Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04179 (MnSOD)
 2,777 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Although the mechanisms responsible for chemically induced oxidative stress are under intense investigation, little is known about the effects of prooxidant chemicals on the expression of drug-metabolizing enzymes. We examined the effects of diquat (0.1 mmol/kg, ip) and ciprofibrate (0.025% w/w, diet), chemicals which induce oxidative stress via different biochemical mechanisms, on the steady-state messenger RNA (mRNA) levels of six cytochrome P450 enzymes, seven glutathione S-transferase (GST) isoenzymes, UDP-glucuronosyl transferase 1-06 (UGT1*06), gamma-glutamylcysteine synthetase (gamma GCS), NADP(H):quinone oxidoreductase (quinone reductase), Cu/Zn superoxide dismutase (SOD), catalase, and 18S ribosomal RNA in the livers of male Sprague-Dawley rats. Effects of chemical treatments on mRNA levels were compared to changes in catalytic activities for selected enzymes. Ciprofibrate treatment selectively decreased CYP1A2 mRNA expression, whereas both chemicals suppressed CYP3A2 mRNA expression. CYP4A1 mRNA expression and lauric acid hydroxylase activities were induced by ciprofibrate treatment, whereas diquat treatment moderately increased CYP4A1 mRNA levels without affecting lauric acid hydroxylase activities. The steady-state mRNA levels encoding constitutively expressed GST isozymes (Ya1, Ya2, Yb1, Yb2, and Yc1) were decreased by diquat exposure, and the mRNA encoding four of the five constitutively expressed GSTs (Ya1, Ya2, Yb1, and Yc1) were also decreased by ciprofibrate treatment. Nonconstitutively expressed or low constitutively expressed genes (CYP1A1, CYP2B1, CYP2B2, GST Yc2, GST Yf, and UGT1*06) were not induced by exposure to the prooxidants. Changes in isozyme-specific catalytic activities were more consistent with the observed changes in mRNA expression for the GSTs than for the P450s. Both treatments had inhibitory effects on hepatic GSH biosynthesis by decreasing gamma GCS large-subunit mRNA expression, gamma GCS catalytic activities, and hepatic GSH concentrations. Cu/Zn SOD and quinone reductase mRNA levels were increased after ciprofibrate exposure, whereas Cu/Zn SOD mRNA expression was decreased in the diquat-treated animals. The results of this study indicate that diquat and ciprofibrate can decrease the expression profile of a number of phase I, phase II, and antioxidant enzymes and inhibit GSH biosynthesis. These effects may involve the pretranslational loss of hepatic mRNAs, possibly due to accelerated production of reactive oxygen species.
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PMID:The effects of diquat and ciprofibrate on mRNA expression and catalytic activities of hepatic xenobiotic metabolizing and antioxidant enzymes in rat liver. 767 60

Acetaminophen (APAP) hepatotoxicity remains the leading cause of drug-induced liver injury due to the lack of safe and effective therapeutic agents. Berberine (BBR) is a natural alkaloid derived from traditional medicine Rhizoma Coptidis and possesses various pharmacological properties. The aim of this study was to explore the hepatoprotective effects and underlying mechanisms of BBR on APAP-induced hepatotoxicity. Our results indicated that BBR pretreatment significantly ameliorated APAP-induced hepatic pathological abnormalities and attenuated the elevations of serum aminotransferases and liver/body weight ratio. Compared to APAP group, BBR notably increased the levels of hepatic UDP-glucuronosyltransferases and sulfotransferases, whereas failed to ameliorate APAP-induced GSH depletion. Pretreatment with BBR significantly reduced hepatic MDA and MPO levels, inhibited JNK phosphorylation and up-regulated the expression of nuclear Nrf-2 and its downstream gene Mn-SOD. Additionally, BBR obviously prevented APAP-induced DNA fragmentation. Furthermore, BBR pretreatment dramatically reduced the expression of pro-inflammatory cytokines, HMGB1, p-p65 and cleaved caspase-1 and inhibited the infiltration of macrophages and neutrophils. Taken these results together, BBR exhibits notable preventive effects on APAP-induced hepatotoxicity by inhibiting oxidative stress, hepatocyte necrosis and inflammatory response.
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PMID:Hepatoprotective effects of berberine on acetaminophen-induced hepatotoxicity in mice. 2986 14