Diabetes medicine might reduce effects of Alzheimer's disease

by Stephen McDermott for The Journal:Alzheimer's patients who take diabetes drugs show considerably fewer markers of the disease according to a new study looking at how to treat the neurodegenerative condition.The study, carried out by researchers at Mount Sinai Hospital in New York, examined what happens in the pathways of brain tissue and cells lining blood vessels in the brains of Alzheimer’s patients who were also treated with diabetes medication.It found that those who take diabetes drugs tend to have lower markers of abnormal microvasculature and disregulated gene expressions in their brains compared to those who don’t.According to the researchers, the findings suggest that targeting the brain’s capillary system could have beneficial effects for Alzheimer’s patients.The research was underaken because many elderly people who have diabetes also have brain changes that show the same hallmarks of Alzheimer’s disease.Insulin signalingTwo previous studies by Mount Sinai found that the brains of people with both Alzheimer’s disease and diabetes had fewer lesions associated with Alzheimer’s than the brains of people with Alzheimer’s disease who don’t have diabetes.Those results suggested that anti-diabetes drugs had a protective effect on the brains of Alzheimer’s patients.This time, the research team developed a method to separate brain capillaries from the tissue of 34 Alzheimer’s patients and type-2 diabetes who had been treated with anti-diabetes drugs.They compared them to tissue from the brains of 30 Alzheimer’s patients who did not have diabetes, as well as 19 people without Alzheimer’s or diabetes.Researchers subsequently examined the vessels and brain tissue separately to measure changes associated with Alzheimer’s disease in molecular RNA markers for brain capillary cells and insulin signaling.Molecular pathwaysLevels in about half of these markers were reduced in the vessels and brain tissue in the group of people with Alzheimer’s disease and diabetes.In Alzheimer’s patients who had been treated with anti-diabetes drugs, the vast majority of the RNA changes seen in Alzheimer’s disease were absent.“The results of this study are important because they give us new insights for the treatment of Alzheimer’s disease,” the study’s senior author, Vahram Haroutunian said.“This opens opportunities to conduct research trials on people using similar drugs or on drugs that have similar effects on the brains’ biological pathways and cell types identified in this study.”The study was published in PLOS One earlier this week, and hopes to inform future studies and potential new therapies targeting specific cells.The research team intends to study the drugs and their molecular pathways in greater detail using a combination of postmortem human brain cells and mouse models.Source: https://www.thejournal.ie/alzheimers-disease-treatment-diabetes-drugs-4319189-Nov2018/