Lactic acid bacteria and their lysate ameliorate skin inflammation in a UVB irradiation-induced skin photoaging mouse model

Skin photoaging is premature skin aging caused by over exposure to ultraviolet (UV) radiation. Photoaged skin is characterized by epidermal thickening, dryness, deep wrinkles, loss of elasticity, delayed wound healing and susceptibility to cancer and closely related to skin inflammation. Meanwhile, it had been reported that lactic acid bacteria (LAB) lysate has lots of beneficial components such as fatty acid, vitamin B, and amino acids, and LAB has the anti-inflammatory effects and the potentials as therapeutics for many chronic inflammatory diseases. Because skin photoaging is recovered by reducing inflammation, co-treatment of LAB and their lysate may alleviate the skin conditions caused by UV-induced skin photoaging via the anti-inflammatory effects. Therefore, the aim of this study is to find out whether co-treatment of LAB and their lysate has beneficial effects on skin conditions and ameliorates skin photoaging. LAB and their lysate were treated in vitro and in vivo. LAB lysate decreased the expression levels of pro-inflammatory cytokines including TNF-α and other inflammation-related biomarkers such as cyclooxygenase 2 (COX-2) and toll-like receptor 4 (TLR4) significantly in HaCaT, the human keratinocyte cell line. LAB and their lysate was evaluated in UVB-induced skin photoaged HR-1 mice model, and it decreased the pro-inflammatory cytokines including TNF-α in serum. LAB and their lysate also decreased pro-inflammatory cytokines in skin, colon, and spleen. Moreover, LAB and their lysate changed the composition of fecal microbiome and short chain fatty acids in mice. In conclusion, the topical treatment of lactic acid bacteria and their lysate may have a potential to ameliorate skin photoaging by reducing inflammation. This work was supported by Korea Testing Laboratory This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.