A research team led by Professor Liu Yanqun from Wuhan University's School of Nursing has made a significant breakthrough in understanding the relationship between prenatal depression and gut microbiota.

Their study, titled "Prenatal depression-associated gut microbiota induces depressive-like behaviors and hippocampal neuroinflammation in germ-free mice", was recently published in Translational Psychiatry.

This groundbreaking research provides direct experimental evidence of a causal link between gut microbiota dysbiosis and prenatal depression. Using cross-species fecal microbiota transplantation, the researchers demonstrated that imbalances in gut microbiota associated with prenatal depression could induce depressive-like behaviors in germ-free mice.

The study identified a mechanism wherein dysbiotic microbiota alter host metabolic functions, activating the Nuclear Factor kappa B (NF-κB) signaling pathway and leading to microglial-mediated neuroinflammation.

Previous investigations by Liu’s team had already highlighted significant differences in gut microbiota composition between pregnant women with prenatal depression and their healthy counterparts. However, the direct causality of these differences in triggering prenatal depression was not previously established.

To address this, the research team selected fecal samples from both prenatally depressed and healthy pregnant women from an earlier cohort. These samples were used to prepare fecal microbiota suspensions, which were then transplanted into germ-free mice. Behavioral experiments showed that mice receiving microbiota from prenatally depressed women exhibited marked depressive-like behaviors.

This study confirms, from a causal perspective, that gut microbiota dysbiosis plays a crucial role in the development of prenatal depression, with mechanisms linked to LPS-NF-κB pathway-mediated neuroinflammation.