Researchers in the Republic of Korea found that the microbial changes correlated with obesity and adiposity markers such as leptin and lipids.
“Collectively, these results indicate differential associations between dietary supplementation and gut microbiota composition in HFD-fed mice,” they wrote in the journal Nutrients.
Although the exploratory study was relatively small, the researchers reported “biologically plausible associations that warrant further mechanistic investigation.”
Dietary regulators of metabolism
Alterations in gut composition are closely linked to the development of obesity and metabolic syndrome. Dietary patterns can influence gut bacteria and modulate intestinal permeability, immune function, and energy metabolism.
α-Lipoic acid, betaine, and L-carnitine have previously been reported to improve metabolic parameters in obesity models. While all three may exert positive effects, they have distinct biochemical functions.
α-Lipoic acid is found in meat and plant foods and is a cofactor for enzymes involved in energy metabolism and antioxidant defenses. Betaine is a natural compound present in foods such as wheat bran, wheat germ, and spinach, and is involved in fat metabolism. L-carnitine can be obtained from animal-derived foods and regulates energy metabolism by facilitating the transport of long-chain fatty acids across mitochondrial membranes.
“These distinct metabolic roles suggest that, beyond their systemic effects on adiposity and lipid metabolism, each compound may exert differential influences on gut microbial ecology under high-fat dietary conditions,” the researchers wrote.
Study details
The animal study involved five groups of six 4-week-old male mice that were fed either a control diet with 10% fat, a high-fat diet containing 60% fat, or a high-fat diet supplemented with 300 mg/kg body weight of α-Lipoic acid (AL), betaine (BT), or L-carnitine (LC) for nine weeks.
The researchers collected fecal and blood samples from the mice and conducted microbial analysis. The results revealed that all three supplement groups were associated with shifts in microbial composition compared with the high-fat-only group. AL and BT supplementation moderately modulated Firmicutes and Bacteroidetes, and LC was linked to more pronounced reductions in the Firmicutes/Bacteroidetes ratio.
“These microbial changes were correlated with obesity-related metabolic and adiposity markers, including leptin and lipid parameters,” they wrote.
“Among the three compounds, LC showed more pronounced microbiota-associated shifts that paralleled changes in metabolic and adiposity-related parameters.”
They observed potential alterations in amino acid metabolism; however, these findings reflected “inferred metabolic potential rather than direct metagenomic measurements”.
The researchers noted that the results reflect associative relationships within an experimental model and further research is needed to establish causal mechanisms.
Source: Nutrients; doi:10.3390/nu18060925; “Effect of Alpha-Lipoic Acid, Betaine, and L-Carnitine Supplementation on Gut Microbiota and Obesity Biomarkers in Mice.” Authors: H-J. Kim et al.
