However, in the affected lower motor neurons, TDP-43 was never co-localized with expanded polyQ stretches or ATX3. At that time, we considered that there was little interaction between TDP-43 and expanded polyQ stretches in SCA3/MJD. In this connection, SALS-like ubiquitinated
filamentous inclusions may be observed in neurons of the cerebellar dentate nucleus in dentatorubral pallidoluysian atrophy MK-8669 solubility dmso (DRPLA), another polyQ disease. These inclusions can be recognized with anti-expanded polyQ antibody (1C2),[24] but not with anti-TDP-43 antibody. Recently, Elden et al. reported that ATX2 intermediate-length polyglutamine expansions are associated with ALS.[16] This is of considerable interest in terms of the molecular interactions between polyQ and TDP-43. ATX2 is a polyQ
protein that is mutated in SCA2, an autosomal-dominant neurological SB203580 ic50 disease, where CAG repeats are expanded in the SCA2 gene (ATXN2). It is known that patients with SCA2 sometimes show motor neuron disease phenotypes.[25] However, no pathological studies employing anti-TDP-43 antibody have been reported. Recently, we had an opportunity to examine in detail an autopsied patient with SCA2 using both 1C2 and anti-phosphorylated TDP-43 antibody (S409/410).[18] Briefly, the patient, a 52-year-old Japanese man, had developed speech disturbance as the initial symptom when in his 30s. At
the age of 46 years, he had been diagnosed as having SCA2 by DNA examination; the number of CAG repeats in ATXN2 was 42. Immunostaining with 1C2 revealed many widely distributed positive neuronal inclusions in the CNS (Fig. 1a). These inclusions were present frequently in the cytoplasm and rarely in the nuclei (Fig. 1b,c). Immunostaining with S409/410 also revealed positive NCIs appearing as linear wisp-like or skein-like inclusions (Fig. 1d), or dense bodies (Fig. 1e). In addition, cat’s eye-shaped Clomifene NIIs were observed in a few neurons (Fig. 1f) and coiled body-like cytoplasmic inclusions were detected in a few oligodendrocytes (Fig. 1g). As in the other polyglutamine diseases previously mentioned, TDP-43 inclusions and expanded polyQ stretches sometimes co-existed, but were never co-localized in the same neurons (Fig. 1h–j). TDP-43-positive NCIs were relatively widespread in the CNS, the distribution pattern somewhat resembling that of SALS type 1 (Nishihira et al.[20]) (Table 1). Apart from the distribution pattern, two important features were noteworthy. First, the TDP-43-positive NCIs were indistinguishable in morphology from those seen in SALS. Second, like SALS, apparent neurodegeneration was observed in the motor cortex and spinal anterior horns, but no TDP-43-positive NCIs were evident in the affected upper and lower motor neuron nuclei.