Nonthermal plasma treated solution inhibits adipocyte differentiation and lipogenesis in 3T3-L1 preadipocytes via ER stress signal suppression

The accumulation and differentiation of adipocytes contribute to the development of obesity and metabolic diseases. It is well-known that interactions of transcription factors such as peroxisome proliferator-activated receptor gamma (PPARγ), CCAAT/enhancer binding protein α (C/EBPα), and endoplasmic reticulum (ER) stress are required for adipogenesis. Recently, use of nonthermal atmospheric plasma (NTP) is expanding from the biomedical field into various other fields. In this study, we investigated whether nonthermal plasma-treated solution (NTS) has an inhibitory effect on adipogenesis and elucidated its mechanisms. Our results demonstrated that NTS significantly inhibited pre-adipocyte differentiation into adipocytes based on Oil Red O staining and triglyceride accumulation. Moreover, NTS treatment suppressed the mRNA and protein expression levels of key adipogenic transcription factors, and adipocyte-specific genes. NTS also down-regulated endoplasmic reticulum stress-related proteins. Consistent with in vitro studies, an animal study using a mouse model of diet-induced obesity showed that NTS treatment reduced body weight and fat, ER stress/UPR, triglyceride, and adipogenic marker level without altering food intake. These findings indicate that NTS inhibits adipogenic differentiation, and provide a mechanistic explanation of the inhibitory effect of NTS on adipogenesis. Taken together, our results suggest that NTS might be useful to treat obesity and obesity-related diseases.