Inclusion body myositis, sporadic amyloid

Oxidative damage to cells is a common phenomenon, and quality control of modified proteins is important to maintain normal cellular functions. In the cytoplasm, nucleus, and endoplasmic reticulum, the proteasome is involved in the removal of various types of proteins such as ubiquinated, misfolded, or unfolded proteins, and oxidized proteins. Abnormal inhibition of proteasome may contribute to neuro-degenerative diseases such as Alzheimer disease, Parkinson disease, Lewy body dementia, and Huntington disease [31-40]. Neuromuscular diseases, such as sporadic inclusion-body myositis (s-IBM) share several phenotypes described in the brain tissues of Alzheimer and Parkinson disease patients [41]. One such similarity to Alzheimer disease is the accumulation of amyloid-P (AP), phosphory-lated tau (p-tau), and ubiquitin, which are often found within these aggregates [42, 43]. In s-IBM patients, significant proteasome abnormalities were identified including, increased 26 S proteasome expression and abnormal accumulation of 26S proteasome, but reduced proteasome activities [44]. The inverse relationship between increased expression... 

Fratta P, Engel WK, McFerrin J et al. (2005) Protea-some inhibition and aggresome formation in sporadic inclusion-body myositis and in amyloid-beta precursor protein-overexpressing cultured human muscle fibers. Am J Pathol 167(2), 517-526. 

Vattemi G, Nogalska A, King Engel W et al. (2009) Amyloid-beta42 is preferentially accumulated in muscle fibers of patients with sporadic inclusion-body myositis. Acta Neuropathol 117, 569-574. 

Vattemi G, Kefi M, Engel WK et al. (2003) Nicastrin, a novel protein partidpating in amyloid-beta production, is overexpressed in sporadic inclusion-body myositis muscle. Neurology 60, A315. 

Lunemann JD, Schmidt J, Schmid D et al. (2007) Beta-amyloid is a substrate of autophagy in sporadic inclusion body myositis. Ann Neurol 61, 476 83. 

Askanas V, Sarkozi E, Alvarez RB et al. (1996) Superoxide dismutase-1 gene and protein in vacuolated muscle fibers of sporadic inclusion-body myositis, hereditary inclusion-body myopathy, and cultured human muscle after beta-amyloid precursor protein gene transfer. Neurology 46, A487. 

Muth IE, Barthel K, Bahr M et al. (2009) Proinflam -matory cell stress in sporadic inclusion body myositis muscle overexpression of aB-crystallin is associated with amyloid precursor protein and accumulation of p-amyloid. J Neurol Neurosurg Psychiatry 80, 1344-1349. 

Terracciano C, Engel W, Askanas V. (2008) In sporadic inclusion-body myositis muscle biopsies, cytochrome oxidase (COX) negative muscle fibers do not correlate with either inflammation or with aggregates containing amyloid-beta or phosphorylated tau. Neurology 70, A304. 

Wojcik S, Paciello O, Engel WK et al. (2007) In sporadic inclusion-body myositis muscle fiber cytoplasm, cytochrome c aggregates with a-synudein and amyloid-beta precursor protein, but does not activate caspase-3. Neuromuscul Disord 17, 853. 

Specifically, the similarities of sporadic inclusion-body myositis with the Alzheimer brain include accumulations of amyloid-P, phosphorylated tau and numerous other "Alzheimer disease-characteristic" proteins. The similarities of inclusion-body myositis with Parkinson disease include accumulations of a-synuclein, parkin, DJ-1, and other abnormalities. These similarities suggest that (a) the aging-associated degenerative-muscle and degenerative-brain diseases may share certain pathogenic steps and (b) knowledge of one disease might help elucidate the cause and treatment of the others. And, despite the remarkable molecular sim-... 

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