Cholesterol lowering in pigs through enhanced bacterial bile salt hydrolase activity

Abstract

The effect of feeding liveLactobacillus reutericells containing active bile salt hydrolase (BSH) on plasma cholesterol levels was studied in pigs. During an experiment lasting 13 weeks, twenty pigs were fed on a high-fat, high-cholesterol, low-fibre diet for the first 10 weeks, and a regular pig diet for the last 3 weeks. One group of animals received, twice daily, 11·25 (SD 0·16) log10colony forming units of the potential probiotic bacteria for 4 weeks (from week 3 until week 7). From week 8 onwards, the treated group was again fed on the same diet as the control group without additions. The total faecalLactobacilluscounts were only significantly higher in the treated pigs during the first 2 weeks ofL. reuterifeeding. Based on limited data, it was suggested that the administeredLactobacillusspecies had caused a temporary shift within the indigenousLactobacilluspopulation rather than permanently colonizing the intestinal tract. The probiotic feeding brought about significant lowering (P≤ 0·05) of total and LDL-cholesterol concentrations in the treated pigs compared with the control pigs, while no change in HDL-cholesterol concentration was observed. The data for faecal output of neutral sterols and bile salts were highly variable between the animals of each group, yet they indicated an increased output in the treated pigs. Although the blood cholesterol levels went up in both groups during the 3 weeks following theLactobacillusadministration period, significantly lower serum total and LDL-cholesterol levels were observed in the treated pigs. During the final 3 weeks of normalization to the regular diet, cholesterol concentrations significantly decreased in both animal groups and the differences in total and LDL-cholesterol concentrations between the groups largely disappeared.