Cholesterol imbalance and neurotransmission defects in neurodegeneration

The brain contains the highest concentration of cholesterol in the human body, which emphasizes the importance of cholesterol in brain physiology. Cholesterol is involved in neurogenesis and synaptogenesis, and age-related reductions in cholesterol levels can lead to synaptic loss and impaired synaptic plasticity, which potentially contribute to neurodegeneration. The maintenance of cholesterol homeostasis in the neuronal plasma membrane is essential for normal brain function, and imbalances in cholesterol distribution are associated with various neurodegenerative disorders, including Alzheimer’s disease, Parkinson’s disease, and Huntington’s disease. This review aims to explore the molecular and pathological mechanisms by which cholesterol imbalance can lead to neurotransmission defects and neurodegeneration, focusing on four key mechanisms: (1) synaptic dysfunction, (2) alterations in membrane structure and protein clustering, (3) oligomers of amyloid beta (Aβ) protein, and (4) α-synuclein aggregation. Cholesterol, a substance crucial for the brain, can lead to diseases like Alzheimer’s and Parkinson’s when imbalanced. This review investigates how this imbalance causes brain cell degeneration, focusing on issues like communication breakdown and harmful protein build-up. The study combines findings from different experiments to understand cholesterol’s role in the brain. The review emphasizes the need for cholesterol balance for brain health and identifies potential treatment targets for neurodegenerative diseases. The main findings suggest that cholesterol imbalance disrupts brain cell communication and leads to harmful protein build-up, causing brain cell degeneration. The researchers conclude that focusing on cholesterol metabolism and distribution could lead to new treatments for these conditions. Future research may lead to treatments that correct cholesterol imbalances, possibly slowing or preventing neurodegenerative diseases. This summary was initially drafted using artificial intelligence, then revised and fact-checked by the author.