%0 Journal Article
%T Polystyrene nano-plastics impede skeletal muscle development and induce lipid accumulation via the PPARγ/LXRβ pathway in vivo and in vitro in mice.
%A Xu R
%A Cao JW
%A Geng Y
%A Xu TC
%A Guo MY
%J Arch Toxicol
%V 0
%N 0
%D 2024 Aug 3
%M 39096369
%F 6.168
%R 10.1007/s00204-024-03831-1
%X Nano-plastics (NPs) have emerged as a significant environmental pollutant, widely existing in water environment, and pose a serious threat to health and safety with the intake of animals. Skeletal muscle, a vital organ for complex life activities and functional demands, has received limited attention regarding the effects of NPs. In this study, the effects of polystyrene NPs (PS-NPs) on skeletal muscle development were studied by oral administration of different sizes (1 mg/kg) of PS-NPs in mice. The findings revealed that PS-NPs resulted in skeletal muscle damage and significantly hindered muscle differentiation, exhibiting an inverse correlation with PS-NPs particle size. Morphological analysis demonstrated PS-NPs caused partial disruption of muscle fibers, increased spacing between fibers, and lipid accumulation. RT-qPCR and western blots analyses indicated that PS-NPs exposure downregulated the expression of myogenic differentiation-related factors (Myod, Myog and Myh2), activated PPARγ/LXRβ pathway, and upregulated the expressions of lipid differentiation-related factors (SREBP1C, SCD-1, FAS, ACC1, CD36/FAT, ADIPOQ, C/EBPα and UCP-1). In vitro experiments, C2C12 cells were used to confirm cellular penetration of PS-NPs (0, 100, 200, 400 μg/mL) through cell membranes along with activation of PPARγ expression. Furthermore, to verify LXRβ as a key signaling molecule, silencing RNA transfection experiments were conducted, resulting in no increase in the expressions of PPARγ, LXRβ, SREBP1C, FAS, CD36/FAT, ADIPOQ, C/EBPα and UCP-1 even after exposure to PS-NPs. However, the expressions of SCD-1and ACC1 remained unaffected. The present study evidenced that exposure to PS-NPs induced lipid accumulation via the PPARγ/LXRβ pathway thereby influencing skeletal muscle development.