Effect of a probiotic fermented milk supplementation on behavior and sleep.

This study attempted to analyze the effect of supplementing Wistar-Kyoto rats with fermented milk containing the probiotic Bifidobacterium animalis BB-12 and pomegranate juice on the microbiota-gut-brain axis of rats, with special focus on their behavior, sleep patterns, and response to stress. This study was divided into two experiments: (1) For the behavioral analysis the animals were divided into two groups: Fermented probiotic milk (BB + 1) and control (BB-). (2) For the sleep analysis the animals were divided into two groups: Fermented probiotic milk (BB + 2) and control (H2O). For the behavioral analysis, the open field method was used, which evaluates the behavior after ten, twenty, and thirty days of supplementation. For sleep analysis, the animals were submitted to implantation of electrodes and 24 h polysomnography, followed by 48 h sleep deprivation (REM) and 48 h polysomnography, then euthanized 100 days after the beginning of the experiment. In addition, animal feces were collected before and after sleep deprivation to assess its effects on the microbiota. A decrease in anxiety-related behaviors was observed in the supplemented animals and an increase in sleep efficiency and a reduction in the number of awakenings of the animals before deprivation. It has also been observed that sleep deprivation decreased the amount of total bacterial DNA. The number of copies of genomes of the genus Bifidobacterium did not differ in both groups.