestinal mucosa under conditions of ethanolinduced
oxidative stress. Gastro-protective effect of CB was also reflected in its positive
effect on gastric mucosal glycoproteins, thereby lowering mucosal injury. Incidentally,
serum and liver also showed an elevated antioxidant status as a result of dietary CB under
conditions of oxidative stress. Dietary CB also improved antioxidant status in
hypercholesterolemic condition in rats as indicated by higher concentrations of
antioxidant molecules and activities of antioxidant enzymes in circulation and hepatic
tissue. The antioxidant effect of dietary CB was potentiated by co-administration of garlic
thus suggesting an additive influence in protection against oxidative stress in
hypercholesterolemic situation.