» Articles » PMID: 38183537

Rapamycin Protects Mouse Skin from Ultraviolet B-induced Photodamage by Modulating Hspb2-mediated Autophagy and Apoptosis

Overview
Journal Mol Biol Rep
Specialty Molecular Biology
Date 2024 Jan 6
PMID 38183537
Authors
Affiliations
Soon will be listed here.
Abstract

Background: Continuous exposure to UVB is the main extrinsic cause of skin photodamage, which is associated with oxidative stress, DNA damage, apoptosis and degradation of collagen. Rapamycin, a mechanistic target inhibitor of rapamycin complex 1 (mTORC1), has been shown to play a crucial role anti-tumor and aging retardation, but its mechanism of action in UVB-induced photodamage still remains unknown. In this study, we investigated the role of rapamycin and Hspb2 (also known as Hsp27) in UVB-induced photodamage in mice.

Methods And Results: We constructed skin acute photodamage models on the ears of WT and Hspb2 KO mice, respectively, and administered rapamycin treatment. Histological results showed that knockout of the hspb2 exacerbated the skin damage, as evidenced by thickening of the epidermis, breakage and disruption of collagen fibers and reduction in their number, which is reversed by rapamycin treatment. In addition, hspb2 knockout promoted UVB-induced apoptosis and reduced autophagy levels, with a significant increase in p53 levels and Bax/Bcl-2 ratio, a reduction in LC3II/I ratio and an increase in p62 levels in the KO mice compared to those in WT mice after the same dose of UVB irradiation. Rapamycin was also found to inhibit collagen degradation induced by hspb2 knockdown through activation of the TGF-β/Smad signaling pathway.

Conclusions: Rapamycin can alleviate skin photodamage from Hspb2 knockout to some extent. It may be a potential therapeutic drug for skin photodamage. In this study, we investigated the role of rapamycin and Hspb2 in UVB-induced photodamage in mice. Histological results showed that knockout of the hspb2 exacerbated the skin damage, as evidenced by thickening of the epidermis, breakage and disruption of collagen fibers and reduction in their number, which is reversed by rapamycin treatment. In addition, hspb2 knockout promoted UVB-induced apoptosis and reduced autophagy levels. Rapamycin was also found to inhibit collagen degradation induced by hspb2 knockdown through activation of the TGF-β/Smad signaling pathway. We conclude that rapamycin and Hspb2 exert a synergistic protective effect in skin photodamage.

References
1.
Chambers E, Vukmanovic-Stejic M . Skin barrier immunity and ageing. Immunology. 2019; 160(2):116-125. PMC: 7218662. DOI: 10.1111/imm.13152. View

2.
Hart P, Norval M, Byrne S, Rhodes L . Exposure to Ultraviolet Radiation in the Modulation of Human Diseases. Annu Rev Pathol. 2018; 14:55-81. DOI: 10.1146/annurev-pathmechdis-012418-012809. View

3.
Rojo de la Vega M, Zhang D, Wondrak G . Topical Bixin Confers NRF2-Dependent Protection Against Photodamage and Hair Graying in Mouse Skin. Front Pharmacol. 2018; 9:287. PMC: 5880955. DOI: 10.3389/fphar.2018.00287. View

4.
Matsumura Y, Ananthaswamy H . Toxic effects of ultraviolet radiation on the skin. Toxicol Appl Pharmacol. 2004; 195(3):298-308. DOI: 10.1016/j.taap.2003.08.019. View

5.
Sun Z, Park S, Hwang E, Zhang M, Jin F, Zhang B . Salvianolic Acid B Protects Normal Human Dermal Fibroblasts Against Ultraviolet B Irradiation-Induced Photoaging Through Mitogen-Activated Protein Kinase and Activator Protein-1 Pathways. Photochem Photobiol. 2015; 91(4):879-86. DOI: 10.1111/php.12427. View