Krill oil (KO) shows promise as a natural marine-derived ingredient for improving skin health. This study investigated its antioxidant, anti-inflammatory, anti-wrinkle, and moisturizing effects on skin cells and UVB-induced skin photoaging in hairless mice. In vitro assays on HDF, HaCaT, and B16/F10 cells, and in vivo experiments on 66 hairless mice, were conducted. Mice received oral KO administration (100, 200, or 400 mg/kg) once a day for 15 weeks and UVB radiation three times a week. In vitro, KO significantly countered UVB-induced oxidative stress, reduced wrinkles, and prevented skin water loss by enhancing collagen and hyaluronic synthesis. In vivo, all KO dosages showed dose-dependent inhibition of oxidative stress-induced inflammatory photoaging-related skin changes. Skin mRNA expressions for hyaluronan synthesis and collagen synthesis genes also increased dose-dependently after KO treatment. Histopathological analysis confirmed that Krill Oil (KO) ameliorated the damage caused by UVB-irradiated skin tissues. These findings suggest that KO may be a valuable intervention to mitigate UVB-induced skin photoaging and address various skin concerns.

Atopic dermatitis (AD) is a chronic and allergic skin disease, however, there is no cure for the disease. Many studies have shown anti-AD potentials of red ginseng, while red ginseng marc (RGM) remained after the ginseng extraction is discarded as industrial waste. However, it is recently reported that RGM, particularly fermented RGM (fRGM), still contains the bioactive properties. Thus, anti-allergic effects of fRGM were examined in 2,4-dinitrochlorobenzene-induced AD-like mice model. The model was topically treated with distilled water (control), dexamethasone, or fRGM for six weeks. The treatments of fRGM alleviated the skin lesions and reduced serum IgE levels, compared with the control. The fRGM also reduced skin levels of lipid peroxidation and superoxide anion, however, increased glutathione contents, with down-regulated gene expressions for inflammatory mediators. The histopathological analyses demonstrated that fRGM suppressed the epidermal thickening, collagen deposition, and inflammatory cell and mast cell infiltration, which involved the anti-inflammatory, anti-oxidant, and anti-apoptotic effects. Further, fRGM suppressed hypertrophic changes and inflammatory responses in the spleen and lymph node. The beneficial effects were observed in the dexamethasone and fRGM groups, however, the antioxidant effects were evident only in the fRGM treatments. These provide useful information for developing fRGM as therapeutic sources for AD.