Kim S B, Kang S A, Cho Y J, Park S K, Cheong H I, Lee J D, Hong C D, Park J S
Department of Internal Medicine, University of Ulsan, Seoul, Korea.
Nephron. 1994;67(3):327-33. doi: 10.1159/000187988.
Hyperlipidemia, especially hypercholesterolemia, may contribute to glomerulosclerosis as it does to atherosclerosis. Low density lipoprotein (LDL) stimulates the production of extracellular matrix by mesangial cells in culture as well as the proliferation of mesangial cells. This study was carried out to examine the effects of LDL on the type IV collagen (CIV) production by cultured rat mesangial cells (CRMC). Subconfluent CRMC monolayers which were grown in RPMI with 20% lipid-free fetal calf serum for 48 h were challenged with LDL (0, 50, 100, 150 and 200 micrograms/ml) for another 48 h. LDL was prepared from normal human plasma. Mesangial cell proliferation was examined by [3H]-thymidine uptake. Production of CIV was evaluated as the expression of CIV on the cell surface by flow-cytometric analysis. The collagen synthesis was measured by the [3H]-proline uptake. Total RNA was extracted from CRMC at 6 and 24 h of incubation with 150 micrograms/ml LDL, and Northern blotting and hybridization was performed with cDNAs for alpha 1-CIV, for 72-kD collagenase and for tissue inhibitor of metalloproteinase (TIMP)-2. The amount of total mRNA was corrected with beta-actin mRNA. Mesangial cell proliferation increased in all concentrations studied and had a peak value of 221% with 150 micrograms/ml of LDL. Expression of CIV increased by 30-60% in 100-200 micrograms/ml of LDL. Collagen synthesis also increased by 50-70% in 150-200 micrograms/ml of LDL. The mRNA ratio (procollagen alpha 1(IV)/beta-actin) increased to 133% at 24 h. The mRNA ratio (TIMP-2/beta-actin) increased to 137% at 24 h. mRNA ratios at 6 h showed no change.(ABSTRACT TRUNCATED AT 250 WORDS)
高脂血症，尤其是高胆固醇血症，可能会导致肾小球硬化，就像它会导致动脉粥样硬化一样。低密度脂蛋白（LDL）可刺激培养的系膜细胞产生细胞外基质以及系膜细胞的增殖。本研究旨在检测LDL对培养的大鼠系膜细胞（CRMC）IV型胶原（CIV）产生的影响。将在含20%无脂胎牛血清的RPMI中生长48小时的亚汇合CRMC单层细胞，再用LDL（0、50、100、150和200微克/毫升）刺激48小时。LDL由正常人血浆制备。通过[3H] - 胸腺嘧啶核苷摄取检测系膜细胞增殖。通过流式细胞术分析评估CIV在细胞表面的表达来评价CIV的产生。通过[3H] - 脯氨酸摄取测量胶原合成。在与150微克/毫升LDL孵育6小时和24小时时从CRMC中提取总RNA，并使用α1 - CIV、72 - kD胶原酶和金属蛋白酶组织抑制剂（TIMP）-2的cDNA进行Northern印迹和杂交。用β - 肌动蛋白mRNA校正总mRNA量。在所研究的所有浓度下系膜细胞增殖均增加，在150微克/毫升LDL时达到峰值221%。在100 - 200微克/毫升LDL中，CIV的表达增加30 - 60%。在150 - 200微克/毫升LDL中，胶原合成也增加50 - 70%。24小时时mRNA比率（前胶原α1(IV)/β - 肌动蛋白）增加到133%。24小时时mRNA比率（TIMP - 2/β - 肌动蛋白）增加到137%。6小时时mRNA比率无变化。（摘要截短于250字）
