Integrating Network Pharmacology with in vitro Experiments to Validate the Efficacy of Celastrol Against Hepatocellular Carcinoma Through Ferroptosis.

Background: As a traditional Chinese medicine monomer derived from Tripterygium wilfordii Hook.f. with potential anticancer activity, celastrol can induce ferroptosis in hepatic stellate cells and inhibit their activation to alleviate liver fibrosis. Activation of ferroptosis can effectively inhibit Hepatocellular carcinoma (HCC). Whether celastrol inhibits HCC by inducing ferroptosis remains to be studied. Purpose: To explore the potential targets of celastrol against HCC through ferroptosis based on network pharmacology and to verify the anticancer effect of celastrol on HepG2 cells. Methods: We collected celastrol targets, HCC, and ferroptosis-related genes through online databases, and got their intersection targets. Subsequently, we obtained a protein-protein interaction (PPI) network, and performed gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis to gain key genes for further study. They were verified in vitro and were performed molecular docking. The changes in cell proliferation and ferroptosis characteristics of HepG2 cells after celastrol treatment were detected. Results: 31 core target genes were screened for PPI network and enrichment analysis. The most significantly related KEGG pathway was chemical carcinogenesis-reactive oxygen species. The mRNA and protein levels of GSTM1 were significantly decreased after celastrol treatment. Molecular docking demonstrated the interaction between celastrol and GSTM1. Ferroptosis was induced and cell proliferation was inhibited by celastrol in HCC cells. Conclusion: Celastrol induces ferroptosis in HCC via regulating GSTM1 expression and may serve as a novel therapeutic compound with clinical potential in HCC treatment.

Celastrol induces ferroptosis by suppressing RRM2 in hepatocellular carcinoma.

Introduction and Objectives: Ferroptosis is a novel form of cell death driven by iron dependence and lipid peroxidation, presenting a promising potential as an innovative strategy for cancer treatment. Celastrol (Cel) is particularly effective in inducing ferroptosis, but its molecular mechanism remains unclear. The study aims to elucidate the potential mechanism through both in vitro and in vivo experiments. Materials and methods: CCK-8 assay, Western blot analysis and measurements of reactive oxygen species (ROS), malondialdehyde (MDA), and glutathione (GSH) were performed to investigate how Cel inhibits the proliferation of hepatocellular carcinoma (HCC) cells via the ferroptosis mechanism. Bioinformatics analysis based on the TCGA-LIHC and FerrDb databases was performed to identify the target gene RRM2, and molecular docking-simulated binding between RRM2 and Cel. The role of RRM2 in the effects of Cel was determined through lentiviral transfection, Transwell assays, and in vivo experiments. Results: Cel inhibited HCC cell proliferation via the ferroptosis pathway. Inhibition RRM2 significantly reduces mTOR protein phosphorylation, while overexpressing RRM2 can attenuate theeffects of Cel on the proliferation, migration, invasion, and ferroptosis induction of HCC cells. The result of in vivo experiments in nude mice demonstrated that Cel inhibited tumor growth without adversely affecting liver and kidney function indicators. Immunohistochemistry and Western blot analyses revealed that Cel activated the key proteins in the ferroptosis pathway and affected crucial indicators such as malondialdehyde (MDA) and glutathione (GSH). Conclusion: In this study, we clarifiy the molecular mechanism of Cel, thus broadening its clinical applications for treating various cancer types, including liver cancer.

Ferroptosis inhibitors reduce celastrol toxicity and preserve its insulin sensitizing effects in insulin resistant HepG2 cells.

OBJECTIVE: Research has shown that celastrol can effectively treat a variety of diseases, yet when passing a certain dosage threshold, celastrol becomes toxic, causing complications such as liver and kidney damage and erythrocytopenia, among others. With this dichotomy in mind, it is extremely important to find ways to preserve celastrol's efficacy while reducing or preventing its toxicity. METHODS: In this study, insulin-resistant HepG2 (IR-HepG2) cells were prepared using palmitic acid and used for in vitro experiments. IR-HepG2 cells were treated with celastrol alone or in combination with N-acetylcysteine (NAC) or ferrostatin-1 (Fer-1) for 12, 24 or 48 h, at a range of doses. Cell counting kit-8 assay, Western blotting, quantitative reverse transcription-polymerase chain reaction, glucose consumption assessment, and flow cytometry were performed to measure celastrol's cytotoxicity and whether the cell death was linked to ferroptosis. RESULTS: Celastrol treatment increased lipid oxidation and decreased expression of anti-ferroptosis proteins in IR-HepG2 cells. Celastrol downregulated glutathione peroxidase 4 (GPX4) mRNA. Molecular docking models predicted that solute carrier family 7 member 11 (SLC7A11) and GPX4 were covalently bound by celastrol. Importantly, we found for the first time that the application of ferroptosis inhibitors (especially NAC) was able to reduce celastrol's toxicity while preserving its ability to improve insulin sensitivity in IR-HepG2 cells. CONCLUSION: One potential mechanism of celastrol's cytotoxicity is the induction of ferroptosis, which can be alleviated by treatment with ferroptosis inhibitors. These findings provide a new strategy to block celastrol's toxicity while preserving its therapeutic effects. Please cite this article as: Liu JJ, Zhang X, Qi MM, Chi YB, Cai BL, Peng B, Zhang DH. Ferroptosis inhibitors reduce celastrol toxicity and preserve its insulin sensitizing effects in insulin resistant HepG2 cells. J Integr Med. 2024; 22(3): 286-294.

Hyperglycemia exacerbates cerebral ischemia/reperfusion injury by up-regulating autophagy through p53-Sesn2-AMPK pathway.

Hyperglycemia exacerbates ischemic brain injury by up-regulating autophagy. However, the underlying mechanisms are unknown. This study aims to determine whether hyperglycemia activates autophagy through the p53-Sesn2-AMPK signaling pathway. Rats were subjected to 30-min middle cerebral artery occlusion (MCAO) with reperfusion for 1- and 3-day under normo- and hyperglycemic conditions; and HT22 cells were exposed to oxygen deprivation (OG) or oxygen-glucose deprivation and re-oxygenation (OGD/R) with high glucose. Autophagy inhibitors, 3-MA and ARI, were used both in vivo and in vitro. The results showed that, compared with the normoglycemia group (NG), hyperglycemia (HG) increased infarct volume and apoptosis in penumbra area, worsened neurological deficit, and augmented autophagy. after MCAO followed by 1-day reperfusion. Further, HG promoted the conversion of LC-3I to LC-3II, decreased p62, increased protein levels of aldose reductase, p53, P-p53ser15, Sesn2, AMPK and numbers of autophagosomes and autolysosomes, detected by transmission electron microscopy and mRFP-GFP-LC3 molecular probe, in the cerebral cortex after ischemia and reperfusion injury in animals or in cultured HT22 cells exposed to hypoxia with high glucose content. Finally, experiments with autophagy inhibitors 3-MA and aldose reductase inhibitor (ARI) revealed that while both inhibitors reduced the number of TUNEL positive neurons and reversed the effects of hyperglycemic ischemia on LC3 and p62, only ARI decreased the levels of p53, P-p53ser15. These results suggested that hyperglycemia might induce excessive autophagy to aggravate the brain injury resulted from I/R and that hyperglycemia might activate the p53-Sesn2-AMPK signaling pathway, in addition to the classical PI3K/AKT/mTOR autophagy pathway.

Norwegian scabies in a patient treated with Tripterygium glycoside for rheumatoid arthritis

Abstract: We report an 80-year-old male patient with severe rheumatoid arthritis who was treated with tripterygium glycoside, an immunosuppressive agent made from the extract of a Chinese medicinal herb called Tripterygium wilfordii Hook F. The patient had no apparent skin lesions before the treatment, but he developed aggressive hyperkeratotic lesions with rapid progression after using tripterygium glycoside. He was repeatedly diagnosed with eczema, but treatment failed to achieve efficacy. Interestingly, a microscopic examination of the lesions revealed numerous scabies mites and eggs. Thus, we confirmed the diagnosis of Norwegian scabies infection. Treated with crotamiton 10% cream and 10% sulfur ointment for one month, the patient's clinical symptoms disappeared.