A promising health news item from mid-August was a release from NewScientist.com labeled “ “Three years more life for 15 minutes of exercise a day“.
The basic story is that people who move, even if for only 15 minutes each day, outlive people who do not.
The study was based on information from more than 400,000 people in Taiwan over an eight-year period. Chi-Pang Wen from the National Health Institutes in Taipei, Taiwan led the study. Participants were grouped by the amount and vigorousness of their chosen exercise.
The data showed that 15 minutes of daily moderate exercise (or a weekly total of 90 minutes moderate exercise) like walking briskly, could add three years to the exercisers’ life expectancy. Wen and colleagues found that the health benefits extended to all exercisers no matter the activity, although the benefits increased proportionally to the intensity of the activity.
Even smokers and participants with underlying disease such as diabetes saw a benefit.
These encouraging results, reported in The Lancet, will ideally be tested in other parts of the world to prove that the health benefits translate to other climates and types of people.
Fifteen minutes a day to add three years. Take someone along, and your kids (or the dog) could benefit at the same time.
If three additional years doesn’t excite you, the study also found a 10% decrease in the risk of cancer, and a 20% decrease in the risk of heart disease with this minimal amount of exercise.
Next some interesting news about evolution in plants. I must admit that never during my education in biology (nor during hours in the garden) have I thought about plant evolution, so this piece definitely got the neurons firing.
Published in the journal Science, the study’s authors note that the “advent of wood (secondary xylem) occurred during the Paleozoic era”. This system of xylem is what allowed the flow of nutrients and water up into and thus the development of larger woody plants.
The researchers found plant fossils from the early Devonian period (approximately 407 million years ago) with secondary xylem including simple rays, representing the earliest evidence to date of secondary woody material in early plants. As explained by Phillipe Gerrienne et al., “The small size of the plants and the presence of thick-walled cortical cells confirm that wood early evolution was driven by hydraulic constraints and not by the need for support.”
Finally and most recently, a late August report from Nature magazine (S. A. Villeda et al.) “The ageing systemic milieu negatively regulates neurogenesis and cognitive function,” heralds a new job for the blood component eotaxin. This molecule, formerly known as a chemoattractant for eosinophils, was found to affect neurogenesis when given to mice.
Neuron growth was examined in young and old mice, and those treated with the plasma from old mouse blood showed below average neuron formation, while older mice exposed to plasma from young mice showed above normal neuron formation.
This lead investigators to examine young mice for a blood component that blocks the usual decrease in neural development in older mice.
It appears that eotaxin or CCL1 is the blood factor blocking neurogenesis, possibly at the level of immune cells such as microglia. When young mice were treated with CCL1 plus an antibody to block CCL1, the anti-neurogenesis effect was blocked.
The researchers also measured blood levels of CCL1 and found these levels to be higher in older mice and older humans.
An article in The Scientist August 31, contained this quote from a surprised Dr. Richard Ransohoff of the Cleveland Clinic Lerner College of Medicine, about CCL1:
It’s a chemokine that has zero prior neurobiology.
Ransohoff notes the need to next find out whether the CCL1 effect carries over to other mouse varieties.
This is very exciting news, that eotaxin might “affect the decline in neurogenesis”, as Fred Gage from the Salk Institute says, but the mechanism of action is not yet known. Gage feels the effect is possibly not caused directly by CCL1, rather by some other cells that the chemokine acts on.
Challenged by a corn maze this fall? Could your eotaxin level be to blame?