Horny Goat Weed ~ Of all the supplements available on the market, Horny Goat Weed – Latin name Herba epimedii – has the raunchiest image. Flavonoid extracts of this plant are found in lots of sex supplements that promise users more lust and more and harder erections. Researchers at Fudan University in Shanghai have been studying another property of Horny Goat Weed and think that flavonoids in the sex-enhancing herb extend life expectancy.
Laboratories are on to a whole range of substances that extend the life expectancy of Caenorhabditis elegans at least, a measly little worm consisting of fewer than 300 cells. Some substances activate AMPK, others neutralise free radicals, some do something to neurotransmitters, and yet others – which are less interesting for humans – extend life expectancy by blocking the key anabolic molecule mTOR.
Many natural substances, found in berries, green tea and turmeric extend life expectancy and inhibit aging diseases. So, the Chinese reasoned, why wouldn’t icariin, a flavonoid and active ingredient in Horny Goat Weed, do the same?
The structural formula of icariin is shown below on the left. In the body, one of icariin’s two sugar groups disappears, and the compound icaride II is formed as a result, shown on the right below.
The researchers added icariin and icariside II in different concentrations to the medium that their lab worms were feeding on, and discovered that a lower concentration of icariside II than icariin had an optimal effect on life expectancy.
Icariin and icariside II also extended life expectancy when exposed to 35 degrees Celsius and when hydrogen peroxide was added to the medium on which the worms were feeding. The compounds seem to protect against heat stress and free radicals.
Icariin and icariside II extended the life expectancy of the worms by over twenty percent. The researchers repeated their experiment with icariside I (the analogue of icariin in which the lowest sugar group is missing instead of the left hand sugar group) and icaritin (the completely ‘stripped’ analogue of icariin, which has no sugar group at all). Icariside I and icaritin did not extend life expectancy.
As the worms aged the number of aberrant protein complexes [aggregates] in their body increased. Similar processes occur at an accelerated rate in the brains of people with Parkinson’s or Alzheimer’s. Icariside II inhibited this process, as the figures below show.
The researchers discovered that the Horny Goat Weed compounds work through signal molecules in the cell which are activated by insulin and IGF-1.
“Given the extensive protective effects and safe long term use of icariin and icariside II in humans, they may serve as promising anti-aging candidates in the future”, the researchers conclude.
