Antioxidant, anti-tyrosinase, antidiabetic, wound healing, and cytoprotective effects of the aqueous extract of Helichrysum odoratissimum: in vitro, ex vivo, and in silicostudies.

Helichrysum odoratissimum is commonly used in the treatment of diabetes, skin wounds, and eczema. We determined its phytochemical composition and evaluated its antioxidant, anti-tyrosinase, antidiabetic, wound healing, and cytoprotective activities. The antioxidant effect was tested by DPPH, ABTS+, cupric, and ferric methods. The anti-tyrosinase action was determined using tyrosine and L-DOPA as substrates, while the antidiabetic effect was studied by α-amylase and α-glucosidase assays. The cytoprotective activity was studied via cell viability in HaCaT cells, hemolysis using erythrocytes, and HET-CAM assay. Furthermore, drug-likeness, toxicity prediction, and molecular docking of selected phyto-compounds docked against tyrosinase, L-DOPA, α-amylase, and α-glucosidase were studied. H. odoratissimum contained various components of known pharmacological importance such as p-menthone, eucalyptol, palmitic acid, pulegone, and (E)-caryophyllene, and exhibited a strong antioxidant activity. It also inhibited tyrosinase, L-DOPA auto-oxidation, α-amylase and α-glucosidase in a concentration-dependent manner. H. odoratissimum enhanced the migration of keratinocytes and significantly (p<0.05-0.01) increased the percentage of wound closure after 12, 24 and 48 hours of treatment. On the other hand, H. odoratissimum did not cause any cytotoxicity in erythrocytes and hen's egg-chorioallantoic membrane after treatment. All phyto-components from H. odoratissimum met the acceptable standards for drug-likeness and toxicity prediction, according to Lipinski's rule. The strong binding affinity of phyto-components with the active site of proteins recorded in silico supported the in vitro anti-tyrosinase and antidiabetic activities of H. odoratissimum . This plant can be exploited in the development of plant-based anti-tyrosinase, antidiabetic, and wound healing agents. These findings could justify its ethnomedicinal uses.