OBJECTIVETo explore the effects of hydroquinone (HQ) on reactive oxygen species (ROS) generation, antioxydase activities and the expression of human 8-oxo-guanine DNA glycosylase (hOGG1) mRNA in human A549 lung adenocarcinoma cell strains.

METHODSA549 cells were treated with different concentrations of HQ. Cell survival was determined by methyl thiazolyl tetrazolium (MTT). Changes of ROS were detected by fluorescent probe. The contents of malonaldehyde and activities of antioxydase were determined through colorimetry. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to assess the level of hOGG1 mRNA.

RESULTSWith the increased concentration of HQ, the findings were as follows. (1) The absorbance value of A549 cell decreased. There was significant difference between 160 micromol/L (0.584+/-0.098) and 320 micromol/L (0.328+/-0.066) of HQ (q=5.56 and 9.07, P<0.05) with the control group (0.989+/-0.150), and the cell survival rate were less than 80%. (2) The ROS in A549 cell increased. 40 micromol/L (39.80+/-4.15) and 80 micromol/L (101.99+/-9.45) had statistical significance (q=10.74 and 30.32, P<0.05) with the control group (5.71+/-0.50). (3) It was found that the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) decreased and malonaldehyde (MDA) increased. Compared with the control group [(25.62+/-0.28) U/mg prot and (38.97+/-2.61) U/mg prot], the activities of SOD and GSH-Px had a significant decrease (q=12.17 and 8.78, P<0.05) in 80 micromol/L [(22.93+/-0.56) U/mg prot and (25.60+/-2.31) U/mg prot]. And MDA had a significant increase (q=10.90 and 15.49, P<0.05) in 40 micromol/L [(1.07+/-0.01) nmol/mg prot] and 80 micromol/L [(1.19+/-0.08) nmol/mg prot] as compared with the control group [(0.77+/-0.04) nmol/mg prot]. The decrease of SOD (r=-0.95, F=20.00, P=0.04) and GSH-Px activities (r=-0.99, F=115.48, P=0.01) and the increase of MDA contents (r=0.96, F=21.31, P=0.04) all had a dose-response relationship. (4) RT-PCR results showed that the expression of hOGG1 mRNA decreased. The significant difference was observed between the expression of hOGG1 mRNA in 80 micromol/L (0.478+/-0.017) (q=11.70, P<0.05) with the control group (0.715+/-0.038).

CONCLUSIONThis study suggests that HQ could induce oxidative damage and changes of the expression of hOGG1 mRNA in A549 cells.

Cell Line, Tumor ; DNA Glycosylases ; genetics ; Down-Regulation ; Gene Expression ; Gene Expression Regulation, Enzymologic ; drug effects ; Humans ; Hydroquinones ; toxicity ; RNA, Messenger ; genetics

Lead exposure is a known potential risk factor for neurodegenerative diseases such as Alzheimer's disease (AD). Exposure to lead during the critical phase of brain development has been linked with mental retardation and hypophrenia in later life. This study was aimed to investigate the effects of lead exposure of pregnant mice on the expressions of insulin-degrading enzyme (IDE) and nerve growth factor (NGF) in the hippocampus of their offspring. Blood samples were collected from the tail vein, and after anesthetizing the pups, the brain was excised on postnatal day 21. Lead concentrations were determined by graphite furnace atomic absorption spectrophotometry, and the expressions of IDE and NGF were determined by immunohistochemistry and Western blotting. Results showed that the reduction in IDE and NGF expression in the hippocampus of pups might be associated with impairment of learning and memory and dementia induced by maternal lead exposure during pregnancy and lactation.
Animals ; Down-Regulation ; Female ; Gene Expression Regulation, Developmental ; drug effects ; Gene Expression Regulation, Enzymologic ; drug effects ; Hippocampus ; drug effects ; growth & development ; metabolism ; Insulysin ; genetics ; metabolism ; Lead ; toxicity ; Mice ; Pregnancy ; Prenatal Exposure Delayed Effects ; chemically induced

To investigate the effect of sinomenine on lipopolysaccharide (LPS)-induced inflammation in RAW264.7 macrophages and the underlying mechanisms.
 Methods: The mouse RAW264.7 macrophages were treated with sinomenine and/or LPS with or without heme oxygenase-1 (HO-1) inhibitor Znpp. Real-time PCR, ELISA, immunofluenscence, and Western blot were used to detect the mRNA expression of TNF-α and IL-6, the release of TNF-α and IL-6, the protein expression of HO-1 and autophagy, respectively.
 Results: Compared with the control group, the mRNA expression and release of inflammatory cytokines TNF-α and IL-6 were increased, the green fluorescence of autophagy-related protein LC3 was accumulated and the protein expression of HO-1 was increased in RAW264.7 cells after LPS treatment (P<0.05). Compared with the LPS group, sinomenine treatment could reduce the mRNA expression and release of TNF-α and IL-6, accompanied by increasess in green fluorescence aggregation of LC3 and HO-1 production (P<0.05). HO-1 inhibitor Znpp could weaken the ability of sinomenine through suppressing TNF-α and IL-6 expression and decreasing the aggregation of LC3 green fluorescence (P<0.05).
 Conclusion: Sinomenine could alleviate LPS-induced inflammation in RAW264.7 macrophages, which might be related to HO-1 mediated autophagy. This study provides an experimental and theoretical basis for the clinical application of sinomenine in prevention and treatment of inflammation.
Animals ; Anti-Inflammatory Agents ; pharmacology ; Autophagy ; drug effects ; Gene Expression Regulation, Enzymologic ; drug effects ; Heme Oxygenase-1 ; genetics ; Inflammation ; chemically induced ; Lipopolysaccharides ; Macrophages ; drug effects ; Mice ; Morphinans ; pharmacology

BACKGROUNDA nonsteroidal anti-inflammatory drug, indomethacin, has been shown to have anti-leukemic activity and induce leukemic cell apoptosis. This study was to elucidate the mechanism of indomethacin-induced K562 cell apoptosis.

METHODSK562 cells were grown in RPMI 1640 medium and treated with different doses of indomethacin (0 micromol/L, 100 micromol/L, 200 micromol/L, 400 micromol/L, 800 micromol/L) for 72 hours. The cells were harvested, and cell viability or apoptosis was analyzed using MTT assay and AO/EB stain, combining laser scanning confocal microscopy (LSCM) technique separately. For the localization and distribution of intracellular caspase-3 or caspase-8 protein, immunofluorescence assay was carried out. To reveal the activation of caspase-3 or caspase-8 in indomethacin-treated cells, Western blot detection was used. The change in intracellular free calcium was determined by Fluo-3/Am probe labeling combined with LSCM.

RESULTSIndomethacin could lead to K562 cell apoptosis and inhibit cell viability in a concentration-dependent manner. An increased expression of intracellular caspase-3 or caspase-8 was observed at higher doses of indomethacin (400 - 800 micromol/L). Western blot results showed upregulation and activation in both caspase-3 and caspase-8 protein. Under indomethacin intervention, the levels of intracellular free calcium showed a significant increase. Blocking the activity of cyclooxygenase did not abolish the effects of indomethacin on K562 cell apoptosis.

CONCLUSIONSActivation and upregulation of caspase-3 or caspase-8 protein were responsible for Indomethacin-induced K562 cell apoptosis. Variation of intracellular free calcium might switch on the apoptotic pathway and the proapoptotic effect of indomethacin might be cyclooxygenase-independent.

Apoptosis ; drug effects ; Calcium ; metabolism ; Caspase 3 ; Caspase 8 ; Caspases ; genetics ; metabolism ; Cyclooxygenase Inhibitors ; pharmacology ; Enzyme Activation ; Gene Expression Regulation, Enzymologic ; drug effects ; Humans ; Indomethacin ; pharmacology ; K562 Cells

Animals ; Anticarcinogenic Agents ; pharmacology ; Cytochrome P-450 Enzyme System ; drug effects ; genetics ; metabolism ; Food-Drug Interactions ; Gene Expression Regulation, Enzymologic ; Herb-Drug Interactions ; Humans ; Plant Preparations ; pharmacology

OBJECTIVETo establish an in vitro heterogeneous expression model of human CYP2E1 (hCYP2E1) cDNA and investigate the effect of the chemical carcinogenic N, N'-dinitrosopiperazine (DNP) on the expression of CYP2E1.

METHODSExogenous hCYP2E1 was introduced into the mouse derived NIH3T3 cells using the lipofectamine transfection technique. Integration of exogenous hCYP2E1 gene was identified by PCR and Southern blot. After treatment with various concentration of ethanol and DNP on the transfected NIH3T3 cell cultures, RT-PCR and Western blot was applied to detect the expression level of CYP2E1.

RESULTSTwo cell clones with integration and stable expression of exogenous hCYP2E1 were obtained and designated as NIH3T3-2E1-A4 and NIH3T3-2E1-A8 respectively. The expression of both hCYP2E1 mRNA and protein products was promoted after either ethanol or DNP treatment.

CONCLUSIONThe results suggested that the promoted expression of hCYP2E1 induced by DNP and /or ethanol is due to enhanced transcription. The mechanism of DNP carcinogenes is might be related to this in situ activated metabolism by CYP2E1.

3T3 Cells ; Animals ; Carcinogens ; toxicity ; Cytochrome P-450 CYP2E1 ; genetics ; Ethanol ; pharmacology ; Gene Expression Regulation, Enzymologic ; drug effects ; Humans ; Mice ; Nitrosamines ; toxicity ; Reverse Transcriptase Polymerase Chain Reaction ; Transfection

To investigate the effects of genistein (Gen) on the biosynthesis of N-glycolylneuraminic acid (Neu5Gc) in rats, 80 4-week-old male SD rats were randomly equally into the control and genistein groups. The rats of control and genistein groups were fed 5% ethanol and 300 mg/(kg·d) genistein respectively by gavage. The contents of Neu5Gc in hind leg muscle, kidney and liver tissues of rats were measured by using high performance liquid chromatography coupled with fluorescence detector (HPLC/FLD), and the mechanism of inhibition of Neu5Gc synthesis was investigated by using the molecular docking of Gen and sialyltransferase. On the 15th day, the content of Neu5Gc in hind leg muscle and liver tissues decreased 13.77% and 15.45%, respectively, and there was no significant change in the content of Neu5Gc in kidney tissues. On the 30th day, the content of Neu5Gc in liver tissues decreased 13.35%, however, there was no significant change in the content of Neu5Gc in kidney tissues and Neu5Gc was not detected in hind leg muscle. The content of Neu5Gc in hind leg muscle, kidney and liver tissues decreased respectively 32.65%, 32.78%, 16.80% and 12.72%, 11.42%, 12.30% while rats fed on the 45th and the 60th days. Genistein has formed the hydrogen bond with sialyltransferase activity site residues His319, Ser151, Gly293, Thr328 and formed a hydrophobic interactions with the residues His302, His301, Trp300, Ser271, Phe292, Thr328, Ser325 and Ile274. The results of molecular docking indicated that the weak intermolecular interaction was the main cause of genistein inhibiting sialyltransferase activity. The research results provided an experimental basis for the subsequent reduction of Neu5Gc in red meat before slaughter.
Animals ; Gene Expression Regulation, Enzymologic ; drug effects ; Genistein ; pharmacology ; Male ; Molecular Docking Simulation ; Neuraminic Acids ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Transferases ; metabolism

Antioxidants ; metabolism ; Benzoxepins ; pharmacology ; Cell Line ; Gene Expression Regulation, Enzymologic ; drug effects ; Humans ; Limonins ; pharmacology ; NF-E2-Related Factor 2 ; metabolism ; Oxidoreductases ; biosynthesis

Fifty male Wistar rats were fed a standard chow diet or a high-fat (HF) diet, and different concentrations of green tea polyphenols (GTPs) (0.8, 1.6, and 3.2 g/L) were administered in the drinking water. We found that the malondialdehyde (MDA) level in the HF diet group was significantly higher than that in the control (CON) group (P<0.05). Decreased peroxisome proliferator-activated receptor (PPAR)-α and sirtuin 3 (SIRT3) expression, and increased manganese superoxide dismutase (MnSOD) acetylation levels were also detected in the HF diet group (P<0.05). GTP treatment upregulated SIRT3 and PPARα expression, increased the pparα mRNA level, reduced the MnSOD acetylation level, and decreased MDA production in rats fed a HF diet (P<0.05). No significant differences in total renal MnSOD and PPAR-γ coactivator-1α (PGC1-α) expression were detected. The reduced oxidative stress detected in kidney tissues after GTP treatment was partly due to the higher SIRT3 expression, which was likely mediated by PPARα.
Acetylation ; drug effects ; Animals ; Antioxidants ; pharmacology ; Diet, High-Fat ; adverse effects ; Gene Expression Regulation, Enzymologic ; drug effects ; Kidney ; drug effects ; metabolism ; Male ; Oxidative Stress ; drug effects ; Polyphenols ; pharmacology ; Rats ; Rats, Wistar ; Reactive Oxygen Species ; metabolism ; Sirtuin 3 ; metabolism ; Tea ; chemistry

OBJECTIVETo investigate the effects of insulin-like growth factor II (IGF-II) on promoting cell proliferation, regulating levels of cellular nitric oxide (NO) and mRNA transcriptions of inducible nitric oxide synthase (iNOS) and endothelial NOS (eNOS) in mouse osteoblast-like cells.

METHODSMouse osteoblastic cell line MC3T3-E1 was selected as the effective cell of IGF-II. After the cells were treated with IGF-II at different concentrations for different time duration, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) colorimetric assay was used to examine cell proliferation, and nitrate reductase method was applied to detect NO concentrations in cell culture supernatants and quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) was employed to determine transcription levels of cellular iNOS and eNOS mRNAs.

RESULTSAfter the MC3T3-E1 cells were treated with IGF-II at concentration of 1 ng/ml for 72 h, 10 and 100 ng/ml for 24, 48 and 72 h respectively, all the MTT values increased (P<0.05 or P<0.01) with obvious dosage-time dependent pattern. NO levels of the MC3T3-E1 cells treated with 100 ng/ml IGF-II for 48 h, and with 1, 10 and 100 ng/ml IGF-II for 72 h were remarkably lower than that of the normal control, respectively (P<0.05 or P<0.01). After the cells were treated with 100 ng/ml IGF-II for 48 h cellular iNOS mRNA levels were significantly decreased (P<0.01). But the levels of eNOS mRNA in the cells treated with each of the used IGF-II dosages for different time duration did not show any differences compared with the normal control (P>0.05).

CONCLUSIONIGF-II at different concentrations could promote proliferation of mouse MC3T3-E1 cell. This cell proliferation promotion was associated with the low NO levels maintained by IGF-II. Higher concentration of IGF-II could down-regulate iNOS gene expression at the level of transcription but not affect transcription of eNOS mRNA, which might be one of the mechanisms for IGF-II maintenance of the low NO levels in MC3T3-E1 cells.

3T3 Cells ; Animals ; Cell Proliferation ; drug effects ; Dose-Response Relationship, Drug ; Gene Expression Regulation, Enzymologic ; drug effects ; physiology ; Insulin-Like Growth Factor II ; administration & dosage ; Mice ; Osteoblasts ; cytology ; drug effects ; physiology