Research in animal models shows physical exercise can induce changes in the brain. In humans, studies also revealed changes in brain physiology and function resulting from physical exercise, including increased hippocampal and cognitive performance (1). Several studies in mice and rats also demonstrated that exercise can improve learning and memory and decrease neuroinflammation in models of Alzheimer’s disease and other neurodegenerative pathologies (2); these benefits are tied to increased plasticity and decreased inflammation in the hippocampus in mice (2). If regular time pounding the pavement does improve brain function, what is the underlying molecular biology of exercise-induced neuroprotection? Can we identify the cellular pathways and components involved? Can we detect important components in blood plasma? And, is the benefit of these components transferrable between organisms? De Miguel and colleagues set out to answer these questions and describe their results in a recent study published in Nature.
Continue reading “Run to Remember: A Mouse-Model Study Investigating the Mechanism of Exercise-Induced Neuroprotection”alzheimer disease
A Clean Brain Is a Healthy Brain
It is hard to undermine the role of cleanliness in disease prevention, both internally and externally. Within our body, the lymphatic system plays an important role in clearing the intercellular passages of large and potentially harmful toxic molecules and recirculate back into the blood stream. This enables the transport of these molecules to liver for inactivation and subsequent removal from the body. Therefore, lymphatic system prevents build-up of soluble proteins in the interstitial space. Typically, more metabolically active a cell is, more intricate is the lymphatic vasculature around it. This observation was in contrast to our scientific knowledge a few years ago, when we believed that due to the presence of the blood-brain barrier, there was no lymphatic system active in the brain. The brain, as we know, is highly active metabolically and the removal of harmful solutes and proteins from the neuronal vicinity is of utmost urgency. For a long time it was believed that cerebrospinal fluid (CSF), while coursing through the brain also removed cellular metabolite by products, apart from carrying nutrients to brain tissue, through a process known as diffusion. This is a rather slow process and it did not very well explain how large molecules such as proteins were removed from the interstitial place.
Recently, using two-photon imaging technique in live mice, scientists at Rochester discovered (1) that there is another vasculature functioning in the brain which circulates CSF to every corner of the brain much more efficiently, through bulk flow or convection. Continue reading “A Clean Brain Is a Healthy Brain”