重组人促红细胞生成素预处理通过降低瞬时受体电位通道 6-激活 T 细胞核因子途径的激活减轻体外循环引起的肾肾小球损伤。

Recombinant human erythropoietin pretreatment alleviates renal glomerular injury induced by cardiopulmonary bypass by reducing transient receptor potential channel 6-nuclear factor of activated T-cells pathway activation.

机构信息

Department of Anesthesiology, Nanjing Jinling Hospital, Nanjing, China.

出版信息

J Thorac Cardiovasc Surg. 2013 Sep;146(3):681-7. doi: 10.1016/j.jtcvs.2013.02.076. Epub 2013 Mar 25.

DOI:10.1016/j.jtcvs.2013.02.076

PMID:23535151

Abstract

OBJECTIVE

Acute renal injury after cardiopulmonary bypass is common and associated with high mortality. We aimed to demonstrate the glomerular protective effects of recombinant human erythropoietin using an in vivo rat cardiopulmonary bypass model and to explore the possible mechanism.

METHODS

Dose-related renal protective effects of recombinant human erythropoietin were studied in phase I. Male Sprague Dawley rats were randomly divided into 5 groups: sham group, cardiopulmonary bypass group, and 3 recombinant human erythropoietin-treated cardiopulmonary bypass groups (bolus doses of 500, 3000, and 5000 U/kg 24 hours before surgery). Blood and urine samples were collected just before surgery and at 2, 4, 24, 48, and 72 hours after surgery. In phase II, rats were divided into 3 groups: sham group, cardiopulmonary bypass group, and 5000 U/kg recombinant human erythropoietin group. Kidneys were harvested at 4, 24, 48, and 72 hours after surgery. Ultra-organization of glomeruli was observed. Glomerular transient receptor potential channel 6 (TRPC6) expression was studied by immunofluorescence and Western blot. Nuclei nuclear factor of activated T-cells, cytoplasmic, calcineurin-dependent 1 (NFATc1) activity was analyzed by enzyme-linked immunosorbent assays and electrophoretic mobility shift assay.

RESULTS

Pretreatment of 5000 U/kg recombinant human erythropoietin decreased the urine protein (72 hours: 7.82 ± 1.13 g/L vs 11.28 ± 1.73 g/L), serum creatinine (72 hours: 35.0 ± 3.5 μmol/L vs 60.7 ± 7.6 μmol/L), and cystatin-C (2 hours: 336.5 ± 28.2 μg/L vs 452.6 ± 63.8 μg/L) compared with the control group (P < .01). Cardiopulmonary bypass induced morphologic abnormalities of podocyte foot processes and slit diaphragms, which was improved by recombinant human erythropoietin. Furthermore, recombinant human erythropoietin significantly relieved glomerular TRPC6 increase and NFATc1 activation induced by cardiopulmonary bypass.

CONCLUSIONS

Pretreatment of 5000 U/kg recombinant human erythropoietin elicited potent glomerular protection against cardiopulmonary bypass. This protection may be partly due to downregulation of glomerular TRPC6-NFATc1 pathway.

摘要

目的

体外循环后急性肾损伤很常见，且与高死亡率相关。本研究旨在通过建立活体大鼠体外循环模型，证明重组人促红细胞生成素的肾小球保护作用，并探讨其可能的机制。

方法

在 I 期研究中，我们研究了重组人促红细胞生成素的剂量相关性肾保护作用。雄性 Sprague Dawley 大鼠随机分为 5 组：假手术组、体外循环组和 3 组重组人促红细胞生成素处理的体外循环组（术前 24 小时分别给予 500、3000 和 5000 U/kg 的剂量）。分别在术前和术后 2、4、24、48 和 72 小时采集血样和尿样。在 II 期研究中，大鼠分为 3 组：假手术组、体外循环组和 5000 U/kg 重组人促红细胞生成素组。分别在术后 4、24、48 和 72 小时采集肾脏组织。观察肾小球超微结构。通过免疫荧光和 Western blot 检测肾小球瞬时受体电位通道 6（TRPC6）的表达。通过酶联免疫吸附试验和电泳迁移率变动分析检测核因子活化 T 细胞胞浆，钙调神经磷酸酶依赖性 1（NFATc1）的活性。

结果

5000 U/kg 重组人促红细胞生成素预处理降低了尿蛋白（72 小时：7.82±1.13 g/L 比 11.28±1.73 g/L）、血清肌酐（72 小时：35.0±3.5 μmol/L 比 60.7±7.6 μmol/L）和胱抑素 C（2 小时：336.5±28.2 μg/L 比 452.6±63.8 μg/L），与对照组相比差异均有统计学意义（P<.01）。体外循环引起足细胞足突和裂孔隔膜的形态异常，而重组人促红细胞生成素可改善这种异常。此外，重组人促红细胞生成素可显著减轻体外循环引起的肾小球 TRPC6 增加和 NFATc1 激活。