Heat-Killed Enterococcus faecalis Prevents Adipogenesis and High Fat Diet-Induced Obesity by Inhibition of Lipid Accumulation through Inhibiting C/EBP-α and PPAR-γ in the Insulin Signaling Pathway

• Published in: Nutrients Vol. 14; no. 6; p. 1308
• Main Authors: Lee, Jin-Ho, Woo, Keun-Jung, Kim, Min-Ah, Hong, Joonpyo, Kim, Jihee, Kim, Sun-Hong, Han, Kwon-Il, Iwasa, Masahiro, Kim, Tack-Joong
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 20.03.2022; MDPI
• Subjects: Adipocytes; Adipogenesis; Animals; Body fat; Cell cycle; cholesterol; Diet; Diet, High-Fat - adverse effects; Enterococcus faecalis; High density lipoprotein; high fat diet; Hot Temperature; inflammation; insulin; Insulin - pharmacology; insulin receptors; Insulin resistance; Lipids; Microscopy; neoplasm progression; Obesity; Obesity - etiology; Obesity - metabolism; Obesity - prevention & control; oral administration; pandemic; phosphorylation; PPAR gamma - metabolism; Proteins; Rats; sedentary lifestyle; Signal Transduction; Stains & staining; triacylglycerols; Triglycerides - pharmacology; Western blotting; United States > US; Enterococcus faecalis; adipogenesis; 3T3-L1; high fat diet; obesity; parabiotic
• ISSN: 2072-6643; 2072-6643
• DOI: 10.3390/nu14061308

Increasing consumption of food with high caloric density and a sedentary lifestyle have influenced the increasing obesity prevalence worldwide. The recent pandemic has contributed to this problem. Obesity refers to a state in which lipid accumulates excessively in adipocytes and adipose tissues. Dried heat-killed Enterococcus faecalis (EF-2001) prevents allergic mechanisms, inflammation, and tumor progression. In the present study, we investigated the effects of EF-2001 on high fat diet (HFD)-induced obese rats. The degree of obesity in experimental rats was reduced after 6 weeks of oral administration of 3 mg/kg or 30 mg/kg dosages of EF-2001, indicating regulating effects in rats with HFD-induced obesity. We found that EF-2001 decreased the amounts of total cholesterol, triglyceride, and non-high density lipoprotein (HDL) in HFD-induced obese rats. The effects of EF-2001 on 3T3-L1 adipocytes stained with Oil red O stain are shown in reductions of lipid accumulation, respectively. In addition, we examined the relationships between EF-2001 treatment and mechanisms for the insulin signaling of adipogenesis in 3T3-L1 cells. EF-2001 induced down-regulation in phosphorylation of Erk, JNK, and Akt through the inhibition of insulin receptor phosphorylation. EF-2001 inhibits the expressions of C/EBP-α and PPAR-γ, a lipid metabolism-related transcription factor through confocal microscope observation and Western blot on 3T3-L1 adipocytes and HFD-induced obese rats. Based on our results, intake of EF-2001 significantly prevented HFD-induced obesity in rats through inhibition of C/EBP-α and PPAR-γ in the insulin signaling pathway on lipid accumulation.