P450 2E1 Expression Research Articles

Hepatoprotective Effect of Carob Pulp Flour (Ceratonia siliqua L.) Extract Obtained by Optimized Microwave-Assisted Extraction.

To examine antioxidant capacity and the hepatoprotective effect of carob pulp flour, microwave-assisted extraction was performed. The influence of ethanol concentration (0–40% w/w), extraction time (5–25 min) and irradiation power (400–800 W) on DPPH, FRAP and ABTS antioxidant activity of carob pulp flour extract was evaluated. The strongest influence was that of the ethanol concentration, followed by extraction time. Optimal process parameters for maximizing total antioxidant activity were determined, using response surface methodology: ethanol concentration 40%, time 25 min and power 800 W. Carob extract obtained at optimal conditions (CE) was analyzed in vivo using a paracetamol-induced hepatotoxicity model in mice. Treatment with CE attenuated the parameters of liver injury, especially aspartate and alanine aminotransferase activity, and prevented paracetamol-induced increase in malondialdehyde levels. Pretreatment with CE reversed the activities of superoxide dismutase, catalase, glutathione peroxidase and glutathione S-transferase enzymes after the high dose of paracetamol in the liver. Hepatotoxicity induced using a toxic dose of paracetamol was also seen through histopathological alterations, which were significantly reduced in the groups treated with CE prior to paracetamol. Still, the number of Kupffer cells and macrophages did not differ among groups. Finally, pretreatment of mice with CE and paracetamol significantly decreased the expression of cytochrome P450 2E1 (CYP2E1) in hepatocytes.

Orientin reverses acetaminophen-induced acute liver failure by inhibiting oxidative stress and mitochondrial dysfunction

Oxidative stress, as an important pathogenic factor, plays a critical role in acetaminophen (APAP) overdose-induced acute liver failure (ALF). Thus, an antioxidative strategy may be a good way to alleviate APAP-induced liver damage. Previous research has reported that Orientin (Ori) possesses antioxidant, anti-inflammatory and anticancer effects. This study aimed to explore whether Ori can protect against APAP-induced oxidative stress and to elucidate its underlying mechanism. Our results indicated that Ori alleviated APAP-induced hepatic pathological changes by reducing mouse mortality, inhibiting the expression of cytochrome P450 2E1 (CYP2E1), maintaining a normal liver structure, and reducing the levels of serum alanine transaminase (ALT) and serum aspartate aminotransferase (AST). Moreover, Ori protected against APAP-induced oxidative damage by decreasing the formation of malondialdehyde (MDA) and myeloperoxidase (MPO) and increasing the levels of superoxide dismutase (SOD) and the GSH-to-GSSG ratio. Moreover, Ori regulated APAP-induced hepatocyte apoptosis and mitochondrial dysfunction by inhibiting cytochrome c mitochondrial translocation and c-jun N-terminal kinase phosphorylation, promoting Bcl-2 expression and reducing Bax and caspase-3 cleavage. Furthermore, Ori not only obviously promoted Nrf2 nuclear translocation but also activated the antioxidant-related proteins HO-1, GCLC, GCLM and NQO1. Therefore, Ori prevented APAP-induced hepatocyte oxidative damage and mitochondrial dysfunction via Nrf2-mediated and JNK/cytochrome c/caspase-3 signaling pathways.

Diallyl disulfide prevents 1,3-dichloro-2-propanol-induced hepatotoxicity through mitogen-activated protein kinases signaling

We investigated whether diallyl disulfide (DADS) has protective effects against 1,3-dichloro-2-propanol (1,3-DCP)-induced hepatotoxicity and oxidative damage in rats and HepG2 cells. DADS was administered to rats once daily for 7 days at doses of 30 and 60 mg/kg/day. One hour after the final DADS treatment, the rats were administered 90 mg/kg 1,3-DCP to induce acute hepatotoxicity. DADS treatment significantly suppressed the increase in serum aminotransferase levels induced by 1,3-DCP administration, and reduced histopathological alterations in the liver. DADS treatment reduced 1-3-DCP-induced apoptotic changes in the liver, as revealed by terminal deoxynucleotidyl transferase dUTP nick end labeling staining and immunohistochemistry for caspase-3. DADS treatment competitively inhibited or reduced cytochrome p450 2E1 (CYP2E1) expression, which is involved in the metabolic activation of 1,3-DCP, and enhanced antioxidant properties. Furthermore, DADS treatment inhibited phosphorylation of mitogen-activated protein kinases (MAPKs) and apoptotic signaling. In in vitro experiments, MAPKs inhibitors reduced the expression of Bax/Bcl-2/Caspase 3 signaling, which effects were more significant in co-treated cells with DADS and MAPKs inhibitors. In conclusion, the protective effect of DADS against 1,3-DCP-induced hepatotoxicity may be related to blocking the metabolic activation of 1,3-DCP by suppressing CYP2E1 expression, inducing antioxidant enzyme activity, and reducing apoptotic activity by inhibiting phosphorylation of MAPKs.

Extract of Triticum aestivum Sprouts Suppresses Acetaminophen-Induced Hepatotoxicity in Mice by Inhibiting Oxidative Stress.

Wheat (Triticum aestivum L.) is the oldest known food crop, and many studies have reported that wheat shoots (i.e., wheatgrass) possess anti-cancer, anti-inflammatory, and antioxidant activities. However, the potentially ameliorative effect of wheat shoots on hepatotoxicity caused by high doses of N-acetyl-para-aminophenol (acetaminophen, APAP) has yet to be reported. C57BL/6 mice received daily oral TAE (100 or 200 mg/kg), positive control (silymarin 100 mg/kg), or negative control (saline vehicle) treatments for 7 days prior to intraperitoneal APAP injection. Histological, serum (ELISA), Western blotting, and quantitative PCR analyses of excised liver tissues were then performed. Pre-treatment with TAE (100 or 200 mg/kg) ameliorated APAP-induced pathological damage (i.e., hepatotoxic lesions), reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, and also ameliorated APAP-induced increases in oxidative stress, thereby inhibiting oxidative liver damage and reducing the expression of inflammatory cytokines. In addition, TAE pre-treatment inhibited the expression of Cytochrome P4502E1 (CYP2E1), which is a key enzyme in the onset of APAP-induced hepatotoxicity, suppressed the expression of the target proteins regulated by the antioxidant enzyme Nrf2, and suppressed hepatocyte apoptosis. These findings suggest that TAE is an attractive therapeutic candidate that exhibits potential hepatoprotective activity by inhibiting oxidative stress, inflammation, apoptosis, and liver damage.

Drug Repurposing in Alternative Medicine: Sochehwan, a Polyherbal Traditional Korean Digestant, Protects against Alcoholic Steatohepatitis by Regulating Cytochrome P450 2E1 Expression

Sochehwan (SCH) is an herbal prescription from traditional oriental medicine and is currently used to treat digestive ailments. In a previous study, SCH was found to have the potential to attenuate metabolic syndrome (MetS) by activating AMPK and downstream signaling. From the view of drug repurposing, the efficacy of SCH on alcoholic liver injury is implied in classic medical texts but is yet to be proven. C57BL/6J mice were pre-treated with SCH orally for 5 days and challenged by providing a pair-fed Lieber DeCarli diet containing alcohol for 20 days. Hepatic enzyme and triglyceride levels and endoplasmic reticulum (ER) stress-related markers were analyzed. Moreover, mitogen-activated protein kinases (MAPKs) and cytochrome P450 2E1 (CYP2E1) levels were determined. CYP2E1-transfected HepG2 cells were used to test the cytoprotective efficacy of SCH against the adverse effects of alcohol in vitro. In mice, SCH administration notably reduced hepatic enzyme activity and neural lipid levels. Furthermore, ER-stress markers and MAPK phosphorylation were reduced due to ROS suppression, which was attributed to decreased CYP2E1 expression in liver tissue. In addition, SCH successfully protected CYP2E1-transfected HepG2 cells against ethanol. Our findings suggest SCH attenuated alcohol-induced liver injury by inhibiting CYP2E1 expression and indicate drug repurposing should be considered as a valuable option for drug development in traditional herbal medicines.

Protective effects of tea extracts against alcoholic fatty liver disease in mice via modulating cytochrome P450 2E1 expression and ameliorating oxidative damage.

The alcoholic fatty liver disease (AFLD) has been a severe public health problem. Oxidative stress is involved in the initiation and progression of AFLD. Tea is a popular beverage worldwide with strong antioxidant activity. In this research, our purpose is to explore and compare the effects of 12 selected teas on AFLD. The ethanol liquid diet was used to feed the mice, and 12 tea extracts were administrated at 200 mg/kg body weight every day for 4 weeks. The results showed that the application of several tea extracts exhibited different inhibitory effects on lipid accumulation induced by sub‐acute alcohol consumption based on the determination of triglyceride concentration and the histological alteration in the liver. In addition, several teas significantly decreased serum alanine aminotransferase and aspartate aminotransferase activities, inhibited the cytochrome P450 2E1 expression, and promoted alcohol metabolism (p < .05). Besides, compared with the model group, several teas obviously elevated superoxide dismutase and glutathione peroxidase activities as well as glutathione content, and remarkably decreased malondialdehyde level (p < .05). In general, Fried Green Tea, Fenghuang Narcissus Oolong Tea, and Pu‐erh Dark Tea possessed potential preventive effects on AFLD. Moreover, the main phytochemicals in the three tea extracts were determined and quantified via high‐performance liquid chromatography, and the most commonly detected ingredients were catechins and caffeine, which could exert the protective effects on AFLD.

RETRACTED ARTICLE: Chemoprotective Effect of Daphnetin Against Benzene-induced Leukemia via Alteration of CYP2E1.

Leukemia is the overproduction of a large number of immature blood cells entering into the peripheral blood due to the malignancy of blood-forming tissues. The modern treatment mechanisms that are associated with leukemia comprise chemotherapy, allogeneic cell transplantation, and radiation therapy that comes with adverse side effects. Thus, medicinal herbs and their bioactive compounds are gaining more attention nowadays toward the treatment of leukemia, owing to their minimal side effects. The current study was aimed to scrutinize the antileukemic effect of daphnetin against benzene-induced leukemia in rats and explore the underlying mechanism of its action. Benzene was used for the induction of leukemia in experimental rats. The rats were divided into different groups and body weight; hematological parameters, DNA fragmentation, and cell cycle regulatory parameter were also estimated. RT-PCR was used for the estimation of mRNA expression of cytochrome P450 2E1 (CYP2E1), a membrane protein widely found in liver cells. Daphnetin-treated rats showed upregulation of body weight as compared to other groups. Moreover, daphnetin reduced the blasts (67.8%) in leukemic rats. It also altered the hematological parameters such as RBC (69.8%), WBC (54.5%), lymphocytes (47.6%), neutrophils (48.9%), monocytes (44.7%), eosinophils (48.7%), and basophils (43.5%), respectively. Daphnetin-treated rats showed an increased level of proteins p21 and p53 and reduced level of cyclins D1 and E. RT-PCR showed an upregulated mRNA expression of CYP2E1 (48.4%) of the daphnetin-treated group as compared to other groups. The current study shows the antileukemic effect of daphnetin and highlights the possibility of its use in leukemia to minimize the side effect of the usual therapy.

Spatial Reconstruction of the Early Hepatic Transcriptomic Landscape After an Acetaminophen Overdose Using Single-Cell RNA-Sequencing

Abstract An acetaminophen (APAP) overdose is the most common cause of acute liver failure in the United States. A hallmark characteristic of APAP hepatotoxicity is centrilobular necrosis. General, innate mechanisms such as lower amounts of GSH and higher cytochrome P450 2e1 expression in pericentral (PC) hepatocytes are known to contribute to the differences in susceptibility to cell injury between periportal (PP) hepatocytes and PC hepatocytes. Although a sequence of molecular events involving formation of the reactive metabolite N-acetyl-p-benzoquinone imine, GSH depletion, oxidative stress, and c-Jun N-terminal kinase activation define the early cell stress trajectory following APAP exposure, their activation in PC versus PP hepatocytes is not well characterized. By using single-cell RNA-sequencing, we provide the first reconstruction of the early transcriptomic APAP liver lobule after validation of our methodology using human liver single-cell RNA-sequencing data. Two hours after APAP treatment, we find that PP hepatocytes progress along the APAP stress axis to oxidative stress, before resolving injury due to innate and adaptive mechanisms. However, PC hepatocytes continue along this stress axis as indicated by activation of mitogen-activated protein kinase genes, which is absent in PP hepatocytes. We also identify a population of glutamine synthetase enriched PC hepatocytes in close proximity to the central vein, where a stepwise induction of a stress program culminated in cell death. Collectively, these findings elucidate a molecular sequence of events distinguishing the differential response to APAP exposure between PP and PC hepatocytes and identify a subset of uniquely susceptible PC hepatocytes.

Echinacoside alleviates acetaminophen-induced liver injury by attenuating oxidative stress and inflammatory cytokines in mice.

This study evaluates the protective effect of Echinacoside on acute liver toxicity induced by acetaminophen in mice and the mechanism behind it. Echinacoside and N-Acetyl Cysteine were intragastrically administrated for 7 days, and acetaminophen was intraperitoneally injected into mice 1 h after the last treatment on day 7. At the end of the experimental period, histological examination, parameters for the level of oxidative damage, hepatic malondialdehyde, serum pro-inflammatory cytokines (tumor necrosis factor-α, interleukin-6, and interleukin-1β), UDP-glucuronosyltransferases, and sulfotransferases changes were examined using enzyme-linked immunosorbent assay and standard biochemical procedures. The expression of cytochrome P450 2E1 protein was assessed by western blot, followed by in silico molecular docking. Acetaminophen treatment obviously increased the levels of ALT and AST, changed hepatic histopathology, promoted oxidative stress, decreased antioxidant enzyme activities, and elevated the pro-inflammatory cytokines. Echinacoside significantly attenuated Acetaminophen-induced liver damage in a dose-dependent manner, with the most effective dose at 100 mg/kg. The pretreatments of Echinacoside in different concentrations altered the Acetaminophen-induced hepatotoxicity levels by decreasing the level of liver enzymes, reducing the liver necrosis with vacuolization, decreasing the hepatic malondialdehyde formation, increasing hepatic antioxidants activities, suppressing the pro-inflammatory cytokines (Tumor Necrosis Factor, Interleukin-6 and Interleukin-1beta), inhibiting Nitric Oxide production, enhancing sulfotransferases and UDP-glucuronosyltransferases activities. Notably, the expression of cytochrome P450 2E1 was inhibited by Echinacoside in a dose-dependent manner and the binding energy was -214.3 MeV. Echinacoside showed a significant protective effect against Acetaminophen-induced hepatotoxicity through the inhibition of oxidative stress, the expression of pro-inflammatory cytokines and cytochrome P450 2E1 protein expression.

Propolis alleviates 4‐aminobiphenyl‐induced oxidative DNA damage by inhibition of CYP2E1 expression in human liver cells

4-Aminobiphenyl (4-ABP) may cause DNA damage in human liver cells (HepG2 and L-02). Propolis exhibits antioxidant properties through reactive oxygen species (ROS) scavenging. We determined the effects of propolis in alleviating 4-ABP -induced DNA damage using the comet assay. Results revealed that propolis could significantly alleviated oxidative damaged DNA by 4-ABP. Furthermore, we proved that inhibition of cytochrome P450 2E1 (CYP2E1) expression by propolis could contribute to the decreased oxidative DNA damage in the treated cells, as the conversion of 4-ABP into its metabolite, N-hydroxy-ABP (HOABP), was blocked; after all, HOABP showed more genotoxic than its parent chemical, 4-ABP. With the homologous recombination assay, propolis failed to induce DNA repair enzymes. Furthermore, the expression of RAD51, Ku70/Ku80, and OGG1 in treated cells were determined with the western blot, revealing that the expression of these protein were unchanged in comparison with those in nontreated cells. However, propolis could protect the treated cells from DNA damage. In conclusion, propolis could antagonize 4-ABP-induced oxidative DNA damage though the removal of ROS and inhibition of CYP2E1 expression in the treated cells.

Inhibitory Effect of Thai Purple Rice Husk Extract on Chemically Induced Carcinogenesis in Rats.

This study investigated the cancer chemopreventive effects of an acidic methanol extract of purple rice husk on chemically induced carcinogenesis in rats. This purple rice husk extract (PRHE) had high polyphenol contents. Vanillic acid was a major phenolic compound in PRHE. Three major anthocyanins found in PRHE were malvidin-3-glucoside, peonidin-3-glucoside and cyanidin-3-glucoside. PRHE was not toxic and clastogenic in rats. The LD50 of PRHE was greater than 2000 mg kg−1 body weight (BW). The oral administration of 300 or 1000 mg kg−1 BW of PRHE for 28 days significantly decreased the number of micronucleated hepatocytes in diethylnitrosamine-initiated rats. The inhibitory mechanisms were associated with the reduction of cytochrome P450 2E1 expression and induction of some detoxifying enzymes in the liver. In addition, treatment with 500 mg kg−1 BW of PRHE for eight weeks did not induce preneoplastic lesions in the liver and colon. It significantly inhibited hepatic glutathione-S-transferase positive foci formation induced by diethylnitrosamine and 1,2-dimethylhydrazine by suppression of hepatocyte proliferation and induction of apoptosis. In conclusion, PRHE did not present toxicity, clastogenicity or carcinogenicity in rats. It exhibited cancer chemopreventive properties against chemically induced early stages rat hepatocarcinogenesis. Anthocyanins and vanillic acid might be candidate anticarcinogenic compounds in purple rice husk.

A New Perspective on Fish Oil: The Prevention of Alcoholic Liver Disease.

The mechanisms of alcoholic liver diseases (ALD) are very complex and interrelated, including abnormal lipid metabolism, oxidative stress, and gut-derived endotoxin pathway. On the other hand, fish oil is rich in n-3 polyunsaturated fatty acids (PUFAs), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which decrease blood triglyceride concentration in hypertriglycemia patients and show protective effects against fatty liver. However, there is limited evidence from studies of the relationship between fish oil and ALD based on the viewpoint of the intestinal integrity and microflora. Therefore, this review discusses the mechanism of amelioration for ALD by fish oil. Based on our previous studies, partial replacement of olive oil by fish oil in alcohol-containing liquid diet ameliorated the liver damage including fatty liver and inflammation in rats. Based on these results, the mechanisms of hepatoprotective effects due to fish oil substitution were discussed in three parts, such as regulating lipid metabolism, decreasing oxidative stress and maintaining intestinal health. First of all, we found that fish oil substitution increased plasma adiponectin levels, and then increasing MCAD and CPT-1 mRNA levels to accelerate fatty acid oxidation in liver, then further prevent ethanol-induced hepatosteatosis in rats with chronic alcohol-feeding. Fish oil replacement also enhanced hepatic autophagy flux, which enhanced lipid degradation, then inhibited lipid accumulation in liver. Secondly, the appreciable proportion of fish oil decreased lipid peroxidation by reducing the protein expression of cytochrome p450 2E1 in chronic alcohol-feeding rats. We also speculated that the appropriate proportion of n-6 and n-3 PUFAs is very important for preventing alcoholic liver disease. At last, substituting fish oil for olive oil normalized the intestinal permeability and fecal microbiota composition, thus providing a low plasma endotoxin level and inflammatory responses, which exert ameliorative effects on ethanol-induced liver injuries in rats.

Effects of Different Green Tea Extracts on Chronic Alcohol Induced-Fatty Liver Disease by Ameliorating Oxidative Stress and Inflammation in Mice.

Alcoholic fatty liver disease (AFLD) is a common chronic liver disease and has become a critical global public health problem. Green tea is a popular drink worldwide and contains several bioactive compounds. Different green teas could contain diverse compounds and possess distinct bioactivities. In the present study, the effects of 10 green teas on chronic alcohol induced-fatty liver disease in mice were explored and compared. The results showed that several green teas significantly reduced triacylglycerol levels in serum and liver as well as the aminotransferase activities in mice at a dose of 200 mg/kg, suggesting that they possess hepatoprotective effects. Moreover, several green teas remarkably decreased the expression of cytochrome P450 2E1, the levels of malondialdehyde and 4-hydroxynonenoic acid, and the contents of proinflammatory cytokines, indicating that they could alleviate oxidation damage and inflammation induced by chronic alcohol exposure. In addition, Seven Star Matcha Tea and Selenium-Enriched Matcha Tea could increase glutathione level. Furthermore, the main phytochemical components in green teas were determined and quantified by high-performance liquid chromatography, and the correlation analysis showed that gallic acid, gallocatechin, catechin, chlorogenic acid, and epigallocatechin gallate might at least partially contribute to protective effects on AFLD. In conclusion, Selenium-Enriched Chaoqing Green Tea, Xihu Longjing Tea, Taiping Houkui Tea, and Selenium-Enriched Matcha Tea showed the strongest preventive effects on AFLD. This research also provides the public with new insights about the effects of different green teas on AFLD.

Fasting Enhances Biochemical and Histopathological Changes of Isoniazid Induced Liver Injury in Mouse

Fasting can up regulate the expression of cytochrome P450 2E1 and induce glutathione levels to decrease, protecting the liver from hepatotoxic agents. The aim of this study was to research the mechanism of fasting aggravates isoniazid induced liver injury in mouse. 7 w old male C57 black 6 mice were randomly assigned to two groups: mice fed ad libitum on commercial chow (A group) and mice fasted for 12 h during the day and fed ad libitum on commercial chow (F group). All animals were administered with 100 mg/kg of isoniazid daily by gavage for 6 w (isoniazid levels were selected on basis of screening multiple concentrations). Sera were collected to measure biochemical parameters. Liver sections were stained with hematoxylin and eosin to evaluate hepatic histology. Cytokines was detected by cytometric bead array, flow cytometry. Isoniazid administration (100 mg/kg) daily for 6 w did not significantly induce histological damage in mice of A group. Compared with normal mice, there was no significant difference in serum alanine aminotransferase and aspartate aminotransferase. However, the level of alanine aminotransferase and aspartate aminotransferase levels in F group remained elevated for 6 w, reached its peak on the 3rd d and gradually returned to normal. The liver sections revealed hepatic edema around the central vein on the 3rd d. At 1st or 2nd w, hepatic edema around the central vein with inflammatory cell infiltration and focal necrosis was present. After 4 w, liver histology gradually recovered. Fasting condition influences the cytokine concentration in peripheral blood and liver tissue.

Fermentation of Sprouted Ginseng (Panax ginseng) Increases Flavonoid and Phenolic Contents to Attenuate Alcoholic Hangover and Acute Liver Injury in Mice.

Alcoholic liver damage is caused by ethanol and its oxidized intermediates, and endotoxin-induced acute liver failure is mediated by apoptosis and inflammation. We investigated whether extracts of sprouts of Panax ginseng (SG) attenuate alcohol or endotoxin-induced acute liver injury in mice. Whole SG contains eight times more ginsenosides than the root and, because it grows quickly ([Formula: see text]30 days) without using pesticides, the whole-plant can be harvested. The extracts were enriched in phenolics and flavonoids and showed high radical scavenging activities. Mice received oral administration of SG or fermented SG (FSG) extracts 1 h before an injection of either ethanol or lipopolysaccharide and D-galactosamine (LPS/GalN). The latency of righting reflex was monitored to examine the effect of extracts on relieving hangover symptoms. The results indicate that FSG significantly reduced the latency of righting reflex, SG and FSG increased the activity and expression of ethanol-metabolizing enzymes, and FSG decreased hepatic necrosis and plasma levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). During the ethanol metabolism, cytochrome P450 2E1 expression was increased, but 4-hydroxynonenal levels were decreased by the extracts due to their anti-oxidant activity. LPS/GalN-induced liver injury was reduced by SG and FSG; plasma ALT and AST levels, hepatic necrosis, and apoptotic and inflammatory markers were all decreased. In conclusion, SG extracts attenuated ethanol-induced hangover and endotoxin-induced acute liver injury, and fermentation enhanced the efficacy with regard to relieving hangover.

Transfer of hepatocellular microRNA regulates cytochrome P450 2E1 in renal tubular cells.

BackgroundExtracellular microRNAs enter kidney cells and modify gene expression. We used a Dicer-hepatocyte-specific microRNA conditional-knock-out (Dicer-CKO) mouse to investigate microRNA transfer from liver to kidney.MethodsDicerflox/flox mice were treated with a Cre recombinase-expressing adenovirus (AAV8) to selectively inhibit hepatocyte microRNA production (Dicer-CKO). Organ microRNA expression was measured in health and following paracetamol toxicity. The functional consequence of hepatic microRNA transfer was determined by measuring the expression and activity of cytochrome P450 2E1 (target of the hepatocellular miR-122), and by measuring the effect of serum extracellular vesicles (ECVs) on proximal tubular cell injury. In humans with liver injury we measured microRNA expression in urinary ECVs. A murine model of myocardial infarction was used as a non-hepatic model of microRNA release.FindingsDicer-CKO mice demonstrated a decrease in kidney miR-122 in the absence of other microRNA changes. During hepatotoxicity, miR-122 increased in kidney tubular cells; this was abolished in Dicer-CKO mice. Depletion of hepatocyte microRNA increased kidney cytochrome P450 2E1 expression and activity. Serum ECVs from mice with hepatotoxicity increased proximal tubular cell miR-122 and prevented cisplatin toxicity. miR-122 increased in urinary ECVs during human hepatotoxicity. Transfer of microRNA was not restricted to liver injury –miR-499 was released following cardiac injury and correlated with an increase in the kidney.InterpretationPhysiological transfer of functional microRNA to the kidney is increased by liver injury and this signalling represents a new paradigm for understanding the relationship between liver injury and renal function.FundingKidney Research UK, Medical Research Scotland, Medical Research Council.

Phytochemical analysis and hepatoprotective activity of Raphanus sativus var. sativus in Sprague-Dawley rats

Purpose: To determine the phenolic and flavonoid contents of R. sativus rhizome ethanol extract and the hepatoprotective effect of the extract in rats.&#x0D; Methods: Folin–Ciocalteau and aluminum chloride colorimetric tests were used to determine the contents of phenols and flavonoids in the R. sativus extract. Male Sprague-Dawley rats induced with CCl4 to develop hepatotoxicity were treated orally with R. sativus extract for 4 weeks. The antioxidant and anti-inflammatory effects of the extract on the liver were determined by evaluating the concentration of oxidative analytes, serum liver enzymes and lipids, and hepatic histopathology and cytochrome P450 2E1 expression.&#x0D; Results: R. sativus extract significantly (p &lt; 0.05) reduced the hepatotoxic effect of CCl4 via its antioxidant activities and protection of liver tissues from oxidative damage.&#x0D; Conclusion: The hepatoprotective effects of R. sativus rhizome ethanol extract are attributed to its highphenolic and flavonoid contents.&#x0D; Keywords: R. savitus rhizome, Phenols, Flavonoid contents, antioxidant, Hepatoprotective

β-Sitosterol attenuates liver injury in a rat model of chronic alcohol intake.

Liver disease associated with long-term drinking is one of the leading causes of death. There is an urgent need for more effective drugs to reduce alcoholic liver damage. Yin Chen Hao, a traditional Chinese herbal medicine, is widely used for liver diseases. Here, we aimed to explore the protective effect of β-sitosterol (the active ingredient of Artemisia spp.) on alcoholic liver injuries. We treated the rats with alcohol and different dosages of β-sitosterol to detect the expression levels of liver function indicators in serum. The functions of β-sitosterol were evaluated based on variations in histology, liver function indicators and DNA oxidative damages. The underlying mechanism was investigated by measuring lipid peroxidation, the antioxidant, the expression of cytochrome P450 2E1 and the expression of apoptosis related genes. The results showed that β-sitosterol could improve liver histology and suppress biochemical indicators caused by alcohol in serum. In addition, β-sitosterol alleviates alcohol-induced oxidative stress, such as restoring erythrocyte membrane fluidity, reducing glutathione depletion, restoring antioxidant enzyme activity and reducing malondialdehyde overproduction. Furthermore, β-sitosterol downregulated the expression of apoptosis-related genes through the PI3K/Akt pathway. In conclusion, β-sitosterol has a protective effect on chronic alcoholism and has broad clinical application prospects in the treatment of alcohol-induced liver damage.

Involvement of CYP2E1-ROS-CD36/DGAT2 axis in the pathogenesis of VPA-induced hepatic steatosis in vivo and in vitro

Valproic acid (VPA) is a widely prescribed antiepileptic drug, which may cause steatosis in the liver. Oxidative stress is associated with the progression of VPA-induced hepatic steatosis. However, the potential mechanisms are not fully understood. In this study, we demonstrated the involvement of CYP2E1-ROS-CD36/DGAT2 axis in the pathogenesis of VPA-induced hepatic steatosis in vitro and in vivo. First, VPA treatment (500 mg/kg in mice, 5 mM in LO2 cells) induced hepatic steatosis and enhanced reactive oxidative stress (ROS) level, and ROS scavenger, N-acetyl-L-cysteine (NAC, 200 mg/kg in mice, 1 mM in LO2 cells) reversed the changes. Next, we observed the enhanced expression and enzymatic activity of cytochrome P450 2E1 (CYP2E1) in VPA-treated mice and LO2 cells. Importantly, VPA-induced ROS accumulation and hepatic steatosis were attenuated when CYP2E1 was inhibited using CYP2E1 inhibitor, diallyl sulfide (DAS, 100 mg/kg in mice, 1 mM in LO2 cells) or in CYP2E1-knockdown cell line, suggesting that CYP2E1 plays a potential role in ROS production following hepatic steatosis. Furthermore, gene expression analysis showed that the mRNA levels of cluster of differentiation 36 (CD36), a fatty acid translocase protein and distinct diacylglycerol acyltransferase 2 (DGAT2) were significantly upregulated in mice and LO2 cells after VPA treatment, while the change was alleviated by NAC and DAS. Meanwhile, time course experiments demonstrated that the increase of CYP2E1 level occurred earlier than that of ROS, CD36 and DGAT2, and ROS generation preceded the onset of hepatic steatosis. Taken together, VPA treatment enhances the expression and enzymatic activity of CYP2E1, which promotes ROS production and then causes CD36 and DGAT2 overproduction and hepatic steatosis in mice and LO2 cells, which provides a novel insight into VPA-induced hepatic steatosis.

Salidroside protects mice against CCl4-induced acute liver injury via down-regulating CYP2E1 expression and inhibiting NLRP3 inflammasome activation

Salidroside (Sal), a natural phenolic compound isolated from Rhodiola sachalinensis, has been utilized as anti-inflammatory and antioxidant for centuries, however, its effects against liver injury and the underlying mechanisms are unclear. This study was designed to evaluate the protective effects and underlying mechanisms of Sal on carbon tetrachloride (CCl4)-induced acute liver injury (ALI) in mice. C57BL/6 mice were pretreated with Sal before CCl4 injection, the serum and liver tissue were collected to evaluate liver damage and molecular indices. The results showed that Sal pretreatment dose-dependently attenuated CCl4-induced acute liver injury, as indicated by lowering the activities of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT), and inhibiting hepatic pathological damage and apoptosis. In addition, Sal alleviated CCl4-primed oxidative stress and inflammatory response by restoring hepatic glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), and inhibiting cytokines. Finally, Sal also down-regulated the expression of cytochrome P4502E1 (CYP2E1), and Nod-like receptor protein 3 (NLRP3) inflammasome activation in the liver of mice by CCl4. Our study demonstrates that Sal exerts its hepatoprotective effects on ALI through its antioxidant and anti-inflammatory effects, which might be mediated by down-regulating CYP2E1 expression and inhibiting NLRP3 inflammasome activation.