Background：Charcot-Marie-Tooth disease （CMT） is the most common inherited peripheral neuropathy.A great number of causative genes have been described in CMT,and among them,the heterozygous duplication of peripheral...Background：Charcot-Marie-Tooth disease （CMT） is the most common inherited peripheral neuropathy.A great number of causative genes have been described in CMT,and among them,the heterozygous duplication of peripheral myelin protein-22 （PMP22） is the major cause.Although the missense mutation in PMP22 is rarely reported,it has been demonstrated to be associated with CMT.This study described a novel missense mutation of PMP22 in a Chinese family with CMT phenotype.Methods：Targeted next-generation sequencing （NGS） was used to screen the causative genes in a family featured with an autosomal dominant demyelinating form of CMT.The potential variants identified by targeted NGS were verified by Sanger sequencing and classified according to the American College of Medical Genetics and Genomics standards and guidelines.Further cell transfection studies were performed to characterize the function of the novel variant.Results：Using targeted NGS,a novel heterozygous missense variant in PMP22 （c.320G〉A,p.G107D） was identified.In vitro cell functional studies revealed that mutant PMP22 protein carrying p.G 107D mutation lost the ability to reach the plasma membrane,was mainly retained in the endoplasmic reticulum,and induced cell apoptosis.Conclusions：This study supported the notion that missense mutations in PMP22 give rise to a CMT phenotype,possibly through a toxic gain-of-function mechanism.展开更多
Genetic factors may be learnt from families with gene mutations that render nerve-injury sus- ceptibility even to ordinary physical activities. A typical example is hereditary neuropathy with liability to pressure pal...Genetic factors may be learnt from families with gene mutations that render nerve-injury sus- ceptibility even to ordinary physical activities. A typical example is hereditary neuropathy with liability to pressure palsies （HNPP）. HNPP is caused by a heterozygous deletion of PMP22 gene. PMP22 deficiency disrupts myelin junctions （such as tight junction and adherens junctions）, leading to abnormally increased myelin permeability that explains the nerve susceptibility to injury. This finding should motivate investigators to identify additional genetic factors contribut- ing to nerve vulnerability of injury.展开更多
为提高患者自身、家属及临床工作者对人类周围髓鞘蛋白22基因(peripheral myelin protein-22,PMP22)及其导致的遗传性压力易感性周围神经病(hereditary neuropathy with liability to pressure palsies,HNPP)的认知和诊断水平,该文对PM...为提高患者自身、家属及临床工作者对人类周围髓鞘蛋白22基因(peripheral myelin protein-22,PMP22)及其导致的遗传性压力易感性周围神经病(hereditary neuropathy with liability to pressure palsies,HNPP)的认知和诊断水平,该文对PMP22基因及其导致的主要神经病进行了论述,并着重论述了遗传性压力易感性周围神经病(HNPP)的临床表现、神经电生理学检查结果、神经病理学及其发病机制等方面。在此基础上,对HNPP患者的预防和治疗提出了一些建议供参考。展开更多
目的:遗传性压力易感性周围神经病(hereditary neuropathy with liability to pressure palsy,HNPP)是一种少见的常染色体显性遗传周围神经病,通常由周围髓鞘蛋白22(peripheral myelin protein 22,PMP22)基因杂合缺失突变引起。本研究...目的:遗传性压力易感性周围神经病(hereditary neuropathy with liability to pressure palsy,HNPP)是一种少见的常染色体显性遗传周围神经病,通常由周围髓鞘蛋白22(peripheral myelin protein 22,PMP22)基因杂合缺失突变引起。本研究旨在探讨HNPP患者的临床和分子遗传学特征。方法:纳入2009至2023年就诊于中南大学湘雅三医院神经内科的HNPP患者,收集并分析患者的一般临床资料、神经电生理和分子遗传学检查结果。分子遗传学检查为提取外周血基因组DNA后采用多重连接探针扩增技术(multiplex ligation-dependent probe amplification,MLPA)进行PMP22大片段缺失的筛查;若未检测到PMP22缺失突变,则用二代测序法筛查PMP22点突变。进一步对HNPP相关文献进行回顾,分析HNPP患者的临床和分子遗传学特征。结果:共纳入来自24个无血缘关系的中国汉族家系的34例HNPP患者,包括25名男性和9名女性,平均22.0岁起病,有阳性家族史的家系占62.5%。30例患者出现周围神经麻痹的症状,常表现为发作性单肢无力伴/或麻木(25/30),亦可表现为发作性单侧喉返神经(迷走神经)麻痹(2/30)。体格检查可发现受累神经相应支配区域的肌肉无力(23/29)和浅感觉减退(9/29),踝反射减弱或消失(20/29),肢体远端肌肉萎缩(8/29)及高弓足(5/29)。多数患者(26/30)在急性发作后可完全恢复正常。有31例患者完成神经电生理检查,均表现为多发性周围神经损害,以运动及感觉神经髓鞘损害为主,多数患者可有远端运动潜伏期(distal motor latency,DML)明显延长,轻至中度的神经传导速度减慢,复合肌肉动作电位(compound muscle action potential,CMAP)及感觉神经动作电位(sensory nerve action potential,SNAP)波幅降低,有时可出现传导阻滞。正中神经运动传导速度为(48.5±5.5)m/s,CMAP波幅为(8.4±5.1)mV;正中神经感觉传导速度为(37.4±10.5)m/s,SNAP波幅为(14.4±13.0)μV。在24个HNPP家系中,经MLPA检测证实有23个家系为PMP22杂合缺失突变导致,经二代测序证实剩余1个家系为PMP22 c.434delT突变所致。文献检索到1734个进行了基因检测的HNPP确诊家系,其基因检测结果再次证实了PMP22杂合缺失突变是最常见的突变类型,占93.4%,其余突变类型包括PMP22微小突变(4.0%)、PMP22杂合不完全缺失突变(0.6%)、PMP22复杂易位突变(0.1%)。目前HNPP相关的PMP22微小突变共报道38种,包括错义突变(10/38)、无义突变(4/38)、碱基缺失突变(13/38)、碱基插入突变(3/38)、剪切位点突变(8/38)。HNPP患者最常表现为发作性无痛性单神经麻痹,腓总神经、尺神经和臂丛神经受累最为常见,约占75%。颅神经受累的患者仅有18例报道。结论:PMP22杂合缺失突变是HNPP最常见的突变类型。HNPP以发作性无痛性单神经麻痹为主要特点,主要累及腓总神经、尺神经等周围神经。神经电生理检查对于诊断本病具有较高的灵敏度和特异度,表现为广泛的脱髓鞘改变。对于怀疑HNPP的患者,首选完善神经电生理检查及PMP22大片段杂合缺失的检测。必要时可以完善Sanger测序或二代测序,对PMP22其他突变类型进行检测以防漏诊。展开更多
遗传性压力易感性周围神经病(hereditary neuropathy with liability to pressure palsies,HNPP)是一种染色体17p11.2的杂合性缺失所致的常染色体显性遗传性疾病,多散发存在,以易受压部位周围神经损害为主要临床表现,临床症状多样,常易...遗传性压力易感性周围神经病(hereditary neuropathy with liability to pressure palsies,HNPP)是一种染色体17p11.2的杂合性缺失所致的常染色体显性遗传性疾病,多散发存在,以易受压部位周围神经损害为主要临床表现,临床症状多样,常易漏诊,基因检测可明确诊断。本文将从3个临床病例,结合既往文献报道对HNPP进行讨论。展开更多
3-O-beta-D-xylopyranosyl-6-O-beta-D-glucopyranosyl-cycloastragenol （astragaloside IV）, the main active component of the traditional Chinese medicine astragalus membranaceus, has been shown to be neuroprotective. Thi...3-O-beta-D-xylopyranosyl-6-O-beta-D-glucopyranosyl-cycloastragenol （astragaloside IV）, the main active component of the traditional Chinese medicine astragalus membranaceus, has been shown to be neuroprotective. This study investigated whether astragaloside IV could promote the repair of injured sciatic nerve. Denervated sciatic nerve of mice was subjected to anastomosis. The mice were intraperitoneally injected with 10, 5, 2.5 mg/kg astragaloside IV per day for 8 consecutive days Western blot assay and real-time PCR results demonstrated that growth-associated protein-43 ex- pression was upregulated in mouse spinal cord segments L4-6 after intervention with 10, 5, 2.5 mg/kg astragaloside IV per day in a dose-dependent manner. Luxol fast blue staining and elec- trophysiological detection suggested that astragaloside IV elevated the number and diameter of myelinated nerve fibers, and simultaneously increased motor nerve conduction velocity and action potential amplitude in the sciatic nerve of mice. These results indicated that astragaloside IV con- tributed to sciatic nerve regeneration and functional recovery in mice. The mechanism underlying this effect may be associated with the upregulation of growth-associated protein-43 expression.展开更多
We used the allele-specific PCR-double digestion method on peripheral myelin protein 22 （PMP22） to determine duplication and deletion mutations in the proband and family members of one family with Charcot-Marie-Toot...We used the allele-specific PCR-double digestion method on peripheral myelin protein 22 （PMP22） to determine duplication and deletion mutations in the proband and family members of one family with Charcot-Marie-Tooth disease type 1 and one family with hereditary neuropathy with liability to pressure palsies. The proband and one subclinical family member from the Charcot-Marie-Tooth disease type 1 family had a PMP22 gene duplication; one patient from the hereditary neuropathy with liability to pressure palsies family had a PMP22 gene deletion. Electron microscopic analysis of ultrathin sections of the superficial peroneal nerve from the two probands demonstrated demyelination and myelin sheath hyperplasia, as well as an ＇onion-like＇ structure in the Charcot-Marie-Tooth disease type 1A patient. We observed an irregular thickened myelin sheath and ＇mouse-nibbled＇-Iike changes in the patient with hereditary neuropathy with liability to pressure palsies. In the Charcot-Marie-Tooth disease type 1A patient, nerve electrophysiological examination revealed moderate-to-severe reductions in the motor and sensory conduction velocities of the bilateral median nerve, ulnar nerve, tibial nerve, and sural nerve. Moreover, the compound muscle action potential amplitude was decreased. In the patient with hereditary neuropathy with liability to pressure palsies, the nerve conduction velocity of the bilateral tibial nerve and sural nerve was moderately reduced, and the nerve conduction velocity of the median nerve and ulnar nerve of both upper extremities was slightly reduced.展开更多
目的探讨遗传性压力易感性周围神经病（hereditary neuropathy with liability to pressurepalsies，HNPP）的临床、神经电生理及基因特点，为该病的诊断提供依据。方法对1个家系的4例患者进行临床特点总结，行电生理检查和基因检测。结...目的探讨遗传性压力易感性周围神经病（hereditary neuropathy with liability to pressurepalsies，HNPP）的临床、神经电生理及基因特点，为该病的诊断提供依据。方法对1个家系的4例患者进行临床特点总结，行电生理检查和基因检测。结果4例患者均表现为反复发作的周围神经受到轻微牵拉或压迫后出现运动感觉障碍，电生理检查示广泛性多发性的周围神经潜伏期延长，传导速度减慢，易卡压部位出现传导阻滞。基因检测示PMP22基因缺失突变。结论HNPP多以神经易卡压部位发病，表现为受累神经支配区的运动感觉异常，神经电生理表现为广泛神经脱髓鞘损伤，基因检测能确诊。展开更多
基金This study was supported by the grants from the National Natural Science Foundation of China （No. 81125009）, and the research foundation for distinguished scholar of Zhejiang University （No. 188020-193810101/089）.
文摘Background：Charcot-Marie-Tooth disease （CMT） is the most common inherited peripheral neuropathy.A great number of causative genes have been described in CMT,and among them,the heterozygous duplication of peripheral myelin protein-22 （PMP22） is the major cause.Although the missense mutation in PMP22 is rarely reported,it has been demonstrated to be associated with CMT.This study described a novel missense mutation of PMP22 in a Chinese family with CMT phenotype.Methods：Targeted next-generation sequencing （NGS） was used to screen the causative genes in a family featured with an autosomal dominant demyelinating form of CMT.The potential variants identified by targeted NGS were verified by Sanger sequencing and classified according to the American College of Medical Genetics and Genomics standards and guidelines.Further cell transfection studies were performed to characterize the function of the novel variant.Results：Using targeted NGS,a novel heterozygous missense variant in PMP22 （c.320G〉A,p.G107D） was identified.In vitro cell functional studies revealed that mutant PMP22 protein carrying p.G 107D mutation lost the ability to reach the plasma membrane,was mainly retained in the endoplasmic reticulum,and induced cell apoptosis.Conclusions：This study supported the notion that missense mutations in PMP22 give rise to a CMT phenotype,possibly through a toxic gain-of-function mechanism.
基金supported by grants from NINDS R01NS066927Department of Veterans Affairs R&D funds
文摘Genetic factors may be learnt from families with gene mutations that render nerve-injury sus- ceptibility even to ordinary physical activities. A typical example is hereditary neuropathy with liability to pressure palsies （HNPP）. HNPP is caused by a heterozygous deletion of PMP22 gene. PMP22 deficiency disrupts myelin junctions （such as tight junction and adherens junctions）, leading to abnormally increased myelin permeability that explains the nerve susceptibility to injury. This finding should motivate investigators to identify additional genetic factors contribut- ing to nerve vulnerability of injury.
文摘周围髓鞘蛋白22基因(peripheral myelin protein-22,PMP22)相关性周围神经病是一组以PMP22基因突变导致的遗传性周围神经病,不同的突变类型是导致不同的临床表型的关键,大致可以分为五类:PMP22片段重复突变导致腓骨肌萎缩症1A型(Charcot-Marie-Tooth type-1A,CMT1A),PMP22缺失突变所致遗传性压迫易感性神经病(hereditary neuropathy with liability to pressure palsies,HNPP),PMP22基因点突变可引起CMT1E以及Dejerine-Sottas综合征(DSS)、Roussy-Levy综合征(RLS)等。本文就PMP22基因相关性周围神经病的临床及遗传学特点做一综述。
文摘为提高患者自身、家属及临床工作者对人类周围髓鞘蛋白22基因(peripheral myelin protein-22,PMP22)及其导致的遗传性压力易感性周围神经病(hereditary neuropathy with liability to pressure palsies,HNPP)的认知和诊断水平,该文对PMP22基因及其导致的主要神经病进行了论述,并着重论述了遗传性压力易感性周围神经病(HNPP)的临床表现、神经电生理学检查结果、神经病理学及其发病机制等方面。在此基础上,对HNPP患者的预防和治疗提出了一些建议供参考。
文摘遗传性压力易感性周围神经病(hereditary neuropathy with liability to pressure palsies,HNPP)是一种染色体17p11.2的杂合性缺失所致的常染色体显性遗传性疾病,多散发存在,以易受压部位周围神经损害为主要临床表现,临床症状多样,常易漏诊,基因检测可明确诊断。本文将从3个临床病例,结合既往文献报道对HNPP进行讨论。
文摘3-O-beta-D-xylopyranosyl-6-O-beta-D-glucopyranosyl-cycloastragenol （astragaloside IV）, the main active component of the traditional Chinese medicine astragalus membranaceus, has been shown to be neuroprotective. This study investigated whether astragaloside IV could promote the repair of injured sciatic nerve. Denervated sciatic nerve of mice was subjected to anastomosis. The mice were intraperitoneally injected with 10, 5, 2.5 mg/kg astragaloside IV per day for 8 consecutive days Western blot assay and real-time PCR results demonstrated that growth-associated protein-43 ex- pression was upregulated in mouse spinal cord segments L4-6 after intervention with 10, 5, 2.5 mg/kg astragaloside IV per day in a dose-dependent manner. Luxol fast blue staining and elec- trophysiological detection suggested that astragaloside IV elevated the number and diameter of myelinated nerve fibers, and simultaneously increased motor nerve conduction velocity and action potential amplitude in the sciatic nerve of mice. These results indicated that astragaloside IV con- tributed to sciatic nerve regeneration and functional recovery in mice. The mechanism underlying this effect may be associated with the upregulation of growth-associated protein-43 expression.
基金funded by the National Natural Science Foundation of China, grant No. 81071001 and 30600200
文摘We used the allele-specific PCR-double digestion method on peripheral myelin protein 22 （PMP22） to determine duplication and deletion mutations in the proband and family members of one family with Charcot-Marie-Tooth disease type 1 and one family with hereditary neuropathy with liability to pressure palsies. The proband and one subclinical family member from the Charcot-Marie-Tooth disease type 1 family had a PMP22 gene duplication; one patient from the hereditary neuropathy with liability to pressure palsies family had a PMP22 gene deletion. Electron microscopic analysis of ultrathin sections of the superficial peroneal nerve from the two probands demonstrated demyelination and myelin sheath hyperplasia, as well as an ＇onion-like＇ structure in the Charcot-Marie-Tooth disease type 1A patient. We observed an irregular thickened myelin sheath and ＇mouse-nibbled＇-Iike changes in the patient with hereditary neuropathy with liability to pressure palsies. In the Charcot-Marie-Tooth disease type 1A patient, nerve electrophysiological examination revealed moderate-to-severe reductions in the motor and sensory conduction velocities of the bilateral median nerve, ulnar nerve, tibial nerve, and sural nerve. Moreover, the compound muscle action potential amplitude was decreased. In the patient with hereditary neuropathy with liability to pressure palsies, the nerve conduction velocity of the bilateral tibial nerve and sural nerve was moderately reduced, and the nerve conduction velocity of the median nerve and ulnar nerve of both upper extremities was slightly reduced.
文摘目的探讨遗传性压力易感性周围神经病（hereditary neuropathy with liability to pressurepalsies，HNPP）的临床、神经电生理及基因特点，为该病的诊断提供依据。方法对1个家系的4例患者进行临床特点总结，行电生理检查和基因检测。结果4例患者均表现为反复发作的周围神经受到轻微牵拉或压迫后出现运动感觉障碍，电生理检查示广泛性多发性的周围神经潜伏期延长，传导速度减慢，易卡压部位出现传导阻滞。基因检测示PMP22基因缺失突变。结论HNPP多以神经易卡压部位发病，表现为受累神经支配区的运动感觉异常，神经电生理表现为广泛神经脱髓鞘损伤，基因检测能确诊。
