Elevated membrane cholesterol disrupts lysosomal degradation to induce A β accumulation: the potential mechanism underlying augmentation of Aβ pathology by type 2 diabetes mellitus.

Elevated membrane cholesterol disrupts lysosomal degradation to induce Aβ accumulation: the potential mechanism underlying augmentation of Aβ pathology by type 2 diabetes mellitus. Am J Pathol. 2018 Nov 15;: Authors: Takeuchi S, Ueda N, Suzuki K, Shimozawa N, Yasutomi Y, Kimura N Abstract Endocytic membrane trafficking system is altered in the brains of early-stage Alzheimer disease (AD) patients, and endocytic disturbance affects the metabolism of β-amyloid protein (Aβ), a key molecule in AD pathogenesis. It is widely accepted that type 2 diabetes mellitus (T2DM) is one of the strongest risk factors for development of AD. Supporting this link, experimentally induced T2DM enhances AD pathology in various animal models. Spontaneous T2DM also enhances Aβ pathology with severe endocytic pathology, even in nonhuman primate brains. However, it remains unclear how T2DM accelerates Aβ pathology. Here, we demonstrate that cholesterol metabolism-related protein levels are increased and that membrane cholesterol level is elevated in spontaneous T2DM-affected cynomolgus monkey brains. Moreover, in vitro studies that manipulate cellular cholesterol reveal that elevated membrane cholesterol disrupts lysosomal degradation and enhances chemical-induced endocytic disturbance, resulting in great accumulation of Aβ in Neuro2a cells. These findings suggest that an alteration of cerebral cholesterol metabolism may be responsible for augmentation ...
Source: The American Journal of Pathology - Category: Pathology Authors: Tags: Am J Pathol Source Type: research