Neurodegeneration
The progressive loss of structure or function of neurons, leading to conditions such as Alzheimer's disease, Parkinson's disease, and ALS. Neuroprotective peptides that could slow or halt neurodegeneration are a major goal of research, though clinical breakthroughs remain limited.
Technical Context
Common neurodegenerative diseases: Alzheimer's (amyloid-β plaques + tau tangles → hippocampal/cortical neuronal loss → memory/cognitive decline), Parkinson's (α-synuclein Lewy bodies → substantia nigra dopaminergic neuron loss → motor symptoms), ALS (motor neuron degeneration → progressive paralysis), Huntington's (huntingtin polyQ expansion → striatal neuron loss → movement/cognitive/psychiatric symptoms), and multiple sclerosis (autoimmune demyelination → axonal degeneration). Shared pathological mechanisms: protein misfolding and aggregation, mitochondrial dysfunction, oxidative stress, neuroinflammation (microglial activation), excitotoxicity (glutamate-mediated calcium overload), and impaired autophagy. Peptide-based neuroprotection strategies: targeting protein aggregation (peptide inhibitors of amyloid-β or α-synuclein aggregation), enhancing neurotrophic support (BDNF mimetics, NGF mimetics), modulating neuroinflammation (anti-inflammatory peptides), and protecting mitochondria (elamipretide-type approaches applied to neurodegeneration — currently preclinical for CNS indications).