Anti-inflammatory and immunomodulatory effects of camel milk exosomes (CM-Exo) in rat models for burn wound healing

Camel milk contains proteins with several beneficial characteristics, such as immune-modulating and anti-oxidant effects. Recent research has shown that these benefits are primarily due to extracellular nanovesicles called exosomes. This study aimed to assess the wound-healing capabilities of camel milk exosomes (CM-Exo).

CM-Exo was extracted, and its size and morphology were examined using DLS, TEM, and SEM. The anti-oxidant properties were assessed using a spectrophotometric (DPPH, FRAP) assay. The MTT test was used to evaluate the viability of human dermal fibroblasts (HDFs) after exposure to high concentrations (HCM-Exo) and low concentrations (LCM-Exo) of milk-Exo. Additionally, a scratch assay analyzed wound closure rate, and the expression of wound healing-associated genes (IL-6 and VEGF-A) was determined using quantitative real-time PCR. We also assessed the healing effects of a topical HCM-Exo ointment on burn-induced rat wounds over 14 days.

DLS, TEM, and SEM analyses showed that CM-Exo had an average size of >100 nm with a characteristic spherical shape. The average anti-oxidant activity, as measured by DPPH and FRAP assays, was higher in the HCM-Exo group compared to the LCM-Exo group. HCM-Exo and LCM-Exo enhanced the viability of HDFs, leading to quicker wound closure in an in vitro model. We found an up-regulation of essential wound healing-related genes (IL-6 and VEGF-A) indicative of an ameliorated healing effect. Evaluation of lesion size and histological data indicated a significant reduction in lesion size in the HCM-Exo and 1% silver sulfadiazine cream (Exo+SS) group compared to both the 1% silver sulfadiazine (SS) group and the negative control (Ctrl) group across days 0, 3, 7, and 14.

Our study concluded that HCM-Exo significantly accelerated wound healing and reduced inflammatory reactions.