Gut microbiota impairs spermatogenesis in Ggt1-deficient mice

This study investigates the relationship between male infertility and gut microbiota dysbiosis, focusing on its impact on spermatogenesis. RNA sequencing was performed on wild-type (WT) mice and gamma-glutamyltransferase 1 knockout (KO) mice, with additional transcriptomic analysis conducted on mice after fecal microbiota transplantation (FMT), including those receiving fecal microbiota from WT mice (FMT-WT) and those receiving fecal microbiota from KO mice (FMT-KO). KO mice exhibit male infertility features, such as reduced numbers of germ cells and Leydig cells in the testes, along with an increased proportion of abnormal sperm. Metagenomic analysis of fecal microbiota reveals significant differences between KO and WT mice. Fecal microbiota from KO mice results in decreased germ cell and sperm counts, and an increased proportion of abnormal sperm in recipient mice. Transcriptomic analysis shows reduced expression levels of kallikrein family members (Klk1b21, Klk1b22, Klk1b24, Klk1b27) in Leydig cells of KO and FMT-KO mice.