维生素D受体在糖尿病肾病足细胞损伤及蛋白尿缓解中的作用

目的探讨维生素D受体(VDR)在糖尿病肾病(DKD)足细胞中的表达水平及在足细胞损伤及蛋白尿缓解中的作用。方法(1)本研究纳入了65例诊断患有2型糖尿病(伴或不伴蛋白尿)的患者,并纳入了25例年龄和性别相匹配的健康体检者为对照组。根据白蛋白/肌酐(ACR)的尿排泄比例对2型糖尿病患者进行分组,分别为无蛋白尿(ACR<30 mg/g,n=24)、微量白蛋白尿(ACR 30~300 mg/g,n=18)和临床蛋白尿(ACR>300 mg/g,n=23)。另选择25例经肾活检确诊的DKD患者作为DKD组。正常肾脏组织标本均取自泌尿外科同一时期肾脏肿瘤切除患者10例。将各组检测指标进行对比,同时采用实时定量PCR、ELISA法和免疫组化法检测VDR在各组患者的血液、尿液样本和肾脏组织中的表达情况,以及使用Pearson相关分析分析VDR与尿蛋白的相关性。(2)在2型糖尿病肾病小鼠模型中对上述结果进行验证,将遗传背景均为C57BLKs/J的雄性db/db小鼠及同窝出生的db/m小鼠,随机分为正常对照组(A组)、DKD对照组(B组)、DKD二甲基亚砜处理组(C组)、DKD帕立骨化醇(VDR激动剂)处理组(D组),C、D组连续腹腔注射处理8周,对照组不做任何处理。小鼠10周龄时开始连续干预8周,在小鼠22周龄(开始干预后12周)检测各组小鼠体重、血、尿生化指标对比;Western印迹法检测β⁃catenin、VDR的变化;免疫荧光观察足细胞标志蛋白podocin及足细胞损伤蛋白α⁃SMA的表达变化。结果(1)与正常健康对照组相比,无蛋白尿组、微量白蛋白尿组和临床蛋白尿组的糖尿病患者血浆中VDR的mRNA和蛋白水平均较低(均P<0.05);与无蛋白尿组的糖尿病患者相比,微量白蛋白尿组和临床蛋白尿组的糖尿病患者血浆中VDR的mRNA和蛋白水平均较低(均P<0.05)。(2)与正常健康对照组相比,无蛋白尿糖尿病组和DKD组患者血浆中VDR的mRNA和蛋白水平均较低(均P<0.05);与无蛋白尿糖尿病组患者相比,DKD组患者血浆中VDR的mRNA和蛋白水平亦较低(均P<0.05)。(3)免疫组化结果显示,DKD组肾组织中VDR的表达明显少于正常对照组。(4)DKD患者血浆中VDR mRNA相对水平与ACR呈负相关(r=-0.342,P<0.05)。(5)各组尿液上清液中VDR的水平与血浆中的水平呈相反趋势。(6)Western印迹结果显示,B组、C组肾小球足细胞β⁃catenin蛋白表达高于D组(均P<0.05),VDR蛋白的表达低于D组(均P<0.05);免疫荧光结果显示,B组、C组肾小球足细胞podocin的表达低于D组(均P<0.05),α⁃SMA的表达高于D组(均P<0.05)。结论VDR高表达缓解DKD足细胞损伤及蛋白尿。     

The angiotensin II receptor-neprilysin inhibitor LCZ696 attenuates the progression of proteinuria in type 2 diabetic rats

We examined the effects of the angiotensin receptor-neprilysin inhibitor LCZ696 on overt proteinuria and renal injury in type 2 diabetic Otsuka-Long- Evans-Tokushima-Fatty (OLETF) rats. Aged OLETF rats were also treated with either valsartan or valsartan plus hydralazine for comparison. LCZ696 caused greater attenuation of the progression of proteinuria than either valsartan alone or valsartan combined with hydralazine. Reduced glomerular injury and tubulointerstitial fibrosis were also observed in LCZ696-treated rats. Moreover, LCZ696 prevented increases in blood urea nitrogen (BUN) and creatinine levels. These data suggest that LCZ696 elicits a reno-protective effect against type 2 diabetes with overt proteinuria.     

伴免疫球蛋白G 沉积原发性膜性肾病病人疾病缓解影响因素及与肾小球免疫球蛋白G4 表达强度的关系研究

目的 探讨伴免疫球蛋白(Ig)G沉积原发性膜性肾病(PMN)病人疾病缓解影响因素及与肾小球IgG4表达强度的关系。方法 回顾性纳入山西省运城市中心医院2014年1月至2020年1月收治伴IgG沉积PMN病人共500例,根据有无IgG4表达和表达强度分组,分析临床病理及随访预后资料,采用单因素和多因素Cox回归模型评价伴IgG沉积PMN病人疾病缓解独立影响因素。结果 阳性组24 h尿蛋白量和M型磷脂酶A2受体(PLA2R)表达强度比例显著高于阴性组(P<0.05);弱阳性组、中阳性组及强阳性组血浆白蛋白、IgG1强度比例及IgA强度比例比较差异有统计学意义(P<0.05);阴性组、弱阳性组、中阳性组及强阳性组随访3个月( 30.0%比17.3%比15.9%比9.5%)和6个月(38.4%比30.6%比26.5%比13.0%)累积缓解率比较差异有统计学意义(P<0.05);Cox回归模型单因素和多因素分析结果显示,IgG4阳性高强度、男性、基线高24 h尿蛋白量均是伴IgG沉积PMN病人疾病未缓解独立危险因素［RR=1.33,95%CI:(1.05,1.61);RR=1.80,95%CI:(1.17,3.04);RR=1.51,95%CI:(1.09,2.80)。P<0.05］。结论 伴IgG沉积PMN病人疾病缓解效果与IgG4表达强度、性别及基线24 h尿蛋白量密切相关;而肾小球IgG4表达强度可作为PMN治疗反应性潜在评估指标加以应用。     

少量蛋白尿IgA肾病临床研究现状

少量蛋白尿IgA肾病(24 h尿蛋白<1 g)的患者既往认为长期预后良好,且肾活检比例低,普遍未予积极有效的治疗。近年来陆续有研究表明,少量蛋白尿IgA肾病患者长期预后并不乐观,因此需提高对少量蛋白尿IgA肾病临床、病理、治疗及预后的认识及理解。本文将对少量蛋白尿IgA肾病临床表现、肾脏病理、治疗及预后4个方面予以综述。     

Renal involvement in PMM2-CDG,a mini-review

Phosphomannomutase 2 deficiency (PMM2-CDG) is the most common N-linked glycosylation disorder. The majority of patients present with a multisystem phenotype, including central nervous system involvement, hepatopathy, gastrointestinal and cardiac symptoms, endocrine dysfunction and abnormal coagulation. Renal abnormalities including congenital malformations and altered renal function are part of the multisystem manifestations of congenital disorders of glycosylation.We reviewed the literature on 933 patients with molecularly and/or enzymatically confirmed PMM2 deficiency to evaluate the incidence of renal involvement in PMM2-CDG.Renal abnormalities were reported in 56 patients. Congenital abnormalities were present in 41 out of these 55. Cystic kidney and mild proteinuria were the most common findings. One of the most severe renal manifestations, congenital nephrotic syndrome, was detected in 6 children. Renal manifestations were not associated with the presence of specific PMM2 alleles.This review summarizes the reported renal abnormalities in PMM2-CDG and draws attention to the pathophysiological impact of abnormal glycosylation on kidney structure and function.     

Paradoxical fall in proteinuria during pregnancy in an LCAT-deficient patient—A case report

A 29-year-old lady was diagnosed with lecithin:cholesterol acyltransferase (LCAT) deficiency having presented with bilateral corneal clouding, severely reduced high density lipoproteins cholesterol, and proteinuria. She is a compound heterozygote with two LCAT gene mutations, one of which is novel, c.321C>A in exon 3. Surprisingly, the level of proteinuria significantly improved during pregnancy, despite stopping the angiotensin-converting enzyme inhibitor. However, LCAT concentration and activity remained identical during pregnancy and postpartum. Her pregnancy was complicated by rising triglyceride levels from the second trimester requiring treatment with omega-3 fatty acid and fenofibrate. In the last trimester, a further complication arose when she became hypertensive and proteinuria worsened. She was diagnosed with pre-eclampsia and had an emergency cesarean section at 39 weeks delivering a healthy baby. This case adds to the knowledge of the pathophysiology of LCAT deficiency during pregnancy and will be useful in future patient management.     

In glomerular cells of puromycin aminonucleoside nephrosis rats both phosphorylated and total STAT3 levels increased during proteinuria

Recent studies showed that JAK/STAT pathway plays role in glomerular damages. The fact that STAT3 could be activated also by oxidative stress make Puromycin Aminonucleoside (PAN) Nephrosis model very appropriate for examination of STAT3 expression changes in glomerular pathology. Along with a control group, three PAN groups sacrificed on different days were formed by the i.p. injection of PAN for 5 consecutive days. Throughout the experiment, 24-hour-urines were collected on specific days and proteinuria levels were monitored. At the end of the experiments, tissue specimens were stained immunohistochemically for both total and phosphorylated STAT3 and evaluated subjectively. They were also examined ultrastructurally in transmission electron microscope. The proteinuria levels did not increase significantly on 5th day but showed a dramatic increase on 10th and 15th days. On 20th and 25th days, urinary protein levels gradually decreased. Ultrastructural examinations showed glomerular damages such as significant decrease in slit pore number, a significant gradual increase in glomerular basement membrane thickness and podocyte hypertrophy on 5th and 15th days; besides significant increase in mesangial matrix. The first significant increases in phosphorylated and total STAT3 levels occurred in 5th day and 15th day groups respectively. These increases diminished in 25th day group. Regarding all the findings, it was deduced that STAT3 is one of the active factors in glomerular pathologies.