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Ge WD, Du TT, Wang CY, Sun LN, Wang YQ. Calcium signaling crosstalk between the endoplasmic reticulum and mitochondria, a new drug development strategies of kidney diseases. Biochem Pharmacol 2024; 225:116278. [PMID: 38740223 DOI: 10.1016/j.bcp.2024.116278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 04/25/2024] [Accepted: 05/10/2024] [Indexed: 05/16/2024]
Abstract
Calcium (Ca2+) acts as a second messenger and constitutes a complex and large information exchange system between the endoplasmic reticulum (ER) and mitochondria; this process is involved in various life activities, such as energy metabolism, cell proliferation and apoptosis. Increasing evidence has suggested that alterations in Ca2+ crosstalk between the ER and mitochondria, including alterations in ER and mitochondrial Ca2+ channels and related Ca2+ regulatory proteins, such as sarco/endoplasmic reticulum Ca2+-ATPase (SERCA), inositol 1,4,5-trisphosphate receptor (IP3R), and calnexin (CNX), are closely associated with the development of kidney disease. Therapies targeting intracellular Ca2+ signaling have emerged as an emerging field in the treatment of renal diseases. In this review, we focused on recent advances in Ca2+ signaling, ER and mitochondrial Ca2+ monitoring methods and Ca2+ homeostasis in the development of renal diseases and sought to identify new targets and insights for the treatment of renal diseases by targeting Ca2+ channels or related Ca2+ regulatory proteins.
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Affiliation(s)
- Wen-Di Ge
- Research Division of Clinical Pharmacology, the First Affiliated Hospital of Nanjing Medical University & Jiangsu Province Hospital, Nanjing, China; Department of Pharmacy, Nanjing Medical University, Nanjing, China
| | - Tian-Tian Du
- Research Division of Clinical Pharmacology, the First Affiliated Hospital of Nanjing Medical University & Jiangsu Province Hospital, Nanjing, China; Department of Pharmacy, Nanjing Medical University, Nanjing, China
| | - Cao-Yang Wang
- Research Division of Clinical Pharmacology, the First Affiliated Hospital of Nanjing Medical University & Jiangsu Province Hospital, Nanjing, China; Department of Pharmacy, Nanjing Medical University, Nanjing, China
| | - Lu-Ning Sun
- Research Division of Clinical Pharmacology, the First Affiliated Hospital of Nanjing Medical University & Jiangsu Province Hospital, Nanjing, China; Department of Pharmacy, Nanjing Medical University, Nanjing, China.
| | - Yong-Qing Wang
- Research Division of Clinical Pharmacology, the First Affiliated Hospital of Nanjing Medical University & Jiangsu Province Hospital, Nanjing, China; Department of Pharmacy, Nanjing Medical University, Nanjing, China.
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2
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Yu S, Gu X, Zheng Q, Liu Y, Suhas T, Du W, Xie L, Fang Z, Zhao Y, Yang M, Xu J, Wang Y, Lin MH, Pan X, Miner JH, Jin Y, Xie J. Tauroursodeoxycholic acid ameliorates renal injury induced by COL4A3 mutation. Kidney Int 2024:S0085-2538(24)00334-X. [PMID: 38782199 DOI: 10.1016/j.kint.2024.04.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Revised: 03/17/2024] [Accepted: 04/25/2024] [Indexed: 05/25/2024]
Abstract
COL4A3/A4/A5 mutations have been identified as critical causes of Alport syndrome and other genetic chronic kidney diseases. However, the underlying pathogenesis remains unclear, and specific treatments are lacking. Here, we constructed a transgenic Alport syndrome mouse model by generating a mutation (Col4a3 p.G799R) identified previously from one large Alport syndrome family into mice. We observed that the mutation caused a pathological decrease in intracellular and secreted collagen IV α3α4α5 heterotrimers. The mutant collagen IV α3 chains abnormally accumulated in the endoplasmic reticulum and exhibited defective secretion, leading to persistent endoplasmic reticulum stress in vivo and in vitro. RNA-seq analysis revealed that the MyD88/p38 MAPK pathway plays key roles in mediating subsequent inflammation and apoptosis signaling activation. Treatment with tauroursodeoxycholic acid, a chemical chaperone drug that functions as an endoplasmic reticulum stress inhibitor, effectively suppressed endoplasmic reticulum stress, promoted secretion of the α3 chains, and inhibited the activation of the MyD88/p38 MAPK pathway. Tauroursodeoxycholic acid treatment significantly improved kidney function in vivo. These results partly clarified the pathogenesis of kidney injuries associated with Alport syndrome, especially in glomeruli, and suggested that tauroursodeoxycholic acid might be useful for the early clinical treatment of Alport syndrome.
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Affiliation(s)
- Shuwen Yu
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Nephrology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiangchen Gu
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Nephrology, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Department of Nephrology, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Qimin Zheng
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Nephrology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yunzi Liu
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Nephrology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Teija Suhas
- Division of Nephrology, Department of Medicine and Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Wen Du
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Nephrology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Lin Xie
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Nephrology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhengying Fang
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Nephrology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yafei Zhao
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Nephrology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Mingxin Yang
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Nephrology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jing Xu
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Nephrology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yimei Wang
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Nephrology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Meei-Hua Lin
- Division of Nephrology, Department of Medicine and Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Xiaoxia Pan
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Nephrology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine and Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Yuanmeng Jin
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Nephrology, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Jingyuan Xie
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Nephrology, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
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Lujinschi ȘN, Sorohan BM, Obrișcă B, Vrabie A, Lupușoru G, Achim C, Andronesi AG, Covic A, Ismail G. Genotype-Phenotype Correlations in Alport Syndrome-A Single-Center Experience. Genes (Basel) 2024; 15:593. [PMID: 38790222 PMCID: PMC11121304 DOI: 10.3390/genes15050593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2024] [Revised: 05/02/2024] [Accepted: 05/03/2024] [Indexed: 05/26/2024] Open
Abstract
BACKGROUND Alport syndrome (AS) is a common and heterogeneous genetic kidney disease, that often leads to end-stage kidney disease (ESKD). METHODS This is a single-center, retrospective study that included 36 adults with type IV collagen (COL4) mutations. Our main scope was to describe how genetic features influence renal survival. RESULTS A total of 24 different mutations were identified, of which eight had not been previously described. Mutations affecting each of the type IV collagen α chains were equally prevalent (33.3%). Most of the patients had pathogenic variants (61.1%). Most patients had a family history of kidney disease (71%). The most prevalent clinical picture was nephritic syndrome (64%). One-third of the subjects had extrarenal manifestations, 41.6% of patients had ESKD at referral, and another 8.3% developed ESKD during follow-up. The median renal survival was 42 years (95% CI, 29.98-54.01). The COL4A4 group displayed better renal survival than the COL4A3 group (p = 0.027). Patients with missense variants had higher renal survival (p = 0.023). Hearing loss was associated with lower renal survival (p < 0.001). CONCLUSIONS Patients with COL4A4 variants and those with missense mutations had significantly better renal survival, whereas those with COL4A3 variants and those with hearing loss had worse prognoses.
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Affiliation(s)
- Ștefan Nicolaie Lujinschi
- Department of Nephrology, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (B.M.S.); (B.O.); (A.V.); (G.L.); (C.A.); (A.G.A.); (G.I.)
- Department of Nephrology, Fundeni Clinical Institute, 022328 Bucharest, Romania
| | - Bogdan Marian Sorohan
- Department of Nephrology, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (B.M.S.); (B.O.); (A.V.); (G.L.); (C.A.); (A.G.A.); (G.I.)
- Department of Nephrology, Fundeni Clinical Institute, 022328 Bucharest, Romania
| | - Bogdan Obrișcă
- Department of Nephrology, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (B.M.S.); (B.O.); (A.V.); (G.L.); (C.A.); (A.G.A.); (G.I.)
- Department of Nephrology, Fundeni Clinical Institute, 022328 Bucharest, Romania
| | - Alexandra Vrabie
- Department of Nephrology, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (B.M.S.); (B.O.); (A.V.); (G.L.); (C.A.); (A.G.A.); (G.I.)
- Department of Nephrology, Fundeni Clinical Institute, 022328 Bucharest, Romania
| | - Gabriela Lupușoru
- Department of Nephrology, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (B.M.S.); (B.O.); (A.V.); (G.L.); (C.A.); (A.G.A.); (G.I.)
- Department of Nephrology, Fundeni Clinical Institute, 022328 Bucharest, Romania
| | - Camelia Achim
- Department of Nephrology, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (B.M.S.); (B.O.); (A.V.); (G.L.); (C.A.); (A.G.A.); (G.I.)
- Department of Nephrology, Fundeni Clinical Institute, 022328 Bucharest, Romania
| | - Andreea Gabriella Andronesi
- Department of Nephrology, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (B.M.S.); (B.O.); (A.V.); (G.L.); (C.A.); (A.G.A.); (G.I.)
- Department of Nephrology, Fundeni Clinical Institute, 022328 Bucharest, Romania
| | - Andreea Covic
- Faculty of Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania;
- Nephrology Depatment, Dialysis and Renal Transplant Center, “Dr. C. I. Parhon” Clinical Hospital, 700503 Iasi, Romania
| | - Gener Ismail
- Department of Nephrology, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (B.M.S.); (B.O.); (A.V.); (G.L.); (C.A.); (A.G.A.); (G.I.)
- Department of Nephrology, Fundeni Clinical Institute, 022328 Bucharest, Romania
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Puapatanakul P, Miner JH. Alport syndrome and Alport kidney diseases - elucidating the disease spectrum. Curr Opin Nephrol Hypertens 2024; 33:283-290. [PMID: 38477333 PMCID: PMC10990029 DOI: 10.1097/mnh.0000000000000983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2024]
Abstract
PURPOSE OF REVIEW With the latest classification, variants in three collagen IV genes, COL4A3 , COL4A4 , and COL4A5 , represent the most prevalent genetic kidney disease in humans, exhibiting diverse, complex, and inconsistent clinical manifestations. This review breaks down the disease spectrum and genotype-phenotype correlations of kidney diseases linked to genetic variants in these genes and distinguishes "classic" Alport syndrome (AS) from the less severe nonsyndromic genetically related nephropathies that we suggest be called "Alport kidney diseases". RECENT FINDINGS Several research studies have focused on the genotype-phenotype correlation under the latest classification scheme of AS. The historic diagnoses of "benign familial hematuria" and "thin basement membrane nephropathy" linked to heterozygous variants in COL4A3 or COL4A4 are suggested to be obsolete, but instead classified as autosomal AS by recent expert consensus due to a significant risk of disease progression. SUMMARY The concept of Alport kidney disease extends beyond classic AS. Patients carrying pathogenic variants in any one of the COL4A3/A4/A5 genes can have variable phenotypes ranging from completely normal/clinically unrecognizable, hematuria without or with proteinuria, or progression to chronic kidney disease and kidney failure, depending on sex, genotype, and interplays of other genetic as well as environmental factors.
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Affiliation(s)
- Pongpratch Puapatanakul
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
- Division of Nephrology, Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Jeffrey H. Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
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Tong J, Zheng Q, Gu X, Weng Q, Yu S, Fang Z, Jafar Hussain HM, Xu J, Ren H, Chen N, Xie J. COL4A3 Mutation Induced Podocyte Apoptosis by Dysregulation of NADPH Oxidase 4 and MMP-2. Kidney Int Rep 2023; 8:1864-1874. [PMID: 37705901 PMCID: PMC10496016 DOI: 10.1016/j.ekir.2023.06.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 05/15/2023] [Accepted: 06/05/2023] [Indexed: 09/15/2023] Open
Abstract
Introduction Podocyte apoptosis is a common mechanism driving progression in Alport syndrome (AS). This study aimed to investigate the mechanism of podocyte apoptosis caused by COL4A3 mutations. Methods We recruited patients with autosomal dominant AS (ADAS). Patients with minimal change disease (MCD) were recruited as controls. Microarray analysis was carried out on isolated glomeruli from the patients and validated. Then, corresponding mutant human podocytes (p.C1616Y) and 129 mice (p.C1615Y, the murine homolog to the human p.C1616Y) were constructed. The highest differentially expressed genes (DEGs) from microarray analysis were validated in transgenic mice and podocytes before and after administration of MMP-2 inhibitor (SB-3CT) and NOX4 inhibitor (GKT137831). We further validated NOX4/MMP-2/apoptosis pathway by real-time polymerase chain reaction (PCR), immunohistochemistry, and western blot in renal tissues from the ADAS patients. Results Using microarray analysis, we observed that DEGs, including NOX4/H2O2, MMP-2, and podocyte apoptosis-related genes were significantly upregulated. These genes were validated by real-time PCR, histologic analysis, and western blot in corresponding mutant human podocyte (p.C1616Y) and/or mice models (p.C1615Y). Moreover, we found podocyte apoptosis was abrogated and MMP-2 expression was down-regulated both in vivo and in vitro by NOX4 inhibition, urinary albumin-to-creatinine ratio, 24-hour proteinuria; and renal pathologic lesion was attenuated by NOX4 inhibition in vivo. Furthermore, podocyte apoptosis was attenuated whereas NOX4 expression remained the same by inhibition of MMP-2 both in vivo and in vitro. Conclusion These results indicated that NOX4 might induce podocyte apoptosis through the regulation of MMP-2 in patients with COL4A3 mutations. Our findings provided new insights into the mechanism of ADAS.
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Affiliation(s)
- Jun Tong
- Department of Nephrology, Institute of Nephrology, Shanghai Ruijin Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Qimin Zheng
- Department of Nephrology, Institute of Nephrology, Shanghai Ruijin Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Xiangchen Gu
- Department of Nephrology, Institute of Nephrology, Shanghai Ruijin Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Qinjie Weng
- Department of Nephrology, Institute of Nephrology, Shanghai Ruijin Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Shuwen Yu
- Department of Nephrology, Institute of Nephrology, Shanghai Ruijin Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Zhengying Fang
- Department of Nephrology, Institute of Nephrology, Shanghai Ruijin Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Hafiz Muhammad Jafar Hussain
- Department of Nephrology, Institute of Nephrology, Shanghai Ruijin Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Jing Xu
- Department of Nephrology, Institute of Nephrology, Shanghai Ruijin Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Hong Ren
- Department of Nephrology, Institute of Nephrology, Shanghai Ruijin Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Nan Chen
- Department of Nephrology, Institute of Nephrology, Shanghai Ruijin Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Jingyuan Xie
- Department of Nephrology, Institute of Nephrology, Shanghai Ruijin Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
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Alge JL, Bekheirnia N, Willcockson AR, Qin X, Scherer SE, Braun MC, Bekheirnia MR. Variants in genes coding for collagen type IV α-chains are frequent causes of persistent, isolated hematuria during childhood. Pediatr Nephrol 2023; 38:687-695. [PMID: 35759000 DOI: 10.1007/s00467-022-05627-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 05/04/2022] [Accepted: 05/06/2022] [Indexed: 01/19/2023]
Abstract
BACKGROUND Children with persistent, isolated microscopic hematuria typically undergo a limited diagnostic workup and are monitored for signs of kidney disease in long-term longitudinal follow-up, which can delay diagnosis and allow disease progression in some cases. METHODS To determine the clinical utility of genetic screening in this population, we performed targeted genetic testing using a custom, 32-gene next-generation sequencing panel for progressive kidney disease on children referred to the Texas Children's Hospital Pediatric Nephrology clinic for persistent, microscopic hematuria (n = 30; cohort 1). Patients with microscopic hematuria identified by urinalysis on at least two separate occasions were eligible for enrollment, but those with other evidence of kidney disease were excluded. Results were analyzed for sequence variants using the American College of Medical Genetics and Genomics (ACMG) guideline for data interpretation and were validated using a secondary analysis of a dataset of children with hematuria and normal kidney function who had undergone genetic testing as part of an industry-sponsored program (cohort 2; n = 67). RESULTS In cohort 1 33% of subjects (10/30) had pathogenic or likely pathogenic (P/LP) variants in the type IV collagen genes (COL4A3/A4/A5), and 10% (3/30) had variants of uncertain significance in these genes. The high diagnostic rate in type IV collagen genes was confirmed in cohort 2, where 27% (18/67) of subjects had P/LP variants in COL4A3/A4/A5 genes. CONCLUSIONS Children with persistent, isolated microscopic hematuria have a high likelihood of having pathogenic variants in type IV collagen genes and genetic screening should be considered. A higher resolution version of the Graphical abstract is available as Supplementary information.
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Affiliation(s)
- Joseph L Alge
- Department of Pediatrics, Division of Pediatric Nephrology, Baylor College Medicine, Houston, TX, 77030, USA
| | - Nasim Bekheirnia
- Department of Pediatrics, Division of Pediatric Nephrology, Baylor College Medicine, Houston, TX, 77030, USA
| | | | - Xiang Qin
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Steven E Scherer
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, 77030, USA.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Michael C Braun
- Department of Pediatrics, Division of Pediatric Nephrology, Baylor College Medicine, Houston, TX, 77030, USA
| | - Mir Reza Bekheirnia
- Department of Pediatrics, Division of Pediatric Nephrology, Baylor College Medicine, Houston, TX, 77030, USA. .,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA.
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Horaček M, Martić TN, Šenjug P, Perica MŠ, Oroz M, Kuzmac S, Klarić D, Glavina Durdov M, Saraga M, Milošević D, Batinić D, Ćorić M, Paić F, Ljubanović DG. Clinical and histopathological characteristics of COL4A3 c.2881+1G>A variant causing Alport spectrum disorders in Croatian population. BIOMOLECULES AND BIOMEDICINE 2023; 23:89-100. [PMID: 35880347 PMCID: PMC9901899 DOI: 10.17305/bjbms.2022.7567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 06/28/2022] [Indexed: 02/08/2023]
Abstract
Alport syndrome (AS) and thin basement membrane nephropathy (TBMN) are part of the spectrum of kidney disorders caused by pathogenic variants in α3, α4, or α5 chains of the collagen type IV, the major structural component of the glomerular basement membrane (GBM). Using targeted next-generation sequencing (NGS), 34 AS/TBMN patients (58.8% male) from 12 unrelated families were found positive for heterozygous c.2881+1G>A variant of the COL4A3gene, that is considered disease-causing. All patients were from the continental or island part of Croatia. Clinical, laboratory, and histopathological data collected from the medical records were analyzed and compared to understand the clinical course and prognosis of the affected patients. At the time of biopsy or first clinical evaluation, the mean age was 31 years (median: 35 years; range: 1 - 72 years). Hematuria was present in 33 patients (97.1%) and 19 (55.9%) patients had proteinuria. There were 6 (17.6%) patients with hearing loss, 4 (11.8%) with ocular lesions, and 11 (32.4%) with hypertension. Twenty-three (67.6%) patients had proteinuria at follow-up, and 5 (14.7%) patients with the median age of 48 years (range: 27-55) progressed to kidney failure, started dialysis, or underwent kidney transplantation. Of the 13 patients who underwent kidney biopsy, 4 (30.8%) developed focal segmental glomerulosclerosis (FSGS), and 8 (66.7%) showed lamellation of the GBM, including all patients with FSGS. It is essential to conduct a detailed analysis of each collagen type IV genetic variant to optimize the prognosis and therapeutic approach for affected patients.
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Affiliation(s)
- Matija Horaček
- Institute of Pathology, School of Medicine, University of Zagreb, Zagreb, Croatia
| | - Tamara Nikuševa Martić
- Department of Medical Biology and Genetics, School of Medicine, University of Zagreb, Zagreb, Croatia,Correspondence to Tamara Nikuševa Martić:
| | - Petar Šenjug
- Department of Nephropatology and Electron Microscopy, Dubrava University Hospital, Zagreb, Croatia
| | | | - Maja Oroz
- Department of Gynecology and Obstetrics, Clinical Hospital “Sveti Duh”, Zagreb, Croatia
| | - Sania Kuzmac
- Clinical Department of Pathology and Cytology, University Hospital Centre Zagreb, Zagreb, Croatia
| | - Dragan Klarić
- Department of Nephrology, General Hospital Zadar, Zadar, Croatia
| | | | - Marijan Saraga
- Department of Pediatrics, University Hospital Split, Split, Croatia
| | - Danko Milošević
- Department of Pediatrics, University Hospital Centre Zagreb, Zagreb, Croatia
| | - Danica Batinić
- Pediatric ordination dr. Danica Batinić, Zagreb, Croatia
| | - Marijana Ćorić
- Institute of Pathology, School of Medicine, University of Zagreb, Zagreb, Croatia,Clinical Department of Pathology and Cytology, University Hospital Centre Zagreb, Zagreb, Croatia
| | - Frane Paić
- Department of Medical Biology and Genetics, School of Medicine, University of Zagreb, Zagreb, Croatia,Laboratory for Epigenetics and Molecular Medicine, School of Medicine, University of Zagreb, Zagreb, Croatia
| | - Danica Galešić Ljubanović
- Institute of Pathology, School of Medicine, University of Zagreb, Zagreb, Croatia,Department of Nephropatology and Electron Microscopy, Dubrava University Hospital, Zagreb, Croatia
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Novel and Founder Pathogenic Variants in X-Linked Alport Syndrome Families in Greece. Genes (Basel) 2022; 13:genes13122203. [PMID: 36553470 PMCID: PMC9778032 DOI: 10.3390/genes13122203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 11/08/2022] [Accepted: 11/18/2022] [Indexed: 11/27/2022] Open
Abstract
Alport syndrome (AS) is the most frequent monogenic inherited glomerulopathy and is also genetically and clinically heterogeneous. It is caused by semi-dominant pathogenic variants in the X-linked COL4A5 (NM_000495.5) gene or recessive variants in the COL4A3/COL4A4 (NM_000091.4/NM_000092.4) genes. The disease manifests in early childhood with persistent microhematuria and can progress to proteinuria and kidney failure in adolescence or early adulthood if left untreated. On biopsy, pathognomonic features include alternate thinning, thickening and lamellation of the glomerular basement membrane (GBM), in the presence of podocyte foot process effacement. Although previous studies indicate a prevalence of AS of about 1/50,000, a recent publication reported a predicted rate of pathogenic COL4A5 variants of 1/2320. We herewith present 98 patients (40 M/58 F) from 26 Greek families. We are selectively presenting the families segregating the X-linked form of AS with pathogenic variants in the COL4A5 gene. We found 21 different pathogenic variants, 12 novel: eight glycine and one proline substitutions in the collagenous domain, one cysteine substitution in the NC1 domain, two premature termination of translation codons, three splicing variants, one 5-bp insertion/frameshift variant, one indel-frameshift variant and four gross deletions. Notably, patients in six families we describe here and three families we reported previously, carried the COL4A5-p.G624D substitution, a founder defect encountered all over Europe which is hypomorphic with mostly milder symptomatology. Importantly, on several occasions, the correct genetic diagnosis reclassified patients as patients with AS, leading to termination of previous immunosuppressive/cyclosporine A therapy and a switch to angiotensin converting enzyme inhibitors (ACEi). With the understanding that all 98 patients span a wide range of ages from infancy to late adulthood, 15 patients (11 M/4 F) reached kidney failure and 11 (10 M/1 F) received a transplant. The prospects of avoiding lengthy diagnostic investigations and erroneous medications, and the advantage of delaying kidney failure with very early administration of renin-angiotensin-aldosterone system (RAAS) blockade, highlights the importance of timely documentation of AS by genetic diagnosis.
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García-Aznar JM, De la Higuera L, Besada Cerecedo L, Gandiaga NP, Vega AI, Fernández-Fresnedo G, González-Lamuño D. New Insights into Renal Failure in a Cohort of 317 Patients with Autosomal Dominant Forms of Alport Syndrome: Report of Two Novel Heterozygous Mutations in COL4A3. J Clin Med 2022; 11:jcm11164883. [PMID: 36013122 PMCID: PMC9409901 DOI: 10.3390/jcm11164883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 07/27/2022] [Accepted: 08/12/2022] [Indexed: 11/24/2022] Open
Abstract
Alport syndrome (AS) is a clinically and genetically heterogeneous disorder with a wide phenotypic spectrum, onset, and progression. X-linked AS (XLAS) and autosomal recessive AS (ARAS) are severe conditions, whereas the severity of autosomal dominant AS (ADAS) may vary from benign familial hematuria to progressive renal disease with extra-renal manifestations. In this study, we collated information from the literature and analyzed a cohort of 317 patients with ADAS carrying heterozygous disease-causing mutations in COL4A3/4 including four patients from two unrelated families who carried two novel variants in COL4A3. Regarding the age of onset of the disease, 80% of patients presented urinalysis alterations (microhematuria, hematuria, and/or proteinuria) before the age of 40 years. The cumulative probability of suffering adverse renal events was mainly observed between 30 and 70 years, without statistical differences between COL4A3 and COL4A4. We observed statistically significant differences between the sexes in the age of developing ESKD in cases affected by mutations in COL4A3/4 (p value = 0.0097), suggesting that males begin experiencing earlier deterioration of renal function than women. This study supports the importance of follow-up in young patients who harbor pathogenic mutations in COL4A3/4. We update the knowledge of ADAS, highlighting differences in the progression of the disease between males and females.
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Affiliation(s)
| | | | | | - Nerea Paz Gandiaga
- Servicio de Genética, Hospital Universitario Marqués de Valdecilla, 39008 Santander, Spain
| | - Ana Isabel Vega
- Servicio de Genética, Hospital Universitario Marqués de Valdecilla, 39008 Santander, Spain
| | - Gema Fernández-Fresnedo
- Servicio de Nefrología, Hospital Universitario Marqués de Valdecilla, 39008 Santander, Spain
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10
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Aypek H, Krisp C, Lu S, Liu S, Kylies D, Kretz O, Wu G, Moritz M, Amann K, Benz K, Tong P, Hu ZM, Alsulaiman SM, Khan AO, Grohmann M, Wagner T, Müller-Deile J, Schlüter H, Puelles VG, Bergmann C, Huber TB, Grahammer F. Loss of the collagen IV modifier prolyl 3-hydroxylase 2 causes thin basement membrane nephropathy. J Clin Invest 2022; 132:147253. [PMID: 35499085 PMCID: PMC9057608 DOI: 10.1172/jci147253] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 03/16/2022] [Indexed: 01/12/2023] Open
Abstract
The glomerular filtration barrier (GFB) produces primary urine and is composed of a fenestrated endothelium, a glomerular basement membrane (GBM), podocytes, and a slit diaphragm. Impairment of the GFB leads to albuminuria and microhematuria. The GBM is generated via secreted proteins from both endothelial cells and podocytes and is supposed to majorly contribute to filtration selectivity. While genetic mutations or variations of GBM components have been recently proposed to be a common cause of glomerular diseases, pathways modifying and stabilizing the GBM remain incompletely understood. Here, we identified prolyl 3-hydroxylase 2 (P3H2) as a regulator of the GBM in an a cohort of patients with albuminuria. P3H2 hydroxylates the 3' of prolines in collagen IV subchains in the endoplasmic reticulum. Characterization of a P3h2ΔPod mouse line revealed that the absence of P3H2 protein in podocytes induced a thin basement membrane nephropathy (TBMN) phenotype with a thinner GBM than that in WT mice and the development of microhematuria and microalbuminuria over time. Mechanistically, differential quantitative proteomics of the GBM identified a significant decrease in the abundance of collagen IV subchains and their interaction partners in P3h2ΔPod mice. To our knowledge, P3H2 protein is the first identified GBM modifier, and loss or mutation of P3H2 causes TBMN and focal segmental glomerulosclerosis in mice and humans.
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Affiliation(s)
| | - Christoph Krisp
- Institute of Clinical Chemistry and Laboratory Medicine, Mass Spectrometric Proteomics Group, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Shun Lu
- III. Department of Medicine and
| | | | | | | | | | - Manuela Moritz
- Institute of Clinical Chemistry and Laboratory Medicine, Mass Spectrometric Proteomics Group, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Kerstin Amann
- Department of Nephropathology, Institute of Pathology and
| | - Kerstin Benz
- Department of Pediatrics, University of Erlangen, Erlangen, Germany
| | - Ping Tong
- Department of Ophthalmology, The Second Xiangya Hospital and
| | - Zheng-mao Hu
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, China
| | | | - Arif O. Khan
- Eye Institute, Cleveland Clinic Abu Dhabi, Abu Dhabi, United Arab Emirates.,Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine of Case Western University, Cleveland, Ohio, USA
| | - Maik Grohmann
- Medizinische Genetik Mainz, Limbach Genetics, Mainz, Germany
| | - Timo Wagner
- Medizinische Genetik Mainz, Limbach Genetics, Mainz, Germany
| | - Janina Müller-Deile
- Department of Nephrology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Hartmut Schlüter
- Institute of Clinical Chemistry and Laboratory Medicine, Mass Spectrometric Proteomics Group, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | - Carsten Bergmann
- Medizinische Genetik Mainz, Limbach Genetics, Mainz, Germany.,Department of Medicine IV, Faculty of Medicine, Medical Center-University of Freiburg, Freiburg, Germany
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11
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Altun I, Saygılı S, Canpolat N, Özlük Y, Hürdoğan Ö, Yeşil G, Çalışkan S, Sever L. Strong mesangial IgA staining-does it always refer to IgA nephropathy in a patient with proteinuria and hematuria? Answers. Pediatr Nephrol 2021; 36:2043-2045. [PMID: 33459929 DOI: 10.1007/s00467-020-04899-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Accepted: 12/01/2020] [Indexed: 01/28/2023]
Affiliation(s)
- Ilayda Altun
- Department of Pediatrics, Cerrahpasa Faculty of Medicine, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Seha Saygılı
- Department of Pediatric Nephrology, Cerrahpasa Faculty of Medicine, Istanbul University-Cerrahpasa, Istanbul, Turkey.
| | - Nur Canpolat
- Department of Pediatric Nephrology, Cerrahpasa Faculty of Medicine, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Yasemin Özlük
- Department of Pathology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Özge Hürdoğan
- Department of Pathology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Gözde Yeşil
- Department of Medical Genetics, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Salim Çalışkan
- Department of Pediatric Nephrology, Cerrahpasa Faculty of Medicine, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Lale Sever
- Department of Pediatric Nephrology, Cerrahpasa Faculty of Medicine, Istanbul University-Cerrahpasa, Istanbul, Turkey
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12
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Furlano M, Martínez V, Pybus M, Arce Y, Crespí J, Venegas MDP, Bullich G, Domingo A, Ayasreh N, Benito S, Lorente L, Ruíz P, Gonzalez VL, Arlandis R, Cabello E, Torres F, Guirado L, Ars E, Torra R. Clinical and Genetic Features of Autosomal Dominant Alport Syndrome: A Cohort Study. Am J Kidney Dis 2021; 78:560-570.e1. [PMID: 33838161 DOI: 10.1053/j.ajkd.2021.02.326] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Accepted: 02/14/2021] [Indexed: 12/15/2022]
Abstract
RATIONALE & OBJECTIVE Alport syndrome is a common genetic kidney disease accounting for approximately 2% of patients receiving kidney replacement therapy (KRT). It is caused by pathogenic variants in the gene COL4A3, COL4A4, or COL4A5. The aim of this study was to evaluate the clinical and genetic spectrum of patients with autosomal dominant Alport syndrome (ADAS). STUDY DESIGN Retrospective cohort study. SETTING & PARTICIPANTS 82 families (252 patients) with ADAS were studied. Clinical, genetic, laboratory, and pathology data were collected. OBSERVATIONS A pathogenic DNA variant in COL4A3 was identified in 107 patients (35 families), whereas 133 harbored a pathogenic variant in COL4A4 (43 families). Digenic/complex inheritance was observed in 12 patients. Overall, the median kidney survival was 67 (95% CI, 58-73) years, without significant differences across sex (P=0.8), causative genes (P=0.6), or type of variant (P=0.9). Microhematuria was the most common kidney manifestation (92.1%), and extrarenal features were rare. Findings on kidney biopsies ranged from normal to focal segmental glomerulosclerosis. The slope of estimated glomerular filtration rate change was-1.46 (-1.66 to-1.26) mL/min/1.73m2 per year for the overall group, with no significant differences between ADAS genes (P=0.2). LIMITATIONS The relatively small size of this series from a single country, potentially limiting generalizability. CONCLUSIONS Patients with ADAS have a wide spectrum of clinical presentations, ranging from asymptomatic to kidney failure, a pattern not clearly related to the causative gene or type of variant. The diversity of ADAS phenotypes contributes to its underdiagnosis in clinical practice.
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Affiliation(s)
- Mónica Furlano
- Inherited Kidney Diseases, Nephrology Department, Fundació Puigvert, Instituto de Investigaciones Biomédicas Sant Pau, Medicine Department-Universitat Autónoma de Barcelona, Red de Investigación Renal, Instituto de Investigación Carlos III, Barcelona, Spain
| | - Victor Martínez
- Nephrology Department, Hospital Clínico Universitario Virgen de la Arrixaca, Murcia, Spain
| | - Marc Pybus
- Molecular Biology Laboratory, Fundació Puigvert, Instituto de Investigaciones Biomédicas Sant Pau, Universitat Autónoma de Barcelona, Red de Investigación Renal, Instituto de Investigación Carlos III, Barcelona, Spain
| | - Yolanda Arce
- Department of Pathology, Fundació Puigvert, Instituto de Investigaciones Biomédicas Sant Pau, Universitat Autónoma de Barcelona, Red de Investigación Renal, Instituto de Investigación Carlos III, Barcelona, Spain
| | - Jaume Crespí
- Departments of Ophthalmology, Hospital de Sant Pau i la Santa Creu, Instituto de Investigaciones Biomédicas Sant Pau, Universitat Autónoma de Barcelona, Barcelona, Spain
| | - María Del Prado Venegas
- Otolaryngology-Head and Neck Surgery, Hospital de Sant Pau i la Santa Creu, Instituto de Investigaciones Biomédicas Sant Pau, Universitat Autónoma de Barcelona, Barcelona, Spain
| | - Gemma Bullich
- Centre Nacional d'Anàlisi Genómica, Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Andrea Domingo
- Molecular Biology Laboratory, Fundació Puigvert, Instituto de Investigaciones Biomédicas Sant Pau, Universitat Autónoma de Barcelona, Red de Investigación Renal, Instituto de Investigación Carlos III, Barcelona, Spain
| | - Nadia Ayasreh
- Nephrology Department, Fundació Puigvert, Instituto de Investigaciones Biomédicas Sant Pau, Medicine Department-Universitat Autónoma de Barcelona, Red de Investigación Renal, Instituto de Investigación Carlos III, Barcelona, Spain
| | - Silvia Benito
- Nephrology Department, Fundació Puigvert, Instituto de Investigaciones Biomédicas Sant Pau, Medicine Department-Universitat Autónoma de Barcelona, Red de Investigación Renal, Instituto de Investigación Carlos III, Barcelona, Spain
| | - Laura Lorente
- Molecular Biology Laboratory, Fundació Puigvert, Instituto de Investigaciones Biomédicas Sant Pau, Universitat Autónoma de Barcelona, Red de Investigación Renal, Instituto de Investigación Carlos III, Barcelona, Spain
| | - Patricia Ruíz
- Molecular Biology Laboratory, Fundació Puigvert, Instituto de Investigaciones Biomédicas Sant Pau, Universitat Autónoma de Barcelona, Red de Investigación Renal, Instituto de Investigación Carlos III, Barcelona, Spain
| | - Vanesa López Gonzalez
- Genetics Laboratory, Hospital Clínico Universitario Virgen de la Arrixaca, Murcia, Spain
| | - Rosa Arlandis
- Nephrology Department, Hospital General de la Palma, Islas Canarias, Spain
| | - Elisa Cabello
- Nephrology Department, Hospital General Universitario de Castellón, Castellón de la Plana, Spain
| | - Ferran Torres
- Biostatistics Unit, Faculty of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain; Medical Statistics Core Facility, Institut d'Investigacions Biomèdiques August Pi i Sunyer, Hospital Clinic de Barcelona, Barcelona, Spain
| | - Lluis Guirado
- Nephrology Department, Fundació Puigvert, Instituto de Investigaciones Biomédicas Sant Pau, Medicine Department-Universitat Autónoma de Barcelona, Red de Investigación Renal, Instituto de Investigación Carlos III, Barcelona, Spain
| | - Elisabet Ars
- Molecular Biology Laboratory, Fundació Puigvert, Instituto de Investigaciones Biomédicas Sant Pau, Universitat Autónoma de Barcelona, Red de Investigación Renal, Instituto de Investigación Carlos III, Barcelona, Spain.
| | - Roser Torra
- Inherited Kidney Diseases, Nephrology Department, Fundació Puigvert, Instituto de Investigaciones Biomédicas Sant Pau, Medicine Department-Universitat Autónoma de Barcelona, Red de Investigación Renal, Instituto de Investigación Carlos III, Barcelona, Spain.
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13
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Matthaiou A, Poulli T, Deltas C. Prevalence of clinical, pathological and molecular features of glomerular basement membrane nephropathy caused by COL4A3 or COL4A4 mutations: a systematic review. Clin Kidney J 2020; 13:1025-1036. [PMID: 33391746 PMCID: PMC7769542 DOI: 10.1093/ckj/sfz176] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 11/06/2019] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Patients heterozygous for COL4A3 or COL4A4 mutations show a wide spectrum of disease, extending from familial isolated microscopic haematuria, as a result of thin basement membranes (TBMs), to autosomal dominant Alport syndrome (ADAS) and end-stage renal disease (ESRD). Many patients are mentioned in the literature under the descriptive diagnosis of TBM nephropathy (TBMN), in which case it actually describes a histological finding that represents the carriers of autosomal recessive Alport syndrome (ARAS), a severe glomerulopathy, as most patients reach ESRD at a mean age of 25 years. METHODS We performed a systematic literature review for patients with heterozygous COL4A3/A4 mutations with the aim of recording the spectrum and frequency of pathological features. We searched three databases (PubMed, Embase and Scopus) using the keywords 'Autosomal Dominant Alport Syndrome' OR 'Thin Basement Membrane Disease' OR 'Thin Basement Membrane Nephropathy'. We identified 48 publications reporting on 777 patients from 258 families. RESULTS In total, 29% of the patients developed chronic kidney disease (CKD) and 15.1% reached ESRD at a mean age of 52.8 years. Extrarenal features and typical Alport syndrome (AS) findings had a low prevalence in patients as follows: hearing loss, 16%; ocular lesions, 3%; basement membrane thickening, 18.4%; and podocyte foot process effacement, 6.9%. Data for 76 patients from 54 families emphasize extensive inter- and intrafamilial heterogeneity, with age at onset of ESRD ranging between 21 and 84 years (mean 52.8). CONCLUSIONS The analysis enabled a comparison of the clinical course of patients with typical ARAS or X-linked AS with those with heterozygous COL4A mutations diagnosed with TBMN or ADAS. Despite the consequence of a potential ascertainment bias, an important outcome is that TBM poses a global high risk of developing severe CKD, over a long follow-up, with a variable spectrum of other findings. The results are useful to practicing nephrologists for better evaluation of patients.
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Affiliation(s)
| | | | - Constantinos Deltas
- Molecular Medicine Research Center and Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
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14
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Compound Mutations of the COL4A3 including a Novel Allele Identified in a Patient with Alport Syndrome. BIOMED RESEARCH INTERNATIONAL 2020; 2020:1626378. [PMID: 33524082 PMCID: PMC7673930 DOI: 10.1155/2020/1626378] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 10/08/2020] [Accepted: 10/19/2020] [Indexed: 11/17/2022]
Abstract
Alport syndrome (AS) is a hereditary nephropathy which is characterized by molecular abnormalities in collagen IV. Here, we report compound mutations of the COL4A3 gene including a novel allele identified in a patient with Alport syndrome. The patient was a 25-year-old Chinese woman. She has a history of proteinuria and hematuria with cleft lip and palate. The pathologic results were consistent with Alport syndrome. The patient received ACEI treatment but did not respond well to the treatment. Sequencing results revealed that the patient carried two heterozygous mutations in the COL4A3 gene, including a known mutation (c.4243G>C, p.G1415R), which was inherited from her father, and a previously undescribed allele (c.4216G>A, p.G1406R) inherited from her mother. To date, at least 294 different variants of COL4A3 have been reported according to the Human Gene Mutation Database (HGMD). Identification of c.4216G>A as a new AS-related mutation may contribute to both genetic diagnosis of AS and further functional study of COL4A3.
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15
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Fan LL, Liu L, Luo FM, Du R, Wang CY, Dong Y, Liu JS. A novel heterozygous variant of the COL4A4 gene in a Chinese family with hematuria and proteinuria leads to focal segmental glomerulosclerosis and chronic kidney disease. Mol Genet Genomic Med 2020; 8:e1545. [PMID: 33159707 PMCID: PMC7767549 DOI: 10.1002/mgg3.1545] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 09/14/2020] [Accepted: 10/16/2020] [Indexed: 01/15/2023] Open
Abstract
Background Focal segmental glomerulosclerosis (FSGS), as the frequent primary glomerular diseases in adults, accounts for symptomless proteinuria or nephrotic syndrome with or without renal insufficiency. As the crucial lesion of chronic kidney disease (CKD), accumulating evidence from recent studies show that mutations in Collagen‐related genes may be responsible for FSGS. The aim of this study was to identify the genetic lesion of a Chinese family with FSGS and CKD. Methods In this study, we recruited a Han‐Chinese family with unexplained high serum creatinine, hematuria, and proteinuria. Further renal biopsy and renal pathology indicated the diagnosis of FSGS in the proband. Whole‐exome sequencing and Sanger sequencing were employed to explore the pathogenic mutation of this family. Results A novel heterozygous mutation (NM_000092 c.2030G>A, p.G677D) of the collagen type IV alpha‐4 gene (COL4A4) was detected. Co‐segregation analysis revealed that the novel mutation was carried by all the five affected individuals and absent in other healthy members as well as in our 200 local control cohorts. Bioinformatics predication indicated that this novel mutation was pathogenic and may disrupt the structure and function of type IV collagen. Simultaneously, this variant is located in an evolutionarily conserved site of COL4A4 protein. Conclusion Here, we identified a novel mutation of COL4A4 in a family with FSGS and CKD. Our study expanded the variants spectrum of the COL4A4 gene and contributed to the genetic counseling and prenatal genetic diagnosis of the family. In addition, we also recommended the new classification of collagen IV nephropathies, which may be a benefit to the diagnosis, target drug treatment, and management of patients with COL4A3/COL4A4 mutations.
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Affiliation(s)
- Liang-Liang Fan
- Department of Nephrology, The Third Xiangya Hospital of Central South University, Changsha, China.,Department of Cell Biology, The School of Life Sciences, Central South University, Changsha, China.,Hunan Key Laboratory of Animal for Human Disease, School of Life Sciences, Central South University, Changsha, China
| | - Lv Liu
- Department of Respiratory Medicine, Diagnosis and Treatment Center of Respiratory Disease, the Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Fang-Mei Luo
- Department of Cell Biology, The School of Life Sciences, Central South University, Changsha, China.,Hunan Key Laboratory of Animal for Human Disease, School of Life Sciences, Central South University, Changsha, China
| | - Ran Du
- Department of Cell Biology, The School of Life Sciences, Central South University, Changsha, China.,Hunan Key Laboratory of Animal for Human Disease, School of Life Sciences, Central South University, Changsha, China
| | - Chen-Yu Wang
- Department of Cell Biology, The School of Life Sciences, Central South University, Changsha, China.,Hunan Key Laboratory of Animal for Human Disease, School of Life Sciences, Central South University, Changsha, China
| | - Yi Dong
- Department of Cell Biology, The School of Life Sciences, Central South University, Changsha, China.,Hunan Key Laboratory of Animal for Human Disease, School of Life Sciences, Central South University, Changsha, China
| | - Ji-Shi Liu
- Department of Nephrology, The Third Xiangya Hospital of Central South University, Changsha, China
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16
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Daso RE, Banerjee IA. Self-Assembled Peptide-Based Biocomposites for Near-Infrared Light Triggered Drug Release to Tumor Cells. Biotechnol J 2020; 15:e2000128. [PMID: 32845561 DOI: 10.1002/biot.202000128] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 07/21/2020] [Indexed: 11/11/2022]
Abstract
Peptide-based nanomaterials are increasingly gaining popularity due to their specificity, biocompatibility, and biodegradability. In this work, a new multi-layered peptide-based biocomposite for targeting MCF-7 breast cancer cells is developed. The amphipathic Fluorenylmethyloxycarbonyl (Fmoc)-Leu-Ser peptide is synthesized, which is conjugated to a tumor-targeting peptide sequence Gly-Cys-Gly-Asn-Ser to form Fmoc-L-S-G-C-G-N-S (FLS) assemblies. To the FLS assemblies, gold nanorods are then attached to develop drug delivery vehicles (DDVs). The DDVs are entrapped with the anti-cancer drug fulvestrant. Entrapment efficiency is found to be 50.6%. Release studies indicate that irradiating the gold nanorod bound DDVs at NIR wavelength (785 nm) increases drug release by fourfold compared to assemblies that are not irradiated. These results also show higher cytotoxicity and lower cell invasion due to photo-triggered drug release. Furthermore, distinct actin cytoskeletal changes are observed. Such novel peptide-based gold nanorod bound DDVs demonstrate potential in dual targeting of MCF-7 breast cancer cells.
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Affiliation(s)
- Rachel E Daso
- Department of Chemistry, Fordham University, 441 E. Fordham Road, Bronx, NY, 10458, USA
| | - Ipsita A Banerjee
- Department of Chemistry, Fordham University, 441 E. Fordham Road, Bronx, NY, 10458, USA
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17
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Demir E, Caliskan Y. Variations of type IV collagen-encoding genes in patients with histological diagnosis of focal segmental glomerulosclerosis. Pediatr Nephrol 2020; 35:927-936. [PMID: 31254113 DOI: 10.1007/s00467-019-04282-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 05/01/2019] [Accepted: 05/31/2019] [Indexed: 01/07/2023]
Abstract
Focal segmental glomerulosclerosis (FSGS), an important cause of end-stage kidney disease (ESKD), covers a spectrum of clinicopathological syndromes sharing a common glomerular lesion, based on an injury of podocytes caused by diverse insults to glomeruli. Although it is well expressed in many reports that the term FSGS is not useful and applicable to a single disease, particularly in genetic studies, FSGS continues to be used as a single clinical diagnosis. Distinguishing genetic forms of FSGS is important for the treatment and overall prognosis because secondary forms of FSGS, produced by rare pathogenic variations in podocyte genes, are not good candidates for immunosuppressive treatment. Over the past decade, several next generation sequencing (NGS) methods have been used to investigate the patients with steroid resistance nephrotic syndrome (SRNS) or FSGS. Pathogenic variants in COL4A3, COL4A4, or COL4A5 genes have been frequently identified in patients with histologic diagnosis of FSGS. The contribution of these mostly heterozygous genetic variations in FSGS pathogenesis and the clinical course of patients with these variations have not been well characterized. This review emphasizes the importance of appropriate approach in selection and diagnosis of cases and interpretation of the genetic data in these studies and suggests a detailed review of existing clinical variant databases using newly available population genetic data.
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Affiliation(s)
- Erol Demir
- Division of Nephrology, Department of Internal Medicine, Istanbul School of Medicine, Istanbul University, Capa, Fatih, 34093, Istanbul, Turkey
| | - Yasar Caliskan
- Division of Nephrology, Department of Internal Medicine, Istanbul School of Medicine, Istanbul University, Capa, Fatih, 34093, Istanbul, Turkey.
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18
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Torra R, Furlano M. New therapeutic options for Alport syndrome. Nephrol Dial Transplant 2020; 34:1272-1279. [PMID: 31190059 DOI: 10.1093/ndt/gfz131] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 05/31/2019] [Indexed: 12/12/2022] Open
Abstract
Alport syndrome (AS) is the most frequent inherited kidney disease after autosomal dominant polycystic kidney disease. It has three different patterns of inheritance-autosomal dominant, autosomal recessive and X-linked-which in part explains the wide spectrum of disease, ranging from isolated microhaematuria to end-stage renal disease early in life. The search for a treatment for AS is being pursued vigorously, not only because of the obvious unmet need but also because AS is a rare disease and any drug approved will have an orphan drug designation with its various benefits. Moreover, AS patients are quite young with very few comorbidities, which facilitates clinical trials. This review identifies the particularities of each pattern of inheritance but focuses mainly on new drugs or therapeutic targets for the disease. Most treatment-related investigations are directed not at the main abnormality in AS, namely collagen IV composition, but rather at the associated inflammation and fibrosis. Thus, AS may serve as a proof of concept for numerous drugs of potential value in many diseases that cause chronic kidney disease.
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Affiliation(s)
- Roser Torra
- Inherited Renal Disorders, Nephrology Department, Fundació Puigvert, REDINREN, IIB Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Mónica Furlano
- Inherited Renal Disorders, Nephrology Department, Fundació Puigvert, REDINREN, IIB Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain
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19
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Endoplasmic reticulum stress and proteasome pathway involvement in human podocyte injury with a truncated COL4A3 mutation. Chin Med J (Engl) 2020; 132:1823-1832. [PMID: 31306228 PMCID: PMC6759124 DOI: 10.1097/cm9.0000000000000294] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Background: Collagen type IV (COL4)-related nephropathy includes a variety of kidney diseases that occur with or without extra-renal manifestations caused by COL4A3-5 mutations. Previous studies revealed several novel mutations, including three COL4A3 missense mutations (G619R, G801R, and C1616Y) and the COL4A3 chr:228172489delA c.4317delA p.Thr1440ProfsX87 frameshift mutation that resulted in a truncated NC1 domain (hereafter named COL4A3 c.4317delA); however, the mutation mechanisms that lead to podocyte injury remain unclear. This study aimed to further explore the mutation mechanisms that lead to podocyte injury. Methods: Wild-type (WT) and four mutant COL4A3 segments were constructed into a lentiviral plasmid, then stably transfected into human podocytes. Real-time polymerase chain reaction and Western blotting were applied to detect endoplasmic reticulum stress (ERS)- and apoptosis-related mRNA and protein levels. Then, human podocytes were treated with MG132 (a proteasome inhibitor) and brefeldin A (a transport protein inhibitor). The human podocyte findings were verified by the establishment of a mus-Col4a3 knockout mouse monoclonal podocyte using clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) technology. Results: Our data showed that COL4A3 mRNA was significantly overexpressed in the lentivirus stably transfected podocytes. Moreover, the COL4A3 protein level was significantly increased in all groups except the COL4A3 c.4317delA group. Compared to the other test groups, the COL4A3 c.4317delA group showed excessive ERS and apoptosis. Podocytes treated with MG132 showed remarkably increased intra-cellular expression of the COL4A3 c.4317delA mutation. MG132 intervention improved higher ERS and apoptosis levels in the COL4A3 c.4317delA group. Mouse monoclonal podocytes with COL4A3 chr:82717932insA c.4852insA p.Arg1618ThrfsX4 were successfully acquired; this NC1-truncated mutation suggested a higher level of ERS and relatively remarkable level of apoptosis compared to that of the WT group. Conclusions: We demonstrated that excessive ERS and ERS-induced apoptosis were involved in the podocyte injury caused by the NC1-truncated COL4A3 mutation. Furthermore, proteasome pathway intervention might become a potential treatment for collagen type IV-related nephropathy caused by a severely truncated COL4A3 mutation.
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Genetic studies of focal segmental glomerulosclerosis: a waste of scientific time? Pediatr Nephrol 2020; 35:9-16. [PMID: 30591974 PMCID: PMC6901409 DOI: 10.1007/s00467-018-4161-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 11/27/2018] [Accepted: 11/28/2018] [Indexed: 12/21/2022]
Abstract
Many genetic causes of focal segmental glomerulosclerosis (FSGS) have been described. A paradox is that the science in the molecular biology, which generally appears of high quality, is not mirrored by a similarly critical analysis of the renal pathology. FSGS has been applied to such a wide range of conditions that it can reasonably be said to have no useful meaning. Attempts to refine the term have been largely ignored. Study of 252 papers on genetic causes of FSGS found various clinical features. Many papers took the reported diagnosis without question. Few papers reported a pathological review, almost half reported FSGS and up to six other conditions caused by any particular gene, some reported FSGS with recognisable glomerular disorders, over 80% did not apply the Columbia classification, and in nearly all with photomicrographs, the images were not useful for refinement of FSGS. Some workers commented on a lack of genotype-phenotype correlation. One reason is a disregard of the principle that scientific investigation requires an unambiguous definition of the condition studied, to allow others to replicate or refute the findings. Genetic studies of FSGS should use a similarly rigorous approach to renal pathology to that used in molecular biology.
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Clinicopathological Implications of Proteinuria after Long-Term Isolated Hematuria due to Thin Basement Membrane Nephropathy and Focal Segmental Glomerulosclerosis. Case Rep Nephrol 2019; 2019:1627392. [PMID: 31976098 PMCID: PMC6959157 DOI: 10.1155/2019/1627392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 10/02/2019] [Accepted: 10/25/2019] [Indexed: 11/17/2022] Open
Abstract
A 45-year-old obese man presented with persistent hematuria for 21 years. At the age of 37, he developed hypertension and proteinuria which later increased up to 1.6 g/g creatinine. Kidney biopsy revealed thin basement membrane nephropathy (TBMN) and focal segmental glomerulosclerosis (FSGS), which explained his urinary abnormalities. Although a subgroup of TBMN can be complicated by FSGS, his FSGS was associated with obesity because of its histological features. Reduction of body weight and increasing a dose of angiotensin-receptor blocker could transiently reduce the amount of proteinuria. Clinicopathological implications of proteinuria after long-term hematuria by TBMN and FSGS were further discussed.
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Endoplasmic reticulum stress and monogenic kidney diseases in precision nephrology. Pediatr Nephrol 2019; 34:1493-1500. [PMID: 30099615 PMCID: PMC6370526 DOI: 10.1007/s00467-018-4031-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 06/22/2018] [Accepted: 07/20/2018] [Indexed: 01/05/2023]
Abstract
The advent of next-generation sequencing (NGS) in recent years has led to a rapid discovery of novel or rare genetic variants in human kidney cell genes, which is transforming the risk assessment, diagnosis, and treatment of kidney disease. Mutations may lead to protein misfolding, disruption of protein trafficking, and endoplasmic reticulum (ER) retention. An imbalance between the load of misfolded proteins and the folding capacity of the ER causes ER stress and unfolded protein response. Mutations in nephrin (NPHS1), podocin (NPHS2), laminin β2 (LAMB2), and α-actinin-4 (ACTN4) have been shown to induce ER stress in HEK293 cells and podocytes in hereditary nephrotic syndromes; various founder mutations in collagen IV α chains (COL4A) have been demonstrated to activate podocyte ER stress in collagen IV nephropathies; and mutations in uromodulin (UMOD) have been reported to trigger tubular ER stress in autosomal dominant tubulointerstitial kidney disease. Meanwhile, ER resident protein SEC63 may modify disease severity in autosomal dominant polycystic kidney disease. These findings underscore the importance of ER stress in the pathogenesis of monogenic kidney disease. Recently, we have identified mesencephalic astrocyte-derived neurotrophic factor (MANF) and cysteine-rich with EGF-like domains 2 (CRELD2) as urinary ER stress biomarkers in ER stress-mediated kidney diseases.
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Sun H, Yu X, Li S, Xu H, Yang J, Yi T, Han P, Shao M. A novel mutation in a Chinese family with autosomal recessive Alport syndrome: a case report. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2019; 12:3565-3569. [PMID: 31934206 PMCID: PMC6949818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 08/26/2019] [Indexed: 06/10/2023]
Abstract
Alport syndrome (AS) is a familial hereditary nephropathy which is characterized by molecular abnormalities in Collagen IV a345. As more gene mutations are discovered, it has been reported that autosomal recessive disease accounts for a smaller proportion (about 4%) of AS patients than previously recognized. We report here a novel mutation in COL4A4 in a Chinese family with autosomal recessive AS. Patient 1 was a 24-year-old Chinese man. He and his brother (patient 2) had a history of proteinuria and hematuria with renal dysfunction and sensorineural deafness. Pathologic findings were consistent with Alport syndrome, and genetic analysis revealed that both patients had two heterozygous mutations, c.1423 G>T (p.Gly475Cys) in EX21/CDS20 and c.735 G>A (p.Pro245Pro) in EX12/CDS11, and that each mutation originated from their mother or father who were carriers for one of these two mutations. Both patients showed similar results by laboratory examination and histopathologic assessment. Patient 1 received ACEI treatment and ran a stable clinical course, whereas patient 2 refused ACEI treatment and had progressive deterioration of renal function. This is the first report of a novel mutation in the collagen domain of COL4A4 gene. The results add to the spectrum of mutations in COL4A4 of Alport syndrome.
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Affiliation(s)
- Huili Sun
- Department of Nephrology, Shenzhen Traditional Chinese Medicine Hospital, The Fourth Clinical Medical College of Guangzhou University of Chinese MedicineShenzhen 518033, Guangdong, China
| | - Xuewen Yu
- Department of Pathology, Shenzhen Traditional Chinese Medicine Hospital, The Fourth Clinical Medical College of Guangzhou University of Chinese MedicineShenzhen 518033, Guangdong, China
| | - Shunmin Li
- Department of Nephrology, Shenzhen Traditional Chinese Medicine Hospital, The Fourth Clinical Medical College of Guangzhou University of Chinese MedicineShenzhen 518033, Guangdong, China
| | - Hua Xu
- Department of Pathology, Shenzhen Traditional Chinese Medicine Hospital, The Fourth Clinical Medical College of Guangzhou University of Chinese MedicineShenzhen 518033, Guangdong, China
| | - Jun Yang
- Department of Nephrology, Shenzhen Traditional Chinese Medicine Hospital, The Fourth Clinical Medical College of Guangzhou University of Chinese MedicineShenzhen 518033, Guangdong, China
| | - Tiegang Yi
- Department of Nephrology, Shenzhen Traditional Chinese Medicine Hospital, The Fourth Clinical Medical College of Guangzhou University of Chinese MedicineShenzhen 518033, Guangdong, China
| | - Pengxun Han
- Department of Nephrology, Shenzhen Traditional Chinese Medicine Hospital, The Fourth Clinical Medical College of Guangzhou University of Chinese MedicineShenzhen 518033, Guangdong, China
| | - Mumin Shao
- Department of Pathology, Shenzhen Traditional Chinese Medicine Hospital, The Fourth Clinical Medical College of Guangzhou University of Chinese MedicineShenzhen 518033, Guangdong, China
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Akihisa T, Sato M, Wakayama Y, Taneda S, Horita S, Hirose O, Makabe S, Kataoka H, Mori T, Sohara E, Uchida S, Nitta K, Mochizuki T. Glomerular Basement Membrane Protein Expression and the Diagnosis and Prognosis of Autosomal Dominant Alport Syndrome. Kidney Med 2019; 1:391-396. [PMID: 32734219 PMCID: PMC7380416 DOI: 10.1016/j.xkme.2019.06.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Alport syndrome is a hereditary glomerular nephritis associated with hearing loss and eye abnormalities and is classified as X-linked Alport syndrome, autosomal recessive Alport syndrome, and autosomal dominant Alport syndrome. Autosomal dominant Alport syndrome is caused by a mutation in the gene encoding type IV collagen α3 (α3[IV]); (COL4A3), or α4 (α4[IV]); (COL4A4). Autosomal dominant Alport syndrome progresses more gradually than male X-linked Alport syndrome and autosomal recessive Alport syndrome. Differentiating autosomal dominant Alport syndrome from thin basement membrane nephropathy, which shows better kidney prognosis, remains challenging. Because autosomal dominant Alport syndrome is linked to a heterozygous mutation, type IV collagen is produced by the wild-type allele, and all α(IV) chains are supposed to be normally expressed. In this study, the pathologic findings of a patient with Alport syndrome with a novel COL4A4 heterozygous nonsense mutation were investigated. We observed weaker staining of α5(IV) in the glomerular basement membrane and enhanced expressions of α2(IV), laminin, and fibronectin, which were assumed to be caused by compensatory mechanisms for lack of enough α3α4α5(IV) expression in the glomerular basement membrane. These findings may be useful not only for differentially diagnosing autosomal dominant Alport syndrome from thin basement membrane nephropathy, but also for determining the extent of progression and predicting kidney prognosis.
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Affiliation(s)
- Taro Akihisa
- Department of Medicine, Tokyo Medical and Dental University, Tokyo, Japan
| | - Masayo Sato
- Department of Medicine, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yoshie Wakayama
- Department of Medicine, Tokyo Medical and Dental University, Tokyo, Japan
| | - Sekiko Taneda
- Division of Pathology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Shigeru Horita
- Clinical Research Division for Polycystic Kidney Disease, Department of Medicine, Kidney Center, Tokyo Women's Medical University, Tokyo Medical and Dental University, Tokyo, Japan
| | - Orie Hirose
- Department of Pathology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Shiho Makabe
- Department of Medicine, Tokyo Medical and Dental University, Tokyo, Japan
| | - Hiroshi Kataoka
- Department of Medicine, Tokyo Medical and Dental University, Tokyo, Japan.,Clinical Research Division for Polycystic Kidney Disease, Department of Medicine, Kidney Center, Tokyo Women's Medical University, Tokyo Medical and Dental University, Tokyo, Japan
| | - Takayasu Mori
- Department of Nephrology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Eisei Sohara
- Department of Nephrology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Shinichi Uchida
- Department of Nephrology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Kosaku Nitta
- Department of Medicine, Tokyo Medical and Dental University, Tokyo, Japan
| | - Toshio Mochizuki
- Department of Medicine, Tokyo Medical and Dental University, Tokyo, Japan.,Clinical Research Division for Polycystic Kidney Disease, Department of Medicine, Kidney Center, Tokyo Women's Medical University, Tokyo Medical and Dental University, Tokyo, Japan
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Hashimoto H, Ohashi N, Tsuji N, Naito Y, Isobe S, Fujikura T, Tsuji T, Kato A, Nozu K, Iijima K, Yasuda H. A case report of thin basement membrane nephropathy accompanied by sporadic glomerulocystic kidney disease. BMC Nephrol 2019; 20:248. [PMID: 31288791 PMCID: PMC6617628 DOI: 10.1186/s12882-019-1451-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 07/03/2019] [Indexed: 11/19/2022] Open
Abstract
Background Thin basement membrane nephropathy (TBMN) is a relatively common disease. Patients typically present with isolated hematuria, which has a good renal prognosis. In contrast, glomerulocystic kidney disease (GCKD) is a rare disease, associated with slow progressive renal dysfunction. To our knowledge, co-occurring diagnosis of TBMN with GCKD has not been reported previously. Case presentation A 30-year old woman was admitted to our hospital for evaluation of hematuria and renal insufficiency. Upon examination, her urinary protein level was 40 mg/day and occult blood in her urine was 2+. The patient’s urinary dysmorphic red blood cell sediment was 30–49/high power field. In contrast, her serum creatinine levels increased from 0.57 mg/dl to 0.86 mg/dl during the previous 2-years, without special events. She suffered from far-sightedness and astigmatism beginning at birth; She had no family history of renal disease. Renal biopsy demonstrated cystic dilatation of the Bowman’s capsule and atrophy of the glomerular tuft. The glomerular basement membrane (GBM) was thin, with an average thickness of 191 nm. Next-generation sequencing was used to evaluate for mutations in COL4A3 and COL4A4, associated with TBMN, and UMOD, MUC1, and SEC61A1, associated with hereditary GCKD. No pathogenic mutations were identified. We thus diagnosed the patient with TBMN coexistent with sporadic GCKD. Conclusion We report the patient diagnosed with TBMN accompanied by sporadic GCKD, based on renal biopsy and genetic testing. Because it is possible that other diseases, such as GCKD, can coexist with TBMN, it is important to consider renal biopsy.
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Affiliation(s)
- Hiroyuki Hashimoto
- Internal Medicine 1, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku Hamamatsu, 431-3192, Japan
| | - Naro Ohashi
- Internal Medicine 1, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku Hamamatsu, 431-3192, Japan.
| | - Naoko Tsuji
- Blood Purification Unit, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku Hamamatsu, 431-3192, Japan
| | - Yoshitaka Naito
- Internal Medicine 1, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku Hamamatsu, 431-3192, Japan
| | - Shinsuke Isobe
- Internal Medicine 1, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku Hamamatsu, 431-3192, Japan
| | - Tomoyuki Fujikura
- Internal Medicine 1, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku Hamamatsu, 431-3192, Japan
| | - Takayuki Tsuji
- Internal Medicine 1, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku Hamamatsu, 431-3192, Japan
| | - Akihiko Kato
- Blood Purification Unit, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku Hamamatsu, 431-3192, Japan
| | - Kandai Nozu
- Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan
| | - Kazumoto Iijima
- Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan
| | - Hideo Yasuda
- Internal Medicine 1, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku Hamamatsu, 431-3192, Japan
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Park SJ, Kim Y, Yang SM, Henderson MJ, Yang W, Lindahl M, Urano F, Chen YM. Discovery of endoplasmic reticulum calcium stabilizers to rescue ER-stressed podocytes in nephrotic syndrome. Proc Natl Acad Sci U S A 2019; 116:14154-14163. [PMID: 31235574 PMCID: PMC6628787 DOI: 10.1073/pnas.1813580116] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Emerging evidence has established primary nephrotic syndrome (NS), including focal segmental glomerulosclerosis (FSGS), as a primary podocytopathy. Despite the underlying importance of podocyte endoplasmic reticulum (ER) stress in the pathogenesis of NS, no treatment currently targets the podocyte ER. In our monogenic podocyte ER stress-induced NS/FSGS mouse model, the podocyte type 2 ryanodine receptor (RyR2)/calcium release channel on the ER was phosphorylated, resulting in ER calcium leak and cytosolic calcium elevation. The altered intracellular calcium homeostasis led to activation of calcium-dependent cytosolic protease calpain 2 and cleavage of its important downstream substrates, including the apoptotic molecule procaspase 12 and podocyte cytoskeletal protein talin 1. Importantly, a chemical compound, K201, can block RyR2-Ser2808 phosphorylation-mediated ER calcium depletion and podocyte injury in ER-stressed podocytes, as well as inhibit albuminuria in our NS model. In addition, we discovered that mesencephalic astrocyte-derived neurotrophic factor (MANF) can revert defective RyR2-induced ER calcium leak, a bioactivity for this ER stress-responsive protein. Thus, podocyte RyR2 remodeling contributes to ER stress-induced podocyte injury. K201 and MANF could be promising therapies for the treatment of podocyte ER stress-induced NS/FSGS.
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Affiliation(s)
- Sun-Ji Park
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - Yeawon Kim
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - Shyh-Ming Yang
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Mark J Henderson
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Wei Yang
- Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110
| | - Maria Lindahl
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland 00014
| | - Fumihiko Urano
- Division of Endocrinology, Metabolism, and Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - Ying Maggie Chen
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110;
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Imafuku A, Nozu K, Sawa N, Hasegawa E, Hiramatsu R, Kawada M, Hoshino J, Tanaka K, Ishii Y, Takaichi K, Fujii T, Ohashi K, Iijima K, Ubara Y. Autosomal dominant form of type IV collagen nephropathy exists among patients with hereditary nephritis difficult to diagnose clinicopathologically. Nephrology (Carlton) 2019; 23:940-947. [PMID: 28704582 PMCID: PMC6767408 DOI: 10.1111/nep.13115] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/10/2017] [Indexed: 01/01/2023]
Abstract
The study revealed that 69% of families with hereditary nephritis that was difficult to diagnose clinicopathologically had heterozygous mutations of COL4A3/A4 (TBMN/ADAS). The finding suggests the importance of genetic testing in appropriate patients. Aim Type IV collagen nephropathies include Alport Syndrome and thin basement membrane nephropathy (TBMN), which are caused by mutations in COL4A3/A4/A5 genes. Recently, reports of patients with heterozygous mutations in COL4A3/A4 have been increasing. The clinical course of these patients has a wide variety, and they are diagnosed as TBMN, autosomal dominant Alport syndrome (ADAS), or familial focal segmental glomerular sclerosis. However, diagnosis, frequency and clinicopathological manifestation of them remains unclear. We tested COL4A3/A4/A5 genes in patients with hereditary nephritis that was difficult to diagnose clinicopathologically, and investigated who should undergo such testing. Methods We performed immunostaining for α5 chain of type IV collagen [α5 (IV)] in 27 patients from 21 families who fitted the following criteria: (i) haematuria and proteinuria (± renal dysfunction); (ii) family history of haematuria, proteinuria, and/or renal dysfunction (autosomal dominant inheritance); (iii) no specific glomerulonephritis; and (iv) thinning, splitting, or lamellation of the glomerular basement membrane (GBM) on electron microscopy. Then we performed genetic testing in 19 patients from 16 families who showed normal α5 (IV) patterns. We conducted a retrospective analysis of their clinicopathological findings. Results Among 16 families, 69% were detected heterozygous mutations in COL4A3/A4, suggesting the diagnosis of TBMN/ADAS. Twenty‐one percent of patients developed end stage renal disease. All patients showed thinning of GBM, which was accompanied by splitting or lamellation in seven patients. Conclusion A considerable fraction of patients with hereditary nephritis that is difficult to diagnose clinicopathologically have TBMN/ADAS. It is important to recognize TBMN/ADAS and perform genetic testing in appropriate patients.
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Affiliation(s)
- Aya Imafuku
- Nephrology Center, Toranomon Hospital, Minato-ku, Japan
| | - Kandai Nozu
- Department of Pediatrics, Kobe University, Kobe, Japan
| | - Naoki Sawa
- Nephrology Center, Toranomon Hospital, Minato-ku, Japan
| | - Eiko Hasegawa
- Nephrology Center, Toranomon Hospital, Minato-ku, Japan
| | | | | | | | - Kiho Tanaka
- Nephrology Center, Toranomon Hospital, Minato-ku, Japan
| | - Yasuo Ishii
- Nephrology Center, Toranomon Hospital, Minato-ku, Japan
| | - Kenmei Takaichi
- Nephrology Center, Toranomon Hospital, Minato-ku, Japan.,Okinaka Memorial Institute for Medical Research, Toranomon Hospital, Minato-ku, Japan
| | - Takeshi Fujii
- Department of Pathology, Toranomon Hospital, Minato-ku, Japan
| | - Kenichi Ohashi
- Department of Pathology, Toranomon Hospital, Minato-ku, Japan.,Department of Pathology, Yokohama City University, Graduate School of Medicine, Yokohama-shi, Japan
| | | | - Yoshifumi Ubara
- Nephrology Center, Toranomon Hospital, Minato-ku, Japan.,Okinaka Memorial Institute for Medical Research, Toranomon Hospital, Minato-ku, Japan
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A Novel Heterozygous Mutation of the COL4A3 Gene Causes a Peculiar Phenotype without Hematuria and Renal Function Impairment in a Chinese Family. DISEASE MARKERS 2019; 2019:8705989. [PMID: 30881523 PMCID: PMC6387717 DOI: 10.1155/2019/8705989] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 01/16/2019] [Accepted: 01/17/2019] [Indexed: 01/15/2023]
Abstract
Mutations in the COL4A3 gene are frequently reported to be associated with various types of hereditary nephropathy. COL4A3 encodes the α3 chain of type IV collagen, which is the main structural protein in the basement membrane. Mutations in this gene are always related to kidney performance, and deafness and ocular lesion have also been reported. In this study, using next-generation sequencing, we investigated the DNA of a family visiting a clinic for hearing loss. A new missense mutation was found in COL4A3 of 5 patients, c.3227C>T (p.P1076L). Based on these results, we predict that the mutation is pathogenic and leads to abnormal collagen IV. Here, we report for the first time on this autosomal dominant syndrome, characterized by hearing loss and eye abnormalities, but without renal damage, in all carriers. Since the oldest patient in the trial was less than 50 years old, however, we recommend that renal examination be reviewed regularly. Our results reveal expansion in the mutation spectrum of the COL4A3 gene and phenotypic spectrum of collagen IV disease. Our study suggests that next-generation sequencing is an economical and effective method and may help in the accurate diagnosis and treatment of these patients.
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Gross O, Hoefele J. Genetische Ursachen und Therapie beim Alport-Syndrom. MED GENET-BERLIN 2019. [DOI: 10.1007/s11825-018-0214-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Zusammenfassung
Bei der Typ IV Kollagen-Erkrankung Alport-Syndrom (AS) handelt es sich um eine progressive hereditäre Nephropathie. Klinische Zeichen sind zunächst Hämaturie und Proteinurie, im weiteren Verlauf kommt es zu einem terminalen Nierenversagen. Zusätzlich werden extrarenale Manifestationen wie Innenohr-Schwerhörigkeit und Augenveränderungen beobachtet. Man unterscheidet drei Erbgänge: 85 % der Fälle sind X-chromosomal, ca. 10 % autosomal und weniger als 5 % digenisch. Ursächlich sind Varianten in den Kollagen Typ IV-Genen COL4A3, COL4A4 (beide autosomal) und COL4A5 (X-chromosomal). Die Symptomatik heterozygoter Anlageträger wurde früher als benigne familiäre Hämaturie bezeichnet. Da Anlageträger jedoch häufig keinen benignen Verlauf zeigen, werden sie inzwischen auch unter der Diagnose „Alport-Syndrom“ geführt.
Der Humangenetiker hat daher beim AS eine wichtige Lotsenfunktion: Bei früher Diagnose ist das AS inzwischen gut behandelbar, wodurch das terminale Nierenversagen um mehrere Jahre hinausgezögert und damit die Lebenserwartung verbessert werden kann. Aufgrund der Therapiemöglichkeiten sollte die (molekulargenetische) Diagnose bei Betroffenen, auch bei heterozygoten Anlageträgern, frühzeitig gestellt werden.
Mit diesem Artikel sollen die genetischen Ursachen des AS, mögliche genetische Einflussfaktoren auf den variablen Phänotyp, die unterschiedlichen Krankheitsstadien, Komplikationen sowie die derzeit zugelassene Behandlung aufgezeigt werden, um eine bestmögliche lebenslange Betreuung des Patienten zu gewährleisten.
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Affiliation(s)
- Oliver Gross
- Aff1 0000 0001 0482 5331 grid.411984.1 Klinik für Nephrologie und Rheumatologie Universitätsmedizin Göttingen Robert-Koch Str. 40 37075 Göttingen Deutschland
| | - Julia Hoefele
- Aff2 Institut für Humangenetik Klinikum rechts der Isar, Technische Universität München Trogerstr. 32 81675 München Deutschland
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Voskarides K, Papagregoriou G, Hadjipanagi D, Petrou I, Savva I, Elia A, Athanasiou Y, Pastelli A, Kkolou M, Hadjigavriel M, Stavrou C, Pierides A, Deltas C. COL4A5 and LAMA5 variants co-inherited in familial hematuria: digenic inheritance or genetic modifier effect? BMC Nephrol 2018; 19:114. [PMID: 29764427 PMCID: PMC5954460 DOI: 10.1186/s12882-018-0906-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 10/25/2017] [Accepted: 01/21/2018] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND About 40-50% of patients with familial microscopic hematuria (FMH) caused by thin basement membrane nephropathy (TBMN) inherit heterozygous mutations in collagen IV genes (COL4A3, COL4A4). On long follow-up, the full phenotypic spectrum of these patients varies a lot, ranging from isolated MH or MH plus low-grade proteinuria to chronic renal failure of variable degree, including end-stage renal disease (ESRD). METHODS Here, we performed Whole Exome Sequencing (WES) in patients of six families, presenting with autosomal dominant FMH, with or without progression to proteinuria and loss of renal function, all previously found negative for severe collagen IV mutations. Hierarchical filtering of the WES data was performed, followed by mutation prediction analysis, Sanger sequencing and genetic segregation analysis. RESULTS In one family with four patients, we found evidence for the contribution of two co-inherited variants in two crucial genes expressed in the glomerular basement membrane (GBM); LAMA5-p.Pro1243Leu and COL4A5-p.Asp654Tyr. Mutations in COL4A5 cause classical X-linked Alport Syndrome, while rare mutations in the LAMA5 have been reported in patients with focal segmental glomerulosclerosis. The phenotypic spectrum of the patients includes hematuria, proteinuria, focal segmental glomerulosclerosis, loss of kidney function and renal cortical cysts. CONCLUSIONS A modifier role of LAMA5 on the background of a hypomorphic Alport syndrome causing mutation is a possible explanation of our findings. Digenic inheritance is another scenario, following the concept that mutations at both loci more accurately explain the spectrum of symptoms, but further investigation is needed under this concept. This is the third report linking a LAMA5 variant with human renal disease and expanding the spectrum of genes involved in glomerular pathologies accompanied by familial hematurias. The cystic phenotype overlaps with that of a mouse model, which carried a Lama5 hypomorphic mutation that caused severely reduced Lama5 protein levels and produced kidney cysts.
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Affiliation(s)
- Konstantinos Voskarides
- Molecular Medicine Research Center, Department of Biological Sciences, University of Cyprus, 1, University Avenue, 2109, Nicosia, Cyprus. .,Medical School, University of Cyprus, Nicosia, Cyprus.
| | - Gregory Papagregoriou
- Molecular Medicine Research Center, Department of Biological Sciences, University of Cyprus, 1, University Avenue, 2109, Nicosia, Cyprus
| | - Despina Hadjipanagi
- Molecular Medicine Research Center, Department of Biological Sciences, University of Cyprus, 1, University Avenue, 2109, Nicosia, Cyprus
| | - Ioanelli Petrou
- Molecular Medicine Research Center, Department of Biological Sciences, University of Cyprus, 1, University Avenue, 2109, Nicosia, Cyprus
| | - Isavella Savva
- Molecular Medicine Research Center, Department of Biological Sciences, University of Cyprus, 1, University Avenue, 2109, Nicosia, Cyprus
| | - Avraam Elia
- Department of Pediatric Nephrology, Archbishop Makarios III Hospital, Nicosia, Cyprus
| | | | | | - Maria Kkolou
- Department of Nephrology, Larnaca General Hospital, Larnaca, Cyprus
| | | | | | - Alkis Pierides
- Molecular Medicine Research Center, Department of Biological Sciences, University of Cyprus, 1, University Avenue, 2109, Nicosia, Cyprus.,Hippocrateon Hospital, Nicosia, Cyprus
| | - Constantinos Deltas
- Molecular Medicine Research Center, Department of Biological Sciences, University of Cyprus, 1, University Avenue, 2109, Nicosia, Cyprus. .,College of Medicine, Qatar University, Doha, Qatar.
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Mutation analysis of COL4A3 and COL4A4 genes in a Chinese autosomal-dominant Alport syndrome family. J Genet 2018; 96:389-392. [PMID: 28674241 DOI: 10.1007/s12041-017-0786-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Autosomal dominant Alport syndrome (ADAS) accounts for 5% of all cases of Alport syndrome (AS), a primary basement membrane disorder arising from mutations in genes encoding the type IV collagen protein family.Mutations in COL4A3 and COL4A4 genes were reported to be associated with ADAS. In this study, clinical data in a large consanguineous family with seven affected members were reviewed, and genomic DNA was extracted. For mutation screening, all exons of COL4A3 and COL4A4 genes were polymerase chain reaction-amplified and direct sequenced from genomic DNA, and the mutations were analyzed by comparing with members in this family, 100 ethnicitymatched controls and the sequence of COL4A3 and COL4A4 genes from GenBank. A novel mutation determining a nucleotide change was found, i.e. c.4195 A>T (p.Met1399Leu) at 44th exon of COL4A4 gene, and this mutation showed heterozygous in all patients of this family. Also a novel intron mutation (c.4127+11 C>T) was observed at COL4A4 gene. Thus the novel missense mutation c.4195 A>T (p.Met1399Leu) and the intron mutation (c.4127+11 C>T) at COL4A4 gene might be responsible for ADAS of this family. Our results broadened the spectrum of mutations in COL4A4 and had important implications in the diagnosis, prognosis, and genetic counselling of ADAS.
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Deltas C. Digenic inheritance and genetic modifiers. Clin Genet 2018; 93:429-438. [PMID: 28977688 DOI: 10.1111/cge.13150] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 09/27/2017] [Accepted: 09/28/2017] [Indexed: 12/28/2022]
Abstract
Digenic inheritance (DI) concerns pathologies with the simplest form of multigenic etiology, implicating more than 1 gene (and perhaps the environment). True DI is when biallelic or even triallelic mutations in 2 distinct genes, in cis or in trans, are necessary and sufficient to cause pathology with a defined diagnosis. In true DI, a heterozygous mutation in each of 2 genes alone is not associated with a recognizable phenotype. Well-documented diseases with true DI are so far rare and follow non-Mendelian inheritance. DI is also encountered when by serendipity, pathogenic mutations responsible for 2 distinct disease entities are co-inherited, leading to a mixed phenotype. Also, we can consider many true monogenic Mendelian conditions, which show impressively broad spectrum of phenotypes due to pseudo-DI, as a result of co-inheriting genetic modifiers (GMs). I am herewith reviewing examples of GM and embark on presenting some recent notable examples of true DI, with wider discussion of the literature. Undeniably, the advent of high throughput sequencing is bound to unravel more patients suffering with true DI conditions and elucidate many important GM, thus impacting precision medicine.
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Affiliation(s)
- C Deltas
- College of Medicine, Qatar University, Doha, Qatar.,Department of Biological Sciences, Molecular Medicine Research Center, University of Cyprus, Nicosia, Cyprus
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Papazachariou L, Papagregoriou G, Hadjipanagi D, Demosthenous P, Voskarides K, Koutsofti C, Stylianou K, Ioannou P, Xydakis D, Tzanakis I, Papadaki A, Kallivretakis N, Nikolakakis N, Perysinaki G, Gale DP, Diamantopoulos A, Goudas P, Goumenos D, Soloukides A, Boletis I, Melexopoulou C, Georgaki E, Frysira E, Komianou F, Grekas D, Paliouras C, Alivanis P, Vergoulas G, Pierides A, Daphnis E, Deltas C. Frequent COL4 mutations in familial microhematuria accompanied by later-onset Alport nephropathy due to focal segmental glomerulosclerosis. Clin Genet 2017. [PMID: 28632965 DOI: 10.1111/cge.13077] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Familial microscopic hematuria (FMH) is associated with a genetically heterogeneous group of conditions including the collagen-IV nephropathies, the heritable C3/CFHR5 nephropathy and the glomerulopathy with fibronectin deposits. The clinical course varies widely, ranging from isolated benign familial hematuria to end-stage renal disease (ESRD) later in life. We investigated 24 families using next generation sequencing (NGS) for 5 genes: COL4A3, COL4A4, COL4A5, CFHR5 and FN1. In 17 families (71%), we found 15 pathogenic mutations in COL4A3/A4/A5, 9 of them novel. In 5 families patients inherited classical AS with hemizygous X-linked COL4A5 mutations. Even more patients developed later-onset Alport-related nephropathy having inherited heterozygous COL4A3/A4 mutations that cause thin basement membranes. Amongst 62 heterozygous or hemizygous patients, 8 (13%) reached ESRD, while 25% of patients with heterozygous COL4A3/A4 mutations, aged >50-years, reached ESRD. In conclusion, COL4A mutations comprise a frequent cause of FMH. Heterozygous COL4A3/A4 mutations predispose to renal function impairment, supporting that thin basement membrane nephropathy is not always benign. The molecular diagnosis is essential for differentiating the X-linked from the autosomal recessive and dominant inheritance. Finally, NGS technology is established as the gold standard for the diagnosis of FMH and associated collagen-IV glomerulopathies, frequently averting the need for invasive renal biopsies.
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Affiliation(s)
- L Papazachariou
- Molecular Medicine Research Center & Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - G Papagregoriou
- Molecular Medicine Research Center & Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - D Hadjipanagi
- Molecular Medicine Research Center & Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - P Demosthenous
- Molecular Medicine Research Center & Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - K Voskarides
- Molecular Medicine Research Center & Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - C Koutsofti
- Molecular Medicine Research Center & Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - K Stylianou
- Department of Nephrology, University of Crete-Greece, Heraklion, Greece
| | - P Ioannou
- Department of Nephrology, University of Crete-Greece, Heraklion, Greece
| | - D Xydakis
- Department of Nephrology, University of Crete-Greece, Heraklion, Greece
| | - I Tzanakis
- Department of Nephrology, General Hospital of Chania, Crete, Greece
| | - A Papadaki
- Department of Nephrology, General Hospital of Chania, Crete, Greece
| | - N Kallivretakis
- Department of Nephrology, General Hospital of Chania, Crete, Greece
| | - N Nikolakakis
- Division of Nephrology, General Hospital of Rethymno, Crete, Greece
| | - G Perysinaki
- Division of Nephrology, General Hospital of Rethymno, Crete, Greece
| | - D P Gale
- UCL Division of Medicine and Centre for Nephrology, University College London, London, UK
| | | | - P Goudas
- IATOS Dialysis Unit, Patra, Greece
| | - D Goumenos
- Department of Nephrology, Medical School, University of Patras, Patra, Greece
| | - A Soloukides
- Protypo Nefrologiko Athinon Dialysis Center, Athens, Greece
| | - I Boletis
- Department of Nephrology, Laikon Hospital, Athens, Greece
| | - C Melexopoulou
- Department of Nephrology, Laikon Hospital, Athens, Greece
| | - E Georgaki
- Pediatric Nephrology Unit, "IASO" Children's Hospital, Athens, Greece
| | - E Frysira
- Department of Pediatrics, Athens University Medical School, Agia Sophia Children's Hospital, Athens, Greece
| | - F Komianou
- Department of Medical Genetics, Athens University Medical School, Agia Sophia Children's Hospital, Athens, Greece
| | - D Grekas
- University Hospital AXEPA, Thessaloniki, Greece
| | - C Paliouras
- Department of Nephrology, General Hospital of Rhodes, Rhodes, Greece
| | - P Alivanis
- Department of Nephrology, General Hospital of Rhodes, Rhodes, Greece
| | - G Vergoulas
- Organ Transplant Unit, Hippokratio General Hospital, Thessaloniki, Greece
| | - A Pierides
- Molecular Medicine Research Center & Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus.,Department of Nephrology, Hippocrateon Hospital, Nicosia, Cyprus
| | - E Daphnis
- Department of Nephrology, University of Crete-Greece, Heraklion, Greece
| | - C Deltas
- Molecular Medicine Research Center & Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
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Liu JH, Wei XX, Li A, Cui YX, Xia XY, Qin WS, Zhang MC, Gao EZ, Sun J, Gao CL, Liu FX, Wu QY, Li WW, Liu ZH, Li XJ. Novel mutations in COL4A3, COL4A4, and COL4A5 in Chinese patients with Alport Syndrome. PLoS One 2017; 12:e0177685. [PMID: 28542346 PMCID: PMC5436713 DOI: 10.1371/journal.pone.0177685] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 05/01/2017] [Indexed: 12/18/2022] Open
Abstract
Alport syndrome (AS) is a clinically and genetically heterogeneous, progressive nephropathy caused by mutations in COL4A3, COL4A4, and COL4A5, which encode type IV collagen. The large sizes of these genes and the absence of mutation hot spots have complicated mutational analysis by routine polymerase chain reaction (PCR)-based approaches. Here, in order to design a rapid and effective method for the genetic diagnosis of AS, we developed a strategy by utilizing targeted capture associated with next-generation sequencing (NGS) to analyze COL4A3, COL4A4, and COL4A5 simultaneously in 20 AS patients. All the coding exons and flanking sequences of COL4A3, COL4A4, and COL4A5 from the probands were captured followed by HiSeq 2500 sequencing. Candidate mutations were validated by classic Sanger sequencing and quantitative (q)PCR. Sixteen patients (16/20, 75%) showed X-linked inheritance, and four patients (4/20, 20%) showed autosomal recessive inheritance. None of the individuals had autosomal-dominant AS. Fifteen novel mutations, 6 known mutations, and 2 novel fragment deletions were detected by targeted capture and NGS. Of these novel mutations, 12, 3, and 2 mutations were detected in COL4A5, COL4A4, and COL4A3, respectively. A comparison of the clinical manifestations caused by different types of mutations in COL4A5 suggested that nonsense mutations and glycine substitution by an acidic amino acid are more severe than the other missense mutations. Pathogenic mutations were detected in 20 patients. These novel mutations can expand the genotypic spectrum of AS. Our results demonstrated that targeted capture and NGS technology are effective in the genetic diagnosis of AS.
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Affiliation(s)
- Jian-Hong Liu
- Institute of Clinical Laboratory Science, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Xiu-Xiu Wei
- Binhai Genomics Institute, BGI-Tianjin, BGI-shenzhen, Tianjin, China
| | - Ang Li
- Institute of Clinical Laboratory Science, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Ying-Xia Cui
- Institute of Clinical Laboratory Science, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Xin-Yi Xia
- Institute of Clinical Laboratory Science, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Wei-Song Qin
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Ming-Chao Zhang
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Er-Zhi Gao
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Jun Sun
- Binhai Genomics Institute, BGI-Tianjin, BGI-shenzhen, Tianjin, China
| | - Chun-Lin Gao
- Department of Pediatric Nephrology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Feng-Xia Liu
- Binhai Genomics Institute, BGI-Tianjin, BGI-shenzhen, Tianjin, China
| | - Qiu-Yue Wu
- Institute of Clinical Laboratory Science, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Wei-Wei Li
- Institute of Clinical Laboratory Science, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Zhi-Hong Liu
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
- * E-mail: (XJL); (A); (ZHL)
| | - Xiao-Jun Li
- Institute of Clinical Laboratory Science, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
- State Key Laboratory of Analytical Chemistry for Life Science, Department of Chemistry, Nanjing University, Nanjing, China
- * E-mail: (XJL); (A); (ZHL)
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A functional variant in NEPH3 gene confers high risk of renal failure in primary hematuric glomerulopathies. Evidence for predisposition to microalbuminuria in the general population. PLoS One 2017; 12:e0174274. [PMID: 28334007 PMCID: PMC5363870 DOI: 10.1371/journal.pone.0174274] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2016] [Accepted: 03/06/2017] [Indexed: 01/06/2023] Open
Abstract
Background Recent data emphasize that thin basement membrane nephropathy (TBMN) should not be viewed as a form of benign familial hematuria since chronic renal failure (CRF) and even end-stage renal disease (ESRD), is a possible development for a subset of patients on long-term follow-up, through the onset of focal and segmental glomerulosclerosis (FSGS). We hypothesize that genetic modifiers may explain this variability of symptoms. Methods We looked in silico for potentially deleterious functional SNPs, using very strict criteria, in all the genes significantly expressed in the slit diaphragm (SD). Two variants were genotyped in a cohort of well-studied adult TBMN patients from 19 Greek-Cypriot families, with a homogeneous genetic background. Patients were categorized as “Severe” or “Mild”, based on the presence or not of proteinuria, CRF and ESRD. A larger pooled cohort (HEMATURIA) of 524 patients, including IgA nephropathy patients, was used for verification. Additionally, three large general population cohorts [Framingham Heart Study (FHS), KORAF4 and SAPHIR] were used to investigate if the NEPH3-V353M variant has any renal effect in the general population. Results and conclusions Genotyping for two high-scored variants in 103 TBMN adult patients with founder mutations who were classified as mildly or severely affected, pointed to an association with variant NEPH3-V353M (filtrin). This promising result prompted testing in the larger pooled cohort (HEMATURIA), indicating an association of the 353M variant with disease severity under the dominant model (p = 3.0x10-3, OR = 6.64 adjusting for gender/age; allelic association: p = 4.2x10-3 adjusting for patients’ kinships). Subsequently, genotyping 6,531 subjects of the Framingham Heart Study (FHS) revealed an association of the homozygous 353M/M genotype with microalbuminuria (p = 1.0x10-3). Two further general population cohorts, KORAF4 and SAPHIR confirmed the association, and a meta-analysis of all three cohorts (11,258 individuals) was highly significant (p = 1.3x10-5, OR = 7.46). Functional studies showed that Neph3 homodimerization and Neph3-Nephrin heterodimerization are disturbed by variant 353M. Additionally, 353M was associated with differential activation of the unfolded protein response pathway, when overexpressed in stressed cultured undifferentiated podocyte cells, thus attesting to its functional significance. Genetics and functional studies support a “rare variant-strong effect” role for NEPH3-V353M, by exerting a negative modifier effect on primary glomerular hematuria. Additionally, genetics studies provide evidence for a role in predisposing homozygous subjects of the general population to micro-albuminuria.
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Prospective study on the potential of RAAS blockade to halt renal disease in Alport syndrome patients with heterozygous mutations. Pediatr Nephrol 2017; 32:131-137. [PMID: 27402170 DOI: 10.1007/s00467-016-3452-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 06/16/2016] [Accepted: 06/16/2016] [Indexed: 12/19/2022]
Abstract
BACKGROUND Patients with autosomal or X-linked Alport syndrome (AS) with heterozygous mutations in type IV collagen genes have a 1-20 % risk of progressing to end-stage renal disease during their lifetime. We evaluated the long-term renal outcome of patients at risk of progressive disease (chronic kidney disease stages 1-4) with/without nephroprotective therapy. METHODS This was a prospective, non-interventional, observational study which included data from a 4-year follow-up of AS patients with heterozygous mutations whose datasets had been included in an analysis of the 2010 database of the European Alport Registry. Using Kaplan-Meier estimates and logrank tests, we prospectively analyzed the updated datasets of 52 of these patients and 13 new datasets (patients added to the Registry after 2011). The effects of therapy, extrarenal symptoms and inheritance pattern on renal outcome were analyzed. RESULTS The mean prospective follow-up was 46 ± 10 months, and the mean time on therapy was 8.4 ± 4.4 (median 7; range 2-18) years. The time from the appearance of the first symptom to diagnosis was 8.1 ± 14.2 (range 0-52) years. At the time of starting therapy, 5.4 % of patients had an estimated glomerular filtration rate of <60 ml/min, 67.6 % had proteinuria and 27.0 % had microalbuminuria. Therapeutic strategies included angiotensin-converting enzymer inhibitors (97.1 %), angiotensin receptor antagonists (1 patient), dual therapy (11.8 %) and statins (8.8 %). Among patients included in the prospective dataset, prevented the need for dialysis. Among new patients, no patient at risk for renal failure progressed to the next disease stage after 4 years follow-up; three patients even regressed to a lower stage during therapy. CONCLUSIONS Treatment with blockers of the renin-angiotensin-aldosterone system prevents progressive renal failure in AS patients with heterozygous mutations in the genes causing AS. Considerable numbers of aging AS patients on dialysis may have heterozygous mutations in these genes (present in 1 % of total population) as underlying disease. Hence, greater alertness towards timely diagnosis and therapy has the potential to prevent progressive renal failure in most-if not all-AS patients with heterozygous mutations in the causal genes.
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Familial hematuria: A review. Medicina (B Aires) 2017; 53:1-10. [DOI: 10.1016/j.medici.2017.01.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 12/23/2016] [Accepted: 01/16/2017] [Indexed: 12/17/2022] Open
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Abstract
Finding better treatments for lupus nephritis requires an understanding of the pathogenesis of the causative systemic disease, how this leads to kidney disease, and how lupus nephritis progresses to end-stage kidney disease. Here, we provide a brief conceptual overview on the related pathomechanisms. As a main focus we discuss in detail the roles of neutrophils, dendritic cells, Toll-like receptors, and interferon-α in the pathogenesis of lupus nephritis by separately reviewing their roles in extrarenal systemic autoimmunity and in intrarenal inflammation and immunopathology.
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Kamiyoshi N, Nozu K, Fu XJ, Morisada N, Nozu Y, Ye MJ, Imafuku A, Miura K, Yamamura T, Minamikawa S, Shono A, Ninchoji T, Morioka I, Nakanishi K, Yoshikawa N, Kaito H, Iijima K. Genetic, Clinical, and Pathologic Backgrounds of Patients with Autosomal Dominant Alport Syndrome. Clin J Am Soc Nephrol 2016; 11:1441-1449. [PMID: 27281700 PMCID: PMC4974872 DOI: 10.2215/cjn.01000116] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 04/15/2016] [Indexed: 01/15/2023]
Abstract
BACKGROUND AND OBJECTIVES Alport syndrome comprises a group of inherited heterogeneous disorders involving CKD, hearing loss, and ocular abnormalities. Autosomal dominant Alport syndrome caused by heterozygous mutations in collagen 4A3 and/or collagen 4A4 accounts for <5% of patients. However, the clinical, genetic, and pathologic backgrounds of patients with autosomal dominant Alport syndrome remain unclear. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS We conducted a retrospective analysis of 25 patients with genetically proven autosomal dominant Alport syndrome and their family members (a total of 72 patients) from 16 unrelated families. Patients with suspected Alport syndrome after pathologic examination who were referred from anywhere in Japan for genetic analysis from 2006 to 2015 were included in this study. Clinical, laboratory, and pathologic data were collected from medical records at the point of registration for genetic diagnosis. Genetic analysis was performed by targeted resequencing of 27 podocyte-related genes, including Alport-related collagen genes, to make a diagnosis of autosomal dominant Alport syndrome and identify modifier genes or double mutations. Clinical data were obtained from medical records. RESULTS The median renal survival time was 70 years, and the median age at first detection of proteinuria was 17 years old. There was one patient with hearing loss and one patient with ocular lesion. Among 16 patients who underwent kidney biopsy, three showed FSGS, and seven showed thinning without lamellation of the glomerular basement membrane. Five of 13 detected mutations were reported to be causative mutations for autosomal recessive Alport syndrome in previous studies. Two families possessed double mutations in both collagen 4A3 and collagen 4A4, but no modifier genes were detected among the other podocyte-related genes. CONCLUSIONS The renal phenotype of autosomal dominant Alport syndrome was much milder than that of autosomal recessive Alport syndrome or X-linked Alport syndrome in men. It may, thus, be difficult to make an accurate diagnosis of autosomal dominant Alport syndrome on the basis of clinical or pathologic findings. No modifier genes were identified among the known podocyte-related genes.
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Affiliation(s)
- Naohiro Kamiyoshi
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Kandai Nozu
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Xue Jun Fu
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Naoya Morisada
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Yoshimi Nozu
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Ming Juan Ye
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Aya Imafuku
- Department of Nephrology, Toranomon Hospital, Tokyo, Japan
| | - Kenichiro Miura
- Department of Pediatrics, The University of Tokyo, Tokyo, Japan; and
| | - Tomohiko Yamamura
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Shogo Minamikawa
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Akemi Shono
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Takeshi Ninchoji
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Ichiro Morioka
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Koichi Nakanishi
- Department of Pediatrics, Wakayama Medical University, Wakayama, Japan
| | | | - Hiroshi Kaito
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Kazumoto Iijima
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
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40
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Savva I, Pierides A, Deltas C. RAAS inhibition and the course of Alport syndrome. Pharmacol Res 2016; 107:205-210. [PMID: 26995302 DOI: 10.1016/j.phrs.2016.03.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 03/04/2016] [Accepted: 03/14/2016] [Indexed: 12/26/2022]
Abstract
Alport syndrome (AS) is a hereditary progressive glomerulonephritis with a high life-time risk for end-stage renal disease (ESRD). Most patients will reach ESRD before the age of 30 years, while a subset of them with milder mutations will do so at older ages, even after 50 years. Frequent extrarenal manifestations are hearing loss and ocular abnormalities. AS is a genetically heterogeneous collagen IV nephropathy, with 85% of the cases caused by mutations in the X-linked COL4A5 gene and the rest by homozygous or compound heterozygous mutations in either the COL4A3 or the COL4A4 gene on chromosome 2q36-37. There is no radical cure for the disease and attempts to use various stem cell therapies in animal models have been met with ambiguous success. However, effective treatment has been accomplished with pharmacological intervention at the renin-angiotensin-aldosterone system (RAAS), first in animal models of AS and more recently in humans. Angiotensin converting enzyme inhibitors (ACEis) and angiotensin receptor blockers (ARBs) have been shown to significantly delay the progression of chronic kidney disease and the onset of ESRD. Also, renin inhibitors and aldosterone blockade were used with positive results, while the combination of ACEis and ARBs was met with mixed success. An important study, the EARLY-PROTECT, aims at evaluating the efficacy of ACEis when administered very early on in children with AS. Novel therapies are also tested experimentally or are under design in animal models by several groups, including the use of amniotic fluid stem cells and synthetic chaperones.
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Affiliation(s)
- Isavella Savva
- Molecular Medicine Research Center and Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Cyprus
| | - Alkis Pierides
- Molecular Medicine Research Center and Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Cyprus; Department of Nephrology, Hippocrateon Hospital, Nicosia, Cyprus
| | - Constantinos Deltas
- Molecular Medicine Research Center and Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Cyprus.
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Kovács G, Kalmár T, Endreffy E, Ondrik Z, Iványi B, Rikker C, Haszon I, Túri S, Sinkó M, Bereczki C, Maróti Z. Efficient Targeted Next Generation Sequencing-Based Workflow for Differential Diagnosis of Alport-Related Disorders. PLoS One 2016; 11:e0149241. [PMID: 26934356 PMCID: PMC4775026 DOI: 10.1371/journal.pone.0149241] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2015] [Accepted: 01/28/2016] [Indexed: 01/02/2023] Open
Abstract
Alport syndrome (AS) is an inherited type IV collagen nephropathies characterized by microscopic hematuria during early childhood, the development of proteinuria and progression to end-stage renal disease. Since choosing the right therapy, even before the onset of proteinuria, can delay the onset of end-stage renal failure and improve life expectancy, the earliest possible differential diagnosis is desired. Practically, this means the identification of mutation(s) in COL4A3-A4-A5 genes. We used an efficient, next generation sequencing based workflow for simultaneous analysis of all three COL4A genes in three individuals and fourteen families involved by AS or showing different level of Alport-related symptoms. We successfully identified mutations in all investigated cases, including 14 unpublished mutations in our Hungarian cohort. We present an easy to use unified clinical/diagnostic terminology and workflow not only for X-linked but for autosomal AS, but also for Alport-related diseases. In families where a diagnosis has been established by molecular genetic analysis, the renal biopsy may be rendered unnecessary.
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Affiliation(s)
- Gábor Kovács
- University of Szeged, Faculty of Medicine, Department of Pediatrics and Pediatric Health Center, Szeged, Hungary
| | - Tibor Kalmár
- University of Szeged, Faculty of Medicine, Department of Pediatrics and Pediatric Health Center, Szeged, Hungary
| | - Emőke Endreffy
- University of Szeged, Faculty of Medicine, Department of Pediatrics and Pediatric Health Center, Szeged, Hungary
| | - Zoltán Ondrik
- University of Szeged, Faculty of Medicine, First Department of Internal Medicine, Szeged, Hungary
| | - Béla Iványi
- University of Szeged, Faculty of Medicine, Department of Pathology, Szeged, Hungary
| | - Csaba Rikker
- Péterfy Sándor Hospital Department of Internal Medicine 1, Budapest, Hungary
| | - Ibolya Haszon
- University of Szeged, Faculty of Medicine, Department of Pediatrics and Pediatric Health Center, Szeged, Hungary
| | - Sándor Túri
- University of Szeged, Faculty of Medicine, Department of Pediatrics and Pediatric Health Center, Szeged, Hungary
| | - Mária Sinkó
- University of Szeged, Faculty of Medicine, Department of Pediatrics and Pediatric Health Center, Szeged, Hungary
| | - Csaba Bereczki
- University of Szeged, Faculty of Medicine, Department of Pediatrics and Pediatric Health Center, Szeged, Hungary
| | - Zoltán Maróti
- University of Szeged, Faculty of Medicine, Department of Pediatrics and Pediatric Health Center, Szeged, Hungary
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COL4A3/COL4A4 heterozygous mutations with TBMN presenting as focal segmental glomerulosclerosis. Kidney Int 2015; 87:859. [PMID: 25826548 DOI: 10.1038/ki.2015.38] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Anders HJ, Weidenbusch M, Rovin B. Unmet medical needs in lupus nephritis: solutions through evidence-based, personalized medicine. Clin Kidney J 2015; 8:492-502. [PMID: 26413272 PMCID: PMC4581390 DOI: 10.1093/ckj/sfv072] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 07/17/2015] [Indexed: 12/12/2022] Open
Abstract
Lupus nephritis (LN) remains a kidney disease with significant unmet medical needs despite extensive clinical and translational research over the past decade. These include the need to (i) predict the individual risk for LN in a patient with systemic lupus erythematosus, (ii) identify the best therapeutic option for an individual patient, (iii) distinguish chronic kidney damage from active immunologic kidney injury, (iv) develop efficient treatments with acceptable or no side effects and improve the design of randomized clinical trials so that effective drugs demonstrate efficacy. This review discusses the underlying reasons for these unmet medical needs and options of how to overcome them in the future.
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Affiliation(s)
- Hans-Joachim Anders
- Medizinische Klinik and Poliklinik IV, Klinikum der Universität München, Munich, Germany
| | - Marc Weidenbusch
- Medizinische Klinik and Poliklinik IV, Klinikum der Universität München, Munich, Germany
| | - Brad Rovin
- Division of Nephrology, Ohio State University Wexner Medical Center, Columbus, OH, USA
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Deltas C, Savva I, Voskarides K, Papazachariou L, Pierides A. Carriers of Autosomal Recessive Alport Syndrome with Thin Basement Membrane Nephropathy Presenting as Focal Segmental Glomerulosclerosis in Later Life. Nephron Clin Pract 2015. [PMID: 26201269 DOI: 10.1159/000435789] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Collagen IV nephropathies (COL4Ns) comprise benign familial microscopic hematuria, thin basement membrane nephropathy (TBMN), X-linked Alport syndrome (AS) and also autosomal recessive and dominant AS. Apart from the X-linked form of AS, which is caused by hemizygous mutations in the COL4A5 gene, the other entities are caused by mutations in the COL4A3 or COL4A4 genes. The diagnosis of these conditions used to be based on clinical and/or histological findings of renal biopsies, but it is the new molecular genetics approach that revolutionised their investigation and proved particularly instrumental, especially, in many not so clear-cut cases. More recently, the spectrum of COL4N has expanded to include late onset focal segmental glomerulosclerosis (FSGS) that develops on top of TBMN in later life. Also, other reports showed that some patients with a primary diagnosis of familial FSGS proved to have variants in COL4 genes. In the presence of a renal biopsy picture of FSGS and in the absence of either electron microscopy studies or molecular genetic studies that point to TBMN and COL4N, the patient and his family may be mistakenly diagnosed with hereditary FSGS leading to unnecessary further investigations, erroneous family counselling and improper corticosteroid treatment. TBMN is a frequent finding in the general population, and according to several recent reports, it may be the underlying cause and the explanation for many familial and sporadic cases of late-onset FSGS with non-nephrotic proteinuria. This is an important new finding that needs widespread recognition. It is anticipated that the molecular genetic analysis with next generation sequencing will certainly offer timely correct diagnosis.
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Affiliation(s)
- Constantinos Deltas
- Molecular Medicine Research Center and Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
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Wiggs JL. Glaucoma Genes and Mechanisms. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 134:315-42. [PMID: 26310163 DOI: 10.1016/bs.pmbts.2015.04.008] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Genetic studies have yielded important genes contributing to both early-onset and adult-onset forms of glaucoma. The proteins encoded by the current collection of glaucoma genes participate in a broad range of cellular processes and biological systems. Approximately half the glaucoma-related genes function in the extracellular matrix, however proteins involved in cytokine signaling, lipid metabolism, membrane biology, regulation of cell division, autophagy, and ocular development also contribute to the disease pathogenesis. While the function of these proteins in health and disease are not completely understood, recent studies are providing insight into underlying disease mechanisms, a critical step toward the development of gene-based therapies. In this review, genes known to cause early-onset glaucoma or contribute to adult-onset glaucoma are organized according to the cell processes or biological systems that are impacted by the function of the disease-related protein product.
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Affiliation(s)
- Janey L Wiggs
- Harvard Medical School, and Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA.
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The Author Replies:. Kidney Int 2015; 87:859-60. [PMID: 25826549 PMCID: PMC4654678 DOI: 10.1038/ki.2015.39] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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