A new US study suggests what makes ‘SuperAgers’ unique are their large neurons. Researchers at Chicago’s Northwestern University who autopsied 24 brains, including 6 from people known as ‘SuperAgers’ – individuals aged 80 and older who score similarly to those aged 20-30 years younger in memory tests – found the SuperAgers had larger neurons than people almost 60 years their junior.
The scientists, whose study was reported in the Journal of Neuroscience, found the SuperAgers’ neurons did not have ‘tau tangles’ – a hallmark of Alzeheimer’s disease.
Study co-author Professor Tamar Gefen told medicalnewstoday.com: ‘For reasons that remain unknown, cell populations in the brain’s entorhinal cortex (ERC) are selectively vulnerable to ‘tau tangle’ formation during normal ageing and in early stages of Alzeheimer’s. In this study, we show neuronal shrinkage in the ERC appears to be a characteristic marker of Alzeheimer’s. We suspect this process is a function of ‘tau tangle’ formation in the affected cells, leading to poor memory abilities in older age. Identifying this contributing factor is crucial for early identification of Alzeheimer’s, monitoring its course and guiding treatment.’
Professor Gefen – who noted the study results are limited by its small sample size ‘partially due to SuperAgers being unique and rare’ and further research is needed– added: ‘One possibility for the greater size is that these neurons are protected from neurofibrillary tangles. We are not sure why these neurons were larger in SuperAgers or why they are relatively protected from disease.’
But the study authors noted this ‘protection’ comes ‘despite other age- related brain changes in SuperAgers– and concluded SuperAgers ‘carry a unique biological signature comprised of larger, healthier ERC neurons relatively devoid of tau tangles.’
