Evaluation of potential hepatotoxicity, a detailed knowledge of plasma proteins in physiological and pathological states, and identification of biomarkers and effective interventions can all contribute to initial drug development, discovery of molecular markers and drug targets, and early diagnosis and treatment of numerous diseases. To this end, researchers have published three insightful articles in JPA that further our knowledge of drug and endogenous metabolites, pharmacodynamic biomarkers, and potential remedies for treating complex diseases including cancer.
The first study explores drug-induced hepatotoxicity. It is routinely assessed during drug screening, which involves the use of two-dimensional (2D) monolayers of hepatocytes. However, experiments based on 2D monolayers are unable to accurately mimic the physiology and environment of liver cells. This study reports the development of a new method for detecting drug-induced hepatotoxicity using 3D cell cultures and ambient mass spectrometry imaging. This article was available online on 14 April 2023 and was published in Volume 13 Issue 5 of the Journal of Pharmaceutical Analysis in May 2023.
Author Ruiping Zhang explains, "3D cell spheroid models, in association with mass spectrometry imaging (MSI), enable the investigation of in vivo-like biological processes under various physiological and pathological conditions. In this study, we coupled airflow-assisted desorption electrospray ionization-MSI (AFADESI-MSI) with 3D HepG2 spheroids to assess the metabolism and hepatotoxicity of amiodarone (AMI)."
AMI, a widely used antiarrhythmic drug, can cause liver injury. Although multiple studies show that AMI metabolism plays a key role in drug-induced hepatotoxicity, the underlying molecular mechanisms remain elusive. The current study used AMI as a model drug and examined its likely metabolic action inside the liver using 3D HepG2 spheroids. The newly devised method achieved high-coverage imaging of more than 1,100 endogenous metabolites. Treatment of the 3D HepG2 spheroids with AMI at different time points resulted in the production of 15 AMI metabolites involved in N-desethylation, hydroxylation, deiodination, and desaturation metabolic reactions. Based on their spatiotemporal dynamics features, the authors proposed metabolic pathways of AMI inside liver cells.
The research team identified the dysregulated metabolisms of arachidonic acid and glycerophospholipid, indicative of the AMI hepatotoxicity mechanism. Lastly, they constructed a biomarker group of eight fatty acids that exhibited improved correlation to cell viability.
"This work exemplifies a new method for the screening and discovery of hepatotoxicity biomarkers and can be used for the early evaluation of drugs," comments Zeper Abliz, one of the corresponding authors.
The second study published in this journal focuses on the proteomic characterization of plasma. Researchers show how NaY, a newly synthesized zeolite, adsorbs and traps proteins from blood plasma, thus forming a protein corona or layer. As a result, it masks the effect caused by high-abundance proteins during liquid chromatography-tandem mass spectrometry. Author Jin Zhao observes, "Our study data clearly indicate that NaY can help identify and quantify nearly 4,000 plasma proteins, including those in low abundance, with extreme sensitivity of up to pg/mL." Quite interestingly, a pilot study based on the plasma samples obtained from 30 patients with lung adenocarcinoma and 15 healthy subjects shows that the NaY-based technique is able to accurately differentiate affected patients from healthy subjects via plasma protein detection, offering a tool for exploring plasma proteomics and its translation applications.
The third study published in JPA focuses on the potential treatment of hepatocellular carcinoma (HCC), the third leading cause of cancer-related deaths globally. The authors of this study investigated the anti-HCC efficacy and mechanisms of ginsenoside Rk3, a rare saponin found in heat-treated ginseng roots. According to both in vitro HepG2 and HCC-LM3 cell-based studies and in vivo experiments on primary live cancer mice and HCC-LM3 subcutaneous tumor-bearing mice, Rk3 blocked the cell cycle in HCC in the G1 phase, inducing autophagy and apoptosis. Says Daidi Fan, an author of the study, "Our results indicate that Rk3 works by binding to PI3K/AKT, proteins often implicated in various cancers including HCC, and regulates their pathway to inhibit HCC growth." Although clinical validation seems necessary, this finding does have major implications for HCC and strongly suggests ginsenoside Rk3 as a novel therapeutic agent for HCC with low toxic side effects.
These studies are welcome additions to our ever-expanding repertoire of drug and disease knowledge!
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Reference
DOI: https://doi.org/10.1016/j.jpha.2023.04.007
Authors: Limei Lia, Qingce Zanga, Xinzhu Lia, Ying Zhua, Shanjing Wena, Jiuming Hea, Ruiping Zhanga, Zeper Abliza,b,c
Affiliations:
aState Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, China
bKey Laboratory of Mass Spectrometry Imaging and Metabolomics (Minzu University of China), National Ethnic Affairs Commission, Beijing, 100081, China
cCenter for Imaging and Systems Biology, College of Life and Environmental Sciences, Minzu University of China, Beijing, 100081, China
