Photoprotective Effect of Dietary Galacto-Oligosaccharide (GOS) in Hairless Mice via Regulation of the MAPK Signaling Pathway

Abstract

This study investigated the suppression of photoaging by galacto-oligosaccharide (GOS) ingestion following exposure to ultraviolet (UV) radiation. To investigate its photoprotective effects, GOS along with collagen tripeptide (CTP) as a positive control was orally administered to hairless mice under UVB exposure for 8 weeks. The water holding capacity, transepidermal water loss (TEWL), and wrinkle parameters were measured. Additionally, quantitative reverse-transcription polymerase chain reaction and Western blotting were used to determine mRNA expression and protein levels, respectively. The GOS or CTP orally-administered group showed a decreased water holding capacity and increased TEWL compared to those of the control group, which was exposed to UVB (CON) only. In addition, the wrinkle area and mean wrinkle length in the GOS and CTP groups significantly decreased. Skin aging-related genes, matrix metalloproteinase, had significantly different expression levels in the CTP and GOS groups. Additionally, the tissue inhibitor of metalloproteinases and collagen type I gene expression in the CTP and GOS groups significantly increased. Oral administration of GOS and CTP significantly lowered the tissue cytokine (interleukin-6 and -12, and tumor necrosis factor-α) levels. There was a significant difference in UVB-induced phosphorylation of JNK, p38, and ERK between the GOS group and the CON group. Our findings indicate that GOS intake can suppress skin damage caused by UV light and has a UV photoprotective effect.

Inflammatory Molecules Associated with Ultraviolet Radiation-Mediated Skin Aging

“…It has been demonstrated that UVB exposure disrupted the epidermal barrier function in male hairless Balb/c mice in a dose-dependent manner [ 34 , 35 ], and skin barrier disruption can lead to acute inflammatory response or exacerbation of chronic inflammatory skin diseases, such as atopic dermatitis [ 36 ]. Transepidermal water loss (TEWL) is commonly known as a parameter for measuring skin barrier disruption and many reports have confirmed that different UV doses can cause increase of TEWL in murine and human samples [ 37 , 38 , 39 , 40 ]. In epidermis, there are several inflammatory signaling pathways connected to different surface receptors, such as the EGFR [ 41 ], transforming growth factor receptors (TGFR) [ 42 , 43 ], toll-like receptors (TLRs) [ 44 ], IL-1 receptor, and TNF receptor (TNFR) [ 45 , 46 , 47 ].…”

Changes in the Diversity of Human Skin Microbiota to Cosmetic Serum Containing Prebiotics: Results from a Randomized Controlled Trial

“…In our previous study [22,43], GOS were shown to inhibit the production of pro-inflammatory agents IL-6, IL-8, and IL-12; tumor necrosis factor-α; and prostaglandin E2 in UV-irradiated HaCaT cells and hairless mice. The increase in the population of lactic acid bacteria and inhibition of inflammation-producing substances by GOS may have reduced the population of S. aureus and production of pro-inflammatory substances.…”

Changes in The Diversity of Human Skin Microbiota to Cosmetic Serum Containing Prebiotics: Results From A Randomized Controlled Trial

“…In our previous study [17,38], GOS were shown to inhibit the production of pro-in ammatory agents IL-6, IL-8, IL-12, tumor necrosis factor-α and prostaglandin E2 in UV-irradiated HaCaT cells and hairless mice. The increase in the population of lactic acid bacteria and inhibition of in ammation-producing substances by GOS may have reduced the population of S. aureus and production of pro-in ammatory substances.…”