Correlation of Midgut Microbiota and Metabolic Syndrome-Related Lipids in Hemolymph Between Obese and Lean Silkworm Strains

Metabolic syndrome is a global health crisis. However, there are no effective therapeutic strategies for metabolic syndrome. Therefore, this study was conducted to find out a novel silkworm-based metabolic syndrome model that bridges microbial ecology and metabolic dysregulation by integrating hemolymph lipids and midgut microbiota. Our results showed that the levels of HDL-C in the hemolymph of the lean silkworm strain were significantly higher than that in the obese silkworm strain. Furthermore, correlation analysis revealed that <i>Lactococcus</i> and <i>Oceanobacillus</i> were positively related to HDL-C levels, while <i>SM1A02</i> and <i>Pseudonocardia</i> were negatively associated with HDL-C levels. These relationships between the identified bacteria in the midgut and HDL-C, known as the "good" lipid, in the hemolymph could help guide the development of new treatments for obesity and metabolic problems like high cholesterol in humans. Overall, our results not only established a framework for understanding microbiota-driven lipid dysregulation in silkworms but also offered potential probiotic targets and a bacterial biomarker for obesity and metabolic dysfunction intervention in humans.