Demethylzeylasteral exhibits strong inhibition towards UDP-glucuronosyltransferase (UGT) 1A6 and 2B7

Identification of an antitumor effect of demethylzeylasteral on human gastric cancer cells

Gastric cancer is a common malignancy in China, with the second highest mortality rate worldwide. Advanced gastric cancer usually exhibits a poor prognosis with a low 5-year survival rate. Therefore, developing novel drugs for the treatment of this cancer will be beneficial for patients. Demethylzeylasteral, an extract of tripterygium wilfordii, has shown positive anticancer activities. However, the possible antitumor effect of demethylzeylasteral on gastric cancer cells and its underlying molecular mechanism remain to be determined. In the present study, the Cell Counting Kit-8 and colony formation assays revealed that demethylzeylasteral impeded the proliferation of human gastric cancer cells in a dose-dependent manner. Furthermore, the Transwell assay identified an inhibitory effect of demethylzeylasteral on the migration of MKN-45 cells, while flow cytometry found that treatment with demethylzeylasteral induced apoptosis and decreased the mitochondrial membrane potential in the cancer cells. Further investigation revealed that demethylzeylasteral downregulated the phosphorylation of ERK1/2, AKT, and GSK-3β in MKN-45 cells. Notably, decreased expression of Bcl-2 and increased expression of Bax, cleaved caspase-3, cleaved caspase-9 and cleaved PARP were detected in the cancer cells treated with demethylzeylasteral. The present study demonstrated that demethylzeylasteral exhibits therapeutic potential for gastric cancer.

SOX1 promotes differentiation of nasopharyngeal carcinoma cells by activating retinoid metabolic pathway

Undifferentiation is a key feature of nasopharyngeal carcinoma (NPC), which presents as a unique opportunity for intervention by differentiation therapy. In this study, we found that SOX1 inhibited proliferation, promoted differentiation, and induced senescence of NPC cells, which depended on its transcriptional function. RNA-Seq-profiling analysis showed that multiple undifferentiated markers of keratin family, including KRT5, KRT13, and KRT19, were reduced in SOX1 overexpressed NPC cells. Interestingly, gene ontology (GO) analysis revealed genes in SOX1 overexpressed cells were enriched in extracellular functions. The data of LC/MS untargeted metabolomics showed that the content of retinoids in SOX1 overexpressed cells and culture medium was both higher than that in the control group. Subsequently, we screened mRNA level of genes in retinoic acid (RA) signaling or metabolic pathway and found that the expression of UDP-glucuronosyltransferases was significantly decreased. Furtherly, UGT2B7 could rescue the differentiation induced by SOX1 overexpression. Inhibition of UGTs by demethylzeylasteral (T-96) could mimic SOX1 to promote the differentiation of NPC cells. Thus, we described a mechanism by which SOX1 regulated the differentiation of NPC cells by activating retinoid metabolic pathway, providing a potential target for differentiation therapy of NPC.

Network Pharmacology-Based Prediction and Verification of Qingluo Tongbi Formula to Reduce Liver Toxicity of Tripterygium wilfordii via UGT2B7 in Endoplasmic Reticulum

Background

The hepatotoxicity of Tripterygium wilfordii Hook. f. (TWHF) limits its clinic utilization. Qingluo Tongbi formula (QTF) was formulated based on a basic Chinese medicine theory. Previous studies have confirmed the safety and efficacy of QTF in treating rheumatoid arthritis. Therefore, we considered that TWHF could be detoxified based on its reasonable compatibility with QTF. We investigated the detoxicity mechanism of QTF in reducing the liver toxicity of TWHF.

Material/Methods

We used network pharmacology to determine the relevant metabolism targets of TWHF, focusing on the phase II metabolic enzymes uridine diphosphate-glucuronosyltransferase 1A1 (UGT1A1), UGT1A6, and UGT2B7. Based on the molecular mechanisms of these predictions and the results of the network analysis, we designed experiments to verify our hypothesis in vivo. We used western blotting, real-time quantitative polymerase chain reaction (RT-qPCR), double immunofluorescence, and laser confocal microscopy to detect the expression of UGTs. Finally, we used transmission electron microscopy to observe the endoplasmic reticulum structure.

Results

The results confirmed that QTF reversed the TWHF-induced reduction of UGT content in liver microsomes, upregulated UGT1A1 and UGT1A6 but not UGT2B7 in the liver tissue. UGT2B7 expression in the liver and liver microsomes was inconsistent. QTF upregulated the expression of UGT2B7 in the endoplasmic reticulum, and QTF upregulated UGT2B7 expression levels in the endoplasmic reticulum compared with TWHF, which reduced liver toxicity. Structural changes were observed in the endoplasmic reticulum.

Conclusions

The Chinese traditional medicine compound QTF can achieve the effect of detoxification by upregulating the expression of UGT2B7 in the endoplasmic reticulum.

Demethylzeylasteral (T-96) inhibits triple-negative breast cancer invasion by blocking the canonical and non-canonical TGF-β signaling pathways

Inflammation is one of the characteristic features during the development of human tumors. A pro-inflammatory cytokine that is known to promote inflammation during cancer development is the transforming growth factor-β (TGF-β). On the other hand, demethylzeylasteral (T-96) is a natural compound isolated from Tripterygium wilfordii Hook F, which has been reported to have various pharmacological properties including anti-inflammatory and immunosuppressive activities. We investigated the effects of T-96 on the highly metastatic breast cancer cell line, MDA-MB-231. Cell migration was assessed by scratch-wound migration assay, and the molecular mechanisms underlying the effects of T-96 were examined by qPCR and Western blot analyses. We also investigated the suppression effects of T-96 on the pulmonary metastasis in the 4T1 mouse model. T-96 inhibited TGF-β-induced migration and epithelial-mesenchymal transition both in vitro and in vivo. These results demonstrate that T-96 inhibited invasion of MDA-MB-231 and 4T1 cells via suppressing the canonical and non-canonical TGF-β signaling pathways.

An LC-MS/MS method for quantification of demethylzeylasteral, a novel immunosuppressive agent in rat plasma and the application to a pharmacokinetic study

In this study, a sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the quantification of demethylzeylasteral in rat plasma. Electrospray ionization was operated in the negative ion mode while demethylzeylasteral and oleanolic acid (internal standard) were measured by selected reaction monitoring (demethylzeylasteral: m/z 479.2 → 436.0; oleanolic acid: m/z 454.9 → 407.2). This LC-MS/MS method had good selectivity, sensitivity, accuracy and precision. The pharmacokinetic profiles of demethylzeylasteral were subsequently examined in Wistar rats after oral or intravenous administration.

Friedelane triterpenoids: transformations toward A-ring modifications including 2-homoderivatives

Common reaction strategies were employed on suitable substrates to achieve a series of C2,C3-; C3,C4- and C2,C3,C4-functionalized (including 2-homo-) friedelane triterpenoids with just one to four efficient steps.

Demethylzeylasteral inhibits cell proliferation and induces apoptosis through suppressing MCL1 in melanoma cells

Demethylzeylasteral is one of the extracts of Tripterygium wilfordii Hook F, which plays important roles in multiple biological processes such as inflammation inhibition, as well as immunosuppression. However, anti-cancer function and the underlying mechanisms of demethylzeylasteral in melanoma cells remain unclear. In this study, we demonstrate that demethylzeylasteral has an anti-tumor property in melanoma cells. Demethylzeylasteral not only inhibits cell proliferation through cell cycle arrest at S phase, but also induces cell apoptosis in melanoma cells. MCL1 is an anti-apoptotic protein in BCL2 family, and amplifies frequently in multiple human cancers. MCL1 is also known as a potential contributor for the resistance of BCL2 inhibitors, as well as various chemotherapeutic drugs. MCL1 is, therefore, regarded as a potential target for cancer therapy. Here, for the first time, we unveil that demethylzeylasteral suppresses the expression of MCL1. Interestingly, MCL1 interacts with S phase-related protein CDK2, and thereby inhibits it’s ubiquitin-dependent degradation. Together, demethylzeylasteral is a promising anti-tumor compound in melanoma cells. Demethylzeylasteral is also a potential inhibitor of MCL1.

Validated assay for the evaluation of multiple glucuronidation activities in human liver microsomes via liquid chromatography-tandem mass spectrometry

A faster and more accurate LC-MS/MS method was established for the activity determination of multiple UGT isoforms in HLMs.