Reduced expression of BTBD10 in anterior horn cells with Golgi fragmentation and pTDP-43-positive inclusions in patients with sporadic amyotrophic lateral sclerosis.

Overexpression of BTBD10 (BTB/POZ domain-containing protein 10) suppresses G93A-superoxide dismutase 1 (SOD1)-induced motor neuron death in a cell-based amyotrophic lateral sclerosis (ALS) model. In the present study, paraffin sections of spinal cords from 13 patients with sporadic ALS and 10 with non-ALS disorders were immunostained using a polyclonal anti-BTBD10 antibody. Reduced BTBD10 expression in the anterior horn cells was more frequent in spinal cords from ALS patients than in cords from patients with non-ALS disorders. We further investigated the relationship between the level of BTBD10 immunoreactivity and the morphology of the Golgi apparatus (GA) and the presence of phosphorylated TAR-DNA-binding protein 43 (pTDP-43). Mirror sections of spinal cords from five sporadic ALS cases were immunostained with antibodies against BTBD10 and trans-Golgi-network (TGN)-46 or pTDP-43. Whereas 89.7-96.5% of the neurons with normal BTBD10 immunoreactivity showed normal GA morphology and no pTDP-43 cytoplasmic aggregates, 86.2-94.3% of the neurons with reduced BTBD10 expression showed GA fragmentation and abnormal pTDP-43 aggregates. These findings suggest that reduced BTBD10 expression is closely linked to the pathogenesis of sporadic ALS.