Xenobiotic receptors in mediating the effect of sepsis on drug metabolism

Complementary and alternative medicine on cognitive defects and neuroinflammation after sepsis

Sepsis-associated encephalopathy (SAE) is a common manifestation of sepsis, ranging from mild confusion and delirium to severe cognitive impairment and deep coma. SAE is associated with higher mortality and long-term outcomes, particularly substantial declines in cognitive function. The mechanisms of SAE probably include neuroinflammation that is mediated by systemic inflammation and ischemic lesions in the brain, a disrupted blood-brain barrier, oxidative stress, neurotransmitter dysfunction, and severe microglial activation. Increasing evidence suggests that complementary and alternative medicine, especially Traditional Chinese Medicine (TCM), is favorable in alleviating cognitive decline after sepsis. Here, we summarized the studies of traditional herbal remedies, TCM formulas and acupuncture therapy in animal models of neurological dysfunctions after sepsis in recent decades and reviewed their potential mechanisms.

The Role of Iron Metabolism in Sepsis-associated Encephalopathy: a Potential Target

Sepsis-associated encephalopathy (SAE) is an acute cerebral dysfunction secondary to infection, and the severity can range from mild delirium to deep coma. Disorders of iron metabolism have been proven to play an important role in a variety of neurodegenerative diseases by inducing cell damage through iron accumulation in glial cells and neurons. Recent studies have found that iron accumulation is also a potential mechanism of SAE. Systemic inflammation can induce changes in the expression of transporters and receptors on cells, especially high expression of divalent metal transporter1 (DMT1) and low expression of ferroportin (Fpn) 1, which leads to iron accumulation in cells. Excessive free Fe2+ can participate in the Fenton reaction to produce reactive oxygen species (ROS) to directly damage cells or induce ferroptosis. As a result, it may be of great help to improve SAE by treatment of targeting disorders of iron metabolism. Therefore, it is important to review the current research progress on the mechanism of SAE based on iron metabolism disorders. In addition, we also briefly describe the current status of SAE and iron metabolism disorders and emphasize the therapeutic prospect of targeting iron accumulation as a treatment for SAE, especially iron chelator. Moreover, drug delivery and side effects can be improved with the development of nanotechnology. This work suggests that treating SAE based on disorders of iron metabolism will be a thriving field.

Pregnane X receptor as a therapeutic target for cholestatic liver injury

Cholestatic liver injury (CLI) is caused by toxic bile acids (BAs) accumulation in the liver and can lead to inflammation and liver fibrosis. The mechanisms underlying CLI development remain unclear, and this disease has no effective cure. However, regulating BA synthesis and homeostasis represents a promising therapeutic strategy for CLI treatment. Pregnane X receptor (PXR) plays an essential role in the metabolism of endobiotics and xenobiotics via the transcription of metabolic enzymes and transporters, which can ultimately modulate BA homeostasis and exert anticholestatic effects. Furthermore, recent studies have demonstrated that PXR exhibits antifibrotic and anti-inflammatory properties, providing novel insights into treating CLI. Meanwhile, several drugs have been identified as PXR agonists that improve CLI. Nevertheless, the precise role of PXR in CLI still needs to be fully understood. This review summarizes how PXR improves CLI by ameliorating cholestasis, inhibiting inflammation, and reducing fibrosis and discusses the progress of promising PXR agonists for treating CLI.

Panaxytriol upregulates CYP3A4 expression through the interaction between nuclear regulators and DNA response elements

ETHNOPHARMACOLOGICAL RELEVANCE

Cytochrome P3A4 (CYP3A4) is a crucial drug-metabolizing enzyme, and its expression is regulated by the pregnane X receptor (PXR), constitutive androstane receptor (CAR), steroid receptor coactivator 1 (SRC-1), and acetyltransferase P300. Panaxytriol is a naturally derived active substance extracted from the roots of Panax ginseng C. A. Mey. which is widely used clinically. Our previous studies have shown that panaxytriol induces CYP3A4 expression through PXR activation, which is antagonized by high CAR expression. However, the underlying mechanism remains unclear.

AIM OF THE STUDY

This study aimed to investigate the mechanism of panaxytriol in inducing CYP3A4 expression via interactions between nuclear regulators and DNA response elements.

MATERIALS AND METHODS

Immunoprecipitation technique was used to assess the binding levels of PXR and CAR with the coactivators SRC-1 and P300 in HepG2 and Huh-7 cells. Furthermore, chromatin immunoprecipitation assay was used to investigate the PXR and CAR interaction with the CYP3A4 promoter response element ER-6/DR-3.

RESULTS

The binding of PXR to SRC-1, P300, and the response elements ER-6 and DR-3 was improved with an increase in panaxytriol concentration (10-80 μM), and the binding affinity was further enhanced upon CAR silencing. The binding of CAR to SRC-1 and the response elements ER-6 and DR-3 was significantly higher at 80 μM panaxytriol, whereas no significant binding was observed between CAR and P300.

CONCLUSION

Panaxytriol promoted the recruitment of PXR to SRC-1 and P300, binding to ER-6 and DR-3, and upregulating CYP3A4 expression. Furthermore, an interactive dialogue regulatory mechanism between PXR and CAR was observed.

Role of Cytochrome P450 2C9 in COVID-19 Treatment: Current Status and Future Directions

The major human liver drug metabolising cytochrome P450 (CYP) enzymes are downregulated during inflammation and infectious disease state, especially during coronavirus disease 2019 (COVID-19) infection. The influx of proinflammatory cytokines, known as a 'cytokine storm', during severe COVID-19 leads to the downregulation of CYPs and triggers new cytokine release, which further dampens CYP expression. Impaired drug metabolism, along with the inevitable co-administration of drugs or 'combination therapy' in patients with COVID-19 with various comorbidities, could cause drug-drug interactions, thus worsening the disease condition. Genetic variability or polymorphism in CYP2C9 across different ethnicities could contribute to COVID-19 susceptibility. A number of drugs used in patients with COVID-19 are inducers or inhibitors of, or are metabolised by, CYP2C9, and co-administration might cause pharmacokinetic and pharmacodynamic interactions. It is also worth mentioning that some of the COVID-19 drug interactions are due to altered activity of other CYPs including CYP3A4. Isoniazid/rifampin for COVID-19 and tuberculosis co-infection; lopinavir/ritonavir and cobicistat/remdesivir combination therapy; or multi-drug therapy including ivermectin, azithromycin, montelukast and acetylsalicylic acid, known as TNR4 therapy, all improved recovery in patients with COVID-19. However, a combination of CYP2C9 inducers, inhibitors or both, and plausibly different CYP isoforms could lead to treatment failure, hepatotoxicity or serious side effects including thromboembolism or bleeding, as observed in the combined use of azithromycin/warfarin. Further, herbs that are CYP2C9 inducers and inhibitors, showed anti-COVID-19 properties, and in silico predictions postulated that phytochemical compounds could inhibit SARS-CoV-2 virus particles. COVID-19 vaccines elicit immune responses that activate cytokine release, which in turn suppresses CYP expression that could be the source of compromised CYP2C9 drug metabolism and the subsequent drug-drug interaction. Future studies are recommended to determine CYP regulation in COVID-19, while recognising the involvement of CYP2C9 and possibly utilising CYP2C9 as a target gene to tackle the ever-mutating SARS-CoV-2.

Pregnenolone Inhibits Doxorubicin-Induced Cardiac Oxidative Stress, Inflammation, and Apoptosis-Role of Matrix Metalloproteinase 2 and NADPH Oxidase 1

The clinical usefulness of doxorubicin (DOX) is limited by its serious adverse effects, such as cardiotoxicity. Pregnenolone demonstrated both anti-inflammatory and antioxidant activity in animal models. The current study aimed to investigate the cardioprotective potential of pregnenolone against DOX-induced cardiotoxicity. After acclimatization, male Wistar rats were randomly grouped into four groups: control (vehicle-treated), pregnenolone (35 mg/kg/d, p.o.), DOX (15 mg/kg, i.p, once), and pregnenolone + DOX. All treatments continued for seven consecutive days except DOX, which was administered once on day 5. The heart and serum samples were harvested one day after the last treatment for further assays. Pregnenolone ameliorated the DOX-induced increase in markers of cardiotoxicity, namely, histopathological changes and elevated serum levels of creatine kinase-MB and lactate dehydrogenase. Moreover, pregnenolone prevented DOX-induced oxidative changes (significantly lowered cardiac malondialdehyde, total nitrite/nitrate, and NADPH oxidase 1, and elevated reduced glutathione), tissue remodeling (significantly decreased matrix metalloproteinase 2), inflammation (significantly decreased tumor necrosis factor-α and interleukin 6), and proapoptotic changes (significantly lowered cleaved caspase-3). In conclusion, these findings show the cardioprotective effects of pregnenolone in DOX-treated rats. The cardioprotection achieved by pregnenolone treatment can be attributed to its antioxidant, anti-inflammatory, and antiapoptotic actions.

Altered intestinal microbiome and metabolome correspond to the clinical outcome of sepsis

BACKGROUND

The gut microbiome plays a pivotal role in the progression of sepsis. However, the specific mechanism of gut microbiota and its metabolites involved in the process of sepsis remains elusive, which limits its translational application.

METHOD

In this study, we used a combination of the microbiome and untargeted metabolomics to analyze stool samples from patients with sepsis enrolled at admission, then microbiota, metabolites, and potential signaling pathways that might play important roles in disease outcome were screened out. Finally, the above results were validated by the microbiome and transcriptomics analysis in an animal model of sepsis.

RESULTS

Patients with sepsis showed destruction of symbiotic flora and elevated abundance of Enterococcus, which were validated in animal experiments. Additionally, patients with a high burden of Bacteroides, especially B. vulgatus, had higher Acute Physiology and Chronic Health Evaluation II scores and longer stays in the intensive care unit. The intestinal transcriptome in CLP rats illustrated that Enterococcus and Bacteroides had divergent profiles of correlation with differentially expressed genes, indicating distinctly different roles for these bacteria in sepsis. Furthermore, patients with sepsis exhibited disturbances in gut amino acid metabolism compared with healthy controls; namely, tryptophan metabolism was tightly related to an altered microbiota and the severity of sepsis.

CONCLUSION

Alterations in microbial and metabolic features in the gut corresponded with the progression of sepsis. Our findings may help to predict the clinical outcome of patients in the early stage of sepsis and provide a translational basis for exploring new therapies.

Okadaic Acid Activates JAK/STAT Signaling to Affect Xenobiotic Metabolism in HepaRG Cells

Okadaic acid (OA) is a marine biotoxin that is produced by algae and accumulates in filter-feeding shellfish, through which it enters the human food chain, leading to diarrheic shellfish poisoning (DSP) after ingestion. Furthermore, additional effects of OA have been observed, such as cytotoxicity. Additionally, a strong downregulation of the expression of xenobiotic-metabolizing enzymes in the liver can be observed. The underlying mechanisms of this, however, remain to be examined. In this study, we investigated a possible underlying mechanism of the downregulation of cytochrome P450 (CYP) enzymes and the nuclear receptors pregnane X receptor (PXR) and retinoid-X-receptor alpha (RXRα) by OA through NF-κB and subsequent JAK/STAT activation in human HepaRG hepatocarcinoma cells. Our data suggest an activation of NF-κB signaling and subsequent expression and release of interleukins, which then activate JAK-dependent signaling and thus STAT3. Moreover, using the NF-κB inhibitors JSH-23 and Methysticin and the JAK inhibitors Decernotinib and Tofacitinib, we were also able to demonstrate a connection between OA-induced NF-κB and JAK signaling and the downregulation of CYP enzymes. Overall, we provide clear evidence that the effect of OA on the expression of CYP enzymes in HepaRG cells is regulated through NF-κB and subsequent JAK signaling.

Prenatal Lipopolysaccharide Exposure Alters Hepatic Drug-Metabolizing Enzyme Expression in Mouse Offspring via Histone Modifications

Inflammation is a major regulator of drug-metabolizing enzymes (DMEs), therefore contributing to the interindividual variability of drug effects. However, whether prenatal inflammation affects DMEs expression in offspring remains obscure. This study investigated the effects of prenatal lipopolysaccharide (LPS) exposure on hepatic expression of inflammatory-related genes, nuclear receptors, and DMEs in offspring mice. Prenatal LPS exposure on gestational day (GD) 10 led to higher expression of NF-κB, Pxr, and Cyp2b10, while lower expression of Car, Ahr, Cyp3a11, and Ugt1a1 in postnatal day (PD) 30 offspring. However, multiple doses of LPS exposure on GD10-14 resulted in higher levels of inflammatory-related genes, Cyp1a2, and Cyp2b10, and lower levels of Pxr and Cyp3a11 in PD30 offspring liver. For PD60 offspring, decreased hepatic expression of NF-κB and IL-6, and increased expression of Pxr and Cyp3a11 were seen in single-dose LPS groups, whereas opposite results were observed in the multiple-dose LPS groups. Notably, enhanced H3K4me3 levels in the PXR response elements of the Cyp3a11 promoter were observed in the liver of PD60 offspring mice from dams treated with multiple doses of LPS during pregnancy. Overall, this study suggests that parental LPS exposure could persistently alter the hepatic expression of DMEs, and histone modifications may contribute to the long-term effects.

Effects of NR1I2 and ABCB1 Genetic Polymorphisms on Everolimus Pharmacokinetics in Japanese Renal Transplant Patients

The purpose of this study was to evaluate the effects of NR1I2 (7635G>A and 8055C>T) and ABCB1 (1236C>T, 2677G>T/A, and 3435C>T) genetic polymorphisms on everolimus pharmacokinetics in 98 Japanese renal transplant patients. On day 15 after everolimus administration, blood samples were collected just prior to and 1, 2, 3, 4, 6, 9, and 12 h after administration. The dose-adjusted area under the blood concentration−time curve (AUC0-12) of everolimus was significantly lower in patients with the NR1I2 8055C/C genotype than in those with other genotypes (p = 0.022) and was significantly higher in male patients than female patients (p = 0.045). Significant correlations between the dose-adjusted AUC0-12 of everolimus and age (p = 0.001), aspartate transaminase (p = 0.001), and alanine transaminase (p = 0.005) were found. In multivariate analysis, aging (p = 0.008) and higher alanine transaminase levels (p = 0.032) were independently predictive of a higher dose-adjusted everolimus AUC0-12. Aging and hepatic dysfunction in patients may need to be considered when evaluating dose reductions in everolimus. In renal transplant patients, management using everolimus blood concentrations after administration may be more important than analysis of NR1I2 8055C>T polymorphism before administration.

Sepsis-Induced Brain Dysfunction: Pathogenesis, Diagnosis, and Treatment

Dysregulated host response to infection, which cause life-threatening organ dysfunction, was defined as sepsis. Sepsis can cause acute and long-term brain dysfunction, namely, sepsis-associated encephalopathy (SAE) and cognitive impairment. SAE refers to changes in consciousness without direct evidence of central nervous system infection. It is highly prevalent and may cause poor outcomes in sepsis patients. Cognitive impairment seriously affects the life quality of sepsis patients and increases the medical burden. The pathogenesis of sepsis-induced brain dysfunction is mainly characterized by the interaction of systemic inflammation, blood-brain barrier (BBB) dysfunction, neuroinflammation, microcirculation dysfunction, and brain dysfunction. Currently, the diagnosis of sepsis-induced brain dysfunction is based on clinical manifestation of altered consciousness along with neuropathological examination, and the treatment is mainly involves controlling sepsis. Although treatments for sepsis-induced brain dysfunction have been tested in animals, clinical treat sepsis-induced brain dysfunction is still difficult. Therefore, we review the underlying mechanisms of sepsis-induced brain injury, which mainly focus on the influence of systemic inflammation on BBB, neuroinflammation, brain microcirculation, and the brain function, which want to bring new mechanism-based directions for future basic and clinical research aimed at preventing or ameliorating brain dysfunction.

Identifying Drug-Induced Liver Injury Associated With Inflammation-Drug and Drug-Drug Interactions in Pharmacologic Treatments for COVID-19 by Bioinformatics and System Biology Analyses: The Role of Pregnane X Receptor

Of the patients infected with coronavirus disease 2019 (COVID-19), approximately 14–53% developed liver injury resulting in poor outcomes. Drug-induced liver injury (DILI) is the primary cause of liver injury in COVID-19 patients. In this study, we elucidated liver injury mechanism induced by drugs of pharmacologic treatments against SARS-CoV-2 (DPTS) using bioinformatics and systems biology. Totally, 1209 genes directly related to 216 DPTS (DPTSGs) were genes encoding pharmacokinetics and therapeutic targets of DPTS and enriched in the pathways related to drug metabolism of CYP450s, pregnane X receptor (PXR), and COVID-19 adverse outcome. A network, constructed by 110 candidate targets which were the shared part of DPTSGs and 445 DILI targets, identified 49 key targets and four Molecular Complex Detection clusters. Enrichment results revealed that the 4 clusters were related to inflammatory responses, CYP450s regulated by PXR, NRF2-regualted oxidative stress, and HLA-related adaptive immunity respectively. In cluster 1, IL6, IL1B, TNF, and CCL2 of the top ten key targets were enriched in COVID-19 adverse outcomes pathway, indicating the exacerbation of COVID-19 inflammation on DILI. PXR-CYP3A4 expression of cluster 2 caused DILI through inflammation-drug interaction and drug-drug interactions among pharmaco-immunomodulatory agents, including tocilizumab, glucocorticoids (dexamethasone, methylprednisolone, and hydrocortisone), and ritonavir. NRF2 of cluster 3 and HLA targets of cluster four promoted DILI, being related to ritonavir/glucocorticoids and clavulanate/vancomycin. This study showed the pivotal role of PXR associated with inflammation-drug and drug-drug interactions on DILI and highlighted the cautious clinical decision-making for pharmacotherapy to avoid DILI in the treatment of COVID-19 patients.

The impact of sepsis on hepatic drug metabolism in critically ill patients: a narrative review

INTRODUCTION

Hepatic drug metabolism is important in improving drug dosing strategies in sepsis. Pharmacokinetics in the critically ill population are severely altered due to changes in absorption, distribution, excretion and metabolization. Hepatic drug metabolism might be altered due to changes in hepatic blood flow, drug metabolizing protein availability, and protein binding. The purpose of this review is to examine evidence on whether hepatic drug metabolism is significantly affected in septic patients, and to provide insights in the need for future research.

AREAS COVERED

This review describes the effect of sepsis on hepatic drug metabolism in humans. Clinical trials, pathophysiological background information and example drug groups are further discussed. The literature search has been conducted in Embase, Medline ALL Ovid, and Cochrane CENTRAL register of trials.

EXPERT OPINION

Limited research has been conducted on drug metabolism in the sepsis population, with some trials having researched healthy individuals using endotoxin injections. Notwithstanding this limitation, hepatic drug metabolism seems to be decreased for certain drugs in sepsis. More research on the pharmacokinetic behavior of hepatic metabolized drugs in sepsis is warranted, using inflammatory biomarkers, hemodynamic changes, mechanical ventilation, organ support, and catecholamine infusion as possible confounders.

Potential Pharmacokinetic Effect of Chicken Xenobiotic Receptor Activator on Sulfadiazine: Involvement of P-glycoprotein Induction

Studies on pharmacokinetic drug−drug interactions have highlighted the importance of P-glycoprotein (P-gp) because of its involvement in substrate drug transport. This study aimed to investigate the role of chicken xenobiotic receptor (CXR) in the regulation of P-gp and its influences on pharmacokinetics of P-gp substrate sulfadiazine. ALAS1 and CYP2C45, the prototypical target genes of CXR, were used as a positive indicator for CXR activation in this study. Results show that ABCB1 gene expression was upregulated, and transporter activity was increased when exposed to the CXR activator metyrapone. Using ectopic expression techniques and RNA interference to manipulate the cellular CXR status, we confirmed that ABCB1 gene regulation depends on CXR. In vivo experiments showed that metyrapone induced ABCB1 in the liver, kidney, duodenum, jejunum and ileum of chickens. In addition, metyrapone significantly changed the pharmacokinetic behavior of orally administered sulfadiazine, with a Cmax (8.01 vs. 9.61 μg/mL, p < 0.05) and AUC0-t (31.46 vs. 45.59 h·mg/L, p < 0.01), as well as a higher T1/2λ (2.42 vs.1.67 h, p < 0.05), Cl/F (0.62 vs. 0.43 L/h/kg, p < 0.01) and Vz/F (2.16 vs.1.03 L/kg, p < 0.01). Together, our data suggest that CXR is involved in the regulation of P-gp, and, consequently, the CXR activator can affect, at least in part, the pharmacokinetic behavior of orally administered sulfadiazine.

Metagenomic Analysis of Plasma Microbial Extracellular Vesicles in Patients Receiving Mechanical Ventilation: A Pilot Study

Background: Previous studies reported a significant association between pneumonia outcome and the respiratory microbiome. There is increasing interest in the roles of bacterial extracellular vesicles (EVs) in various diseases. We studied the composition and function of microbiota-derived EVs in the plasma of patients receiving mechanical ventilation to evaluate whether they can be used as a diagnostic marker and to predict clinical outcomes. Methods: Plasma samples (n = 111) from 59 mechanically ventilated patients (41 in the pneumonia group; 24 in the nursing home and hospital-associated infection [NHAI] group) were prospectively collected on days one and seven. After isolating the bacterial EVs from plasma samples, nucleic acid was extracted for 16S rRNA gene pyrosequencing. The samples were evaluated to determine the α and β diversity, bacterial composition, and predicted functions. Results: Principal coordinates analysis revealed significantly different clustering of microbial EVs between the pneumonia and non-pneumonia groups. The proportions of Lactobacillus, Cutibacterium, and Sphingomonas were significantly different between the pneumonia and non-pneumonia groups. In addition, the abundances of Lactobacillus and Bifidobacterium were significantly higher in the non-NHAI than the NHAI group. In the analysis of β diversity, the structure of microbial EVs differed significantly different between 28-day survivors and non-survivors (Bray-Curtis distance, p = 0.014). Functional profiling revealed significant differences between the pneumonia and non-pneumonia groups. The longitudinal change in predicted functions of microbial EV genes showed a significant difference between 28-day survivors and non-survivors. Conclusions: Bacterial microbiota–derived EVs in the plasma have potential as diagnostic and prognostic markers for patients receiving mechanical ventilation. Further large prospective studies are needed to determine the clinical utility of plasma microbiota-EVs in intubated patients.

Pharmacokinetic Imaging Using 99mTc-Mebrofenin to Untangle the Pattern of Hepatocyte Transporter Disruptions Induced by Endotoxemia in Rats

Endotoxemia-induced inflammation may impact the activity of hepatocyte transporters, which control the hepatobiliary elimination of drugs and bile acids. ^99mTc-mebrofenin is a non-metabolized substrate of transporters expressed at the different poles of hepatocytes. ^99mTc-mebrofenin imaging was performed in rats after the injection of lipopolysaccharide (LPS). Changes in transporter expression were assessed using quantitative polymerase chain reaction of resected liver samples. Moreover, the particular impact of pharmacokinetic drug–drug interactions in the context of endotoxemia was investigated using rifampicin (40 mg/kg), a potent inhibitor of hepatocyte transporters. LPS increased ^99mTc-mebrofenin exposure in the liver (1.7 ± 0.4-fold). Kinetic modeling revealed that endotoxemia did not impact the blood-to-liver uptake of ^99mTc-mebrofenin, which is mediated by organic anion-transporting polypeptide (Oatp) transporters. However, liver-to-bile and liver-to-blood efflux rates were dramatically decreased, leading to liver accumulation. The transcriptomic profile of hepatocyte transporters consistently showed a downregulation of multidrug resistance-associated proteins 2 and 3 (Mrp2 and Mrp3), which mediate the canalicular and sinusoidal efflux of ^99mTc-mebrofenin in hepatocytes, respectively. Rifampicin effectively blocked both the Oatp-mediated influx and the Mrp2/3-related efflux of ^99mTc-mebrofenin. The additive impact of endotoxemia and rifampicin led to a 3.0 ± 1.3-fold increase in blood exposure compared with healthy non-treated animals. ^99mTc-mebrofenin imaging is useful to investigate disease-associated change in hepatocyte transporter function.

Melatonin ameliorates trimethyltin chloride-induced cardiotoxicity: The role of nuclear xenobiotic metabolism and Keap1-Nrf2/ARE axis-mediated pyroptosis

Trimethyltin chloride (TMT) is a stabilizer for polyvinyl chloride plastics that causes serious health hazards in nontarget organisms. Melatonin (MT) exhibits powerful protective effects in cardiac diseases. As a new environmental pollutant, TMT-induced cardiotoxicity and the protective effects of MT remain unclear. To explore this, the mice were treated with TMT (2.8 mg/kg) and/or MT (10 mg/kg) for 7 days. Firstly, the histopathological and ultrastructural evaluation showed that TMT induced cardiac damage, tumescent rupture and nuclear pyknosis. Moreover, TMT elevated the expressions of pyroptosis genes NLRP3, ASC and Cas1 and inflammation factors IL-6, IL-17 and TNFα. Secondly, TMT reduced antioxidant enzymes (GSH, CAT and T-AOC) via decreasing the expression of genes associated with the Keap1-Nrf2/ARE pathway to increase oxidative stress. Thirdly, TMT decreased the expression of genes associated with the ARE-driven drug metabolizing enzymes (DMEs), including Akr7a3, Akr1b8, and Akr1b10. Besides, TMT upregulated the mRNA expression of nuclear Xenobiotic metabolism on cytochrome P450s enzymes via increasing the expression of CAR, PXP, and AHR genes. Furthermore, MT treatment mitigated the aforementioned adverse changes induced by TMT. Overall, these results demonstrated that TMT caused pyroptosis and inflammation to aggravate cardiac damage via inducing excessive oxidative stress, imbalance of DMEs homeostasis, and nuclear Xenobiotic metabolism disorder, which could be alleviated by MT.

Research Progress on the Pharmacological Action of Schisantherin A

Schisantherin A (Sch A) is a dibenzocyclooctadiene lignan monomer isolated from the fruit of Schisandra chinensis (Turcz.) Baill. (S. chinensis). At present, many studies have shown that Sch A has a wide range of pharmacological effects, including its anti-Parkinson and anti-inflammatory effects and ability to protect the liver, protect against ischemia-reperfusion (I/R) injury, suppress osteoclast formation, and improve learning and memory. Its mechanism may be related to the antioxidant, anti-inflammatory, and antiapoptotic properties of Sch A through the MAPK, NF-κB, AKT/GSK3β, and PI3K/AKT pathways. This is the first review of the recent studies on the pharmacological mechanism of Sch A.

Pharmacogene Variants Associated with Liver Transplant in a Twelve-Year Clinical Follow-Up

Some gene polymorphisms have been previously associated individually with tacrolimus efficacy and toxicity, but no long-term study to determine the role of pharmacogene variants in the clinical evolution of liver-transplanted patients has been addressed so far. In the present work, we analyzed the relation between highly-evidenced genetic polymorphisms located in relevant pharmacogenes and the risk of suffering premature death and other comorbidities such as cancer, diabetes mellitus, arterial hypertension, graft rejection, infections and nephrotoxicities in a cohort of 87 patients (8 were excluded due to early loss of follow-up) transplanted at Hospital La Fe in Valencia (Spain) during a 12-year follow-up. Employing a logistic regression model with false discovery rate penalization and Kaplan–Meier analyses, we observed significant association between survival rates and metabolizer genes. In this sense, our results show an association between MTHFR gene variants in donor rs1801133 (HR: 7.90; p-value: 0.032) and recipient rs1801131 (HR: 7.34; p-value: 0.036) and the group of patients who died during the follow-up period, supporting the interest of confirming these results with larger patient cohorts. In addition, donor polymorphisms in UGT1A9 metabolizer gene rs6714486 (OR: 0.13; p-value: 0.032) were associated with a lower risk of suffering from de novo cancer. Genetic variants in CYP2B6 metabolizer gene rs2279343 demonstrated an association with a risk of infection. Other variants in different locations of SLCO1A2, ABCC2 and ABCB1 transporter genes were associated with a lower risk of suffering from type 2 diabetes mellitus, chronic and acute nephrotoxicities and arterial hypertension. Results suggest that pharmacogenetics-derived information may be an important support for personalized drug prescription, clinical follow-up and the evolution of liver-transplanted patients.

Exposure to High-Altitude Environment is Associated with Drug Transporters Change: miR-873-5p-Mediated Alteration of Function and Expression Levels of Drug Transporters under Hypoxia

Hypoxia is the main characteristic of a high-altitude environment, affect ing drug metabolism. However, so far, the mechanism of miRNA involved in the regulation of drug metabolism and transporters under high-altitude hypoxia is still unclear. This study aims to investigate the function s and expression levels of multidrug resistance protein 1 ( MDR1 ), m ultidrug resistance-associated protein 2 ( MRP2 ), breast cancer resistance protein ( BCRP ) , peptide transport 1 (PEPT1), and organic anion-transporting polypeptides 2B1 (OATP2B1) in rats and Caco-2 cells after exposure to high - altitude hypoxia. The protein and mRNA expression of MDR1 , MRP2, BCRP, PEPT1, and OATP2B1 were determined by Western blot and qPCR. The function s of MDR1 , MRP2, BCRP, PEPT1, and OATP2B1 were evaluated by determining the effective intestinal permeability and a bsorption rate constants of their specific substrates in rats under high-altitude hypoxia , and uptake and transport studies were performed on Caco-2 cells . To screen the miRNA associated with hypoxia, Caco-2 cells were examined by high throughput sequencing . We observed that the miR-873-5p was significantly decreased under hypoxia and might target MDR1 and pregnane X receptor ( PXR). To clarify whether miR-873-5p regulates MDR1 and pregnane X receptor (PXR) under hypoxia, Caco-2 cells were transfected with mimics or inhibitors of miR-873-5p and negative control (NC). The function and expression of drug transporters were found to be significantly increased in rats and Caco-2 cells under hypoxia. We found that miR-873-5p regulated MDR1 and PXR expression. Herein, it is shown that miRNA may affect the expression of drug transporter and nuclear receptor under hypoxia. Significance Statement This study explores if alterations to the microRNAs, induced by high-altitude hypoxia, can be translated to altered drug transporters. Among miRNAs, which show a significant change in a hypoxic environment, miR-873-5p can act on the MDR1 gene; however, there are multiple miRNAs that can act on the PXR. We speculate that the miRNA-PXR-Drug transporter axis is important in the physiological disposition of drugs. The results of this study are anticipated to be helpful for rational pharmaceutical use in high - altitude environments .

Combination of tumor mutation burden and immune infiltrates for the prognosis of lung adenocarcinoma

BACKGROUND

Tumor mutation burden (TMB) levels are associated with immune infiltrates in the tumor microenvironment and can modulate the responses to immune checkpoint inhibitors (ICIs) in lung adenocarcinoma (LUAD) patients. This study aimed at exploring the potential role of a signature of genes associated with TMB and immune infiltrates and the relevant nomogram in the prognosis of LUAD.

MATERIALS AND METHODS

The TMB levels in LUAD patients in the Cancer Genome Atlas (TCGA) were analyzed. The differentially expressed genes (DEGs) between the higher- and lower-TMB subgroups were functionally analyzed. The immune-related DEGs and their relationship with immune infiltrates in the tumor environment between two subgroups were analyzed. Nine immune-related DEGs were used to generate a TMB-related immune signature. The sensitivity to immunotherapy in TCGA-LUAD patients was analyzed by immunophenotypic scores (IPS). Subsequently, a nomogram was generated using tumor-related parameters and the signature score. The signature or nomogram values in predicting overall survival (OS) were evaluated and validated in LUAD patients in the GSE30219 and GSE72094.

RESULT

There were 468 DEGs between the higher and lower-TMB subgroups of LUAD patients. The TMB levels were associated positively with the number of immune infiltrates in LUAD patients. Nine DEGs were related to immune infiltrates in the tumor environment. The higher signature scores (high-risk) were associated with poor prognosis of LUAD in the TCGA, which was validated in LUAD patients of the GSE30219 and GSE72094 datasets. Interestingly, the patients in the high-risk group had higher PD-L1 expression in their tumors and the risk scores in LUAD patients. The IPS of LUAD patients in the high-risk group were predicted to benefit from immunotherapy. Finally, the nomogram had high AUC values in predicting the OS of LUAD patients.

CONCLUSION

The TMB-related immune signature or nomogram is valuable for the prognosis of LUAD patients and evaluating their responses to ICIs. These relevant genes may participate into the pathogenesis, ICIs, and drug resistance of LUAD.

Xanthohumol ameliorates Diet-Induced Liver Dysfunction via Farnesoid X Receptor-Dependent and Independent Signaling

The farnesoid X receptor (FXR) plays a critical role in the regulation of lipid and bile acid (BA) homeostasis. Hepatic FXR loss results in lipid and BA accumulation, and progression from hepatic steatosis to nonalcoholic steatohepatitis (NASH). This study aimed to evaluate the effects of xanthohumol (XN), a hop-derived compound mitigating metabolic syndrome, on liver damage induced by diet and FXR deficiency in mice. Wild-type (WT) and liver-specific FXR-null mice (FXR^Liver−/−) were fed a high-fat diet (HFD) containing XN or the vehicle formation followed by histological characterization, lipid, BA and gene profiling. HFD supplemented with XN resulted in amelioration of hepatic steatosis and decreased BA concentrations in FXR^Liver−/− mice, the effect being stronger in male mice. XN induced the constitutive androstane receptor (CAR), pregnane X receptor (PXR) and glucocorticoid receptor (GR) gene expression in the liver of FXR^Liver−/− mice. These findings suggest that activation of BA detoxification pathways represents the predominant mechanism for controlling hydrophobic BA concentrations in FXR^Liver−/− mice. Collectively, these data indicated sex-dependent relationship between FXR, lipids and BAs, and suggest that XN ameliorates HFD-induced liver dysfunction via FXR-dependent and independent signaling.

Immunization and Drug Metabolizing Enzymes: Focus on Hepatic Cytochrome P450 3A

OBJECTIVE

Infectious disease emergencies like the 2013-2016 Ebola epidemic and the 2009 influenza and current SARS-CoV-2 pandemics illustrate that vaccines are now given to diverse populations with preexisting pathologies requiring pharmacological management. Many natural biomolecules (steroid hormones, fatty acids, vitamins) and ~60% of prescribed medications are processed by hepatic cytochrome P450 (CYP) 3A4. The objective of this work was to determine the impact of infection and vaccines on drug metabolism.

METHODS

The impact of an adenovirus-based vaccine expressing Ebola glycoprotein (AdEBO) and H1N1 and H3N2 influenza viruses on hepatic CYP 3A4 and associated nuclear receptors was evaluated in human hepatocytes (HC-04 cells) and in mice.

RESULTS

CYP3A activity was suppressed by 55% in mice 24 h after administration of mouse-adapted H1N1, while ˂10% activity remained in HC-04 cells after infection with H1N1 and H3N2 due to global suppression of cellular translation capacity, indicated by reduction (70%, H1N1, 56%, H3N2) of phosphorylated eukaryotic translation initiation factor 4e (eIF4E). AdEBO suppressed CYP3A activity in vivo (44%) and in vitro (26%) 24 hours after infection.

CONCLUSION

As the clinical evaluation of vaccines for SARS-CoV-2 and other global pathogens rise, studies to evaluate the impact of new vaccines and emerging pathogens on CYP3A4 and other metabolic enzymes are warranted to avoid therapeutic failures that could further compromise the public health during infectious disease emergencies.

Constitutive androstane receptor induced-hepatomegaly and liver regeneration is partially via yes-associated protein activation

The constitutive androstane receptor (CAR, NR3I1) belongs to nuclear receptor superfamily. It was reported that CAR agonist TCPOBOP induces hepatomegaly but the underlying mechanism remains largely unknown. Yes-associated protein (YAP) is a potent regulator of organ size. The aim of this study is to explore the role of YAP in CAR activation-induced hepatomegaly and liver regeneration. TCPOBOP-induced CAR activation on hepatomegaly and liver regeneration was evaluated in wild-type (WT) mice, liver-specific YAP-deficient mice, and partial hepatectomy (PHx) mice. The results demonstrate that TCPOBOP can increase the liver-to-body weight ratio in wild-type mice and PHx mice. Hepatocytes enlargement around central vein (CV) area was observed, meanwhile hepatocytes proliferation was promoted as evidenced by the increased number of KI67⁺ cells around portal vein (PV) area. The protein levels of YAP and its downstream targets were upregulated in TCPOBOP-treated mice and YAP translocation can be induced by CAR activation. Co-immunoprecipitation results suggested a potential protein–protein interaction of CAR and YAP. However, CAR activation-induced hepatomegaly can still be observed in liver-specific YAP-deficient (Yap^–/–) mice. In summary, CAR activation promotes hepatomegaly and liver regeneration partially by inducing YAP translocation and interaction with YAP signaling pathway, which provides new insights to further understand the physiological functions of CAR.

Protective Role of St. John's Wort and Its Components Hyperforin and Hypericin against Diabetes through Inhibition of Inflammatory Signaling: Evidence from In Vitro and In Vivo Studies

Diabetes mellitus is a very common chronic disease with progressively increasing prevalence. Besides the well-known autoimmune and inflammatory pathogenesis of type 1 diabetes, in many people, metabolic changes and inappropriate lifestyle favor a subtle chronic inflammatory state that contributes to development of insulin resistance and progressive loss of β-cell function and mass, eventually resulting in metabolic syndrome or overt type 2 diabetes. In this paper, we review the anti-inflammatory effects of the extract of Hypericum perforatum L. (St. John's wort, SJW) and its main active ingredients firstly in representative pathological situations on inflammatory basis and then in pancreatic β cells and in obese or diabetic animal models. The simultaneous and long-lasting inhibition of signal transducer and activator of transcription (STAT)-1, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and mitogen-activated protein kinases (MAPKs)/c-jun N-terminal kinase (JNK) signaling pathways involved in pro-inflammatory cytokine-induced β-cell dysfunction/death and insulin resistance make SJW particularly suitable for both preventive and therapeutic use in metabolic diseases. Hindrance of inflammatory cytokine signaling is likely dependent on the hyperforin content of SJW extract, but recent data reveal that hypericin can also exert relevant protective effects, mediated by activation of the cyclic adenosine monophosphate (cAMP)/protein kinase cAMP-dependent (PKA)/adenosine monophosphate activated protein kinase (AMPK) pathway, against high-fat-diet-induced metabolic abnormalities. Actually, the mechanisms of action of the two main components of SJW appear complementary, strengthening the efficacy of the plant extract. Careful quantitative analysis of SJW components and suitable dosage, with monitoring of possible drug-drug interaction in a context of remarkable tolerability, are easily achievable pre-requisites for forthcoming clinical applications.

FBI-1 enhanced the resistance of triple-negative breast cancer cells to chemotherapeutic agents via the miR-30c/PXR axis

The factor that binds to the inducer of short transcripts-1 (FBI-1) is a transcription suppressor and an important proto-oncogene that plays multiple roles in carcinogenesis and therapeutic resistance. In the present work, our results indicated that FBI-1 enhanced the resistance of triple-negative breast cancer (TNBC) cells to chemotherapeutic agents by repressing the expression of micoRNA-30c targeting the pregnane X receptor (PXR). The expression of FBI-1 was positively related to PXR and its downstream drug resistance-related genes in TNBC tissues. FBI-1 enhanced the expression of PXR and enhanced the activation of the PXR pathway. The miR-30c decreased the expression of PXR by targeting the 3'-UTR of PXR, and FBI-1 increased the expression of PXR by repressing miR-30c's expression. Through the miR-30c/PXR axis, FBI-1 accelerated the clearance or elimination of antitumor agents in TNBC cells (the TNBC cell lines or the patients derived cells [PDCs]) and induced the resistance of cells to antitumor agents. Therefore, the results indicated that the miR-30c/PXR axis participates in the FBI-1-mediated drug-resistance of TNBC cells.