Wheat Ceramide Powder Mitigates Ultraviolet B-Induced Oxidative Stress and Photoaging by Inhibiting Collagen Proteolysis and Promoting Collagen Synthesis in Hairless Mice

Abstract

The protective effects of wheat ceramide powder (WC-P) on ultraviolet B (UVB)-induced skin oxidative stress and photoaging in hairless mice were investigated in this study. Moreover, the activities of antioxidant enzymes, inflammation, wrinkle formation-related pathway, and moisturizing capacity were evaluated. Mice were randomly divided into six groups (n=8): normal control (non-UVB irradiation), control (UVB irradiation), L-ascorbic acid [positive control, UVB irradiation with dietary supplementation of L-ascorbic acid at 100 mg/kg/body weight (bw)], WC-P5 (UVB irradiation with dietary supplementation of WC-P at 5 mg/kg/bw), WC-P20 (UVB irradiation with dietary supplementation of WC-P at 20 mg/kg/bw), and WC-P40 (UVB irradiation with dietary supplementation of WC-P at 40 mg/kg/bw). AIN-96G diet and water were supplemented ad libitum, and 100 mL of L-ascorbic acid and WC-P dissolved in water were forcefully administered orally to mice. UVB irradiation resulted in dehydration and wrinkle formation in the dorsal skin of mice. However, WC-P supplementation suppressed. Furthermore, WC-P supplementation enhanced the activites of antioxidant enzymes and expression of transforming growth factor-β receptor I, procollaten C-endopeptideas enhancer protein, hyaluronan synthase, and ceramide synthase 4 and reduced the activation of the inflammation and the c-Jun N-terminal kinase/c-FOS/c-Jun- mediated matrix metalloproteinase pathways. These findings demonstrate that WC-P can protect the skin from UVB-induced oxidative stress, inflammation, and photoaging by inhibiting collagen proteolysis and promoting collagen synthesis, thereby promoting skin health.

Keywords: collagen; skin aging; ultraviolet ray; wheat ceramides.

Fig. 1

High-performance liquid chromatography chromatograms. Standard compound (A), and wheat ceramide powder glucosylceramides (B).

Fig. 2

Effect of wheat ceramide powder (WC-P) on wrinkle formation and skin dryness in ultraviolet B (UVB)-irradiated hairless mice. Morphological and histopathological changes (A), wrinkle area (B), epidermis thickness (C), and skin hydration (D) in the dorsal skin of UVB-irradiated hairless mice. NC, normal control (non-UVB irradiation); C, control (UVB irradiation); PC, positive control [UVB irradiation with dietary supplementation of L-ascorbic acid at 100 mg/kg/body weight (bw)]; WC-P5, UVB irradiation with dietary supplementation of WC-P at 5 mg/kg/bw; WC-P20, UVB irradiation with dietary supplementation of WC-P at 20 mg/kg/bw; WC-P40, UVB irradiation with dietary supplementation of WC-P at 40 mg/kg/bw. Values are presented as the mean±SD. Different letters indicate a significant difference at P<0.05 using Duncan’s multiple range test.

Fig. 3

Effect of WC-P on the activities of superoxide dismutase (A), catalase (B), and glutathione peroxidase (C) in the dorsal skin of UVB-irradiated hairless mice. NC, normal control (non-UVB irradiation); C, control (UVB irradiation); PC, positive control [UVB irradiation with dietary supplementation of L-ascorbic acid at 100 mg/kg/body weight (bw)]; WC-P5, UVB irradiation with dietary supplementation of WC-P at 5 mg/kg/bw; WC-P20, UVB irradiation with dietary supplementation of WC-P at 20 mg/kg/bw; WC-P40, UVB irradiation with dietary supplementation of WC-P at 40 mg/kg/bw. Values are presented as the mean±SD. Different letters indicate a significant difference at P<0.05 using Duncan’s multiple range test.

Fig. 4

Effect of wheat ceramide powder (WC-P) on the mRNA expression of IL-1β (A), IL-6 (B), and tumor necrosis factor-α (TNF-α) (C) and protein expression of IκBα phosphorylation, p65 phosphorylation, and cyclooxygenase-2 (COX-2) (D) in the dorsal skin of ultraviolet B (UVB)-irradiated hairless mice. NC, normal control (non-UVB irradiation); C, control (UVB irradiation); PC, positive control [UVB irradiation with dietary supplementation of L-ascorbic acid at 100 mg/kg/body weight (bw)]; WC-P5, UVB irradiation with dietary supplementation of WC-P at 5 mg/kg/bw; WC-P20, UVB irradiation with dietary supplementation of WC-P at 20 mg/kg/bw; WC-P40, UVB irradiation with dietary supplementation of WC-P at 40 mg/kg/bw. Values are presented as the mean±SD. Different letters indicate a significant difference at P<0.05 using Duncan’s multiple range test.

Fig. 5

Effect of wheat ceramide powder (WC-P) on the protein expression of JNK, c-FOS, c-Jun, MMPs, and Smad3 (A) and mRNA expression of TGF-β RI (B), collagen type I (C), PCOLCE (D), and fibrillin-1 (E) in the dorsal skin of ultraviolet B (UVB)-irradiated hairless mice. NC, normal control (non-UVB irradiation); C, control (UVB irradiation); PC, positive control [UVB irradiation with dietary supplementation of L-ascorbic acid at 100 mg/kg/body weight (bw)]; WC-P5, UVB irradiation with dietary supplementation of WC-P at 5 mg/kg/bw; WC-P20, UVB irradiation with dietary supplementation of WC-P at 20 mg/kg/bw; WC-P40, UVB irradiation with dietary supplementation of WC-P at 40 mg/kg/bw. Values are presented as the mean±SD. Different letters indicate a significant difference at P<0.05 using Duncan’s multiple range test.

Fig. 6

Effect of wheat ceramide powder (WC-P) on the mRNA expression of hyaluronan synthase (HAS) 1 (A), HAS2 (B), and HAS3 (C), protein expression of CerS4 (D), mRNA expression of serine palmitoyltransferase 1 (LCB1) (E), and delta 4-desaturase (DEGS1) (F) in the dorsal skin of ultraviolet B (UVB)-irradiated hairless mice. NC, normal control (non-UVB irradiation); C, control (UVB irradiation); PC, positive control [UVB irradiation with dietary supplementation of L-ascorbic acid at 100 mg/kg/body weight (bw)]; WC-P5, UVB irradiation with dietary supplementation of WC-P at 5 mg/kg/bw; WC-P20, UVB irradiation with dietary supplementation of WC-P at 20 mg/kg/bw; WC-P40, UVB irradiation with dietary supplementation of WC-P at 40 mg/kg/bw. Values are presented as the mean±SD. Different letters indicate a significant difference at P<0.05 using Duncan’s multiple range test.