From Ergo Log
Athletes who are no longer in the prime of their youth can do themselves a favour by taking extracts of the leaves of an ancient tree, Ginkgo biloba. At least, if you extend the results of an animal study published in PLoS One to include humans. The extracts have an anabolic effect in older rats: they reverse catabolic ageing processes in muscle tissue.
Ginkgo biloba is an interesting longevity supplement. In animal and epidemiological studies, ginkgo extracts extend lifespan. Studies on worms have shown that ginkgo extracts protect muscle tissue from the degeneration that happens with ageing. The researchers, who work at research institutes in France such as Inserm and CNRS, were particularly interested in the latter aspect. They wondered whether Ginkgo biloba works against sarcopenia.
Sarcopenia is the scientific term for the weakening that occurs as a result of ageing. Muscles lose their strength and ability to function as people age. But we don’t know exactly how this happens. Ageing probably something like a cascade of catabolic processes.
The researchers did a study using old rats, aged 22 months. They were given 75 mg per kg bodyweight of ginkgo extract in their drinking water each day for 2 months. The extract used was Egb 761, from the French supplier Ipsen. A control group of elderly rats got no ginkgo. A second control group was made up of young 4-month-old rats. They got no ginkgo either.
After 60 days the researchers measured the effect that the ginkgo extract had had in the soleus calf muscle. Of course we are just dumb journalists with no real understanding of these matters, but we think this was a strange choice of muscle. The soleus is not that sensitive to ageing processes. A different calf muscle, the gastrocnemius reacts more to ageing. It’s just possible that this study underestimates the anabolic effect of ginkgo.
At the end of the course of ginkgo, when the researchers examined the old rats, they saw that the extracts protected the rats against weight gain in old age. Elderly lab rats grow fat. What’s more, the rats that had been given ginkgo had more muscle tissue.
The effect of the ginkgo was not so great that the old rats’ muscle tissue ended up like that of young animals.
The rats who’d been given ginkgo supplements also developed more muscle strength. The researchers discovered this when they made muscle fibres from the rats’ soleus contract, and measured how much strength the fibres could generate.
The ginkgo supplementation had an effect on the concentration of the enzyme creatine kinase in the rats’ blood. This is a marker for muscle damage. The more creatine kinase in the blood, the worse off the muscles are. The young animals had 370 U/L in their blood. In the elderly rats that got nothing, the figure was 737 U/L. In the elderly rats that were given ginkgo, the creatine kinase level dropped to 371 U/L.
The reason that the French research was published in such a prestigious scientific journal as PLoS One is that the researchers used genomics technology to measure the activity of tens of thousands of genes in the DNA of the muscle cells. That’s how they discovered that the ginkgo supplement had an effect on 1015 of those genes.
The most important of those genes were connected to the production of muscle tissue, such as the genes for follistatin, follistatin related protein, activin receptor type I, embryonic myosin heavy chain and ryanodine receptor 3, and they all became more active. Other genes also reacted to the ginkgo: some got the muscle cells to burn more fatty acids, others reduced the amount of free radicals that the mitochondria in the muscle cells produced, and yet others made the muscle cells use less glucose as a source of energy.
The ginkgo also made the gene for tenascin C work twice as hard as normal. Tenascin C is a molecule found in muscle attachments. It’s a component of collagen I and II. So gingko not only increases muscle mass and strength, but also strengthens the muscle attachments.
The researchers think that Ginkgo biloba may protect the elderly against sarcopenia. If they are right, it will give life extensionists a new way to maintain muscle condition. So far longevity seekers have had to rely on caloric restriction and strength training.
PLoS One. 2009 Nov 24;4(11):e7998.