脂多糖对正常人皮肤成纤维细胞Ⅰ、Ⅲ型前胶原及胶原酶mRNA表达的调控及意义

Regulative effect of lipopolysaccharide on the mRNA expression of procollagen type Ⅰ and type Ⅲ and collagenase of normal human skin fibroblasts and its significance

目的研究细菌脂多糖(LPS)对增生性瘢痕患者正常皮肤成纤维细胞Ⅰ、Ⅲ型前胶原及胶原酶 mRNA 表达的影响,以了解 LPS 在增生性瘢痕形成中的生物学作用。方法体外培养增生性瘢痕患者瘢痕组织及正常皮肤成纤维细胞,应用不同浓度(0.005～1.0μg/ml)的大肠杆菌 LPS(E.coli055:B5)对正常皮肤成纤维细胞进行刺激,并对刺激后细胞传代至表型稳定(第8代),采用逆转录-聚合酶链反应(RT-PCR)法检测 LPS 对正常皮肤成纤维细胞Ⅰ、Ⅲ型前胶原及胶原酶 mRNA 的表达的调控作用,观察剂量-效应关系。分别以同一个体相同代数的瘢痕组织成纤维细胞和未经 LPS刺激的正常皮肤成纤维细胞做阳性对照和阴性对照。结果 LPS 刺激浓度在0.005～0.5μg/ml 范围内促进正常皮肤成纤维细胞Ⅰ、Ⅲ型前胶原 mRNA 表达,抑制胶原酶 mRNA 表达(均 P<0.01),均在0.1μg/ml 浓度点作用达高峰;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,促进胶原酶 mRNA 表达,且均显著低于阴性对照组(均 P<0.01)。当 LPS刺激浓度为0.1μg/ml 时,正常皮肤成纤维细胞Ⅰ、Ⅲ型前胶原 mRNA 和胶原酶 mRNA 表达量与阳性对照组近似(均 P>0.05)。结论在一定浓度范围内 LPS 促进成纤维细胞Ⅰ、Ⅲ型前胶原 mRNA 表达、抑制胶原酶 mRNA 表达。LPS 可能是增生性瘢痕形成的原始诱导因素之一。

Objective To explore the regulative effect of lipopolysaccharide （LPS） on the mRNA expression of procollagen type Ⅰ and type Ⅲ and collagenase of normal skin fibroblasts of hypertrophic scar patients and its biological role in the formation of hypertrophic scar. Methods Scar tissue and normal skin were obtained from 20 patients with hypertrophic scar. Fibroblasts were isolated, underwent passaged culture, and exposed to LPS from Eseheriehia coil of the concentrations of （0. 005 - 1.0 ） μg/ml till they reached stable phenotype（ at the eighth passage ）. The expression of procollagen type Ⅰ and type Ⅲ and collagenase mRNAs were tested by RT-PCR. Fibroblasts from hypertrophic scar tissue obtained from the same patients and normal skin fibroblasts without stimulation of LPS in the same culture passage were used as positive control and negative control respectively. Results When LPS was of the concentrations of 0.005 - 0.5 μg/ml, the mRNA expression levels of procollagen type Ⅰ and type Ⅲ were markedly increased, but the mRNA expression of collagenase was significantly decreased, compared with negative control group（ all P 〈 0.01 ）. The effect reached the peak when the LPS concentration was 0.1 μg/ml. When the concentration of LPS reached 1.0 μg/ml, the mRNA expression levels of procollagen type Ⅰ and type Ⅲ were inhibited and the mRNA expression level of collagenase began to increase, but still lower than that of the negative control group （ P 〈 0. 01 ）. When the concentration of LPS was 0. μg/ml, the mRNA expression levels of procollagen type Ⅰand type Ⅲ and collagenase were similar to that of the positive control group （ all P 〉 0. 05）. Conclusion LPS enhances the mRNA expression of procollagen type Ⅰ and type Ⅲ, inhibits the mRNA expression of collagenase within certain range of concentrations. LPS may be a primitive factor in hypertrophic scar formation.