Lipid analysis of cell membranes in normal dermis, hypertrophic and keloidal scars

增生性瘢痕（HS）是异常伤口愈合的结果。HS形成的基本机制仍然是未知的;然而，已经揭示了参与HS形成的许多因素：肥大细胞、TGF-β和培养的成纤维细胞。与正常皮肤相比，HS表现出肥大细胞数量的四倍增加。虽然HS产生过量的胶原蛋白，但来自HS和正常皮肤的成纤维细胞具有相似的增殖速率。来源于HS的成纤维细胞的行为更像来自正常瘢痕的成纤维细胞，而不是来自瘢痕疙瘩的成纤维细胞，因为它们没有表现出对TGF-β的过度反应。一些研究者已经描述了脂质与瘢痕形成和伤口愈合之间的相互作用。我们检查了包含在其中的脂肪酸，并通过膜参与每个反应;然后我们分析了去上皮正常真皮（ND）和HS中脂肪酸的百分比组成。体内HS样品从6名接受手术切除的患者获得，ND样品从5名接受皮肤移植手术的患者获得。在体外，培养的成纤维细胞从HS和ND进行了分析。分析了从所有样品中提取的脂肪酸的百分比组成。在体内，花生四烯酸（20：4）是显着更丰富的HS比ND，在整个组织和细胞膜的磷脂。在体外，ND、HS和10%胎牛血清（FCS）之间无显著差异。结果表明，HS的形成并不一定涉及简单的过量的20：4-酸，但是，有相当大的差异，ND和HS之间的20：4-酸的百分比组成。花生四烯酸可能参与HS的形成和维持，而在体外培养的成纤维细胞的FCS的影响很大。

Hypertrophic scars (HS) are the consequence of abnormal wound healing. The basic mechanism of HS formation is still unknown; however; a number of factors involved in HS formation have been revealed: the mast cells, TGF-beta, and cultured fibroblasts. Compared with normal skin, HS demonstrate four-fold increase in the numbers of mast cells. Although HS produce excess collagen, fibroblasts from HS and normal skin have similar proliferation rates. Fibroblasts derived from HS behave more like those from normal scars than those from keloids by not exhibiting an exaggerated response to TGF-□ We focused on fatty acids involved in HS on the hypothesis that some lipids influence HS formation and maintenance. Several investigators have described the interactions between lipids and scarring and wound healing. We examined fatty acids that are contained within, and participate in every reaction through membrane; then we analyzed the percentage composition of the fatty acids in de-epithelialized normal dermis (ND) and HS. In vivo HS samples were obtained from 6 patients undergoing surgical excision, and ND samples from 5 patients undergoing skin grafting surgery for excess. In vitro, cultured fibroblasts from HS and ND were also analyzed. The percentage composition of fatty acids extracted from all the samples was analyzed. In vivo, arachidonic acid (20:4) was significantly more abundant in HS than in ND, in the phospholipids from both whole tissue and cell membrane. In vitro, there were no significant difference among ND, HS, and 10% fetal calf serum (FCS). The results suggest that HS formation does not necessarily involve simple excess of 20:4-acid; however, there are considerable differences in percentage composition of 20:4-acid between ND and HS. Arachidonic acid probably participates in the formation and maintenance of HS, whereas in vitro cultured fibroblasts are affected largely by FCS.