RESUMEN
Liver cancer is one of the most common cancer worldwide with a high mortality. Methionine is an essential amino acid required for normal development and cell growth, is mainly metabolized in the liver, and its role as an anti-cancer supplement is still controversial. Here, we evaluate the effects of methionine supplementation in liver cancer cells. An integrative proteomic and metabolomic analysis indicates a rewiring of the central carbon metabolism, with an upregulation of the tricarboxylic acid (TCA) cycle and mitochondrial adenosine triphosphate (ATP) production in the presence of high methionine and AMP-activated protein kinase (AMPK) inhibition. Methionine supplementation also reduces growth rate in liver cancer cells and induces the activation of both the AMPK and mTOR pathways. Interestingly, in high methionine concentration, inhibition of AMPK strongly impairs cell growth, cell migration, and colony formation, indicating the main role of AMPK in the control of liver cancer phenotypes. Therefore, regulation of methionine in the diet combined with AMPK inhibition could reduce liver cancer progression.
Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Metionina/farmacología , Adenosina Trifosfato/metabolismo , Proliferación Celular/efectos de los fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Metionina/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
By combining NMR spectroscopy, transmission electron microscopy, and circular dichroism we have identified the structural determinants involved in the interaction of green tea catechins with Aß1-42, PrP106-126, and ataxin-3 oligomers. The data allow the elucidation of their mechanism of action, showing that the flavan-3-ol unit of catechins is essential for interaction. At the same time, the gallate moiety, when present, seems to increase the affinity for the target proteins. These results provide important information for the rational design of new compounds with anti-amyloidogenic activity and/or molecular tools for the specific targeting of amyloid aggregates in vivo.