CAJ | 학술논문

目的观察IgA肾病(IgAN)患者足细胞损伤的各种表现,探讨其与蛋白尿的关系.方法收集35例伴有明显蛋白尿[尿蛋白量(24 h)>1.0 gl的IgAN患者肾活检组织作研究;以8例肾错构瘤患者术后切除肾和肾癌患者术后远离癌旁肾组织为正常对照.免疫组化方法观察肾组织细胞周期调节蛋白(p21、p27)、足细胞结构蛋白(nestin)、足细胞数目(WT1).用显微切割方法取出肾小球,通过实时定量PCR方法检测整合素(integrin)β1、nephrin和α辅肌动蛋白4(α-actinin 4)水平.电镜观察足细胞超微结构的改变.根据足细胞数目密度(Nv,n×106/μm3)将35例IgAN患者分为足细胞数目减少组(Nv<52.49x106/μm3,n=15)和足细胞数目正常组(Nv≥52.49×106/μm3,rt=20).随访蛋白尿的转归情况,共18个月.结果 (1)与正常对照组比较,IgAN患者肾小球内个别足细胞重新表达p21,而足细胞p27的表达明显降低(0.71±0.12比0.91±0.07,P<0.05).(2)IgAN患者足细胞nestin蛋白表达比正常对照显著降低(13.40%±0.04%比17.60%±0.04%,P<0.05);肾小球内integrin-β1mRNA表达显著升高(12.54±5.20比1.02±0.30,P<0.05),而nephrin及α-actinin4 mRNA无明显改变.(3)电镜下观察到明显的足突融合和足细胞从基底膜脱落.(4)IgAN患者足细胞数目密度比正常对照组显著减少(161.27±225.92比323.22±138.12,P<0.05),且与Lee氏分级相关.(5)足细胞数目密度、integrin-β1 mRNA与肾穿刺当时的尿蛋白量(24 h)呈负相关r=-0.4483、-0.840,均P<0.05).足细胞数目减少组较足细胞数目正常组的蛋白尿下降程度明显减少(P<0.05).结论伴蛋白尿的IgAN中存在足细胞的损伤,表现为足细胞周期调节蛋白、结构蛋白的改变,足突的融合及足细胞数目的减少,而足细胞损伤及足细胞数目减少会影响蛋白尿的发生和发展.
목적 관찰IgA신병(IgAN)환자족세포손상적각충표현,탐토기여단백뇨적관계.방법 수집35례반유명현단백뇨[뇨단백량(24 h)>1.0 gl적IgAN환자신활검조직작연구;이8례신착구류환자술후절제신화신암환자술후원리암방신조직위정상대조.면역조화방법관찰신조직세포주기조절단백(p21、p27)、족세포결구단백(nestin)、족세포수목(WT1).용현미절할방법취출신소구,통과실시정량PCR방법검측정합소(integrin)β1、nephrin화α보기동단백4(α-actinin 4)수평.전경관찰족세포초미결구적개변.근거족세포수목밀도(Nv,n×106/μm3)장35례IgAN환자분위족세포수목감소조(Nv<52.49x106/μm3,n=15)화족세포수목정상조(Nv≥52.49×106/μm3,rt=20).수방단백뇨적전귀정황,공18개월.결과 (1)여정상대조조비교,IgAN환자신소구내개별족세포중신표체p21,이족세포p27적표체명현강저(0.71±0.12비0.91±0.07,P<0.05).(2)IgAN환자족세포nestin단백표체비정상대조현저강저(13.40%±0.04%비17.60%±0.04%,P<0.05);신소구내integrin-β1mRNA표체현저승고(12.54±5.20비1.02±0.30,P<0.05),이nephrin급α-actinin4 mRNA무명현개변.(3)전경하관찰도명현적족돌융합화족세포종기저막탈락.(4)IgAN환자족세포수목밀도비정상대조조현저감소(161.27±225.92비323.22±138.12,P<0.05),차여Lee씨분급상관.(5)족세포수목밀도、integrin-β1 mRNA여신천자당시적뇨단백량(24 h)정부상관r=-0.4483、-0.840,균P<0.05).족세포수목감소조교족세포수목정상조적단백뇨하강정도명현감소(P<0.05).결론 반단백뇨적IgAN중존재족세포적손상,표현위족세포주기조절단백、결구단백적개변,족돌적융합급족세포수목적 감소,이족세포손상급족세포수목감소회영향단백뇨적발생화발전.
Objective To investigate the injury of podocyte and its association with proteinuria in IgA nephropathy (IgAN). Method Thirty-five patients of IgA nephropathy with proteinuria more than 1.0 g/24 h were enrolled in the study, and eight cases of renal harmatomaeetomy or renal cancinomaectomy were as controls. Cell cycle regulatory proteins (p21, p27), podocyte-associated molecules (integrin-β1, nephrin, α-actinin 4, nestin), foot process width (FPW) and the amount of podocyte were examined by immunohistochemistry and real-time PCR, respectively. Patients were divided into two groups according to podocyte number per volume (Nv): podocytopenia group (n=15, Nv<52.49×106/μm3) and normal number group (n=20, Nv≥52.49× 106/μm3). Proteinuria was followed up for eighteen months. Results Compared with the controls, podocyte p21 was re-expressed, while the expression of p27 was decreased (0.71±0.12 vs 0.91±0.07, P<0.05) in IgAN. The nestin protein level was markedly decreased in IgAN (13.4%± 0.04% vs 17.6%±0.04%, P<0.05). The mRNA expression of integrin-β1 was significantly increased (12.54±5.20 vs 1.02±0.30, P<0.05), while the amount of nephrin, α-actinin4 remained unchanged. Effacement of foot processes and podocyte detachment from the glomerulax basement membrane were observed in some cases. Nv was significantly less than that of controls (161.27± 225.92 vs 323.22±138.12, P<0.05), which was associated with the Lee's grade of IgA nephropathy. The integrin-β1 mRNA expression and Nv were negatively correlated with baseline proteinuria by univariate analysis (r=-0.840, P=0.034; r =-0.4483, P=0.014, respectively). Proteinuria in podocytopenia group was decreased more slowly than that in normal number group. Conclusions Podocyte injury exsists in IgAN with proteinuria, which manifests alterations in cell cycle regulatory protein and some podocyte-associated molecules, as well as foot process effacement and loss of pedocyte. Podocyte injury may be involved in proteinuria by affecting the progression of proteinuria in IgAN.