Researchers at Arizona State University and Banner Alzheimer’s Institute have made a groundbreaking discovery linking cytomegalovirus (HCMV) to the development of a subset of Alzheimer’s disease (AD). The study, published in the journal Alzheimer’s & Dementia, suggests that 25% to 45% of people with AD may be affected by this unique subtype of the disease.
The connection between HCMV and AD is thought to occur when the virus lingers in the gut and travels to the brain via the vagus nerve. Once in the brain, HCMV triggers immune cells called microglia to express a gene called CD83, leading to inflammation and neuronal damage. This process is similar to what has been observed in postmortem brains of AD patients.
The researchers’ findings align with earlier studies suggesting that an infection may play a role in the development of this form of AD. The new study confirms the presence of HCMV antibodies in the intestines and cerebrospinal fluid of AD patients, as well as HCMV in the vagus nerve. This suggests that HCMV may reach the brain by traveling through this neural pathway.
The discovery has significant implications for the diagnosis and treatment of AD. The researchers are now developing a blood test to identify patients with chronic intestinal HCMV infection, which could support further research into the impact of viruses on brain health and neurodegeneration. This could also lead to the use of existing antiviral medications to treat or prevent this form of AD.
Source: https://www.insideprecisionmedicine.com/topics/translational-research/study-suggests-cytomegalovirus-could-contribute-to-alzheimers-pathology-in-certain-individuals