Expression Of Tyrosine Hydroxylase In The Nucleus Accumbens Are Not Altered By Diet Or Fecal Transplantation In Male C57bl/6j Mice

Abstract

Multiple studies have indicated that regulation of physical activity may be largely controlled by central neural factors, such as dopamine (DA) signaling in the nucleus accumbens (NAc). It was hypothesized that metabolites produced from the gut microbiome influence DA signaling by altering the rate-limiting enzyme tyrosine hydroxylase (TH). PURPOSE: To determine whether microbial transplants from high active C57Bl/6J male mice eating a chow diet (CH) altered TH expression in the NAc of C57Bl/J male mice made low active through intake of a high fat high sugar (HF) diet. METHODS: Mice were randomly assigned to one of four groups: a chow diet (CH/CH), a high fat to chow diet plus a microbial transplant (HF/CH+), a high fat diet to chow diet (HF/CH), or a high fat diet plus a microbial transplant (HF/HF+). Changes to group base diets and microbial transplants began at week 14. Transplants were completed once a week using sample donated from the CH/CH group via oral gavage. Mice were sacrificed at the end of 17 weeks, the NAc was dissected on ice, and flash frozen in liquid nitrogen. Immunoblotting was performed using NAc lysate probed with TH antibody. Bands were normalized using β-actin and an analysis of variance was conducted. RESULTS: There were no significant differences between group means for CH/CH (1.023 ± 0.59), HF/CH+ (0.8810± 0.21), HF/CH (0.882± 0.27), or HF/HF+ (1.069± 0.32) as determined by a one-way ANOVA, (p = 0.51). CONCLUSION: TH expression in the NAc was not altered by diet or microbial transplantation from the active CH/CH group. Funding for this study was provided by the Omar Smith Endowment at Texas A&M University.