What defines you?

“You have this syndrome, but it is not going to define who you are…”

The story of this girl is incredible. She was born with a severe syndrome that, among other things, prevents the gain of weight. Despite all the obstacles and challenges she has faced during her entire life, she has become one of the most beautiful and encouraging persons I’ve ever heard. An extraordinary lesson of strength, love and gratitude.

How do you define yourself – Lizzie Velasquez

Effect of physical exercise on mental health

A beautiful article about the beneficial effects of physical exercise on physical and psychological health.

Photo by johnnyberg. License Creative Commons

4 beneficial effects of physical exercise on the brain

How sports can increase cognitive abilities and prevent depression.

Author: Agnese Mariotti

“It is well known that regular physical exercise (PE) improves health and longevity. Some of the best described effects consist in ameliorating cardiovascular functionality by decreasing resting heart rate and blood pressure, regulating energy and glucose metabolism, and reducing inflammation.

But PE –in particular endurance exercise– also directly influences brain function, resulting in improved brain health and consequently further enhancing general health.

Research in the last decade has identified some of the main effects of exercise on the brain and has started to unravel the molecular mechanisms by which the physiological changes triggered by exercise modify the activity of neurons in the brain.

1. Enhance cognitive abilities

PE enhances cognitive abilities: PE increases the number of functional neurons in the hippocampus, a brain region that is involved in learning and memory. In addition, it enhances synaptic plasticity, which improves signal transmission between neurons and the processing of information.

These effects are mediated by factors such as brain-derived neurotrophic factor (BDNF), insulin-like growth factor-1 (IGF-1) and vascular endothelial cell growth factor (VEGF), whose concentration in the hippocampus is increased by PE.

2. Prevent brain damage

PE protects the brain from stress and injury: PE induces the production of neurotrophic factors in several brain regions that limit damage to neurons, promote their survival, and assure their proper function. BDNF, IGF-1 and VEGF play an important role also in this process together with other molecules such as fibroblast growth factor-2 (FGF-2), nerve growth factor (NGF), glial cell-derived neurotrophic factor (GDNF), and antioxidant and DNA repair enzymes.

3. Fight Alzheimer’s and Parkinson’s

PE protects against neurodegenerative diseases: PE can counteract Alzheimer’s and Parkinson’s diseases by reducing the accumulation of misfolded and aggregated proteins that are characteristic of these pathologies, and by promoting their elimination. PE exerts these effects by stimulating the production in the brain of molecules that control protein folding and facilitate the degradation of damaged proteins, and of neurotrophic factors (in particular BDNF) and neurochemicals that improve neuron survival and functionality.

4. Prevent depression

PE prevents and alleviates depression: several studies have shown that PE can have therapeutic effects similar to those of anti-depressant drugs. The mechanisms by which PE decreases depression are complex and may include the regulation of the stress response through the hypothalamus, and the release of BDNF and serotonin that affect mood, appetite, and cognitive functions. Whatever the mechanism, everybody who regularly exercises is familiar with the uplifting effects of aerobic and endurance activities.

How?

But how does rhythmic and protracted muscle contraction, i.e. PE, produce its effects on the brain?

Changes in oxygen availability and consumption throughout the body induced by PE could contribute to the stimulation of brain activity. In addition, some still unidentified “exercise factor(s)” might be released from muscles during exercise, reach the brain and stimulate its functions.

In this respect a recent study published in Cell Metabolism showed that an “exercise factor” is responsible for the increased levels of BDNF in the hippocampus during exercise. Since BDNF is one of the main mediators of the beneficial effects of PE on the brain, the identification of the exercise factor that induces it is of great medical interest. In fact, this exercise factor or a similar molecule could in principle be administered to patients in order to boost BDNF production in the brain for the prevention and treatment of a large variety of diseases, from neurodegenerative disorders to learning disabilities and depression.”

References:

Wrann CD, White JP, Salogiannnis J, Laznik-Bogoslavski D, Wu J, Ma D, Lin JD, Greenberg ME, & Spiegelman BM (2013). Exercise Induces Hippocampal BDNF through a PGC-1α/FNDC5 Pathway. Cell metabolism, 18 (5), 649-59 PMID: 24120943

Mattson MP (2012). Energy intake and exercise as determinants of brain health and vulnerability to injury and disease. Cell metabolism, 16 (6), 706-22 PMID: 23168220

Cotman CW, Berchtold NC, & Christie LA (2007). Exercise builds brain health: key roles of growth factor cascades and inflammation. Trends in neurosciences, 30 (9), 464-72 PMID: 17765329

Sleep and brain detoxification

In this article Dr. Agnese Mariotti resumes the results of a recent research showing that sleep has an important detoxifying effect on our brain. This is an encouraging finding and supports the essential role that naturopathy (as well as other alternative medicines) gives to high quality sleep in order for the body to clear toxins from liquids and tissues, stay healthy and recharge itself during the night.

Boy and dog sleep_stock.xchngPhoto by joseas. Creative Commons license

Beauty sleep: giving our brain a detox

How sleeping flushes our brain clear of toxins.

Author: Agnese Mariotti

“We all need our regular beauty sleep, but how exactly does sleep produce its regenerative effects? Scientists have uncovered a mechanism by which sleep helps eliminate toxic substances from the brain and thus critically contributes to maintaining our good health.

As opposed to the brain, the body’s waste products are eliminated by the lymphatic system, a network of vessels that transfer metabolites from the tissues to the blood circulation and finally to the liver where they are degraded. The brain lacks lymphatic vessels and must rely on other mechanisms to get rid of toxins.

Nedergaard and colleagues of Rochester University recently discovered that the main detoxifying system in the brain consists of the cerebrospinal fluid (CSF) that is produced by filtration through the brain arteries into the surrounding spaces, and circulates among the brain structures.

Why we need a detox

The CSF moves by convective flow into the brain parenchyma and comes in contact with the interstitial fluid (ISF) present between cells in the so-called interstitial space, thus exchanging solutes with it. In particular, the CSF collects metabolites that were released in the ISF during brain activity, and transports them away from the brain to the venous blood circulation, for delivery to the liver.

There is evidence that in some neurodegenerative diseases and in brain injuries in which high amounts of “toxins” are produced, the CSF cannot efficiently clear the brain, which causes accumulation of toxins and further brain damage.

So, would it be possible to increase metabolites clearance from the ISF and improve our brain –and consequently general– health by enhancing CSF circulation? Nedergaard’s team has found that sleep does exactly this.

Flushing the brain

The scientists monitored CSF circulation in mice by injecting fluorescent dyes in the animals’ brains and followed their distribution using two-photon imaging. They found that a green dye administered to mice while sleeping diffused in the brain much more extensively than a red dye injected in the same mice after they were awaken.

The different dye distribution was the result of increased CSF influx and circulation into the brain of sleeping mice. This was caused by a significant increase (over 60%) in the volume of the interstitial space during sleep that led to decreased resistance to fluid movements and facilitated CSF flow.

As a consequence of increased CSF flow, toxic metabolites such as beta-amyloid, a protein degradation product that accumulates in the brain causing Alzheimer’s disease, were cleared much more efficiently from mice brains during sleep.

The scientists then demonstrated that sleep is accompanied by a decreased release in the brain of some neuromodulators, such as noradrenergic mediators, that sustain brain activity in the awake state. These neurotransmitters also regulate cell volume and specifically induce an increase in cell size during the awake state, which is followed by a reduction in the interstitial space.

Therefore sleep, by reducing the concentration of these neuromodulators decreases cell volume and increases the interstitial space, thus promoting CSF circulation and metabolite clearance.

Medical benefits

What are the implications of these findings? The study suggests that insufficient sleep —but also stress that increases the levels of noradrenergic transmitters— may contribute to neurodegenerative diseases by inducing a state of metabolic intoxication. We can thus envisage drugs that can mimic the effects of sleep at the molecular level and improve CSF circulation and metabolite elimination.

In addition, preclinical studies have shown that it’s possible to monitor CSF circulation in animals by Magnetic Resonance Imaging. This analysis applied to human patients could help diagnose neurodegenerative diseases at their initial stages when the CSF flux may already be reduced, and promptly administer therapies.

In conclusion, this study is the first demonstration of the detoxifying function of sleep and suggests that we really need to spend about a third of our lives sleeping in order to live healthily the other two thirds.”

Reference

Xie L, Kang H, Xu Q, Chen MJ, Liao Y, Thiyagarajan M, O’Donnell J, Christensen DJ, Nicholson C, Iliff JJ, Takano T, Deane R, & Nedergaard M (2013). Sleep drives metabolite clearance from the adult brain. Science (New York, N.Y.), 342 (6156), 373-7 PMID: 24136970.

Meditation to quit smoking

The positive effect of meditation on our physical and mental health is becoming more and more evident and accepted even by the scientific community. This article resumes recent findings showing how a meditation technique called Integrative Body-Mind Training (IBMT) can help people to quit smoking in a very rapid, efficient and non-invasive way.

waterlilies_stock.xchng_MEJonesPhoto by MEJones. Creative Commons license

How to quit smoking: meditation and its effects on self-control

This technique produces the desired effects in only a few hours of practice.

Author: Agnese Mariotti

“Integrative Body-Mind Training (IBMT) is a meditation technique that in randomized controlled studies proved to be effective in reducing stress and improving self-control, attention, and social behavior. This technique works rapidly, producing the desired effects in only a few hours of practice during one or two weeks, differently from other meditation methods that require much longer times – even years – to achieve results.

Interestingly, the effects of IBMT are accompanied by changes in the activity of specific brain areas, an observation that provides potential scientific support and explanation to its effects.

As described by its developer, Yi-Yuang Tang, director of Texas Tech Neuroimaging Institute, IBMT aims to achieve a state of restful alertness and an attitude of openness to experiences, which lead to high self-awareness as well as to awareness of, and balance with the environment.

IBMT does not focus directly on thought control, which poses a difficult challenge in particular in stressed individuals, but nonetheless achieves it through a variety of techniques including body relaxation and mental imagery, practiced in the presence of a guiding instructor.

In a study published in PNAS, Y.-Y. Tang and colleagues report that IBMT reduces smoke consumption.

The scientists recruited people interested in stress reduction and treated them according to two techniques, IBMT or Relaxation Training (RT).

RT involves different methods of relaxation compared to IBMT, like for example concentration on specific muscles, and on feelings such as those of localized warmth and relaxation.

The IBMT and RT groups included 33 and 27 people respectively, of which 15 smokers in the IBMT group and 12 smokers in the RT one, each reporting an average consumption of 10 cigarettes per day.

The two groups underwent treatment for a total of 5 hours during two weeks. At the end of the trial, stress was significantly reduced in both groups, indicating that both techniques were successful in their main goal. In addition, IBMT also reduced smoking of 60%, while RT had no effect on it.

The scientists also found that IBMT effects were accompanied by changes in brain activity, with increased activity in the prefrontal cortex (PFC), and decreased activity in the cerebellum and in the posterior cingulate cortex. Interestingly, PFC is an area known to regulate self-control and addiction, whose activity was previously shown to be low in smokers.

No such changes were measured in the RT group.

The authors also report that the effects of IBMT on smoke reduction seem to last at least for a few weeks after the end of the treatment. In addition, they do not seem to depend on the intention of quitting smoke: in fact also participants who reported no intention of quitting reduced their tobacco use, suggesting that IBMT may act on unconscious processes.

The researchers conclude that by improving self-control through the stimulation of specific brain regions, IBMT may help not only to reduce smoking but importantly also to cure stress-related and mental conditions, as well as addiction problems in general, including drug addiction and abuse.

Definitely further studies are necessary to validate the preventive and therapeutic effects of IBMT. If confirmed, the next challenge will be the acceptance by the medical and scientific community of this non-invasive, low-cost technique, at odds with western medicine practices.”

References

Tang YY, Tang R, & Posner MI (2013). Brief meditation training induces smoking reduction. Proceedings of the National Academy of Sciences of the United States of America, 110 (34), 13971-5 PMID: 23918376.

Y.-Y. Tang, Y. Ma, J. Wang, Y. Fan, S. Feng, Q. Lu, Q. Yu, D. Sui, M. Rothbart, M. Fang, and M. Posner (2013). Short-term meditation training improves attention and self-regulation. Proc. Natl. Acad. Sci. USA.

Y.-Y. Tang, Q. Lu, X. Geng, E.A. Stein, Y. Yang, and M. Posner (2010). Short-term meditation induces white matter changes in the anterior cingulated. Proc. Natl. Acad. Sci. USA, 107: 15649 (2010).

A subversive plot

A subversive plot: how to grow a revolution in your own backyard

Video by Roger Doiron

Roger Doiron is founding director of Kitchen Gardeners International, a network of people taking a hands-on approach to re-localizing the global food supply. Doiron is an advocate for new policies, technologies, investments, and fresh thinking about the role of gardens. His successful petition to replant a kitchen garden at the White House attracted broad international recognition. He is also a writer, photographer, and public speaker.”