Tranexamic acid protects human dermal fibroblasts from D-galactose-induced senescence via the GPR30/MAPK pathway

Background Tranexamic acid (TXA) is widely used for pigmentary disorders, but its anti-ageing potential remains unclear. This study aimed to evaluate whether topical 3% TXA improves early periorbital wrinkles in women with facial melasma and to investigate whether TXA protects human dermal fibroblasts from D-galactose-induced senescence via the GPR30/MAPK pathway.Methods Fifty women with melasma were randomized to 3% TXA serum plus moisturizer or moisturizer alone for 8 weeks, with follow-up to week 12. Periorbital wrinkles were graded using a modified Fitzpatrick Wrinkle Scale (MFWS). Separately, D-gal-induced senescence in HDFs was assessed via viability, SA-β-gal activity, senescence markers, ROS, antioxidant enzymes, SASP/ECM gene expression, and MAPK activation. GPR30 involvement was examined using antagonist G15, shRNA knockdown, and molecular docking.Results Topical TXA produced significantly greater MFWS reductions versus moisturizer alone at weeks 4, 8, and 12, with benefit persisting post-treatment. In HDFs, TXA preserved viability, reduced SA-β-gal positivity, attenuated p21/p16, restored Lamin B1, decreased ROS, and rescued antioxidant activities. TXA downregulated IL-6, IL-8, MMP1, and MMP3, and suppressed D-gal-induced ERK, JNK, and p38 phosphorylation. These effects were weakened by G15 or GPR30 knockdown; docking supported a stable TXA-GPR30 interaction.Conclusions TXA showed clinical anti-wrinkle activity in melasma patients and protected HDFs from D-gal-induced senescence, partly via GPR30-dependent modulation of oxidative stress, SASP/ECM expression, and MAPK signalling. TXA is a promising candidate for skin ageing intervention.