海洋胶原肽对SD大鼠自然衰老皮肤胶原合成的促进作用研究

目的 观察海洋胶原肽(MCP)长期喂养对SD大鼠自然衰老皮肤的胶原合成的影响.方法 4周龄雄性SD大鼠按体重随机分入对照组和海洋胶原肽低、中、高3个剂量干预组,分别在基础饲料中添加0％、2.25％、4.5％和9％ (wt/wt)的MCP喂养24月后取其脊柱两侧皮肤组织.结果 经过MCP长期干预,免疫组织化学实验结果表明皮肤组织Ⅰ型与Ⅲ型胶原蛋白的表达水平较老年对照组明显增加；MCP 3个剂量组的Ⅰ型和Ⅲ型前胶原基因COL1A2和COL3A1的表达水平均比老年对照组有显著升高(P＜0.05)；与老年对照组相比,MCP干预组TβRⅡ蛋白的表达水平及磷酸化Smad2/Smad2的比例显著升高,而Smad7的表达水平则有一定程度的下降(P＜0.05).结论 本研究表明MCP长期干预对于SD大鼠自然衰老皮肤的胶原合成具有一定的促进作用,其机制可能与上调TβRⅡ蛋白表达水平而激活Smad蛋白信号通路而促进胶原蛋白表达有关.

The oral administration of marine collagen peptides promoting collagen synthesis in the chronological aged skin of Sprague-Dawley rats

OBJECTIVE The aim of the study was to investigate the effect of long-term oral administration of marine collagen peptides on the collagen synthesis in the chronological aged skin.METHODS Sprague-Dawley male rats of 4-week-old were administrated with MCP at the diet concentrations of 0%,2.25%,4.5%,and 9% for 24 months.After being sacri?ced,full thickness skin samples were excised from the depilated dorsal regions.RESULTS Immuno-histological analysis showed that MCP had the potential to promote the expression of typeⅠand Ⅲ collagen in chronological aged skin.Furthermore,quantitative real-time polymerase chain reaction revealed MCP was able to promote the expressions of procollagen type Ⅰ and Ⅲ mRNA(COL1A2 and COL3A1)(P﹤0.05).Meanwhile,as compared with the aged control group,western blot analysis indicated the expression level of TGF-βRⅡ and ratio of phosphorylated Smad2 were up-regulated in the MCP-treated groups,whereas the expression level of Smad7 markedly decreased in the MCP-treated groups(P﹤0.05).CONCLUSION MCP is demonstrated to have the potential to promote collagen synthesis in the chronological aged skin of Sprague-Dawley male rats with the possible mechanism of activating TGF-β/Smad signaling pathway.