According to a recent study by a team of researchers in Massachusetts, the process of producing new neurons (otherwise known as neurogenesis) in the specific areas of the brain where memories are stored – namely the hippocampus and striatum – can improve cognitive function in Alzheimer’s patients, at least as proven in the mouse models used as substitutes for human Alzheimer’s patients. The study shows how inflammation present in the brains of Alzheimer’s disease patients blocks cognition, and that physical exercise plays a role in ‘cleaning up’ those areas so that new neurons can survive.
The mice models indicate that exercise is one of the better ways to induce neurogenesis, which reduces the symptoms of Alzheimer’s disease as it improves cognition.
The researchers attempted to replicate the positive impact of neurogenesis, but instead of inducing new neurons via exercise, they opted for gene therapy and drug treatment. These experiments demonstrated that neurogenesis could indeed be induced through gene therapy and specific drugs designed to promote progenitor neural cells; however, the cognitive benefits were markedly limited compared to those benefits achieved through exercise. The reason: new neurons induced by drugs and/or gene therapy weren’t able to survive in the brain regions affected by the neuroinflammation caused by Alzheimer’s pathology.
So, how does exercise differ compared to gene therapy and drugs? Exercise also induces the production of BDNF (otherwise known as brain-derived neurotrophic factor). BDNF is essential for the growth and survival of brain neurons as it creates a more hospitable environment for the cells to thrive in. In a nutshell, gene and drug therapy induces the production of new neurons but doesn’t alter the environment in which the neurons can survive, whereas exercise induces neurogenesis and modifies the neurons’ environment. Exercise ‘cleans up’ the neighborhood in which the neurons are born, paving the way for their survival.
The benefits of exercise, the perfect companion to healthy eating, goes well beyond physical vanity; exercise also improves brain function and cognition.