Physical activity is very important for a variety of reasons, including helping to protect the structure and function of the brain as we age. This may be the key to reducing the risk of developing certain neurodegenerative conditions such as Alzheimer’s disease.
Researchers have long known about the protective effects of exercise, but it remains a mystery why it has this effect on the brain. However, recent research published in the Journal of Neuroscience may shed some light on this puzzle.
According to the findings, physical activity alters the activity of immune cells in the brain, which reduces inflammation in the brain.
The brain contains a special class of immune cells called microglia that constantly investigate damage and infections in brain tissue and remove debris and dying cells.
Microglia also help direct the production of new neurons, nerve cells in the brain that communicate with other cells and send messages, through a process called neurogenesis that involves learning and memory.
However, in order for microglia to step up and work, they need to switch from dormant to active. Signals from pathogens (such as viruses) or damaged cells activate microglia. This changes the shape and produces pro-inflammatory molecules. This allows you to resolve and repair damage and infections.
However, microglia are improperly activated with age, causing chronic brain inflammation and potentially impairing neurogenesis. This inflammation has been suggested as a reason why brain function often declines with age, and these changes can be exacerbated in neurodegenerative conditions such as Alzheimer’s disease.
Studies in laboratory mice and rats have shown that exercise can counteract some of the harmful effects of microglial activation. However, this latest study reveals for the first time a link between physical activity, decreased microglial activation, and better cognitive function in the human brain.
The researchers in this study examined 167 men and women who participated in the Rush Memory and Aging project. This is a long-term project at Rush University in Chicago, aimed at identifying factors that contribute to the brain health of the elderly. Participants completed an annual assessment of physical activity monitored by a wearable activity tracker, as well as an assessment of cognitive function and athletic performance (such as strength and walking speed).
Participants also donated their brains for postmortem analysis as part of their research. This allows researchers to analyze brain tissue for evidence of activated microglia and signs of brain disease such as the presence of unhealthy blood vessels and plaques containing the protein beta-amyloid (a characteristic of Alzheimer’s disease). I did.
The researchers also focused on the levels of synaptic proteins in the participants’ brains. Since synapses are small junctions between nerve cells through which information is transmitted, these levels provide a wide range of indicators of healthy brain function.
Participants were on average 86 years old when physical activity began to be monitored and about 90 years old when they died. About one-third of the participants had no cognitive impairment, one-third had mild cognitive impairment, and one-third were diagnosed with dementia.
However, postmortem analysis revealed that about 60% of participants actually have signs of Alzheimer’s disease (such as amyloid plaques) in their brains. This indicates that the presence of typical signs of Alzheimer’s disease does not necessarily mean that they present the major symptoms of cognitive impairment during their lifetime.
Not surprisingly, the younger the participants, the more physically active and improved their motor function. Overall, more physical activity is associated with reduced microglial activation in certain brain regions normally affected early in the onset of Alzheimer’s disease, such as the inferior temporal gyrus involved in memory and recall. was doing.
This was true even when there were signs of Alzheimer’s disease in the brain. This suggests that physical activity can reduce the harmful effects of inflammation in the brain, even if the disease has already begun to develop. This study also showed that activation of more microglia was associated with greater cognitive decline and lower synaptic protein levels.
These findings indicate that inflammation of the brain can have a profound effect on cognitive function and may be a risk factor for developing Alzheimer’s disease, as well as physical activity. It also shows that it may help develop the resilience of the brain against potentially damaging effects.
While these findings are promising, there are some limitations to the study. Postmortem analysis reveals only one snapshot at the time of brain condition. This means that it is not possible to know exactly when the signs of illness occurred in the participants’ brains and when their physical activity made a difference.
Also, this study was an observation only. That is, changes in the lives of participants were observed, as opposed to intervention studies in which different people were randomly assigned to exercise participants and non-exercise groups.
Therefore, it cannot be reliably concluded that physical activity directly caused the observed changes in brain tissue and cognitive function. These findings also do not explain the mechanism by which exercise induces these effects.
However, this study weighs on increasing evidence that physical activity can protect brain health and function. Working throughout our lives gives us the best chances of preventing the development of Alzheimer’s disease and other neurodegenerative conditions and may help us lead a long, healthy and independent life.
The author is a professor of physiology at Trinity College Dublin.This article is syndicated by PTI conversation.
Exercise may help reduce inflammation in the brain and protect us from illness, Health News, ET HealthWorld
Source link Exercise may help reduce inflammation in the brain and protect us from illness, Health News, ET HealthWorld