Tech Explorist By Pranjal Mehar 12/31/2022
A clue to the molecular cause of Alzheimer’s.In postmenopausal women, depletion of estrogen causes excessive elevation of nitric oxide (NO) in the brain and thus generates S-nitrosylated complement factor C3 (abbreviated SNO-C3). SNO-C3 triggers activated microglial cells, the innate immune cells in the brain, to phagocytose (or ‘eat’) neuronal synapses—the connections that mediate signaling between nerve cells in the brain. This aberrant chemical biology process results in synapse loss, leading to cognitive decline in Alzheimer’s disease. Credit: Chang-ki Oh and Stuart Lipton, Scripps Research
Neurodegenerative diseases, characterized by a progressive loss of brain function, result primarily from synaptic loss and neuronal cell death in the central nervous system. Alzheimer’s disease (AD) is arguably the most common neurodegenerative disorder leading to dementia.
The shortcomings of treatments reflect that scientists have never fully understood how Alzheimer’s develops. Scientists also don’t know why women account for nearly two-thirds of cases.
Researchers at MIT and Scripps Research have discovered a hint to the molecular aetiology of Alzheimer’s disease; this clue may also explain why women are more susceptible to the disease.
Researchers discovered a particularly harmful, chemically modified form of an inflammatory immune protein called complement C3 was present at much higher levels in the brains of women who had died with the disease compared to men who had died with the disease. They also showed that estrogen—which drops in production during menopause—typically protects against the creation of this form of complement C3.
Study senior author Stuart Lipton, MD, Ph.D., professor and Step Family Foundation Endowed Chair in the Department of Molecular Medicine at Scripps Research and a clinical neurologist in La Jolla, California, said,
“Our new findings suggest that chemical modification of a component of the complement system helps drive Alzheimer’s, and may explain, at least in part, why the disease predominantly affects women.”More:
https://www.techexplorist.com/women-likely-alzheimers/55729/