Global losses of foodstuffs due to mycotoxins run into millions of tons annually. In North America, an estimated $5 billion is lost annually as a result of mycotoxins contamination, and the worst culprits are aflatoxins, produced by Aspergillus flavus and Aspergillus parasiticus. Little wonder then that Dr. Jia-Sheng Wang, University of Georgia, took center stage for the Translational Impact Award Lecture during the 2018 SOT Annual Meeting and ToxExpo to deliver a talk aptly titled "Modulation of Toxic Effects and Human Disease Risks: From Synthetic Drugs to Natural Products.”
Dr. Wang’s lecture was as lively as it was informative, and it shed further light on the pains and gains of clinical research. By way of introduction, Dr. Wang highlighted the health problems associated with aflatoxins, and these included immunosuppression, carcinogenesis, and growth retardation in children.
In collaboration with an analytical chemist, Dr. Wang explored the mitigation of aflatoxin M1 using a synthetic dithiolethione compound, oltipraz. A series of experiments revealed that oltipraz possessed potent anti-angiogenic properties and the ability to induce phase II detoxification enzymes such as NAD(P)H:quinone oxidoreductase 1 (NQO1) and glutathione S-transferase (GST). Unfortunately, this endeavor hit a brick wall as the clinical trials failed.
Undaunted, Dr. Wang turned his attention to green tea polyphenols (GTP). He leveraged on the impressive resumé of GTP garnered across several studies. Most importantly, GTP was found to suppress aflatoxin B1-induced chromosomal aberrations in vivo. Tenaciously, Dr. Wang and his co-workers sought to address the gap arising from inconsistent epidemiological studies, which were due to the absence of biomarkers for green tea consumption. The design of their intervention clinical trial of GTP in humans was aimed at validating biomarkers such as epicatechin (EC), epicatechin-3-gallate (ECG), epigallocatechin (EGC), epigallocatechin-3-gallate (EGCG), and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in urinary and plasma samples. Over 11,000 cohorts were used in the course of two short-term (three months) and long-term (three years) studies.
In a bid to sound the final death knell on the menace of aflatoxins, Dr. Wang went back, cap in hand, to Mother Nature. This time around, he used natural clay, branded NovaSil clay, to ameliorate the effects of aflatoxins. To this end, a short-term randomized and double-blinded clinical trial of NovaSil clay was evaluated in Texas. Other clinical intervention studies conducted in the African countries of Ghana and Kenya further confirmed the safety and potential of NovaSil clay to reduce the biomarkers of aflatoxin exposure.
This systematic search for effective agents against aflatoxins is not just a public health effort, but is more like a scientific agenda against economic and health drain!
This blog was prepared by an SOT Reporter. SOT Reporters are SOT members who volunteer to write about sessions and events they attend during the SOT Annual Meeting and ToxExpo. If you are interested in participating in the SOT Reporter program in the future, please email SOT Communications Director Michelle Werts.