脂多糖对人皮肤成纤维细胞胶原代谢的影响

Influence of lipopolysaccharide on collagen metabolism of normal skin fibroblasts of human

目的探讨脂多糖（1ipopolysaccharide，LPS）对人皮肤成纤维细胞胶原代谢的影响，以了解LPS在增生性瘢痕形成中的生物学作用。方法取正常皮肤行成纤维细胞培养后，分为1个对照组及6个实验组。实验组分别与终浓度为0．005、0．010、0．050、0．100、0．500和1．000μg／ml大肠杆菌LPS（Ecoli055：B5）培养，对照组DMEM培养。用逆转录-聚合酶链反应（RT-PCR）法测定成纤维细胞Ⅰ、Ⅲ型前胶原mRNA及胶原酶mRNA的表达，并以同一个体相同代数的瘢痕组织成纤维细胞做对照。结果与对照组比较，LPS刺激浓度在0．005-0．1μg／ml时，促进正常皮肤成纤维细胞Ⅰ、Ⅲ型前胶原mRNA表达（0．323±0．041，0．303±0．063，0．391±0．071，0．344±0．086，0．488±0．059，0．401±0．087，0．616±0．107，0．434±0．084，0．823±0．092，0．542±0．082），抑制胶原酶mR-NA表达（0．598±0．068，0．556±0．049，0．441±0．043，0．372±0．083，0．260±0．027），且呈一定的剂量依赖性；当LPS刺激浓度为0．5μ／ml，上述作用下降（0．451±0．063，0．374±0．072，0．360±0．062）；而当LPS刺激浓度到达1．0μg/ml时，抑制正常皮肤成纤维细胞Ⅰ、Ⅲ型前胶原mRNA表达（0．162±0．025，0．171±0．061），促进胶原酶mRNA表达（0．444±0．114）。LPS刺激浓度在0．1μg／ml时，成纤维细胞（0．823±0．092，0．542±0．082，0．260±0．027）Ⅰ、Ⅲ型前胶原mRNA和胶原酶mRNA表达与同一个体增生性瘢痕组织成纤维细胞（0．829±0．049，0．569±0．038，0．277±0．059）近似。结论LPS对人皮肤成纤维细胞Ⅰ、Ⅲ型前胶原mRNA和胶原酶mRNA的表达，其直接调节可能是参与增生性瘢痕形成的重要机制。

Objective To observe the influence of lipopolysaccharide （LPS） on collagen metabolism of normal human skin fibroblasts and its biological role in the formation of hypertrophic scar. Methods Fibroblasts were isolated and cultured in vitro, and then exposed to different doses of LPS （0.005、0.01、0.05、0.1、0.5,1.0μg/ml） fromE, coli. 055：B5 respectively. The expression of procellagen type Ⅰ , Ⅲand collagenase mRNAs was tested by RT - PCR. Fibroblasts from hypertrophic scar tissue obtained from the same patients in the same culture passage were used as control. Results Compared with control group, the expression of procollagen type Ⅰ , Ⅲ mRNAs in normal skin fibroblasts increased （0.323±0.041,0.303±0.063,0.391±0.071,0.344±0.086,0.488±0.059,0.401±0.087,0.616±0.107,0.434±0.084,0.823±0.092,0.542±0.082） ）, while the expression of collagenase mRNAs of normal skin fibro-blasts depressed（0.598±0.068,0.556±0.049,0.441±0.043,0.372±0.083,0.260±0.027 ）. When LPS was set to the concentration of 0. 005 μg/ml, it showed a concentration dependent manner. However, when the concentration of LPS was set to 0. 5μg/ml, the expression of procollagen type Ⅰ、Ⅲ and collage- nase mRNAs of normal skin fibmblasts began to decrease （0.451±0.063,0.374±0.072,0.360±0.062）. When the concentration of LPS was set to 1.0 μg/ml, the expression of procollagen typeⅠ、Ⅲ mRNAs （0.162±0.025,0.171±0.061 ）were inhibited and the expression of collagenase mRNAs bezan to increase（0. 444±0. 114）. When the concentration of LPS was set to 0. 1 μg/ml, the expression of procollagen type Ⅰ,Ⅲand collagenase mRNAs of normal skin fibroblasts（0.823±0.092,0.542±0.082,0.260±0.027） was similar to that of hypertrophic scar tissue fibroblasts （0.829±0.049,0.569±0.038,0.277±0.059）. Conclusions This result supported that LPS may be an important factor in collagen metabolism of normal skin fibroblasts and it plays an important role in hypertrophic scar formation.