It is known that one of the earliest sites of Alzheimer’s disease pathology is the hippocampus, a brain structure critical for the learning and memory processes that falter early in Alzheimer’s disease. The apoE4 gene creates a protein of the same name that markedly increases a person’s risk for Alzheimer’s disease and occurs in 65%-80% of people with Alzheimer’s disease. ApoE4 protein is the major genetic risk factor for Alzheimer’s disease, however, the mechanism by which it causes cognitive decline and disrupts hippocampal memory processes is unclear. Now, a study from researchers at the Gladstone Institutes shows that the apoE4 protein changes the activity of neurons in the hippocampus. The team state that in this region, apoE4 decreases two types of brain activity that are important for memory formation, namely, sharp wave ripples and coincident slow gamma activity. The opensource study is published in the journal Neuron.
The current study tested mice that expressed apoE4 in all cells except inhibitory neurons in the hippocampus. From earlier research, the scientists knew that these mice showed no signs of inhibitory neuron death in the hippocampus, and their ability to learn and form memories was not impaired. Results show that the mice exhibited normal slow gamma activity despite having fewer ripples. Data findings show that slow gamma activity, the coordination of cell firing during playback, appears to be a critical factor in memory consolidation, rather than the number of replay events from the ripples.
The team surmise that their findings suggest disrupted slow gamma activity during ripples is a major consequence of apoE4 expression that likely impairs memory consolidation. For the future, the researchers state that with this knowledge, the global medical community can now work toward correcting or restoring slow gamma activity in the hippocampus to prevent or alleviate memory loss in Alzheimer’s disease.
Source: Gladstone Institutes
Michelle Petersen is the founder of Healthinnovations, having worked in the health and science industry for over 21 years, which includes tenure within the NHS and Oxford University. Healthinnovations is a publication that has reported on, influenced, and researched current and future innovations in health for the past decade.
Michelle has been picked up as an expert writer for Informa publisher’s Clinical Trials community, as well as being listed as a blog source by the world’s leading medical journals, including the acclaimed Nature-Springer journal series.
Healthinnovations is currently indexed by the trusted Altmetric and PlumX metrics systems, respectively, as a blog source for published research globally. Healthinnovations is also featured in the world-renowned BioPortfolio, BioPortfolio.com, the life science, pharmaceutical and healthcare portal.
Most recently the Texas A&M University covered The Top 10 Healthinnovations series on their site with distinguished Professor Stephen Maren calling the inclusion of himself and his team on the list a reflection of “the hard work and dedication of my students and trainees”.
Michelle Petersen’s copy was used in the highly successful marketing campaign for the mega-hit film ‘Jumanji: The Next Level, starring Jack Black, Karen Gilian, Kevin Hart and Dwayne ‘The Rock’ Johnson. Michelle Petersen’s copywriting was part of the film’s coverage by the Republic TV network. Republic TV is the most-watched English language TV channel in India since its inception in 2017.
An avid campaigner in the fight against child sex abuse and trafficking, Michelle is a passionate humanist striving for a better quality of life for all humans by helping to provide traction for new technologies and techniques within healthcare.