The present study investigated the mechanism of the Tibetan medicine Ershiwuwei Songshi Pills(ESP) against the liver injury induced by acetaminophen(APAP) in mice based on the kelch-like ECH-associated protein 1(Keap1)/nuclear transcription factor E2 related factor 2(Nrf2) and Toll-like receptor 4(TLR4)/nuclear factor-kappa B(NF-κB) p65 signaling pathways. Kunming mice were randomly divided into a blank control group, a model group, an N-acetyl-L-cysteine(NAC) group, and high-(400 mg·kg~(-1)), medium-(200 mg·kg~(-1)), and low-dose(100 mg·kg~(-1)) ESP groups. After 14 days of continuous administration, except for those in the control group, the mice were intraperitoneally injected with 200 mg·kg~(-1) APAP. After 12 h, the serum and liver tissues of mice were collected. Hematoxylin-eosin(HE) staining was performed on pathological sections of the liver, and the levels of aspartate aminotransferase(AST) and alanine aminotransferase(ALT) in the serum and the levels of glutathione(GSH), malondialdehyde(MDA), superoxide dismutase(SOD), catalase(CAT), myeloperoxidase(MPO), and total antioxidant capacity(T-AOC) in liver tissue homogenate were detected to observe and analyze the protective effect of ESP on APAP-induced liver injury in mice. The serum levels of tumor necrosis factor-alpha(TNF-α), interleukin-1 beta(IL-1β), and interleukin-6(IL-6) were determined by enzyme-linked immunosorbent assay(ELISA). The protein expression of Nrf2, Keap1, TLR4, and NF-κB p65 in the liver was determined by Western blot. Quantitative real-time was used to determine the mRNA expression of glutamate-cysteine ligase catalytic subunit(GCLC), glutamate-cysteine ligase regulatory subunit(GCLM), heme oxygenase-1(HO-1), and NAD(P)H dehydrogenase quinone 1(NQO-1) in the liver to explore the mechanism of ESP in improving APAP-induced liver damage in mice. As revealed by results, compared with the model group, the ESP groups showed improved liver pathological damage, decreased ALT and AST levels in the serum and MDA and MPO content in the liver, increased GSH, SOD, CAT, and T-AOC in the liver, reduced TNF-α and IL-6 levels in the serum, down-regulated expression of Keap1 in the liver cytoplasm and NF-κB p65 in the liver nucleus, up-regulated expression of Nrf2 in the liver nucleus, insignificant change in TLR4 expression, and elevated relative mRNA expression levels of antioxidant genes GCLC, GCLM, HO-1, and NQO-1. ESP can reduce the oxidative damage and inflammation caused by APAP, and the mechanism may be related to the Keap1/Nrf2 signaling pathway and the signal transduction factors on the TLR4/NF-κB p65 pathway.
Acetaminophen/toxicity* ; Animals ; Antioxidants/pharmacology* ; Glutamate-Cysteine Ligase/pharmacology* ; Glutathione ; Interleukin-6/metabolism* ; Kelch-Like ECH-Associated Protein 1/metabolism* ; Liver ; Medicine, Tibetan Traditional ; Mice ; NF-E2-Related Factor 2/metabolism* ; NF-kappa B/metabolism* ; RNA, Messenger/metabolism* ; Signal Transduction ; Superoxide Dismutase/metabolism* ; Toll-Like Receptor 4/metabolism* ; Tumor Necrosis Factor-alpha/metabolism*

Due to the critical location and physiological activities of the retinal pigment epithelial (RPE) cell, it is constantly subjected to contact with various infectious agents and inflammatory mediators. However, little is known about the signaling events in RPE involved in Toxoplasma gondii infection and development. The aim of the study is to screen the host mRNA transcriptional change of 3 inflammation-related gene categories, PI3K/Akt pathway regulatory components, blood vessel development factors and ROS regulators, to prove that PI3K/Akt or mTOR signaling pathway play an essential role in regulating the selected inflammation-related genes. The selected genes include PH domain and leucine- rich-repeat protein phosphatases (PHLPP), casein kinase2 (CK2), vascular endothelial growth factor (VEGF), pigment epithelium-derived factor (PEDF), glutamate-cysteine ligase (GCL), glutathione S-transferase (GST), and NAD(P)H: quinone oxidoreductase (NQO1). Using reverse transcription polymerase chain reaction (RT-PCR) and quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR), we found that T. gondii up-regulates PHLPP2, CK2β, VEGF, GCL, GST, and NQO1 gene expression levels, but down-regulates PHLPP1 and PEDF mRNA transcription levels. PI3K inhibition and mTOR inhibition by specific inhibitors showed that most of these host gene expression patterns were due to activation of PI3K/Akt or mTOR pathways with some exceptional cases. Taken together, our results reveal a new molecular mechanism of these gene expression change dependent on PI3K/Akt or mTOR pathways and highlight more systematical insight of how an intracellular T. gondii can manipulate host genes to avoid host defense.
Blood Vessels ; Caseins ; Epithelial Cells ; Gene Expression ; Glutamate-Cysteine Ligase ; Glutathione Transferase ; Hydrogen-Ion Concentration ; Phosphoprotein Phosphatases ; Polymerase Chain Reaction ; Reactive Oxygen Species ; Retinaldehyde ; Reverse Transcription ; RNA, Messenger ; Signal Transduction ; Toxoplasma ; Toxoplasmosis ; Vascular Endothelial Growth Factor A

BACKGROUND/OBJECTIVES: The honeysuckle berry (HB) contains ascorbic acid and phenolic components, especially anthocyanins, flavonoids, and low-molecular-weight phenolic acids. In order to examine the potential of HB as a hepatoprotective medicinal food, we evaluated the in vitro anti-oxidant and anti-inflammatory activities of Korean HB (HBK) and Chinese HB (HBC). MATERIALS/METHODS: Antioxidant and anti-inflammatory effects of the extracts were examined in HepG2 and RAW 264.7 cells, respectively. The anti-oxidant capacity was determined by DPPH, SOD, CAT, and ARE luciferase activities. The production of nitric oxide (NO) as an inflammatory marker was also evaluated. The Nrf2-mediated mRNA levels of heme oxygenase-1 (HO-1), NAD(P)H dehydrogenase [quinone] 1 (Nqo1), and glutamate-cysteine ligase catalytic subunit (Gclc) were measured. The concentrations of HB extracts used were 3, 10, 30, 100, and 300 µg/mL. RESULTS: The radical scavenging activity of all HB extracts increased in a concentration-dependent manner (P < 0.01 or P < 0.05). SOD (P < 0.05) and CAT (P < 0.01) activities were increased by treatment with 300 µg/mL of each HB extract, when compared to those in the control. NO production was observed in cells pretreated with 100 or 300 µg/mL of HBC and HBK (P < 0.01). Treatment with 300 µg/mL of HBC significantly increased Nqo1 (P < 0.01) and Gclc (P < 0.05) mRNA levels compared to those in the control. Treatment with 300 µg/mL of HBK (P < 0.05) and HBC (P < 0.01) also significantly increased the HO-1 mRNA level compared to that in the control. CONCLUSIONS: Thus, the Korean and Chinese HBs were found to possess favorable in vitro anti-oxidant and anti-inflammatory activities. Nrf2 and its related anti-oxidant genes were associated with both anti-oxidant and anti-inflammatory activities in HB-treated cells. Further studies are needed to confirm these in vivo effects.
Animals ; Anthocyanins ; Ascorbic Acid ; Asian Continental Ancestry Group* ; Catalytic Domain ; Cats ; Flavonoids ; Fruit ; Glutamate-Cysteine Ligase ; Heme Oxygenase-1 ; Humans ; In Vitro Techniques* ; Lonicera* ; Luciferases ; Nitric Oxide ; Oxidoreductases ; Phenol ; RAW 264.7 Cells ; RNA, Messenger

Previously, we demonstrated that galangin (3,5,7-trihydroxyflavone) protects human keratinocytes against ultraviolet B (UVB)-induced oxidative damage. In this study, we investigated the effect of galangin on induction of antioxidant enzymes involved in synthesis of reduced glutathione (GSH), and investigated the associated upstream signaling cascades. By activating nuclear factor-erythroid 2-related factor (Nrf2), galangin treatment significantly increased expression of glutamate-cysteine ligase catalytic subunit (GCLC) and glutathione synthetase (GSS). This activation of Nrf2 depended on extracellular signal-regulated kinases (ERKs) and protein kinase B (AKT) signaling. Inhibition of GSH in galangin-treated cells attenuated the protective effect of galangin against the deleterious effects of UVB. Our results reveal that galangin protects human keratinocytes by activating ERK/AKT-Nrf2, leading to elevated expression of GSH-synthesizing enzymes.
Catalytic Domain ; Extracellular Signal-Regulated MAP Kinases ; Glutamate-Cysteine Ligase ; Glutathione Synthase ; Glutathione* ; Humans* ; Keratinocytes* ; Proto-Oncogene Proteins c-akt

BACKGROUND: Exposure to ethanol abuse and severe oxidative stress are risk factors for hepatocarcinoma. The aim of this study was to evaluate the effects of S-adenosylmethionine (SAMe) and its combinations with taurine and/or betaine on the level of glutathione (GSH), a powerful antioxidant in the liver, in acute hepatotoxicity induced by ethanol. METHODS: To examine the effects of SAMe and its combinations with taurine and/or betaine on ethanol-induced hepatotoxicity, AML12 cells and C57BL/6 mice were pretreated with SAMe, taurine, and/or betaine, followed by ethanol challenge. Cell viability was detected with an MTT assay. GSH concentration and mRNA levels of GSH synthetic enzymes were measured using GSH reductase and quantitative real-time reverse transcriptase-PCR. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were measured with commercially available kits. RESULTS: Pretreatment of SAMe, with or without taurine and/or betaine, attenuated decreases in GSH levels and mRNA expression of the catalytic subunit of glutamate-cysteine ligase (GCL), the rate-limiting enzyme for GSH synthesis, in ethanol-treated cells and mice. mRNA levels of the modifier subunit of GCL and glutathione synthetase were increased in mice treated with SAMe combinations. SAMe, taurine, and/or betaine pretreatment restored serum ALT and AST levels to control levels in the ethanol-treated group. CONCLUSIONS: Combinations of SAMe with taurine and/or betaine have a hepatoprotective effect against ethanol-induced liver injury by maintaining GSH homeostasis.
Alanine Transaminase ; Animals ; Aspartate Aminotransferases ; Betaine* ; Catalytic Domain ; Cell Survival ; Ethanol ; Glutamate-Cysteine Ligase ; Glutathione Synthase ; Glutathione* ; Homeostasis* ; Liver ; Mice ; Oxidative Stress ; Oxidoreductases ; Risk Factors ; RNA, Messenger ; S-Adenosylmethionine* ; Taurine*

Aims: Glutamate cysteine ligase (GCL) enzyme is involved in the synthesis of glutathione, which functions as an antioxidant. Polymorphisms in the sequence of amino acids making up the gene GCLC will cause differences in enzyme expression and GCLC activity. Gene expression that is influenced by oxidative stress can be used to measure markers such as F2-isoprostanes. This study aims to examine the association between the polymorphism in the GCLC gene with glutathione plasma level and F2-isoprostanes in contacts of person with infectious tuberculosis (TB). Methodology and results: Samples are taken from the family members of pulmonary TB patients who seeks treatment at the Pulmonary Centre (Lung Health Center for Public = BBKPM) and Policlinic of Dr Wahidin Sudirohusodo Hospital, Makassar. Total of approximately 4 mL of venous blood are taken from each person with pulmonary TB contacts and furtherly analyzed using genomic PCR-RFLP method and ELISA. Our results described that contacts of person with infectious TB for approximately 6 months have polymorphism C/C genotype at 80.3%, C/T of 18.3% and T/T for 1.4% of the total 71 samples with high levels of glutathione from 0.167 to 0.548 mM/mL and F2-isoprostanes level 72.4 - 1343.9 pg/mL. Conclusion, significance and impact of study: There are no significant association between GCLC gene polymorphism with glutathione and F2-isoprostanes levels of individual who had contacted infection TB. In this study the elevation of F2-isoprostanes equal to the decrease levels of glutathione.
Glutamate-Cysteine Ligase

BACKGROUND/OBJECTIVES: This study investigated the antioxidant activities and hepatoprotective effects of Schisandra chinensis Baillon extract (SCE) against tert-butyl hydroperoxide (t-BHP)-induced oxidative hepatic damage in rats. MATERIALS/METHODS: Sprague-Dawley (SD) rats were pretreated with SCE (300, 600, and 1,200 mg/kg BW) or saline once daily for 14 consecutive days. On day 14, each animal, except those belonging to the normal control group, were injected with t-BHP (0.8 mmol/kg BW/i.p.), and all of the rats were sacrificed 16 h after t-BHP injection. RESULTS: Although no significant differences in AST and ALT levels were observed among the TC and SCE groups, the high-dose SCE group showed a decreasing tendency compared to the TC group. However, erythrocyte SOD activity showed a significant increase in the low-dose SCE group compared with the TC group. On the other hand, no significant differences in hepatic total glutathione (GSH) level, glutathione reductase (GR), and glutathione peroxidase (GSH-Px) activities were observed among the TC and SCE groups. Hepatic histopathological evaluation revealed that pretreatment with SCE resulted in reduced t-BHP-induced incidence of lesions, such as neutrophil infiltration, swelling of liver cells, and necrosis. In particular, treatment with a high dose of SCE resulted in induction of phase II antioxidant/detoxifying enzyme expression, such as glutathione S-transferase (GST) and glutamate-cysteine ligase catalytic subunit (GCLC). CONCLUSIONS: Based on these results, we conclude that SCE exerts protective effects against t-BHP induced oxidative hepatic damage through the reduction of neutrophil infiltration, swelling of liver cells, and necrosis. In addition, SCE regulates the gene expression of phase II antioxidant/detoxifying enzymes independent of hepatic antioxidant enzyme activity.
Animals ; Catalytic Domain ; Erythrocytes ; Gene Expression* ; Glutamate-Cysteine Ligase ; Glutathione ; Glutathione Peroxidase ; Glutathione Reductase ; Glutathione Transferase ; Hand ; Incidence ; Liver ; Necrosis ; Neutrophil Infiltration ; Rats* ; Rats, Sprague-Dawley ; Schisandra* ; tert-Butylhydroperoxide

OBJECTIVE: To investigate the protective effect of celastrol on allergic rhinitis rats and its possible mechanism. METHOD: Allergic rhinitis (AR) model of rats was established by OVA. The behavioural characteris tics were observed at the 1st, 4th and 7th dayafter stimulation treatment. The levels of superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH) and glutathione peroxidase (GSH-PX) in the nasal mucosa breathing zone were measured. The expression of the nuclear factor erythroid 2 related factor 2 (NRF2) nuclear protein and the catalytic submit of glutamylcysteine ligase (GCLC) cytoplasmic protein in the nasal mucosa breath ing zone were determined. RESULT: We observed obvious behaviour changes related with allergic rhinitis in AR rats, together with decrease of SOD, GSH and GSH-PX and increase of MDA in the nasal mucosa breathing zone. Moreover, NRF2 nuclear protein expression and GCLC cytoplasmic expression were suppressed in the nasal mucosa. The changes above were alleviated in celastrol pretreatment group. The potential mechanism may be related to the upregulation of NRF2 nuclear protein expression and GCLC cytoplasmic expression after celastrol pretreatment. CONCLUSION Celastrol can significantly relieve the allergic symptoms in AR rats. The mechanism of this protective effects may relate to the upregulation of NRF2 nuclear protein expression and GCLC cytoplasmic expression in the nasal mucosa breathing zone.
Animals ; Disease Models, Animal ; Glutamate-Cysteine Ligase ; metabolism ; Male ; NF-E2-Related Factor 2 ; metabolism ; Nasal Mucosa ; metabolism ; Rats ; Rats, Sprague-Dawley ; Rhinitis, Allergic ; drug therapy ; Triterpenes ; therapeutic use

OBJECTIVETo investigate the protective effects of docosahexaenoic acid (DHA) and nervonic acid (NA) on the learning and memory abilities in rats exposed to 1-bromopropane (1-BP) and their action mechanisms.

METHODSForty male Wistar rats (specific pathogen-free) were randomly divided into 4 groups (n = 10 for each), i.e., solvent control group, 1-BP (800 mg/kg) group, NA (150 mg/kg) + 1-BP (800 mg/kg) group, and DHA (500 mg/kg) + 1-BP (800 mg/kg) group. The rats were given respective test substances by gavage for 7 d. The Morris water maze (MWM) test was performed from days 8 to 12 to evaluate the rats' learning and memory abilities. After MWM test, rats were sacrificed in the next day, and cerebral cortex was quickly dissected and homogenized in an ice bath. The supernatant of the obtained homogenate was collected to measure the content of glutathione (GSH) and malondialdehyde (MDA) and the activities of glutathione reductase (GR) and γ-glutamate cysteine ligase (γ-GCL).

RESULTSThe MWM spatial navigation test showed that the 1-BP group had significantly longer escape latency and significantly longer total swimming distance compared with the control group (P<0.05), while the DHA+1-BP group had significant decreases in escape latency and total swimming distance compared with the 1-BP group (P<0.05). The spatial probe test showed that the number of platform crossings was significantly greater in the DHA+1-BP group and NA+1-BP group than in the 1-BP group (P<0.05); compared with the control group, the 1-BP group had a significantly lower ratio of time spent in the zone around the platform to total time (P < 0.05), and the ratio was significantly higher in the DHA+1-BP group than in the 1-BP group (P < 0.05). Compared with the control group, the 1-BP group had a 18.1% decrease in GSH content, and DHA could significantly reverse 1-BP-induced decrease in GSH content (P < 0.05). Compared with the 1-BP group, the DHA+1-BP group and NA+1-BP group had significantly decreased MDA content (P < 0.05), the DHA+1-BP group had significantly increased GR activity (P < 0.05), and the NA+1-BP group had significantly increased γ-GCL activity (P < 0.05).

CONCLUSIONThe rats exposed to 1-BP have oxidative stress in the brain and impaired cognitive function. DHA and NA can reduce 1-BP-induced cognitive function impairment in rats, possibly by increasing the activities of GR and γ-GCL and the content of GSH in the brain.

Animals ; Behavior, Animal ; Brain ; drug effects ; Docosahexaenoic Acids ; pharmacology ; Fatty Acids, Monounsaturated ; pharmacology ; Glutamate-Cysteine Ligase ; metabolism ; Glutathione ; metabolism ; Glutathione Reductase ; metabolism ; Hydrocarbons, Brominated ; toxicity ; Male ; Malondialdehyde ; metabolism ; Maze Learning ; drug effects ; Memory ; drug effects ; Oxidative Stress ; Rats ; Rats, Wistar

The aim of this study is to investigate the protection effect of tanshinone IIA (Tan) against triptolide (TP)-induced liver injury and the mechanisms involved. Acute liver injury was induced by intraperitoneal injection of TP (1 mg x kg(-1)) in mice. The activities of AST, ALT and LDH in serum and the levels of GSH, GST, GSH-PX, SOD, CAT and MDA in liver tissue were detected. The histopathological changes of liver tissues were observed after HE staining. Nrf2 translocation in liver tissue was detected by Western blotting, and real-time PCR was used to measure the expression levels of GCLC, NQO1 and HO-1 mRNA. The results showed that pretreatment with Tan significantly prevented the TP induced liver injury as indicated by reducing the activities of AST, ALT and LDH (P < 0.01). Tan pretreatment also prevented TP-induced oxidative stress in the mice liver by inhibiting MDA and restoring the levels of GSH, GST, SOD and CAT (P < 0.05). Parallel to these changes, pretreatment with Tan could attenuate histopathologic changes induced by TP. Furthermore, the results indicated that Tan pretreatment caused nuclear accumulation of Nrf2 as well as induction of mRNA expression of antioxidant response element (ARE)-driven genes such as GCLC, NQO1 and HO-1. These results indicated that Tan could protect against TP-induced acute liver injury via the activation of Nrf2/ARE pathway.
Animals ; Antioxidant Response Elements ; drug effects ; Chemical and Drug Induced Liver Injury ; metabolism ; pathology ; Diterpenes ; toxicity ; Diterpenes, Abietane ; pharmacology ; Drugs, Chinese Herbal ; pharmacology ; Epoxy Compounds ; toxicity ; Glutamate-Cysteine Ligase ; genetics ; metabolism ; Heme Oxygenase-1 ; genetics ; metabolism ; Liver ; metabolism ; pathology ; Male ; Membrane Proteins ; genetics ; metabolism ; Mice ; Mice, Inbred C57BL ; NAD(P)H Dehydrogenase (Quinone) ; genetics ; metabolism ; NF-E2-Related Factor 2 ; metabolism ; Phenanthrenes ; toxicity ; RNA, Messenger ; metabolism ; Signal Transduction ; drug effects