Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026838 (spasticity)
 6,471 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hereditary spastic paraplegia (HSP) is a neurodegenerative disease characterized by lower-limb spasticity, hyperreflexia, progressive spastic gait abnormalities, and an extensor-plantar response. It is genetically very heterogeneous, with 28 Human Genome Organisation (HUGO)-approved IDs in the database (last search: August 8, 2004). Following the identification of the SPG6 gene, NIPA1, we have identified two novel mutations, c.316G>C and c.316G>A, in two independent Chinese families linked to the SPG6 locus. These two mutations would cause a p.G106R substitution, and cosegregated with the disease. Structural predictions suggest that p.G106 is located in the third transmembrane domain of the protein, and that the mutant p.G106R disrupts this structure, causing the intramembrane loop to descend into the cytoplasm. Our results identify two novel mutations responsible for HSP and suggest that c.316 of theNIPA1 gene may be a mutational hotspot.
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PMID:Distinct novel mutations affecting the same base in the NIPA1 gene cause autosomal dominant hereditary spastic paraplegia in two Chinese families. 1564 3

Pure hereditary spastic paraplegias are characterized by isolated and progressive spasticity in the lower limbs. We mapped the spastic paraplegia 28 (SPG28) locus to chromosome 14q21.3-q22.3 in a Moroccan family with autosomal recessive hereditary spastic paraplegia. Affected patients experienced development of progressive spastic gait during childhood and required help walking in their early 40s. Nine additional hereditary spastic paraplegia families were not linked to this locus, demonstrating further genetic heterogeneity. No mutations were found in exons of GCH1 and SPG3A, two genes from the candidate region involved in movement disorders.
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PMID:Mapping of a new form of pure autosomal recessive spastic paraplegia (SPG28). 1578 64

Hereditary spastic paraplegia (HSP) is a genetically heterogeneous group of neurodegenerative disorders characterized by progressive lower extremity weakness and spasticity. HSP pathology involves axonal degeneration that is most pronounced in the terminal segments of the longest descending (pyramidal) and ascending (dorsal columns) tracts. In this study, we compared spinal cord magnetic resonance imaging (MRI) in 13 HSP patients with four different types of autosomal dominant hereditary spastic paraplegia (SPG3A, SPG4, SPG6, and SPG8) with age-matched control subjects. The cross-section area of HSP subjects at cervical level C2 was 59.42 +/- 12.57 mm2 and at thoracic level T9 was 28.58 +/- 5.25 mm2. Both of these values were less than in the healthy controls (p < 0.001). The degree of cord atrophy was more prominent in patients with SPG6 and SPG8 who had signs of severe cord atrophy (47.60 +/- 6.58 mm2 at C2, 21.40 +/- 2.4 mm2 at T9) than in subjects with SPG3 and SPG4 (66.0 +/- 8.94 mm2 at C2, p < 0.02; 31.75 +/- 2.76 mm2 at T9, p < 0.001). These observations indicate that spinal cord atrophy is a common finding in the four genetic types of HSP. Spinal cord atrophy was more severe in SPG6 and SPG8 HSP subjects than in other types of HSP we studied. This may suggest a different disease mechanism with more prominent axonal degeneration in these two types of HSP when compared with HSP due to spastin and atlastin mutations.
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PMID:Spinal cord magnetic resonance imaging in autosomal dominant hereditary spastic paraplegia. 1614 70

Hereditary spastic paraplegias (HSPs) are neurodegenerative diseases caused by mutations in more than 20 genes, which lead to progressive spasticity and weakness of the lower limbs. The most frequently mutated gene causing autosomal dominant HSP is SPG4, which encodes spastin, a protein that belongs to the family of ATPases associated with various cellular activities (AAAs). A number of studies have suggested that spastin regulates microtubule dynamics. We have studied the ATPase activity of recombinant human spastin and examined the effect of taxol-stabilized microtubules on this activity. We used spastin translated from the second ATG and provide evidence that this is the physiologically relevant form. We showed that microtubules enhance the ATPase activity of the protein, a property also described for katanin, an AAA of the same spastin subgroup. Furthermore, we demonstrated that human spastin has a microtubule-destabilizing activity and can bundle microtubules in vitro, providing new insights into the molecular pathogenesis of HSP.
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PMID:Human spastin has multiple microtubule-related functions. 1621 33

Hereditary spastic paraplegias (HSPs) are a group of neurodegenerative diseases characterized by progressive weakness and spasticity of the lower limbs. Dominant mutations in the human SPG4 gene, encoding spastin, are responsible for the most frequent form of HSP. Spastin is an ATPase that binds microtubules and localizes to the spindle pole and distal axon in mammalian cell lines. Furthermore, its Drosophila homolog, Drosophila spastin (Dspastin), has been recently shown to regulate microtubule stability and synaptic function at the Drosophila larval neuromuscular junction. Here we report the generation of a spastin-linked HSP animal model and show that in Drosophila, neural knockdown of Dspastin and, conversely, neural overexpression of Dspastin containing a conserved pathogenic mutation both recapitulate some phenotypic aspects of the human disease, including adult onset, locomotor impairment, and neurodegeneration. At the subcellular level, neuronal expression of both Dspastin RNA interference and mutant Dspastin cause an excessive stabilization of microtubules in the neuromuscular junction synapse. In addition, we provide evidence that administration of the microtubule targeting drug vinblastine significantly attenuates these phenotypes in vivo. Our findings demonstrate that loss of spastin function elicits HSP-like phenotypes in Drosophila, provide novel insights into the molecular mechanism of spastin mutations, and raise the possibility that therapy with Vinca alkaloids may be efficacious in spastin-associated HSP and other disorders related to microtubule dysfunction.
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PMID:Disease-related phenotypes in a Drosophila model of hereditary spastic paraplegia are ameliorated by treatment with vinblastine. 1627 9

The hereditary spastic paraplegias (HSPs) comprise a large group of inherited neurologic disorders. HSP is classified according to the mode of inheritance, the HSP locus when known, and whether the spastic paraplegia syndrome occurs alone or is accompanied by additional neurologic or systemic abnormalities. Analysis of 11 recently discovered HSP genes provides insight into HSP pathogenesis. Hereditary spastic paraplegia is a clinical diagnosis for which laboratory confirmation is sometimes possible, and careful exclusion of alternate and co-existing disorders is an important element in HSP diagnosis. Treatment for HSP is presently limited to symptomatic reduction of muscle spasticity, reduction in urinary urgency, and strength and gait improvement through physical therapy. Prenatal genetic testing in HSP is possible for some individuals with the increasing availability of HSP gene analysis.
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PMID:Hereditary spastic paraplegia. 1646 73

Hereditary spastic paraplegias (HSPs) are a heterogeneous group of neurodegenerative disorders leading to progressive spasticity of the lower limbs. Clinically, HSPs are divided into "pure" and "complicated" forms. In pure HSP, the spasticity of the lower limbs is the sole symptom, whereas in complicated forms additional neurological and non-neurological features are observed. Genetically, HSPs are divided into autosomal dominant (AD), autosomal recessive (AR) and X-linked (XL) forms. Up to date, 30 different HSPs are linked to different chromosomal loci and 11 genes could be defined for AR-HSP, AD-HSP and XL-HSP. SPG11, an AR-HSP (synonym: HSP11), is a complicated HSP associated with a slowly progressive spastic paraparesis, mental impairment and the development of a thin corpus callosum (TCC) during the course of the disease. SPG11 has been previously linked to chromosomal region 15q13 - 15. First, we applied rigid diagnostic criteria to systematically examine 20 Turkish families with autosomal recessive HSP for characteristic features of SPG11. We detected four large Turkish families with AR-HSP and TCC consistent with SPG11. Subsequent genetic linkage analysis of those 4 families refines the SPG11 locus further down to a small region of 2.93 cM with a maximum lod score of 11.84 at marker D15S659 and will guide further candidate gene analysis.
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PMID:Further clinical and genetic characterization of SPG11: hereditary spastic paraplegia with thin corpus callosum. 1677 2

Hereditary spastic paraplegia (HSP) is a group of genetically heterogeneous neurodegenerative disorders characterized by slowly progressive spasticity and weakness of the lower limbs. HSP is caused by failure of development or selective degeneration of the corticospinal tracts, which contain the longest axons in humans. The most common form of HSP is caused by mutations of the spastin gene (SPAST), located on chromosome 2p21-p22, which encodes spastin, one of the ATPases associated with diverse cellular activities (AAA). In this study, we detected four causative mutations of SPAST among 14 unrelated patients with spastic paraplegia. Two missense mutations (1447A-->G, 1207C-->G) and two deletion mutations (1465delT, 1475-1476delAA) were located in the AAA cassette region. Three of these four mutations were novel. Previous reports and our results suggest that the frequency of SPAST mutations is higher among Japanese patients with autosomal dominant HSP, although SPAST mutations are also observed in patients with sporadic spastic paraplegia.
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PMID:Four mutations of the spastin gene in Japanese families with spastic paraplegia. 1678 34

Hereditary spastic paraplegia (HSP) is a collection of neurological disorders characterized by developmental failure or degeneration of motor axons in the corticospinal tract and progressive lower limb spasticity. SPG4 mutations are the most common cause of autosomal dominant HSP and Spastin (the SPG4 gene product) is a microtubule severing protein that shares homology with katanin, the microtubule severing activity of which promotes axon growth in cultured neurons. Given the sequence and functional similarity between spastin and katanin, we hypothesized that spastin promotes the dynamic disassembly and remodelling of microtubules required for robust, properly directed motor axon outgrowth. To investigate this hypothesis, we cloned the zebrafish spg4 orthologue and used morpholino antisense oligonucleotides directed against the translation start site and the intron 7-8 splice donor site to knock down spastin function in the developing zebrafish embryo. Reduced spg4 function caused dramatic defects in motor axon outgrowth without affecting the events driving the initial specification of motor neurones. Other neuronal subtypes also exhibited a requirement for spg4 function, since spg4 knock down caused both widespread defects in neuronal connectivity and extensive CNS-specific apoptosis. Our results reveal a critical requirement for spastin to promote axonal outgrowth during embryonic development, and they validate the zebrafish embryo as a novel model system to dissect the pathogenetic mechanisms underlying HSP. Taken together with other recent studies, our findings suggest that axon outgrowth defects may be a common feature of childhood SPG3A and SPG4 cases.
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PMID:The microtubule-severing protein Spastin is essential for axon outgrowth in the zebrafish embryo. 1689 13

Hereditary spastic paraplegias (HSPs) are a group of single-gene disorders characterised by degeneration of the corticospinal tract axons, leading to bilateral, symmetrical, slowly-progressive spastic paraparesis, predominantly of the lower extremities. So far, ~ 30 different chromosomal HSP loci have been identified by genetic linkage analysis. Defects in intracellular trafficking and transport in myelination and abnormalities of mitochondrial proteins have been involved in HSP pathogenesis. At present, treatment of the HSPs is primarily directed symptomatically toward reducing muscle spasticity. Yet, recent progresses in the identification of HSP mutations are providing formidable tools to pharmacogenetic approaches of drug discovery, validation and prediction of individual response.
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PMID:Hereditary spastic paraplegia: clinical genomics and pharmacogenetic perspectives. 1702 Apr 12


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