A novel decorin gene mutation in congenital hereditary stromal dystrophy: a Korean family

A 43-year-old man developed decreased vision in the right eye that had persisted for seven years. Under slit lamp examination, corneal clouding was noted with normal endothelium and ocular structure. From the clinical evidence, we suspected that the patient had congenital hereditary stromal dystrophy (CHSD). He and his family underwent a genetic analysis. Penetrating keratoplasty was conducted, and the corneal button was investigated for histopathologic confirmation via both light and electron microscopy. The histopathologic results revealed mildly loosened stromal structures, which exhibited an almost normal arrangement and differed slightly from the previous findings of CHSD cases. With regard to the genetic aspects, the patient and his mother harbored a novel point mutation of the decorin gene. This genetic mutation is also distinct from previously described deletion mutations of the decorin gene. This case involved delayed penetration of mild clinical symptoms with the histological feature of a loosened fiber arrangement in the corneal stroma. We concluded that this condition was a mild form of CHSD. However, from another perspective, this case could be considered as "decorin gene-associated corneal dystrophy," which is distinct from CHSD. Further evaluation will be required for appropriate clinical, histopathologic and genetic approaches for such cases.     

Different Modulation of Decorin Production by Lung Fibroblasts from Patients with Mild and Severe Emphysema

We have previously reported diminished immunohistochemical staining of decorin in lung tissue from patients with severe emphysema. The aim of this study is to investigate whether this diminished staining is due to a quantitative abnormal production of decorin by pulmonary fibroblasts in vitro. Therefore, we measured decorin (Western blot), collagen type I (ELISA), and fibronectin (ELISA) production by fibroblasts obtained from lung tissue of patients with severe and mild emphysema at basal culture conditions and after modulation with transforming growth factor-β₁, basic fibroblast growth factor, and interferon-γ. Decorin production at basal culture conditions was significantly higher in fibroblast cultures from patients with severe emphysema compared to fibroblasts from mild emphysema. After stimulation with transforming growth factor-β₁ and basic fibroblast growth factor, decorin production was significantly more reduced in fibroblast cultures from patients with severe emphysema whereas collagen type I and fibronectin production were not affected. We conclude that decorin production by lung fibroblasts of patients with severe emphysema is dysregulated after modulation with cytokines known to be important in smoking associated inflammation. This dysregulation of decorin production may contribute to the impaired lung tissue repair, present in patients with emphysema, since these alterations in the extracellular matrix may cause diminished cytokine binding and neutralization.     

Changes of collagen type III and decorin in paraurethral connective tissue from women with stress urinary incontinence and prolapse

Thirteen premenopausal women with stress urinary incontinence (SUI), 6 with SUI and prolapse, 9 with prolapse, and 19 without prolapse were enrolled to observe the content change of collagen type III and the expression of decorin mRNA in paraurethral connective tissues. Collagen type III from transvaginal biopsies was assayed by immunohistochemical staining and decorin mRNA was detected by real-time PCR. Premenopausal women with SUI had a significantly decreased level of collagen type III. Decorin mRNA expression was significantly increased in both premenopausal SUI+prolapse group and premenopausal prolapse group reflected by the decrease of ΔCt value compared to their corresponding controls. The results suggest that a high level of decorin mRNA might be associated with the reduced content of collagen type III, resulting in a less flexible form of extracellular matrix in the connective tissue in SUI and prolapse patients. This study was supported by a grant from the Fujian Science and Technology Bureau Foundation (grant no. 2000I1003).     

Changes in gene expression of individual matrix metalloproteinases differ in response to mechanical unloading of tendon fascicles in explant culture

Immobilization of the tendon and ligament has been shown to result in a rapid and significant decrease in material properties. It has been proposed that tissue degradation leading to tendon rupture or pain in humans may also be linked to mechanical unloading following focal tendon injury. Hence, understanding the remodeling mechanism associated with mechanical unloading has relevance for the human conditions of immobilization (e.g., casting), delayed repair of tendon ruptures, and potentially overuse injuries as well. This is the first study to investigate the time course of gene expression changes associated with tissue harvest and mechanical unloading culture in an explant model. Rat tail tendon fascicles were harvested and placed in culture unloaded for up to 48 h and then evaluated using qRT‐PCR for changes in two anabolic and four catabolic genes at 12 time points. Our data demonstrates that Type I Collagen, Decorin, Cathepsin K, and MMP2 gene expression are relatively insensitive to unloaded culture conditions. However, changes in both MMP3 and MMP13 gene expression are rapid, dramatic, sustained, and changing during at least the first 48 h of unloaded culture. This data will help to further elucidate the mechanism for the loss of mechanical properties associated with mechanical unloading in tendon. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:1306–1312, 2008     

重组人类核心蛋白聚糖对白血病K562细胞增殖的影响

 【摘要】　目的　观察重组人类核心蛋白聚糖（rhDCN）对白血病 K562细胞生长抑制、凋亡的影响,并探讨可能的作用机制。方法　通过Lipofectamine 2000脂质体介导转染对数生长期的白血病K562细胞,实验分组为0.9 % NaCl溶液组、pcDNA3.1（+）／K562组、pcDNA3.1（+）-DCN／K562组和脂质体组。经瑞特染色观察转染后细胞形态的改变,MTT法检测细胞增殖活性,流式细胞术（FCM）分析细胞凋亡,Western blot法检测细胞凋亡相关蛋白bcl-xl、Mcl-1及Bax的表达。结果　pcDNA3.1（+）-DCN／K562组瑞特染色呈现典型的凋亡形态学改变。MTT结果显示,pcDNA3.1（+）-DCN／K562组转染24 h细胞增殖抑制率为（16.14±1.08）%,转染48 h为（14.07±1.01）%,转染72 h为（20.29±1.19）%,明显高于对应时间点其他组增殖抑制率,差异均有统计学意义（均P＜0.05）。FCM检测结果显示,pcDNA3.1（+）-DCN／K562组凋亡率为（20.15±1.31）%、细胞的G0／G1期细胞百分率为（51.15±0.57）%,与其他各组比较增加明显,差异有统计学意义（均P＜0.05）。Western blot结果显示,pcDNA3.1（+）-DCN／K562组与其他各组比较bcl-xl、Mcl-1蛋白表达减低,Bax蛋白表达升高。结论　rhDCN重组质粒可有效抑制K562细胞增殖,并诱导其凋亡,rhDCN对细胞周期及凋亡相关蛋白bcl-xl、Mcl-1、Bax的影响可能是其发挥作用的机制。     

Serum decorin measurement in prediction of the risk for preterm birth

Objective

To define serum decorin (sDEC) levels in healthy pregnants and in patients with preterm labor (PTL), and to introduce possible role of sDEC in predicting the risk for preterm birth (PTB).

Decorin和Ⅰ型、Ⅲ型胶原纤维在牙周损伤愈合中的免疫化学定位和表达

目的:研究decorin和Ⅰ型、Ⅲ型胶原纤维在牙周组织损伤愈合过程中的免疫化学定位.方法:损伤成年鼠磨牙周围的牙周组织,跟踪28 d,对decorin 和Ⅰ型、Ⅲ型胶原在愈合过程中的免疫组织化学分布进行分析.结果:decorin在结缔组织中的免疫组织化学分布与Ⅰ型胶原相似.Ⅲ型胶原分布较散在.在牙周损伤愈合早期,decorin与损伤区周围的成纤维细胞关系密切,特别是牙龈黏膜的固有层,成纤维细胞对decorin的表达非常强.愈合中期,decorin广泛表达于肉芽组织成纤维细胞.愈合晚期,decorin的免疫阳性表达主要位于损伤区周围的上皮下区域.结论:decorin在牙周组织损伤区中的细胞内特征性表达,预示其与胶原纤维相互作用,在牙周损伤愈合过程中起着不可忽视的作用.     

核心蛋白聚糖在肝纤维化形成中的作用

背景：肝纤维化可进展为肝硬化,并破坏肝脏正常结构,从而导致肝功能异常和不可逆肝硬化。本研究以四氯化碳小鼠肝纤维化模型为研究对象,观察外源性核心蛋白聚糖对纤维化形成是否有缓解作用。 方法：5周龄Balb/c小鼠,腹腔注射CCl4 5周建立肝纤维化模型,注射剂量为1ml/kg (CCl4体积:橄榄油体积=1:1),每2天注射1次。检测肝标本中肝纤维化相关分子表达情况。 腹腔注射CCl4三周后,将存活纤维化小鼠随机分为2组（每组6只）,实验组（DCN组）以及纤维化对照组。同时建立5周正常对照组（6只）。每天两次予实验组注入250ug/kg核心蛋白聚糖DCN,对照组注射等量的（PBS NS）溶液。DCN注射2周后,取下三组肝脏标本。取下方叶并将其分成两部分：一部分切成多个小块用于提取组织RNA,检测相关基因表达情况;另外一部分放入福尔马林中用于HE染色、Masson染色以及免疫组化检测相关指标。 结果：外源性小鼠DCN蛋白可缓解四氯化碳诱导的肝纤维化。实验组较对照组肝纤维化程度明显减轻,胶原纤维量明显低于对照组。 结论：本部分实验以小鼠肝纤维化模型为实验对象,自3周开始向实验组注射DCN蛋白,结果表明外源性DCN可以抑制纤维化相关分子的表达,缓解肝纤维化形成。     

重组人源白细胞介素-24联合重组人源核心蛋白聚糖对人类肝细胞癌HepG2细胞增殖抑制和凋亡诱导协同效应的研究

目的 观察外源基因重组人源白细胞介素（IL）-24（rhIL-24）联合重组人源核心蛋白聚糖（rhDCN）对人类肝细胞癌HepG2细胞的增殖、凋亡和细胞周期的影响.方法 采用脂质体瞬时转染法将pcDNA3.1（＋）-IL-24和pcDNA3.1（＋）-DCN质粒转染至HepG2细胞,48 h后倒置显微镜下观察细胞生长状况、形态学改变.分别在转染后24h、48 h和72 h,采用四甲基偶氮唑蓝（MTT）法观察IL-24和DCN单独及联合转染对HepG2细胞的增殖抑制效应.转染后48 h流式细胞术检测HepG2细胞凋亡情况,并进行细胞周期阻滞分析.结果 与对照组相比,转染目的基因48 h后显微镜下可见细胞生长不同程度地被抑制,并可见典型的凋亡细胞形态改变,以联合转染组改变更为明显.MTT结果显示转染后48 h和72 h,双基因联合转染组的抑制率分别是（31.88±6.57）％和（36.83±3.76）％,与对照组和单独转染组比较,差异均有统计学意义（P＜0.01）.流式细胞术结果显示,单独转染IL-24和DCN基因可诱导HepG2细胞出现不同程度凋亡,而双基因联合转染组细胞凋亡率可达（32.56±0.90）％,与空质粒转染组的（2.98±0.72）％、空白细胞对照组的（3.50±0.92）％、IL-24组的（20.01±1.08）％和DCN组的（22.20±0.91）％比较,差异均有统计学意义（P＜0.01）.细胞周期分析结果表明,与对照组相比,IL-24基因转染组的G2/M期和DCN基因转染组的G0/G1期细胞比例明显增高分别为（11.24±0.35）％、（77.93±0.67）％,而双基因联合转染组G0/G1期和G2/M期细胞比例同时增高,分别是（71.36±0.60）％和（10.39±0.67）％,差异有统计学意义（P＜0.01）.结论 联合转染IL-24和DCN基因可以协同发挥较单独应用更强的抑制HepG2细胞增殖和诱导HepG2细胞凋亡的作用.IL-24可使HepG2细胞发生G2/M期阻滞,DCN可使HepG2细胞发生G0/G1期阻滞,双基因联合使HepG2细胞同时发生G2/M期和G0/G1期阻滞,是IL-24和DCN对HepG2细     

DCN的研究进展

核心蛋白聚糖（decorin,DCN）是一种与胶原纤维相关的蛋白聚糖,广泛存在于细胞外基质中。DCN可通过多种途经发挥抗纤维化、抗肿瘤等作用,DCN在这些领域的研究应用已成为热点。近年来对DCN作用的研究取得了重大的进展,现作一综述。