Case Control Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Nov 26, 2019; 7(22): 3698-3710
Published online Nov 26, 2019. doi: 10.12998/wjcc.v7.i22.3698
Human podocyte injury in the early course of hypertensive renal injury
Da Sun, Jiao-Jiao Wang, Wei Wang, Juan Wang, Li-Ning Wang, Li Yao, Ying-Hui Sun, Zi-Long Li
Da Sun, Jiao-Jiao Wang, Wei Wang, Juan Wang, Li-Ning Wang, Li Yao, Zi-Long Li, Department of Nephrology, The First Hospital of China Medical University, Shenyang 110001, Liaoning Province, China
Ying-Hui Sun, Department of Experimental Medicine, General Hospital of Northern Theater Command, Shenyang 110016, Liaoning Province, China
Author contributions: Sun YH and Li ZL conceived the study; Sun D, Wang JJ, Wang W and Wang J collected the clinical data and biological specimens and performed the research; Wang LN and Yao L analyzed the data; Sun D and Li ZL drafted the manuscript; all authors approved the final version of the article.
Supported by the Natural Science Foundation of Liaoning Provincial Department of Science and Technology, No. 2017225020.
Institutional review board statement: The study was approved by Clinical Institutional Review Board for Human Research (Ethics Committee) of China Medical University.
Informed consent statement: Written informed consent was obtained from all participants prior to enrollment in the study.
Data sharing statement: Technical appendix, statistical code, and dataset available from the corresponding author at yinghui_sun@163.com. Participants gave informed consent for data sharing.
STROBE statement: The guidelines of the STROBE Statement have been adopted.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Ying-Hui Sun, MD, Associate Chief Physician, Department of Experimental Medicine, General Hospital of Northern Theater Command, No. 83 Wenhua Road, Shenhe District, Shenyang 110016, Liaoning Province, China. yinghui_sun@163.com
Telephone: +86-24-28851712
Received: September 8, 2019
Peer-review started: September 8, 2019
First decision: October 24, 2019
Revised: November 3, 2019
Accepted: November 15, 2019
Article in press: November 15, 2019
Published online: November 26, 2019
Abstract
BACKGROUND

Hypertension is prevalent in the general population and is regarded as the second leading cause of renal damage and dysfunction, outnumbered only by diabetes. However, the mechanisms remain unclear.

AIM

To investigate podocyte injury induced by hypertension in the early course without massive proteinuria or renal dysfunction.

METHODS

The hypertension group comprised 18 patients with hypertension accompanied by microalbuminuria, diagnosed with hypertensive renal injury according to biopsy results. For a comparison of pathological changes in renal tissue, control group 1 comprised 10 healthy volunteers, and control group 2 comprised 16 patients who underwent surgery for renal trauma.

RESULTS

The hypertension group had significantly higher blood pressure (P = 0.000) and microalbuminuria (P = 0.000) compared with control group 1. In the hypertension group, urinary podocytes were detected following positive staining of podocyte-specific nephrin and/or CD2-associated protein (CD2AP) in urine sediment. Podocyte foot process fusion and a significant decrease in nephrin and/or CD2AP expression in glomeruli were observed in the hypertension group compared with control group 2. This indicated that hypertension caused podocyte injury and detachment from the glomerular basement membrane, which was consistent with urinary detection of podocytes.

CONCLUSION

Our results suggest that podocyturia appears early in the course of hypertensive renal injury, and may be a sensitive marker for early prediction of hypertensive renal injury.

Keywords: Podocyte, Hypertension, Hypertensive renal injury, Microalbuminuria, Nephrin, CD2-associated protein

Core tip: Podocytes probably play a crucial role in the pathogenesis of hypertensive renal injury, but human data are limited. In this study, we detected podocytes from urine sediments of patients with chronic hypertension and trace proteinuria, and obtained direct evidence that podocyte loss is not only associated with severe renal damage in chronic hypertension, but also occurs in the early course of hypertensive renal injury. We found that intrarenal expression of nephrin and CD2-associated protein was downregulated and consistent with podocyte shedding.