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1.  Mitochondrial abnormalities and low grade inflammation are present in the skeletal muscle of a minority of patients with amyotrophic lateral sclerosis; an observational myopathology study 
Background
Amyotrophic lateral sclerosis (ALS) is a primary progressive neurodegenerative disease characterised by neuronal loss of lower motor neurons (in the spinal cord and brainstem) and/or upper motor neurons (in the motor cortex) and subsequent denervation atrophy of skeletal muscle.
Aim
A comprehensive examination of muscle pathology from a cohort of clinically confirmed ALS patients, including an investigation of inflammation, complement activation, and deposition of abnormal proteins in order to compare them with findings from an age-matched, control group.
Material and methods
31 muscle biopsies from clinically confirmed ALS patients and 20 normal controls underwent a comprehensive protocol of histochemical and immunohistochemical stains, including HLA-ABC, C5b-9, p62, and TDP-43.
Results
Neurogenic changes were confirmed in 30/31 ALS cases. In one case, no neurogenic changes could be detected. Muscle fibre necrosis was seen in 5/31 cases and chronic mononuclear inflammatory cell infiltration in 5/31 (2 of them overlapped with those showing muscle necrosis). In four biopsies there was an increase in the proportion of cytochrome oxidase (COX) negative fibres (2-3%). p62 faintly stained cytoplasmic bodies in eight cases and none were immunoreactive to TDP-43.
Conclusion
This large series of muscle biopsies from patients with ALS demonstrates neurogenic atrophy is a nearly uniform finding and that mild mitochondrial abnormalities and low-grade inflammation can be seen and do not rule out the diagnosis of ALS. These findings could lend support to the notion that ALS is a complex and heterogeneous disorder.
doi:10.1186/s40478-014-0165-z
PMCID: PMC4297389  PMID: 25510661
Amyotrophic lateral Sclerosis; Mitochondria; Inflammation; Pathology and Muscle
2.  Deletion of galectin-3 exacerbates microglial activation and accelerates disease progression and demise in a SOD1G93A mouse model of amyotrophic lateral sclerosis 
Brain and Behavior  2012;2(5):563-575.
Galectins are pleiotropic carbohydrate-binding lectins involved in inflammation, growth/differentiation, and tissue remodeling. The functional role of galectins in amyotrophic lateral sclerosis (ALS) is unknown. Expression studies revealed increases in galectin-1 mRNA and protein in spinal cords from SOD1G93A mice, and in galectin-3 and -9 mRNAs and proteins in spinal cords of both SOD1G93A mice and sporadic ALS patients. As the increase in galectin-3 appeared in early presymptomatic stages and increased progressively through to end stage of disease in the mouse, it was selected for additional study, where it was found to be mainly expressed by microglia. Galectin-3 antagonists are not selective and do not readily cross the blood–brain barrier; therefore, we generated SOD1G93A/Gal-3−/− transgenic mice to evaluate galectin-3 deletion in a widely used mouse model of ALS. Disease progression, neurological symptoms, survival, and inflammation were assessed to determine the effect of galectin-3 deletion on the SOD1G93A disease phenotype. Galectin-3 deletion did not change disease onset, but resulted in more rapid progression through functionally defined disease stages, more severely impaired neurological symptoms at all stages of disease, and expiration, on average, 25 days earlier than SOD1G93A/Gal-3+/+ cohorts. In addition, microglial staining, as well as TNF-α, and oxidative injury were increased in SOD1G93A/Gal-3−/− mice compared with SOD1G93A/Gal-3+/+ cohorts. These data support an important functional role for microglial galectin-3 in neuroinflammation during chronic neurodegenerative disease. We suggest that elevations in galectin-3 by microglia as disease progresses may represent a protective, anti-inflammatory innate immune response to chronic motor neuron degeneration.
doi:10.1002/brb3.75
PMCID: PMC3489809  PMID: 23139902
Alternative activation; amyotrophic lateral sclerosis; microglia; motor neuron disease; SOD1
3.  New Treatments in Amyotrophic Lateral Sclerosis 
Neuropsychopharmacology  2010;36(1):370-372.
doi:10.1038/npp.2010.140
PMCID: PMC3055527  PMID: 21116264
4.  Loss of β-III spectrin leads to Purkinje cell dysfunction recapitulating the behaviour and neuropathology of SCA5 in humans 
Mutations in SPTBN2, the gene encoding β-III spectrin, cause spinocerebellar ataxia type 5 in humans (SCA5), a neurodegenerative disorder resulting in loss of motor coordination. How these mutations give rise to progressive ataxia and what the precise role β-III spectrin plays in normal cerebellar physiology are unknown. We developed a mouse lacking full length β-III spectrin and found that homozygous mice reproduced features of SCA5 including gait abnormalities, tremor, deteriorating motor coordination, Purkinje cell loss and cerebellar atrophy (molecular layer thinning). In vivo analysis reveals an age-related reduction in simple spike firing rate in surviving β-III−/− Purkinje cells while in vitro studies show these neurons to have reduced spontaneous firing, smaller sodium currents and dysregulation of glutamatergic neurotransmission. Our data suggest an early loss of EAAT4- (protein interactor of β-III spectrin) and subsequent loss of GLAST-mediated uptake may play a role in neuronal pathology. These findings implicate a loss of β-III spectrin function in SCA5 pathogenesis and indicate there are at least two physiological effects of β-III spectrin loss that underpin a progressive loss of inhibitory cerebellar output, namely an intrinsic Purkinje cell membrane defect due to reduced sodium currents and alterations in glutamate signaling.
doi:10.1523/JNEUROSCI.6065-09.2010
PMCID: PMC2857506  PMID: 20371805
ataxia; cerebellum; motor coordination; glutamate transporters; excitotoxicity; neurodegeneration
5.  Analysis of IFT74 as a candidate gene for chromosome 9p-linked ALS-FTD 
BMC Neurology  2006;6:44.
Background
A new locus for amyotrophic lateral sclerosis – frontotemporal dementia (ALS-FTD) has recently been ascribed to chromosome 9p.
Methods
We identified chromosome 9p segregating haplotypes within two families with ALS-FTD (F476 and F2) and undertook mutational screening of candidate genes within this locus.
Results
Candidate gene sequencing at this locus revealed the presence of a disease segregating stop mutation (Q342X) in the intraflagellar transport 74 (IFT74) gene in family 476 (F476), but no mutation was detected within IFT74 in family 2 (F2). While neither family was sufficiently informative to definitively implicate or exclude IFT74 mutations as a cause of chromosome 9-linked ALS-FTD, the nature of the mutation observed within F476 (predicted to truncate the protein by 258 amino acids) led us to sequence the open reading frame of this gene in a large number of ALS and FTD cases (n = 420). An additional sequence variant (G58D) was found in a case of sporadic semantic dementia. I55L sequence variants were found in three other unrelated affected individuals, but this was also found in a single individual among 800 Human Diversity Gene Panel samples.
Conclusion
Confirmation of the pathogenicity of IFT74 sequence variants will require screening of other chromosome 9p-linked families.
doi:10.1186/1471-2377-6-44
PMCID: PMC1764752  PMID: 17166276

Results 1-5 (5)