The Anticancer Action of Yizhihao, a Folk Herb of Xinjiang
The Qing-dynasty physician Zhao Xuemin wrote in Bencao Gangmu Shiyi (Supplement to the Compendium of Materia Medica): "Li Bingwen, an assistant prefect in Shaoxing, long stationed on the frontier, said that in Barkol there grows a medicinal herb called Yizhihao. It grows in deep mountains, with no branches or leaves; a single shoot springs from the earth, its smell like that of mugwort. In the fourth lunar month, grooms drive horses into the mountains, gather the herb, bring it home, and decoct it into a paste to sell to traveling merchants; some peddle it as far as Lanzhou for sale. It activates blood and resolves toxin, removes all kinds of accumulation and stagnation, deep-rooted chronic cold disorders, and dispels wind and regulates deficiency." This passage shows that long ago, people in Xinjiang used Yizhihao to treat various diseases, and they even sold paste made from it as far away as Lanzhou.
The Barkol Zhao Xuemin mentioned is today's Barkol Kazakh Autonomous County in Hami, Xinjiang Uyghur Autonomous Region. The Yizhihao he described is the whole herb of Aihao (Artisia rupestris), a member of the daisy family. Aihao grows on dry slopes, desert grasslands, meadows, alluvial plains, and dry river valleys at altitudes of 1,100–2,900 m, mainly distributed in Xinjiang. It is a perennial herb reaching 20–50 cm in height, with a distinctive fragrance throughout.
Yizhihao is a commonly used herb in Xinjiang, where people mainly use it for overeating, indigestion, stomachache, and abdominal fullness. Traditional TCM considers it wind-dispersing and exterior-releasing, stomach-strengthening and accumulation-resolving, blood-activating and toxin-resolving. Besides indigestion, Yizhihao also treats wind-cold common cold, bruises with stasis and swelling, venomous snakebite, and urticaria. According to Zhongguo Minzu Yao Zhi (Records of Chinese Ethnic Medicines), using 15–24 g of Yizhihao decocted in water as a tea, while simultaneously washing the affected area with a decoction, treats venomous snakebite and urticaria. A paste made by simmering Yizhihao and applied to the affected area treats neurodermatitis.
Yizhihao also has anticancer action. Modern pharmacological studies have confirmed that total flavonoids from Yizhihao can induce tumor cell differentiation and markedly inhibit tumor cell proliferation and DNA synthesis; their induction of apoptosis begins at the G0/G1 phase of the cell cycle. When liver cancer cells are treated with total flavonoids of Yizhihao, there is substantial expression of wild-type P53 gene (the famous tumor suppressor gene), which may be one of the molecular mechanisms by which Yizhihao clears malignant cells from the body and enhances immune function. From this standpoint, taking Yizhihao extract internally is consistent in principle with modern immunotherapy.
Yizhihao extract also has hepatoprotective, free-radical-scavenging, and anti-allergic effects. A large dose of Yizhihao extract significantly lowers serum alanine aminotransferase in mice with immune hepatitis. Yizhihao also inhibits smooth muscle contraction.
There is another Chinese medicinal called Xueshang Yizhihao (Aconiti brachypodi Radix); it is a completely different plant from Xinjiang Yizhihao. Xueshang Yizhihao is Aconitum racemulosum of the buttercup family, mainly produced in Yunnan and elsewhere. It is highly toxic and is a controlled medicine. Xinjiang Yizhihao, by contrast, has very low toxicity: the intraperitoneal LD50 of an alcohol-precipitated water decoction in mice is 23.91 g/kg, while the adult daily dose of Yizhihao is only 10–30 g, so conventional doses are very safe.
From Zhao Xuemin's record we can see that people in Xinjiang in the past took Yizhihao as a decocted paste, which is easy to take and carry. Today's cancer patients taking Xinjiang Yizhihao for anticancer and immune-boosting purposes may still follow this ancient practice: simmer Xinjiang Yizhihao alone or together with other anticancer herbs into an electuary paste and take it daily.
Some pharmaceutical companies have also made a Chinese patent medicine called Fufang Yizhihao Keli (Compound Yizhihao Granules), but this granule is mainly used for sore throat from the common cold; its ingredients also include Daqingye (Isatidis Folium) and Banlangen (Isatidis Radix). Leukemia patients of the heat-toxin excess type could take it, but cancer patients of the spleen-stomach deficiency-cold type would not be suited to such a patent medicine.