Overexposure to ultraviolet B (UVB) irradiation induces photoaging that is characterized by the formation of wrinkles and loss of skin elasticity. To understand the mechanism of action of probiotics and prebiotics in skin protection against photoaging, we investigated the effects of dietary supplementation with the probiotic, Bifidobacterium longum, and prebiotic, galacto-oligosaccharide, on UVB-induced photoaging in hairless mice. We measured short chain fatty acid (SCFA) levels, antioxidant enzyme activity, and inflammatory signaling protein levels to elucidate the possible mechanisms underlying the effects of the dietary supplements B. longum and galacto-oligosaccharide. We observed that dietary supplementation with B. longum and galacto-oligosaccharide, individually and in combination, exerted protective effects against UVB-induced photoaging, showing anti-inflammatory and antioxidative effects. In particular, supplementation with the combination of B. longum and galacto-oligosaccharide showed stronger protective effects than supplementation with the probiotic or prebiotic alone. In addition, the serum levels of SCFAs and acetate were increased following dietary supplementation with B. longum and galacto-oligosaccharide, especially in combination. Therefore, we suggest that the combination of B. longum and galacto-oligosaccharide may potentially be used as a functional food to protect UVB-induced photoaging.
Keywords: Bifidobacterium longum; SCFA; UVB; galacto-oligosaccharide; photoaging.