A high-throughput cell-based gaussia luciferase reporter assay for measurement of CYP1A1, CYP2B6, and CYP3A4 induction

The Function of Xenobiotic Receptors in Metabolic Diseases

Metabolic diseases are a series of metabolic disorders that include obesity, diabetes, insulin resistance, hypertension, and hyperlipidemia. The increased prevalence of metabolic diseases has resulted in higher mortality and mobility rates over the past decades, and this has led to extensive research focusing on the underlying mechanisms. Xenobiotic receptors (XRs) are a series of xenobiotic-sensing nuclear receptors that regulate their downstream target genes expression, thus defending the body from xenobiotic and endotoxin attacks. XR activation is associated with the development of a number of metabolic diseases such as obesity, nonalcoholic fatty liver disease, type 2 diabetes, and cardiovascular diseases, thus suggesting an important role for XRs in modulating metabolic diseases. However, the regulatory mechanism of XRs in the context of metabolic disorders under different nutrient conditions is complex and remains controversial. This review summarizes the effects of XRs on different metabolic components (cholesterol, lipids, glucose, and bile acids) in different tissues during metabolic diseases. As chronic inflammation plays a critical role in the initiation and progression of metabolic diseases, we also discuss the impact of XRs on inflammation to comprehensively recognize the role of XRs in metabolic diseases. This will provide new ideas for treating metabolic diseases by targeting XRs. SIGNIFICANCE STATEMENT: This review outlines the current understanding of xenobiotic receptors on nutrient metabolism and inflammation during metabolic diseases. This work also highlights the gaps in this field, which can be used to direct the future investigations on metabolic diseases treatment by targeting xenobiotic receptors.

Ginsenoside Rg1 protects mice against 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced liver injury by inhibiting CYP1A1 through the aryl hydrocarbon receptor

ETHNOPHARMACOLOGICAL RELEVANCE

Panax ginseng C. A. Meyer (ginseng) is a widely used traditional Chinese medicine that has played a beneficial role in the treatment of various diseases, including liver diseases. Ginsenoside Rg1 is a saponin isolated and purified from ginseng that exerts protective effects on the liver in some liver injury models. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is a ubiquitous dioxin found mostly in food products that causes liver injury and other human diseases. Although significant efforts have been made to reduce the burden of liver disease, there is still a lack of effective treatment methods.

AIM OF THE STUDY

Although ginsenoside Rg1 was reported to inhibit TCDD-mediated cytochrome P450 1A1 (CYP1A1) induction in HepG2 cells, we sought to verify its hepatoprotective effects and elucidate its mechanism in a TCDD-induced liver injury model in mice.

MATERIAL AND METHODS

The mouse liver injury model was established by intraperitoneal TCDD injection, followed by treatment with various doses of ginsenoside Rg1 (50, 100, and 200 mg/kg). Clinical indicators of liver injury, such as an increase in serum aspartate aminotransferase and alanine aminotransferase levels, as well as histopathological changes were evaluated.

RESULTS

The common clinical indicators of liver injury were detected following TCDD injection, including an increase in serum alanine aminotransferase and aspartate aminotransferase levels, increased relative liver weight, and histopathological changes. Following treatment with ginsenoside Rg1, the levels of aspartate aminotransferase and alanine aminotransferase decreased significantly, and the liver histology was improved. In addition, ginsenoside Rg1 competitively inhibited TCDD-induced Cyp1a1 mRNA transcription through the modulation of aryl hydrocarbon receptor (AhR) nuclear translocation.

CONCLUSION

Ginsenoside Rg1 is a potent partial AhR agonist that has potential as an effective medication for protecting against TCDD-associated liver injury.

Hsa-miR-4277 Decelerates the Metabolism or Clearance of Sorafenib in HCC Cells and Enhances the Sensitivity of HCC Cells to Sorafenib by Targeting cyp3a4

Increasing evidence has shown that the metabolism and clearance of molecular targeted agents, such as sorafenib, plays an important role in mediating the resistance of HCC cells to these agents. Metabolism of sorafenib is performed by oxidative metabolism, which is initially mediated by CYP3A4. Thus, targeting CYP3A4 is a promising approach to enhance the sensitivity of HCC cells to chemotherapeutic agents. In the present work, we examined the association between CYP3A4 and the prognosis of HCC patients receiving sorafenib. Using the online tool miRDB, we predicted that has-microRNA-4277 (miR-4277), an online miRNA targets the 3’UTR of the transcript of cyp3a4. Furthermore, overexpression of miR-4277 in HCC cells repressed the expression of CYP3A4 and reduced the elimination of sorafenib in HCC cells. Moreover, miR-4277 enhanced the sensitivity of HCC cells to sorafenib in vitro and in vivo. Therefore, our results not only expand our understanding of CYP3A4 regulation in HCC, but also provide evidence for the use of miR-4277 as a potential therapeutic in advanced HCC.