Effect of ad libitum ingestion of magnesium-rich mineral hard water on development of depressive-like phenotypes in mice exposed to chronic social defeat stress

抄録

Inflammatory alteration of the feature of gut microbiota is one of causative factors for depressive disorders. Here, we examined whether ingestion of magnesium-rich (212 ppm) mineral hard water (mineral water), which prevents gut inflammation, had prophylactic effect on development of depressive-like phenotypes in 10-days social defeat stress (SDS)-subjected C57BL/6J mice. SDS-susceptible mice with social disability exhibited increased body weight gain, and ingestion of mineral water ameliorated the increased body weight gain without any effects on daily food consumption or water intake. Relative abundance of Bacteroides spp. in colonic microbiota was decreased in water- and mineral water-ingesting SDS-susceptible mice, the level of reduction in the former being greater than in the latter, and was correlated inversely with body weight gain, and positively with sociability of mice. Overall, it is suggested that ad libitum magnesium-rich mineral water ingestion ameliorates development of psychosocial stress-induced depressive-like phenotypes partially via preventing decrease of colonic Bacteroides spp.