Maternal PM2.5 Exposure Impairs Inguinal White Adipose Tissue Plasticity in Middle-aged Male Mouse Offspring

In this study, we investigated the long-term adverse metabolic effects of maternal fine particulate matter (PM2.5) exposure on offspring, systematically characterized the pathogenic remodeling of inguinal white adipose tissue (iWAT) in middle-aged male offspring through scRNA-seq, and explored the underlying mechanisms of iWAT fibrosis under in vivo and in vitro conditions. Overall design: Pregnant mice were randomly assigned to the filtered air (FA) group and the concentrated PM2.5 exposure group (PM2.5). The exposure protocol was 12 hours per day (from 08:00 to 20:00) for 19 successive days (gestational day (GD) 0-18) using a whole-body inhalation exposure system located on the campus of Zhejiang Chinese Medical University (ZCMU). At birth (postnatal day 0, PND 0), the pups were indiscriminately culled to 6-8 per litter. The remaining pups were reared with their dams in a clean air environment. At PND 21, all pups were weaned and caged according to sex. Then, all weaned offspring were fed a standard chow diet and weighed weekly. At PND 56 (adult) and PND 365 (12 months old, middle-aged), the offspring from each litter were euthanized and necropsied to collect serum and organs (i.e., iWAT, eWAT, and BAT) for further analysis. The fresh iWAT isolated from middle-aged male offspring was used to perform scRNA-seq.