Pre- and Postnatal Fine Particulate Matter Exposure and Renal Fibrogenesis in Adult Male Rats: The Role of Vitamin D Supplementation.

Prolonged exposure to fine particulate matter (PM) has been implicated in accelerated aging, including organ fibrosis. This study aimed to investigate whether prenatal and postnatal PM exposure promotes renal fibrogenesis in adulthood and whether long-term vitamin D supplementation alleviates associated renal injury. Pregnant Sprague-Dawley rats were randomly assigned to three groups: control (normal saline, NS), PM exposure, and PM exposure with vitamin D supplementation during gestation and lactation ( = 3/group). Male offspring were subsequently exposed to the same conditions from postnatal weeks 3 to 8 ( = 7/group). On postnatal day 56, PM-exposed rats showed lower body weight and more severe glomerular and tubulointerstitial damage compared to controls. Serum calcium levels were elevated in the PM group. The expression of intrarenal renin, transforming growth factor-β1, α-smooth muscle actin, and vimentin was upregulated, accompanied by increased collagen deposition. Long-term vitamin D supplementation reversed most of these changes, except for intrarenal vimentin expression and serum calcium levels. These findings indicate that prenatal and postnatal PM exposure can activate intrarenal renin signaling and fibrogenic pathways, contributing to renal fibrosis later in life. Long-term vitamin D supplementation may provide partial protective effects against PM-induced renal fibrogenesis.