Diosgenin, a Steroid Saponin Constituent of Yams and Fenugreek: Emerging Evidence for Applications in Medicine

Phytochemicals found in foods and spices are progressively gaining popularity over conventional synthetic drugs mainly because they act via multiple molecular targets that synergize to efficiently prevent or treat chronic illnesses. Phytochemicals are also safe (with minimal or no toxic or side effects) with better bioavailability. Food saponins have been used in complimentary and traditional medicine against a variety of diseases including several cancers. Diosgenin, a naturally-occurring steroid saponin is found abundantly in legumes (Trigonella sp.) and yams (Dioscorea sp.). Diosgenin is a precursor of various synthetic steroidal drugs that are extensively used in the pharmaceutical industry. Over the past two decades, a series of pre-clinical and mechanistic studies have been independently conducted to understand the beneficial role of diosgenin against metabolic diseases (hypercholesterolemia, dyslipidemia, diabetes and obesity), inflammation and cancer. In experimental models of obesity, diosgenin decreases plasma and hepatic triglycerides and improves glucose homeostasis plausibly by promoting adipocyte differentiation and inhibiting inflammation in adipose tissues. A limited number of experiments have been conducted to understand the preclinical efficacy of diosgenin as a chemopreventive/therapeutic agent against cancers of several organ sites. Mechanistic studies using in vitro models suggest that diosgenin suppresses cancer cell growth through multiple cell signaling events associated with proliferation, differentiation, apoptosis, inflammation and oncogenesis. This chapter provides a comprehensive review of the biological activity of diosgenin that contributes to several diseases in its role as a health beneficial phytochemical by citing new studies. In addition, diosgenin’s safety with regards to its potential toxicity is also critically discussed. Altogether, the findings from pre-clinical and mechanistic studies strongly implicate the use of diosgenin as a novel multi-target based chemopreventive or therapeutic agent against several chronic diseases.