Signaling Pathways in Neurodegeneration

Neurodegeneration is the progressive loss of specific subsets of neurons present in the central nervous system leading to cognitive disability, including dementia. Neurodegenerative diseases are usually characterized by the accumulation of misfolded proteins in the neuronal cells and malfunction of proteasomal, lysosomal, autophagosomal, or mitochondrial systems that ultimately lead to neurodegeneration. Emerging evidence suggests that dysregulation of cell signaling pathways plays a pivotal role in the pathogenesis of various neurodegenerative diseases. Here, we describe cell signaling pathways that have been well studied to play a major role in different neurodegenerative diseases. Alterations in these pathways in neuronal disorders have been reported to manifest at protein quality control level, impaired mitochondrial dynamics, dysregulated autophagy and lysosomal pathways, abnormal accumulation of stress granules, neuroinflammation, perturbed immune response, and synaptic toxicity. Understanding the role of various cell signaling pathways and their crosstalk and signal integration in the pathogenesis of neurodegenerative diseases at the molecular level is critical for the development of effective treatments for neurodegenerative disorders.