It was previously demonstrated that the methanol fraction of Sideroxylon obtusifolium (MFSOL) promoted anti-inflammatory and healing activity in excisional wounds. Thus, the present work investigated the healing effects of MFSOL on human keratinocyte cells (HaCaT) and experimental burn model injuries. HaCaT cells were used to study MFSOL's effect on cell migration and proliferation rates. Female Swiss mice were subjected to a second-degree superficial burn protocol and divided into four treatment groups: Vehicle, 1.0% silver sulfadiazine, and 0.5 or 1.0% MFSOL Cream (CrMFSOL). Samples were collected to quantify the inflammatory mediators, and histological analyses were performed after 3, 7, and 14 days. The results showed that MFSOL (50 μg/mL) stimulated HaCaT cells by increasing proliferation and migration rates. Moreover, 0.5% CrMFSOL attenuated myeloperoxidase (MPO) activity and also stimulated the release of interleukin (IL)-1β and IL-10 after 3 days of treatment. CrMFSOL (0.5%) also enhanced wound contraction, promoted improvement of tissue remodeling, and increased collagen production after 7 days and VEGF release after 14 days. Therefore, MFSOL stimulated human keratinocyte (HaCaT) cells and improved wound healing via modulation of inflammatory mediators of burn injuries.

Background: Calotropis procera is a laticiferous plant (Apocynaceae) found in tropical regions all over the world. The ultrastructural characteristics of laticifers, their restricted distribution among different taxonomic groups and in some species in each clade, as peptidases from latex, make them very attractive for biological analysis. Objective: To investigate the effects of LP-PII-IAA (laticifer protein (LP) sub-fraction II (PII) of C. procera presenting an iodoacetamide-inhibited cysteine proteinase activity) on irinotecan-induced intestinal mucositis, a serious adverse effect of this medicine for the treatment of cancer. Results: LP-PII-IAA is composed of closely related isoforms (90%) of peptidases deprived from catalysis and an osmotin protein (5%). Animals receiving co-administration of LP-PII-IAA presented a significant decrease in mortality, absence of diarrhea, histological preservation and normalization of intestinal functions. Clinical homeostasis was accompanied by a reduction in MPO activity and declined levels of IL-1β, IL-6 and KC while IL-10 level increased in LP-PII-IAA-treated animals. COX-2 and NF-kB immunostaining was reduced and the level of oxidative markers (GSH, MDA) were normalized in animals that received LP-PII-IAA. Conclusion: We suggest that peptidases from the latex of Calotropis procera were instrumental for the suppression of the adverse clinical and physiological effects of irinotecan.