Geometric Isomer of Guanabenz Confers Hepatoprotection to a Murine Model of Acetaminophen Toxicity

The environmental risk of heterogeneous oxidation is unneglectable: Time-resolved assessments beyond typical intermediate investigation

The safety of advanced oxidation processes is paramount, surpassing treatment efficiency concerns. However, current research is limited to the qualitative toxicity investigations of targeted contaminants by-products, while the detoxification effects of heterogeneous advanced oxidation processes are largely unknown. Here we propose an environmental risk assessment that distinguishes between preferred oxidation pathways of the detoxification effects, thereby selecting the most suitable treatment system for each contaminant. Through environmental risk analyses based on the by-product quantification, >40 % of previously overlooked toxicity has been rediscovered, significantly improving the accuracy of contaminant detoxification evaluation. The by-products contributed risk mostly reached the maximum after 30 min of reaction, evenly distributed on aquatic indicators but largely originated from on radical oxidation pathways. Density functional theory is applied to determine the generation probability of isomers, and deep neural network regression modelling accelerated derivation on structural transformation of toxic molecules. Furthermore, an evaluation system is established using risk quotients and cluster analysis classification modelling, enabling the quantitative cross-comparison in oxidation systems. This approach enhances the understanding of the safety and efficiency within oxidation processes, introducing various new methods supporting quantitative environmental risk assessment of emerging contaminant degradation in complicated heterogeneous oxidation processes. SYNOPSIS: The environmental risks in advanced oxidation processes are quantified by deep learning and theoretical chemistry-assisted assessments.

Deletion of Glyoxalase 1 exacerbates acetaminophen-induced hepatotoxicity in mice

Acetaminophen (APAP) overdose triggers a cascade of intracellular oxidative stress events culminating in acute liver injury. The clinically used antidote, N-acetylcysteine (NAC) has a narrow therapeutic window and early treatment is essential for satisfactory therapeutic outcome. For more versatile therapies that can be effective even at late-presentation, the intricacies of APAP-induced hepatotoxicity must be better understood. Accumulation of advanced glycation end-products (AGEs) and consequent activation of the receptor for AGEs (RAGE) are considered one of the key mechanistic features of APAP toxicity. Glyoxalase-1 (Glo-1) regulates AGE formation by limiting the levels of methylglyoxal (MEG). In this study, we studied the relevance of Glo-1 in APAP mediated activation of RAGE and downstream cell-death cascades. Constitutive Glo-1 knockout mice (GKO) and a cofactor of Glo-1, ψ-GSH, were employed as tools. Our findings show elevated oxidative stress, activation of RAGE and hepatocyte necrosis through steatosis in GKO mice treated with high-dose APAP compared to wild type controls. A unique feature of the hepatic necrosis in GKO mice is the appearance of microvesicular steatosis as a result of centrilobular necrosis, rather than inflammation seen in wild type. The GSH surrogate and general antioxidant, ψ-GSH alleviated APAP toxicity irrespective of Glo-1 status, suggesting that oxidative stress being the primary driver of APAP toxicity. Overall, exacerbation of APAP hepatotoxicity in GKO mice suggests the importance of this enzyme system in antioxidant defense against initial stages of APAP overdose.