Fornieri C, Quaglino D, Lungarella G, Cavarra E, Tiozzo R, Giro M G, Canciani M, Davidson J M, Ronchetti I P
Department of Biomedical Sciences, University of Modena, Italy.
J Invest Dermatol. 1994 Oct;103(4):583-8. doi: 10.1111/1523-1747.ep12396893.
A case of cutis laxa acquisita was studied with the aim of defining the molecular defects involved and comparing them with those of an inherited form of cutis laxa. In the acquisita form of cutis laxa ultrastructural and biochemical observations confirmed a dramatic reduction of dermal elastin, whereas collagen content was normal. Elastin mRNA expression as well as tropoelastin production by dermal fibroblasts, in vitro, were normal compared with control cells, as revealed by in situ hybridization and enzyme-linked immunosorbent assay, respectively. Lysyl oxidase activity, measured on cultured fibroblasts, was reduced to 60% compared with age-matched control subjects. Unlike control skin fibroblasts or fibroblasts from inherited cutis laxa, the affected skin cells from cutis laxa acquisita predominantly expressed an elastolytic activity identified as cathepsin G. Patient serum also has reduced elastase inhibitory capacity and reduced levels of alpha 1-antiproteinase inhibitor (alpha 1-antitrypsin). Although cutis laxa acquisita is a heterogeneous group of disorders, findings in this patient were consistent with excessive loss of cutaneous elastin due to the combined effects of several factors, such as low lysyl oxidase activity together with high levels of cathepsin G and reduction of circulating proteinase inhibitor(s).
对一例获得性皮肤松弛症进行了研究，目的是确定其中涉及的分子缺陷，并将其与遗传性皮肤松弛症的缺陷进行比较。在获得性皮肤松弛症中，超微结构和生化观察证实真皮弹性蛋白显著减少，而胶原蛋白含量正常。原位杂交和酶联免疫吸附测定分别显示，与对照细胞相比，真皮成纤维细胞的弹性蛋白mRNA表达以及体外原弹性蛋白的产生均正常。与年龄匹配的对照受试者相比，在培养的成纤维细胞上测得的赖氨酰氧化酶活性降低至60%。与对照皮肤成纤维细胞或遗传性皮肤松弛症的成纤维细胞不同，获得性皮肤松弛症患者的受影响皮肤细胞主要表达一种被鉴定为组织蛋白酶G的弹性溶解活性。患者血清的弹性蛋白酶抑制能力也降低，α1-抗蛋白酶抑制剂（α1-抗胰蛋白酶）水平也降低。尽管获得性皮肤松弛症是一组异质性疾病，但该患者的研究结果与多种因素共同作用导致皮肤弹性蛋白过度丢失一致，这些因素包括低水平的赖氨酰氧化酶活性、高水平的组织蛋白酶G以及循环蛋白酶抑制剂的减少。
