Representing a key mechanism that underlies memory loss in Alzheimer’s disease (AD) and related tauopathies. Here, we found that reduced levels of the memory-associated protein KIdney/BRAin (KIBRA) in the brain and increased KIBRA protein levels in cerebrospinal fluid are associated with cognitive impairment and pathological tau levels in disease. We next defined a mechanism for plasticity repair in vulnerable neurons using the C-terminus of the KIBRA protein (CT-KIBRA). We showed that CT-KIBRA restored plasticity and memory in transgenic mice expressing pathogenic human tau; however, CT-KIBRA did not alter tau levels or prevent tau-induced synapse loss. Instead, we found that CT-KIBRA stabilized the protein kinase Mζ (PKMζ) to maintain synaptic plasticity and memory despite tau-mediated pathogenesis. Thus, our results distinguished KIBRA both as a biomarker of synapse dysfunction and as the foundation for a synapse repair mechanism to reverse cognitive impairment in tauopathy.

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¹Buck Institute for Research on Aging, Novato, California, USA.

²Memory and Aging Center, Department of Neurology, University of California San Francisco, San Francisco, California, USA.

³Gladstone Institutes, San Francisco, Califoria, USA.

⁴Weill Institute for Neurosciences, Department of Pathology, University of California San Francisco, San Francisco, California, USA.

In recent years, some scientists and advocates have warned that playing contact sports like football and hockey may increase the risk of brain diseases like Alzheimer’s disease or chronic traumatic encephalopathy (CTE) due to a buildup of a specific protein in the brain.

But a new Northwestern Medicine study of 174 donated brains, including some from former high school and college football players, pumps the brakes on that theory.

“The long and short of it is no, this protein in this specific brain region is not increased in people who played football at the amateur level. It throws a little bit of cold water on the current CTE narrative,” said corresponding author Dr. Rudolph Castellani, professor of pathology at Northwestern University Feinberg School of Medicine and a Northwestern Medicine neuropathologist.

For decades, the story of Alzheimer’s research has been dominated by a battle between A-beta and tau amyloids, both of which can kill neurons and impact the brain’s ability to function. A new study suggests, however, that these sticky brain plaques may not be operating alone.

Johns Hopkins University researchers have identified more than 200 types of misfolded proteins in rats that could be associated with age-related cognitive decline.

The findings could lead the way to finding new therapeutic targets and treatments in humans that could provide relief for the millions of people over 65 who suffer from Alzheimer’s, dementia, or other diseases that rob them of their memories and independence as they age.

By Bruce Goldman

A blood-test analysis developed at Stanford Medicine can determine the “biological ages” of 11 separate organ systems in individuals’ bodies and predict the health consequences.