Untargeted Metabolomic Analysis Combined With Multivariate Statistics Reveal Distinct Metabolic Changes in GPR40 Agonist-Treated Animals Related to Bile Acid Metabolism

Abstract

Metabolomics has been increasingly applied to biomarker discovery, as untargeted metabolic profiling represents a powerful exploratory tool for identifying causal links between biomarkers and disease phenotypes. In the present work, we used untargeted metabolomics to investigate plasma specimens of rats, dogs, and mice treated with small-molecule drugs designed for improved glycemic control of type 2 diabetes mellitus patients via activation of GPR40. The in vivo pharmacology of GPR40 is not yet fully understood. Compounds targeting this receptor have been found to induce drug-induced liver injury (DILI). Metabolomic analysis facilitating an integrated UPLC-TWIMS-HRMS platform was used to detect metabolic differences between treated and non-treated animals within two 4-week toxicity studies in rat and dog, and one 2-week toxicity study in mouse. Multivariate statistics of untargeted metabolomics data subsequently revealed the presence of several significantly upregulated endogenous compounds in the treated animals whose plasma level is known to be affected during DILI. A specific bile acid metabolite useful as endogenous probe for drug–drug interaction studies was identified (chenodeoxycholic acid-24 glucuronide), as well as a metabolic precursor indicative of acidic bile acid biosynthesis (7α-hydroxy-3-oxo-4-cholestenoic acid). These results correlate with typical liver toxicity parameters on the individual level.

Learn from failures and stay hopeful to GPR40, a GPCR target with robust efficacy, for therapy of metabolic disorders

“…Multiple mechanisms had been linked to the liver toxicity caused by GPR40 partial and AgoPAM agonists, including acyl glucuronidation ( Otieno et al, 2018 ; Qiang and Zhang, 2019 ; Shang et al, 2020 ; Zhu et al, 2022 ), inhibition of mitochondrial respiration ( Otieno et al, 2018 ), inhibition of bile acid transporters ( Li et al, 2015 ; Bazydlo-Guzenda et al, 2021a ), generation of reactive oxygen species ( Kim et al, 2018 ), and increase in bile acid biosynthesis ( Doerfler et al, 2020 ) ( Figure 2 ). As medium- and long-chain fatty acids are endogenous ligands of GPR40, carboxylic acid headgroup is a key feature of most GPR40 agonists ( Table 1 ), which has been known in many compounds to cause idiosyncratic drug toxicities by forming reactive acyl glucuronide metabolites ( Lassila et al, 2015 ).…”

“…Mosedale et al used mouse genetics to study the mechanism of TAK-875-induced liver toxicity and found that TAK-875 treatment caused changes of genes in immune responses and bile acid homeostasis, as well as oxidative stress and mitochondrial dysfunction ( Mosedale et al, 2021 ). Doerfler et al reported that chronic treatment of GPR40 partial agonist, BI-2081, for 4 weeks induced bile acid synthesis in rats and dogs, specifically 7a-Hydroxy-3-oxo-4-cholestenoic acid, which was correlated with increase in blood levels of liver enzymes including AST, ALT, and alkaline phosphatase (ALP) ( Doerfler et al, 2020 ). SCO-267 was also reported to be converted to acyl glucuronide metabolites in a metabolite profiling study by using human recombinant P450 enzymes, hepatocytes, liver microsomes, as well as blood of rats dosed with SCO-267 at 10 mg/kg (mpk) ( Zhu et al, 2022 ).…”