Move for Brain Health » BIOME ONBOARD AWARENESS: THE SCIENCE BEHIND FOOD, OUR MICROBIOME, AND DISEASE

Last Updated on January 13, 2019 by Patricia Carter

SUMMARY: You can’t outrun a bad diet, but that said, you must still move for brain health! This post shares a study that published last week, [Choi et al 2018], that found that the brain cognition benefit of exercise (that would be new neuron production (aka neurogenesis) AND increased production of brain derived neurotropic factor (BDNE)) could NOT be achieved by drugs alone because those newly produced neurons could not survive in the inflamed Alzheimer’s Disease (AD) brain tissue. However, it was achieved in a mice AD model by combining drugs and gene therapy to simultaneously turn on neurogenesis and BDNF production, but there is NOT YET a way to safely achieve the same effect in humans using drugs and gene therapy. The Pearl: Induce both new neuron neurogenesis and BDNF via exercise in order to let the newly produced neurons survive and thrive! Specifically, for brain health, Joyce Gomes-Osman’s study looked at almost 100 existing studies associating exercise with 122 different tests for brain function, having data for over 11,000 older people. [Gomes-Osman et al 2018] found ⇒ Exercise one hour, three times a week using a diverse regimen that includes aerobic exercise, resistance training, AND mind-body exercises like tai-chi because all are associated with evidence specifically supporting benefits for brain health in both people without cognitive decline as well as those with mild cognitive impairment or dementia. ♥♥♥ Go move! ♥♥♥ Exercise ⇒⇒ New Neurons +++ BDNF ⇒⇒ IMPROVES Cognition! Additionally, another important reference for appreciation of other factors beyond movement impacting cognition and AD, is: Alzheimer’s Dementia Bredesen Approach.

Alzheimer’s disease (AD) pathology (simplified):

Destroys neurons and synapses in the brain, leading to dementia.
New neurons can be produced throughout life in the hippocampus through a process called adult hippocampal neurogenesis (AHN). BUT, newly produced neurons from drugs cannot survive in the regions affected by AD, one main reason is because of the neuroinflammation present. [Choi et al 2018]

What mice are teaching us: MOVE for Brain Health

⇒⇒⇒ EXERCISE is still one of the BEST ways to turn on the production of new brain neurons (aka neurogenesis) in the area of brain where memories are encoded AND it increases BDNF which lets them survive & thrive, and that improves cognition.

[Choi et al 2018], found that in an AD mice model:

Exercise-induced AHN improved cognition function in all three types of memory tests, reduced Aß load, and increased levels of hippocampal BDNF, PSD95, SYP, IL-6, FNDC5, and synaptic markers.
Increasing AHN ALONE (without exercise) does not ameliorate cognitive function and did not change Aß plague levels. Increasing AHN alone was sufficient to improve pattern separation memory in male AD mice but not in female mice; however, it was not sufficient to improve other forms of cognition. Areas tested included: A delayed nonmatching to place (DNMP) task to measure spatial pattern separation, an eight-arm radial arm maze (RAM) to measure reference and retention memory, and a Y-maze to measure spatial working memory. Pattern separation, which is the formation of distinct representations of similar inputs, has been shown to require adult-generated neurons (16). Reduced ability to separate patterns (i.e., to recognize differences between very similar events) is one of the first behavioral deficits in patients with mild cognitive impairments, which often progress to AD (17).
AHN activation was required for exercise-induced improvement in memory. “Exercise alone, in the absence of increased AHN, exerted no observed beneficial effects on cognitive function.” The neurons induced by exercise differed because exercise ALSO turned on production of brain derived neurotropic factor (BDNE). BDNE creates a less inflammatory brain environment.
This suggests that promoting AHN can ameliorate AD pathology and cognitive deficits but only in the presence of a healthier, improved local brain environment, e.g., stimulated by physical exercise. Physical exercise “cleans up” the inflammation permitting the new neurons induced by exercise to survive and thrive, and that improved cognition.

Favorite quotes from Rudolph Tanzi, senior author [McGreevey, 2018]:

“It is not enough just to turn on the birth of new nerve cells; you must simultaneously ‘clean up’ the neighborhood in which they are being born …. Exercise can achieve that.”

and…

“Although exercise-induced AHN (adult hippocampal neurogenesis) improved cognition in Alzheimer’s mice by turning on neurogenesis, trying to achieve that result by using gene therapy and drugs did not help.”

The researchers were able to combine drugs and gene therapy that together mimicked induction of neurogenesis AND increased BDNF production in the mice AD models (that is what happens with exercise) positively effecting cognitive function. BUT… There is not yet a way to safely achieve the same effects using drugs and gene therapy in humans.

What is the ideal exercise for brain health and HOW much?

Joyce Gomes-Osman, an assistant professor in physical therapy and neurology at University of Miami Miller School of Medicine looked at almost 100 existing studies associating exercise with 122 different tests for brain function. The data included over 11,000 older people. Their study published in the journal Neurology: Clinical Practice, and is named [Gomes-Osman et al 2018] Exercise for Cognitive Health in Aging, A Systematic Review for an Evaluation of Dose. The study found:

- Exercise one hour, three times a week, using a diverse regimen that includes aerobic exercise, resistance training, AND mind-body exercises like tai-chi because all are associated with evidence specifically supporting benefits for brain health.

The effect applied to both people without cognitive decline as well as those with mild cognitive impairment or dementia.
Read more at [Gomes-Osman, 2018, Harvard Health Publishing, Harvard Medical School].

This contrasts sharply to how America really moves. The National Institute of Health Statistics reports that less than 20% do any type of exercise each week, and less than 40% of adults 65 years and older do at least 150 minutes of exercise per week. [Ward et al 2016] Note: This is the target of 30 minutes of exercise, five days a week for physical health ⇒ But this isn’t necessarily what is required for brain health).

Details: The ideal exercise for brain health

Key excerpts from [Gomes-Osman, 2018, Harvard Health Publishing, Harvard Medical School] are:

The verdict is still out on an ideal exercise “dose” for brain health… we are still learning about all the ways in which exercise changes our biology, since not all exercise is created equal, and of course it ultimately depends on who we are, for we are all different. The best exercise program for one person may be quite different from the best one for another.
Humans and animal studies have linked cognitive improvements following exercise (mainly aerobic, such as running and cycling) to the increased capacity of the heart, lungs, and blood to transport oxygen. As a result, generalized brain effects, such as a boost in the number of blood vessels and synapses, increasing brain volume, and decreasing age-related brain atrophy, have all been reported.
Aside from this, more localized effects in brain areas related to thinking and problem solving have also been reported, such as a boost in the number of new nerve cells and increases in proteins that help these neurons survive and thrive.
In recent years cognitive improvements have also been demonstrated with other forms of exercise, such as low-intensity mind-body exercises (think some forms of yoga and tai chi) and resistance (i.e., weight) training. Because these exercises either do not work the heart as hard, or do so in a different way, we know less about exactly how they promote these cognitive changes.
However, I see this as an encouraging finding for two reasons. First, some sedentary people may need to start with a more gentle routine, eventually building up to more vigorous exercise practices; and second, many people already engage in resistance training for other reasons, such as building stronger muscles and bones.

[Wendy Suzuki, neuroscientist, TedWomen 2017], teaches that “exercise is the most transformative thing that you can do for your brain.” Aerobics improves cognition by changing up the hippocampus and prefrontal cortex, and increases neurotransmitters:

1. A single workout has immediate transient effects on your brain that increases levels of neurotransmitters like dopamine, serotonin and noradrenaline. These increase your mood right after the workout, improves your ability to shift and focus attention which lasts for at least two hours, and i t will improve your reaction times.

1. For long term effects, you must change your exercise regime to increase your cardio respiratory function. This is because exercise actually changes the brain’s anatomy, physiology and function. Exercise actually produces brand new brain cells, new brain cells in the hippocampus, that actually increase its volume, as well as improve your long-term memory.

1. Long-term exercise improves improves attention function dependent on your prefrontal cortex. You get better focus and attention, AND the volume of the hippocampus increases. The immediate effects of improved mood with exercise lasts for a long time because you get long-lasting increases in the good mood neurotransmitters (dopamine, serotonin, and noradrenaline).

Exercise protects the brain by making the hippocampus and prefrontal cortex bigger and stronger. These two areas are most susceptible to neurodegenerative diseases and normal cognitive declines in aging. So, with increased exercise over your lifetime, you’re not going to cure dementia or Alzheimer’s disease, but what you’re going to do is you’re going to create the strongest, biggest hippocampus and prefrontal cortex so it takes longer for these diseases to actually have an effect.

Details: How Long do You NEED to Exercise?

Key excerpts from [Park, 2018, TIME.com] are:

People who exercised about 52 hours over a period of about six months showed the biggest improvements in various thinking and speed tests. On average, people exercised for about an hour, three times a week. And the effect applied to both people without cognitive decline as well as those with mild cognitive impairment or dementia.
People in the study showed the strongest improvements in their ability to solve problems and process information. The effect was not as robust in memory tests, but Gomes-Osman notes that most complex brain functions, from reasoning and processing speed to recall, are related. “There is an overlap between being able to manage time, pay attention and [do] memory tasks,” she says.
What surprised the researchers was that the only strong correlation between exercise and brain function occurred when they looked at the OVERALL time people spent being physically active. They did not find associations between improvements in thinking and the frequency, intensity or length of time people exercised. “I had a mindset [going into the study] that the weekly minutes spent exercising was definitely something that was helpful, since we know that is important for the guidelines for physical health by the Centers for Disease Control and the American Heart Association,” says Gomes-Osman. “But I was surprised to see that it wasn’t.”
That may further support the idea that for brain health, the overall and cumulative effect of physical activity is what’s important. This suggests that exercise affects the brain in a variety of different ways, from preserving the brain’s nerve network that starts to decline with age, to boosting the function of neurons and improving blood flow to brain cells, as well as promoting the production of growth factors to help cells involved in higher level thinking tasks.
“These results help us get a little closer to very practical advice,” says Gomes-Osman. The current study included different types of exercise: aerobic (which is backed by the most research on its relationship to the brain), weight training and mind-body activities like tai chi. She hopes to learn more about what types of exercise seem to have the most benefit for the brain, as well as how that movement should be distributed in minutes, hours and days. That information could one day help people be more proactive about avoiding cognitive decline, and may even help to stave off some of the brain problems associated with more severe degenerative diseases like dementia and Alzheimer’s.

[Wendy Suzuki, neuroscientist, TedWomen 2017] teaches: You don’t have to become a triathlete to get exercise induced brain cognition benefit. The rule of thumb is get three to four times a week aerobic exercise, a minimum of 30 minutes an exercise session, and you want to get your heart rate up. You don’t have to go to the gym. Just a dd an extra walk around the block in your power walk, take stairs, a nd power-vacuuming can be as good as the aerobics class taken at the gym.

In conclusion:

⇒ EXERCISE is still one of the best ways to turn on the production of new brain neurons (aka neurogenesis) in the area of brain where memories are encoded AND it increases BDNF which lets them survive AND thrive, and that improves cognition.

⇒ Exercise one hour, three times a week, using a diverse regimen that includes aerobic exercise, resistance training, AND mind-body exercises like tai-chi because all are associated with evidence specifically supporting benefits for brain health. The effect applied to both people without cognitive decline as well as those with mild cognitive impairment or dementia.