SummaryLow-dose exposures to common environmental chemicals that are deemed safe individually may be combining to instigate carcinogenesis, thereby contributing to the incidence of cancer. This risk may be overlooked by current regulatory practices and needs to be vigorously investigated.
Cancer chemoprevention is a strategy taken to retard, regress, or resist the multistep process of carcinogenesis, including the blockage of its vital morphogenetic milestones viz. normal-preneoplasia-neoplasia-metastasis. For several reasons, including safety, minimal (or no) toxicity and side-effects, and better availability, alternatives such as naturally occurring phytochemicals that are found in foods are becoming increasingly popular over synthetic drugs. Food saponins have been used in complimentary and traditional medicine against a variety of diseases including several cancers. Diosgenin, a naturally occurring steroid saponin found abundantly in legumes and yams, is a well-known precursor of various synthetic steroidal drugs that are extensively used in the pharmaceutical industry. Over the past decade, a series of preclinical and mechanistic studies have been conducted to understand the role of diosgenin as a chemopreventive/therapeutic agent against several cancers. This review highlights the biological activity of diosgenin that contributes to cancer chemoprevention and control. The anticancer mode of action of diosgenin has been demonstrated via modulation of multiple cell signaling events involving critical molecular candidates associated with growth, differentiation, apoptosis, and oncogenesis. Altogether, these preclinical and mechanistic findings strongly implicate the use of diosgenin as a novel, multitarget-based chemopreventive or therapeutic agent against several cancer types. Future research in this field will help to establish not only whether diosgenin is safe and efficacious as a chemopreventive agent against several human cancers, but also to develop and evaluate standards of evidence for health claims for diosgenin-containing foods as they become increasingly popular and enter the marketplace labeled as functional foods and nutraceuticals.
Engineered metal/mineral, lipid and biochemical macromolecule nanomaterials (NMs) have potential applications in food. Methodologies for the assessment of NM digestion and bioavailability in the gastrointestinal tract are nascent and require refinement. A working group was tasked by the International Life Sciences Institute NanoRelease Food Additive project to review existing models of the gastrointestinal tract in health and disease, and the utility of these models for the assessment of the uptake of NMs intended for food. Gastrointestinal digestion and absorption could be addressed in a tiered approach using in silico computational models, in vitro non-cellular fluid systems and in vitro cell culture models, after which the necessity of ex vivo organ culture and in vivo animal studies can be considered. Examples of NM quantification in gastrointestinal tract fluids and tissues are emerging; however, few standardized analytical techniques are available. Coupling of these techniques to gastrointestinal models, along with further standardization, will further strengthen methodologies for risk assessment.
Nutritional support in patients with advanced cirrhosis is difficult due to protein, fluid and salt restrictions. Successful liver transplantation should improve nutrient tolerance. We randomly assigned 28 hypoalbuminemic cirrhotic patients to receive, immediately after liver transplantation, one of three regimens: group 1, no nutritional support (n = 10); group 2, total parenteral nutrition (TPN) (35 kcal/kg/day) with standard amino acids (1.5 g/kg/day) (n = 8); or group 3, isocaloric isonitrogenous TPN with added branched-chain amino acids (n = 10). Therapy was continued for 7 days posttransplant. Jaundice resolution was unaffected by nutritional support. Nitrogen balance favored both TPN groups. Branched-chain amino acid (BCAA) aromatic amino acid ratios were highest in group 3. Coma scores and serum ammonia levels were similar in all groups. Both TPN groups achieved respirator independence earlier; this difference was not statistically significant. Group 1 patients stayed longest in ICU; the difference was statistically significant. TPN with either standard or BCAA- enriched amino acids is tolerated well immediately after successful liver transplant. Positive nitrogen balance is achieved; large protein loads do not worsen encephalopathy. Nutritional support may improve respiratory muscle function, allowing earlier weaning from ventilatory support. A shortened length of ICU stay justifies the expense of TPN.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.