Dioscorea villosa

Dioscorea villosa is a deciduous herbaceous perennial plant that grows counterclockwise on small to medium-sized shrubs. The upper leaves are alternate, heart-shaped and shiny with long petioles. The lower leaves are usually spirally arranged. The plants are dioecious. The small (male) staminate flowers are white and fragrant, arranged in panicles, while the carpal(female) plants produce small solitary flowers at leaf nodes. The fruit is a membranous 3-valved capsule with one or two chocolate-colored winged seeds. The long, cylindrical, rarely branched rhizomes reach 5-10 mm in diameter, with numerous tenacious, thin roots attached below. The part used medicinally is the rhizome the tuber and the dried roots.

Various effects of diosgenin, including anti-cancer, on cardiovascular problems, anti-hyperlipidemia, type 2 diabetes, and neuro-protective effects have been studied in animal and in vitro work. In particular, a crossover, randomized, double-blind, placebo-controlled study revealed that treatment with a yam extract enriched in diosgenin improved cognitive function in healthy human adults without additional adverse effects. Modern therapeutic use of Dioscorea villosa reflects pharmacological research and traditional indications. Naturopathic uses include spasmodic conditions of the gastrointestinal tract and spasmodic pain of dysmenorrhea. The second volume of the British Herbal Compendium (2006) lists similar indications, but also emphasizes beneficial anti-inflammatory action in the acute stages of rheumatoid arthritis and in musculoskeletal disorders in general.

This bioactive phytochemical has shown high potential and interest in the treatment of various disorders such as cancer, diabetes, arthritis, asthma, and cardiovascular disease, as well as being an important starting material for the preparation of numerous steroidal drugs in the pharmaceutical industry. Preclinical studies have shown promising effects on cancer, neuroprotection, atherosclerosis, asthma, bone health, and other diseases. Clinical investigations have demonstrated the nontoxic nature of diosgenin and promising benefits on cognitive function and menopause. However, further well-designed clinical studies are needed to address the other effects observed in preclinical studies, as well as a better understanding of the safety profile of diosgenin.

Research on the medicinal value of wild yam root extract (WYE) has shown evidence suggesting antitumor properties particularly for breast cancer and in both hormone receptor-positive and triple-negative breast cancers (TNBCs), where it alters the DNA epigenetic patterns of 5-hydroxymethylcytosine , induces toxicity, arrests the cell cycle, inhibits fatty acid synthase, and modifies the activity of estrogen and progesterone hormone receptors.

According to Traditional Chinese Medicine it is a plant with a neutral nature, sweet taste, the meridians involved are Spleen, Lung, Kidney, tonifying Qi of Spleen and Stomach and nourishing the Yin of Stomach. It strengthens and supports lung and kidney, tonifying the Here and Yin of lung and nourishing the Yin of lung. Nourishes the 5 organs.

BIBLIOGRAPHY

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