Celebrating 120 Years of Butantan Institute Contributions for Toxinology

This is collection of original and review articles selected in recognition of the contribution of Instituto Butantan to the field of toxinology and its continued and relevant role in this field in the 120 years since its foundation. Congratulations to the Butantan Institute, its house scientists, and collaborators on its 120th anniversary

Thai traditional medicine as a source for cancer prevention: from local concepts to the discovery of potential chemopreventive extracts

Cancer chemoprevention aims to prevent, delay, or reverse carcinogenesis. Thai Traditional Medicine (TTM) could be a source for cancer chemopreventive agents and – more broadly –could play a role in cancer prevention. Using an ethnopharmacology approach this thesis aims to understand the pharmacological basis of some of these botanical drugs and to discover new extracts which could be useful in cancer prevention. Interviews with 33 TTM practitioners revealed the five characteristics of cancer in TTM (mareng), which is described as an accumulation of waste, chronic inflammation, chronic illnesses (krasai), bad condition of body fluids (‘luead’ and ‘namlueang’), and imbalance of dhātu si. Further analysis of preventive methods led to the five strategies for preventing mareng. To link TTM actions to pharmacology, we proposed that three strategies, removal of waste, liver protection, and prevention from krasai, can be linked to the antioxidant system. After screening of fifty-two extracts, fifteen exhibited protective effect in a liver cancer cell line. Among them, ethanol extracts of Thunbergia laurifolia leaves (TLe) and Senegalia rugata leaves (SR1e) exhibited the most potent activities in the induction of NQO1 enzyme and glutathione. Upregulation of antioxidant genes and radical scavenging were among their protective mechanisms. While TLe induced NQO1 expression, SR1e upregulated the expression of Nrf2. Both extracts did not induce CYP1A1 expression nor reduce cell viability of primary rat hepatocytes which provided preliminary safety profile. Using HPLC-HRMS-SPE-ttNMR, we could identify some active constituents in the extracts. This is the first report analysing how cancer is perceived in TTM, what prevention strategies are used, linking this to pharmacological models, and on chemopreventive properties of TLe and SR1e and some of their constituents. The evidence supports the potential use of these medicinal plants in cancer prevention. Future work should be performed with more TTM practitioners and use in vivo models