P450 2E1 Protein Research Articles

Valorization of broiler edible byproducts: a chicken-liver hydrolysate with hepatoprotection against binge drinking

Over 10,000 metric-ton broiler livers are produced annually in Taiwan. Concerning unpleasant odor and healthy issue, broiler livers are not attractive to consumers. Although the patented chicken-liver hydrolysates (CLHs) through pepsin digestion possess several biofunctionalities, there is no study on hepatoprotection of CLH-based formula capsule (GBHP01) against binge drinking (Whiskey, 50% Alc./Vol.). GBHP01 led to an accelerated blood-alcohol clearance in rats, as evidenced by lowering blood-alcohol increment within 0 to 4 h, increasing blood-alcohol decrement within 4 to 8 h, and smaller blood alcohol concentration areas under the curve (BAC AUC) in the 8-h period (p < 0.05). The ameliorative effects of GBHP01 against binge drinking in rats over 6 wk were attributed to accelerated alcohol metabolism by further increasing alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) activities while downregulating cytochrome P450 2E1 (CYP2E1) protein expression, elevating antioxidant capacity, decreasing zonula occludens-1 (ZO-1) protein decrement and serum endotoxin, and reducing inflammation related protein levels, that is, toll-like receptor 4 (TLR4) and mitogen-activated protein kinase (MAPK), and proinflammatory cytokines. The development of CLH supplements could not only enhance the added value of broiler livers through nutraceutical development but also offer a strategy to maximize the utilization of poultry processing residues, as shown in this study.

Biphasic effects of ethanol consumption on N,N-dimethylformamide-induced liver injury in mice

N,N-Dimethylformamide (DMF) is a well-documented occupational hazardous material, which can induce occupational liver injury. The current study was designed to investigate whether ethanol consumption can affect DMF-induced hepatotoxicity and the potential underlying mechanisms involved. We found that a single dose of ethanol (1.25, 2.5, or 5 g/kg bw by gavage) significantly repressed the increase in serum alanine transaminase (ALT) and aspartate transaminase (AST) activities and alleviated the liver histopathological changes in mice challenged with 3 g/kg DMF. In contrast, long-term moderate drinking (2.5 g/kg bw) significantly aggravated the repeated DMF (0.7 g/kg bw) exposure-induced increase in the serum ALT and AST activities. Mechanistically, acute ethanol consumption suppressed DMF-induced activation of the NLR family pyrin domain-containing protein 3 (NLRP3) inflammasome, while long-term moderate ethanol consumption promoted hepatocyte apoptosis in the mouse liver. Notably, cytochrome P4502E1 (CYP2E1) protein level and activity in mouse livers were not significantly affected by ethanol per se in the two models. These results confirm that regular drinking can increase the risk of DMF-induced hepatotoxicity, and suggest that DMF-handling workers should avoid consuming ethanol to reduce the risk of DMF-indued liver injury.

The Preliminary Results for Evaluating Cocoa Butter's Hepatoprotective Effects against Lipid Accumulation and Inflammation in Adult Male Rats Chronically Fed Ethanol.

The purpose of this study was to clarify the role of saturated fats from cocoa butter (plant source) compared with lard (animal source) on alcoholic liver damage in rats. Male Wistar rats were fed either a control diet (C) or an ethanol diet (E), and the dietary fats (corn oil, olive oil, and safflower oil) of these two diets were further replaced by lard (CL, EL) or cocoa butter (CC, EC). After 8-week feeding, plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities, hepatic triglyceride (TG) levels, plasma intercellular adhesion molecular (ICAM)-1 levels, hepatic cytochrome P450 2E1 (CYP2E1) protein expression, and hepatic interleukin (IL)-1β significantly increased in the E group compared to the C group. In addition, hepatic histopathological scores of fatty changes, inflammatory cell infiltration, and degeneration and necrosis in the E group were significantly higher compared to those in the C group. However, fatty changes were significantly inhibited only in the EC group as well as hepatic inflammatory cell infiltration, degeneration, and necrosis being significantly lower in the EL and EC groups. Plasma ICAM-1 and hepatic tumor necrosis factor (TNF)-α, IL-1β, IL-6, and IL-10 levels were significantly lower in the EL and EC groups than those in the E group. Moreover, a correlation analysis showed that hepatic histopathological scores of degeneration and necrosis were significantly positively correlated with erythrocytic oleic acid (C18:1) and were negatively correlated with linoleic acid (C18:2). In conclusion, cocoa butter protected the liver against lipid accumulation and inflammation in rats chronically fed ethanol.

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.

Purified anthocyanins from Zea mays L. cob ameliorates chronic liver injury in mice via modulating of oxidative stress and apoptosis

Purple corn (Zea mays L.) is one of the main economic crops in China and has been used in the treatment of cystitis, urinary infections and obesity. However, purple corncobs, the by-product remaining after processing and having an intense purple-black color, are normally disposed of as waste or used as animal feed. Therefore, to further expand the medicinal value of purple corncob, its content was analyzed and, after purification, the effect and mechanism of purified purple corncob anthocyanins (PPCCA) on CCl4 -induced chronic liver injury in mice were investigated. It was observed that the total anthocyanin content (TAC) from PPCCA (317.51 ± 9.30 mg cyanidin 3-O-glucoside (C-3-G)g-1 dry weight) was significantly higher than that from the purified purple corn seed anthocyanin (266.73 ± 3.67 mg C-3-G g-1 dry weight), of which C-3-G accounted for 90.6% and 90.4% of the TAC, respectively. Furthermore, compared with the CCl4 group, PPCCA treatment significantly reduced liver index, serum total bilirubin, alanine transaminase, aspartate transaminase and liver malondialdehyde levels, but increased liver superoxide dismutase activity. The pathological changes were also improved, such as more regular arrangement of hepatocytes, less swelling, and fewer vacuoles and apoptotic cells. Additionally, mechanistic studies showed that PPCCA downregulated the expression of Caspase-3, Bax and cytochrome P450 2E1 proteins in the liver and upregulated the expression of Bcl-2. These results demonstrated that PPCCA could ameliorate CCl4 -induced chronic liver injury by regulating oxidative stress and hepatocyte apoptosis pathways. © 2021 Society of Chemical Industry.

In Silico Approach for Hepatoprotective Activity of Piper crocatum Leaf toward Cytochrome P450 2E1 Protein

In Silico Approach for Hepatoprotective Activity of Piper crocatum Leaf toward Cytochrome P450 2E1 Protein

Chronic intake of high-dose of blueberry leaf extract does not augment the harmful effects of ethanol in rats.

Excessive alcohol consumption is a risk factor for liver diseases. Enhancement of alcohol metabolism could be an effective strategy to prevent these adverse effects since it promotes the clearance of ethanol and acetaldehyde from the serum. Polyphenol-rich products have shown to protect against alcohol-related liver damage. Blueberry leaves have attracted attention as they are rich polyphenols such as proantocyanidins and chlorogenic acid. In this study, we investigated the effects of a high dose of blueberry leaf extract (BLEx) on alcohol metabolism during chronic intake of ethanol. Seven-week old Sprague-Dawley (SD) rats were divided into four groups: normal liquid diet group (NLD), normal liquid diet + BLEx group (NLD + BLEx), alcohol liquid diet group (ALD), and alcohol liquid diet + BLEx (ALD + BLEx). Then, rats were fed experimental diet for 5 weeks and at the end of feeding period, body weight, food intake, liver weight, indices of liver injury, expression and activity of alcohol metabolism-related and anti-oxidative enzymes, and levels of carbonyl protein, triglyceride (TG), and total cholesterol (T-Chol) were measured. Body weight and food intake decreased, whereas liver aldehyde dehydrogenase (ALDH) activity, liver microsomal cytochrome P450 2E1 (CYP2E1) protein and mRNA expression, and heme oxygenase 1 (HO-1) mRNA expression were upregulated by ethanol intake. Dietary BLEx, however, did not affect any of these ethanol-related changes. Indices of liver injury, expression and activity of other alcohol metabolism-related enzymes, liver carbonyl protein, TG, and T-Chol levels were not altered by ethanol and BLEx. Thus, chronic BLEx intake does not ameliorate the harmful effects of ethanol.

Identification of oxidative stress potential in phenolic compounds and their link to liver injury

The intervention effects of blueberry anthocyanins extract (BAE) on the acrylamide (AA)-induced general toxicity, genotoxicity and reproductive toxicity were investigated in a mice model. Compared to the AA group, BAE restored the AA-induced alteration in haematology and serum chemistry, markedly decreased the DNA damage in lymphocyte and liver cells, as well as micronucleus formation in bone marrow cell. Meanwhile, BAE improved sperm motility levels and decreased abnormal sperm rate. Furthermore, BAE inhibited the AA-induced ROS accumulation and glutathione (GSH) depletion, ameliorated the activities of glutathione peroxidase (GPx) and glutathione-S-transferase (GST), improved the protein expression of GPx, GST and gamma-glutamyl cysteine synthase (γ-GCS), and inhibited the cytochrome P4502E1 (CYP2E1) protein expression. Thus, the intervention mechanism of BAE on the AA-induced toxicity possibly attributed to the prevention of AA-induced oxidative stress and CYP2E1 activation. BAE would have potential application for the chemoprevention of the AA toxicity as a nutraceutical or a dietary supplement.

Evaluation of in vitro/in vivo anti-diabetic effects and identification of compounds from Physalis alkekengi

The aims of the present study were to assess the anti-diabetic effects of Physalis alkekengi L. (PA) in 3T3-L1 pre-adipocyte cells and HepG2-GFP-CYP2E1 (E47) cells and in a pre-diabetic rat model, as well as to identify the active chemical constituents. The in vitro results showed that PA has a strong anti-diabetic capacity to relieve oxidative stress and inhibit α-glucosidase activity. Mechanistic analysis also showed that ethyl acetate extracts of aerial parts and fruit of PA (PAG-EA and PAF-EA) enhanced glucose transporter 4 expression and function as well as enhanced insulin sensitivity by inhibiting the expression of cytochrome P450-2E1 (CYP2E1) mRNA and protein. In vivo, PAG-EA and PAF-EA significantly decreased the levels of fasting blood glucose and fasting insulin, as well as total cholesterol and triglyceride, in the pre-diabetic rats. The results from insulin sensitivity index and homeostasis model assessment-insulin resistance index along with an oral glucose tolerance test also showed that PAG-EA and PAF-EA could significantly enhance the insulin sensitivity, which confirmed the in vitro findings. Moreover, HPLC-ESI-QTOF-MS analysis identified flavonoids, physalins and phenolic acids as the main plant constituents. Our findings support the ethnopharmacological use of PA fruit, along with its aerial parts, as a strong anti-diabetic agent. The EA fraction, especially the constituent polyphenols and flavonoids, may have a good potential to treat diabetes.

Apigenin inhibits ethanol-induced oxidative stress and LPS-induced inflammatory cytokine production in cultured rat hepatocytes

Apigenin is a natural flavonoid compound that has antioxidative, anti-inflammatory, and hepatoprotective effects, but the underlying mechanisms are still unclear. In this study, the effects of apigenin on ethanol-induced oxidative stress and lipopolysaccharide (LPS)-induced inflammatory cytokine production were examined in cultured rat hepatocytes. Following pretreatment of ethanol-stimulated hepatocytes with apigenin 6–24mM for 2h, the levels of cytochrome P450 2E1 (CYP2E1) protein expression and supernatant alanine aminotransferase and malondialdehyde were reduced (P<0.05 or P<0.01), while the activities of glutathione reductase and glutathione peroxidase were increased (P<0.05 or P<0.01). Likewise, the pretreatment of LPS-stimulated hepatocytes with the same concentrations of apigenin could decrease the levels of nuclear factor-κB protein expression and supernatant tumor necrosis factor-α and interleukin-6 (P<0.05 or P<0.01), and increase the level of IκB-α protein expression (P<0.05 or P<0.01). In all of these results, the concentration of 24μM was the most effective. These findings demonstrate that apigenin may exert an inhibitory effect on ethanol-induced oxidative stress and LPS-induced inflammation in the cultured hepatocytes, and its mechanisms may be related to the reduction of CYP2E1 expression, increment of antioxidative ability, and regulation of inflammatory gene expression.

Different Dietary Proportions of Fish Oil Regulate Inflammatory Factors but Do Not Change Intestinal Tight Junction ZO-1 Expression in Ethanol-Fed Rats.

Sixty male Wistar rats were fed a control or an ethanol-containing diet in groups C or E. The fat compositions were adjusted with 25% or 57% fish oil substituted for olive oil in groups CF25, CF57, EF25, and EF57. Hepatic thiobarbituric acid-reactive substance (TBARS) levels, cytochrome P450 2E1 protein expression, and tumor necrosis factor- (TNF-) α, interleukin- (IL-) 1β, IL-6, and IL-10 levels, as well as intracellular adhesion molecule (ICAM)-1 levels were significantly elevated, whereas plasma adiponectin level was significantly reduced in group E (p < 0.05). Hepatic histopathological scores of fatty change and inflammation, in group E were significantly higher than those of group C (p < 0.05). Hepatic TBARS, plasma ICAM-1, and hepatic TNF-α, IL-1β, and IL-10 levels were significantly lower, and plasma adiponectin levels were significantly higher in groups EF25 and EF57 than those in group E (p < 0.05). The immunoreactive area of the intestinal tight junction protein, ZO-1, showed no change between groups C and E. Only group CF57 displayed a significantly higher ZO-1 immunoreactive area compared to group C (p = 0.0415). 25% or 57% fish oil substituted for dietary olive oil could prevent ethanol-induced liver damage in rats, but the mechanism might not be related to intestinal tight junction ZO-1 expression.

Relationship between coumarin-induced hepatocellular toxicity and mitochondrial function in rats

The manifestation of coumarin-induced hepatocellular toxicity may differ and depends on the frequency of administration to rats. A single coumarin dose induces hepatocellular necrosis while repeated doses induce only hepatocyte degeneration. However, the mechanism underlying these effects remains unclear. Therefore, we investigated the mechanism of coumarin-induced hepatotoxicity in rats. Coumarin was administered to male rats as a single dose or for 4 consecutive days, and samples were obtained 4 or 24 h after a single dose or 24 h after the repeated doses. A single coumarin dose significantly induced hepatocellular necrosis in rats; however, toxicity was attenuated after repeated dosing. With a single dose, hepatocellular necrosis was preceded by increased mitochondrial number and size and decreased mitochondrial function. An increased expression of granular cytochrome P450 (CYP) 2E1 protein was observed in the cytoplasm and mitochondria of coumarin-treated rats compared to the expression in the untreated controls. Nevertheless, repeated dosing showed mitochondrial function that was equivalent to that of the control while enlarged CYP2E1 protein droplets were distributed outside the mitochondria. These results suggest that mitochondrial function and CYP2E1 expression might be involved in coumarin-induced hepatocellular toxicity in rats. A reduction in mitochondrial CYP2E1 might be implicated in the acquisition of coumarin resistance after repeated doses.

Blueberry anthocyanins extract inhibits acrylamide-induced diverse toxicity in mice by preventing oxidative stress and cytochrome P450 2E1 activation

The intervention effects of blueberry anthocyanins extract (BAE) on the acrylamide (AA)-induced general toxicity, genotoxicity and reproductive toxicity were investigated in a mice model. Compared to the AA group, BAE restored the AA-induced alteration in haematology and serum chemistry, markedly decreased the DNA damage in lymphocyte and liver cells, as well as micronucleus formation in bone marrow cell. Meanwhile, BAE improved sperm motility levels and decreased abnormal sperm rate. Furthermore, BAE inhibited the AA-induced ROS accumulation and glutathione (GSH) depletion, ameliorated the activities of glutathione peroxidase (GPx) and glutathione-S-transferase (GST), improved the protein expression of GPx, GST and gamma-glutamyl cysteine synthase (γ-GCS), and inhibited the cytochrome P4502E1 (CYP2E1) protein expression. Thus, the intervention mechanism of BAE on the AA-induced toxicity possibly attributed to the prevention of AA-induced oxidative stress and CYP2E1 activation. BAE would have potential application for the chemoprevention of the AA toxicity as a nutraceutical or a dietary supplement.

Protective Effects of CYP2E1 Inhibitors on Metabolic Syndrome-induced Liver Injury in Guinea Pigs

The present work reports the effects of CYP2E1-inhibitors (quercetin, 4methylpyrazole and disulfiram) on the indices characterizing state of the liver in guinea pigs with metabolic syndrome (MS) induced by protamine sulfate repeated administrations. The investigation of quercetin, 4-methylpyrazole and disulfiram effects on hepatic cytochrome P450 2E1 (CYP2E1) protein and activity changes was conducted. Simultaneously, the content of reactive oxygen species (ROS) and markers of liver damage were determined in experimental animals’ blood. The link between increased hepatic expression of CYP2E1, prominent ROS generation and liver damage in animals with MS has been discovered. It has been demonstrated that CYP2E1 protein content and activity in guinea pigs with MS rose almost 3 times compared to intact animals. These events were accompanied by increase in ROS generation and metabolism Original Research Article Rushchak et al.; BBJ, 7(2): 57-67, 2015; Article no.BBJ.2015.046 58 and liver disturbances symptoms: increase in serum glucose and cholesterol contents (2 and 2.6 times respectively), alanine aminotransferase (2.8 times), aspartate aminotransferase (6.4 times), and alkaline phosphatase (1.8 times) elevations. Our investigation suggests that administration of quercetin, 4-methylpyrazole, and disulfiram in guinea pigs with MS caused decrease in this isoenzyme protein expression (2.5, 1.7 and 2.4 respectively) as well as its enzymatic activity in liver (6.6, 1.1, and 1.7 respectively). The content of blood ROS was partially restored or normalized by all three CYP2E1 inhibitors. In turn, suppression of CYP2E1 activity and ROS generation led to decrease in hepatic MS manifestation. It is apparent from the present observation that quercetin has the highest efficiency among the investigated substances. Further studies on various quercetin doses and administration regimens could provide relevant information for the development of MSrelated nonalcoholic fatty liver disease treatment.

Isoliquiritigenin attenuates oxidative hepatic damage induced by carbon tetrachloride with or without buthionine sulfoximine

Glycyrrhizae radix (G. radix) has been demonstrated to have hepatoprotective properties. This study determined the therapeutic effects of isoliquiritigenin (isoLQ) in G. radix, against liver injury induced by CCl4 in rats. CCl4 (0.5ml/kg/d, twice) or CCl4 plus buthionine sulfoximine exerted severe liver damage assessed by increased plasma levels of alanine aminotransferase and aspartate aminotransferase, in addition to hepatic degeneration and necrosis. These pathological changes were markedly protected by pretreatment with isoLQ (5, 20mg/kg/d, p.o.) for 3 consecutive days. In addition, pretreatment with isoLQ inhibited CCl4-induced reduction of cytochrome P450 2E1 protein and mRNA expression as well as activity in the liver. Moreover, isoLQ pretreatment reversed the decrease in hepatic antioxidant capacity induced by CCl4 as well as suppressed expression of tumor necrosis factor-alpha and cyclooxigenase-2 in the liver. These results suggest that isoLQ has a protective effect against CCl4-induced liver damage through induction of antioxidant and anti-inflammatory activities.

Protective effects of maslinic acid against alcohol-induced acute liver injury in mice

Protective effects of maslinic acid (MA) at 10, 15 or 20 mg/kg body weight/day against alcohol-induced acute hepatotoxicity in mice were examined. Mice were administrated by MA for 3 weeks, and followed by alcohol treatment. Results showed that MA pre-intake at three doses resulted in its accumulation in the liver; and dose-dependently lowered cytochrome P450 2E1 activity and protein expression at 23.5–51.2% and 21.4–62.3%, respectively (P < 0.05). MA pre-intake decreased subsequent alcohol-induced reactive oxygen species, interleukin-6, tumor necrosis factor-alpha, monocyte chemoattractant protein-1, nitric oxide and prostaglandin E2 production; retained glutathione content; maintained catalase and glutathione peroxidase activities; and declined cyclooxygenase-2 and total nitric oxide synthase activities in the liver (P < 0.05). Furthermore, MA pre-intake suppressed 17.3–51.7% nuclear factor kappa (NF-κ)B p50, 23.5–58.8% NF-κB p65, 25.6–62.4% p-p38 and 24.1–63.0% p-JNK expression in the liver (P < 0.05). Histological data indicated that MA intake at test doses attenuated hepatic inflammatory infiltrate. These findings support that maslinic acid is a potent preventive agent against acute alcoholic liver disease.

Exposure to a northern contaminant mixture (NCM) alters hepatic energy and lipid metabolism exacerbating hepatic steatosis in obese JCR rats.

Non-alcoholic fatty liver disease (NAFLD), defined by the American Liver Society as the buildup of extra fat in liver cells that is not caused by alcohol, is the most common liver disease in North America. Obesity and type 2 diabetes are viewed as the major causes of NAFLD. Environmental contaminants have also been implicated in the development of NAFLD. Northern populations are exposed to a myriad of persistent organic pollutants including polychlorinated biphenyls, organochlorine pesticides, flame retardants, and toxic metals, while also affected by higher rates of obesity and alcohol abuse compared to the rest of Canada. In this study, we examined the impact of a mixture of 22 contaminants detected in Inuit blood on the development and progression of NAFLD in obese JCR rats with or without co-exposure to10% ethanol. Hepatosteatosis was found in obese rat liver, which was worsened by exposure to 10% ethanol. NCM treatment increased the number of macrovesicular lipid droplets, total lipid contents, portion of mono- and polyunsaturated fatty acids in the liver. This was complemented by an increase in hepatic total cholesterol and cholesterol ester levels which was associated with changes in the expression of genes and proteins involved in lipid metabolism and transport. In addition, NCM treatment increased cytochrome P450 2E1 protein expression and decreased ubiquinone pool, and mitochondrial ATP synthase subunit ATP5A and Complex IV activity. Despite the changes in mitochondrial physiology, hepatic ATP levels were maintained high in NCM-treated versus control rats. This was due to a decrease in ATP utilization and an increase in creatine kinase activity. Collectively, our results suggest that NCM treatment decreases hepatic cholesterol export, possibly also increases cholesterol uptake from circulation, and promotes lipid accumulation and alters ATP homeostasis which exacerbates the existing hepatic steatosis in genetically obese JCR rats with or without co-exposure to ethanol.

Emodin Ameliorates Ethanol-Induced Fatty Liver Injury in Mice

The liver plays a central role in ethanol (EtOH) metabolism, and oxidative stress is implicated in alcohol-mediated liver injury. The present study aimed to investigate the role of emodin in EtOH-induced fatty liver injury. Liver histology, biochemistry and gene-expression studies were performed. Mice fed with an EtOH-containing diet exhibited severe macrovesicular steatosis and higher serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. However, emodin ameliorated liver steatosis and lowered ALT and AST. Emodin also decreased hepatic triglyceride in mice fed with EtOH. In addition, emodin attenuates Oil Red O staining in alcoholic fatty liver in mice. Hepatic cytochrome P450 2E1 protein levels were upregulated in EtOH-fed mice, but downregulated in emodin-treated mice. In addition, emodin decreased hepatic oxidative stress. Furthermore, emodin significantly reduced liver α-smooth muscle actin and collagen type I, whereas it increased the mRNA levels of PPAR-γ. Taken together, emodin plays protective roles in alcohol-mediated liver steatosis.

The Effect of Aging on Acetaminophen Pharmacokinetics, Toxicity and Nrf2 in Fischer 344 Rats

We investigated the effect of aging on hepatic pharmacokinetics and the degree of hepatotoxicity following a toxic dose of acetaminophen. Young and old male Fischer 344 rats were treated with 800 mg/kg acetaminophen (young n = 8, old n = 5) or saline (young n = 9, old n = 9). Serum measurements showed old rats treated with acetaminophen had significantly lower serum alanine aminotransferase and higher acetaminophen and acetaminophen glucuronide levels and creatinine, compared with acetaminophen treated young rats (p < .05). Immunoblotting and activity assays showed old saline-treated rats had twofold lower cytochrome P450 2E1 activity and threefold higher NAD(P)H quinone oxireductase 1 protein expression and activity than young saline-treated rats (p < .05), although Nrf2, glutathione cysteine ligase-modulatory subunit, glutathione cysteine ligase-catalytic subunit, and cytochrome P450 2E1 protein expressions were unchanged. Primary hepatocytes isolated from young rats treated with 10 mM acetaminophen had lower survival than those from old rats (52.4% ± 5.8%, young; 83.6% ± 1.7%, old, p < .05). The pharmacokinetic changes described may decrease susceptibility to acetaminophen-induced hepatotoxicity but may increase risk of nephrotoxicity in old age.

CYP2E1 Testis Expression and Alcoholmediated Changes of Rat Spermatogenesis Indices and Type I Collagen

This study is a complex investigation of alcohol-mediated changes in CYP2E1 mRNA and protein expression in the testes, as well as spermatogenesis indices and type I collagen amino acid contents, in male rats. Wistar albino male rats were divided into two groups: I--control (intact animals), II--experimental (chronic alcoholism, exposure to a 15% ethanol aqueous solution during 150 days). The destructive changes in the spermatogenic epithelium were accompanied by a decrease in sperm number and motility time. CYP2E1 mRNA and protein expression were elevated in the testes 3 and 1.4 times, respectively. Also, significantly lower contents of lysine, glutamic acid, serine, proline, alanine, valine, and phenylalanine residues accompanied by an increase of hydroxyproline, glycine, and threonine residue contents were detected in the skin type I collagen of the experimental group. Chronic ethanol consumption caused testicular failure along with an overexpression of CYP2E1 mRNA and protein in the testes as well as quantitative changes in type I collagen amino acid contents. The profound alcohol-mediated changes in collagen type I amino acid contents may have affected the spermatogenic epithelium state. The modulation of testicular cytochrome P450 2E1 mRNA and protein expression could change the functioning of this isozyme in target organs and take part in the mechanism of ethanol gonadotoxicity.