NR1D1 and skin aging: Puerariae lobatae radix (PLR), the root of kudzu vine, protects against UVB-induced skin aging by functioning as a REVERBα antagonist—it enhances BMAL1 expression, subsequently elevating NRF2 transcriptional activity and protein levels, upregulating antioxidant gene expression, and ultimately mitigating UVB-induced skin aging through ROS scavenging and senescence suppression.