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"Exercise is the only way to preserve muscle function"-
Exercise/Brain/Bone/Muscle Connection
 
 
  Gerard Karsenty, M.D., Ph.D
 
Bone - Muscle - Brain -Exercise Connection - Does Exercise & Muscle Strength in Legs Affect Brain Function?.....HEALTHY BONE DELAYS Aging in Multiple Organs
 
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At the Comorbidities & Adverse Events Workshop in NYC last week Gerard Kersanty presented a slide talk discussing his research on this question & the slides are below - "Regulation of muscle function and mass by the bone-derived hormone osteocalcin"

there appears to me Jules Levin that there is a connection between muscles - leg muscles - and brain/cognitive function - thus a connection with aging both the mental & physical aspects.
 
Full text of publication in next email, has been posted on NATAP website
 
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Powerful hormone jab could get elderly exercising 'like they were years younger'....http://www.mirror.co.uk/news/uk-news/powerful-hormone-jab-could-elderly-8190357
 
"This may be one way to treat age-related decline in muscle function in humans."......studyfound the hormone helps muscle fibres uptake and catabolize glucose and fatty acids as nutrients during exercise
 
"Osteocalcin is not the only hormone responsible for adaptation to exercise in mice and humans, but it is the only known bone-derived hormone that increases exercise capacity.
 
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Improve Muscle Function: Osteocalcin

 
As we age, cognitive decline is a problem that many of us face. Though pharmacological interventions do not currently exist to help fix this issue, exercise has been shown to improve the way our brains function and therefore how we think and feel. However, an inherent problem to the "just exercise" solution is that as we age, our capacity for exercise declines. What if something existed that increased our ability to exercise as we age? Scientists have recently begun to explore this exciting topic.
 
During exercise, our muscles become activated and need glucose and fatty acids to function properly. However, until recently, it was unknown what exactly drives optimal muscle utilization. Mera and colleagues at the Department of Genetics and Development at Columbia University Medical Center sought to uncover the molecular mechanisms underlying this process (Mera et al., 2016). Interestingly, they turned to the skeletal system. In their paper, they state that "the ability of bone to sense mechanical forces, the physical proximity of the two tissues, and the fact that exercise capacity and bone mass decline at the same time have long suggested that a crosstalk between bone and muscle may exist." As it was recently discovered that certain hormones are directly secreted from the bones, they turned to one in particular that is involved in metabolism and bone building: osteocalcin (Karsenty & Olsen, 2016).
 
Related Article:Exercise as a Stimulus for Bone Health
 
First, they found that circulating osteocalcin levels doubled after only one 45-minute exercise session in both young adult mice and men. Second, they found that during the aging process, osteocalcin levels in mice decreased by 70%, which was accompanied by a decreased ability to perform exercise. Further, they found that aging dampened the ability of exercise to increase circulating osteocalcin. Similar findings were found in monkeys and humans as well, indicating that this is a robust finding across species. Based on these findings, they next asked whether exogenously administered osteocalcin could increase the capacity for exercise in young adult mice. What do you think happened? By injecting mice with osteocalcin immediately before exercise, their capacity to exercise significantly increased. That is, compared to controls, mice injected with osteocalcin increased their time spent running and distance traveled on a treadmill by over 20% before they reached exhaustion. These exciting findings led them to ask the same question in older mice with an already decreased capacity for exercise. What happened when older mice were injected with osteocalcin? They were able to run just as much as young mice, essentially "reversing the age-induced decrease in exercise capacity."
 
They then used a genetic mouse model to determine that osteocalcin works to enhance exercise capacity by first being secreted by bone and then binding to receptors located on the muscle. This process of osteocalcin binding to the muscle causes a cascade of events to occur. First, osteocalcin breaks down stored glycogen into glucose, which the muscles use as an energy source during exercise. Second, osteocalcin promotes the uptake of both glucose and fatty acids, which the muscles also use as a source of energy. Collectively, these things cause activation of the Krebs cycle (think back to high school biology), which produces ATP (adenosine triphosphate) as its end product. ATP is referred to as the cell's "energy currency", and is required to increase muscle function.
 
Related Article:Brain Growth with Exercise
 
The authors point out that, "These findings do not exclude in any way the likely possibility that other molecules may contribute to the regulation of adaptation to exercise." However, it is exciting to begin to understand how exercise promotes muscular function. Even more exciting is the identification of molecular factors that can enhance muscle function as we age. Future research will be needed to determine whether osteocalcin supplementation can be used in aging humans to promote exercise capacity. Interestingly, a very recent study linked plasma osteocalcin levels to brain functioning in humans (Bradburn et al., 2016). This possible link between bone health and brain health warrants future research and is another exciting example of the brain body connection.
 
References:
 
Bradburn, S., McPhee, J. S., Bagley, L., Sipila, S., Stenroth, L., Narici, M. V., ... & Meskers, C. G. (2016). Association between osteocalcin and cognitive performance in healthy older adults.Age and Ageing.
 
Karsenty, G., & Olson, E. N. (2016). Bone and Muscle Endocrine Functions: Unexpected Paradigms of Inter-organ Communication.Cell,164(6), 1248-1256. Mera, P., Laue, K., Ferron, M., Confavreux, C., Wei, J., Galan-Diez, M., ... & Bacchetta, J. (2016). Osteocalcin signaling in myofibers is necessary and sufficient for optimum adaptation to exercise.Cell Metabolism,23(6), 1078-1092.
 
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Bone hormone boosts performance of ageing muscles: study
 
http://www.deccanchronicle.com/lifestyle/health-and-wellbeing/160616/bone-hormone-boosts-performance-of-ageing-muscles-study.html
 
"It was extremely surprising that a single injection of osteocalcin in a 12-month-old mouse could completely restore its muscle function to that of a 3-month-old mouse," said Karsenty......"Osteocalcin is not the only hormone responsible for adaptation to exercise in mice and humans, but it is the only known bone-derived hormone that increases exercise capacity.

You tube Talk by Dr Karsenty:
https://www.youtube.com/watch?v=3bDwBRM2GKE

The study describes the first bone-derived hormone known to affect exercise capacity.

The study was published in the journal Cell Metabolism. (Photo: Youtube/ Screen grab) Washington: Injecting a bone hormone, that is produced during exercise, can help rejuvenate ageing muscles and increase the capacity of performing physical activities, a new study has found.
 
When we exercise, our bones produce a hormone called osteocalcin that increases muscle performance, researchers have found. Osteocalcin naturally declines in humans as we age, beginning in women at age 30 and in men at age 50.
 
The study describes the first bone-derived hormone known to affect exercise capacity and shows that injecting it can reverse the age-related exercise capacity decline in mice. "Our bones are making a hormone called osteocalcin that provides an explanation for why we can exercise," said Gerard Karsenty, from the Columbia University Medical Centre "The hormone is powerful enough to reconstitute, in older animals, the muscle function of young animals," said Karsenty.
 
During exercise in mice and humans, the levels of osteocalcin in the blood increase depending on how old the organism is.
 
The researchers observed that in 3-month-old adult mice, osteocalcin levels spiked approximately four times the amount that the levels in 12-month-old mice did when the rodents ran for 40 minutes on a treadmill.
 
The three-month-old mice could run for about 1,200 metres before becoming exhausted, while the 12-month-old mice could only run half of that distance.
 
To study whether osteocalcin levels were affecting exercise performance, researchers tested mice geneticallyengineered so the hormone could not signal properly in their muscles.
 
Without osteocalcin muscle signalling, the mice ran 20-30 per cent less time and distance than their healthy counterparts before reaching exhaustion.
 
When healthy mice that were 12 and 15 months old - whoseosteocalcin levels had naturally decreased with age - were injected with osteocalcin, their running performance matched that of the healthy 3-month-old mice, researchers said.
 
The older mice were able to run about 1,200 metres before becoming exhausted. "It was extremely surprising that a single injection of osteocalcin in a 12-month-old mouse could completely restore its muscle function to that of a 3-month-old mouse," said Karsenty.
 
To determine the cellular mechanisms behind osteocalcin's effects, the team measured levels of glycogen, glucose, and acylcarnitines (an indicator of fatty-acid use) in mice with and without osteocalcin.
 
The researchers determined that the hormone helps muscle fibres uptake and catabolise glucose and fatty acids as nutrients during exercise.
 
"Osteocalcin is not the only hormone responsible for adaptation to exercise in mice and humans, but it is the only known bone-derived hormone that increases exercise capacity. This may be one way to treat age-related decline in muscle function in humans," said Karsenty.
 
The study was published in the journal Cell Metabolism.

 
 
 
 
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