PPARγ As a Potential Target for Adipogenesis Induced by Fine Particulate Matter in 3T3-L1 Preadipocytes.

Mounting evidence has shown that ambient PM 2.5 exposure is closely associated with the development of obesity, and adipose tissue represents an important endocrine target for PM 2.5 . In this study, the 3T3-L1 preadipocyte differentiation model was employed to comprehensively explore the adipogenic potential of PM 2.5 . After 8 days of PM 2.5 exposure, adipocyte fatty acid uptake and lipid accumulation were significantly increased, and adipogenic differentiation of 3T3-L1 cells was promoted in a concentration-dependent manner. Transcriptome and lipidome analyses revealed the systematic disruption of transcriptional and lipid profiling at 10 μg/mL PM 2.5 . Functional enrichment and visualized network analyses showed that the peroxisome proliferator-activated receptor (PPAR) pathway and the metabolism of glycerophospholipids, glycerolipids, and sphingolipids were most significantly affected during adipocyte differentiation. Reporter gene assays indicated that PPARγ was activated by PM 2.5 , demonstrating that PM 2.5 promoted adipogenesis by activating PPARγ. The increased transcriptional and protein expressions of PPARγ and downstream adipogenesis-associated markers ( e.g. , Fabp4 and CD36) were further cross-validated using qRT-PCR and western blot. PM 2.5 -induced adipogenesis, PPARγ pathway activation, and lipid remodeling were significantly attenuated by the supplementation of a PPARγ antagonist (T0070907). Overall, this study yielded mechanistic insights into PM 2.5 -induced adipogenesis in vitro by identifying the potential biomolecular targets for the prevention of PM 2.5 -induced obesity and related metabolic diseases.