Effects on weight gain and gut microbiota in rats given bacterial supplements and a high-energy-dense diet from fetal life through to 6 months of age.

The aim of the present study was to assess the long-term effects of a high-energy-dense diet, supplemented with Lactobacillus plantarum (Lp) or Escherichia coli (Ec), on weight gain, fattening and the gut microbiota in rats. Since the mother's dietary habits can influence offspring physiology, dietary regimens started with the dams at pregnancy and throughout lactation and continued with the offspring for 6 months. The weight gain of group Lp was lower than that of groups C (control) and Ec (P = 0·086). More retroperitoneal adipose tissue (P = 0·030) and higher plasma leptin (P = 0·035) were observed in group Ec compared with group Lp. The viable count of Enterobacteriaceae was higher in group Ec than in group Lp (P = 0·019), and when all animals were compared, Enterobacteriaceae correlated positively with body weight (r 0·428, P = 0·029). Bacterial diversity was lower in group Ec than in groups C (P ≤ 0·05) and Lp (P ≤ 0·05). Firmicutes, Bacteroidetes and Verrucomicrobia dominated in all groups, but Bacteroidetes were more prevalent in group C than in groups Lp (P = 0·036) and Ec (P = 0·056). The same five bacterial families dominated the microbiota of groups Ec and C, and four of these were also present in group Lp. The other five families dominating in group Lp were not found in any of the other groups. Multivariate data analysis pointed in the same directions as the univariate statistics. The present results suggest that supplementation of L. plantarum or E. coli can have long-term effects on the composition of the intestinal microbiota, as well as on weight gain and fattening.

Lactobacillus plantarum 299v enhances the concentrations of fecal short-chain fatty acids in patients with recurrent clostridium difficile-associated diarrhea.

Our objective was to document how intake of Lactobacillus plantarum 299v affects the concentrations of fecal organic acids during and after metronidazole treatment in 19 patients with recurrent Clostridium difficile-associated diarrhea. Fecal samples were analyzed by gas-liquid chromatography. After intake of metronidazole a significant decrease in total short-chain fatty acids was seen in the placebo group (from 77.1 to 45.5 micromol/g; P=0.028) but not in the Lactobacillus group (79.8-60.4 micromol/g). In addition, a statistically significant difference between treatment groups was noted for butyrate (5.6-1.2 micromol/g in the placebo group vs. 7.6-5.6 micromol/g in the Lactobacillus group; P=0.047). At the end of the study and after cessation of placebo or Lactobacillus, the total short-chain fatty acids rose to the same levels as before antibiotic treatment in the placebo group. Both treatment groups showed a significant decrease in concentrations of succinate at the end of the study in comparison to the time when metronidazole intake was stopped (6.3-1.5 micromol/g in the placebo group versus 9.3-0.9 micromol/g in the Lactobacillus group; P=0.028). The present study of fecal samples from a clinical trial is the first to demonstrate that administration of Lactobacillus plantarum 299v reduces the negative effects of an antibiotic on colonic fermentation. The intake of this probiotic strain may thereby provide an additional benefit for patients with recurrent Clostridium difficile-associated diarrhea.