Effects of high-fat diet-induced gut microbiota dysbiosis: far beyond the gut

We read with great interest the attractive study by Ding N et al ,1 which reported that the dysbiosis of gut microbiota induced by high-fat diet (HFD) was one of the primary causes for the impaired sperm production and motility. It is likely mediated by elevated blood endotoxin, epididymal inflammation and the dysregulation of testicular gene expressions. We commend the authors for such a rigorous work on this critical issue. We would like to raise several concerns about this study. According to the data in this study, metagenomic sequencing may be needed to further explore the mechanisms by which certain key bacteria disrupt spermatogenesis and sperm motility. Moreover, whether probiotics supplementation can modulate gut microbiota and improve spermatogenesis and sperm motility are also worthy of exploration. Faecal microbiota transplantation (FMT) was performed in this study. …