(P30-001-25) Multivitamin Supplementation Enhances Metabolic Health by Modulating Thermogenesis and Gut Microbiome in C57BL/6J Mice on a High-Fat Diet

Objectives: Obesity and metabolic disorders, often associated with high-fat diets and nutrient deficiencies, are major global health issues. This study investigates how multivitamin supplementation affects metabolic health, thermogenesis, and gut microbiome in C57BL/6J mice on a high-fat diet, aiming to identify new obesity management strategies.

Methods: Three groups of 5-week-old C57BL/6J mice were randomly assigned to one of the following diets for 12 weeks: 1. Control chow diet (CHD, 18% fat, no supplementation), 2. High-fat diet (HFD, 45% fat, no supplementation), 3. Multivitamin-supplemented HFD (Mv-HFD, 45% fat, supplemented with vitamins A (20,000), D (25,000) IU/Kg, C (1000), B1, and B5 (500) mg/Kg, in addition to basic vitamin contents of control diets. Body weight and food intake were recorded weekly. In the final two weeks, glucose tolerance, indirect calorimetry, and cold tolerance tests were performed. After fasting, mice were euthanized, and blood was collected for serum preparation, along with major organs and tissues for analysis. The gut microbiome composition was assessed using 16S rRNA gene amplicon sequencing of fecal samples and subsequent bioinformatics analysis.

Results: Mv-HFD mice showed significant health improvements over HFD mice, including 20.55% lower body weight, 53.34% and 23.14% lower IWAT and GWAT fats, respectively. They also demonstrated enhanced glucose metabolism, improved lipid profiles, and increased thermogenesis, linked to higher mRNA levels of thermogenic genes (Ucp1, Cidea, and Cd137) in IWAT. The Mv-HFD group had a healthier gut microbiome, evidenced by a lower Firmicutes/Bacteroidota ratio and increased Bacteroidetes abundance. They also showed better bacterial diversity, indicated by higher Shannon and Simpson indices, and increased beneficial genera like Bacteroides and Akkermansia while slightly enhancing beta diversity. 

Conclusions: Multivitamin supplementation in an HFD improved metabolic health and gut microbiome in mice, reducing body weight, enhancing thermogenesis, and increasing microbial diversity. This suggests multivitamins may help address obesity by modulating adipose tissue and gut microbiota.

Funding Sources: NIH U24 DK132740
NIFA Hatch Grant ALA043-1-19235
Auburn University Undergraduate Research Fellowship