C1q, a small molecule with high impact on brain development: putative role for aging processes and the occurrence of Alzheimer’s disease
Christian Rupprecht, Rainer Rupprecht, Gerhard Rammes
Abstract
Numerous proteins have been suggested to play a role in neurodegenerative disorders such as Alzheimer's disease (AD).A well-known protein, the complement protein C1q, has meanwhile entered the field and might stimulate further research in this area.C1q is a small molecule in the shape of a bunch of flowers [1] and is widely known for its role within the native immune system.As initiator of the antibody-dependent pathway it recognizes pathogenic structures in the blood stream, which in turn promotes their tagging and ultimately phagocytosis.For that reason C1q is also known as an "eat me" signal.Nowadays, emerging studies indicate that C1q may play a similar role within the brain.This in turn includes on the one hand a physiological function during brain development and, on the other hand, under pathological conditions, e.g., acute brain damage or AD, C1q may even promote neurodegeneration.