Abstract

Compound probiotics have been widely used and commonly co-administered with other drugs for treating various chronic illnesses, yet their effects on drug pharmacokinetics remain underexplored. This study elucidated the impact of VSL#3 on the metabolism of probe drugs for cytochrome P450 enzymes (CYP450s), specifically omeprazole, tolbutamide, midazolam, metoprolol, phenacetin and chlorzoxazone. Male Wistar rats were administered with drinking water containing VSL#3 or not for 14 days and then intragastrically administered a CYP450s probe cocktail; This was done to investigate the host CYP450s metabolic phenotype. Stool, liver/jejunum and serum samples were collected for 16S rRNA sequencing, RNA sequencing, and bile acid profiling. The results indicated significant differences in both alpha and beta diversity of intestinal microbial composition between the probiotic and vehicle groups in rats. In the probiotic group, the bioavailability of omeprazole increased by 269.9%, whereas those of tolbutamide and chlorpropamide decreased by 28.1% and 27.4%, respectively. The liver and jejunum exhibited 1,417 and 4,004 differentially expressed genes, respectively, between the two groups. In the probiotic group, most of CYP450s genes were upregulated in the liver but downregulated in the jejunum. The expression of genes encoding metabolic enzymes and drug transporters also changed. The serum conjugated bile acids in the probiotic group were significantly reduced. Shorter duodenal villi and longer ileal villi were found in the probiotic group. In summary, VSL#3 administration altered the gut microbiota, host drug-processing gene expression, and the intestinal structure in rats, which could be reasons for pharmacokinetic changes.

Significance Statement This study focused on the effects of the probiotic VSL#3 on the pharmacokinetic profile of CYP450s probe drugs and the expression of host drug metabolism genes. Compared with previous studies, the current study provides a comprehensive explanation for the host drug metabolism profile modified by probiotics, here combined with the bile acid profile and histopathological analysis.