Resveratrol In Red Wine Might Prevent Weakening of Astronauts’ Muscles

Atrophied muscles are no good to anyone, most of all to astronauts spending as long as nine months cooped-up inside a spaceship bound for Mars.

Out in space and without gravity, muscles and bones weaken. Weight-bearing muscles suffer first and worst, like the soleus muscle in our calves.

Human muscles will waste away in the absence of gravity due to lack of physical activity. Mitigating this enormous challenge remains one of the toughest problems vexing NASA to this day.

NASA said its studies have shown that astronauts experience up to a 20 percent loss of muscle mass on spaceflights lasting five to 11 days. Imagine what this loss of muscle mass will be on a 270 day-long voyage to Mars.

Consequently, the loss of muscle mass means a loss of strength that can be potentially dangerous if an astronaut must perform a strenuous emergency procedure upon re-entry into the Earth's gravitational field.

NASA says maintaining muscle in space is a concern, especially for long-duration space missions such as those to Mars. Right now, the only way to minimize muscle atrophy in space is through intensive exercise (up to 2 1/2 hours per day), particularly strength training exercises combined with an adequate diet.

However, researchers at Harvard might have discovered a way to help maintain muscle mass and avoiding atrophy apart from exercise.

A study by these researchers published in Frontiers in Physiology, shows that resveratrol substantially preserves muscle mass and strength in rats exposed to the wasting effects of simulated Mars gravity.

Resveratrol that is present in red wine is a natural phenol found in the skin of grapes, blueberries, raspberries, mulberries, and peanuts. It's widely used as a dietary supplement and has as been widely investigated for its anti-inflammatory, anti-oxidative, and anti-diabetic effects.

“Dietary strategies could be key, especially since astronauts travelling to Mars won't have access to the type of exercise machines deployed on the ISS,” said Dr. Marie Mortreux, lead author of the NASA-funded study at the laboratory of Dr. Seward Rutkove, Beth Israel Deaconess Medical Center, Harvard Medical School.

Dr. Mortreux said resveratrol has been shown to preserve bone and muscle mass in rats during complete unloading, analogous to microgravity during spaceflight.

“So, we hypothesized that a moderate daily dose would help mitigate muscle deconditioning in a Mars gravity analogue, too."

During the experiment, 24 male rats were exposed to normal loading (Earth) or 40 percent loading (Mars) for 14 days. In each group, half received resveratrol (150 mg/kg/day) in water. The others got just water. Otherwise, they fed freely from the same chow.

As expected, the 'Mars' condition weakened the rats' grip and shrank their calf circumference, muscle weight and slow-twitch fiber content.

Incredibly, however, resveratrol supplementation almost entirely rescued front and rear paw grip in the Mars rats to the level of the non-supplemented Earth rats.

What's more, resveratrol completely protected muscle mass (soleus and gastrocnemius) in the Mars rats. More impressive, it slowed the loss of slow-twitch muscle fibers.

"Resveratrol treatment promotes muscle growth in diabetic or unloaded animals, by increasing insulin sensitivity and glucose uptake in the muscle fibers,” said Dr. Mortreux.

“This is relevant for astronauts, who are known to develop reduced insulin sensitivity during spaceflight."

The anti-inflammatory effects of resveratrol might also help conserve muscle and bone, and other anti-oxidant sources such as dried plums are being used to test this.