Abstract:

In order to explore the influence of inflammatory factors on human skin, inflammatory factor TNF-α was used as a stimulant to act on human skin cells. In this study, TNF-α was used as a stimulant to stimulate human skin cells. The results show that the content of senescence related secretion phenotype, IL-6 and IL-8, in the cells increases, and the cells are under the senescence state. The contents of type I collagen per protein in human skin fibroblasts, which are treated with 20, 100 and 200 ng/mL TNF-α for 24 h, are 2.740, 2.270 and 1.595 mg, respectively, lower than those in the control group; after 4 h of treatment, the contents of MMP-1 per protein are 3.10, 3.12 and 3.10 ng, respectively, higher than those in the control group. At the same time, compared with the control group, the content of intracellular reactive oxygen species is increased, and the balance of intracellular redox system is broken after the keratinocytes exposed to TNF-α. From the above experimental results, the inflammatory factor TNF-α causes the expression of collagen in skin cells abnormal, breaks the redox system, and has a certain effect on accelerating skin aging. Therefore, TNF-α can be used as a stimulant to establish a chronic inflammatory skin aging model. Follow-up experiments established a chronic inflammatory aging model through 200 ng/mL TNF-α, and investigated and compared the inhibitory effects of vitamin C, dragon’s blood extract, and Dendrobium officinale extract on it. The results show that, compared with the control group, 0.1 mg/mL vitamin C, 0.06 mg/mL dragon’s blood, and 0.5 mg/mL Dendrobium officinale extract can effectively promote the synthesis of intracellular collagen, and the contents per unit protein are 4.95, 4.84, 4.08 mg, respectively; can inhibit the expression of MMP-1, and its contents per unit protein are 1.31, 0.84, and 1.26 ng, respectively; can clear the content of reactive oxygen species in the cells and maintain the intracellular redox balance. The results show that vitamin C, as a recognized anti-aging substance, has the same anti-inflammatory aging effect; the extract of Resina draconis and Dendrobium officinale also have certain anti-inflammatory aging effect.

Key words: inflammatory factors, TNF-α, skin ageing, reactive oxygen species