银耳多糖是银耳中的主要活性物质,具有抗氧化、抗衰老等多种功效。环境中广泛存在的化学污染物苯并[a]芘(BaP)可通过皮肤大量吸收代谢,产生致癌性风险。实验通过体外测定银耳粗多糖抗氧化活性,再通过细胞实验测定BaP与银耳多糖协同作用下成纤维细胞的相关蛋白基因的表达,测定银耳多糖的抗衰老作用。在BaP 暴露条件下,通过qRT-PCR检测不同浓度银耳多糖对胶原蛋白(Collagen I、Collagen III)、弹性蛋白(Elastin)和间质胶原酶(MMP-1)的mRNA表达量的影响,再通过Elisa试剂盒检测Collagen I的蛋白质含量。研究发现,银耳多糖有一定的体外抗氧化活性,在低质量浓度下能有效抑制BaP对细胞胶原蛋白、弹性蛋白及MMP-1基因表达的刺激。Collagen I、Collagen III和Elastin基因表达量呈现多糖浓度依赖性增加。在BaP暴露下,尽管胶原蛋白基因表达量有所增高,但是大量表达的MMP-1降解了胶原蛋白,因此银耳多糖作用下Collagen-1的含量减少,低至3.06μg/L(低于空白对照组3.48μg/L)。说明BaP暴露下低浓度银耳多糖诱导胶原蛋白的降解。
Tremella polysaccharide is the main active substance in Tremella, which has various effects such as anti-oxidation and anti-aging. The widely present chemical contaminant benzo[a]pyrene (BaP) in the environment can be metabolized by large amounts of absorption through the skin, creating a risk of carcinogenicity. The antioxidant activity of Tremella crude polysaccharides was measured in vitro, and the expression of fibroblast-related protein genes under the synergistic action of BaP and Tremella polysaccharides was determined by cell experiments, and the anti-aging effect of Tremella polysaccharides was determined. Under BaP exposure conditions, the effects of different concentrations of Tremella polysaccharides on the mRNA expression of collagen (Collagen I, Collagen III), elastin and interstitial collagenase (MMP-1) were detected by qRT-PCR, and the protein content of Collagen I was detected by Elisa kit. It was found that Tremella polysaccharides had certain antioxidant activity in vitro, and could effectively inhibit the stimulation of cellular collagen, elastin and MMP-1 gene expression by BaP at low mass concentrations. The expression of Collagen I, Collagen III and Elastin genes showed a polysaccharide concentration-dependent increase. Under BaP exposure, although the expression of collagen genes was increased, a large amount of MMP-1 degraded collagen, so the content of Collagen-1 decreased under the action of Tremella polysaccharides to 3.06 μg/L (lower than 3.48 μg/L in the blank control group). This was explained that low concentrations of Tremella polysaccharides induced collagen degradation under BaP exposure.