Low dose aspirin prevents endothelial dysfunction in the aorta and foetal loss in pregnant mice infected with influenza A virus

Influenza A virus (IAV) infection in pregnancy resembles a preeclamptic phenotype characterised by vascular dysfunction and foetal growth retardation. Given that low dose aspirin (ASA) is safe in pregnancy and is used to prevent preeclampsia, we investigated whether ASA or NO-conjugated aspirin, NCX4016, resolve vascular inflammation and function to improve offspring outcomes following IAV infection in pregnant mice. Pregnant mice were intranasally infected with a mouse adapted IAV strain (Hkx31; 104 plaque forming units) and received daily treatments with either 200µg/kg ASA or NCX4016 via oral gavage. Mice were then culled and the maternal lungs and aortas collected for qPCR analysis, and wire myography was performed on aortic rings to assess endothelial and vascular smooth muscle functionality. Pup and placentas were weighed and pup growth rates and survival assessed. IAV infected mice had an impaired endothelial dependent relaxation response to ACh in the aorta, which was prevented by ASA and NCX4016 treatment. ASA and NCX4016 treatment prevented IAV dissemination and inflammation of the aorta as well as improving the pup placental ratios in utero, survival and growth rates at post-natal day 5. Low dose ASA is safe to use during pregnancy for preeclampsia and this study demonstrates that ASA may prove a promising treatment for averting the significant vascular complications associated with influenza infection during pregnancy.

An Aspirin-Free Versus Dual Antiplatelet Strategy for Coronary Stenting: STOPDAPT-3 Randomized Trial

BACKGROUND

Bleeding rates on dual antiplatelet therapy (DAPT) within 1 month after percutaneous coronary intervention (PCI) remain high in clinical practice, particularly in patients with acute coronary syndrome or high bleeding risk. Aspirin-free strategy might result in lower bleeding early after PCI without increasing cardiovascular events, but its efficacy and safety have not yet been proven in randomized trials.

METHODS

We randomly assigned 6002 patients with acute coronary syndrome or high bleeding risk just before PCI either to prasugrel (3.75 mg/day) monotherapy or to DAPT with aspirin (81-100 mg/day) and prasugrel (3.75 mg/day) after loading of 20 mg of prasugrel in both groups. The coprimary end points were major bleeding (Bleeding Academic Research Consortium 3 or 5) for superiority and cardiovascular events (a composite of cardiovascular death, myocardial infarction, definite stent thrombosis, or ischemic stroke) for noninferiority with a relative 50% margin.

RESULTS

The full analysis set population consisted of 5966 patients (no-aspirin group, 2984 patients; DAPT group, 2982 patients; age, 71.6±11.7 years; men, 76.6%; acute coronary syndrome, 75.0%). Within 7 days before randomization, aspirin alone, aspirin with P2Y12 inhibitor, oral anticoagulants, and intravenous heparin infusion were given in 21.3%, 6.4%, 8.9%, and 24.5%, respectively. Adherence to the protocol-specified antiplatelet therapy was 88% in both groups at 1 month. At 1 month, the no-aspirin group was not superior to the DAPT group for the coprimary bleeding end point (4.47% and 4.71%; hazard ratio, 0.95 [95% CI, 0.75-1.20]; Psuperiority=0.66). The no-aspirin group was noninferior to the DAPT group for the coprimary cardiovascular end point (4.12% and 3.69%; hazard ratio, 1.12 [95% CI, 0.87-1.45]; Pnoninferiority=0.01). There was no difference in net adverse clinical outcomes and each component of coprimary cardiovascular end point. There was an excess of any unplanned coronary revascularization (1.05% and 0.57%; hazard ratio, 1.83 [95%CI, 1.01-3.30]) and subacute definite or probable stent thrombosis (0.58% and 0.17%; hazard ratio, 3.40 [95% CI, 1.26-9.23]) in the no-aspirin group compared with the DAPT group.

CONCLUSIONS

The aspirin-free strategy using low-dose prasugrel compared with the DAPT strategy failed to attest superiority for major bleeding within 1 month after PCI but was noninferior for cardiovascular events within 1 month after PCI. However, the aspirin-free strategy was associated with a signal suggesting an excess of coronary events.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT04609111.

Multi-Omics Approaches for Liver Reveal the Thromboprophylaxis Mechanism of Aspirin Eugenol Ester in Rat Thrombosis Model

Aspirin eugenol ester (AEE) is a novel medicinal compound synthesized by esterifying aspirin with eugenol using the pro-drug principle. Pharmacological and pharmacodynamic experiments showed that AEE had excellent thromboprophylaxis and inhibition of platelet aggregation. This study aimed to investigate the effect of AEE on the liver of thrombosed rats to reveal its mechanism of thromboprophylaxis. Therefore, a multi-omics approach was used to analyze the liver. Transcriptome results showed 132 differentially expressed genes (DEGs) in the AEE group compared to the model group. Proteome results showed that 159 differentially expressed proteins (DEPs) were identified in the AEE group compared to the model group. Six proteins including fibrinogen alpha chain (Fga), fibrinogen gamma chain (Fgg), fibrinogen beta chain (Fgb), orosomucoid 1 (Orm1), hemopexin (Hpx), and kininogen-2 (Kng2) were selected for parallel reaction monitoring (PRM) analysis. The results showed that the expression of all six proteins was upregulated in the model group compared with the control group. In turn, AEE reversed the upregulation trend of these proteins to some degree. Metabolome results showed that 17 metabolites were upregulated and 38 were downregulated in the model group compared to the control group. AEE could reverse the expression of these metabolites to some degree and make them back to normal levels. The metabolites were mainly involved in metabolic pathways, including linoleic acid metabolism, arachidonic acid metabolism, and the tricarboxylic acid (TCA) cycle. Comprehensive analyses showed that AEE could prevent thrombosis by inhibiting platelet activation, decreasing inflammation, and regulating amino acid and energy metabolism. In conclusion, AEE can have a positive effect on thrombosis-related diseases.

Molecular Mechanisms of Cytotoxicty of NCX4040, the Non-Steroidal Anti-Inflammatory NO-Donor, in Human Ovarian Cancer Cells

NCX4040, the non-steroidal anti-inflammatory-NO donor, is cytotoxic to several human tumors, including ovarian tumor cells. We have found that NCX4040 is also cytotoxic against both OVCAR-8 and its adriamycin resistant (NCI/ADR-RES) tumor cell lines. Here, we have examined mechanism(s) for the cytotoxicity of NCX4040 in OVCAR-8 and NCI/ADR-RES cell lines. We found that NCX4040 induced significant apoptosis in both cell lines. Furthermore, NCX4040 treatment caused significant depletion of cellular glutathione, causing oxidative stress due to the formation of reactive oxygen/nitrogen species (ROS/RNS). Significantly more ROS/RNS were detected in OVCAR-8 cells than in NCI/ADR-RES cells which may have resulted from increased activities of SOD, glutathione peroxidase and transferases expressed in NCI/ADR-RES cells. NCX4040 treatment resulted in the formation of double-strand DNA breaks in both cells; however, more of these DNA breaks were detected in OVCAR-8 cells. RT-PCR studies indicated that NCX4040-induced DNA damage was not repaired as efficiently in NCI/ADR-RES cells as in OVCAR-8 cells which may lead to a differential cell death. Pretreatment of OVCAR-8 cells with N-acetylcysteine (NAC) significantly decreased cytotoxicity of NCX4040 in OVCAR-8 cells; however, NAC had no effects on NCX4040 cytotoxicity in NCI/ADR-RES cells. In contrast, FeTPPS, a peroxynitrite scavenger, completely blocked NCX4040-induced cell death in both cells, suggesting that NCX4040-induced cell death could be mediated by peroxynitrite formed from NCX4040 following cellular metabolism.

Validation of the EDAN SA-10 ambulatory blood pressure monitor in general population according to the Association for the Advancement of Medical Instrumentation/European Society of Hypertension/International Organization for Standardization Universal Standard

OBJECTIVE

To evaluate the accuracy of the EDAN SA-10 oscillometric upper-arm professional office ambulatory blood pressure (BP) monitor in general population according to the Association for the Advancement of Medical Instrumentation (AAMI)/European Society of Hypertension (ESH)/International Organization for Standardization (ISO) Universal Standard (ISO 81060-2:2018).

METHODS

Subjects were recruited according to the AAMI/ESH/ISO Universal Standard using the same arm sequential BP measurement method. Four cuffs of the test device were used for arm circumference 16-21.5 cm (extra small), 20.5-28 cm (small), 27-35 cm (medium), and 34-43 cm (large).

RESULTS

A total of 105 subjects were recruited, and 97 subjects were included in the final analysis. For validation criterion 1, the mean ± SD of the differences between the test device and reference BP readings was -0.59 ± 4.04/-1.79 ± 4.39 mmHg (systolic/diastolic). For criterion 2, the SD of the averaged BP differences between the test device and reference BP per subject was 3.10/3.80 mmHg (systolic/diastolic).

CONCLUSION

The EDAN SA-10 upper-arm ambulatory BP monitor has passed all the requirements of the AAMI/ESH/ISO Universal Standard (ISO 81060-2:2018) in general population and can be recommended for clinical use.

Aspirin eugenol ester alleviates lipopolysaccharide-induced acute lung injury in rats while stabilizing serum metabolites levels

Aspirin eugenol ester (AEE) was a novel drug compound with aspirin and eugenol esterified. AEE had various pharmacological activities, such as anti-inflammatory, antipyretic, analgesic, anti-oxidative stress and so on. In this study, it was aimed to investigate the effect of AEE on the acute lung injury (ALI) induced by lipopolysaccharide (LPS) in rats. In vitro experiments evaluated the protective effect of AEE on the LPS-induced A549 cells. The tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) were measured in the cell supernatant. The Wistar rats were randomly divided into five groups (n = 8): control group, model group (LPS group), LPS + AEE group (AEE, 54 mg·kg−1), LPS + AEE group (AEE, 108 mg·kg−1), LPS + AEE group (AEE, 216 mg·kg−1). The lung wet-to-dry weight (W/D) ratio and immune organ index were calculated. WBCs were counted in bronchoalveolar lavage fluid (BALF) and total protein concentration was measured. Hematoxylin-Eosin (HE) staining of lung tissue was performed. Glutathione (GSH), glutathione peroxidase (GPx), catalase (CAT), antioxidant superoxide dismutase (SOD), total antioxidant capacity (T-AOC), lactate dehydrogenase (LDH), C-reactive protein (CRP), myeloperoxidase (MPO), malondialdehyde (MDA), macrophage mobility inhibitory factor (MIF), TNF-α, IL-6, and IL-1β activity were measured. The metabolomic analysis of rat serum was performed by UPLC-QTOF-MS/MS. From the results, compared with LPS group, AEE improved histopathological changes, reduced MDA, CRP, MPO, MDA, and MIF production, decreased WBC count and total protein content in BALF, pro-inflammatory cytokine levels, immune organ index and lung wet-dry weight (W/D), increased antioxidant enzyme activity, in a dose-dependent manner. The results of serum metabolomic analysis showed that the LPS-induced ALI caused metabolic disorders and oxidative stress in rats, while AEE could ameliorate it to some extent. Therefore, AEE could alleviate LPS-induced ALI in rats by regulating abnormal inflammatory responses, slowing down oxidative stress, and modulating energy metabolism.

Pharmacokinetics, pharmacodynamics and safety evaluation of 5,5'-methylenebis(2-acetoxybenzoic acid) in dogs following intravenous administration

Complement-mediated intravascular hemolysis occurs in canine immune-mediated hemolytic anemia (IMHA). Complement inhibitors might enhance treatment of this disease. Dimers of acetylsalicylic acid such as 5,5'-methylenebis(2-acetoxybenzoic acid) (DAS) have been reported to inhibit complement. This study aimed to characterize the pharmacokinetics and safety profile of a single 3 mg/kg IV dose of DAS in 6 healthy mixed-breed dogs. Serum concentrations of DAS and its primary metabolites were measured by liquid chromatography-tandem mass spectrometry at baseline and at 5, 10 and 30 min, and 1, 2, 4, 6, 8, 12, 18 and 24 h post-administration. Additional blood samples were collected 7 and 14 days after drug administration. Complete blood counts, serum chemistry panels, C-reactive protein measurements, coagulation testing and cytokine analyses were used for safety monitoring. Following IV administration of 3 mg/kg DAS, the estimated mean maximum plasma concentration was 54,709 ng/mL. Pharmacokinetic modeling suggested that DAS was eliminated with a half-life value of 8.1 h, equivalent to a clearance of 6.93 L/hr kg and a volume of distribution of 56 mL/kg. Plasma concentrations of the metabolites were measured rapidly (within 15-60 min for M1 and M2 respectively). Overall, the relative exposure to M1 and M2 suggest significant biotransformation of DAS occurred, but DAS was the most abundant circulating species. No adverse clinical reactions were noted following DAS administration and safety studies suggested DAS caused no inflammatory response or coagulation disturbance. Further clinical evaluation of DAS is warranted.

A retrospective study on long-term efficacy of intranasal lysine-aspirin in controlling NSAID-exacerbated respiratory disease

Purpose

Aspirin treatment after desensitization (ATAD) represents an effective therapeutic option suitable for NSAID-exacerbated respiratory disease (N-ERD) patients with recalcitrant disease. Intranasal administration of lysine-aspirin (LAS) has been suggested as a safer and faster route than oral ATAD but evidence for its use is less strong. We investigated nasal LAS therapy long-term efficacy based on objective outcomes, smell function, polyp recurrence and need for surgery or rescue therapy. Clinical biomarkers predicting response to intranasal LAS, long-term side effects and consequences of discontinuing treatment have been evaluated.

Methods

A retrospective analysis of a database of 60 N-ERD patients seen between 2012 and 2020 was performed in March 2021. They were followed up at 3-months, 1-, 2- and 3-years with upper and lower airway functions assessed at each follow-up.

Results

Higher nasal airflow and smell scores were found at each follow-up in patients taking LAS (p < 0.001 and p = 0.048 respectively). No influence of LAS on pulmonary function measurements was observed. Patient on intranasal LAS showed a lower rate of revision sinus surgery when compared to those who discontinued the treatment (p < 0.001). None of the variables studied was found to influence LAS treatment response.

Conclusion

Our study demonstrates the clinical effectiveness of long-term intranasal LAS in the management of N-ERD in terms of improved nasal airflow and olfaction and a reduced need for revision sinus surgery. Intranasal LAS is safe, being associated with a lower rate of side effects when compared to oral ATAD. However, discontinuation of the treatment at any stage is associated with a loss of clinical benefit.

Aspirin eugenol ester ameliorates paraquat-induced oxidative damage through ROS/p38-MAPK-mediated mitochondrial apoptosis pathway

Paraquat (PQ) is an effective and commercially important herbicide that is widely used worldwide. However, PQ is highly toxic and can cause various complications and acute organ damage. Aspirin eugenol ester (AEE) is a potential new compound with anti-inflammatory and antioxidant stress pharmacological activity. The present study was to reveal the therapeutic effects and the protective effect of AEE against PQ-induced acute lung injury (ALI) with the help of PQ-induced oxidative damage in A549 cells and PQ-induced lung injury in rats. AEE might have no significant therapeutic effect on PQ-induced lung injury in rats. However, AEE had a significant protective effect on PQ-induced lung injury in rats. AEE pretreatment significantly reduced the stimulatory effect of PQ on malondialdehyde (MDA), the inhibitory effect of PQ on catalase (CAT) activity, superoxide dismutase (SOD) activity, glutathione peroxidase (GPx) activity, the ratio of GSH/GSSH, the activity of caspase-3 and the overexpression of p38 mitogen-activated protein kinase (MAPK) phosphorylation in vivo. In vitro, A549 cells were treated with 250 μM PQ for 24 h. Incubation of A549 cells with PQ led to apoptosis, and increased the level of superoxide anions, reactive oxygen species (ROS), malondialdehyde and the activity of caspase-3 and up-regulation of phosphorylated p38-MAPK, reduced mitochondrial membrane potential (ΔΨm) and the activity of SOD. However, after 24 h on AEE pretreatment of A549 cells, the above-mentioned adverse reactions caused by PQ were significantly alleviated. In addition, AEE pretreatment reduced p38-MAPK phosphorylation in PQ-treated A549 cells. SB203580, the specific p38-MAPK inhibitor, and p38-MAPK shRNA attenuated the activation of the p38-MAPK signaling pathway. N-acetylcysteine (NAC) reduced the level of phosphorylated p38-MAPK and the production of intracellular ROS and inhibited apoptosis. The results showed that AEE may inhibit PQ-induced cell damage through ROS/p38-MAPK-mediated mitochondrial apoptosis pathway.

Resveratrol and Resveratrol-Aspirin Hybrid Compounds as Potent Intestinal Anti-Inflammatory and Anti-Tumor Drugs

Resveratrol (3,4,5-Trihydroxy-trans-stilbene) is a naturally occurring polyphenol that exhibits beneficial pleiotropic health effects. It is one of the most promising natural molecules in the prevention and treatment of chronic diseases and autoimmune disorders. One of the key limitations in the clinical use of resveratrol is its extensive metabolic processing to its glucuronides and sulfates. It has been estimated that around 75% of this polyphenol is excreted via feces and urine. To possibly alleviate the extensive metabolic processing and improve bioavailability, we have added segments of acetylsalicylic acid to resveratrol in an attempt to maintain the functional properties of both. We initially characterized resveratrol-aspirin derivatives as products that can inhibit cytochrome P450 Family 1 Subfamily A Member 1 (CYP1A1) activity, DNA methyltransferase (DNMT) activity, and cyclooxygenase (COX) activity. In this study, we provide a detailed analysis of how resveratrol and its aspirin derivatives can inhibit nuclear factor kappa B (NFκB) activation, cytokine production, the growth rate of cancer cells, and in vivo alleviate intestinal inflammation and tumor growth. We identified resveratrol derivatives C3 and C11 as closely preserving resveratrol bioactivities of growth inhibition of cancer cells, inhibition of NFκB activation, activation of sirtuin, and 5’ adenosine monophosphate-activated protein kinase (AMPK) activity. We speculate that the aspirin derivatives of resveratrol would be more metabolically stable, resulting in increased efficacy for treating immune disorders and as an anti-cancer agent.

Exploring the Potential of Nitric Oxide and Hydrogen Sulfide (NOSH)-Releasing Synthetic Compounds as Novel Priming Agents against Drought Stress in Medicago sativa Plants

Land plants are continuously exposed to multiple abiotic stress factors like drought, heat, and salinity. Nitric oxide (NO) and hydrogen sulfide (H₂S) are two well-examined signaling molecules that act as priming agents, regulating the response of plants to stressful conditions. Several chemical donors exist that provide plants with NO and H₂S separately. NOSH is a remarkable novel donor as it can donate NO and H₂S simultaneously to plants, while NOSH-aspirin additionally provides the pharmaceutical molecule acetylsalicylic acid. The current study aimed to investigate the potential synergistic effect of these molecules in drought-stressed Medicago sativa L. plants by following a pharmacological approach. Plants were initially pre-treated with both donors (NOSH and NOSH-aspirin) via foliar spraying, and were then subsequently exposed to a moderate water deficit while NO and H₂S inhibitors (cPTIO and HA, respectively) were also employed. Phenotypic and physiological data showed that pre-treatment with NOSH synthetic compounds induced acclimation to subsequent drought stress and improved the recovery following rewatering. This was accompanied by modified reactive-oxygen and nitrogen-species signaling and metabolism, as well as attenuation of cellular damage, as evidenced by altered lipid peroxidation and proline accumulation levels. Furthermore, real-time RT-qPCR analysis revealed the differential regulation of multiple defense-related transcripts, including antioxidant enzymes. Overall, the present study proposed a novel role for NOSH compounds as efficient plant priming agents against environmental constraints through the coordinated regulation of multiple defense components, thus opening new horizons in the field of chemical priming research toward the use of target-selected compounds for stress tolerance enhancement.

Nitro aspirin (NCX4040) induces apoptosis in PC3 metastatic prostate cancer cells via hydrogen peroxide (H2O2)-mediated oxidative stress

Non-steroidal anti-inflammatory drugs (NSAID) have shown promise as anticancer agents by inducing cell death apart from their antipyretic, anti-inflammatory and anti-thrombogenic effects. In our current study, we investigated the oxidative stress mediated cell death mechanism of a NSAID derivative NCX4040 (a nitric oxide (NO) releasing form of aspirin) in castration-resistant prostate cancer (CRPC) PC3 cell line. Our data revealed that NCX4040 is more potent than its parent compound aspirin or NO releasing compound DETA NONOate. NCX4040 significantly induced hydrogen peroxide formation with ensuing oxidative stress and mitochondrial depolarization resulting in lipid peroxidation, cell cycle arrest, inhibition of colony growth and induction of apoptosis in PC3 cells. Moreover, NCX4040 inhibited migration potential of PC3 cells by depolymerizing F-actin and promoting anoikis. Interestingly, elevated levels of NADPH oxidase 1 (NOX1), superoxide dismutase (SOD) 1 and 2 were observed upon NCX4040 treatment. However, down regulation of anti-apoptotic markers B-cell lymphoma 2 (Bcl2) and anti-oxidant thioredoxin reductase 1 (TXNRD1) expression were observed. In addition, NCX4040 down regulated cyclin D1 expression in PC3 cells further supporting the anticancer effect of NCX4040. Western blot analysis revealed that significant down regulation of key anti-apoptotic markers such as cellular inhibitor of apoptosis protein-1 (cIAP1), X-linked inhibitor of apoptosis (XIAP), survivin, and Cellular-Myc (c-Myc). On the other hand, NCX4040-treated cells showed upregulation of phosho histone H2AX (pH2AX), cleaved caspase3 and cleaved Poly [ADP-ribose] polymerase 1 (PARP1). Taken together, our data demonstrate that NCX4040 treatment enhances free radical formation which in turn induces oxidative stress leading to mitochondrial mediated cell death in metastatic PC3 cells.

Aspirin Derivative 5-(Bis(3-methylbut-2-enyl)amino)-2-hydroxybenzoic Acid Improves Thermotolerance via Stress Response Proteins in Caenorhabditis elegans

Aging is a major risk factor for many prevalent diseases. Pharmacological intervention to improve the health span and extend the lifespan could be a preventive elixir for aging and age-related diseases. The non-steroid anti-inflammation medicine aspirin was reported to delay aging in Caenorhabditis elegans (C. elegans) and mice. We are wondering if the analogues of aspirin could also present antiaging activity. Here, we synthesized several aspirin derivatives and investigated their thermotolerance and antiaging effect in C. elegans. One of the compounds, 5-(bis(3-methylbut-2-en-1-yl)amino)-2-hydroxybenzoic acid, moderately increased the survival of C. elegans under heat stress, but could not extend the lifespan under optimum conditions. This compound could increase the mRNA level of stress response gene gst-4, and the mRNA and protein expression level of heat shock protein hsp-16.2 under heat stress. The failure of activating the transcription factor DAF-16 might explain why this compound could not act as aspirin to extend the lifespan of C. elegans. Our results would help further the investigation of the pharmacological activity of aspirin analogues and the relationship between structures and activity.

Nitroaspirin plus clopidogrel versus aspirin plus clopidogrel against platelet thromboembolism and intimal thickening in mice

Clopidogrel plus aspirin is the treatment of choice for patients undergoing percutaneous, coronary interventions with stenting, but it does not prevent restenosis. NCX-4016, a nitric oxide-releasing aspirin (nitroaspirin), exerts a wider range of antiplatelet actions compared to aspirin, superior antithrombotic activity and reduces restenosis after arterial injury in animals. The aim of the present study was to compare the combination of nitroaspirin plus clopidogrel with aspirin plus clopidogrel in a model of platelet pulmonary thromboembolism, bleeding and intimal thickening in mice. Drugs were administered orally for 5 days; the antithrombotic effects were evaluated against collagen plus epinephrine-induced pulmonary thromboembolism, the haemorrhagic effects by tail transection bleeding time and the effects on neointima proliferation by histomorphology of photochemically injured femoral arteries. Lung platelet emboli were reduced significantly and more effectively by nitroaspirin plus clopidogrel (-56%, p< 0.05 vs control) than by aspirin plus clopidogrel (-26%, p< 0.05 vs control). Ex vivo platelet aggregation was inhibited maximally by nitroaspirin plus clopidogrel. Aspirin plus clopidogrel strikingly prolonged the bleeding time while nitroaspirin plus clopidogrel induced a lesser prolongation. Nitroaspirin plus clopidogrel significantly reduced intimal thickening of the femoral artery while aspirin plus clopidogrel was ineffective. Nitroaspirin plus clopidogrel is more effective and less prohaemorrhagic than aspirin plus clopidogrel in mice; provided these data are confirmed in other animal models, nitroaspirin plus clopidogrel may represent a new regimen to be tested in patients undergoing coronary revascularization procedures.

Changes in Somatostatin-Like Immunoreactivity in the Sympathetic Neurons Projecting to the Prepyloric Area of the Porcine Stomach Induced by Selected Pathological Conditions

The aim of the present study was to define changes in the expression of somatostatin (SOM) in the sympathetic perikarya innervating the porcine stomach prepyloric area during acetylsalicylic-acid-induced gastritis (ASA) and experimentally induced hyperacidity (HCL) and following partial stomach resection (RES). On day 1, the stomachs were injected with neuronal retrograde tracer Fast Blue (FB). Animals in the ASA group were given acetylsalicylic acid orally for 21 days. On the 22nd day after FB injection, partial stomach resection was performed in RES animals. On day 23, HCL animals were intragastrically given 5 ml/kg of body weight of a 0.25 M aqueous solution of hydrochloric acid. On day 28, all pigs were euthanized. Then, 14-μm thick cryostat sections of the coeliac-superior mesenteric ganglion (CSMG) complexes were processed for routine double-labelling immunofluorescence. All pathological conditions studied resulted in upregulation of SOM-like (SOM-LI) immunoreactivity (from 14.97 ± 1.57% in control group to 33.72 ± 4.39% in the ASA group, to 39.02 ± 3.65% in the RES group, and to 29.63 ± 0.85% in the HCL group). The present studies showed that altered expression of SOM occurs in sympathetic neurons supplying the prepyloric area of the porcine stomach during adaptation to various pathological insults.

Aspalatone Prevents VEGF-Induced Lipid Peroxidation, Migration, Tube Formation, and Dysfunction of Human Aortic Endothelial Cells

Although aspalatone (acetylsalicylic acid maltol ester) is recognized as an antithrombotic agent with antioxidative and antiplatelet potential; its efficacy in preventing endothelial dysfunction is not known. In this study, we examined the antiangiogenic, antioxidative, and anti-inflammatory effect of aspalatone in human aortic endothelial cells (HAECs). Specifically, the effect of aspalatone on VEGF-induced HAECs growth, migration, tube formation, and levels of lipid peroxidation-derived malondialdehyde (MDA) was examined. Our results indicate that the treatment of HAECs with aspalatone decreased VEGF-induced cell migration, tube formation, and levels of MDA. Aspalatone also inhibited VEGF-induced decrease in the expression of eNOS and increase in the expression of iNOS, ICAM-1, and VCAM-1. Aspalatone also prevented the VEGF-induced adhesion of monocytes to endothelial cells. Furthermore, aspalatone also prevented VEGF-induced release of inflammatory markers such as Angiopoietin-2, Leptin, EGF, G-CSF, HB-EGF, and HGF in HAECs. Thus, our results suggest that aspalatone could be used to prevent endothelial dysfunction, an important process in the pathophysiology of cardiovascular diseases.

Abnormal Habituation of ‘nociceptive’ Blink Reflex in Migraine-Evidence for Increased Excitability of Trigeminal Nociception

We studied the habituation of the ‘nociceptive’ blink reflex (nBR) in 15 healthy subjects and 17 migraine patients interictally as well as during unilateral migraine headache within six hours of onset and after treatment. In healthy volunteers the mean regression coefficient (MRC) was – 3.9 following right sided and – 4.9 left sided stimulation. This equals an amplitude loss of 19.5% (5 X −3.9) and 24.5% (5 X −4.9), respectively, across five consecutive sweeps. An augmentation of nBR responses was found in migraine patients interictally: MRC = 3.3 following stimulation of the headache side (HA) and MRC = 4.0 of the non-headache side (non-HA). The differences were statistically significant (ANOVA: d.f. = 1, F = 25.8, P < 0.001). During the migraine attack MRCs were negative both before (−5.0, HA and – 4.0, non-HA) and after treatment (−2.6, HA and −1.9 non-HA) and significantly differed from those outside the migraine attack (ANOVA: d.f. = 2, F = 12.4, P < 0.001). The demonstrated lack of habituation of the nBR responses indicates an abnormal trigeminal nociceptive processing in migraine patients outside the migraine attack.

Nitroglycerin-Induced nNOS Increase in Rat Trigeminal Nucleus Caudalis is Inhibited by Systemic Administration of Lysine Acetylsalicylate but not of Sumatriptan

Systemic administration of nitroglycerin (NTG), a nitric oxide (NO) donor, in migraineurs triggers after several hours an attack of which the precise mechanisms are unknown. We found previously in rats that nitroglycerin (10 mg/kg s.c.) is able to increase significantly after 4 h the number of neuronal nitric oxide synthase (nNOS)-immunoreactive neurones in the cervical part of trigeminal nucleus caudalis. In the present experiments, we demonstrate that the 5-HT1B/D agonist sumatriptan (0.6 mg/kg s.c.) does not alter this phenomenon when given before NTG. By contrast, pretreatment with lysine acetylsalicylate (50 mg/kg i.m.) attenuates the NTG-induced nNOS expression in the superficial laminae of trigeminal nucleus caudalis. These findings suggest that effect of NTG on nNOS at a high dosage may involve the cycloxygenase pathway and that activation of the peripheral 5-HT1B/D receptors is not able to modify this effect. These data could help to better understand the role of NO in the pathogenesis of headaches and the action of antimigraine drugs.

[Pharmacological therapy of age-related macular degeneration based on etiopathogenesis]

It is of great therapeutic significance that disordered function of the vascular endothelium which supply the affected ocular structures plays a major role in the pathogenesis and development of age-related macular degeneration. Chronic inflammation is closely linked to diseases associated with endothelial dysfunction, and age-related macular degeneration is accompanied by a general inflammatory response. According to current concept, age-related macular degeneration is a local manifestation of systemic vascular disease. This recognition could have therapeutic implications because restoration of endothelial dysfunction can restabilize the condition of chronic vascular disease including age-related macular degeneration as well. Restoration of endothelial dysfunction by pharmaacological or non pharmacological interventions may prevent the development or improve endothelial dysfunction, which result in prevention or improvement of age related macular degeneration as well. Medicines including inhibitors of the renin-angiotensin system (converting enzyme inhibitors, angiotensin-receptor blockers and renin inhibitors), statins, acetylsalicylic acid, trimetazidin, third generation beta-blockers, peroxisome proliferator-activated receptor gamma agonists, folate, vitamin D, melatonin, advanced glycation end-product crosslink breaker alagebrium, endothelin-receptor antagonist bosentan, coenzyme Q10; "causal" antioxidant vitamins, N-acetyl-cysteine, resveratrol, L-arginine, serotonin receptor agonists, tumor necrosis factor-alpha blockers, specific inhibitor of the complement alternative pathway, curcumin and doxycyclin all have beneficial effects on endothelial dysfunction. Restoration of endothelial dysfunction can restabilize chronic vascular disease including age-related macular degeneration as well. Considering that the human vascular system is consubstantial, medicines listed above should be given to patients (1) who have no macular degeneration but have risk factors for the disease and are older than 50 years; (2) who have been diagnosed with unilateral age-related macular degeneration in order to prevent damage of the contralateral eye; (3) who have bilateral age-related macular degeneration in order to avert deterioration and in the hope of a potential improvement. However, randomised prospective clinical trials are still needed to elucidate the potential role of these drug treatments in the prevention and treatment of age-related macular degeneration.

Human GAPDH Is a Target of Aspirin's Primary Metabolite Salicylic Acid and Its Derivatives

The plant hormone salicylic acid (SA) controls several physiological processes and is a key regulator of multiple levels of plant immunity. To decipher the mechanisms through which SA’s multiple physiological effects are mediated, particularly in immunity, two high-throughput screens were developed to identify SA-binding proteins (SABPs). Glyceraldehyde 3-Phosphate Dehydrogenase (GAPDH) from plants (Arabidopsis thaliana) was identified in these screens. Similar screens and subsequent analyses using SA analogs, in conjunction with either a photoaffinity labeling technique or surface plasmon resonance-based technology, established that human GAPDH (HsGAPDH) also binds SA. In addition to its central role in glycolysis, HsGAPDH participates in several pathological processes, including viral replication and neuronal cell death. The anti-Parkinson’s drug deprenyl has been shown to suppress nuclear translocation of HsGAPDH, an early step in cell death and the resulting cell death induced by the DNA alkylating agent N-methyl-N’-nitro-N-nitrosoguanidine. Here, we demonstrate that SA, which is the primary metabolite of aspirin (acetyl SA) and is likely responsible for many of its pharmacological effects, also suppresses nuclear translocation of HsGAPDH and cell death. Analysis of two synthetic SA derivatives and two classes of compounds from the Chinese medicinal herb Glycyrrhiza foetida (licorice), glycyrrhizin and the SA-derivatives amorfrutins, revealed that they not only appear to bind HsGAPDH more tightly than SA, but also exhibit a greater ability to suppress translocation of HsGAPDH to the nucleus and cell death.

Superiority of zinc complex of acetylsalicylic acid to acetylsalicylic acid in preventing postischemic myocardial dysfunction

The pathophysiology of ischemic myocardial injury involves cellular events, reactive oxygen species, and an inflammatory reaction cascade. The zinc complex of acetylsalicylic acid (Zn(ASA)2) has been found to possess higher anti-inflammatory and lower ulcerogenic activities than acetylsalicylic acid (ASA). Herein, we studied the effects of both ASA and Zn(ASA)2 against acute myocardial ischemia. Rats were pretreated with ASA (75 mg/kg) or Zn(ASA)2 (100 mg/kg) orally for five consecutive days. Isoproterenol (85 mg/kg, subcutaneously [s.c.]) was applied to produce myocardial infarction. After 17-22 h, animals were anesthetized with sodium pentobarbital (60 mg/kg, intraperitoneally [i.p.]) and both electrical and mechanical parameters of cardiac function were evaluated in vivo. Myocardial histological and gene expression analyses were performed. In isoproterenol-treated rats, Zn(ASA)2 treatment normalized significantly impaired left-ventricular contractility index (Emax 2.6 ± 0.7 mmHg/µL vs. 4.6 ± 0.5 mmHg/µL, P < 0.05), increased stroke volume (30 ± 3 µL vs. 50 ± 6 µL, P < 0.05), decreased systemic vascular resistance (7.2 ± 0.7 mmHg/min/mL vs. 4.2 ± 0.5 mmHg/min/mL, P < 0.05) and reduced inflammatory infiltrate into the myocardial tissues. ECG revealed a restoration of elevated ST-segment (0.21 ± 0.03 mV vs. 0.09 ± 0.02 mV, P < 0.05) and prolonged QT-interval (79.2 ± 3.2 ms vs. 69.5 ± 2.5 ms, P < 0.05) by Zn(ASA)2. ASA treatment did not result in an improvement of these parameters. Additionally, Zn(ASA)2 significantly increased the mRNA-expression of superoxide dismutase 1 (+73 ± 15%), glutathione peroxidase 4 (+44 ± 12%), and transforming growth factor (TGF)-β1 (+102 ± 22%). In conclusion, our data demonstrate that oral administration of zinc and ASA in the form of bis(aspirinato)zinc(II) complex is superior to ASA in preventing electrical, mechanical, and histological changes after acute myocardial ischemia. The induction of antioxidant enzymes and the anti-inflammatory cytokine TGF-β1 may play a pivotal role in the mechanism of action of Zn(ASA)2.

Preventive Effect of Aspirin Eugenol Ester on Thrombosis in κ-Carrageenan-Induced Rat Tail Thrombosis Model

Based on the prodrug principle, aspirin eugenol ester (AEE) was synthesized, which can reduce the side effects of aspirin and eugenol. As a good candidate for new antithrombotic and anti-inflammatory medicine, it is essential to evaluate its preventive effect on thrombosis. Preventive effect of AEE was investigated in κ-carrageenan-induced rat tail thrombosis model. AEE suspension liquids were prepared in 0.5% sodium carboxymethyl cellulose (CMC-Na). AEE was administrated at the dosage of 18, 36 and 72 mg/kg. Aspirin (20 mg/kg), eugenol (18 mg/kg) and 0.5% CMC-Na (30 mg/kg) were used as control drug. In order to compare the effects between AEE and its precursor, integration of aspirin and eugenol group (molar ratio 1:1) was also designed in the experiment. After drugs were administrated intragastrically for seven days, each rat was injected intraperitoneally with 20 mg/kg BW κ-carrageen dissolved in physiological saline to induce thrombosis. The length of tail-thrombosis was measured at 24 and 48 hours. The blank group just was given physiological saline for seven days without κ-carrageenan administrated. The results indicated that AEE significantly not only reduced the average length of thrombus, PT values and FIB concentration, but also reduced the red blood cell (RBC), hemoglobin (HGB), hematocrit (HCT) and platelet (PLT). The effects of AEE on platelet aggregation and anticoagulant in vitro showed that AEE could inhibit adenosine diphosphate (ADP)-induced platelet aggregation as dose-dependence but no notable effect on blood clotting. From these results, it was concluded that AEE possessed positive effect on thrombosis prevention in vivo through the reduction of FIB, PLT, inhibition of platelet aggregation and the change of TT and PT values.

The effects of aspirin, flurbiprofen, and NO-donating acetylsalicylic acid (NCX 4016) on mice models of endotoxic and septic shock

BACKGROUND/AIM

Nitric oxide-donating nonsteroidal antiinflammatory drugs (NO-NSAIDs) are a promising new class of antiinflammatory agents, which are obtained by adding NO-donating moieties to the existing conventional NSAID molecules. The aim of this study was to investigate the effects of aspirin, flurbiprofen, and NO-donating acetylsalicylic acid (NCX 4016) on cecal ligation and puncture (CLP) and endotoxin-induced septic shock (LPS) models in mice.

MATERIALS AND METHODS

Overall survival and spleen and liver weights were monitored in LPS and CLP models. Histopathological examinations of liver and spleen were performed at the end of the experimental protocols.

RESULTS

NCX 4016 was able to reverse the increased spleen weight in CLP-operated animals, whereas aspirin or flurbiprofen did not. Similar to the results of the CLP model, none of the drugs modified the survival rates in the LPS model. Flurbiprofen in particular produced significant histopathological damage in spleens and livers, which was less significant with aspirin. NCX 4016 did not cause any liver damage.

CONCLUSION

NCX 4016 has the potential to be used in septic states, while special attention has to be paid to the effects of aspirin and flurbiprofen on the liver and spleen.

Phospho-NSAIDs have enhanced efficacy in mice lacking plasma carboxylesterase: implications for their clinical pharmacology

PURPOSE

The purpose of the study was to evaluate the metabolism, pharmacokinetics and efficacy of phospho-NSAIDs in Ces1c-knockout mice.

METHODS

Hydrolysis of phospho-NSAIDs by Ces1c was investigated using Ces1c-overexpressing cells. The rate of phospho-NSAID hydrolysis was compared between wild-type, Ces1c+/- and Ces1c-/- mouse plasma in vitro, and the effect of plasma Ces1c on the cytotoxicity of phospho-NSAIDs was evaluated. Pharmacokinetics of phospho-sulindac was examined in wild-type and Ces1c-/- mice. The impact of Ces1c on the efficacy of phospho-sulindac was investigated using lung and pancreatic cancer models in vivo.

RESULTS

Phospho-NSAIDs were extensively hydrolyzed in Ces1c-overexpressing cells. Phospho-NSAID hydrolysis in wild-type mouse plasma was 6-530-fold higher than that in the plasma of Ces1c-/- mice. Ces1c-expressing wild-type mouse serum attenuated the in vitro cytotoxicity of phospho-NSAIDs towards cancer cells. Pharmacokinetic studies of phospho-sulindac using wild-type and Ces1c-/- mice demonstrated 2-fold less inactivation of phospho-sulindac in the latter. Phospho-sulindac was 2-fold more efficacious in inhibiting the growth of lung and pancreatic carcinoma in Ces1c -/- mice, as compared to wild-type mice.

CONCLUSIONS

Our results indicate that intact phospho-NSAIDs are the pharmacologically active entities and phospho-NSAIDs are expected to be more efficacious in humans than in rodents due to their differential expression of carboxylesterases.

Phospho-aspirin-2 (MDC-22) inhibits estrogen receptor positive breast cancer growth both in vitro and in vivo by a redox-dependent effect

Phospho-aspirin (PA-2) is a novel aspirin derivative that exhibits promising anticancer properties and is considerably safer than conventional aspirin. In this study, we investigated the chemotherapeutic efficacy of PA-2 in preclinical models of estrogen receptor positive (ER+) breast cancer and elucidated its mechanism of action. PA-2 inhibited the growth of ER+ cells more potently than aspirin in vitro, and exerted a triple cytokinetic effect that includes induction of apoptosis and cell cycle arrest as well as the inhibition of cell proliferation. PA-2 is highly efficacious in vivo, as treatment of established MCF7 xenografts with PA-2 induced tumor stasis (98.2% inhibition, p<0.01). PA-2 triggered the activation of p53-dependent apoptosis via two distinct mechanisms: 1) acetylation of p53 (at K373), which disrupts its interaction with its transcription repressor MDM2, and 2) translocation of p53 to the mitochondria leading to the dissipation of mitochondrial transmembrane potential (ΔΨ_m). Consistent with these observations, both the RNAi-mediated knockdown of p53 and forced deactylation via HDAC1 over-expression attenuated the anticancer effect of PA-2 in MCF7 cells. An upstream mediator of the signaling effects of PA-2 is RONS. PA-2 induced oxidative stress in vitro and in mice bearing MCF7 xenografts; its induction effect appears to be tumor-specific. Crucially, administration of N-acetylcysteine, a ROS scavenger, abrogated the effect of PA-2 on p53 acetylation and mitochondria translocation, thus identifying RONS as proximal molecules mediating the anticancer effect of PA-2. In summary, our findings demonstrate that PA-2 is a promising antineoplastic compound against ER+ breast cancer, warranting further evaluation as an anticancer agent.

Hydrogen sulfide releasing aspirin, ACS14, attenuates high glucose-induced increased methylglyoxal and oxidative stress in cultured vascular smooth muscle cells

Hydrogen sulfide is a gasotransmitter with vasodilatory and anti-inflammatory properties. Aspirin is an irreversible cyclooxygenase inhibitor anti-inflammatory drug. ACS14 is a novel synthetic hydrogen sulfide releasing aspirin which inhibits cyclooxygenase and has antioxidant effects. Methylglyoxal is a chemically active metabolite of glucose and fructose, and a major precursor of advanced glycation end products formation. Methylglyoxal is harmful when produced in excess. Plasma methylglyoxal levels are significantly elevated in diabetic patients. Our aim was to investigate the effects of ACS14 on methylglyoxal levels in cultured rat aortic vascular smooth muscle cells. We used cultured rat aortic vascular smooth muscle cells for the study. Methylglyoxal was measured by HPLC after derivatization, and nitrite+nitrate with an assay kit. Western blotting was used to determine NADPH oxidase 4 (NOX4) and inducible nitric oxide synthase (iNOS) protein expression. Dicholorofluorescein assay was used to measure oxidative stress. ACS14 significantly attenuated elevation of intracellular methylglyoxal levels caused by incubating cultured vascular smooth muscle cells with methylglyoxal (30 µM) and high glucose (25 mM). ACS14, but not aspirin, caused a significant attenuation of increase in nitrite+nitrate levels caused by methylglyoxal or high glucose. ACS14, aspirin, and sodium hydrogen sulfide (NaHS, a hydrogen sulfide donor), all attenuated the increase in oxidative stress caused by methylglyoxal and high glucose in cultured cells. ACS14 prevented the increase in NOX4 expression caused by incubating the cultured VSMCs with MG (30 µM). ACS14, aspirin and NaHS attenuated the increase in iNOS expression caused by high glucose (25 mM). In conclusion, ACS14 has the novel ability to attenuate an increase in methylglyoxal levels which in turn can reduce oxidative stress, decrease the formation of advanced glycation end products and prevent many of the known deleterious effects of elevated methylglyoxal. Thus, ACS14 has the potential to be especially beneficial for diabetic patients pending further in vivo studies.

Preparation and characterization of a novel aspirin derivative with anti-thrombotic and gastric mucosal protection properties

The use of acetylsalicylic acid (ASP) is limited by its adverse effects, especially the effect on the gastric mucosa. To address this problem, we synthesized a derivative form of ASP, prepared by modification of ASP with nano-hydroxyapatite (a kind of inorganic particle containing Ca(2+)). The derivative was named Ca-ASP. Structural study showed that Ca-ASP was a kind of carboxylate containing intramolecular hydrogen bonds. Rats given a high dose of Ca-ASP (5 mmol per kg body weight) showed similar anti-thrombotic activity as those given the same dose of ASP, but had much lower gastric mucosal damage than ASP (UI: 2 versus UI: 12.5). These rats also showed reduced expression of COX-2, but their COX-1 expression was similar to that of control rats, but significantly higher than that of ASP-administered rats. Furthermore, the level of prostaglandin E2 (PGE2) was up-regulated in Ca-ASP-administered rats compared to ASP-administered rats. Taken together, the results showed that Ca-ASP possessed similar antithrombotic activity as ASP but without the side effect associated with ASP, and the underlying mechanism may center on inhibiting COX-2 without inhibiting COX-1, and thus favouring the production of PGE2, the prostaglandin that plays a vital role in the suppression of platelet aggregation and thrombosis, as well as in the repair of gastric damage.

Lysine acetylsalicylate increases the safety of a paraquat formulation to freshwater primary producers: a case study with the microalga Chlorella vulgaris

Large amounts of herbicides are presently used in the industrialized nations worldwide, with an inexorable burden to the environment, especially to aquatic ecosystems. Primary producers such as microalgae are of especial concern because they are vital for the input of energy into the ecosystem and for the maintenance of oxygen in water on which most of other marine life forms depend on. The herbicide paraquat (PQ) is known to cause inhibition of photosynthesis and irreversible damage to photosynthetic organisms through generation of reactive oxygen species in a light-dependent manner. Previous studies have led to the development of a new formulation of PQ containing lysine acetylsalicylate (LAS) as an antidote, which was shown to prevent the mammalian toxicity of PQ, while maintaining the herbicidal effect. However, the safety of this formulation to primary producers in relation to commercially available PQ formulations has hitherto not been established. Therefore, the aim of this study was to evaluate the toxicity of the PQ+LAS formulation in comparison with the PQ, using Chlorella vulgaris as a test organism. Effect criterion was the inhibition of microalgal population growth. Following a 96 h exposure to increasing concentrations of PQ, C. vulgaris growth was almost completely inhibited, an effect that was significantly prevented by LAS at the proportion used in the formulation (PQ+LAS) 1:2 (mol/mol), while the highest protection was achieved at the proportion of 1:8. In conclusion, the present work demonstrated that the new formulation with PQ+LAS has a reduced toxicity to C. vulgaris when compared to Gramoxone(®).

[A new technology for evaluating pharmacodynamics of antiaggregants]

The effect of antiaggregants on the system of regulation of the aggregative state of the whole blood in healthy volunteers has been studied using the global test of low-frequency piezothrombelastography. It is established that specific effects of antiaggregants are manifested in all stages of fibrinogenesis (initiation/amplification and propagation). According to the results of the global test at initial stages of hemocoagulation (initiation/amplification), a pronounced specific antiaggregative effect of COX-1 blockers and ADP receptors is accompanied by the intensification of thrombin activity and the formation of chronometric hypercoagulation. The blocker of phosphodiesterase, while losing a specific antiaggregative effect, has a lower influence on the change of thrombin activity, thus ensuring hronometric and structural hypocoagulation at the subsequent stages of fibrinogenesis. The proposed method can be used for real-time monitoring of the results of pharmacotherapy and drug effects at various stages of fibrinogenesis in the program of personalized antiaggregant therapy.

[Primary angioplasty in a patient with acute inferior myocardial infarction: the unexpected trap]

We report a case of acute inferior myocardial infarction caused by occlusion of an anomalous right coronary artery, successfully treated with primary angioplasty. When an anomalous origin of a coronary artery is suspected, it is crucial to perform aortic angiography or left ventriculography in multiple projections.

New formulation of paraquat with lysine acetylsalicylate with low mammalian toxicity and effective herbicidal activity

BACKGROUND

Currently, the commercial formulations of the herbicide paraquat are highly toxic to humans, and no effective antidote is available for paraquat poisoning. The aim of the present study was to develop a safe formulation, combining paraquat and the known antidote lysine acetylsalicylate. The toxicity of a mixture of Gramoxone® (20% paraquat) and lysine acetylsalicylate in adult Wistar male rats and the herbicidal efficacy against grass lawn (50% of Poa pratensis and 50% of Festuca arundinacea) were evaluated. This new formulation was administered to Wistar rats by gavage at 125 mg kg(-1) of paraquat ion and lysine acetylsalicylate at 79, 158 or 316 mg kg(-1) body weight, and the survival rate was observed for 30 days.

RESULTS

The survival rate of the paraquat group was only 40%, while lysine acetylsalicylate provided effective protection, with full survival observed in the groups that received 125 mg kg(-1) of paraquat ion and 316 mg kg(-1) of lysine acetylsalicylate. Both formulations of paraquat, either in the absence or in the presence of lysine acetylsalicylate, provided the same herbicidal activity against the tested herbal species.

CONCLUSIONS

The present formulation of paraquat containing lysine acetylsalicylate, significantly decreases mammalian toxicity while maintaining effective herbicidal activity.

High glucose inhibits the aspirin-induced activation of the nitric oxide/cGMP/cGMP-dependent protein kinase pathway and does not affect the aspirin-induced inhibition of thromboxane synthesis in human platelets

Since hyperglycemia is involved in the "aspirin resistance" occurring in diabetes, we aimed at evaluating whether high glucose interferes with the aspirin-induced inhibition of thromboxane synthesis and/or activation of the nitric oxide (NO)/cGMP/cGMP-dependent protein kinase (PKG) pathway in platelets. For this purpose, in platelets from 60 healthy volunteers incubated for 60 min with 5-25 mmol/L d-glucose or iso-osmolar mannitol, we evaluated the influence of a 30-min incubation with lysine acetylsalicylate (L-ASA; 1-300 μmol/L) on 1) platelet function under shear stress; 2) aggregation induced by sodium arachidonate or ADP; 3) agonist-induced thromboxane production; and 4) NO production, cGMP synthesis, and PKG-induced vasodilator-stimulated phosphoprotein phosphorylation. Experiments were repeated in the presence of the antioxidant agent amifostine. We observed that platelet exposure to 25 mmol/L d-glucose, but not to iso-osmolar mannitol, 1) reduced the ability of L-ASA to inhibit platelet responses to agonists; 2) did not modify the L-ASA-induced inhibition of thromboxane synthesis; and 3) prevented the L-ASA-induced activation of the NO/cGMP/PKG pathway. Preincubation with amifostine reversed the high-glucose effects. Thus, high glucose acutely reduces the antiaggregating effect of aspirin, does not modify the aspirin-induced inhibition of thromboxane synthesis, and inhibits the aspirin-induced activation of the NO/cGMP/PKG pathway. These results identify a mechanism by which high glucose interferes with the aspirin action.

Differential inhibition of tumour cell-induced platelet aggregation by the nicotinate aspirin prodrug (ST0702) and aspirin

BACKGROUND AND PURPOSE

Tumour cell-induced platelet aggregation (TCIPA) facilitates cancer cell invasion, angiogenesis and the formation of metastatic foci. TCIPA can be modulated by pharmacological inhibitors of MMP-2 and ADP; however, the COX inhibitor aspirin did not prevent TCIPA. In this study, we have tested the pharmacological effects of a new group of isosorbide-based aspirin prodrugs on TCIPA.

EXPERIMENTAL APPROACH

TCIPA was induced in human platelets by mixing with human adenocarcinoma or fibrosarcoma cells under no flow and flow conditions. The release of gelatinases and P-selectin expression during TCIPA were studied by zymography and flow cytometry respectively.

KEY RESULTS

Tumour cells caused platelet aggregation. This aggregation resulted in the release of MMP-2 and a significant up-regulation of P-selectin on platelets, indicative of platelet activation. Pharmacological modulation of TCIPA revealed that ST0702, one of the aspirin prodrugs, down-regulated TCIPA while aspirin was ineffective. The deacetylated metabolite of ST0702, 5-nicotinate salicylate (ST0702 salicylate), down-regulated both ADP-stimulated platelet aggregation and TCIPA.

CONCLUSIONS AND IMPLICATIONS

Our results show that ST0702 was an effective inhibitor of TCIPA in vitro. Its deacetylated metabolite may contribute to the effects of ST0702 by inhibiting ADP-mediated TCIPA.

H(2)S-releasing aspirin protects against aspirin-induced gastric injury via reducing oxidative stress

The aim of this study was to examine the effect of ACS14, a hydrogen sulfide (H(2)S)-releasing derivative of aspirin (Asp), on Asp-induced gastric injury. Gastric hemorrhagic lesions were induced by intragastric administration of Asp (200 mg/kg, suspended in 0.5% carboxymethyl cellulose solutions) in a volume of 1 ml/100 g body weight. ACS14 (1, 5 or 10 mg/kg) was given 30 min before the Asp administration. The total area of gastric erosions, H(2)S concentration and oxidative stress in gastric tissues were measured three hours after administration of Asp. Treatment with Asp (200 mg/kg), but not ACS14 (430 mg/kg, at equimolar doses to 200 mg/kg Asp), for 3 h significantly increased gastric mucosal injury. The damage caused by Asp was reversed by ACS14 at 1-10 mg/kg in a concentration-dependent manner. ACS14 abrogated Asp-induced upregulation of COX-2 expression, but had no effect on the reduced PGE(2) level. ACS14 reversed the decreased H(2)S concentrations and blood flow in the gastric tissue in Asp-treated rats. Moreover, ACS14 attenuated Asp-suppressed superoxide dismutase-1 (SOD-1) expression and GSH activity, suggesting that ACS14 may stimulate antioxidants in the gastric tissue. ACS14 also obviously inhibited Asp-induced upregulation of protein expression of oxidases including XOD, p47(phox) and p67(phox). In conclusion, ACS14 protects Asp induced gastric mucosal injury by inhibiting oxidative stress in the gastric tissue.

Effect on walking distance and atherosclerosis progression of a nitric oxide-donating agent in intermittent claudication

BACKGROUND

Peripheral arterial disease (PAD) is almost invariably associated with a generalized atherosclerotic involvement of the arterial tree and endothelial dysfunction. Previous short-term studies showed improvement of vascular reactivity and walking capacity in PAD patients by measures aimed at restoring nitric oxide (NO) production. NO is also known to prevent the progression of atherosclerosis. We wished to assess whether the prolonged administration of an NO-donating agent (NCX 4016) improves the functional capacity of PAD patients and affects the progression of atherosclerosis as assessed by carotid intima-media thickness (IMT).

METHODS

This prospective, double-blind, placebo-controlled study enrolled 442 patients with stable intermittent claudication who were randomized to NCX 4016 (800 mg, twice daily) or its placebo for 6 months. The primary study outcome was the absolute claudication distance on a constant treadmill test (10% incline, 3 km/h). The main secondary end point was the change of the mean far-wall right common carotid artery IMT.

RESULTS

The increase of absolute claudication distance at 6 months compared with baseline was 126±140 meters in the placebo-treated group and 117±137 meters in the NCX 4016-treated group, with no significant differences. Carotid IMT increased in the placebo-treated group (+0.01±0.01 mm; P=.55) and decreased in the NCX 4016-treated group (-0.03±0.01 mm; P=.0306). Other secondary end points did not differ between the two treatments.

CONCLUSIONS

Long-term NO donation does not improve the claudication distance but does reduce progression of atherosclerosis in patients with PAD. Further studies aimed at assessing whether long-term NO donation may prevent ischemic cardiovascular events are warranted.

NOSH-aspirin (NBS-1120), a novel nitric oxide- and hydrogen sulfide-releasing hybrid is a potent inhibitor of colon cancer cell growth in vitro and in a xenograft mouse model

Nonsteroidal anti-inflammatory drugs (NSAIDs) are prototypical anti-cancer agents. However, their long-term use is associated with adverse gastrointestinal effects. Recognition that endogenous gaseous mediators, nitric oxide (NO) and hydrogen sulfide (H(2)S) can increase mucosal defense mechanisms has led to the development of NO- and H(2)S-releasing NSAIDs with increased safety profiles. Here we report on a new hybrid, NOSH-aspirin, which is an NO- and H(2)S-releasing agent. NOSH-aspirin inhibited HT-29 colon cancer growth with IC(50)s of 45.5 ± 2.5, 19.7 ± 3.3, and 7.7 ± 2.2 nM at 24, 48, and 72 h, respectively. This is the first NSAID based agent with such high degree of potency. NOSH-aspirin inhibited cell proliferation, induced apoptosis, and caused G(0)/G(1) cell cycle block. Reconstitution and structure-activity studies representing a fairly close approximation to the intact molecule showed that NOSH-aspirin was 9000-fold more potent than the sum of its parts towards growth inhibition. NOSH-aspirin inhibited ovine COX-1 more than ovine COX-2. NOSH-ASA treatment of mice bearing a human colon cancer xenograft caused a reduction in volume of 85%. Taken together, these results demonstrate that NOSH-aspirin has strong anti-cancer potential and merits further evaluation.

[A young man with recurrent chest pain]

BACKGROUND

Pericarditis is seen quite often in daily clinical practice. It is a condition that is fairly easy to diagnose, but which frequently recurs.

CASE DESCRIPTION

A 23-year-old man suffered from recurring episodes of chest pain which, following further investigation, appeared to be a result of pericarditis. MRI revealed indications for acute exacerbation of chronic pericarditis. Additional investigation showed no underlying cause for the pericarditis. After long-term medication with calcium carbasalate and colchicine there was no recurrence and the patient was able to function as before.

CONCLUSION

Chest pain in young people can be a symptom of pericarditis. This condition quite often recurs, but in most patients no underlying cause is revealed. Adequate medication with calcium carbasalate and colchicine reduces the chance of recurrence.

Hydrogen sulfide-releasing NSAIDs inhibit the growth of human cancer cells: a general property and evidence of a tissue type-independent effect

Hydrogen sulfide-releasing non-steroidal anti-inflammatory drugs (HS-NSAIDs) are an emerging novel class of compounds with significant anti-inflammatory properties. They consist of a traditional NSAID to which an H(2)S-releasing moiety is covalently attached. We examined the effects of four different HS-NSAIDs on the growth properties of eleven different human cancer cell lines of six different tissue origins. Human colon, breast, pancreatic, prostate, lung, and leukemia cancer cell lines were treated with HS-aspirin, -sulindac, -iburofen, -naproxen, and their traditional counterparts. HS-NSAIDs inhibited the growth of all cancer cell lines studied, with potencies of 28- to >3000-fold greater than that of their traditional counterparts. HS-aspirin (HS-ASA) was consistently the most potent. HS-NSAIDs inhibited cell proliferation, induced apoptosis, and caused G(0)/G(1) cell cycle block. Metabolism of HS-ASA by colon cells showed that the acetyl group of ASA was hydrolyzed rapidly, followed by hydrolysis of the ester bond linking the salicylate anion to the H(2)S releasing moiety, producing salicylic acid and ADT-OH from which H(2)S is released. In reconstitution studies, ASA and ADT-OH were individually less active than the intact HS-ASA towards cell growth inhibition. Additionally, the combination of these two components representing a fairly close approximation to the intact HS-ASA, was 95-fold less active than the intact HS-ASA for growth inhibition. Taken together, these results demonstrate that HS-NSAIDs have potential anti-growth activity against a wide variety of human cancer cells.

Lysine acetylsalicylate ameliorates lung injury in rats acutely exposed to paraquat

BACKGROUND

Paraquat (PQ), an effective and widely used herbicide, has been proven to be safe when appropriately applied to eliminate weeds. However, PQ poisoning is an extremely frustrating clinical condition with a high mortality and with a lack of effective treatments in humans. PQ mainly accumulates in the lung, and the main molecular mechanism of PQ toxicity is based on redox cycling and intracellular oxidative stress generation. The aim of this study was to evaluate whether lysine acetylsalicylate (LAS) could protect the lung from the damage of PQ poisoning and to study the mechanisms of protection.

METHODS

A model of PQ poisoning was established in 75 Sprague-Dawley rats by intragastric administration of 50 mg/kg PQ, followed by treatment with 200 mg/kg of LAS. The rats were randomly divided into sham, PQ, and PQ + LAS groups, with 25 in each group. We assessed and compared the malonaldehyde (MDA) content, superoxide dismutase activity (SOD), glutathion peroxidase (GSH-Px), and catalase (CAT) in serum and lung and the hydroxyproline (HYP) content, pathological changes, apoptosis and expression of Bcl-2/Bax protein in lung of rats on days 1, 3, 7, 14 and 21 after PQ poisoning and LAS treatment.

RESULTS

Compared to the PQ group rats, early treatment with LAS reduced the MDA and HYP contents, and increased the SOD, GSH-Px, and CAT activities in the serum and lung on days 1, 3, 7, 14, and 21 after PQ poisoning (all P < 0.05). After early LAS treatment, the apoptotic rate and Bax expression of lung decreased, the Bcl-2 expression increased, and the Bcl-2/Bax ratio increased, compared to the PQ group rats. Furthermore, the pathological results of lungs revealed that after LAS treatment, early manifestations of PQ poisoning, such as hemorrhage, edema and inflammatory-cell infiltration, were improved to some degree, and collagen fibers in the pulmonary interstitium were also obviously reduced.

CONCLUSION

In this rat model of PQ poisoning, LAS effectively ameliorated the lung injury induced by PQ, possibly through antioxidation, anti-fibrosis, anti-apoptosis, and anticoagulation.

Rapid desensitisation of patients with aspirin allergy who undergo coronary angioplasty

INTRODUCTION

Although aspirin is the cornerstone of medication in patients with coronary artery disease, a minority of these patients have aspirin sensitivity. The aim of this study was to evaluate the efficacy and safety of an aspirin desensitisation protocol in patients scheduled for coronary angioplasty and stenting.

METHODS

We used a challenge-desensitisation protocol in 11 patients (6 men, mean age 56 ± 9.6 years) who reported allergy to aspirin and were to undergo percutaneous coronary intervention with stent implantation. Eight had a history of cutaneous sensitivity, 1 had rhinitis, 1 reported urticaria and rhinitis, while another patient showed a respiratory response in the form of an asthma attack after taking aspirin in the past. Eight successive doses of aspirin were given (0.1, 0.3, 10, 30, 40, 81, 162, 325 mg) at intervals of 15-25 min over a total period of 2 h 15 min.

RESULTS

All patients with aspirin sensitivity completed the desensitisation therapy successfully, without adverse effects, and subsequently underwent angioplasty and stenting. During follow up, the patients continued to take aspirin over 6-19 months without any problems.

CONCLUSIONS

Rapid aspirin desensitisation is an effective and safe procedure for patients with aspirin allergy who are to undergo coronary angioplasty and stenting, allowing them to receive the optimum treatment.

Analgesic and Antipyretic Properties of Some Aspirin Derivatives

Several derivatives of acetylsalicylic acid have been tested for analgesic and antipyretic properties in mice and rats. o-Diphenylacetoxy benzoic acid (O-(diphenylacetyl)salicylic acid; DPA) is a superior analgesic but an inferior antipyretic to aspirin, DPA has a low toxicity: it failed to show significant anti-inflammatory or tranquillising properties. In dogs it produced only slight and transient falls in blood pressure and there was no appreciable effect on the direct or reflex muscle preparation.

The novel phospho-non-steroidal anti-inflammatory drugs, OXT-328, MDC-22 and MDC-917, inhibit adjuvant-induced arthritis in rats

BACKGROUND AND PURPOSE

The use of non-steroidal anti-inflammatory drugs (NSAIDs) in the treatment of rheumatoid arthritis (RA) is limited by their toxicity. We evaluated the anti-inflammatory efficacy and safety of three novel modified NSAIDs, phospho-aspirin, phospho-ibuprofen and phospho-sulindac.

EXPERIMENTAL APPROACH

We determined the anti-inflammatory effects and gastrointestinal safety of the phospho-NSAIDs in the rat adjuvant arthritis model and studied their mechanism of action in cultured cells, Cytokines were measured with elisa and activation of nuclear factor-κB (NF-κB) by immunohistochemistry.

KEY RESULTS

All three phospho-NSAIDs showed less gastrointestinal toxicity than their parent compounds and demonstrated strong anti-inflammatory effects, essentially reversing joint inflammation and oedema. They have a broad but not uniform effect on the expression of relevant cytokines, in general decreasing IL-6 and IL-1β and increasing IL-10 levels in rat plasma and cultured cells. Phospho-sulindac and phospho-ibuprofen but not phospho-aspirin suppressed PGE(2) production in vitro, whereas phospho-aspirin (in contrast to aspirin) showed the same effect in vivo. In joint tissues, phospho-aspirin inhibited NF-κB activation, and suppressed inflammation and bone resorption. Phospho-aspirin also inhibited Jurkat T cell proliferation. In general, phospho-aspirin had greater efficacy but different effects upon inflammatory mediators compared with aspirin. The chemical modification of the parent NSAIDs seems crucial for their safety and efficacy.

CONCLUSIONS AND IMPLICATIONS

Phospho-aspirin, phospho-ibuprofen and phospho-sulindac were safer than their parent NSAIDs, were highly effective in rat adjuvant arthritis and inhibited many key mediators in the pathophysiology of RA. These novel compounds are promising candidate drugs for the treatment of RA and merit further evaluation.

Nitric oxide (NO)-releasing aspirin exhibits a potent esophagoprotection in experimental model of acute reflux esophagitis. Role of nitric oxide and proinflammatory cytokines

The purpose of this study was to develop an acute animal model of reflux esophagitis, which would be suitable to induce the esophageal damage caused by gastric acid reflux, thus mimicking the esophageal injury of human gastroesophageal reflux disease (GERD). Global research indicates that GERD is rapidly increasing among the world's population. NSAIDs are known to induce gastrointestinal damage and low doses of aspirin (ASA) have been shown to increase the incidences of GERD in humans. Gastric acid and pepsin secretion and enhanced COX-2 expression were implicated in the pathogenesis of reflux esophagitis, but the effect of selective COX-2 inhibitors against lesions induced by the reflux of gastric acid content into esophagus has not been thoroughly studied. Here, we compared the effect of aspirin (ASA) and so called "safe" nitric oxide (NO) derivative of ASA with those of non-selective and selective cyclooxygenase (COX)-1 and COX-2 in rat model of reflux esophagitis. Reflux esophagitis was induced in anesthetized rats by ligating the pylorus and limiting ridge transitional region between the forestomach and the corpus of stomach. Subsequently, the total gastric reservoir to store gastric juice was greatly diminished, resulting in the reflux of this juice into the esophagus. Rats with esophagitis received intragastric (i.g.) pretreatment either with: 1) vehicle (saline), 2) ASA or NO-ASA (100 mg/kg); 3) the non-selective COX inhibitor, indomethacin (5 mg/kg); 4) the selective COX-1 inhibitor, SC-560 (10 mg/kg), and 5) the selective COX-2 inhibitor, celecoxib (5 mg/kg). In a separate series of rats with reflux oesophagitis, the efficacy of ASA combined with a donor of NO, glyceryl trinitrate (GTN; 10 mg/kg i.g.) to prevent esophageal mucosal injury was investigated. Four hours after induction of esophagitis the gross mucosal damage was graded with a macroscopic lesion index (LI) from 0-6. The esophageal blood flow (EBF) was determined by H₂-gas clearance technique, the oesophageal mucosal and blood samples were collected for histology and analysis of the RT-PCR expression and release of proinflammatory cytokines IL-1β, TNF-α and IL-6 using specific ELISA. The exposure of the esophagus to reflux of gastric acid time-dependently increased the esophageal LI and morphologic damage, and decreased EBF with the most significant changes observed at 4 hrs after the ligation procedure. The pretreatment with native ASA in the dose that suppressed the generation of mucosal PGE₂, enhanced gross and histologic esophageal damage and produced a significant fall in EBF. NO-ASA or ASA coupled with GTN counteracted the aggravation of the damage and accompanying fall in EBF when compared with native ASA applied alone to rats with esophagitis. The proinflammatory cytokines IL-1β and TNF-α were overexpressed in rats with esophagitis and those pretreated with ASA but this effect was significantly attenuated by NO-ASA. Plasma IL-1β, TNF-α and IL-6 were negligible in the intact rats but significantly increased in those with esophagitis, with this effect being further enhanced by non-selective (indomethacin) and selective (SC-560, celecoxib) COX-1 and COX-2 inhibitors. We conclude that conventional NSAID such as aspirin augments esophagitis, while NO-ASA exerts the beneficial protective effect against reflux esophagitis via the enhancement of esophageal microcirculation due to NO release and an inhibitory effect on expression and release of pro-inflammatory cytokines.

Vasoactive drugs for acute stroke

BACKGROUND

It is unclear whether blood pressure (BP) should be altered actively during the acute phase of stroke.

OBJECTIVES

To assess the effect of lowering or elevating BP in people with acute stroke, and the effect of different vasoactive drugs on BP in acute stroke.

SEARCH STRATEGY

We searched the Cochrane Stroke Group Trials Register (last searched June 2009), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4, 2009), MEDLINE (1966 to October 2009), EMBASE (1980 to October 2009), and Science Citation Index (1981 to October 2009).

SELECTION CRITERIA

Randomised trials of interventions that would be expected, on pharmacological grounds, to alter BP in patients within one week of the onset of acute stroke.

DATA COLLECTION AND ANALYSIS

Two review authors independently applied the trial inclusion criteria, assessed trial quality, and extracted data.

MAIN RESULTS

We identified 131 trials involving in excess of 18,000 patients; a further 13 trials are ongoing. We obtained data for 43 trials (7649 patients). Among BP-lowering trials, beta receptor antagonists lowered BP (early systolic BP (SBP) mean difference (MD) -6.1 mmHg, 95% CI -11.4 to -0.9; late SBP MD -4.9 mmHg, 95% CI -10.2 to 0.4; late diastolic BP (DBP) MD -4.5 mmHg, 95% CI -7.8 to -1.2). Oral calcium channel blockers (CCB) lowered BP (late SBP MD -3.2 mmHg, 95% CI -5.4 to -1.1; early DBP MD -2.5, 95% CI -5.6 to 0.7; late DBP MD -2.1, 95% CI -3.5 to -0.7). Nitric oxide donors lowered BP (early SBP MD -10.3 mmHg, 95% CI -17.6 to -3.0). Prostacyclin lowered BP (late SBP MD, -7.7 mmHg, 95% CI -15.6 to 0.2; late DBP MD -3.9 mmHg, 95% CI -8.1 to 0.4). Among BP-increasing trials, diaspirin cross-linked haemoglobin (DCLHb) increased BP (early SBP MD 15.3 mmHg, 95% CI 4.0 to 26.6; late SBP MD 15.9 mmHg, 95% CI 1.8 to 30.0). None of the drug classes significantly altered outcome apart from DCLHb which increased combined death or dependency (odds ratio (OR) 5.41, 95% CI 1.87 to 15.64).

AUTHORS' CONCLUSIONS

There is not enough evidence to evaluate reliably the effect of altering BP on outcome after acute stroke. However, treatment with DCLHb was associated with poor clinical outcomes. Beta receptor antagonists, CCBs, nitric oxide, and prostacyclin each lowered BP during the acute phase of stroke. In contrast, DCLHb increased BP.

[Ukrainian break-through in the European and world strategy of individual prophylaxis of ischemic stroke in patients with arterial hypertension]

To reduce of epidemic of an ischemic stroke often developed in patients with arterial hypertension, we have developed the program of individual diagnostics of a clinical risk factor and a method to optimize the treatment directed on prophylactic of cardio-vascular complications. The main predictor of blood clot formation, hypercoagulation, had been detected by means of our laboratory technology "Coaguloscop-TC" (Ukraine patent) which allows registration 36 biomarkers of coagulation cascade and the fibrinolysys system. It can calculate coagulation module (MC) and fibrinolysis module (MF). These biomarkers corresponded to new (2009) requirements of the American Heart Association. After analysis of results of 818 patients we have defined an interval line of MC and MF disorders located within degree (from I to X) of their dysfunction. Patients with hypertension (400) of II-III stage and concomitant ischemic heart disease (44.2% of cases) without antiplatelet therapies, hypercoagulation was found in 61% of patients. Very high risk factor (MC IX-X degree) took place in all patients with acute stroke. The high risk factor (MC VI-VIII degree) testified presence of urgent situation, for its correction we administered an antiplatelet agent (acelisin) intramuscularly once a day for 4-6 days in an individual dosis which was calculated based on MC level and body weight. After the treatment MC usually decreased to 2 degrees (low risk factor). The dislipidemia negatively effects efficiency of the treatment as its biomarkers have direct correlation (P < 0.001) with density of blood clot which increase inhibits the fibrinolysis system to dissolve blood clot. The use of effective complex treatment of patients with arterial hypertension ( antihypertensive, antiplatelet and hypolipidemic (statin) medications) is supposed to decrease the development of ischemic stroke by 80% that four times higher than in the 2006-2020 program assigned by Ministry of Health of Ukraine.

Modulation of thiol homeostasis induced by H2S-releasing aspirin

The H(2)S-releasing aspirin (ACS14) containing a dithiolethione moiety has been demonstrated to maintain the thromboxane-suppressing activity of the parent compound, but it seems to spare the gastric mucosa by affecting redox imbalance through increased H(2)S/glutathione (GSH) formation. Nevertheless, the mechanisms by which ACS14 is able to elevate the levels of these agents has not been fully elucidated so far. In this manuscript the effect of an acute ip administration of ACS14 and of its dithiolethione moiety (5-(4-hydroxyphenyl)-3H-1,2-dithiole-3-thione, ADTOH) on the overall thiol content of rat tissues and on the main enzymes involved in the maintenance of thiol homeostasis is reported. ACS14 and ADTOH treatments were shown to induce a significant increase not only of GSH but also of cysteine in plasma and in several rat tissues as well as of H(2)S plasma levels. Conversely, a significant decrease of homocysteine in most rat organs and in plasma was observed. Most of these phenomena are supposed to be linked to the elevated intracellular levels of cysteine induced by treatments with either ACS14 or ADTOH.

Single oral dose study of two isosorbide-based aspirin prodrugs in the dog

The objective of this study was to compare two aspirin prodrugs, isosorbide diaspirinate (ISDA) and a nitroaspirin (ISMNA), with aspirin in terms of effects on dog platelet function after administration of a single oral dose. Groups of six dogs were administered ISDA (2 mg kg−1), ISMNA (4 mg kg−1) or aspirin (2 mg kg−1). Blood was sampled at 1, 2, 4, 8, 12 and 24 h post-dosing and evaluated for capacity to generate post-clotting thromboxane (TX)B2. The aggregation response to arachidonic acid (AA) (100 μM), ADP (30 μM) or collagen (10 μg mL−1) was estimated at each time-point using the whole blood impedance method. Plasma ISMN following oral administration of ISMNA was also measured and compared with plasma ISMN following administration of a physical mixture of ISMN and aspirin. ISDA administration (2 mg kg−1) was associated with a significant reduction (P&lt; 0.05) in serum TXB2 at 12 and 24 h (&gt;90%) post-dosing and persistent inhibition of AA-induced platelet aggregation. ISDA administration caused a more marked depression of post-clotting TXB2 levels than aspirin in this study, although its ability to inhibit platelet aggregation was less consistent than that of aspirin. The nitroaspirin ISMNA was least effective at inhibiting platelet aggregation response or TXB2 production. The ISMN AUC0–24h for the ISMNA-treated dogs was 77% of that for the physical mix-treated dogs and the tmax was delayed. This study indicates that the two aspirin esters cause aspirin-like effects on platelet function, probably through aspirin release, when administered orally to dogs.

[Acoustic rhinometry in the evaluation of intranasal aspirin challenge]

Nasal lysine aspirin (Lys-ASA) challenge is an alternative to oral and bronchial challenges in the diagnosis of aspirin (ASA) hypersensitivity. The aim of the study was to evaluate the acoustic rhinometry as an objective method of assessment of Lys-ASA nasal challenge.

MATERIAL AND METHODS

Twenty patients with aspirin induced asthma (ASA-S) and 10 controls (ASA-NS group: 5 patients with allergic rhinitis and 5 healthy subjects) were included. Nasal challenge was performed with placebo (saline) and 14.4 mg of Lys-ASA introduced as aerosol to both nostrils (total dose: 16 mg of acetylsalicylic acid). Measurements of nasal volume bilaterally were performed with the use of acoustic rhinometer before and 1, 2, 4 and 24 hours after the challenge. For further analysis the sum of both nasal cavities volume at the level of 2 to 5 cm from nostrils was used.

RESULTS

Mean total bilateral volume in ASA-S group after placebo was: 7.74, 6.21, 7.11, 7.12, 7.24 cm(3) and 7.24, 5.77, 6.31, 6.27, 6.98 cm(3) after Lys-ASA (before and after 1, 2, 4 and 24 hours, respectively; p = 0,048 and p = 0,02, in 2nd and 4th hour, Lys-ASA v. placebo, Wilcoxon's test). With cut off point of nasal volume decrease by 10% in the 1st hour the sensitivity of the test was 70%, specificity 60%, positive predictive value 77.78% and negative predictive value 50%.

CONCLUSIONS

In conclusion, acoustic rhinometry with measurement of nasal cavities volume changes at 2 to 5 cm from nostrils does not appear to be sufficiently sensitive and specific as a single method for evaluation of studied challenge method.