Protective effect of kudzu root vinegar and adenosine against UVB-induced oxidative stress in human keratinocytes

Ultraviolet (UV) irradiation generates reactive oxygen species (ROS) in cells, which induces sunburn cell formation, melanoma, photoaging, and skin cancer. This study examines the anti-photodamage effects of kudzu root vinegar and adenosine in UVB-exposed human keratinocytes (HaCaT cells). UVB significantly decreased HaCaT cell viability, whereas kudzu root vinegar and adenosine did not exhibit cytotoxic effects and increased the viability of HaCaT cells. To investigate the protective effects of kudzu root vinegar and adenosine on UVB-induced oxidative stress in HaCaT cells, ROS, matrix metalloproteinases (MMPs), and mitogen-activated protein kinase (MAPK) were analyzed. UVB-induced treatment reduced the activity of antioxidant enzymes; however, kudzu root vinegar and adenosine increased their activity. These results indicated that kudzu root vinegar and adenosine exert cytoprotective activity against UVB-induced oxidative stress in HaCaT cells. Moreover, they suppressed the UVB-induced downregulation of MMPs and inhibited the phosphorylation of MAPK induced by UVB-irradiation. Therefore, kudzu root vinegar and adenosine offer anti-oxidative effects, via lowering ROS production, suppressing JNK activation, and downregulating expression of MMPs. Our findings suggest that kudzu root vinegar and adenosine have potential application in preventing skin damage owing to UVB exposure. Keywords: reactive oxygen species (ROS), HaCaT cell, UVB, skin damage, anti-aging

Effects of Black Vinegar and Niacinamide on LPS-Induced Inflammation on Human Keratinocytes

In this study, the effects of black vinegar (BA) and niacinamide on lipopolysaccharide (LPS)-treated human keratinocytes, HaCaT cells, were investigated. First of all, BA and niacinamide have no cytotoxicity in HaCaT cells even at high concentrations. LPS treatment triggers the phosphorylation of p38 mitogen-activated protein kinases (MAPK) and the expression of inflammatory enzymes, iNOS and COX-2. In contrast, BA and niacinamide weakened the expression of LPS-induced COX-2 and iNOS. Based on the results, we concluded that BA and niacinamide have effective anti-inflammatory properties in HaCaT cells. Therefore, BA and niacinamide may be used as new alternative treatments for inflammatory skin diseases. Keywords: Black vinegar, HaCaT cell, Inflammation, Keratinocytes, Liposaccharides, Niacinamide