Phytochemical analysis and impact of Citrus hystrix peel water extract on proliferation and migration of skin keratinocytes by activating FAK/Src/MAPK/Akt pathway

Introduction: A multicomplex process of cutaneous wound healing required various mediators at both cellular and molecular levels. Citrus hystrix, a common Rutaceae spice, is used as an ingredient of food and traditional medicine to alleviate various health conditions. However, the citrus peel extract has not yet been evaluated for potential therapeutic effect, for example, wound healing. The aim of the study was to elucidate the in vitro antioxidant and wound-healing effect of C hystrix peel water extract (CHPWE) and identify the mechanism of CHPWE related to wound-healing activity. Methods: HaCaT keratinocytes were treated with CHPWE and the in vitro wound healing was detected by sulforhodamine B, dsDNA assay, and scratch wound healing test. Filopodia formation was determined by phalloidin-rhodamine staining. The molecular mechanisms related to wound healing were evaluated by western blot analysis. Phytochemical analysis and their in vitro antioxidant were also determined. Results: CHPWE has a high content of phenolic, flavonoid, carotenoid, and anthocyanin content which might be related to a high antioxidant activity. The results demonstrated that high concentration of CHPWE increased keratinocytes proliferation and migration. CHPWE enhanced filopodia development in keratinocytes. Moreover, CHPWE positively controlled FAK, Src, Akt, ERK1/2, and p38, which are signalling molecules required in the regulation of cell proliferation, cell migration, and also wound repair. Conclusions: Our findings point out that CHPWE has a biological potential for recovering cutaneous wound healing.