Effects and interactions of increased environmental temperature and UV radiation on photoageing and photocarcinogenesis of the skin

Abstract

Solar radiation is one of fundamental elements sustaining and maintaining life on earth. Previous studies on health effects from the sun exposure mostly focused on ultraviolet (UV) radiation. Although exposure to the solar radiation likely occurs in an environment with elevated temperature, the effects and interactions of elevated environmental temperature with UV radiation on the skin, especially in the context of ageing and carcinogenesis, have not been carefully examined. It is known that UVA radiation results in reduced production and increased degradation of dermal collagen, contributing to photoageing of the skin. Previous studies showed conflicting results regarding the effects of increased environmental temperature on dermal collagen. Additionally, we demonstrated that solar‐simulated radiation and increased environmental temperature have similar impacts on dermal fibroblasts through activation of distinct pathways. UVB radiation is well known for its carcinogenic capacity. Previously, it was reported that exposure to heat treatment before UVB radiation reduces epidermal keratinocyte cell death. We demonstrated that exposure to elevated environmental temperature prior to UVB radiation reduces UVB‐induced skin tumor formation. We proposed that alterations in molecular dynamics and quantum mechanics were involved for the observed increased environmental temperature‐induced protective effect against UVB damage. This review emphasizes that both environmental temperature and solar radiation are important elements in nature that have significant impacts on the human health, and future studies should focus on the biological effects and interactions of environmental temperature and solar radiation since this scenario is most relevant to the real‐world setting.

http://bit.ly/2Sh5tpk