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Erythropoietin prevented the decreased expression of aquaporin1-3 in ureteral obstructive kidneys in juvenile rats. Pediatr Res 2022; 93:1258-1266. [PMID: 35986150 DOI: 10.1038/s41390-022-02224-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 06/17/2022] [Accepted: 07/18/2022] [Indexed: 11/09/2022]
Abstract
BACKGROUND Urinary tract obstruction is associated with impaired renal urinary concentration; even after the release of the obstruction, patients still suffer from polyuria. It has been reported that the decreased expression of aquaporins (AQPs) is associated with postobstructive polyuria, and erythropoietin (EPO) can promote the recovery of decreased AQP2 expression induced by bilateral ureteral obstruction. However, whether EPO can promote the recovery of the expression of AQP1-3 after the release of unilateral ureteral obstruction (UUO) has not yet been reported. AIMS To investigate the effects of EPO treatment on the expression of renal AQP1-3 after the release of UUO. METHODS UUO was established in rats by 24-h temporary unilateral obstruction of renal ureters. Three days following EPO treatment, the kidneys were removed to determine the expression levels of AQP1-3, NLRP3, caspase-1, and IL-1β via semiquantitative immunoblotting and immunohistochemistry. RESULTS EPO inhibited the expression of NLRP3, caspase-1, and IL-1β; reduced plasma creatinine and urea; and promoted the recovery of AQP1-3 expression in UUO rats. CONCLUSIONS EPO treatment prevented the decreased expression of renal AQPs and the development of impaired urinary concentration capacity after the release of UUO, which may partially occur by way of anti-inflammasome effects. IMPACT EPO treatment could prevent the decreased expression of renal water transporter proteins AQP1-3 and the development of impaired renal functions, which may be associated with its anti-inflammasome effects. EPO regulated the expression of renal water transporter proteins AQP1-3, which could provide the potential for the treatment of postobstructive polyuresis. EPO treatment could be one of the effective methods by participating in multiple dimensions for patients with obstructive nephropathy.
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Pérez-Etchepare Figueroa EL, Moraleda Mesa T, Hernández Rodríguez RA, Rosell Echevarría MJ, Tejera Carreño P, Luis Yanes MI, Monge Zamorano M, García Nieto VM. The use of urinary osmolality to evaluate postoperative renal function in children with ureteropelvic junction obstruction. J Pediatr Urol 2021; 17:513.e1-513.e7. [PMID: 34244058 DOI: 10.1016/j.jpurol.2021.05.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 04/12/2021] [Accepted: 05/25/2021] [Indexed: 11/25/2022]
Abstract
INTRODUCTION Split renal function measured in a diuretic renogram is the most popular tool in initial assessment and follow-up of patients with ureteropelvic junction obstruction (UPJO). This study aims to evaluate the use of maximum urinary osmolality after desmopressin administration (DDAVP) to detect renal dysfunction. PATIENTS AND METHODS 56 children (33 males, 23 females) diagnosed with UPJO underwent quantification of the maximum urinary osmolality (UOsm) at diagnosis. 41 of these children (28 males, 13 females) underwent surgery for UPJO and quantification of the UOsm before and after the surgical intervention (six to 18 months postoperatively) and were included in this longitudinal study. RESULTS AND DISCUSSION At diagnosis, UOsm measured after desmopressin administration was abnormal in 64% of patients. After surgical intervention, this rate decreased to 53%. At initial assessment, high creatinine levels were found in 32% of infants younger than one year of age. Albumin/Cr and NAG/Cr ratios were elevated in 12% and 7% of cases, respectively. After surgical intervention, an improvement in the NAG/creatinine ratio and creatinine levels was observed. Preoperative split renal function of the affected kidney was less than 45% in 39% of cases, normal in 44%, and greater than 55% in 17%; in these three subgroups, no differences in renal function markers were found. CONCLUSIONS The most sensitive parameter to detect alterations in renal function in children with UPJO is the UOsm and, therefore, the most useful in the follow-up after surgery. No correlation was found between other functional and morphological parameters obtained on renal ultrasound and renogram.
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Affiliation(s)
- Eduardo Luis Pérez-Etchepare Figueroa
- Pediatric Surgery Department, Nuestra Señora de Candelaria University Hospital, Hospital Universitario Nuestra Señora de Candelaria (Santa Cruz de Tenerife), Carretera del Rosario 145, Santa Cruz de Tenerife, CP 38010, Spain.
| | - Teresa Moraleda Mesa
- Pediatric Nephrology Department, Nuestra Señora de Candelaria University Hospital, Hospital Universitario Nuestra Señora de Candelaria (Santa Cruz de Tenerife), Carretera del Rosario 145, Santa Cruz de Tenerife, CP 38010, Spain.
| | - Raquel Angélica Hernández Rodríguez
- Pediatric Surgery Department, Nuestra Señora de Candelaria University Hospital, Hospital Universitario Nuestra Señora de Candelaria (Santa Cruz de Tenerife), Carretera del Rosario 145, Santa Cruz de Tenerife, CP 38010, Spain.
| | - María José Rosell Echevarría
- Pediatric Surgery Department, Nuestra Señora de Candelaria University Hospital, Hospital Universitario Nuestra Señora de Candelaria (Santa Cruz de Tenerife), Carretera del Rosario 145, Santa Cruz de Tenerife, CP 38010, Spain.
| | - Patricia Tejera Carreño
- Pediatric Nephrology Department, Nuestra Señora de Candelaria University Hospital, Hospital Universitario Nuestra Señora de Candelaria (Santa Cruz de Tenerife), Carretera del Rosario 145, Santa Cruz de Tenerife, CP 38010, Spain.
| | - María Isabel Luis Yanes
- Pediatric Nephrology Department, Nuestra Señora de Candelaria University Hospital, Hospital Universitario Nuestra Señora de Candelaria (Santa Cruz de Tenerife), Carretera del Rosario 145, Santa Cruz de Tenerife, CP 38010, Spain.
| | - Margarita Monge Zamorano
- Pediatric Nephrology Department, Nuestra Señora de Candelaria University Hospital, Hospital Universitario Nuestra Señora de Candelaria (Santa Cruz de Tenerife), Carretera del Rosario 145, Santa Cruz de Tenerife, CP 38010, Spain.
| | - Víctor Manuel García Nieto
- Pediatric Nephrology Department, Nuestra Señora de Candelaria University Hospital, Hospital Universitario Nuestra Señora de Candelaria (Santa Cruz de Tenerife), Carretera del Rosario 145, Santa Cruz de Tenerife, CP 38010, Spain.
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Feng J, Yan S, Chen Y, Han L, Wen L, Guo X, Wen Y, Li Y, He X, Han Z, Ren C, Jia Z, Guo Z, Zhai R, Wu J, Wen J. Aquaporin1-3 expression in normal and hydronephrotic kidneys in the human fetus. Pediatr Res 2019; 86:595-602. [PMID: 31261369 DOI: 10.1038/s41390-019-0485-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 06/06/2019] [Accepted: 06/16/2019] [Indexed: 11/09/2022]
Abstract
BACKGROUND Decreased expression of the renal aquaporin (AQP) protein family is associated with hydronephrosis in adult humans and animals. However, the expression of AQPs, especially subtypes AQP1-3, which play a core role in the urinary concentration function, in hydronephrotic human fetuses is not clear. The aim of this study is to investigate the expression of the AQP1-3 in normal and hydronephrotic human fetal kidneys. METHODS Twenty-one normal and six hydronephrotic kidney (HK) samples were harvested from abortive fetuses. Meanwhile, seven normal adult human kidney samples were collected as positive controls. Quantitative real-time PCR, western blotting, and immunohistochemistry were used to analyze the expression of AQP1-3. RESULTS Both the protein and messenger mRNA expression levels of AQP1-3 increased with gestational age in the normal fetuses, but the levels were significantly lower than those in the adult tissues and significantly higher than those in the hydronephrotic fetuses at the same gestational age. CONCLUSIONS The increased expression of AQP1-3 with gestational age in the fetal kidney may indicate maturation of the urinary concentrating ability. The lower expression of AQP1-3 in HKs may reflect a maturation obstacle with regard to urinary concentration in human hydronephrotic fetuses.
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Affiliation(s)
- Jinjin Feng
- Department of Pediatric Urodynamic Center and Henan Joint International Pediatric Urodynamic Laboratory, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China
| | - Shaohua Yan
- Department of Pediatric Urodynamic Center and Henan Joint International Pediatric Urodynamic Laboratory, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China
| | - Yan Chen
- Department of Pediatric Urodynamic Center and Henan Joint International Pediatric Urodynamic Laboratory, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China
| | - Liping Han
- Department of Gynaecology and Obstetrics, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China
| | - Lu Wen
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China
| | - Xi Guo
- Department of Pediatric Urodynamic Center and Henan Joint International Pediatric Urodynamic Laboratory, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China
| | - Yibo Wen
- Department of Pediatric Urodynamic Center and Henan Joint International Pediatric Urodynamic Laboratory, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China
| | - Yunlong Li
- Department of Pediatric Urodynamic Center and Henan Joint International Pediatric Urodynamic Laboratory, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China
| | - Xiangfei He
- Department of Pediatric Urodynamic Center and Henan Joint International Pediatric Urodynamic Laboratory, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China
| | - Zhongjiang Han
- Department of Pediatric Urodynamic Center and Henan Joint International Pediatric Urodynamic Laboratory, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China
| | - Chuanchuan Ren
- Department of Urology, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China
| | - Zhiming Jia
- Department of Urology, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China
| | - Zhan Guo
- Department of Urology, Children's Hospital of Henan Province, 450052, Zhengzhou, China
| | - Rongqun Zhai
- Department of Pediatric Urodynamic Center and Henan Joint International Pediatric Urodynamic Laboratory, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China
| | - Junwei Wu
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China
| | - Jianguo Wen
- Department of Pediatric Urodynamic Center and Henan Joint International Pediatric Urodynamic Laboratory, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China.
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Melatonin therapy protects against renal injury before and after release of bilateral ureteral obstruction in rats. Life Sci 2019; 229:104-115. [PMID: 31100324 DOI: 10.1016/j.lfs.2019.05.034] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 05/06/2019] [Accepted: 05/13/2019] [Indexed: 01/31/2023]
Abstract
AIM Blockage of the urinary tract is often connected with renal function impediment, including reductions in glomerular filtration rate (GFR) and the power to control sodium as well as water elimination through urination. Melatonin, known to be the primary product of the pineal gland, prevents renal damage caused by ischemic reperfusion. However, the effects of melatonin on urinary obstruction, as well as release of obstruction induced kidney injury are still largely unknown. The aim of present study was to investigate the effect of melatonin on mediating protection against renal injury triggered from either bilateral ureteral obstruction (BUO) or BUO release (BUO-R). MAIN METHODS Adult male Sprague-Dawley rats (n = 60) were clustered into six treatment groups: sham treated-1; BUO-non-treated (24 h BUO only); BUO + melatonin; sham treated-2; BUO-48hR (24 h of BUO and then release for 2 days); and BUO-48hR + melatonin. Kidney tissues, blood and urine samples were obtained for further assessment. KEY FINDINGS It was found that melatonin treatment remarkably promoted the recovery of the handling capacity of urinary excretion of water as well as sodium in BUO and BUO-48hR models. Melatonin treatment partially inhibited inflammatory cytokine expression and the downregulation of aquaporin (AQPs, AQP-1, -2 and -3) expression in these two models. Moreover, the cytoarchitecture of BUO rats exposed to melatonin was well preserved. SIGNIFICANCE Melatonin treatment potently prevents BUO or BUO-R induced renal injury, which may be partially attributed to restoring the expression of AQPs and inhibition of inflammatory response, as well as preserving renal ultrastructural integrity.
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Feng J, Chen Y, Yan S, Wen L, Guo X, Wen Y, Wen JG. The relationship between Aquaporin-2 protein levels in amniotic fluid and the fetal kidney in humans. Biochem Biophys Res Commun 2018; 506:585-589. [PMID: 30366672 DOI: 10.1016/j.bbrc.2018.10.097] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 10/16/2018] [Indexed: 02/04/2023]
Abstract
OBJECTIVES Aquaporin-2 (AQP2) is an important water channel protein that is expressed in the renal collecting duct and plays a key role in urine concentration and body water homeostasis. It has been demonstrated that the urinary excretion of AQP2 correlates strongly with its expression in the kidney in adult humans and rats. However, there have been no studies on the urinary excretion of AQP2 in human fetuses during development. Fetal urine is the main source of the amniotic fluid; we speculate that the level of AQP2 in the amniotic fluid could reflect the expression level of the AQP2 protein in the fetal kidney. The purpose of the present study was to explore the relationship between AQP2 in the amniotic fluid and that in the fetal kidney. METHODS In the present study, the concentration of the AQP2 protein in human amniotic fluid was measured by Enzyme-linked immunosorbent assay (ELISA) and its expression level in human fetal kidneys were examined by wastern blot and immunohistochemistry. RESULTS Both the expression level of AQP2 in the fetal kidney (F = 195.9, P < 0.001) and the concentration of AQP2 in the amniotic fluid increased with gestational age (F = 1098, P < 0.001). Moreover, the concentration of AQP2 in the amniotic fluid was positively correlated with its expression level in the fetal kidney (r = 0.872, P < 0.0001). CONCLUSIONS Our research indicates that AQP2 levels in the amniotic fluid may be used as a marker for AQP2 expression in the fetal kidney.
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Affiliation(s)
- Jinjin Feng
- Department of Pediatric Urodynamic Center& Henan Joint International Pediatric Urodynamic Laboratory, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Yan Chen
- Department of Pediatric Urodynamic Center& Henan Joint International Pediatric Urodynamic Laboratory, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Shaohua Yan
- Department of Pediatric Urodynamic Center& Henan Joint International Pediatric Urodynamic Laboratory, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Lu Wen
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Xi Guo
- Department of Pediatric Urodynamic Center& Henan Joint International Pediatric Urodynamic Laboratory, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Yibo Wen
- Department of Pediatric Urodynamic Center& Henan Joint International Pediatric Urodynamic Laboratory, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Jian Guo Wen
- Department of Pediatric Urodynamic Center& Henan Joint International Pediatric Urodynamic Laboratory, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China.
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The renal protect function of erythropoietin after release of bilateral ureteral obstruction in a rat model. Clin Sci (Lond) 2018; 132:2071-2085. [PMID: 29959186 DOI: 10.1042/cs20180178] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Revised: 06/20/2018] [Accepted: 06/29/2018] [Indexed: 11/17/2022]
Abstract
Congenital urinary tract obstruction is one of the most frequent malformations in fetuses or neonates, which usually causes profound impairment of renal function including reductions in both glomerular filtration rate (GFR) and tubular handling of water and solutes. Although obstruction can be released by surgical operation, the child will suffer from diuresis for sometime. It has been reported that erythropoietin (EPO) could prevent the down-regulation of aquaporin-2 (AQP2) and urinary-concentrating defects induced by renal ischemia/reperfusion (I/R) injury. However, whether EPO could promote the recovery of renal function and AQP2 expression after releasing of ureteral obstruction has not been reported yet. The purposes of the present study were to investigate the effects of EPO on renal function and AQP2 expression after release of bilateral ureteral obstruction (BUO-R) in rats. The results showed that EPO could promote interleukin (IL) 10 (IL-10) expression; inhibit tumor necrosis factor-α (TNF-α), IL-6, and inducible nitric oxide synthase (iNOS) expressions; reduce the fractional excretion of sodium (FENa) and plasma creatinine (CREA) and urea; and promote the recovery of water and salt handling and AQP2 expression in BUO-R rats, especially in the high dose of EPO-treated group rats. In conclusion, EPO could promote the recovery of renal function and AQP2 expression in BUO-R rats, which may partially associate with its anti-inflammation effect.
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7
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AQP4 and HIVAN. Exp Mol Pathol 2018; 105:71-75. [PMID: 29778884 DOI: 10.1016/j.yexmp.2018.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 05/13/2018] [Indexed: 11/21/2022]
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Abstract
Bartter syndrome (BS) type 1 (OMIM #601678) is a hereditary salt-losing renal tubular disorder characterized by hypokalemic metabolic alkalosis, hypercalciuria, nephrocalcinosis, polyuria, recurrent vomiting, and growth retardation. It is caused by loss-of-function mutations of the SLC12A1 gene, encoding the furosemide-sensitive Na-K-Cl cotransporter. Recently, a phenotypic variability has been observed in patients with genetically determined BS, including absence of nephrocalcinosis, hypokalemia, and/or metabolic alkalosis in the first year of life as well as persistent metabolic acidosis mimicking distal renal tubular acidosis. We report the case of a child with a genetically determined diagnosis of Bartter syndrome type 1 who presented with a phenotype of nephrogenic diabetes insipidus, with severe hypernatremia and urinary concentrating defect. In these atypical cases, molecular analysis is mandatory to define the diagnosis, in order to establish the correct clinical and therapeutic management.
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Jackson L, Woodward M, Coward RJ. The molecular biology of pelvi-ureteric junction obstruction. Pediatr Nephrol 2018; 33:553-571. [PMID: 28286898 PMCID: PMC5859056 DOI: 10.1007/s00467-017-3629-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 02/16/2017] [Accepted: 02/17/2017] [Indexed: 12/17/2022]
Abstract
Over recent years routine ultrasound scanning has identified increasing numbers of neonates as having hydronephrosis and pelvi-ureteric junction obstruction (PUJO). This patient group presents a diagnostic and management challenge for paediatric nephrologists and urologists. In this review we consider the known molecular mechanisms underpinning PUJO and review the potential of utilising this information to develop novel therapeutics and diagnostic biomarkers to improve the care of children with this disorder.
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Affiliation(s)
- Laura Jackson
- Bristol Renal Group, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol, BS1 3NY, UK. .,Bristol Royal Hospital for Children, Bristol, UK.
| | - Mark Woodward
- 0000 0004 0399 4960grid.415172.4Bristol Royal Hospital for Children, Bristol, UK
| | - Richard J. Coward
- 0000 0004 1936 7603grid.5337.2Bristol Renal Group, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol, BS1 3NY UK ,0000 0004 0399 4960grid.415172.4Bristol Royal Hospital for Children, Bristol, UK
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Abstract
Aquaporins (AQPs) are a 13 member family (AQP0-12) of proteins that act as channels, through which water and, for some family members, glycerol, urea and other small solutes can be transported. Aquaporins are highly abundant in kidney epithelial cells where they play a critical role with respect to water balance. In this review we summarize the current knowledge with respect to the localization and function of AQPs within the kidney tubule, and their role in mammalian water homeostasis and the water balance disorders. Overviews of practical aspects with regard to differential diagnosis for some of these disorders, alongside treatment strategies are also discussed.
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Affiliation(s)
- Hanne B Moeller
- Department of Biomedicine and Center for Interactions of Proteins in Epithelial Transport, Aarhus University, Denmark
| | - Cecilia H Fuglsang
- Department of Biomedicine and Center for Interactions of Proteins in Epithelial Transport, Aarhus University, Denmark
| | - Robert A Fenton
- Department of Biomedicine and Center for Interactions of Proteins in Epithelial Transport, Aarhus University, Denmark.
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Li ZZ, Xing L, Zhao ZZ, Li JS, Xue R, Chandra A, Nørregaard R, Wen JG. Decrease of renal aquaporins 1-4 is associated with renal function impairment in pediatric congenital hydronephrosis. World J Pediatr 2012; 8:335-41. [PMID: 23151861 DOI: 10.1007/s12519-012-0378-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2011] [Accepted: 04/23/2012] [Indexed: 11/29/2022]
Abstract
BACKGROUND Renal aquaporins (AQP1-4) concentration is downregulated and is in proportion to the degree of hydronephrosis graded by ultrasound in pediatric congenital hydronephrosis (CH). However, the relationship between the expression of AQP1-4 with the changes of renal function impairment (RFI) evaluated by (99m)Tc-DTPA renal dynamic imaging is still unclear. This study aimed to investigate the relationship between AQP1-4 expression and degree of RFI in children with CH. METHODS The expression of AQP1-4 was evaluated in 45 children with unilateral ureteropelvic junction obstruction (28 boys and 17 girls, average age: 28±10 months) and 15 children undergoing nephrectomy for nephroblastoma (8 boys and 7 girls, average age: 26±8 months) by immunoblotting and immunohistochemistry. Renal function was graded into mild and severe RFI by (99m)Tc-DTPA renal dynamic imaging. RESULTS One-way analysis of variance with Bonferonni's correction showed a significantly reduced protein expression of AQP1-4 in the severe RFI group compared with those in both mild RFI group and controls (AQP1: 0.52±0.09 vs. 0.91±0.06 vs. 1.23±0.033; AQP2: 0.68±0.12 vs. 1.09±0.06 vs. 1.52±0.08; AQP3: 0.59±0.16 vs. 0.94±0.08 vs. 1.31±0.07; AQP4: 0.64±0.06 vs. 1.14±0.07 vs. 1.61±0.07; P<0.001, respectively). In kidneys with severe RFI, there was a reduction in the protein concentration of all four AQP isoforms which was more pronounced compared with those seen in kidneys with mild RFI and in the controls. CONCLUSION AQP1-4 expression is reduced in proportion with the impairment degree of renal function graded by (99m)Tc-DTPA renal dynamic imaging in human CH.
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Affiliation(s)
- Zhen-Zhen Li
- The Institute of Clinical Medicine, First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
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Holmes RP. The role of renal water channels in health and disease. Mol Aspects Med 2012; 33:547-52. [PMID: 22252122 PMCID: PMC6900978 DOI: 10.1016/j.mam.2012.01.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Accepted: 01/04/2012] [Indexed: 12/21/2022]
Abstract
Seven members of the aquaporin (AQP) family are expressed in different regions of the kidney. AQP1-4 are localized in plasma membranes of renal epithelial cells and are intimately involved in water reabsorption by the kidney. AQP7 is also localized in the plasma membrane and may facilitate glycerol transport. AQP6 and AQP11 are localized within the cell, with AQP6 involved in anion transport and AQP11 water transport. Mutations in AQP2 can result in diabetes insipidus, whereas mutations in other AQPs have not yet been shown to be disease-associated. Genetic polymorphisms may contribute to the susceptibility to defects in urine concentrating mechanisms associated with some diseases. Most of the AQPs are subject to transcriptional regulation and post-translational modifications by a range of biological modifiers. As a result a number of chronic kidney and systemic diseases produce changes in the abundance of AQPs. The more recent developments in this field are reviewed.
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Affiliation(s)
- Ross P Holmes
- Department of Urology, Wake Forest University School of Medicine, Winston-Salem, Medical Center Blvd., NC 27157, USA.
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13
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Li ZZ, Zhao ZZ, Wen JG, Xing L, Zhang H, Zhang Y. Early alteration of urinary exosomal aquaporin 1 and transforming growth factor β1 after release of unilateral pelviureteral junction obstruction. J Pediatr Surg 2012; 47:1581-6. [PMID: 22901921 DOI: 10.1016/j.jpedsurg.2011.12.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 12/28/2011] [Accepted: 12/28/2011] [Indexed: 01/03/2023]
Abstract
BACKGROUND/PURPOSE Down-regulation of aquaporin 1 (AQP1) and up-regulation of transforming growth factor β(1) (TGF-β(1)) in the renal parenchyma have been demonstrated in children who underwent pyeloplasty for pelviureteral junction obstruction. However, no information about urinary exosomal AQP1 and TGF-β(1) during postobstructive polyuria in children with congenital unilateral hydronephrosis is available. The aim of the present study is to evaluate the urine concentration of exosomal AQP1 and TGF-β(1) on the first and the second day after surgery in children who underwent pyeloplasty. METHODS Twenty-two patients (age, 36.2 ± 17.1 months) with unilateral pelviureteral junction obstruction were examined in the study. For the first 2 days after the operation, the urine was collected separately from pyelostomy draining only from the postobstructed kidney and from the bladder catheter draining mostly from the contralateral kidney, which was used as an internal control. Urinary output, urinary osmolality, sodium, β(2)-microglobulin (β(2)-MG), and creatinine, as well as urinary exosomal AQP1 and TGF-β(1) excretion, were tested in each sample. RESULTS After pyeloplasty, a significantly decreased urinary excretion of exosomal AQP1 (≈ 64%) was found in the postobstructed kidney. The patients developed polyuria (807 ± 216 mL/24 h vs 484 ± 144 mL/24 h at day 1, 1021 ± 348 mL/24 h vs 603 ± 228 mL/24 h at day 2; P < .01) and reduced urine osmolality (115 ± 44 mOsm/kg vs 282 ± 61 mOsm/kg at day 1, 139 ± 39 vs 303 ± 46 mOsm/kg at day 2; P < .01) that persisted for 48 hours. In parallel, urinary TGF-β(1) and β(2)-MG (normalized for creatinine) from the postobstructed kidney were significantly higher compared with the contralateral kidney. The urine output and urinary sodium concentration from the postobstructed kidney elevated significantly on the second day after the release of obstruction compared with those on the first day. The contralateral kidney also showed same trends. CONCLUSIONS The down-regulation of urinary exosomal AQP1 in the postobstructed kidney may account for the polyuria, hypotonic urine, and elevated urinary β(2)-MG. The urinary TGF-β(1) level locally increased in the postobstructed kidney may be involved in renal AQP1 down-regulation.
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Affiliation(s)
- Zhen Zhen Li
- The Institute of Clinical Medicine, The First Affiliated Hospital of Zhengzhou University, Henan 450052, China.
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Ampawong S, Klincomhum A, Likitsuntonwong W, Singha O, Ketjareon T, Panavechkijkul Y, Zaw KM, Kengkoom K. Expression of Aquaporin-1, -2 and -4 in Mice with a Spontaneous Mutation Leading to Hydronephrosis. J Comp Pathol 2012; 146:332-7. [DOI: 10.1016/j.jcpa.2011.08.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Revised: 07/21/2011] [Accepted: 08/11/2011] [Indexed: 11/16/2022]
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