Ashwagandha:and its use with chemotherapy and radiation treatment
The plant Ashwagandha ( Withania somnifera ) is widely used in Ayurvedic medicine, the traditional medical system of India . It is an ingredient in many formulations prescribed for a variety of musculoskeletal conditions (arthritis, rheumatism etc.) and as a general tonic to increase energy, improve overall health and longevity, and prevent disease in athletes, the elderly and during pregnancy. Pharmacological studies have validated its use in inflammatory arthritis    and animal studies have shown it useful as an anti stress agent   .
In the past we have occasionally used this herb for its anti stress effects to help relieve the deep fatigue that often results from contemporary cancer treatments. Several studies have examined the antitumor and radiosensitizing effect of Ashwagandha. There are more reasons to use Ashwagandha than we previously suspected.
One study looked at the effect of giving Ashwagandha to test mice that were fed a chemical (urethane) that causes lung cancer. Of the mice fed only the carcinogen, 100% developed cancer. Of those fed Ashwagandha along with the carcinogen only 25% developed cancer. Those mice who were fed Ashwagandha and who didn't develop cancer had normal healthy looking lungs. 
In another experiment tumor cells (Sarcoma 180) were transplanted into mice. Administration of Ashwagandha to these mice at 400 mg/Kg produced complete regression of the tumor growth. 
I find it interesting that many of the effects of Ashwagandha parallel those of Quercetin and Curcumin. Therapeutically all three have a history of similar uses: as an anti inflammatory in rheumatic diseases, all three have profound anti oxidant effects and all three have the same action of apparently making cancer cells more sensitive to radiation and chemotherapy. Ashwagandha appears to have several other effects desirable during cancer treatment which I don't associate with these other herbs.
Ashwagandha extracts have immunomodulating effects. They mobilize the white blood cells making them more capable of protecting the body.  Perhaps more importantly these extracts protect the immune system from suppression by chemotherapy and steroids  . Other studies suggest that Ashwagandha can protect the bone marrow from injury from chemotherapy preventing the severe decrease in white blood cells that leaves may cancer patients prone to infection or unable to continue treatment. 
Much of the research I'm quoting is preliminary, using animal models and lacking the human clinical trials we prefer. Nonetheless the results are tantalizing.
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