Metabolic syndrome is a condition that often leads to diabetes, heart disease, and even stroke and obesity, a chronic worldwide epidemic is a leading cause of metabolic syndrome (MetS). It has also been shown that the microbiome may be an important factor in the development of obesity and subsequently, MetS, possibly due to its impact on gut barrier integrity and inflammation. While probiotics have been used as an intervention in several animal studies on obesity and MetS, there have not been sufficient results in humans to show it is having a positive effect.
Despite significant amounts of research, the question still remains if probiotics are having a lasting effect on the gut when administered. It is not clear if taking a probiotic is colonizing in the gut or if it is only providing an acute response during the timeframe it is being administered. A team of scientists published their work showing the effect that Lactobacillus casei Shirota (LcS) had on patients with MetS. The researchers administered LcS to 13 patients with MetS and 15 individuals received no LcS. They sequenced their microbiota composition from stool samples and compared it to healthy controls.
They found that LcS did not have an impact on Bacteroidetes/Firmicutes ratio and that it was slightly higher in the healthy controls. Serum bile acids were similarly not affected by LcS administration. While they did see small microbiota changes, LcS was not able to change the Bacteroidetes/Firmicutes ratio or gut barrier dysfunction, two important staples of metabolic syndrome.
While the small sample size of the patient cohorts may have been a factor in the failure to observe microbiota changes after probiotic administration, it was still important to see that probiotics may not always have the intended consequences we are seeking. In this study, probiotic administration did not provide a benefit to the Metabolic syndrome patients and further studies will be needed to better understand the microbiome implications of probiotics.