OBJECTIVETo investigate the role of NADPH oxidase (Nox) in the oxidative stress injury of human dermal fibroblasts (HFbs).

METHODSAn oxidative stress injury model was established in HFbs by exposure to H(2)O(2). Normal HFbs and HFbs exposed to H(2)O(2) with and without pretreatment with NADPH oxidase inhibitor were tested for cell viability using MTT assay, and the intracellular reactive oxygen species (ROS) were determined with a DCFH-DA fluorescent probe. Western blotting was used to measure the protein expressions of membrane-bound subunit gp91phox of NADPH oxidase in the cells.

RESULTH(2)O(2) time- and concentration-dependently induced oxidative stress injury in the fibroblasts, causing a reduction of the cell viability to 40% after a 24-h exposure at 700 µmol/L (P<0.05) and an increase of ROS by 2 folds after a 2-h exposure at 700 µmol/L (P<0.05). Compared with the cells with oxidative stress injury, the cells with NADPH oxidase inhibitor pretreatment showed a 20% higher cell viability (P<0.05) and normal ROS level (P<0.05) following H(2)O(2) exposure. Western blotting demonstrated increased expression of gp91phox in the cells exposed to increasing H(2)O(2) concentrations, but gp91phox expression remained normal in cells pretreated with NADPH oxidase inhibitor.

CONCLUSIONH(2)O(2) can induce oxidative stress injury in the fibroblasts by affecting NADPH oxidase, especially its membrane-bound subunit gp91phox.

Cell Survival ; Cells, Cultured ; Fibroblasts ; cytology ; enzymology ; Humans ; Hydrogen Peroxide ; Membrane Glycoproteins ; metabolism ; NADPH Oxidase 2 ; NADPH Oxidases ; antagonists & inhibitors ; metabolism ; Oxidation-Reduction ; Oxidative Stress ; Reactive Oxygen Species ; metabolism

The aim of the present study is to investigate how cytochrome P450 enzymes (CYP) 2C8-derived epoxyeicosatrienoic acids (EETs) regulate the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway and protect against oxidative stress-induced endothelial injuries in the development and progression of atherosclerosis. In this study, cultured human umbilical vein endothelial cells (HUVECs) were transfected with CYP2C8 or pretreated with exogenous EETs (1 μmol/L) before TNF-α (20 ng/mL) stimulation. Apoptosis and intracellular ROS production were determined by flow cytometry. The expression levels of ROS-associated NAD(P)H subunits gp91 and p47, the anti-oxidative enzyme catalase (CAT), Nrf2, heme oxygenase-1 (HO-1) and endothelial nitric oxide synthase (eNOS) were detected by Western blotting. The results showed that CYP2C8-derived EETs decreased apoptosis of HUVECs treated with TNF-α. Pretreatment with 11, 12-EET also significantly blocked TNF-α-induced ROS production. In addition, 11, 12-EET decreased oxidative stress-induced apoptosis. Furthermore, the ability of 11, 12-EET to protect cells against TNF-α-induced apoptosis via oxidative stress was abrogated by transient transfection with Nrf2-specific small interfering RNA (siRNA). In conclusion, CYP2C8-derived EETs prevented TNF-α-induced HUVECs apoptosis via inhibition of oxidative stress associated with the Nrf2 signaling.
8,11,14-Eicosatrienoic Acid ; analogs & derivatives ; metabolism ; pharmacology ; Adaptor Proteins, Signal Transducing ; genetics ; metabolism ; Apoptosis ; drug effects ; Aryl Hydrocarbon Hydroxylases ; genetics ; metabolism ; Atherosclerosis ; genetics ; metabolism ; pathology ; Catalase ; genetics ; metabolism ; Cytochrome P-450 CYP2C8 ; genetics ; metabolism ; Gene Expression Regulation ; Heme Oxygenase-1 ; genetics ; metabolism ; Human Umbilical Vein Endothelial Cells ; cytology ; drug effects ; metabolism ; Humans ; Membrane Glycoproteins ; genetics ; metabolism ; Models, Biological ; NADPH Oxidase 2 ; NADPH Oxidases ; genetics ; metabolism ; NF-E2-Related Factor 2 ; antagonists & inhibitors ; genetics ; metabolism ; Nitric Oxide Synthase Type III ; genetics ; metabolism ; RNA, Small Interfering ; genetics ; metabolism ; Reactive Oxygen Species ; antagonists & inhibitors ; metabolism ; Signal Transduction ; Tumor Necrosis Factor-alpha ; metabolism ; pharmacology

OBJECTIVEThe roles of cerebrovascular oxidative stress in vascular functional remodeling have been described in hindlimb-unweighting (HU) rats. However, the underlying mechanism remains to be established.

METHODSWe investigated the generation of vascular reactive oxygen species (ROS), Nox2/Nox4 protein and mRNA levels, NADPH oxidase activity, and manganese superoxide dismutase (MnSOD) and glutathione peroxidase-1 (GPx-1) mRNA levels in cerebral and mesenteric smooth muscle cells (VSMCs) of HU rats.

RESULTSROS production increased in cerebral but not in mesenteric VSMCs of HU rats compared with those in control rats. Nox2 and Nox4 protein and mRNA levels were increased significantly but MnSOD/GPx-1 mRNA levels decreased in HU rat cerebral arteries but not in mesenteric arteries. NADPH oxidases were activated significantly more in cerebral but not in mesenteric arteries of HU rats. NADPH oxidase inhibition with apocynin attenuated cerebrovascular ROS production and partially restored Nox2/Nox4 protein and mRNA levels, NADPH oxidase activity, and MnSOD/GPx-1 mRNA levels in cerebral VSMCs of HU rats.

CONCLUSIONThese results suggest that vascular NADPH oxidases regulate cerebrovascular redox status and participate in vascular oxidative stress injury during simulated microgravit.

Acetophenones ; Animals ; Cerebral Arteries ; metabolism ; Glutathione Peroxidase ; metabolism ; Hindlimb Suspension ; Male ; Membrane Glycoproteins ; metabolism ; Mesenteric Arteries ; metabolism ; Myocytes, Smooth Muscle ; metabolism ; NADPH Oxidase 2 ; NADPH Oxidase 4 ; NADPH Oxidases ; antagonists & inhibitors ; metabolism ; Rats, Sprague-Dawley ; Reactive Oxygen Species ; Superoxide Dismutase ; metabolism

Alzheimer Disease ; drug therapy ; enzymology ; Amyloid Precursor Protein Secretases ; antagonists & inhibitors ; Animals ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Humans ; Medicine, Chinese Traditional ; methods ; Membrane Glycoproteins ; antagonists & inhibitors ; Molecular Targeted Therapy ; Phytotherapy ; methods ; Presenilins ; antagonists & inhibitors

OBJECTIVETo investigate the method and mechanism for exercise-related immunosuppression via the inhibitor of NADPH oxidase diphenyleneiodonium(DPI) and glutamine supplementation and on the function of neutrophils after overtraining.

METHODSFifty male Wistar rats were randomly divided into five groups: a negative control group (C), an overtraining group (E), an overtraining + DPI intervention group (D), an overtraining+ glutamine supplementation group(G) and combined glutamine + DPI intervention group(DG). After 36 - 40 h from the last training, eight rats were randomly selected from each group, and blood was sampled from the orbital vein. ELISAs were used to measure serum cytokine levels and lipid peroxidation in blood plasma. Flow cytometry was used to measure neutrophil respiratory burst and phagocytosis. The activity of NADPH oxidase was assessed by chemiluminescence and the gene expression of gp91(phox) and p47(phox) of the NADPH-oxidase subunit was checked by Western blot.

RESULTSCompared with group C, the plasma concentrations of NO increased in group G, and the NO, cytokine-induced neutrophil chemoattractant (CINC) concentrations in group DG increased significantly. The respiratory burst and phagocytosis function of neutrophils were decreased in group E, but in group DG were increased when compared with those of group E. After overtraining the expression of gp91(phox) and p47(phox) was up regulated in group E. There were no significant changes in other groups except group DG, in which the expression of gp91(phox) was down regulated. Compared with group E, the expression of gp91(phox) and p47(phox) was up regulated in group D, group G and group DG.

CONCLUSIONThe activation of NADPH oxidase is responsible for the production of superoxide anions, which may be related to the decrease in neutrophil function after over training and is the mechanism of exercise-related immunosuppression. The DPI treatment combined glutamine supplementation can reverse the decrease neutrophils function after overtraining in vitro.

Animals ; Dietary Supplements ; Glutamine ; pharmacology ; Hyperkinesis ; physiopathology ; Male ; Membrane Glycoproteins ; metabolism ; NADPH Oxidase 2 ; NADPH Oxidases ; antagonists & inhibitors ; metabolism ; Neutrophils ; metabolism ; physiology ; Onium Compounds ; pharmacology ; Oxidation-Reduction ; Rats ; Rats, Wistar ; Respiratory Burst ; physiology

OBJECTIVEChanges of the internal and external cellular environments can induce calcium homeostasis disorder and unfolded protein aggregation in the endoplasmic reticulum (ER). This ER function disorder is called endoplasmic reticulum stress (ERS). Severe long-term ERS can trigger the ER apoptosis signaling pathway, resulting in cell apoptosis and organism injury. Recent researches revealed that ERS-induced cell death was involved in the neurocyte retrogradation in the progress of neuron degenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease and so on. Therefore, the protection effect of the traditional Chinese drug-Tiantai No. 1 (1) on the ERS injury of AD was investigated at the molecular gene level in this study with a view to explore the gene pharmacodynamic actions and mechanisms of this drug.

METHODSPrimarily cultured marrow mesenchymal stem cells (MSCs) of rats were treated by tunicamycin (TM) in order to induce ERS. RT-PCR, fluorescence immunocytochemistry and Western blot techniques were used to determine the mRNA and protein expression levels of the protective stress protein-ER molecular chaperones GRP78 and GRP94 (which would assist cells to resist cellular stress injury), and to determine the mRNA and protein expression levels of apoptosis promoting molecule Caspase-12 on the membrane of the ER, respectively.

RESULTSProtein expression levels of GRP78 and GRP94 were significantly increased in the TM-induced MSCs, and the mRNA level of Caspase-12 was also remarkably increased in the TM-induced MSCs (P<0.05). All these proved that the ERS model was successfully established by TM in MSC. Meanwhile, the mRNA and protein levels of GRP78 and GRP94 were all significantly increased compared with the model group (P<0.05 or P<0.01) after MSCs were treated with Tiantai No.1 while the mRNA and protein expression levels of Caspase-12 were significantly decreased compared with the model group (P<0.05 or P<0.01). This effect showed a dose dependent manner.

CONCLUSIONTiantai No.1 might attenuate the cell apoptosis induced by ERS injury, and thus protect the neurons against AD.

Animals ; Anti-Bacterial Agents ; antagonists & inhibitors ; pharmacology ; Cells, Cultured ; Drug Antagonism ; Drugs, Chinese Herbal ; pharmacology ; Endoplasmic Reticulum ; drug effects ; metabolism ; Gene Expression Regulation ; drug effects ; Heat-Shock Proteins ; genetics ; metabolism ; Male ; Membrane Glycoproteins ; genetics ; metabolism ; Mesenchymal Stromal Cells ; drug effects ; metabolism ; RNA ; analysis ; drug effects ; Rabbits ; Rats ; Rats, Sprague-Dawley ; Stress, Physiological ; drug effects ; genetics ; Tunicamycin ; antagonists & inhibitors ; pharmacology

Consistent non-nucleoside reverse-transcriptase inhibitors (NNRTIs) resistant HIV-1 strains occurred due to the clinical use for more than ten years of efavirenz (EFV), nevirapine (NVP), and delavirdine (DLV). In this study, we established nine cell-based pharmacological models according to most NNRTIs-resistant clinical tested strains, Resistant mutations were introduced into vector, pNL4-3.Luc.R-E-, by overlapping PCR. Then, pseudovirions were produced by co-transfection of VSV-G plasmid and pNL4-3.Luc.R-E- -mut. All nine recombinant VSVG/HIV-mut pseudovirions (VSVG/HIV-wt, VSVG/HIV(-K103N), VSVG/HIV(-Y181C), VSVG/HIV(-L100I,K103N), VSVG/HIV(-Y188L), VSVG/HIV(-K103N,Y181C), VSVG/HIV(-K103N,P225H), VSVG/HIV(-K103N,Y188L), VSVG/HIV(-K103N,G109A) and VSVG/HIV(-K103N,V108I)) had high efficient infectivity. Furthermore, they all showed resistant characteristics to EFV and NVP with IC50 changes consisting with clinical reports, not to nucleoside reverse-transcriptase inhibitors (AZT and d4T). This series safe cell-based model, which could be carried out in BSL-2 laboratory, can be used for evaluating NNRTIs candidates.
Anti-HIV Agents ; pharmacology ; Benzoxazines ; pharmacology ; Cell Line ; Delavirdine ; pharmacology ; Drug Evaluation, Preclinical ; methods ; Drug Resistance, Viral ; Genetic Vectors ; HIV Reverse Transcriptase ; antagonists & inhibitors ; genetics ; metabolism ; HIV-1 ; drug effects ; genetics ; Humans ; Membrane Glycoproteins ; genetics ; Nevirapine ; pharmacology ; Plasmids ; genetics ; Point Mutation ; Reverse Transcriptase Inhibitors ; pharmacology ; Stavudine ; pharmacology ; Transfection ; Viral Envelope Proteins ; genetics ; Virion ; genetics ; metabolism ; Virus Replication ; Zidovudine ; pharmacology

A series of aromatic aminoketones were synthesized by Mannich reaction. Structures of these compounds were confirmed by 1H NMR, MS and HRMS or element analysis. Pharmacological screening showed that most target compounds inhibited the release of beta-glucuronidase in polymorphonuclear leucocytes by PAF (platelet activating factor) and compounds MA12, MA13, MA18, MA21 and MA33 were more active. The study suggests that target compounds are potential PAF receptor antagonists and their anti-inflammatory activities are due to the inhibition of release of lysosomal enzyme.
Animals ; Anti-Inflammatory Agents ; chemical synthesis ; chemistry ; pharmacology ; therapeutic use ; Arthritis, Rheumatoid ; drug therapy ; Glucuronidase ; metabolism ; Ketones ; chemical synthesis ; chemistry ; pharmacology ; therapeutic use ; Macrophages, Peritoneal ; metabolism ; Mice ; Neutrophils ; enzymology ; Platelet Membrane Glycoproteins ; antagonists & inhibitors ; Rats ; Receptors, G-Protein-Coupled ; antagonists & inhibitors ; Structure-Activity Relationship ; Tumor Necrosis Factor-alpha ; biosynthesis

OBJECTIVEThis study aimed to investigate the roles of platelet activating factor (PAF) receptor antagonist in damage to intestinal mucin-2 (MUC2) during endotoxemia on young rats.

METHODSEighteen-day-old Wistar rats were randomized to be treated with lipopolysaccharide (LPS) (5 mg/kg), LPS plus PAF receptor antagonist and normal saline injection (control). PAF receptor antagonist BN52021 5 mg/kg was administered 30 minutes before or after LPS injection (pretreatment group or treatment group). The ileum specimens (n = 8) were harvested at 1.5, 3, 6, 24, 48 and 72 hours after LPS injection. Transmission electron microscopy was used for morphologic evaluation. Immunohistochemistry was used to determine MUC2 in intestinal mucosa.

RESULTSMicrovilli and tight junctions were intact in the control group. Enlargement of tight junctions were seen in the LPS group and microvilli were thin, rare or disrupted, shed. The rough endoplasmic reticulum, mitochondria, and glycogen particles were injured. The changes of the pretreatment and treatment group were slightly milder than that in the LPS group. Ileum of a control rat in which a thin layer of mucus covering the epithelial surface and mucin-containing goblet cells appeared very distended. The experiment group showed a decrease or irregularly distributed membranous mucus expression. The MUC2 content of absorbance significantly decreased in the LPS challenged group compared with that in the control group (P < 0.01), and reached a nadir at 6 hours (0.1841 +/- 0.0047) vs. the control group (0.2091 +/- 0.0060) (P < 0.01). The tendency of the level of MUC2 in the pretreatment and treatment group was the same as that of the LPS group, and the level of MUC2 in the pretreatment and treatment group was higher than that in the LPS group at each time point. ANOVA analysis showed that the inter-group and intra-group difference had statistical significance (P < 0.05).

CONCLUSIONSPAF may play some roles in the injury of intestinal mucus barrier function during endotoxemia. Preventive and remedial use of PAF receptor antagonist BN52021 may relieve intestinal injury.

Animals ; Endotoxemia ; metabolism ; pathology ; Intestinal Mucosa ; drug effects ; metabolism ; pathology ; Mucin-2 ; metabolism ; Platelet Membrane Glycoproteins ; antagonists & inhibitors ; Rats ; Rats, Wistar ; Receptors, G-Protein-Coupled ; antagonists & inhibitors

Xanthohumol (XH), the principal prenylflavonoid of the hop plant (Humulus lupulus L.), dose-dependently inhibited isobutylmethylxanthine (IBMX)-induced melanogenesis in B16 melanoma cells, with little cytotoxicity at the effective concentrations. Decreased melanin content was accompanied by reduced tyrosinase enzyme activity, protein and mRNA expression. The levels of tyrosinase-related protein 1 and 2 mRNAs were decreased by XH. XH also inhibited alpha-melanocyte stimulating hormone- or forskolin-induced increases in melanogenesis, suggesting an action on the cAMP-dependent melanogenic pathway. XH downregulated the protein and mRNA expression of microphthalmia-associated transcription factor (MITF), a master transcriptional regulator of key melanogenic enzymes. These results suggest that XH might act as a hypo-pigmenting agent through the downregulation of MITF in the cAMP-dependent melanogenic pathway.
1-Methyl-3-isobutylxanthine/pharmacology ; Animals ; Cell Line ; Cell Survival/drug effects ; Dose-Response Relationship, Drug ; Down-Regulation ; Drug Antagonism ; Forskolin/pharmacology ; *Humulus ; Intramolecular Oxidoreductases/antagonists & inhibitors/biosynthesis ; Melanins/antagonists & inhibitors/*biosynthesis ; Melanocytes/*drug effects/*metabolism ; Melanoma, Experimental ; Membrane Glycoproteins/antagonists & inhibitors/biosynthesis ; Mice ; Microphthalmia-Associated Transcription Factor/antagonists & inhibitors ; Monophenol Monooxygenase/antagonists & inhibitors/biosynthesis/genetics ; Oxidoreductases/antagonists & inhibitors/biosynthesis ; Propiophenones/*pharmacology ; Signal Transduction/drug effects ; alpha-MSH/metabolism