MAPK/AP-1 Signaling Pathway Is Involved in the Protection Mechanism of Bone Marrow Mesenchymal Stem Cells-Derived Exosomes against Ultraviolet-Induced Photoaging in Human Dermal Fibroblasts.

INTRODUCTION: The role of bone marrow mesenchymal stem cells-derived exosomes (BMSCs-exo) in skin photoaging was explored in human dermal fibroblasts (HDFs). The underlying mechanism was further explored. METHODS: HDFs were exposed to UVB irradiation to establish the cell photodamage models. The cell viability and levels of oxidative stress-related factors were tested. ELISA was done to detect TNF-α, IL-6, and IL-1ß concentrations. Western blot was applied for protein examination. RESULTS: UVB treatment led to the inhibition of cell viability. But after BMSCs-exo addition, the inhibitory effect was returned in a dose manner. UVB exposure contributed to the increase of reactive oxygen species and LDH and the downregulation of superoxide dismutase. In addition, excessive secretion of TNF-α, IL-6, and IL-1ß was also detected in cells exposed to UVB. However, BMSCs-exo addition eliminated the effects of UVB on oxidative stress and inflammation in HDFs. BMSCs-exo inhibited matrix metalloproteinases MMP-1 and MMP-3 expression but promoted collagen I expression. UVB radiation activated the MAPK/AP-1 signaling, manifested as the increase of p-p38, c-Jun, and c-Fos protein levels, which were reversed by BMSCs-exo. As a p38 agonist, anisomycin counteracted the effect of BMSCs-exo on HDF's viability, oxidative stress, and inflammation. CONCLUSION: BMSCs-exo protected HDFs against UVB-induced inhibition of cell viability and the activation of cell oxidative stress and inflammation, which might be related to the inhibition of the MAPK/AP-1 signaling pathway.

Bone marrow mesenchymal stem cell-derived exosome miR-29b-3p alleviates UV irradiation-induced photoaging in skin fibroblast.

BACKGROUND: Mesenchymal stem cells-derived exosome (MSCs-exo) was identified to reduce photoaging. The purpose of this study was to investigate the potential role of microRNA (miR)-29b-3p derived from bone marrow MSCs-exo (BMSCs-exo) in photoaging. METHODS: Exosomes were isolated from BMSCs and verified by Western blot. A photoaging cell model was constructed by UVB irradiation of human dermal fibroblasts (HDFs). Quantitative real-time PCR (RT-qPCR) was performed to detect the mRNA levels of miR-29b-3p, collagen type I and matrix metalloproteinases (MMPs). CCK-8, Transwell and flow cytometry were applicated to examine cell viability, migration and apoptosis. Commercial kits are used to measure levels of oxidative stress indicators. Finally, a dual-luciferase reporter assay was applied to validate the target of miR-29b-3p. RESULTS: Extracted exosomes were positive for HSP70 and CD9. Survival of HDFs increased in an exosome concentration-dependent manner. UVB irradiation inhibited miR-29b-3p levels compared with controls, but BMSCs-exo treatment restored miR-29b-3p levels (p < .05). Additionally, BMSCs-exo-miR-29b-3p reversed the inhibition of HDFs migration and oxidative stress by UVB irradiation, as well as the promotion of apoptosis. However, this reversal was attenuated by the suppression of miR-29b-3p (p < .05). Furthermore, BMSCs-exo-miR-29b-3p also inhibited the degradation of collagen type I and the production of MMPs in photoaging, and they were also eliminated by the reduced miR-29b-3p. Finally, MMP-2 was the target gene of miR-29b-3p. CONCLUSION: Our study presented a novel role for BMSCs-exo-miR-29b-3p in improving skin photoaging function, and these findings may provide new insights into the targeted treatment of skin photoaging.

Chemical peeling with 35% glycolic acid for the treatment of disseminated facial verruca plana: A randomized, split-face, evaluator-blinded trial.

Disseminated facial verruca plana is a chronic disorder that causes significant psychological distress. However, safe and effective treatment is lacking. This study aimed to explore the efficacy and safety of 35% glycolic acid (GA) for the treatment of disseminated facial verruca plana. A split-face clinical trial was conducted to explore the efficacy and safety of using chemical peeling with 35% GA for the treatment of disseminated facial verruca plana. One side of the face was applied with 35% GA once every fortnight for a total of three times. Adapalene gel was applied every night to the other side of the face as the control. The clearance rate of lesions was evaluated at different time points. Between June 2020 and December 2020, 30 patients with disseminated verruca plana who visited the Dermatology Hospital of Southern Medical University were enrolled. After three chemical peelings with 35% GA that was applied at 2-week intervals, 15 (50%) patients achieved >70% lesion reduction. The same effective rate in the adapalene gel-treated side of the face was documented in eight patients. Subgroup analysis showed a higher clearance rate in patients with a shorter disease duration. Moreover, concurrent improvements in facial roughness were observed in the 35% GA-treated group. Adverse effects including mild erythema and desquamation were observed during chemical peeling with 35% GA. In conclusion, chemical peeling with 35% GA could be a safe and effective option for treating disseminated facial verruca plana, especially for those who desire skin improvement.