BakuchiolvsResveratrol

Bakuchiol (meroterpene from Psoralea corylifolia) achieves retinol-like effects through RAR/RXR-independent pathways. It upregulates collagen I and III in fibroblasts via TGF-beta/Smad signaling and possibly ER-beta cross-talk. Bakuchiol downregulates MMP-1, preserving dermal collagen. It accelerates keratinocyte differentiation and stratum corneum turnover through distinct pathways. Direct antioxidant activity scavenges ROS and inhibits lipid peroxidation. Anti-inflammatory effects may involve NF-kappaB modulation. Clinical studies show comparable wrinkle reduction to 0.5% retinol; combination with retinol shows synergy. Safe during pregnancy—does not activate retinoic acid receptors.

Resveratrol activates SIRT1 (sirtuin 1), a NAD+-dependent deacetylase that deacetylates histones and non-histone targets including p53, FOXO transcription factors, and NF-κB, regulating cellular stress response, DNA repair, autophagy, and inflammatory pathways in keratinocytes and fibroblasts. It scavenges superoxide anion, hydroxyl radical, and metal-induced free radicals through its phenolic hydroxyl groups. Resveratrol inhibits NF-κB nuclear translocation and downstream cytokine production (TNF-α, IL-1β, IL-6), reducing UV-induced inflammation. It inhibits tyrosinase (mild brightening), matrix metalloproteinase-9 (MMP-9, gelatinase B) to prevent collagen and elastin breakdown, and AP-1 (c-Fos/c-Jun) to reduce photoaging-related gene expression. It may also activate Nrf2, upregulating antioxidant enzymes (HO-1, NQO1). Topical application achieves higher skin tissue concentrations than oral supplementation due to first-pass metabolism. Stability is improved in anhydrous or encapsulated formulations.