Viagra Users Are 69% Less Likely to Develop Alzheimer’s

Viagra could be a useful treatment against Alzheimer’s disease, according to a US study. Alzheimer’s disease, the most common form of age-related dementia, affects hundreds of millions of people worldwide. Despite mounting numbers of cases, however, there is currently no effective treatment.

Using a large gene-mapping network, researchers at the Cleveland Clinic integrated genetic and other data to determine which of more than 1,600 Food and Drug Administration-approved drugs could be an effective treatment for Alzheimer’s disease. They gave higher scores to drugs that target both amyloid and tau – two hallmarks of Alzheimer’s – compared with drugs that targeted just one or the other.

US scientists say users of sildenafil – the generic name for Viagra – are 69% less likely to develop the form of dementia than non-users

“Sildenafil, which has been shown to significantly improve cognition and memory in preclinical models, presented as the best drug candidate,” said Dr Feixiong Cheng, the study lead.

Researchers then used a database of claims from more than 7 million people in the US to examine the relationship between sildenafil and Alzheimer’s disease outcomes by comparing sildenafil users to non-users.

They found sildenafil users were 69% less likely to develop Alzheimer’s disease than non-sildenafil users after six years of follow-up. To further explore the drug’s potential effect on Alzheimer’s disease, researchers developed a lab model that showed that sildenafil increased brain cell growth and targeted tau proteins, offering insights into how it might influence disease-related brain changes. Cheng cautioned that the study does not demonstrate a causal relationship between sildenafil and Alzhemer’s disease. Randomised clinical trials involving both sexes with a placebo control were needed to determine sildenafil’s efficacy, he said.

Dr Ivan Koychev, a senior clinical researcher at the University of Oxford, who was not involved in the study, said it was “an exciting development” because “it points to a specific drug which may offer a new approach to treating the condition”.

Prof Tara Spires-Jones, deputy director of the Centre for Discovery Brain Sciences at the University of Edinburgh, said there were several important limitations to consider. “While these data are interesting scientifically, based on this study, I would not rush out to start taking sildenafil as a prevention for Alzheimer’s disease.”

Dr Susan Kohlhaas, director of research at Alzheimer’s Research UK, said: “Being able to repurpose a drug already licensed for other health conditions could help speed up the drug discovery process and bring about life-changing dementia treatments sooner. “Importantly, this research doesn’t prove that sildenafil is responsible for reducing dementia risk, or that it slows or stops the disease. The only way to test this would be in a large-scale clinical trial measuring sildenafil effect against the usual standard of care.”

The findings were published in Nature Aging.

Source: https://www.theguardian.com/

Blood Iron Levels Are Key To Slowing Ageing

Genes that could help explain why some people age at different rates to others have been identified by scientists. The international study using genetic data from more than a million people suggests that maintaining healthy levels of iron in the blood could be a key to ageing better and living longer. The findings could accelerate the development of drugs to reduce age-related diseases, extend healthy years of life and increase the chances of living to old age free of disease, the researchers say.

Scientists from the University of Edinburgh and the Max Planck Institute for Biology of Ageing in Germany focused on three measures linked to biological ageinglifespan, years of life lived free of disease (healthspan), and being extremely long–lived (longevity). Biological ageing – the rate at which our bodies decline over time – varies between people and drives the world’s most fatal diseases, including heart disease, dementia and cancers. The researchers pooled information from three public datasets to enable an analysis in unprecedented detail. The combined dataset was equivalent to studying 1.75 million lifespans or more than 60,000 extremely long-lived people. The team pinpointed ten regions of the genome linked to long lifespan, healthspan and longevity. They also found that gene sets linked to iron were overrepresented in their analysis of all three measures of ageing. The researchers confirmed this using a statistical method – known as Mendelian randomisation – that suggested that genes involved in metabolising iron in the blood are partly responsible for a healthy long life.

Blood iron is affected by diet and abnormally high or low levels are linked to age-related conditions such as Parkinson’s disease, liver disease and a decline in the body’s ability to fight infection in older age. The researchers say that designing a drug that could mimic the influence of genetic variation on iron metabolism could be a future step to overcome some of the effects of ageing, but caution that more work is required.

Anonymised datasets linking genetic variation to healthspan, lifespan, and longevity were downloaded from the publicly available Zenodo, Edinburgh DataShare and Longevity Genomics servers.

We are very excited by these findings as they strongly suggest that high levels of iron in the blood reduces our healthy years of life, and keeping these levels in check could prevent age-related damage. We speculate that our findings on iron metabolism might also start to explain why very high levels of iron-rich red meat in the diet has been linked to age-related conditions such as heart disease”, said Dr Paul Timmers from the Usher Institute.

The study was funded by the Medical Research Council and is published in the journal Nature Communications.

Source: https://www.ed.ac.uk/