# Effect of Alpha-Lipoic Acid, Betaine, and L-Carnitine Supplementation on Gut Microbiota and Obesity Biomarkers in Mice

## TL;DR

This study explores how supplements like alpha-lipoic acid, betaine, and L-carnitine affect gut bacteria and obesity markers in mice on a high-fat diet.

## Contribution

The study reveals distinct effects of three supplements on gut microbiota and obesity-related biomarkers in a mouse model.

## Key findings

- AL and BT moderately modulated Firmicutes and Bacteroidetes taxa.
- LC significantly reduced the Firmicutes/Bacteroidetes ratio and specific genera like Christensenellaceae.
- Microbial changes correlated with metabolic markers like leptin and lipid levels.

## Abstract

Background/Objectives: This exploratory study (n = 6 per group) investigated the associations between supplementation with α-lipoic acid (AL), betaine (BT), and L-carnitine (LC) and gut microbiota composition in a high-fat diet (HFD)-induced obesity mouse model. Methods: Four-week-old male C57BL/6J mice were fed a control diet (10% fat), HFD (60% fat), or HFD supplemented with AL, BT, or LC (300 mg/kg BW/day) for nine weeks. Results: All three compounds were associated with shifts in microbial composition compared to the HFD-only group. While AL and BT supplementation moderately modulated specific Firmicutes and Bacteroidetes taxa, LC supplementation was linked to a more pronounced reduction in the Firmicutes/Bacteroidetes ratio and a decreased abundance of genera such as Christensenellaceae, Lachnospiraceae, and Coprococcus 3. These microbial changes were correlated with obesity-related metabolic and adiposity markers, including leptin and lipid parameters. Furthermore, functional profiling via PICRUSt suggested potential alterations in amino acid metabolism; however, these findings represent inferred metabolic potential rather than direct metagenomic measurements. Conclusions: Collectively, these results indicate differential associations between dietary supplementation and gut microbiota composition in HFD-fed mice. Although this study was conducted within an exploratory framework and utilized a modest sample size, the observed microbial shifts consistently paralleled metabolic alterations, supporting biologically plausible associations that warrant further mechanistic investigation.