RESUMO
α-ketoglutarate (KG), also referred to as 2-oxoglutarate, is a key intermediate of cellular metabolism with pleiotropic functions. Cell-permeable esterified analogs are widely used to study how KG fuels bioenergetic and amino acid metabolism and DNA, RNA, and protein hydroxylation reactions, as cellular membranes are thought to be impermeable to KG. Here we show that esterified KG analogs rapidly hydrolyze in aqueous media, yielding KG that, in contrast to prevailing assumptions, imports into many cell lines. Esterified KG analogs exhibit spurious KG-independent effects on cellular metabolism, including extracellular acidification, arising from rapid hydrolysis and de-protonation of α-ketoesters, and significant analog-specific inhibitory effects on glycolysis or mitochondrial respiration. We observe that imported KG decarboxylates to succinate in the cytosol and contributes minimally to mitochondrial metabolism in many cell lines cultured in normal conditions. These findings demonstrate that nuclear and cytosolic KG-dependent reactions may derive KG from functionally distinct subcellular pools and sources.
Assuntos
Aminoácidos/metabolismo , Metabolismo Energético , Ésteres/metabolismo , Ácidos Cetoglutáricos/metabolismo , Mitocôndrias/metabolismo , Ácido Succínico/metabolismo , Animais , Linhagem Celular Tumoral , Citosol/metabolismo , Ésteres/química , Glicólise , Células HEK293 , Humanos , Hidrólise , Interações Hidrofóbicas e Hidrofílicas , Ácidos Cetoglutáricos/química , Camundongos , Consumo de Oxigênio , Células RAW 264.7RESUMO
In 2012, AstraZeneca entered into a strategic relationship with Charles River Laboratories whereby preclinical safety packages comprising safety pharmacology, toxicology, formulation analysis, in vivo ADME, bioanalysis and pharmacokinetics studies are outsourced. New processes were put in place to ensure seamless workflows with the aim of accelerating the delivery of new medicines to patients. Here, we describe in more detail the AstraZeneca preclinical safety outsourcing model and the way in which a collaborative tool has helped to translate the processes in AstraZeneca and Charles River Laboratories into simpler integrated workflows that are efficient and visible across the two companies.