OBJECTIVETo investigate the role of heme oxygenase-1 (HO-1) and its catalyst carbon monoxide (CO) in the development of myocardial damage and the effects of zinc protoporphyrin IX (ZnPPIX), an inhibitor of HO-1 on myocardium of mice with acute viral myocarditis.

METHODSA total of 112 inbred male Balb/C mice 4 - 6 weeks of age were divided randomly into 3 groups: the control group (C group, n = 32), the viral myocarditis group (V group, n = 40) and ZnPPIX group (Z group, n = 40). The Z and V groups were inoculated intraperitoneally (i.p.) with 0.1 ml of 10(-4.36) tissue culture infectious dose 50% (TCID(50))/ml Coxsackie virus B3 (CVB(3)) to produce viral myocarditis model on day 0, C group was injected i.p. with virus-free 1640 culture culture medium 0.1 ml at the same time, then operation was done as follows: the mice of group C and group V were injected i.p. with 0.1 ml NS each day. The mice of group Z were injected i.p. with 40 micromol per kilogram of body weight ZnPPIX (HO-1 inhibitor) qod. Eight mice of each group were sacrificed on days 4, 8, 15 and 21, respectively. The blood specimens were collected by taking out the eyeballs to test for the content of carboxyhemoglobin (COHb) using spectrophotometry and cardiac troponin I (cTnI) using chemiluminescent immunoassay. The hearts tissue slides were also stained by immunohistochemistry (IHC) for HO-1 and in situ hybridization (ISH) for HO-1 mRNA. The histological and ultrastructural changes were observed under light and electron microscopes.

RESULTS(1) The histopathological changes of myocardial cells: in the V and Z groups myocardial inflammatory cells infiltration reached the peak on day 8, the Z group histopathological scores were significantly lower than those in V group on day 8 (2.40 +/- 0.31 vs. 1.73 +/- 0.24, P < 0.01) and on day 15 (1.78 +/- 0.29 vs. 1.43 +/- 0.23, P < 0.05). No inflammation was present in group C. (2) The changes of serum cTnI level in both V and Z groups were significantly higher than those in C group on day 4, 8 and 15 (P < 0.01). The level in Z group was significantly lower than that in V group on day 4 [(6.074 +/- 1.475) ng/ml vs (7.911 +/- 1.225) ng/ml, P < 0.05] and day 8 [(0.821 +/- 0.294) ng/ml vs (1.480 +/- 0.454) ng/ml, P < 0.05]. (3) The changes of blood COHb level: compared with V group, in Z group the COHb level was lower on day 4 (P < 0.05) and day 15 (P < 0.01) after CVB(3) inoculation. Surprisingly, in Z group COHb level elevated suddenly on day 8 and showed conspicuously higher than that of V group (P < 0.01). (4) The result of HO-1 IHC staining: in both V and Z group myocardial cells had positive expression, while C group did not. (5) The results of HO-1 ISH were similar to those of HO-1 IHC, the A values of group Z was significantly lower than that of group V on day 4, 15 and 21(P < 0.01), but on day 8 it was higher than that of group C (P < 0.05).

CONCLUSIONHO-1 inhibitor, ZnPP not only could inhibit HO-1 overexpression but also could induce HO-1 expression temporarily and protect against myocardial injury at the early stage of acute viral myocarditis.

Animals ; Heme Oxygenase-1 ; antagonists & inhibitors ; Male ; Mice ; Mice, Inbred BALB C ; Myocarditis ; enzymology ; metabolism ; pathology ; virology ; Myocardium ; pathology ; ultrastructure ; Protoporphyrins ; pharmacology ; Virus Diseases ; metabolism ; pathology

This study was aimed to investigate the effect of AMN107 (nilotinib) combined with heme oxygenase-1 (HO-1) inhibitor zinc protoporphyrin IX (ZnPPIX) on chronic myeloid leukemia (CML) cells and its mechanism. Proliferative rate of cells treated with AMN107 (10 µmol/L) and ZnPPIX (10 µmol/L) alone or both for different time was observed by MTT and trypan blue methods; the expression of HO-1 in the control group, ZnPPIX (10 µmol/L) group, AMN107 (10 µmol/L) group, AMN107 (10 µmol/L) combined with ZnPPIX (10 µmol/L) group was evaluated by semi-quantitative RT-PCR and Western blot at 48 h. Cell apoptosis was detected by flow cytometry with Annexin V/PI double staining at 48 h. The results showed that the strongest inhibition of cell proliferation was detected in combined group, and in a time-dependent manner; the expression level of HO-1 was lowest in combined group; the cell apoptosis rates were (11.38 ± 0.02)%, (17.44 ± 0.08)%, (39.81 ± 0.07)% and (56.46 ± 0.19)% in the control group, ZnPPIX group, AMN107 group, AMN107 combined with ZnPPIX group at 48 h respectively. It is concluded that the second-generation tyrosine kinase inhibitor AMN107 can induce the apoptosis in CML cells. Inhibition of HO-1 expression can enhance the killing effect of AMN107 on CML cells, which provides experimental evidence to further improve the clinical efficacy of CML treatment.
Apoptosis ; drug effects ; Heme Oxygenase-1 ; antagonists & inhibitors ; Humans ; K562 Cells ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; pathology ; Protoporphyrins ; pharmacology ; Pyrimidines ; pharmacology

OBJECTIVETo investigate the protective effect of overexpressed heme oxygenase-1 (HO-1) in hypoxia and the correlation between HO-1 overexpressoin and hypoxia inducible factor-1alpha (HIF-1alpha) in human hepatoma HepG2 cells.

METHODSThe expressions of HO-1 and HIF-1alpha mRNA as well as the protein were detected by RT-PCR and Western blotting, respectively. MTT assay was used to examine the relative cell survival rate. The total superoxide dismutase (SOD) activity was examined with a SOD kit.

RESULTSHypoxia induced overexpression of HO-1 gene in HepG2 cells at transcriptional and translational levels. The relative survival rate of HepG2 cells under hypoxia was significantly decreased after the HO-1 protein overexpression was inhibited by ZnPPIX (P < 0.01). The total SOD activity of cells was significantly increased after cells were treated by hypoxia for 16 hours (P < 0.05), while decreased significantly by HO-1 inhibitor ZnPPIX treatment (P < 0.01). HIF-1alpha was upregulated under hypoxia. In addition, the HO-1 overexpression under hypoxia was decreased by HIF-1alpha inhibitor, while the HIF-1alpha expression level under hypoxia was not significantly changed after HO-1 expression was inhibited by ZnPPIX.

CONCLUSIONThe overexpression of HO-1 in hypoxic HepG2 cells is HIF-1alpha-dependent or at least partly HIF-1alpha-dependent. The relative survival rate of hypoxic hepatoma cells was significantly decreased by HO-1 inhibitor treatment. The results of this study may offer new thought and drug target for the therapy of human hepatoma in the future.

Cell Hypoxia ; Cell Survival ; Heme Oxygenase-1 ; antagonists & inhibitors ; metabolism ; Hep G2 Cells ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit ; genetics ; metabolism ; Protoporphyrins ; pharmacology ; RNA, Messenger ; metabolism ; Superoxide Dismutase ; metabolism

To investigate the anti-cardiac hypertrophic mechanism of statins, thirty-eight male Wistar rats were randomly allocated to four groups. Rats in model group received nitric oxide synthase inhibitor, N-nitro-L-arginine (L-NNA) 15 mg/(kg.d) by peritoneal injection. Rats in simvastatin treatment groups were given simultaneously L-NNA as those in model group and simvastatin 5 or 30 mg/(kg.d) intragastrically respectively. Rats in control group received the same volume of normal sodium. Left ventricular function, left ventricular mass index (LVMI), the content of brain natriuretic peptide (BNP) in plasma and myocardium, myocardial hydroxyproline and heme oxygenase activity were determined after 6 weeks. The results showed that rats in model group developed significant cardiac hypertrophy associated with reduced left ventricular function compared with the control group. However, compared with the model group, L-NNA-induced cardiac hypertrophy of rats was significantly relieved in simvastatin treatment groups, associated with improved left ventricular function, decreased LVMI, lower BNP levels in plasma and myocardium, lower content of myocardial hydroxyproline, and increased myocardial heme oxygenase (HO) activity. In cultured rat neonatal cardiomyocytes, simvastatin (30 or 100 mumol/L) significantly increased heme oxygenase-1 (HO-1) mRNA expression, HO activity as well as the production of CO in cardiomyocytes. Cultured with zinc protoporphyrin, a HO inhibitor, or simvastatin alone did not change [(3)H]leucine uptake of cardiomyocytes. However, cocultured with simvastatin significantly inhibited the cardiomyocyte [(3)H]leucine uptake induced by angiotensin II in a concentration-dependent manner. Cotreatment with zinc protoporphyrin significantly abolished the suppressive effect of simvastatin on cardiomyocyte [(3)H]leucine uptake. These data suggest that the activation of HO-1/CO pathway may be one of the important mechanisms by which statins inhibit cardiac hypertrophy caused by hypertension.
Angiotensins ; antagonists & inhibitors ; pharmacology ; Animals ; Carbon Monoxide ; metabolism ; Cardiomegaly ; etiology ; prevention & control ; Cell Enlargement ; drug effects ; Heme Oxygenase-1 ; metabolism ; Hypertension ; complications ; drug therapy ; Male ; Myocytes, Cardiac ; cytology ; Rats ; Rats, Wistar ; Signal Transduction ; drug effects ; Simvastatin ; pharmacology ; therapeutic use

Periodontal disease is associated with chronic oxidative stress and inflammation. Caffeic acid phenethyl ester (CAPE), which is a potent inducer of heme oxygenase 1 (HO1), is a central active component of propolis, and the application of propolis improves periodontal status in diabetic patients. Here, primary murine macrophages were exposed to CAPE. Target gene expression was assessed by whole-genome microarray, RT-PCR and Western blotting. The antioxidative and anti-inflammatory activities of CAPE were examined by exposure of the cells to hydrogen peroxide, saliva and periodontal pathogens. The involvement of HO1 was investigated with the HO1 inhibitor tin protoporphyrin (SnPP) and knockout mice for Nrf2, which is a transcription factor for detoxifying enzymes. CAPE increased HO1 and other heat shock proteins in murine macrophages. A p38 MAPK inhibitor and Nrf2 knockout attenuated CAPE-induced HO1 expression in macrophages. CAPE exerted strong antioxidative activity. Additionally, CAPE reduced the inflammatory response to saliva and periodontal pathogens. Blocking HO1 decreased the antioxidative activity and attenuated the anti-inflammatory activity of CAPE. In conclusion, CAPE exerted its antioxidative effects through the Nrf2-mediated HO1 pathway and its anti-inflammatory effects through NF-κB inhibition. However, preclinical models evaluating the use of CAPE in periodontal inflammation are necessary in future studies.
Animals ; Caffeic Acids ; pharmacology ; Heme Oxygenase-1 ; genetics ; metabolism ; Humans ; Inflammation ; drug therapy ; Mice ; NF-kappa B ; antagonists & inhibitors ; genetics ; metabolism ; Oxidative Stress ; drug effects ; Phenylethyl Alcohol ; analogs & derivatives ; pharmacology

OBJECTIVETo investigate the effect of heme oxygenase/carbon monoxide (HO-1/CO) system on lipid deposition at aortic intima and the mechanism involved in hyperlipidemic rabbits.

METHODSTotally 32 rabbits, were divided into four groups. One group as control. Three groups for the following treatments: 1.5% cholesterol ration (Ch group, n = 8); 1.5% cholesterol ration plus HO-1 inducer hemin (Hm group, n = 8); and instead of hemin, the HO-1 inhibitor, zinc protoporphyrin IX (Zn group, n = 8) was given by injection into the abdominal cavity. Experiments were lasted for 12 weeks. Rabbit aortas were then isolated as the samples for histopathologic and ultrastructural examination. The protein expressions of HO-1 and endothelin-1 (ET-1) were investigated by immunohistochemical staining and Western blot analysis.

RESULTSComparing with the Ch group, rabbits of the Hm group showed a remarkably less extent of lipid deposition at the aortic intima [(17.9 ± 3.0)% vs (54.0 ± 4.2)%], and rabbits of the Zn group had a marked extent of lesion development [(61.1 ± 3.5)%]. Lipid deposition, endothelial damage and neo-intimal formation were less severe in rabbits of the Hm group than those in the Zn or Ch group, respectively. Comparing with the control group, rabbits of the Ch group showed a significant decrease of aortic NO production and cNOS activity. However, there were an enhancement of CO production and HO-1 activity (P < 0.01). Compared with Ch group, rabbits of the Hm group showed a remarkable elevation of aortic HO activity and CO production, whereas rabbits of the Zn group showed a marked decrease of both parameters. Compared with the Ch group, rabbits of the Hm group demonstrated a marked reduction of aorta ET-1 expression, whereas Zn group had a significantly higher ET-1 expression.

CONCLUSIONSModulation of HO-1/CO system may improve vascular endothelial function and inhibit smooth muscle cell proliferation in hypercholesterolemic rabbits, likely through a compensatory mechanism and a reduction of ET-1 expression, eventually leading to an inhibition of atherosclerotic plaque development.

Animals ; Aorta ; metabolism ; pathology ; Carbon Monoxide ; metabolism ; Cholesterol ; pharmacology ; Endothelin-1 ; metabolism ; Enzyme Inhibitors ; pharmacology ; Heme Oxygenase-1 ; antagonists & inhibitors ; metabolism ; Hemin ; pharmacology ; Hyperlipidemias ; metabolism ; pathology ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase ; metabolism ; Plaque, Atherosclerotic ; metabolism ; pathology ; prevention & control ; Protoporphyrins ; pharmacology ; Rabbits ; Tunica Intima ; metabolism ; pathology

The present study was designed to observe the protection of Grateloupia filicina polysaccharide (GFP) against hepatotoxicity induced by Dioscorea bulbifera L in mice and its underlying mechanism. GFP was intragastrically (ig) given to mice at various doses. After 6 days, the mice were treated with ethyl acetate extract of Dioscorea bulbifera L (EF, ig). Serum levels of alanine/aspartate aminotransferase (ALT/AST), alkaline phosphatase (ALP), total bilirubin (TB) were measured, and liver histological evaluation was conducted. Furthermore, reductions of liver glutathione (GSH) amount and glutamate cysteine ligase (GCL) activity were tested. The expressions of GCL-c, GCL-m, and HO-1 (heme oxygenase-1) in liver were observed by Western-blot. The results showed that GFP (600 mg x kg(-1)) decreased EF-induced the increase of serum ALT, AST and TB, and GFP (400, 600 mg x kg(-1)) inhibited EF-induced the increase of serum ALP. Liver histological evaluation showed that the liver injury induced by EF was relieved after treated with GFP. GFP further increased liver GSH amount and reversed EF-induced the decrease of GCL activity. The Western-blot result showed that GFP augmented EF-induced the increase of HO-1, and reversed EF-induced the decrease of GCL-c. In conclusion, GFP can act against the oxidative stress liver injury induced by Dioscorea bulbifera L in mice.
Alanine Transaminase ; blood ; Alkaline Phosphatase ; blood ; Animals ; Aspartate Aminotransferases ; blood ; Bilirubin ; blood ; Chemical and Drug Induced Liver Injury ; blood ; metabolism ; Dioscorea ; toxicity ; Glutamate-Cysteine Ligase ; metabolism ; Glutathione ; metabolism ; Heme Oxygenase-1 ; metabolism ; Heterocyclic Compounds, 4 or More Rings ; antagonists & inhibitors ; isolation & purification ; toxicity ; Liver ; metabolism ; pathology ; Male ; Mice ; Mice, Inbred ICR ; Oxidative Stress ; drug effects ; Plants, Medicinal ; chemistry ; Polysaccharides ; isolation & purification ; pharmacology ; Random Allocation ; Rhodophyta ; chemistry

AIMTo assess heme oxygenase-1 (HO-1) activity in the cavernous tissue of sildenafil citrate-treated rats.

METHODSOne hundred and ninety-two Sprague-Dawley male rats, divided into four equal groups, were investigated. Group 1, the control group, received regular animal chow; group 2 received sildenafil citrate by intragastric tube; group 3 received sildenafil and HO inhibitor (zinc protoporphyrin, ZnPP); and group 4 received sildenafil and nitric oxide synthase (NOS) inhibitor L-nitroarginine methyl ester (L-NAME). Twelve rats from each group were killed after 0.5 h, 1 h, 2 h and 3 h of drug administration. Then HO-1 activity, cGMP levels and NOS enzymatic activity in the cavernous tissues were estimated.

RESULTSIn cavernous tissue, HO-1 activity, NOS enzymatic activity and cGMP concentration increased significantly in sildenafil-treated rats compared to other groups throughout the experiment. Rats receiving either HO or NOS inhibitors showed a significant decrease in these parameters. HO-1 cavernous tissue activity and NOS enzymatic activity demonstrated a positive significant correlation with cGMP levels (r = 0.646, r = 0.612 respectively; P < 0.001).

CONCLUSIONThe actions of PDE5 inhibitor sildenafil citrate in the cavernous tissue are partly mediated through the interdependent relationship between both HO-1 and NOS activities.

Administration, Oral ; Animals ; Cyclic GMP ; metabolism ; Drug Interactions ; Drug Therapy, Combination ; Enzyme Inhibitors ; pharmacology ; Heme Oxygenase-1 ; antagonists & inhibitors ; metabolism ; Male ; NG-Nitroarginine Methyl Ester ; pharmacology ; Nitric Oxide Synthase ; metabolism ; Penis ; drug effects ; enzymology ; Piperazines ; pharmacology ; Protoporphyrins ; pharmacology ; Purines ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Sildenafil Citrate ; Sulfones ; pharmacology ; Vasodilator Agents ; pharmacology

To explore the role of heme oxygenase (HO)-1 experimental system in dachengqitang (DD) ameliorating ALI induced by lipopolysaccharide (LPS) in mice. Seventy-five male Kunming mice were randomly divided into control group (normal saline was instilled intratracheally(50 microL/per mouse), LPS group (LPS was instilled intratracheally to replicate ALI model), DD + LPS group, DD + LPS + ZnPP (ZnPP, HO-1 specific inhibitor) group and the DD group. Mice were killed at 6 h after administration. Lung indexes were tested; lung histomorphological changes were observed under microscope, and neutrophils (PMN) number and protein content of bronchoalveolar lavage fluid (BALF) were measured; HO-1 mRNA and protein expression in lung tissue were detected by RT-PCR and Western blot. The results showed that intratracheal instillation of LPS in mice can cause significant morphological changes in lung tissue. Both PMN numbers and protein content in BALF were increased. meanwhile the expressions of HO-1 mRNA and protein in lung tissue were increased. Pretreated with DD and then intratracheally instillated LPS coulde ameliorat lung tissue injury, reduced PMN BALF number and protein content, but increase HO-1 mRNA and protein expression in the lung tissue when compared with LPS. HO-1 inhibitor ZnPP coulde inhibite the ameliorative effect of DD. The results suggest that the ameliorative effect of DD on ALI induced by LPS in mice were related with upregulation HO-1 mRNA and protein.
Acute Lung Injury ; chemically induced ; prevention & control ; Animals ; Blotting, Western ; Bronchoalveolar Lavage Fluid ; chemistry ; cytology ; Gene Expression Regulation, Enzymologic ; drug effects ; Heme Oxygenase-1 ; antagonists & inhibitors ; genetics ; metabolism ; Leukocyte Count ; Lipopolysaccharides ; Lung ; drug effects ; enzymology ; pathology ; Male ; Mice ; Neutrophils ; cytology ; drug effects ; Phytotherapy ; methods ; Plant Extracts ; pharmacology ; Proteins ; metabolism ; Protoporphyrins ; pharmacology ; Random Allocation ; Reverse Transcriptase Polymerase Chain Reaction ; Treatment Outcome

We evaluated the effect of cobalt chloride (CoCl2) on TNF-alpha and IFN-gamma-induced-inflammation and reactive oxygen species (ROS) in renal tubular epithelial cells (HK-2 cells). We treated HK-2 cells with CoCl2 before the administration of TNF-alpha/IFN-gamma. To regulate hemeoxygenase-1 (HO-1) expression, the cells were treated CoCl2 or HO-1 siRNA. CoCl2 reduced the generation of ROS induced by TNF-alpha/IFN-gamma. TNF-alpha/IFN-gamma-treated-cells showed an increase in the nuclear translocation of phosphorylated NF-kappaBp65 protein, the DNA-binding activity of NF-kappaBp50 and NF-kappaB transcriptional activity and a decrease in IkappaBalpha protein expression. These changes were restored by CoCl2. We noted an intense increase in monocyte chemoattractant protein-1 (MCP-1) and regulated on activation normal T cell expressed and secreted (RANTES) production in TNF-alpha/IFN-gamma-treated cells. We demonstrated that this effect was mediated through NF-kappaB signaling because an NF-kappaB inhibitor significantly reduced MCP-1 and RANTES production. CoCl2 effectively reduced MCP-1 and RANTES production. The expression of HO-1 was increased by CoCl2 and decreased by HO-1 siRNA. However, knockdown of HO-1 by RNA interference did not affect MCP-1 or RANTES production. We suggest that CoCl2 has a protective effect on TNF-alpha/IFN-gamma-induced inflammation through the inhibition of NF-kappaB and ROS in HK-2 cells. However, CoCl2 appears to act in an HO-1-independent manner.
Cell Line ; Chemokine CCL2/metabolism ; Chemokine CCL5/metabolism ; Cobalt/*pharmacology ; Epithelial Cells/cytology/metabolism ; Heme Oxygenase-1/antagonists & inhibitors/genetics/metabolism ; Humans ; *Inflammation ; Interferon-gamma/pharmacology ; Kidney Tubules, Proximal/cytology ; NF-kappa B/antagonists & inhibitors/genetics/*metabolism ; NF-kappa B p50 Subunit/genetics/metabolism ; Oxidative Stress/*drug effects ; Phosphorylation ; Protein Binding ; RNA Interference ; RNA, Small Interfering/metabolism ; Transcription Factor RelA/metabolism ; Tumor Necrosis Factor-alpha/pharmacology