Wound Healing Activity of a Novel Formulation SKRIN via Induction of Cell Cycle Progression and Inhibition of PCNA–p21 Complex Interaction Leading to Cell Survival and Proliferation

The process of wound healing is a dynamic event that starts with inflammation, proliferation, and cell migration of various types of fibroblast cells. Therefore, identification of potential molecules which may increase the wound healing capacity of fibroblast cells is crucial. A novel hydroalcoholic formulation of belladonna (SKRIN), was developed and characterized by GC-MS/MS, DLS, TEM, and AFM and was found to contain atropine and scopolamine exhibit in aggregated nanosized particles. SKRIN-mediated fibroblast cell survival was elucidated in the presence of H2O2 by MTT and flow cytometry based assays. With an EC50 of 4.41 μg/mL, SKRIN treatment showed significant increase in cell survival that was evident from a 1.11-fold increase (p < 0.0122) in the live cell population and 4.21-fold (p < 0.0001) and 2.59-fold (p < 0.0001) reductions in the early and late apoptotic cell populations, respectively. SKRIN-mediated wound healing was measured by cell scratch assay and cell cycle analysis. During the wound closure phenomenon, SKRIN increases repairing fibroblast cell proliferation by 1.24-fold (p = 0.0481) and increases the count of G2/M phase cells by 1.76-fold (p = 0.0002) which was confirmed by increased PCNA and reduced p21 protein expressions probably mediated by molecular interactions of PCNA–p21 complex with alkaloids present in SKRIN. Relative gene expression analysis further showed that SKRIN increases the PI3K, Akt, and NF-κB expression. Our data suggests that SKRIN exhibits wound healing property by increasing cell survival and repairing fibroblast proliferation via activation of the PI3K–Akt–NF-κB pathway probably mediated by inhibition of PCNA–p21 complex interaction.