Inhibitory effects of hyperoxia and methemoglobinemia on H(2)S induced ventilatory stimulation in the rat

The aim of this study was to clarify, using in vitro and in vivo approaches in the rat, the site of mediation of the inhibition of H(2)S induced arterial chemoreceptor stimulation, by hyperoxia and methemoglobinemia. We first determined the ventilatory dose-response curves during intravenous injections of H(2)S. A very high dose of NaHS, i.e. 0.4 μmol (concentration: 800 μM), was needed to stimulate breathing within 1s following i.v. injection. Above this level (and up to 2.4 μmol, with a concentration of 4800 μM), a dose-dependent effect of H(2)S injection was observed. NaHS injection into the thoracic aorta produced the same effect, suggesting that within one circulatory time, H(2)S pulmonary exchange does not dramatically reduce H(2)S concentrations in the arterial blood. The ventilatory response to H(2)S was abolished in the presence of MetHb (12.8%) and was significantly depressed in hyperoxia and, surprisingly, in 10% hypoxia. MetHb per se did not affect the ventilatory response to hypoxia or hyperoxia, but dramatically enhanced the oxidation of H(2)S in vitro, with very fast kinetics. These findings suggest that, the decrease/oxidation of exogenous H(2)S in the blood is the primary effect of MetHb in vivo. In contrast, the in vitro oxidative properties of blood for H(2)S were not affected by the level of [Formula: see text] between 23 and >760 mmHg. This suggests that the inhibition of the ventilatory response to H(2)S by hyperoxia during aortic or venous injection originates within the CB and not in the blood. The implications of these results on the role of endogenous H(2)S in the arterial chemoreflex are discussed.

The effect of nanoparticles in rats during critical periods of pregnancy

BACKGROUND AND OBJECTIVE. Nanotechnology works with substances at a nanometer scale, and it offers many solutions for biomedicine. Nanoparticles (NPs) have been shown as effective agents for imaging, drug delivery, pathogen detection, etc. However, to date, NP toxicity is poorly known. The aim of our study was to investigate the embryotoxicity and teratogenicity of quantum dots (QDs) at the different stages of rat embryogenesis. MATERIALS AND METHODS. Wistar rats were injected with CdSe/ZnS or CdTe QDs on the 6th, 13th, and 18th days of embryogenesis. Cyclophosphamide was chosen as a positive control of embryotoxicity. On the 21st day, the number of resorptions, weight, length, and external malformations of the embryos were estimated. Fluorescence spectroscopy and microscopy analysis were used to determine the accumulation of QDs in the tissues. RESULTS. Exposure to cyclophosphamide during the pregnancy decreased the embryonic weight and length when compared with the control group and produced numerous malformations. The effects depended on the stage of embryogenesis. Meanwhile, QDs did not cause any embryotoxic or teratogenic effects. However, CdTe QDs induced necrosis in the tissues of the peritoneal cavity. The necrotic tissues contained QDs with altered spectroscopic properties. Spectroscopic and microscopic tissue examination revealed that QDs accumulated in the placenta, but no penetration to the embryonic tissues was observed. CONCLUSIONS. QDs did not cause any direct embryotoxic or teratogenic effects, but they had adverse effects on the maternal organism. The observed QD effects and the long-term accumulation of QDs in the maternal organism may increase the risk of adverse effects on embryo development.

[Study on the effect of realgar nanoparticles anti-adenovirus in vitro]

OBJECTIVE

This study was to establish a model that adenovirus type 3 (HAdV-3) infected on Hep-2 cell in order to explore anti-adenovirus3 (HAdV-3) effect of Chinese medicine realgar in vitro.

METHOD

Use high-energy ball milling with distilled water to prepare realgar nanoparticles. The concentration of nanometer realgar was tested by molybdenum blue staining method and realgar nanoparticles' particle size was tested on Nano Series. The technique of cell culture with ribavirin as positiv control was to observe anti-adenovirus effect through prevention, treatment and direct inactivation of three kinds of drug delivery.

RESULT

This drug was found to be a potential inhibitor of HAdV-3 in a concentration-dependent manner with the median toxic concentration (TC50) of 0.649 microg/ml in Hep-2 Cell culture. The median inhibition concentration (IC50) was 0.255 microg/ml when drug was added before infection. The IC50 was 0.142 microg/ml when drug was added after virus infection, and it was 0.117 microg/ml as the drug was added after it mixed with virus. The therapeutic index (TI) was 2.55, 4.57 and 5.55 respectively.

CONCLUSION

The direct inactivation effect of realgar nanoparticles is the most evident in three drug deliveries manner with the same concentration in vitro.

Hydrogen sulfide inhibits the spontaneous and oxytocin-induced contractility of human pregnant myometrium

Hydrogen sulfide (H(2)S) is a novel endogenous gaseous signaling transmitter in mammalian tissues including smooth muscle tissues. We investigated the effect of sodium hydrosulfide (NaHS), a H(2)S donor, on the contractility of isolated human myometrium strips from term pregnant women who were undergoing labor. Cumulative effects of NaHS on spontaneous and oxytocin-induced contractility were evaluated by using isometric tension recordings. NaHS (0.1 μM-1 mM) concentration dependently inhibited spontaneous contractility of laboring myometrium, with a decrease in amplitude and frequency. NaHS (0.1 μM-1 mM) decreased the frequency but not the amplitude of oxytocin (1 μM)-induced contractions. NaHS-induced relaxation could be prevented by pretreatment with glibenclamide, an inhibitor of K(+)(ATP) channels. Thus, NaHS evokes relaxation of human pregnant myometrium, suggesting a possible role of H(2)S during human pregnancy.

[Toxicity study of realgar]

OBJECTIVE

To investigate the toxicity of realgar and provide the scientific basis for safety use of realgar in clinic.

METHOD

Acute toxicity was tested by single oral administration. Chronic toxicity of realgar was tested at different dose levels (5, 10, 20, 80, 160 mg x kg(-1) x d(-1)) which correspond to 1/2, 1, 2, 8, 16 times of human dose levels. The rats were treated with the test substances through oral administration once daily for successively 90 days. Urinary qualitative test, blood routine examination, serum chemistry measurement, and histomorphologic observation were conducted at day 30, 60 and 90. Toxic changes related to the treatment of realgar and no-observed adverse effect level (NOAEL) was evaluated.

RESULT

With the content of 90% total arsenic and 1.696 mg x g(-1) soluble asenic, LD50 of Realgar with oral administration was 20.5 g x kg(-1) (corresponding to 34.8 mg x kg(-1) soluble arsenic), equivalent to 12 812 times of clinical daily dose for an adult. Realgar can cause kidney toxicity or/and liver toxicity after administration for over 30, 60 or 90 days respectively. The kidney was more sensitive to realgar than liver. Based on repeated dose toxicity study, NOAELs were 160 mg x kg(-1) x d(-1) for 30 day's administration, 20 mg x kg(-1) x d(-1) for 60 day's administration, 10 mg x kg(-1) x d(-1) mg x kg(-1) x d(-1) for 90 day's administration respectively. Thus, for safety use of realgar, it is recommended that the daily doses of realgar (with soluble arsenic < or = 1.7 mg x g(-1)) for an adult of the body weight about 60 kg could be 10-160 mg depending on the variation of the treatment duration.

CONCLUSION

Long term use of realgar can cause kidney and liver pathological change, so the doses and administration duration should be limited. The suggestion is as follows: realgar which contains soluble arsenic < or = 1.7 mg x g(-1) should be used less than 2 weeks at daily dose 160 mg, less than 4 weeks at the dose of 20 mg and less than 6 weeks at the dose of 10 mg.

[Asenic accumulation following realgar administration in rats]

OBJECTIVE

To explore arsenic accumulation and toxicity mechanism following long-term use of realgar and provide scientific basis for safety use of realgar in clinic.

METHOD

The realgar which was used in the study contains 90% insoluble asenic sulfide (As2S2) and 1.696 mg x kg(-1) soluble arsenic. Two separate experiments were performed: 1) Twenty-eight fasting SD rats were orally given a single dose of realgar at the dose of 0.8 g x kg(-1) and the other four rats were given ultra-filtrated water served as control group. Blood, hearts, livers, kidneys, lungs and brains of four rats were taken out at 0.5, 1, 2, 4, 8, 16, 36 h respectively after treatment. Asenic quantity of each organ or blood sample was measured. 2) Forty SD rats were randomly divided into four groups: control group and realgar 0.02, 0.08, 0.16 g x kg(-1) groups, each group containing 5 females and 5 males. The rats were intra-gastrically treated with realgar once a day for successively 90 days, while the control group was given ultra-filtrated water. Asenic amount in blood, liver, kidney and brain of each rat was measured in fasting rats at 16 h after last dosing.

RESULT

Asenic amount of blood, liver, kidney, heart, lung and brain increased after single dosing of realgar at dose of 0.16 g x kg(-1), with the order from high to low blood > kidney > lung > liver > heart > brain. Asenic amount was much higher in blood than that in other organs. The feature of asenic distribution in blood following realgar administration may be the basis for its use for leukemia Ninety-day oral treatment of realgar led to significant accumulation of asenic in blood, kidney, liver and brain. The highest asenic accumulation times was found in kidney followed by liver, which was assumed to be associated with nephrotoxicity and hepatotoxicity of realgar. The highest amount of asenic was observed in blood after 90 day's administration of realgar, and the amount of asenic in organs was in the order of blood > kidney > liver > brain.

CONCLUSION

Asenic can be absorbed and extensively distributed in various organs or tissesses after realgar administration in rats. Long-term use of realgar caused high asenic accumulation in various tissueses, including blood, kidney, liver, and brain. The nephrotoxicity and hepatotoxicity of realgar could be associated with the asenic accumulation in relative organs. Blood is the target of the most highest distribution and accamulation of asenic after realgar treatment, that could be associated with the efficacy of realgar on the treatment of leakemia.

Tetradecylthioacetic acid increases hepatic mitochondrial β-oxidation and alters fatty acid composition in a mouse model of chronic inflammation

The administration of tetradecylthioacetic acid (TTA), a hypolipidemic and anti-inflammatory modified bioactive fatty acid, has in several experiments based on high fat diets been shown to improve lipid transport and utilization. It was suggested that increased mitochondrial and peroxisomal fatty acid oxidation in the liver of Wistar rats results in reduced plasma triacylglycerol (TAG) levels. Here we assessed the potential of TTA to prevent tumor necrosis factor (TNF) α-induced lipid modifications in human TNFα (hTNFα) transgenic mice. These mice are characterized by reduced β-oxidation and changed fatty acid composition in the liver. The effect of dietary treatment with TTA on persistent, low-grade hTNFα overexpression in mice showed a beneficial effect through decreasing TAG plasma concentrations and positively affecting saturated and monounsaturated fatty acid proportions in the liver, leading to an increased anti-inflammatory fatty acid index in this group. We also observed an increase of mitochondrial β-oxidation in the livers of TTA treated mice. Concomitantly, there were enhanced plasma levels of carnitine, acetyl carnitine, propionyl carnitine, and octanoyl carnitine, no changed levels in trimethyllysine and palmitoyl carnitine, and a decreased level of the precursor for carnitine, called γ-butyrobetaine. Nevertheless, TTA administration led to increased hepatic TAG levels that warrant further investigations to ascertain that TTA may be a promising candidate for use in the amelioration of inflammatory disorders characterized by changed lipid metabolism due to raised TNFα levels.

Neuroprotection by the selective iNOS inhibitor GW274150 in a model of Parkinson disease

Neuroinflammation and the activation of inducible nitric oxide synthase (iNOS) have been proposed to play a role in the pathogenesis of Parkinson disease (PD). In this study we investigated the effects of the selective iNOS inhibitor GW274150 in the 6-OHDA model of PD. 6-OHDA administration was associated with increased numbers of cells expressing iNOS. Administration of the iNOS inhibitor twice daily for 7 days, beginning 2 days after the 6-OHDA lesioning, led to a significant neuroprotection as shown by assessment of the integrity of the nigrostriatal system by tyrosine hydroxylase immunocytochemistry and HPLC assessment of striatal dopamine content. However, GW274150 displayed a bell-shaped neuroprotective profile, being ineffective at high doses. 6-OHDA lesioning was associated with an increase in microglial activation as assessed by the MHC II antigen OX-6 and the number of matrix metalloproteinase 9 (MMP-9)-immunopositive cells. NO is a known modulator of MMP-9, and iNOS inhibition was associated with decreased numbers of MMP-9-immunopositive cells, culminating in a reduction in the numbers of reactive microglia. Withdrawal of GW274150 for a further 7 days negated any neuroprotective effects of iNOS inhibition, suggesting that the damaging effects of inflammation last beyond 7 days in this model and the continued administration of the drug may be required.

An oil-free microemulsion for intravenous delivery of diallyl trisulfide: formulation and evaluation

The aim of the present study was to develop an oil-free o/w microemulsion, Cremophor EL:ethanol-propylene glycol:saline, for diallyl trisulfide (DATS) for intravenous (i.v.) administration to modify the safety and pharmacokinetics of DATS. The ternary diagram was constructed to identify the regions of dilutable microemulsions, and the optimal composition of microemulsion was determined by evaluation of injection safety such as hemolysis, intravenous stimulation and injection anaphylaxis compared to commercial formulation Chentian(®). Promising microemulsion with modified injection safety was developed that could incorporate 100 mg/g of DATS. The droplet size of the microemulsion was about 26 nm in diameter with narrow distribution (polydispersity index: 0.14). Acute toxicity test showed that median lethal dose (LD(50)) of DATS microemulsion was 1.69-fold higher than that of Chentian(®). Pharmacokinetics was assessed by comparing with the commercial injection after intravenous administration to rats at a dose of 30 mg/kg. The developed microemulsion showed significant higher area under the drug concentration-time curve and lower clearance and distribution volume than those of Chentian(®) (p<0.05). This helped DATS to reach higher level in vessel, and circulate in the blood stream for a longer time resulting in better therapeutic effect. In conclusion, microemulsion would be a promising intravenous delivery system for DATS.

Lu-AA21004, a multimodal serotonergic agent, for the potential treatment of depression and anxiety

Lu-AA21004, an oral, multimodal serotonergic agent, is currently under development by H Lundbeck and Takeda Pharmaceutical, for the potential treatment of depression and anxiety. Lu-AA21004 belongs to a novel chemical class of antidepressant agents, the bisarylsulfanyl amines, and possesses a novel pharmacological profile, with activity at serotonergic receptors 5-HT3, 5-HT7 and 5-HT1A, and also at the 5-HT transporter. Acute administration of Lu-AA21004 in rats inhibited the firing activity of serotonergic neurons of the dorsal raphe nucleus through 5-HT3 receptor blockade, with rapid recovery of firing activity upon cessation of treatment compared with an antidepressant of the SSRI class. Results from phase II clinical trials have reported improvement in depression and anxiety symptoms after 6 weeks of treatment. Lu-AA21004 was generally well tolerated, with adverse events related to sexual dysfunction occurring in a lower number of patients receiving Lu-AA21004 compared with venlafaxine. Phase III clinical trials with Lu-AA21004 in patients with major depressive disorder are underway and phase III trials in patients with generalized anxiety disorder have been completed. If initial outcomes from these clinical trials prove positive, Lu-AA21004 may pave the way for new multimodal therapies for the treatment of depression and anxiety.

Cardioprotective effects of hydrogen sulfide

The gaseous mediator hydrogen sulfide (H(2)S) is synthesized mainly by cystathionine γ-lyase in the heart and plays a role in the regulation of cardiovascular homeostasis. Here we first overview the state of the art in the literature on the cardioprotective effects of H(2)S in various models of cardiac injury. Subsequently, we present original data showing the beneficial effects of parenteral administration of a donor of H(2)S on myocardial and endothelial function during reperfusion in a canine experimental model of cardiopulmonary bypass. Overview of the literature demonstrates that various formulations of H(2)S exert cardioprotective effects in cultured cells, isolated hearts and various rodent and large animal models of regional or global myocardial ischemia and heart failure. In addition, the production of H(2)S plays a role in myocardial pre- and post-conditioning responses. The pathways implicated in the cardioprotective action of H(2)S are multiple and involve K(ATP) channels, regulation of mitochondrial respiration, and regulation of cytoprotective genes such as Nrf-2. In the experimental part of the current article, we demonstrate the cardioprotective effects of H(2)S in a canine model of cardiopulmonary bypass surgery. Anesthetized dogs were subjected hypothermic cardiopulmonary bypass with 60 min of hypothermic cardiac arrest in the presence of either saline (control, n=8), or H(2)S infusion (1 mg/kg/h for 2 h). Left ventricular hemodynamic variables (via combined pressure-volume-conductance catheter) as well as coronary blood flow, endothelium-dependent vasodilatation to acetylcholine and endothelium-independent vasodilatation to sodium nitroprusside were measured at baseline and after 60 min of reperfusion. Ex vivo vascular function and high-energy phosphate contents were also measured. H(2)S led to a significantly better recovery of preload recruitable stroke work (p<0.05) after 60 min of reperfusion. Coronary blood flow was also significantly higher in the H(2)S group (p<0.05). While the vasodilatory response to sodium nitroprusside was similar in both groups, acetylcholine resulted in a significantly higher increase in coronary blood flow in the H(2)S-treated group (p<0.05) both in vivo and ex vivo. Furthermore, high-energy phosphate contents were better preserved in the H(2)S group. Additionally, the cytoprotective effects of H(2)S were confirmed also using in vitro cell culture experiments in H9c2 cardiac myocytes exposed to hypoxia and reoxygenation or to the cytotoxic oxidant hydrogen peroxide. Thus, therapeutic administration of H(2)S exerts cardioprotective effects in a variety of experimental models, including a significant improvement of the recovery of myocardial and endothelial function in a canine model of cardiopulmonary bypass with hypothermic cardiac arrest.

Cardiac contractile dysfunction and apoptosis in streptozotocin-induced diabetic rats are ameliorated by garlic oil supplementation

Previous studies have suggested that garlic oil could protect the cardiovascular system. However, the mechanism by which garlic oil protects diabetes-induced cardiomyopathy is unclear. In this study, streptozotocin (STZ)-induced diabetic rats received garlic oil (0, 10, 50, or 100 mg/kg of body weight) by gastric gavage every 2 days for 16 days. Normal rats without diabetes were used as control. Cardiac contractile dysfunction examined by echocardiography and apoptosis evaluated by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay were observed in diabetic rat hearts. Additionally, a shift in cardiac myosin heavy chain (MHC) gene expression from α- to β-MHC isoform, decreased levels of superoxide dismutase-1 (SOD-1) and cardiac α-actin, and elevated cardiac thiobarbituric acid reactive substances (TBARS) and caspase- and p38-NFκB-leading apoptosis signaling activities were demonstrated in diabetic hearts. However, these diabetes-related cardiac dysfunctions were almost dose-dependently ameliorated by garlic oil administration. In conclusion, garlic oil possesses significant potential for protecting hearts from diabetes-induced cardiomyopathy.

[Pharmacokinetics of bacteria bioleaching solution of realgar in rat]

The paper is to report the preparation of realgar bioleaching solution (RBS) by bacteria and the comparison of pharmacokinetics of RBS and H3AsO3 (ATO), and the study of its possible change of absorption and distribution of soluble arsenic in rat. The experiment was carried out on Wistar rats given peritoneal injection of RBS at a dose of 0.3 mg x kg(-1) (soluble arsenic content, 0.3 mg x kg(-1)), and rats given ATO at the dose of 0.3 mg x kg(-1) (soluble arsenic content, 0.3 mg x kg(-1)). The arsenic concentrations in many tissues including heart, liver, spleen, lung, renal and brain were determined. The changes of pharmacokinetic parameters and arsenic distribution in different tissues were detected and compared in these two groups of rats. The pharmacokinetic parameters of RBS and ATO are very similar. There is very few distribution of arsenic in the tissues in RBS group, compared with the ATO group. There is significant difference in the content of arsenic between two groups statistically (P < 0.01). It is feasible that we select the bacteria bioleaching solution as a candidate drug, which may be employed for primary change of arsenic compounds including dissolved inorganic arsenic and organic arsenic, in order to improve bioavailability and decrease the amount of arsenic accumulation in animal tissues. In addition, there is significant difference in the change of arsenic compounds between two groups. It can be concluded that, the investigation on application of microbial technology may provide a basis for exploratory research of realgar.

[The inhibitory effects of Realgar bioleaching solution on S180 ascites-tumor and its toxicity]

OBJECTIVE

To investigate the inhibitory effect of Realgar bioleaching solution (RBS) on tumor S180 cells line and estimate its toxicity, to provide experimental evidence for the further exploit of Realgar.

METHODS

24 hours after the models of ascites-tumor bearing mice were established, the mice were injected RBS once a day. The survival rates of S180 ascites-tumor bearing mice injected in RBS was studied, and the RBS acute toxicity of mice produced by oral, intraperitoneal or intravenous was evaluated by Drug Median Lethal Dose (LD50).

RESULTS

The inhibitory effect of S180 cells in vivo had a dose-dependent manner. The survival rates of mice were 10% - 60% in the different dose in 15 days. The LD50 values of RBS by oral, intraperitoneal or intravenous were 5.27 mg/kg, 3.63 mg/kg and 2.68 mg/kg, respectively.

CONCLUSION

RBS has potent antitumor effect, LD50 value of RBS is lower than that of traditional medicine.

Effects of L-cysteine on Ni-Cu sulfide and marmatite bioleaching by Acidithiobacillus caldus

The effect of L-cysteine in different concentrations on the bioleaching of Ni-Cu sulfide and marmatite were studied with a moderately thermophilic, sulfur-oxidizing bacterium, strain of Acidithiobacillus caldus. X-ray diffraction (XRD) observations showed the change of bioleached solid residues and the effect of L-cysteine on the surface charges of minerals. It was found that adding certain amounts of L-cysteine to the leaching system of Ni-Cu sulfide largely enhanced the leaching rate, while L-cysteine inhibited the bioleaching of marmatite by A. caldus. The mechanism of L-cysteine interaction with mineral surfaces was studied by means of zeta potential determination and IR spectra.

Endogenous hydrogen sulfide reduces airway inflammation and remodeling in a rat model of asthma

Endogenous hydrogen sulfide (H(2)S) is hypothesized to have an important role in systemic inflammation. We investigated if endogenous H(2)S may be a crucial mediator in airway inflammation and airway remodeling in a rat model of asthma and if endogenous H(2)S may exert its anti-inflammatory effect by inhibiting inducible nitric oxide synthase (iNOS)/NO pathway. Cystathionine-gamma-lyase (CSE; a H(2)S-synthesizing enzyme) was mainly expressed in airway and vascular smooth muscle cells in rat lung tissue. Levels of endogenous H(2)S was decreased in pulmonary tissue in ovalbumin (OVA)-treated rats. Exogenous administration of NaHS alleviated airway inflammation and airway remodeling: peak expiratory flow (PEF) increased, goblet cell hyperplasia and collagen deposition score decreased, with decreased total cells recovered from bronchoalveolar fluid (BALF) and influx of eosinophils and neutrophils. The H(2)S levels of serum and lung tissue were positively correlated with PEF and negatively correlated with the level of eosinophils and neutrophils in BALF, score of lung pathology. NaHS treatment significantly attenuated pulmonary iNOS activation in OVA-treated rats. These results suggest that the CSE/H(2)S pathway plays an anti-inflammatory and anti-remodeling part in asthma pathogenesis and could be a novel target in prevention and treatment of asthma.

[Effects of hydrogen sulfide on vascular inflammation in pulmonary hypertension induced by high pulmonary blood flow: experiment with rats]

OBJECTIVE

To investigate the effects of hydrogen sulfide (H2S) on vascular inflammation in pulmonary hypertension induced by high pulmonary blood flow.

METHODS

Forty-four male SD rats were randomly divided into 8 groups: 4-week control group (n = 7), 4-week shunt group (n = 7), 4-week shunt + propargylglycine (PPG, an endogenous H2S release inhibitor) intraperitoneal injection group (n = 8), 11-week control group (n = 7), 11-week shunt group (n = 7), and 11-week shunt + sodium hydrosulfide (NaHS, a H2S donor) intraperitoneal injection group (n = 8). Right ventricular catheterization was used to measure the mean pulmonary arterial pressure (mPAP). Immunohistochemistry was used to detect the expression of inflammatory related factor intercellular adhesion molecule-1 (ICAM-1), and the key molecules of nuclear factor-kappaB (NF-kappaB) signal transduction pathway, including NF-kappaB p65 and inhibitor of NF-kappaB (IkappaBalpha), in the pulmonary artery, and ELISA was used to detect the concentrations of the inflammatory related factors, including ICAM-1, interleukin-8 (IL-8), and monocyte chemoattractant protein-1 (MCP-1) in blood plasma and lung tissues so as to reflect the corresponding inflammatory responsiveness.

RESULTS

The plasma and lung tissue ICAM-1, IL-8 and MCP-1 contents of the 4-week shunt group were all significantly higher than those of the 4-week control group (P < 0.05 or P < 0.01). The mPAP of the 4 week shunt + PPG group was (20.3 +/- 1.7) mm Hg, significantly higher than that of the 4-week shunt group [(16.2 +/- 1.5) mm Hg, P < 0.01]. The expression levels of ICAM-1 and NF-kappaB p65 in the small and median pulmonary artery endothelin cells of the 4-week shunt + PPG group were both significantly stronger than those of the 4-week shunt group (P < 0.05 or P < 0.01), whereas the expression of IkappaBalpha was weaker than that of the 4-week shunt group (P < 0.05). The plasma IL-8 content of the 4-week shunt + PPG group was (148 +/- 29) micromol/L, significantly higher than that of the 4 week-shunt group [(118 +/- 23) micromol/L, P < 0.05], and the lung tissue ICAM-1 and MCP-1 levels of the 4-week shunt + PPG group were (27.3 +/- 5.0) micromol/g and (12.9 +/- 1.1) micromol/g respectively, both significantly higher than those of the 4-week shunt group [(21.9 +/- 2.1) and (10.2 +/- 1.4) micromol/g respectively, both P < 0.05]. The mPAP and expression levels of ICAM-1 and NF-kappaB p65 of the large, median, and small pulmonary artery endothelia cells of the 11-week shunt group were all higher than those of the 11-week control group (P < 0.05 or P < 0.01), whereas the expression levels of IkappaBalpha were all less obvious (P < 0.05 or P < 0.01). The plasma and lung tissue ICAM-1, IL-8, and MCP-1 levels of the 11-week shunt group were all significantly higher than those of the 11-week control group (all P < 0.01). The mPAP of the 11 week shunt + NaHS group was (23.2 +/- 3.0) mm Hg, significantly lower than that of the 11-week shunt group [(27.5 +/- 1.9) mm Hg, P < 0.05]. The ICAM-1 and NF-kappaB p65 expression levels of large, median, and small pulmonary artery endothelia cells of the 11-week shunt + NaHS group were all significantly weaker than those of the 11-week shunt group (P < 0.05 or P < 0.01), whereas the protein expression levels of IkappaBalpha in small and median pulmonary artery endothelia cells of the 11-week shunt + NaHS group were significantly higher than those of the 11-week shunt group (both P < 0.05). The plasma and lung tissue ICAM-1 contents of the 11-week shunt + NaHS group were (124 +/- 11) micromol/L and (19.9 +/- 2.5) micromol/g, both significantly lower than those of the 11-week shunt group [(154 +/- 20) micromol/L and (23.9 +/- 3.6) micromol/g respectively, both P < 0.01]. The plasma and lung tissue IL-8 contents of the 11-week shunt + NaHS group were (92 +/- 11) micromol/L and (15.0 +/- 1.7) micromol/g, both significantly lower than those of the 11-week shunt group [(121 +/- 17) micromol/L and (19.0 +/- 3.9) micromol/g respectively, both P < 0.01]. The lung tissue MCP-1 content of the 11-week shunt + NaHS group was (10.8 +/- 1.6) micromol/g, significantly lower than that of the 11-week shunt group [(13.5 +/- 1.4) micromol/g, P < 0.01].

CONCLUSION

H2S attenuates the development of pulmonary hypertension induced by high pulmonary blood flow through ameliorating pulmonary vascular inflammation. The inhibitory effect of H2S on the pulmonary vascular inflammation involves elevating IkappaBalpha expression, down-regulating NF-kappaB p65 expression and then inhibiting the expression of inflammatory related factors.

[The role of hydrogen sulfide in acute lung injury during endotoxic shock and its relationship with nitric oxide and carbon monoxide]

OBJECTIVE

To explore the role of hydrogen sulfide (H2S) in acute lung injury (ALI) during endotoxic shock (ES) and its relationship with nitric oxide (NO) and carbon monoxide (CO).

METHODS

Sixty-four adult male SD rats were randomly divided into 4 equal groups: control group injected with normal saline via the caudal vein, lipopolysaccharide (LPS)-treated group injected with LPS to establish ES model, LPS + NaHS group injected with LPS and sodium hydrosulfide (NaHS, an exogenous H2S donor], and LPS + PPG group injected with LPS and polypropylene glycol (PPG, a H2S synthase inhibitor). The mean artery pressure (MAP) was measured via a polyethylene catheter in the right common carotid artery for 6 h. Then the rats were sacrificed with their lungs taken out to determine the lung water content, lung tissue malonyldialdehyde (MDA), NO, and CO contents, as well as lung tissue cystathionine-gamma-lyase (CSE), myeloperoxidase (MPO), nitric oxide synthase (NOS), and heme oxygenase (HO) activities. The H2S content in blood plasma was detected also. Morphological changes of the lung tissues were observed under light microscope and the index of quantitative assessment (IQA) of lung injury was calculated. Immunohistochemistry and Western blotting were used to detect the lung tissue inducible NOS (iNOS) and HO-1 protein expression.

RESULTS

Compared with the control group, the MAP of the LPS group was significantly lower, the pathological changes in lung tissue was more obvious, and the IQA, lung water content, lung MDA content, lung MPO and CSE activities as well as plasma H2S content were all significantly higher (P < 0.05 or P < 0.01). Compared to the LPS group, the plasma H2S and lung CSE activity of the LPS + NaHS group were higher, the lung injury was more severe, and the MAP was lower. And compared to the LPS group, the MAP of the LPS + PPG group was higher, and the lung injury was milder (both P < 0.05). The eNOS activity in the lung tissue of the LPS group was (5.26 +/- 0.25) Uxmg(-1)xprot(-1), significantly lower than that of the control group [(6.45 +/- 0.42) Uxmg(-1)xprot(-1)]; and the iNOS activity and NO content of the LPS group were (12.6 +/- 0.6) Uxmg(-1)xprot(-1) and (144 +/- 25) micromol/L respectively, both higher than those of the control group [(10.5 +/- 0.7) Uxmg(-1)xprot(-1) and (68 +/- 5) micromol/L respectively] (P < 0.05 or P < 0.01). Compared with the LPS group, the lung tissue eNOS activity of the LPS + PPG group was significantly higher, and the iNOS activity [(10.2 +/- 0.4) Uxmg(-1)xprot(-1)], iNOS protein expression, and NO content [(74 +/- 5) micromol/L]were all significantly lower (P < 0.05 or P < 0.01). Compared with the LPS group, the lung tissue eNOS activity of the LPS + NaHS group [(4.81 +/- 0.23) Uxmg(-1)xprot(-1)] was significantly lower, and the iNOS activity [(14.6 +/- 0.4) Uxmg(-1)xprot(-1)], iNOS protein expression, and NO content [(217 +/- 18) micromol/L] were significantly higher (P < 0.05 or P < 0.01). The lung tissue HO activity [(173 +/- 31) pkat/g], HO protein expression, and CO content [(3.63 +/- 0.24)%] of the LPS group were all significantly higher than those of the control group [(125 +/- 22) pkat/g, (2.48 +/- 0.33)%, both P < 0.05], and the LPS + PPG group [(88 +/- 17) pkat/g, (2.98 +/- 0.23)%, both P < 0.05]. Compared to the LPS group, the lung tissue HO activity [(263 +/- 37) pkat/g], HO protein expression, and CO content [(4.35 +/- 0.32)%] of the LPS + NaHS group were all significantly higher (all P < 0.05).

CONCLUSION

The increase of H(2)S generation participates in the lung tissue injury during ES and this event is related to eNOS activity decrease, iNOS activity increase that causes the production of large amount of NO. H2S up-regulates the HO-1/CO system in the lung tissues during ES, which may be the endogenous compensatory response against the injury.

[Effect of additional chromosome abnormalities on the outcome of newly diagnosed acute promyelocytic leukemia treated with red arsenic sulfide and all trans-retinoic acid plus anthracyclin based protocol]

OBJECTIVE

To analyze the effect of additional chromosome abnormalities on the prognosis and the clinical manifestations of acute promyelocytic leukemia (APL) and the reaction of the patients with additional chromosomes to the treatment of combination of red arsenic sulfide, all trans-retinoic acid (ATRA) and anthracyclin.

METHODS

The clinical data of 158 patients with newly diagnosed APL who were treated with combination of red arsenic sulfide, ATRA, and anthracyclin were analyzed retrospectively.

RESULTS

The frequency of additional chromosome abnormalities in the APL patients was 18.4%, and trisomy 8 and i17q- were the most to be seen. The disseminated intravascular coagulation rate of the patients with additional chromosome abnormality was 62.1%, significantly higher than that of the patients without additional chromosome abnormality (35.6%, P < 0.05). The complete remission rate of the patients with additional chromosome abnormality was 75.9%, not significantly lower than that of those without additional chromosome abnormality (90.7%), and the relapse rate and incidence rate of central nervous system leukemia were 13.8% and 17.2%, both higher, but not significantly, than those of the patients without additional chromosome abnormality (6.2% and 6.2% respectively) (all P > 0.05). There was no significant difference in survival rate between these 2 groups (P = 0.160).

CONCLUSION

Additional chromosome abnormality does not significantly influence the prognosis of APL treated with combination of red arsenic sulfide, ATRA, and anthracyclin.

Inhibition of acrylamide toxicity in mice by three dietary constituents

The inhibitory effects of three dietary constituents, tea polyphenols, resveratrol, and diallyl trisulfide, on acrylamide-biomacromolecule (liver DNA, protamine, and hemoglobin) adduct formation at human exposure level were studied by accelerator mass spectrometry. The results demonstrated that the three dietary constituents all significantly inhibited the formation of acrylamide adducts with liver DNA, whereas tea polyphenols and diallyl trisulfide reduced protamine and hemoglobin adducts, respectively. Further biochemical studies showed that acrylamide could significantly inactivate creatine kinase and glutathione S-transferase and deplete glutathione. When the inhibitors were cotreated with acrylamide, all of them could effectively recover the activities of creatine kinase. In addition, tea polyphenols and diallyl trisulfide could increase glutathione S-transferase activity remarkably. On the basis of these results, mechanisms of the effects are discussed. This study might provide a beneficial guide to people's diet for the purpose of reducing the harmful effect of acrylamide.

Long term treatment with tetradecylthioacetic acid improves the antioxidant status in obese Zucker (fa/fa) rats

Increased oxidative stress was observed in obese Zucker rats. Treatment of obese rats with tetradecylthioacetic acid for 12 weeks increased the H(2)O(2)-production, but decreased plasma malondialdehyde, changed the serum fatty acid profile, increased liver fatty acid binding protein mRNA, and lowered serum insulin, thereby enhancing the antioxidant defense system.

MN 001: KCA 757, KCA-757, MN-001

MN 001 is an orally bioavailable anti-inflammatory agent, originated by Kyorin Pharmaceutical, which is being developed in clinical trials by the US company MediciNova for the treatment of interstitial cystitis and asthma. Kyorin is developing the drug as KCA 757 for these indications. The actions of the drug are described by MediciNova as consisting of eosinophil migration inhibition, leukotriene antagonism, and phosphodiesterase IV inhibition. Other mechanisms described for MN 001 include the inhibition of phosphodiesterases III, 5-lipoxy-genase, phospholipase C as well as thromboxane A2. Development of an immediate-release formulation of MN 001 has been discontinued. An extended-release formulation remains in development. MediciNova is looking for partnering/outlicensing opportunities for MN 001 in North America and Europe. MediciNova licensed MN 001 from Kyorin Pharmaceutical in March 2002, and now holds exclusive worldwide rights, excluding Japan, China, Taiwan and South Korea, to develop and commercialise the drug. The phase III clinical programme of immediate-release MN 001 was initiated by Medicinova in the US in November 2006. In the first phase III trial, 705 patients with mild to moderate asthma were to be randomised to receive MN 001 (750 mg twice daily, 500 mg three times daily) or placebo for 12 weeks. The change from baseline in mean forced expiratory volume in 1 second (FEV(1)) will be the primary endpoint. The primary endpoint was met in a phase II study of MN 001 in patients with mild to moderate asthma. The trial evaluated the efficacy of three different doses of MN 001 for the treatment of asthma. Results have been reported. MediciNova has received Notices of Allowance from the US Patent and Trademark Office for three patent applications covering certain compositions, uses and manufacturing processes associated with MN 001. MN 001 has received patent protection through at least 2023.

A bioactively modified fatty acid improves survival and impairs metastasis in preclinical models of acute leukemia

PURPOSE

Polyunsaturated fatty acids (PUFA) and the sulfur-substituted fatty acid tetradecylthioacetic acid (TTA) inhibit proliferation and induce apoptosis in lymphoma and leukemic cell lines, but it is unknown if they can modify leukemogenesis in the intact organism.

EXPERIMENTAL DESIGN

We now examined the effects of PUFA and TTA in rats transplanted with either acute promyelocytic leukemia or acute T-cell leukemia. The rats were randomized to isoenergetic diets containing either lard (control), omega3 (n-3) PUFA, or TTA.

RESULTS

Whereas TTA prolonged survival (P < 0.05) in both types of rat leukemia, n-3 PUFA had no significant effect compared with controls. Only TTA inhibited (P < 0.05) leukemic infiltration in the bone marrow and spleen, probably due to apoptosis of the leukemic cells. Plasma metalloproteinase activity, a marker of metastatic activity, was significantly reduced in TTA-fed rats only.

CONCLUSIONS

Dietary intake of TTA, but not of n-3 PUFA, in rats with acute leukemia, prolonged their survival. TTA intake was also associated with reduced leukemic cell burden as well as diminished extramedullar dissemination. TTA represents a modified fatty acid that exerts unique effects on malignant hematopoietic cells, and the present study indicates that TTA may have a therapeutic potential in patients with acute leukemias.

Use of lime sulphur and itraconazole to treat shelter cats naturally infected with Microsporum canis in an annex facility: an open field trial

Dermatophytosis is the most common contagious and infectious skin disease of cats. It is of particular importance in animal shelters because it is a known zoonosis, highly contagious, and easily transmitted. In this open clinical trial, 58 cats with confirmed Microsporum canis dermatophytosis and 32 uninfected bonded pairs or littermates were treated with a combination of 21 days of oral itraconazole (10 mg kg(-1)) and twice weekly lime sulphur rinses until cured. Cats were not clipped in this treatment programme. Fungal cultures were obtained once weekly on all cats, and cats were considered cured when they had two consecutive negative weekly fungal cultures. Cats were held in the facility and received continued topical treatment until the fungal cultures were finalized. None of the cats developed oral ulcerations as a result of grooming the lime sulphur rinses. Oral ulcerations only developed in cats with clinical signs associated with upper respiratory disease. None of the uninfected cats living in contact with infected cats became culture positive or developed skin lesions. When data were examined retrospectively and the number of days to finalize the cultures was subtracted (21 days) from the total number of days the cats were housed in the annex, the mean number of days of treatment required for cure was 18.4 +/- 9.5 SEM (range 10-49 days). Cats with more severe infections required longer therapy. In this shelter, the combination of oral itraconazole and topical lime sulphur rinses for the treatment of dermatophytosis was effective and safe.