BACKGROUND Alport syndrome(AS)is an inherited disease of the glomerular basement membrane caused by mutations in genes encodingα3,α4,orα5 chains of type IV collagen.It manifests with hematuria or proteinuria,which ...BACKGROUND Alport syndrome(AS)is an inherited disease of the glomerular basement membrane caused by mutations in genes encodingα3,α4,orα5 chains of type IV collagen.It manifests with hematuria or proteinuria,which is often accompanied by hearing impairments and ocular abnormalities.Histopathologically,AS shows mesangial proliferation and sometimes incidental immunoglobulin A(IgA)deposition.Hematuria or proteinuria is also a common presentation in patients with IgA nephropathy that makes it difficult to differentially diagnose AS and IgA nephropathy solely based on these clinical and pathological features.CASE SUMMARY Herein,we present the case of a 59-year-old female patient who was admitted to our hospital with persistent microscopic hematuria and occasional proteinuria that had lasted for>2 years.This patient had a familial history of renal disease and was diagnosed with autosomal dominant AS(ADAS)and IgA nephropathy based on the findings of renal biopsy as well as genetic testing performed using whole-exome sequencing,which suggested that the patient carried a novel heterozygous variation(c.888G>A:p.Gln296Gln)in the COL4A3 gene that enriches the mutation spectrum of ADAS.The proband received an angiotensin receptor blocker therapy after a definitive diagnosis was established.After one year of therapy,a significant reduction in proteinuria was observed.The number of microscopic red blood cells per high-power field decreased to one-quarter of the baseline levels.Renal function also maintained well during the follow-up.CONCLUSION Our case highlights the significance of performing kidney biopsy and genetic testing in the diagnosis of AS and familial IgA nephropathy.展开更多
Focal segmental glomerulosclerosis （FSGS） is a histologically identifiable gtomerular injury often leading to proteinuria and renal failure. To identify its causal genes, whole-exome sequencing and Sanger sequencing...Focal segmental glomerulosclerosis （FSGS） is a histologically identifiable gtomerular injury often leading to proteinuria and renal failure. To identify its causal genes, whole-exome sequencing and Sanger sequencing were performed on a large Chinese cohort that comprised 40 FSGS families, 50 sporadic FSGS patients, 9 independent autosomal recessive Atport＇s syndrome （ARAS） patients, and 190 ethnically matched healthy controls. Patients with extrarenal manifestations, indicating systemic diseases or other known hereditary renal diseases, were excluded. Heterozygous COL4A3 mutations were identified in five （12.5%） FSGS families and one （2%） sporadic FSGS patient. All identified mutations disrupted highly conserved protein sequences and none of them was found in either public databases or the 190 healthy controls. Of the FSGS patients with heterozygous COL4A3 mutations, segmental thinning of the glomerular base membrane （GBM） was only detected in the patient with electronic microscopy examination results available. Five ARAS patients （55.6%） had homozygous or compound-heterozygous mutations in COL4.43 or COL4A4. Serious changes in the G BM, hearing loss, and ocular abnormalities were found in 100%, 80%, and 40% of the ARAS patients, respectively. Overall, a new sub- group of FSGS patients resulting from heterozygous C01.4A3 mutations was identified. The mutations are relatively frequent in famiUes diagnosed with inherited forms of FSGS. Thus, we suggest screening for C01.4A3 mutations in familial FSGS patients.展开更多
Background:Collagen typeⅣ(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 mut...Background:Collagen typeⅣ(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/Casg)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 MG 132 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 typeⅣ-related nephropathy caused by a severely truncated COL4A3 mutation.展开更多
目的分析一个Alport综合征家庭的临床特征及遗传学病因。方法选取2019年12月于南通大学附属医院耳鼻咽喉科门诊就诊的一个AS耳聋家庭(NT103),该家庭家系成员包括父母姐妹4例,其中姐姐为AS患者(Ⅱ-1),其余人临床表现均无异常。对Alport...目的分析一个Alport综合征家庭的临床特征及遗传学病因。方法选取2019年12月于南通大学附属医院耳鼻咽喉科门诊就诊的一个AS耳聋家庭(NT103),该家庭家系成员包括父母姐妹4例,其中姐姐为AS患者(Ⅱ-1),其余人临床表现均无异常。对Alport综合征家庭进行详尽临床资料的收集和评估;采用基于家庭为单位,结合定向捕获技术二代测序的策略分析测序结果;对可疑致病基因的变异位点进行家庭内Sanger测序验证,依据美国医学遗传学与基因组学学会(American College of Medical Genetics and Genomics,ACMG)指南确定变异致病性。结果该Alport综合征家庭的先证者表现为持续性血尿伴感音神经性聋但无眼部异常。定向捕获及Sanger测序显示,患者(Ⅱ-1)携带COL4A3复合杂合错义突变,c.4793T>G,p.L1598R/c.4981C>T,p.R1661C分别来自父母双亲,且在家系其他成员中共分离。根据ACMG指南,该Alport综合征家庭先证者携带的COL4A3基因复合杂合突变位点,判定为疑似致病变异。结论本研究丰富了COL4A3临床表型谱及基因突变谱。此外,对于疑似Alport综合征的患者,提倡常规开展基因检测以实现Alport综合征患者的早期个体化精准诊治。展开更多
基金Supported by The Major Project of Zhejiang Administration of Traditional Chinese Medicine,No.2020ZZ008.
文摘BACKGROUND Alport syndrome(AS)is an inherited disease of the glomerular basement membrane caused by mutations in genes encodingα3,α4,orα5 chains of type IV collagen.It manifests with hematuria or proteinuria,which is often accompanied by hearing impairments and ocular abnormalities.Histopathologically,AS shows mesangial proliferation and sometimes incidental immunoglobulin A(IgA)deposition.Hematuria or proteinuria is also a common presentation in patients with IgA nephropathy that makes it difficult to differentially diagnose AS and IgA nephropathy solely based on these clinical and pathological features.CASE SUMMARY Herein,we present the case of a 59-year-old female patient who was admitted to our hospital with persistent microscopic hematuria and occasional proteinuria that had lasted for>2 years.This patient had a familial history of renal disease and was diagnosed with autosomal dominant AS(ADAS)and IgA nephropathy based on the findings of renal biopsy as well as genetic testing performed using whole-exome sequencing,which suggested that the patient carried a novel heterozygous variation(c.888G>A:p.Gln296Gln)in the COL4A3 gene that enriches the mutation spectrum of ADAS.The proband received an angiotensin receptor blocker therapy after a definitive diagnosis was established.After one year of therapy,a significant reduction in proteinuria was observed.The number of microscopic red blood cells per high-power field decreased to one-quarter of the baseline levels.Renal function also maintained well during the follow-up.CONCLUSION Our case highlights the significance of performing kidney biopsy and genetic testing in the diagnosis of AS and familial IgA nephropathy.
基金This workwas supported by grants from the National Basic Research Program of China 973, grant no. 2012CB517600 （no. 2012CB517604）, the National Natural Science Foundation of China （no. 81030015, 81070568, 81370015, and 81000295）, the International Cooperation and Exchange Projects of Shanghai Science and Technology Committee （no. 14430721000）, and the Chinese Medical Association Clinical Research Special Fund （no. 13030280413）.
文摘Focal segmental glomerulosclerosis （FSGS） is a histologically identifiable gtomerular injury often leading to proteinuria and renal failure. To identify its causal genes, whole-exome sequencing and Sanger sequencing were performed on a large Chinese cohort that comprised 40 FSGS families, 50 sporadic FSGS patients, 9 independent autosomal recessive Atport＇s syndrome （ARAS） patients, and 190 ethnically matched healthy controls. Patients with extrarenal manifestations, indicating systemic diseases or other known hereditary renal diseases, were excluded. Heterozygous COL4A3 mutations were identified in five （12.5%） FSGS families and one （2%） sporadic FSGS patient. All identified mutations disrupted highly conserved protein sequences and none of them was found in either public databases or the 190 healthy controls. Of the FSGS patients with heterozygous COL4A3 mutations, segmental thinning of the glomerular base membrane （GBM） was only detected in the patient with electronic microscopy examination results available. Five ARAS patients （55.6%） had homozygous or compound-heterozygous mutations in COL4.43 or COL4A4. Serious changes in the G BM, hearing loss, and ocular abnormalities were found in 100%, 80%, and 40% of the ARAS patients, respectively. Overall, a new sub- group of FSGS patients resulting from heterozygous C01.4A3 mutations was identified. The mutations are relatively frequent in famiUes diagnosed with inherited forms of FSGS. Thus, we suggest screening for C01.4A3 mutations in familial FSGS patients.
基金grants from the National Key Research and Development Program of China(No.2016YFC0904100)National Natural Science Foundation of China(Nos.81870460,81570598,and 81370015)+3 种基金Science and Technology Innovation Action Plan of Shanghai Science and Technology Committee(No.17441902200)Shanghai Municipal Education Commission,Gaofeng Clinical Medicine Grant(No.20152207)Shanghai Jiao Tong University School of Medicine,MultiCenter Clinical Research Project(No.DLY201510)the Shanghai Health and Family Planning Committee Hundred Talents Program(No.2018BR37).
文摘Background:Collagen typeⅣ(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/Casg)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 MG 132 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 typeⅣ-related nephropathy caused by a severely truncated COL4A3 mutation.
文摘目的分析一个Alport综合征家庭的临床特征及遗传学病因。方法选取2019年12月于南通大学附属医院耳鼻咽喉科门诊就诊的一个AS耳聋家庭(NT103),该家庭家系成员包括父母姐妹4例,其中姐姐为AS患者(Ⅱ-1),其余人临床表现均无异常。对Alport综合征家庭进行详尽临床资料的收集和评估;采用基于家庭为单位,结合定向捕获技术二代测序的策略分析测序结果;对可疑致病基因的变异位点进行家庭内Sanger测序验证,依据美国医学遗传学与基因组学学会(American College of Medical Genetics and Genomics,ACMG)指南确定变异致病性。结果该Alport综合征家庭的先证者表现为持续性血尿伴感音神经性聋但无眼部异常。定向捕获及Sanger测序显示,患者(Ⅱ-1)携带COL4A3复合杂合错义突变,c.4793T>G,p.L1598R/c.4981C>T,p.R1661C分别来自父母双亲,且在家系其他成员中共分离。根据ACMG指南,该Alport综合征家庭先证者携带的COL4A3基因复合杂合突变位点,判定为疑似致病变异。结论本研究丰富了COL4A3临床表型谱及基因突变谱。此外,对于疑似Alport综合征的患者,提倡常规开展基因检测以实现Alport综合征患者的早期个体化精准诊治。
