Barley Protein LFBEP-C1 from Lactiplantibacillus plantarum dy-1 Fermented Barley Extracts by Inhibiting Lipid Accumulation in a Caenorhabditis elegans Model.

Objective: This study aimed to investigate the lipid-lowering activity of LFBEP-C1 in high glucose-fed Caenorhabditis elegans (C. elegans).

Methods: In this study, the fermented barley protein LFBEP-C1 was prepared and tested for its potential anti-obesity effects on C. elegans. The worms were fed Escherichia coli OP50 ( E. coli OP50), glucose, and different concentrations of LFBEP-C1. Body size, lifespan, movement, triglyceride content, and gene expression were analyzed. The results were analyzed using ANOVA and Tukey's multiple comparison test.

Results: Compared with the model group, the head-swing frequency of C. elegans in the group of LFBEP-C1 at 20 μg/mL increased by 33.88%, and the body-bending frequency increased by 27.09%. This indicated that LFBEP-C1 improved the locomotive ability of C. elegans. The average lifespan of C. elegans reached 13.55 days, and the body length and width of the C. elegans decreased after LFBEP-C1 intake. Additionally, LFBEP-C1 reduced the content of lipid accumulation and triglyceride levels. The expression levels of sbp-1, daf-2, and mdt-15 significantly decreased, while those of daf-16, tph-1, mod-1, and ser-4 significantly increased after LFBEP-C1 intake. Changes in these genes explain the signaling pathways that regulate lipid metabolism.

Conclusion: LFBEP-C1 significantly reduced lipid deposition in C. elegans fed a high-glucose diet and alleviated the adverse effects of a high-glucose diet on the development, lifespan, and exercise behavior of C. elegans. In addition, LFBEP-C1 regulated lipid metabolism mainly by mediating the expression of genes in the sterol regulatory element-binding protein, insulin, and 5-hydroxytryptamine signaling pathways.