The effects of high-intensity interval training and Iranian propolis extract on serum levels of TRPV4 and CYP2E1 proteins in patients with nonalcoholic fatty liver.

INTRODUCTION: Non-alcoholic fatty liver disease (NAFLD) is the most common cause of liver failure, fibrosis, cirrhosis, and liver cancer, which can eventually lead to death. AIM: To investigate the effects of high-intensity interval training (HIIT) and iranian propolis extract on serum levels of transient receptor potential cation channel subfamily V member 4 (TRPV4) and cytochrome P450 2E1 (CYP2E1) proteins in patients with NAFLD. METHODS: Thirty-two patients with NAFLD (mean±standard deviation of age: 45.1±3.6 years; body mass index: 30.0±3.6 kg/m2) were assigned in a randomized control trial to one of the following groups: HIIT (n=8), propolis supplement (n=8), propolis + HIIT (n=8), and controls (n=8). The subjects participated in eight weeks of HIIT (one bout of 1-min intervals at 80-95% of the maximal heart-rate, interspersed by two min at 50-55% of the reserve heart-rate). The Propolis supplement was taken three times a day by the patients in the form of 50 mg tablet after the main meals. Body composition, liver injury test (eg; Alanine- and Aspartate- aminotransferase levels), liver ultrasound and serum levels of TRPV4 and CYP2E1 were measured before and after intervention. One-way analysis of variance was used to compare post-tests among the groups. RESULTS: HIIT significantly reduced serum levels of TRPV4 protein (p=0.001). The reduction in CYP2E1 was not significant in HIIT group (p=0.075). Propolis consumption had no significant effect on serum levels of CYP2E1 protein (p=0.059), and TRPV4 (p=0.072). There was a significant decrease in TRPV4 and CYP2E1 in the HIIT (p=0.001) and propolis supplement (p=0.032) groups. CONCLUSION: HIIT and propolis supplementation can be used to reduce TRPV4 and CYP2E1, which in turn reduces oxidative stress and inflammation in patients with NAFLD.

Oral magnesium prevents acetaminophen-induced acute liver injury by modulating microbial metabolism.

Acetaminophen overuse is a common cause of acute liver failure (ALF). During ALF, toxins are metabolized by enzymes such as CYP2E1 and transformed into reactive species, leading to oxidative damage and liver failure. Here, we found that oral magnesium (Mg) alleviated acetaminophen-induced ALF through metabolic changes in gut microbiota that inhibit CYP2E1. The gut microbiota from Mg-supplemented humans prevented acetaminophen-induced ALF in mice. Mg exposure modulated Bifidobacterium metabolism and enriched indole-3-carboxylic acid (I3C) levels. Formate C-acetyltransferase (pflB) was identified as a key Bifidobacterium enzyme involved in I3C generation. Accordingly, a Bifidobacterium pflB knockout showed diminished I3C generation and reduced the beneficial effects of Mg. Conversely, treatment with I3C or an engineered bacteria overexpressing Bifidobacterium pflB protected against ALF. Mechanistically, I3C bound and inactivated CYP2E1, thus suppressing formation of harmful reactive intermediates and diminishing hepatocyte oxidative damage. These findings highlight how interactions between Mg and gut microbiota may help combat ALF.

Efficacy of oltipraz in preventing acetaminophen-induced liver injury in mice.

Oltipraz (OPZ) is a synthetic dithiolethione with potential as a cancer chemopreventive agent, which can work by inducing detoxification enzymes. OPZ is an activator of nuclear factor erythroid 2-related factor 2 (Nrf2), suggesting its involvement in enzyme induction and possible protection against drug-induced liver injury. In this study, we present OPZ-mediated protection of mice against acetaminophen (APAP)-induced liver injury and discuss its possible contributing factors. Overnight-fasted male CD-1 mice were administered APAP intraperitoneally, and some mice were administered OPZ 16 h before APAP. Hepatotoxicity was assessed by measuring serum alanine aminotransferase leakage and histopathological evaluation. The hepatic mRNA expressions of CYP2E1, glutamate cysteine ligase (GCL), and NAD(P)H:quinone oxidoreductase (NQO1) were measured by real-time reverse-transcription polymerase chain reaction. OPZ protected mice from APAP-induced liver injury in a dose-dependent manner, but did not alter hepatic glutathione (GSH) content or GCL expression in control mice, indicating that its hepatoprotective effect is not due to changes in basal GSH levels. OPZ did not affect CYP2E1 expression or APAP-induced early GSH depletion, suggesting it does not inhibit the metabolic activation of APAP to produce N-acetyl-p-benzoquinone imine. In contrast, after GSH depletion, OPZ accelerated hepatic GSH recovery. APAP significantly increased GCL expression during liver injury, but OPZ treatment only led to additional NQO1 expression. This suggests that NQO1 is responsible for the enhanced GSH recovery and protection against APAP-induced liver injury seen in OPZ-treated mice. In summary, OPZ protects against APAP-induced liver injury by inducing NQO1 expression and resulting in improved GSH recovery.

Graphene oxide-induced, reactive oxygen species-mediated mitochondrial dysfunctions and apoptosis: high-dose toxicity in normal cells.

Aim: The cytotoxic effects of graphene oxide nanoparticles (GONPs) using MTT assays, observance of apoptotic markers, and oxidative stress were outlined. Materials & methods: Rat embryonic fibroblasts (REFs) and human epithelial breast cells (HBLs) were used at 250, 500 and 750 µg/ml concentrations. Results: Significant cytotoxic and apoptotic effects were observed. Analyses of CYP2E1 and malondialdehyde concentrations in REF and HBL-100 cell lines after exposing to GONPs confirmed the nanomaterials toxicity. However, the glutathione levels in REF and HBL-100 cell lines showed a substantial reduction compared with the control. The cytochrome CYP2E1, glutathione, malondialdehyde and caspase-3 alterations provided a plausible interlinked relationship. Conclusion: The study confirmed the GONPs cytotoxic effects on REF and HBL-100 cell lines. The outcome suggested caution in wide-spread applications of GONPs, which could have implications for occupational health also.

Cyp2e1 knockdown attenuates high glucose-induced apoptosis and oxidative stress of cardiomyocytes by activating PI3K/Akt signaling.

AIMS: Cyp2e1 is a crucial CYP450 enzyme participating in diabetes and cardiovascular disorder. However, the role of Cyp2e1 in diabetic cardiomyopathy (DCM) has never been reported. Thus, we intended to identify the effects of Cyp2e1 on cardiomyocytes under high glucose (HG) conditions. METHODS: Identification of differentially expressed genes in DCM and control rats was performed using bioinformatics analysis based on GEO database. The Cyp2e1-knockdown H9c2 and HL-1 cells were established through transfection with si-Cyp2e1. Western blot analysis was performed to determine the expression levels of Cyp2e1, apoptosis-related proteins and PI3K/Akt signaling-associated proteins. TUNEL assay was performed to assess apoptotic rate. Reactive oxygen species (ROS) generation was examined by DCFH2-DA staining assay. RESULTS: From the bioinformatics analysis, Cyp2e1 was confirmed as an upregulated gene in DCM tissues. In vitro assays proved that Cyp2e1 expression was markedly increased in HG-induced H9c2 and HL-1 cells. Cyp2e1 knockdown attenuated HG-induced apoptosis in both H9c2 and HL-1 cells, as proved by deceased apoptotic rate, relative cleaved caspase-3/caspase-3 level, and caspase-3 activity. Cyp2e1 knockdown reduced ROS generation and elevated the expression level of nuclear Nrf2 in HG-induced H9c2 and HL-1 cells. Increased relative levels of p-PI3K/PI3K and p-Akt/Akt were found in Cyp2e1-knockdown H9c2 and HL-1 cells. Inhibition of PI3K/Akt using LY294002 reversed the inhibitory effects of Cyp2e1 knockdown on cell apoptosis and ROS generation on cardiomyocytes. CONCLUSIONS: Cyp2e1 knockdown attenuated HG-induced apoptosis and oxidative stress by activating PI3K/Akt signaling in cardiomyocytes. These findings suggested that Cyp2e1 might be potentially used as an effective therapeutic strategy for DCM.

A Biomimetic Nanoparticle Exerting Protection against Acute Liver Failure by Suppressing CYP2E1 Activity and Scavenging Excessive ROS.

Acute liver failure (ALF) is a severe liver disease caused by many reasons. One of them is the overdosed acetaminophen (APAP), which is metabolized into N-acetyl-p-benzoquinone imine (NAPQI), an excessive toxic metabolite, by CYP2E1, resulting in excessive reactive oxygen species (ROS), exhausted glutathione (GSH), and thereafter hepatocyte necrosis. N-acetylcysteine is the Food and Drug Administration-approved drug for detoxification of APAP, but it has limited clinical application due to the short therapeutic time window and concentration-related adverse effects. In this study, a carrier-free and bilirubin dotted nanoparticle (B/BG@N) is developed, which is formed using bilirubin and 18ß-Glycyrrhetinic acid, and bovine serum albumin (BSA) is then adsorbed to mimic the in vivo behavior of the conjugated bilirubin for hitchhiking. The results demonstrate that B/BG@N can effectively reduce the production of NAPQI as well as exhibit antioxidant effects against intracellular oxidative stress via regulating the nuclear factor erythroid 2-related factor 2/heme oxygenase-1 signal axis and reducing the production of inflammatory factors. In vivo study shows that B/BG@N can effectively improve the clinical symptom of the mice model. This study suggests that B/BG@N own increases circulation half-life, improves accumulation in the liver, and dual detoxification, providing a promising strategy for clinical ALF treatment.

Fisetin Attenuates Paracetamol-Induced Hepatotoxicity by Regulating CYP2E1 Enzyme.

Paracetamol is one of the drugs that cause hepatic damage. Fisetin has wide pharmacological effects such as anticancer, antiinflammatory and antioxidant. We aimed to evaluate the possible protective effect of fisetin on paracetamol-induced hepatotoxicity. Fisetin was administered at 25 and 50 mg/kg doses. Paracetamol was administered orally at a dose of 2 g/kg for induce hepatotoxicity 1 h after the fisetin and NAC treatments. The rats were sacrificed 24h after the Paracetamol administration. Tumor necrosis factor-alpha (TNF-α), NFκB and CYP2E1 mRNA levels and Superoxide dismutase (SOD) activity, glutathione (GSH) and malondialdehyde (MDA) levels of livers were determined. Serum ALT, AST and ALP levels were measured. Histopathological examinations were also performed. Fisetin administration significantly decreased the ALT, AST and ALP levels in a dose dependent manner. In addition, SOD activity and GSH levels increased, and the MDA level decreased with the treatment of fisetin. The TNF-α, NFκB and CYP2E1 gene expressions were significantly lower in both doses of the fisetin groups compared with the PARA group. Histopathological examinations showed that fisetin has hepatoprotective effects. This study showed that fisetin has the liver protective effects by increasing GSH, decreasing inflammatory mediators and CYP2E1.

Toxic effect of carpet dust on the biochemical indices and histological structure of the lung in rats: the potential role of cytochrome P450 2E1 and extracellular signal-regulated kinase/mitogen-activated protein kinase pathways.

Background: Carpet dust exposure in the carpet industry causes various respiratory hazards that lead to permanent loss of lung function. This study investigated the potentially toxic effects of knotted and tufted carpet dust on rat lungs and the possible involvement of cytochrome P450 2E1 (CYP2E1) and extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK/MAPK) pathways in the induced toxicity, as well as histological changes in the lung induced by carpet dust.Methods: This study divided 48 adult rats into six groups: group I was the control group, group II (vehicle group) received phosphate buffer saline (50 µL/rat), groups III and IV received knotted dust (2.5 and 5 mg/kg, respectively), and groups V and VI received tufted dust (2.5 and 5 mg/kg, respectively). All treatments were intranasally administered once a day for 7 days.Results: Both dust types significantly decreased the lung content of GSH compared with the control. Significantly elevated malondialdehyde (MDA) and nitric oxide (NO) lung contents were observed with an increased CYP2E1, interleukin (IL)-6, nuclear factor kappa B (NF-κß), and ERK/MAPK. The histological lung structure was moderately affected with a moderately increased number of CD68-positive macrophages in the lung parenchyma of knotted dust-exposed rats, whereas tufted dust exposure severely affected the lung tissue with significantly increased CD68-positive macrophages.Conclusions: Carpet dust exposure could induce oxidative stress and inflammatory response in the lung tissue via induction of CYP2E1 that stimulates ERK/MAPK signalling pathway proteins, resulting in elevated MDA, NO and IL-6 levels in the lung tissue with suppressed GSH content. Tufted dust could possess a more toxic response than knotted ones.

Four Different Structural Dietary Polyphenols, Especially Dihydromyricetin, Possess Superior Protective Effect on Ethanol-Induced ICE-6 and AML-12 Cytotoxicity: The Role of CYP2E1 and Keap1-Nrf2 Pathways.

Polyphenols have received attention as dietary supplements for the relief of alcoholic liver disease (ALD) due to various bioactivities. Ethanol-induced rat small intestinal epithelial cell 6 (IEC-6) and alpha mouse liver 12 (AML-12) cell models were pretreated with four dietary polyphenols with different structures to explore their effects on cytotoxicity and potential protective mechanisms. The results showed that polyphenols had potential functions to inhibit ethanol-induced AML-12 and IEC-6 cell damage and oxidative stress, and restore ethanol-induced IEC-6 permeability and tight junction gene expression. Especially, dihydromyricetin (DMY) had the best protective effect on ethanol-induced cytotoxicity, followed by apigenin (API). Western blot results showed that DMY and API had the best ability to inhibit CYP2E1 and Keap1, and promote nuclear translocation of Nrf2, which might be the potential mechanism by which DMY and API attenuate ethanol-induced cytotoxicity. Moreover, the molecular docking results predicted that DMY and API could bind more tightly to the amino acid residues of CYP2E1 and Keap1, which might be one of the inhibitory modes of dietary polyphenols on CYP2E1 and Keap1. This study provided a rationale for the subsequent protective effect of dietary polyphenols on alcohol-induced liver injury in animal models and provided new clues on bioactive components for ALD-protection based on the gut-liver axis.

Naringenin protects hepato-renal tissues against antituberculosis drugs induced toxic manifestations by modulating interleukin-6, insulin like growth factor-1, biochemical and ultra-structural integrity.

BACKGROUND: The antituberculosis drugs (ATDs), isoniazid, rifampicin, pyrazinamide and ethambutol prompt extreme hepatic and renal damage during treatment of tuberculosis. The present study aimed to investigate protective potential of naringenin against ATDs induced hepato-renal injury. METHODS: Rats were administered with ATDs (pyrazinamide; 210, ethambutol; 170, isoniazid; 85, rifampicin; 65 mg/kg b.wt) orally for 8 weeks (3 days/week) followed by naringenin at three different doses (10, 20 and 40 mg/kg b.wt) conjointly for 8 weeks (3 days/week alternately to ATDs administration) and silymarin (50 mg/kg b.wt) as positive control. RESULTS: Exposure to ATDs caused significant increase in interleukin-6 (IL-6), triglycerides, cholesterol, bilirubin whereas depletion in insulin like growth factor-1 (IGF-1), albumin and glucose in serum. Endogenous antioxidant enzymes glutathione reductase (GR), glutathione peroxidase (GPx) and glucose-6-phosphate-dehydrogenase (G-6-PDH) were diminished in liver and kidney tissues with parallel increase in triglycerides, cholesterol, microsomal LPO and aniline hydroxylase (CYP2E1 enzyme). Ultra-structural observations of liver and kidney showed marked deviation in plasma membranes of various cellular and sub-cellular organelles after 8 weeks of exposure to ATDs. CONCLUSIONS: Conjoint treatment of naringenin counteracted ATDs induced toxic manifestations by regulating IL-6, IGF-1, CYP2E1, biochemical and ultra-structural integrity in a dose dependent manner. Naringenin has excellent potential to protect ATDs induced hepato-renal injury by altering oxidative stress, modulation of antioxidant enzymes, serum cytokines and ultra-structural changes.

[Effects of Gukang Capsules on activity and protein expression of hepatic cytochrome P450 enzymes in rats].

Gukang Capsules are often used in combination with drugs to treat fractures, osteoarthritis, and osteoporosis. Cytochrome P450(CYP450) mainly exists in the liver and participates in the oxidative metabolism of a variety of endogenous and exogenous substances and serves as an important cause of drug-metabolic interactions and adverse reactions. Therefore, it is of great significance to study the effect of Gukang Capsules on the activity and expression of CYP450 for increasing its clinical rational medication and improving the safety of drug combination. In this study, the Cocktail probe method was used to detect the changes in the activities of CYP1A2, CYP3A2, CYP2C11, CYP2C19, CYP2D4, and CYP2E1 in rat liver after treatment with high-, medium-and low-dose Gukang Capsules. The rat liver microsomes were extracted by the calcium chloride method, and protein expression of the above six CYP isoform enzymes was detected by Western blot. The results showed that the low-dose Gukang Capsules could induce CYP3A2 and CYP2D4 in rats, medium-dose Gukang Capsules had no effect on them, and high-dose Gukang Capsules could inhibit them in rats. The high-dose Gukang Capsules did not affect CYP2C11 in rats, but low-and medium-dose Gukang Capsules could induce CYP2C11 in rats. Gukang Capsules could inhibit CYP2C19 in rats and induce CYP1A2 in a dose-independent manner, but did not affect CYP2E1. If Gukang Capsules were co-administered with CYP1A2, CYP2C19, CYP3A2, CYP2C11, and CYP2D4 substrates, the dose should be adjusted to avoid drug interactions.

Treatment with omega-3 PUFAs does not increase the risk of CYP2E1-dependent oxidative stress and diabetic liver pathology.

An increase in CYP2E1 expression is a key factor in the development of diabetic oxidative liver damage. Long-term treatment with omega-3 PUFAs, which are CYP2E1 substrates, may affect CYP2E1 expression in the liver. In this work, we performed Western blot analysis, biochemical methods, and microscopic ultrastructural studies of the liver in a streptozotocin-induced rat model of type 1 diabetes to investigate whether long-term treatment with omega-3 PUFAs could induce CYP2E1-dependent oxidative stress and diabetic liver pathology. Significant hyperglycemia and lack of natural weight gain were observed in the diabetic rats compared to non-diabetic controls. A 2.5-fold increase in CYP2E1 expression (protein content and activity) was also observed in the diabetic rats. In addition, signs of oxidative stress were found in the liver of the diabetic rats. A significant increase in transaminases and GGT level in blood serum was also observed, which could indicate marked destruction of liver tissue. Diabetic dyslipidemia (increased triacylglycerol levels and decreased HDL-C levels) was found. Treatment of the diabetic animals with an omega-3-enriched pharmaceutical composition of PUFAs had no effect on CYP2E1 levels but contributed to a two-fold decrease in enzyme activity. The intensity of lipid peroxidation also remained close to the diabetic group. However, at the same time, antioxidant protection was provided by induction of antioxidant enzyme activity. Examination of the liver ultrastructure revealed no characteristic signs of diabetic pathology. However, omega-3 PUFAs did not normalize blood glucose levels and serum lipid profile. Thus, long-term treatment of diabetic rats with omega-3 PUFAs does not increase the risk of CYP2E1-dependent oxidative stress and development of liver pathology but prevents some diabetic ultrastructural damage to hepatocytes.

Species Difference in the Metabolism of Mulberrin in Vitro and Its Inhibitory Effect on Cytochrome P450 and UDP-Glucuronosyltransferase Enzymes.

This study aimed to evaluate the interspecies difference in metabolism of mulberrin and examine the interaction between mulberrin and CYP enzymes or recombinant human uridine 5'-diphosphate (UDP)-glucuronosyltransferase (UGT) enzymes. Liver microsomes from human (HLMs), Beagle dog (DLMs), minipig (PLMs), monkey (MLMs), rabbit (RLMs), rat (RAMs), and mouse (MIMs) were used to investigate metabolic diversity among different species. Additionally, recombinant human supersomes were used to confirm that metabolic enzymes are involved in the biotransformation of mulberrin. We also evaluated the influence of mulberrin on protein expression by Western blot analysis. Mulberrin metabolism showed significant interspecies differences. We found four and two metabolites in phase I and II reaction systems, respectively. In phase I metabolism profiles of mulberrin for HLMs, PLMs and MLMs conformed to the classic Michaelis-Menten kinetics, RAMs and MIMs followed biphasic kinetics; phase II reaction of mulberrin in HLMs, DLMs, PLMs, MLMs, RLMs, RAMs and MIMs followed biphasic kinetics. UGT1A1 were the major CYP isoforms responsible for the metabolism of mulberrin. Mulberrin showed potent inhibitory effects against CYP3A4, CYP2C9, CYP2E1, UGT1A1, UGT1A3 and UGT2B7 with IC50 values of 54.21, 9.93, 39.12, 3.84, 2.01, 16.36 µM, respectively. According to Western blot analysis, mulberrin can upregulate the protein expression of CYP2C19, and downregulate the expression levels of CYP3A5 and CYP2C9 in HepG2 cells as concentration increased. The interspecies comparisons can help find other species with metabolic pathways similar to those in humans for future in vivo studies.

Hepatoprotective Effects of Phloridzin against Isoniazid-Rifampicin Induced Liver Injury by Regulating CYP450 and Nrf2/HO-1 Pathway in Mice.

The protective effect of phloridzin (PHL) and its potential mechanism were examined in mice with liver injury induced by isoniazid (INH) and rifampicin (RFP). The mice were randomly divided into normal control group, model group, low (80 mg/kg), medium (160 mg/kg) and high (320 mg/kg) phloridzin-treated groups. After 28 d treatment, blood and liver tissue were collected and analysed. The results revealed that PHL regulated liver function related indicators and reduced the pathological tissue damage, indicating that PHL significantly alleviated the liver injury. Furthermore, the level of CYP450 enzyme, the expression of CYP3A4, CYP2E1, heme oxygenase-1 (HO-1) and nuclear factor erythroid 2-related factor 2 (Nrf2) mRNA and protein were inhibited by PHL. These results indicated that PHL exerts a protecting effect against liver injury induced by combination of RFP and INH. The potential mechanisms may be concerned with the activation of Nrf2/HO-1 signaling pathway containing its key antioxidant enzymes and regulation of CYP3A4 and CYP2E1.

Endoplasmic reticulum-targeted inhibition of CYP2E1 with vitamin E nanoemulsions alleviates hepatocyte oxidative stress and reverses alcoholic liver disease.

Alcoholic liver disease (ALD) is a global healthcare problem and socioeconomic issue that is primarily driven by chronic and/or excessive alcohol consumption. Upon alcohol exposure, parenchymal hepatocytes (HCs) up-regulate endoplasmic reticulum (ER)-localized monooxygenase Cytochrome P450 family 2 subfamily E member 1 (CYP2E1) to accelerate the metabolism of ethanol (EtOH), which concurrently exacerbates the production and accumulation of toxic metabolic intermediates, especially reactive oxygen species (ROS), playing a decisive role in the initiation and perpetuation of alcohol-induced liver injury. ALD patients without timely intervention may develop a spectrum of metabolic and functional disorders in the liver, including hepatic steatosis, hepatitis, fibrosis, and even cirrhosis. However, up to now, there have been no FDA-approved pharmacological or nutritional therapeutics for treating patients with ALD, and an effective amelioration of alcohol-induced hepatotoxicity with satisfactory biosafety is still demanding. In this study, antioxidant Vitamin E-incorporating nanoemulsions modified with ER-targetable small molecule p-dodecylbenzene sulfonamide (p-DBSN) was constructed to load and deliver CYP2E1 inhibitor Clomethiazole (CMZ) to the ER of HCs for site-specific inhibition, which displayed remarkable hepatoprotective effects against chronic alcohol exposure without off-target toxicity, both intravenously injected and orally administrated. Generally, our work may provide a promising nanoplatform for reversing ALD.

Short-Term High-Fat Diet Alters Acetaminophen Metabolism in Healthy Individuals.

BACKGROUND: Acetaminophen is metabolized through a nontoxic sulfation and glucuronidation pathway and toxic oxidation pathway (via CYP2E1 and CYP1A2). A short-term high-fat diet induces alterations in the steatotic liver and may alter hepatic drug enzyme activity. In the case of acetaminophen, these alterations may result in an increased risk of hepatotoxicity. Therefore, this study was conducted to assess the effect of a 3-day hypercaloric high-fat diet on the plasma levels of acetaminophen metabolites. METHODS: Nine healthy subjects participated in this randomized, crossover intervention study. The subjects consumed a regular diet or a regular diet supplemented with 500 mL of cream (1700 kcal) for 3 days and then fasted overnight. After ingesting 1000-mg acetaminophen, the plasma concentration of acetaminophen (APAP) and its metabolites [acetaminophen glucuronide, acetaminophen sulfate, 3-cysteinyl-acetaminophen, and 3-(N-acetyl-L-cystein-S-yl)-acetaminophen, and 3-methoxy-acetaminophen] were measured. RESULTS: The 3-day high-fat diet increased the extrapolated area under the concentration-time curve from 0 to infinity (area under the curve 0-inf ) of APAP-Cys by approximately 20% ( P = 0.02) and that from 0 to 8 hours (area under the curve 0-8 ) of APAP-Cys-NAC by approximately 39% ( P = 0.01). The 3-day high-fat diet did not alter the pharmacokinetic parameters of the parent compound acetaminophen and other metabolites. CONCLUSIONS: A short-term, hypercaloric, high-fat diet increases the plasma levels of the APAP metabolites formed by the oxidation pathway, which may increase the risk of hepatotoxicity.

[Extracts of Poria cocos polysaccharides improves alcoholic liver disease in mice via CYP2E1 and NF-κB inflammatory pathways].

The present study investigated the effect of extract of Poria cocos polysaccharides(PCP) on cytochrome P450 2 E1(CYP2 E1) and nuclear factor κB(NF-κB) inflammatory signaling pathways in alcoholic liver disease(ALD) mice and explored its protective effect and mechanism. Sixty male C57 BL/6 N mice of SPF grade were randomly divided into a control group, a model group, a positive drug group(bifendate, 200 mg·kg~(-1)), and high-(200 mg·kg~(-1)) and low-dose(50 mg·kg~(-1)) PCP groups. Gao-binge mo-del was induced and the mice in each group were treated correspondingly. Liver morphological and pathological changes were observed and organ index was calculated. Serum levels of alanine aminotransferase(ALT) and aspartate aminotransferase(AST) were detected. Malondialdehyde(MDA) and superoxide dismutase(SOD) in liver tissues were detected by assay kits. The levels of interleukin-6(IL-6) and tumor necrosis factor-α(TNF-α) were detected by ELISA. The activation of macrophages was observed by immunofluorescence staining and protein expression of CYP2 E1, Toll-like receptor 4(TLR4), NF-κB p65, and phosphorylated NF-κB p65(p-NF-κB p65) were analyzed by Western blot. The ALD model was properly induced. Compared with the model group, the PCP groups significantly improved the pathological injury of liver tissues. Immunofluorescence staining revealed that compared with the model group, the groups with drug intervention showed decreased macrophages in liver tissues. Additionally, the PCP groups showed reduced ALT, AST, MDA, IL-6, and TNF-α(P<0.05), and potentiated activity of SOD(P<0.01). PCP extract has the protective effect against alcoholic liver injury in mice, and the underlying mechanism may be related to the regulation of the expression of CYP2 E1 and inhibition of TLR4/NF-κB inflammatory signaling pathway to reduce oxidative stress and inflammatory injury, thereby inhibiting the development of ALD.

Exploring the Interactome of Cytochrome P450 2E1 in Human Liver Microsomes with Chemical Crosslinking Mass Spectrometry.

Aiming to elucidate the system-wide effects of the alcohol-induced increase in the content of cytochrome P450 2E1 (CYP2E1) on drug metabolism, we explored the array of its protein-protein interactions (interactome) in human liver microsomes (HLM) with chemical crosslinking mass spectrometry (CXMS). Our strategy employs membrane incorporation of purified CYP2E1 modified with photoreactive crosslinkers benzophenone-4-maleimide and 4-(N-succinimidylcarboxy)benzophenone. Exposure of bait-incorporated HLM samples to light was followed by isolating the His-tagged bait protein and its crosslinked aggregates on Ni-NTA agarose. Analyzing the individual bands of SDS-PAGE slabs of thereby isolated protein with the toolset of untargeted proteomics, we detected the crosslinked dimeric and trimeric complexes of CYP2E1 with other drug-metabolizing enzymes. Among the most extensively crosslinked partners of CYP2E1 are the cytochromes P450 2A6, 2C8, 3A4, 4A11, and 4F2, UDP-glucuronosyltransferases (UGTs) 1A and 2B, fatty aldehyde dehydrogenase (ALDH3A2), epoxide hydrolase 1 (EPHX1), disulfide oxidase 1α (ERO1L), and ribophorin II (RPN2). These results demonstrate the exploratory power of the proposed CXMS strategy and corroborate the concept of tight functional integration in the human drug-metabolizing ensemble through protein-protein interactions of the constituting enzymes.

Extracts of Poria cocos polysaccharides improves alcoholic liver disease in mice via CYP2E1 and NF-κB inflammatory pathways / 中国中药杂志

The present study investigated the effect of extract of Poria cocos polysaccharides(PCP) on cytochrome P450 2 E1(CYP2 E1) and nuclear factor κB(NF-κB) inflammatory signaling pathways in alcoholic liver disease(ALD) mice and explored its protective effect and mechanism. Sixty male C57 BL/6 N mice of SPF grade were randomly divided into a control group, a model group, a positive drug group(bifendate, 200 mg·kg~(-1)), and high-(200 mg·kg~(-1)) and low-dose(50 mg·kg~(-1)) PCP groups. Gao-binge mo-del was induced and the mice in each group were treated correspondingly. Liver morphological and pathological changes were observed and organ index was calculated. Serum levels of alanine aminotransferase(ALT) and aspartate aminotransferase(AST) were detected. Malondialdehyde(MDA) and superoxide dismutase(SOD) in liver tissues were detected by assay kits. The levels of interleukin-6(IL-6) and tumor necrosis factor-α(TNF-α) were detected by ELISA. The activation of macrophages was observed by immunofluorescence staining and protein expression of CYP2 E1, Toll-like receptor 4(TLR4), NF-κB p65, and phosphorylated NF-κB p65(p-NF-κB p65) were analyzed by Western blot. The ALD model was properly induced. Compared with the model group, the PCP groups significantly improved the pathological injury of liver tissues. Immunofluorescence staining revealed that compared with the model group, the groups with drug intervention showed decreased macrophages in liver tissues. Additionally, the PCP groups showed reduced ALT, AST, MDA, IL-6, and TNF-α(P<0.05), and potentiated activity of SOD(P<0.01). PCP extract has the protective effect against alcoholic liver injury in mice, and the underlying mechanism may be related to the regulation of the expression of CYP2 E1 and inhibition of TLR4/NF-κB inflammatory signaling pathway to reduce oxidative stress and inflammatory injury, thereby inhibiting the development of ALD.

Pharmacokinetics of isoniazid in Wistar rats exposed to ethanol

Abstract Tuberculosis treatment consists of a drug combination, where isoniazid is the core drug and alcoholism is a factor highly related to poor patient compliance with the therapy. CYP2E1 is an enzyme involved both in the metabolism of ethanol and in the formation of hepatotoxic compounds during the metabolism of isoniazid. The shared metabolism pathway accounts for the possibility of pharmacokinetic interaction in cases of concomitant alcohol use during tuberculosis treatment. The aim of this study was to evaluate the effect of repeated exposure of Wistar rats (males, 250 g, n=6) to ethanol on the pharmacokinetics of a single dose of isoniazid in combination with pyrazinamide and rifampicin (100 mg/kg, 350 mg/kg and 100 mg/kg, respectively). An animal group received the combination of drugs and ethanol and was compared to a control group, which received the combination of drugs without exposure to ethanol. The plasma concentrations of isoniazid were determined by a UHPLC/UV bioanalytical method that was previously validated. Biochemical markers of liver function were measured to assess potential damage. A lower elimination half-life of isoniazid was observed in the ethanol group than in the control group (t1/2 0.91 h versus 1.34 h). There was no evidence of hepatotoxicity through the biomarker enzymes evaluated. The results allow us to infer that although there are no biochemical changes related to liver damage, there is a slight influence of ethanol exposure on the pharmacokinetic profile of isoniazid. This change may have a relevant impact on the efficacy of isoniazid in the outcome of tuberculosis treatment.