Determination of the effect of probiotic supplement on circadian rhythm genes and serum zonulin levels in mice with disturbed circadian rhythms

In our study, it was aimed to investigate the effects of probiotic supplementation on central circadian rhythm gene expressions and serum zonulin levels, a marker of intestinal barrier permeability, in mice with impaired circadian rhythms by changing the light and dark cycles every two weeks. We formed three groups of experimental animals in BALB/c genus, each consisting of 8 mice. Kontrol was control group, BSR was the group whose circadian rhythms were disrupted by changing the light/dark cycles and Probiyotik+BSR was the group whose circadian rhythms were disrupted by changing the light/dark cycles and were given probiotic supplementation at the last two months of the study. Central circadian rhythm gene expressions in mice were examined and weight gain was calculated. ELISA method was used for biochemical markers. At the end of the study, there was a statistically significant difference between the groups in terms of baseline and final weights (p <0,05). The serum zonulin levels of the mice in BSR and Probiyotik+BSR with disrupted circadian rhythms were increased compared to the control group. But, this increase was not statistically significant (p= 0,503). Although the expressions of the central circadian rhythm genes Clock, Bmal1 and Per2 varied between groups and between sampling times, the results were not statistically significant. In conclusion, it was observed that disruption of circadian rhythms by changing the light/dark cycles increased weight gain, had an increasing effect on serum zonulin levels and caused a change in expression levels on central circadian rhythm genes. It was concluded that probiotic supplementation reduced weight gain in mice with disrupted circadian rhythms compared to the group that did not receive probiotics, and had a positive effect on serum zonulin level and expression level of Per2 gene.