Uncovering SOD3 and GPX4 as new targets of Benzo[α]pyrene-induced hepatotoxicity through Metabolomics and Chemical Proteomics.

Benzo[α]pyrene (Bap) is recognized as a ubiquitous environmental pollutant among the polycyclic aromatic hydrocarbons (PAHs) class. Previous studies have shown that the hepatotoxicity of Bap is mainly caused by its metabolites, although it remains unclear whether Bap itself induces such damage. This study integrated metabolomics and chemical proteomics approaches to comprehensively identify the potential target proteins affected by Bap in liver cells. The results from the metabolomics showed that the significant changed metabolites were related with cellular redox homeostasis. CEllular Thermal Shift Assay (CETSA) showed that Bap induced protein thermal displacement of superoxide dismutase 3 (SOD3) and glutathione peroxidase 4 (GPX4), which are closely related to oxidative homeostasis. Further validation through in vitro CETSA and drug affinity response target stability (DARTS) revealed that Bap directly affected the stability of SOD3 and GPX4 proteins. The binding affinities of Bap to the potential target proteins were further evaluated using molecular docking, while the isothermal titration calorimetry (ITC) interaction measurements indicated nanomolar-level Kd values. Importantly, we found that Bap weakened the antioxidant capacity by destroying the activities of SOD3 and GPX4, which provided a new understanding of the mechanism of hepatotoxicity induced by Bap. Moreover, our provided workflow integrating metabolomics and label-free chemical proteomics, can be regarded as a practical way to identify the targets and inter-mechanisms for the various environmental compounds.

A Q-marker screening strategy based on ADME studies and systems biology for Chinese herbal medicine, taking Qianghuo Shengshi decoction in treating rheumatoid arthritis as an example.

Chinese herbal medicine (CHM) exhibits a broad spectrum of clinical applications and demonstrates favorable therapeutic efficacy. Nonetheless, elucidating the underlying mechanism of action (MOA) of CHM in disease treatment remains a formidable task due to its inherent characteristics of multi-level, multi-linked, and multi-dimensional non-linear synergistic actions. In recent years, the concept of a Quality marker (Q-marker) proposed by Liu et al. has significantly contributed to the monitoring and evaluation of CHM products, thereby fostering the advancement of CHM research. Within this study, a Q-marker screening strategy for CHM formulas has been introduced, particularly emphasising efficacy and biological activities, integrating absorption, distribution, metabolism, and excretion (ADME) studies, systems biology, and experimental verification. As an illustrative case, the Q-marker screening of Qianghuo Shengshi decoction (QHSSD) for treating rheumatoid arthritis (RA) has been conducted. Consequently, from a pool of 159 compounds within QHSSD, five Q-markers exhibiting significant in vitro anti-inflammatory effects have been identified. These Q-markers encompass notopterol, isoliquiritin, imperatorin, cimifugin, and glycyrrhizic acid. Furthermore, by employing an integrated analysis of network pharmacology and metabolomics, several instructive insights into pharmacological mechanisms have been gleaned. This includes the identification of key targets and pathways through which QHSSD exerts its crucial roles in the treatment of RA. Notably, the inhibitory effect of QHSSD on AKT1 and MAPK3 activation has been validated through western blot analysis, underscoring its potential to mitigate RA-related inflammatory responses. In summary, this research demonstrates the proposed strategy's feasibility and provides a practical reference model for the systematic investigation of CHM formulas.

Network pharmacology and metabolomics elucidate the underlying mechanisms of Venenum Bufonis in the treatment of colorectal cancer.

ETHNOPHARMACOLOGICAL RELEVANCE: The present study aims to evaluate the efficacy of Venenum Bufonis (VBF), a traditional Chinese medicine derived from the dried secretions of the Chinese toad, in treating colorectal cancer (CRC). The comprehensive roles of VBF in CRC through systems biology and metabolomics approaches have been rarely investigated. AIMS OF THE STUDY: The study sought to uncover the potential underlying mechanisms of VBF's anti-cancer effects by investigating the impact of VBF on cellular metabolic balance. MATERIALS AND METHODS: An integrative approach combining biological network analysis, molecular docking and multi-dose metabolomics was used to predict the effects and mechanisms of VBF in CRC treatment. The prediction was verified by cell viability assay, EdU assay and flow cytometry. RESULTS: The results of the study indicate that VBF presents anti-CRC effects and impacts cellular metabolic balance through its impact on cell cycle-regulating proteins, such as MTOR, CDK1, and TOP2A. The results of the multi-dose metabolomics analysis suggest a dose-dependent reduction of metabolites related to DNA synthesis after VBF treatment, while the EdU and flow cytometry results indicate that VBF inhibits cell proliferation and arrests the cell cycle at the S and G2/M phases. CONCLUSIONS: These findings suggest that VBF disrupts purine and pyrimidine pathways in CRC cancer cells, leading to cell cycle arrest. This proposed workflow integrating molecular docking, multi-dose metabolomics, and biological validation, which contented EdU assay, cell cycle assay, provides a valuable framework for future similar studies.

PKM2-mediated neuronal hyperglycolysis enhances the risk of Parkinson's disease in diabetic rats.

Epidemiological and animal studies indicate that pre-existing diabetes increases the risk of Parkinson's disease (PD). However, the mechanisms underlying this association remain unclear. In the present study, we found that high glucose (HG) levels in the cerebrospinal fluid (CSF) of diabetic rats might enhance the effect of a subthreshold dose of the neurotoxin 6-hydroxydopamine (6-OHDA) on the development of motor disorders, and the damage to the nigrostriatal dopaminergic neuronal pathway. In vitro, HG promoted the 6-OHDA-induced apoptosis in PC12 cells differentiated to neurons with nerve growth factor (NGF) (NGF-PC12). Metabolomics showed that HG promoted hyperglycolysis in neurons and impaired tricarboxylic acid cycle (TCA cycle) activity, which was closely related to abnormal mitochondrial fusion, thus resulting in mitochondrial loss. Interestingly, HG-induced upregulation of pyruvate kinase M2 (PKM2) combined with 6-OHDA exposure not only mediated glycolysis but also promoted abnormal mitochondrial fusion by upregulating the expression of MFN2 in NGF-PC12 cells. In addition, we found that PKM2 knockdown rescued the abnormal mitochondrial fusion and cell apoptosis induced by HG+6-OHDA. Furthermore, we found that shikonin (SK), an inhibitor of PKM2, restored the mitochondrial number, promoted TCA cycle activity, reversed hyperglycolysis, enhanced the tolerance of cultured neurons to 6-OHDA, and reduced the risk of PD in diabetic rats. Overall, our results indicate that diabetes promotes hyperglycolysis and abnormal mitochondrial fusion in neurons through the upregulation of PKM2, leading to an increase in the vulnerability of dopaminergic neurons to 6-OHDA. Thus, the inhibition of PKM2 and restoration of mitochondrial metabolic homeostasis/pathways may prevent the occurrence and development of diabetic PD.

Exploring the Absorption Mechanisms of Imidazolium-Based Ionic Liquids to Epigallocatechin Gallate.

Imidazolium-based ionic liquids are wildly used in natural product adsorption and purification. In this work, one typical polymeric ionic liquid (PIL) was synthesized by using L-proline as the anion, which exhibited excellent adsorption capacity toward tea polyphenol epigallocatechin gallate (EGCG). The adsorption conditions were optimized with the response surface method (RSM). Under the optimum conditions, the adsorption capacity of the PIL for EGCG can reach as high as 552 mg/g. Dynamics and isothermal research shows that the adsorption process of EGCG by the PIL particularly meets the quasi-second-order kinetic equation and monolayer adsorption mechanism. According to thermodynamic parameter analysis, the adsorption process is endothermic and spontaneous. The results of theoretical calculation by molecular docking also demonstrated the interaction mechanisms between EGCG and the ionic liquid. Considering the wide application of imidazolium-based ionic liquids in component adsorption and purification, the present study can not only be extended to other similar experimental mechanism validation, but also be representative for guiding the synthesis of PIL and optimization of adsorption conditions.