核心蛋白聚糖Ⅱ过表达对肾组织细胞基质金属蛋白酶2和9表达的影响

目的 观察高水平表达的核心蛋白聚糖Ⅱ(DCN)对高糖培养的大鼠肾组织细胞基质金属蛋白酶2(MMP-2)和基质金属蛋白酶9(MMP-9)表达的影响.方法 用大鼠DCN重组腺病毒载体(Ad/DCN)和抗转化生长因子(TGF)-β1中和抗体分别处理不同糖浓度培养条件下的大鼠肾系膜细胞(RMC)和肾小管细胞(HK-2),用Western印迹法观察转染72 h后DCN蛋白水平变化及其对TGF-β1和Ⅳ型胶原(C-Ⅳ)以及MMP-2和MMP-9表达水平的影响.结果 在RMC细胞中,TGF-β1和C-Ⅳ的蛋内表达在高糖条件下升高(分别为1.63±0.02和0.52±0.01),经抗TGF-β1中和抗体或用Ad/DCN转染处理72 h有明显下降(TGF-β1均下降至0,C-Ⅳ分别为0.29±0.01和0.21±0.01,均P＜0.05);MMP-2和MMP-9在高糖条件下表达下降(分别为0.01±0.00和0.32±0.01),经抗TGF-β1中和抗体或用Ad/DCN转染处理72h有明显上升(MMP-2分别上升至0.65±0.01和0.67±0.01,MMP-9分别上升至0.89±0.01和0.73±0.01,均P＜0.05).而在HK-2细胞中,TGF-β1和C-Ⅳ的蛋白表达在高糖条件下也升高(分别为1.45±0.0l和0.41±0.01),且MMP-2的表达升高(0.27±0.01),经抗TGF-β1中和抗体或用Ad/DCN转染处理72h则有明显下降(TGF-β1分别为0.06±0.01和0.08±0.01,C-Ⅳ分别为0.11±0.01和0.01±0.00,MMP-2分别为0.14±0.01和0.06±0.01,均P＜0.05).结论 高糖对肾小球系膜细胞和小管细胞的基质金属蛋白酶表达的影响是不同的,降低TGF-β1活性可使肾小球系膜细胞和小管细胞基质金属蛋白酶表达转变.

Effects of overexpression of decorin on matrix metalloproteinases 2 and 9 in rat mesangial and tubular cells

Objective To investigate the effects of overexpression of decorin (DCN), one of the small leucine-rich proteoglycans, on the expression of extracellular matrix molecules in glomerular mesangial and tubular cells.Methods Recombinant adenovirus vector containing DCN gene (Ad/DCN) was constructed, and recombinant adenovirus containing LacZ gene (Ad/LacZ) was used as control vector.Rat renal glomerular mesangial cells of the line RMC and tubular cells of the line HK-2 were cultured and divided into following groups:high glucose + Ad/DCN transfection (experimental), high glucose + Ad/LacZ transfection (vector control), high glucose + neutralizing antibody against transforming growth factor (TGF) -β1(positive control) ,high glucose non-transfection (PBS control), and low glucose culture (normal control) groups.Western blotting was used to detect the protein expression of decorin, TGF-β1,collagen type Ⅳ, MMP-2, and MMP-9.Results The DCN protein expression was low only in the low glucose group, and was up-regulated in other groups, especially in the Ad/DCN group, so as the expression of TGF-β1 and collagen type Ⅳ, while the ratio of TGF-β1 to decorin is increased in both RMC and HK-2 cells.The expression levels of MMP-2 and MMP-9 decreased in the high-glucose-cuhured RMC cells and increased in the high-glucose-cultured HK-2 cells, however, adenovirus-mediated transfection of decorin gene reversed all of these changes,and had almost the same effects on reducing the protein expression of TGF-β1 collagen type Ⅳ, MMP-2, and MMP-9 as anti-TGF-β1 antibody.Conclusion The agents increasing the deeorin expression in mesangial and tubular cells may help prevent the development and progression of diabetic nephropathy.Overexpression of decorin may be a useful tool for developing new therapeutic application for the treatment of diabetic nephropathy.