Accelerated Attenuation of Pre-Formed Cholesterol Gallstones by Dietary Tender Cluster Beans (Cyamopsis tetragonoloba) in Mice

Dietary soluble fibre-rich tender cluster beans (Cyamopsis tetragonoloba) (CB) is previously shown to reduce the susceptibility for cholesterol gallstone (CGS) formation in experimental mice. The present study evaluated if dietary CB could also accelerate dissolution of pre-formed CGS in mice. The possible additive influence of dietary fibre-rich CB and sulfur compounds-rich garlic in dissolving CGS was also evaluated. CGS was induced with a high-cholesterol diet for ten weeks. CB (10%) and garlic (1%) were included individually and in combination in the diet of gallstoneinduced mice for another ten weeks. CB, garlic, and CB+garlic reduced the preestablished CGS by 61, 50, and 72%, respectively, in 10 weeks as compared to 27% regression observed with the control diet. There was a reduction in cholesterol saturation index and ratios of cholesterol: bile acid and cholesterol: phospholipid in the bile, facilitating the desaturation of cholesterol. mRNA expression of CYP7A was up-regulated in CB-fed animals. CB+garlic produced a higher up-regulation of mRNA expression of CYP7A and CYP27. These results corroborate with the observed increase in the bile acid pool as a result of these dietary interventions. Acceleration of the regression of preformed CGS is complimentary to the previously reported CGSpreventive influence of dietary CB.