The aim of this thesis was to contribute to the standardization and validation of expiratory flow parameters independent of NO testing, particularly alveolar concentration (CANO) and bronchial NO flux (JawNO) in children and adolescents with allergic respiratory diseases. The thesis was created in the time of increased interest of medicine professionals in non-invasive examination methods and targeted therapeutic influence of inflammation in small airways in asthmatics. After the standardization and validation of clinical benefits, the measurement of concentrations of nitric oxide (FENO) in the air exhaled through the mouth with the speed of 50 ml/s was validated for the evaluation of eosinophilic airway inflammation in patients with asthma and started to be widely used in clinical practice. Currently, there is an ongoing research focused on a new method for FENO measurement at several flow rates, which uses physiological models of NO transfer in exhaled air, allowing to quantify the amount of NO in an indirect way and to monitor the intensity of the inflammatory processes in distal and proximal airways non- invasively. In groups of children and adolescents with allergic rhinitis and / or bronchial asthma and their healthy peers (aged 6 -19 years), the concentration of FENO was examined using online...

Fundamento: O óxido nítrico inalatório (NOi) tem sido utilizado para controle e tratamento da hipertensão pulmonar (HP) durante ou imediatamente após cirurgias cardiotorácicas. Entretanto, seus efeitos comparados a outras medicações vasodilatadoras ainda são controversos. Objetivo: Revisar sistematicamente os efeitos do NOi comparado com outras medicações vasodilatadoras administrado durante ou imediatamente após cirurgias cardiotorácicas, sobre variáveis hemodinâmicas e oxigenação, em pacientes com HP. Métodos: Foi realizada uma busca sistemática nas bases de dados Cochrane CENTRAL, MEDLINE, Lilacs, PEDro e Embase, além de busca manual em referências de estudos publicados até maio de 2015. Foram incluídos ensaios clínicos randomizados (ECRs) que compararam NOi vs. outras medicações vasodilatadoras (inalatórias ou intravenosas) e que analisaram índice de oxigenação (relação PaO2/FiO2) e variáveis hemodinâmicas como pressão média da artéria pulmonar (PMAP), resistência vascular pulmonar (RVP), fração de ejeção do ventrículo direito (FEVD), saturação venosa mista de oxigênio (SvO2), índice cardíaco (IC), pressão venosa central (PVC), frequência cárdica (FC), pressão arterial média sistêmica (PAM), e resistência vascular sistêmica (RVS). Resultados: Foram identificados 2.561 artigos, totalizando seis ECRs incluídos. O uso do NOi comparado com outras medicações vasodilatadoras não promoveu alterações na relação PaO2/FiO2, PMAP, RVP, IC, FEVD, SvO2, PVC e RVS, entretanto houve redução na FC (-5,47 bpm; IC95%: -10,87 a -0,06) comparado com medicações inalatórias e aumento na PAM (9,30 mmHg; IC95%: 3,94 a 14,65; I2: 86%) comparado com medicações vasodilatadoras intravenosas. Conclusões: O uso do NOi não promoveu alterações na relação PaO2/FiO2 e nas variáveis hemodinâmicas comparado com outras medicações vasodilatadoras, exceto na FC onde houve redução e na PAM onde houve aumento, durante ou imediatamente após cirurgias cardiotorácicas em pacientes adultos com HP. / Introduction: The inhaled nitric oxide (INO) has been used for control and treatment of pulmonary hypertension (PH) during or immediately after cardiothoracic surgery. Although, the effects when compared to other vasodilator medications are still controversial. Objectives: The purpose of this study was to systematically review the effects of INO compared with other vasodilatory drugs administered during or immediately after cardiothoracic surgeries on hemodynamics and oxygenation variables in patients with PH. Methods: A systematic research was conducted in the databases Cochrane CENTRAL, MEDLINE, Lilacs, PEDro e Embase, in addition a manual search at references of published studies until May 2015. Randomised trials (RCTs) were included, comparing INO vs. other vasodilator medications (inhaled or intravenous), that analyzed the oxygenation index (ratio PaO2/FiO2) and hemodynamic variables: mean pulmonary artery pressure (MPAP), pulmonary vascular resistance (PVR), right ventricular ejection fraction (RVEF), mixed venous oxygen saturation (SvO2) , cardiac index (CI), central venous pressure (CVP), cardia rate (HR), mean systemic arterial pressure (MAP) and systemic vascular resistance (SVR). Results: We identified 2561 articles, being only six ECRs included. The use of NOi compared to other vasodilator medications did not change the ratio PaO2/FiO2, MPAP, PVR, CI, RVEF, SvO2, CVP e SVR, however there was a reduction in HR (-5,47 bpm; IC95%: -10,87 a -0,06) compared to inhaled medications and increased MAP (9,30 mmHg; IC95%: 3,94 a 14,65; I2: 86%) compared with intravenous vasodilator medications. Conclusion: The use of INO did not change ratio PaO2/FiO2 and hemodynamic variables, compared with other vasodilator medications, except HR where has been found a reduction, and MAP where has been found an increasing, during or immediately after thoracic cardiovascular surgery in adult patients with HP.

Submitted by Renata Oliveira Samuel null (re_samuel@hotmail.com) on 2016-05-09T13:56:38Z No. of bitstreams: 1 Tese Doutorado Renata - 04-05-16.pdf: 2214962 bytes, checksum: b43400238a9850e49f42a7d10d876c58 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-05-12T17:47:39Z (GMT) No. of bitstreams: 1 samuel_ro_dr_araca.pdf: 2214962 bytes, checksum: b43400238a9850e49f42a7d10d876c58 (MD5) / Made available in DSpace on 2016-05-12T17:47:39Z (GMT). No. of bitstreams: 1 samuel_ro_dr_araca.pdf: 2214962 bytes, checksum: b43400238a9850e49f42a7d10d876c58 (MD5) Previous issue date: 2016-03-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O objetivo deste trabalho foi colaborar com o entendimento dos mecanismos que envolvem a relação entre as infeções de origem endodôntica e o estado de homeostasia corpórea. Para isso investigamos o perfil inflamatório local da periodontite apical induzida e relacionamos com alterações no perfil sistêmico em ratos portadores de uma ou múltiplas infecções de origem endodôntica. Foram utilizados 30 ratos da linhagem Wistar distribuídos em 3 grupos de 10 animais: ratos saudáveis; 1AP – ratos com infecção endodôntica em um elemento dentário; 4AP ratos com infecções endodônticas em 4 elementos dentários. Após 30 dias, foi coletado sangue por punção cardíaca para a realização do hemograma (hemácias, volume globular, hemoglobina, VCM, CHCM, leucócitos, neutrófilos, linfócito, monócito, eosinófilo, basófilo e plaquetas); da quantificação sérica das citocinas pró-inflamatórias (TNF-α, IFNγ, IL-6, IL-17, IL-23) por ELISA e da quantificação de óxido nítrico (NO). Após coleta sanguínea, os animais foram sacrificados, as maxilas e mandíbulas foram processadas para análise em microscopia de luz em coloração de H.E. e para marcação imunoistoquímica dos mediadores inflamatórios supracitados. Os resultados das diferentes análises e a relação entre os achados locais e sistêmicos foram analisados por testes estatísticos específicos para cada caso (p<0,05). Nas análises histológicas, foi confirmada a presença de periodontites apicais no 1AP e 4AP, com infiltrado inflamatório moderado. Além disso, foi observado aumento de todos os mediadores supracitados nas lesões quando comparado aos tecidos saudáveis (p<0.05). Nas análises séricas, foi observado aumento linfócitos, leucócitos, TNF-α, IL-6, IL-17 e IL-23 no 4AP quando comparado aos ratos saudáveis (p<0.05). Além disso, houve diminuição do NO no 1AP e 4AP quando comparados aos ratos saudáveis (p<0.05). O nível de IFNγ não foi diferente entre os grupos (p>0.05). Conclui-se que a presença de periodontite apical em múltiplos elementos dentários pode levar a alterações séricas importantes decorrentes do aumento de linfócitos, leucócitos e das citocinas pró-inflamatórias TNF-α, IL-6, IL-17 e IL-23. Além disso, a periodontite apical em um ou em múltiplos elementos dentários leva a diminuição sérica dos metabólitos do NO. / The aim of this work will contribute to understanding of the mechanisms that involve the relationship between infections of endodontic origin and state of bodily homeostasis. Thus, we propose to investigate the profile of local inflammatory induced apical periodontitis and correlate with changes in the profile systemic model with a onlyl or multiple endodontic infections. It were used 30 Wistar rats divided into three groups of 10 animals each: healthy rats; 1AP - rats with only endodontic infection; 4AP rats with multiple endodontic infections. After 30 days, blood was collected by cardiac puncture for complete blood count (RBCs, packed cell volume, hemoglobin, mean corpuscular volume, mean corpuscular hemoglobin concentration, leukocytes, neutrophil, lymphocyte, monocyte, eosinophil, basophil and platelets), serum quantification of proinflammatory cytokines (IL-17, IL-23, IL-6, TNF-α, IFN-γ) by ELISA and nitric oxide. After blood collection, the animals were killed, the jaws were processed for light microscopy in HE staining and immunohistochemical staining of inflammatory mediators above. The results of the different analyzes and the correlation between the local and systemic findings were analyzed by statistical tests specific to each case (p<0,05). Histological analysis confirmed the presence of apical periodontitis in 1AP and 4AP, with moderate inflammatory infiltrate. Furthermore, it was observed increase of all above mediators in lesions when compared to healthy tissue (p <0.05). In serum analysis, 4AP showed lymphocytes, leukocytes, TNF-α, IL-6, IL-17 and IL-23 increase when compared to healthy rats (p <0.05). Furthermore, there was a decrease of NO in 4AP and 1AP when compared to healthy rats (p <0.05). IFN-γ level was not different between the groups (p>0.05). It is concluded that the presence of apical periodontitis in multiple teeth can lead to significant alterations from increased serum lymphocytes, leukocytes and pro-inflammatory cytokines TNF-α, IL-6, IL- 17 and IL-23. Furthermore, apical periodontitis in only or multiple teeth leads to decrease of serum levels of NO. / FAPESP: 2013/23358-8

Made available in DSpace on 2014-06-11T19:26:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-01-29Bitstream added on 2014-06-13T20:15:33Z : No. of bitstreams: 1 quilles_mb_me_arafcf.pdf: 1069792 bytes, checksum: 9a998cb3ab50238cd5eb1029bf618292 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O câncer, manifestação originada pelo crescimento descontrolado de células, afeta milhões de indivíduos. Os macrófagos são as primeiras células a serem ativadas para participar de uma resposta imunológica propriamente dita, são células capazes de secretar mais de cem produtos biologicamente ativos, entre esses, espécies reativas de nitrogênio e citocinas que atuam no contexto da resposta imunológica e/ou inflamatória. Sabendo que compostos de paládio (II) podem apresentar potenciais atividades anti - tumorais, neste trabalho foram testado os compostos de fórmula geral [Pd(dmba)(Cl)tu] e [Pd(dmba)(N3)tu], nos quais dmba = N,N-dimetilbenzilamina e tu = tiouréia quanto a atividade antiinflamatória, antitumoral e mutagênica dos mesmos.Como droga padrão das reações realizadas foi utilizada a cis-platina. Foi determinada a ação destes compostos frente ao sistema imunológico através, de ensaios de determinação de citotoxicidade mediano (IC50) pela técnica de MTT, óxido nítrico (NO), peróxido de hidrogênio (H2O2), determinação das citocinas IL-1, IL-6, IL-12, TNF-α e IL-10. Além disso, foi determinado a atividade antitumoral dos compostos frente à célula tumoral de Ehrlich, assim como a atividade mutagênica pelo teste de Ames e Ensaio com plasmídio pUC 9.1. Os resultados mostraram produção de NO e das citocinas IL-1, IL-6, IL-12 e TNF-α; moderada produção de H2O2 pelos macrófagos peritoneais de animais normais e animais portadores do tumor de Ehrlich na sua forma sólida, estimulados com os compostos e seus ligantes, assim como a cis-platina. Por outro lado, de maneira contrária às outras citocinas testadas, não houve a produção de IL-10. No que se refere à atividade antitumoral dos compostos testados, estes mostraram efeito citotóxico sobre a linhagen tumoral testada. Com relação à atividade mutagênica, os compostos... / The cancer, manifestation originated by the growth not controlled of cells, affects million of individuals. Macrophages are the first cells to be activated to participate in an immune response itself, are cells to able to secreting more than one hundred biologically active products, among these, reactive nitrogen species and cytokines that act in the context of the immune response and / or inflammatory. Knowing that compounds of palladium (II) can be potential activities anti - tumor in this study was tested compounds of general formula [Pd (Pd) (Cl) tu] and [Pd (Pd) (N3) tu], where Pd = N, N-dimetilbenzilamina and tu = thiourea as the anti-inflammatory, antitumor and mutagenic of the same. As standard was used the cis-platinum. We determining the action of these compounds against the immune system, for tests to determine the median cytotoxicity (IC50) by the MTT technique, nitric oxide (NO), hydrogen peroxide (H2O2), determination of IL-1, IL-6 , IL-12, TNF-α and IL-10. Moreover, it was determined the antitumor activity of compounds against the Ehrlich tumor cell, as well as mutagenic by the Ames test and test with plasmid pUC 9.1. The results showed NO production and the IL-1, IL-6, IL-12 and TNF-α, by peritoneal macrophages from normal animals and animals with Ehrlich tumor in solid form was stimulated by the compounds and their ligands as well as cis-platinum. Moreover, in contrary manner to other cytokines tested, there wasn’t production of IL-10, and H2O2. With regard to the antitumor activity of the compounds tested, these showed cytotoxic effect on tumor lineage tested. With respect to mutagenic activity, compounds and ligands weren’t mutagenic in vitro, unlike cis-platinum was shown to be mutagenic, causing mutations in the DNA of Salmonella typhimurium by the Ames test. The compounds and ligants were not also to induce DNA breaks in the plasmid... (Complete abstract click electronic access below)

Made available in DSpace on 2014-06-11T19:32:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-12-01Bitstream added on 2014-06-13T20:43:39Z : No. of bitstreams: 1 maia_dcg_dr_arafcf.pdf: 644698 bytes, checksum: c954f27183fc2d6dfe3edc5c958d5f3c (MD5) / Universidade Estadual Paulista (UNESP) / A esporotricose é uma infecção micótica provocada pelo fungo dimórfico Sporothrix schenckii, causando em geral lesões subcutâneas nodulares e/ou ulcerativas que se proliferam via linfática, porém em raros casos pode provocar infecção sistêmica. O óxido nítrico (NO) é sintetizado através da enzima óxido nítrico sintase induzível (iNOS) em macrófagos ativados. Por outro lado, as citocinas exercem papel importante em todo o processo de ativação das células T e pode influenciar diretamente na resposta imunológica, juntamente com os compostos intermediários do nitrogênio. Para melhor avaliar a inter-relação entre as respostas inata, adaptativa, celular e humoral esse trabalho analisou vários mediadores como a iNOS (arginina marcada por trício), NO (teste de Griess), citocinas ( teste imunoenzimático), transformação linfocitária (incorporação da timidina triciada) e detecção de IgG (teste imunoenzimático). Observou-se que o NO produzido a partir da iNOS causou uma imunossupressão entre a quarta e sexta semana de infecção, levando a uma depressão na produção de algumas citocinas como a IL-1b e o TNF-a, além de inibir a proliferação das células T nas mesmas semanas. A IL-12 como o IFN-g são importantes mediadores da resposta imune celular tipo Th1 e em conjunto com a IL-2 parecem ser produzidos como uma tentativa de proteção do hospedeiro contra a doença. Por outro lado, a IL-10 parece estar relacionada com a suscetibilidade à infecção. Para reverter esse quadro da doença fúngica a IL-6 e a IL-4 podem vir a induzir uma resposta humoral verificada pela produção de anticorpos nas semanas finais da infecção e por fim, levar a remissão da infecção experimental por S. schenckii. / Sporotrichosis is a micotic infection desease caused by dimorphic fungus Sporothrix schenckii, causing in general subcutaneous nodulares and/or ulcerative lesions that proliferate through lymphatic vessels, however in rare cases sistêmic can provoke infection. The nitric oxide (NO) is synthezed through of the enzyme nitric oxide sintase induzível (iNOS) in activated macrophages. On the other hand, the cytokines exert important role in all the process of activation of cells T and can to influence directly in the immunological response, together with intermediate composites of nitrogen. The evaluation between the innate, adaptativa, cellular and humoral response this work were analyzed several mediators as iNOS (arginine H3), NO (Griess reagent), cytokines (immunoenzimatic assay), lymphatic transformation (incorporation of timidine- H3) and detection of IgG (immunoenzimatic assay). We observed that NO the produced from iNOS caused an immunossupression between the fourth and sixth week of infection leading to a depression in the production of some cytokines as the IL-1b and TNF-a, besides inhibiting the proliferation of cells T in the same weeks. The IL-12 as the IFN-g is important mediators of the cellular Th1 response and together with IL-2 seem to being produced as a protection host attempt against the disease. On the other hand, the IL-10 seems to be related with the susceptibility to the infection. To revert this immunological response IL-6 and IL-4 can come to induce an humoral response verified by the antibodies production in the infection final weeks and finally, lead the experimental infection remission by S. schenckii.

Electrocatalytic reduction and oxidation of nitrite using cobalt phthalocyanine derivatives was studied. The detection limit of 1 x 10⁻¹° mol dm⁻³ was achieved when these molecules were employed as catalysts for nitrite detection. The mechanisms for nitrite catalysis were proposed. The position of the peripheral substituents on cobalt porphyrazines (related to cobalt phthalocyanines) affected the catalytic activity of these complexes. The highest activity for nitrite reduction was observed on the cobalt(II) 2,3-tetramethyltetrapyridinoporphyrazine ([CoTm-2,3-tppa]⁴⁺), with cobalt phthalocyanine showing the lowest activity, and the cobalt(II) 3,4- tetramethyltetrapyridinoporphyrazine ([CoTm-3,4-tppa]⁴⁺), showing intermediate behaviour. A mixture of a negatively charged cobalt(II) tetrasulfophthalocyanine ([Co¹¹TSPc]⁴⁻) and a positively charged [CoTm-3,4-tppa]⁴⁺ showed better activity for nitrite reduction than did the individual components. Cobalt porphyrazines lowered the potentials for nitrite reduction in that peaking was observed, as opposed to cobalt phthalocyanine, where only the increase in currents was observed without peaking. Using the cobalt phthalocyanine derivatives, nitrite can be reduced to ammonia with high current efficiency. A glassy carbon electrode modified with [Co¹¹TSPc]⁴⁻ was employed for the determination of nitrite. Nitrate had an insignificant effect on nitrite oxidation on these modified electrodes. Electrocatalytic determination of S0₂ was studied as a function of pH at a glassy carbon electrode modified with iron(II) tetrasulfophthalocaynine. It was found that depending on pH, S0₂.xH₂0, HS0₃⁻ and/or SO₃²⁻ are the main compounds in solution and that these compounds behave differently at the electrode surface. Detection limits ranging from 4.0 ± 0.1 x 10⁻⁵ to 7.5 ± 0.1 x 10⁻⁵ mol dm⁻³ depending on pH were observed. Similar results were obtained when cobalt(II) tetrasulfophthalocaynine was employed for S0₂ catalysis under the same experimental conditions. Cysteine and histidine determination using oxidation currents was performed on glassy carbon electrodes modified with [CoTm-3,4-tppa]⁴⁺ (represented as [CoTm-3,4-tppa]⁴⁺-GCE) in pH 7 Tris buffer. The detection limit of 1.0 x 10⁻⁵ mol dm⁻³ for cysteine and 2.24 x 10⁻⁷ mol dm⁻³ for histidine were obtained. Cyanide can be detected down to 1 x 10⁻¹¹ mol dm⁻³ using [CoTm-3,4-tppa]⁴⁺-GCE in pH 10.8 buffer. Cyanide and S0₂ coordinate to the [CoTSPc]⁴⁻ species. The coordination is accompanied by oxidation of the central Co(II) metal, forming a [Co¹¹¹CoTSPc]³⁻ species. The rate constants for cyanide coordination to the [Co¹¹TSPc]⁴⁻ complex are larger than those reported for the coordination of cyanide to FePc and RuPc complexes in non-aqueous media. Autoreduction of [Co¹¹Tmtppa]⁴⁺ occurred in the presence of either histidine or cysteine, with the formation of metal reduced species, [Co¹Tmtppa(-2)]³⁺. Nitric oxide and nitrite coordinate to the [Co¹¹Tmtppa]⁴⁺ species, without auto-reduction of this species, which was observed for cysteine or histidine. The use of [Co¹¹TSPc]⁴ resulted in improved rate of interaction with nitrite when compared to the [Co¹¹Tmtppa]⁴⁺ species.

Doctor of Philosophy / Department of Anatomy and Physiology / David C. Poole / The purpose of this dissertation is to expand our knowledge on the physiological effects of the ubiquitous signaling molecule nitric oxide (NO). Focus is given to the impacts of the nitrate (NO[subscript]3[superscript]-) nitrite (NO[subscript]2[superscript]-) NO pathway on skeletal muscle vascular and metabolic function during exercise. The NO[subscript]3[superscript]--NO[subscript]2[superscript]--NO pathway has garnered tremendous research interest due to its ability to upregulate NO bioavailability independently of NO synthase (NOS) function and thus impact the metabolic responses to exercise. Chapter 2 demonstrates that NO[subscript]3[superscript]- supplementation via beetroot juice (BR) augments the skeletal muscle vascular responses to exercise. Five days of BR supplementation resulted in a significantly higher skeletal muscle blood flow (BF) and vascular conductance (VC) during exercise when compared to control. The increases in BF and VC were preferentially directed to muscles and muscle portions comprised predominantly of fast twitch fibers. Furthermore, exercising blood [lactate] was reduced, suggesting improved metabolic control. In chapter 3, BR resulted in a slower fall in the microvascular PO[subscript]2 (PO[subscript]2[subscript]m[subscript]v, the soul driving force for blood myocyte O[subscript]2 flux) during the crucial rest-contraction transition thereby preserving the pressure head needed to move O[subscript]2 from the capillary into the myocyte. Chapter 4 examines the effects of BR on fast vs. slow twitch muscles in which BR raised the PO[subscript]2[subscript]m[subscript]v during the steady state of muscle contractions in fast but not slow twitch muscles, likely due to the lower PO[subscript]2[subscript]m[subscript]v at rest and throughout muscle contractions within these tissues. Chapter 5 investigates the effects of direct arterial NO[subscript]2[superscript]- infusion on skeletal muscle BF and VC during exercise in rats with NOS blockade via N[superscript]G-nitro-L arginine methyl ester. NO[subscript]2[superscript]- infusion restored MAP and VC to levels observed in healthy control animals (with intact NOS function) highlighting the potential for a NO[subscript]2[superscript]- based therapy to positively impact vascular function in those with compromised NOS function such that is evident in many prevalent diseases. These results provide crucial mechanistic insight into the improved exercise tolerance observed in humans following NO[subscript]3[superscript]- supplementation whilst also challenging our current understanding of NO’s role in physiology and pathophysiology.

Master of Science / Kinesiology / Timothy I. Musch / Exercise intolerance characteristic of diseases such as chronic heart failure (CHF) and diabetes is associated with reduced nitric oxide (NO) bioavailability from nitric oxide synthase (NOS), resulting in an impaired microvascular O₂ driving pressure (PO₂mv: O₂ delivery – O₂ utilization) and metabolic control. Infusions of the potent NO donor sodium nitroprusside augment NO bioavailability yet decrease mean arterial pressure (MAP) thereby reducing its potential efficacy for patient populations. To eliminate or reduce hypotensive sequellae NO₂⁻ was superfused onto the spinotrapezius muscle. It was hypothesized that local NO₂⁻ administration would elevate resting PO₂mv and slow PO₂mv kinetics (increased τ: time constant, MRT: mean response time) following the onset of muscle contractions. In 12 anesthetized male Sprague-Dawley rats, PO₂mv of the circulation-intact spinotrapezius muscle was measured by phosphorescence quenching during 180 s of electrically-induced twitch contractions (1 Hz) before and after superfusion of NaNO₂ (30 mM). NO₂⁻ superfusion elevated resting PO₂mv (CON: 28.4 ± 1.1 vs NO₂⁻: 31.6 ± 1.2 mmHg, P ≤ 0.05), τ (CON: 12.3 ± 1.2 vs NO₂⁻: 19.7 ± 2.2 s, P ≤ 0.05) and MRT (CON: 19.3 ± 1.9 vs NO₂⁻: 25.6 ± 3.3 s, P ≤ 0.05). Importantly, these effects occurred in the absence of any reduction in MAP (103 ± 4 vs 105 ± 4 mmHg, pre- and post-superfusion respectively; P ˃ 0.05). These results indicate that NO₂⁻ supplementation delivered to the muscle directly through NO₂⁻ superfusion enhances the blood-myocyte driving pressure of oxygen without compromising MAP at rest and following the onset of muscle contraction. This strategy has substantial clinical utility for a range of ischemic conditions.

The role of inducible nitric oxide synthase (iNOS) and/or nitric oxide (NO) in atherosclerosis remains elusive. Several researchers argued whether iNOS and/or NO are pathogenic or cardio protective. The pathogenesis of atherosclerosis is complex and includes mechanisms associated with inducible nitric oxide synthase (iNOS). We have demonstrated that the expression and function of iNOS may be selectively down regulated by pro-oxidants such as antimycin A and diethyl maleate (DEM). To further explore the underlying mechanisms associated with these effects we have investigated whether antimycin A and/or DEM modulated the activation of key cellular signalling molecules associated with the induction of iNOS. Expression of p38 mitogen activated kinase (MAPK) and Akt were induced by exposure to lipopolysaccharide (LPS) and interferon-gamma (IFN-γ). Oxidative stress (OS) was induced using antimycin A, DEM and hydrogen peroxide (H2O2). All three OS inducers caused a significant generation of free radicals whereas only antimycin A and DEM generated superoxide radical (O2-). Also nitrite production and iNOS expression may be down regulated, in part; by pro-oxidants generating O2- but not hydroxyl radicals (OH-). Antimycin A and DEM concentration dependently inhibited the phosphorylation of p38 MAPK and Akt and this was restored when the cells were pre-treated with Atorvastatin whereas H2O2 was without any significant effect. Taken together, the data suggest novel actions for both pro-oxidants and atorvastatin which may have important implications in coronary artery disease where suppression of iNOS may be deleterious and maintaining its expression may be cardio-protective.

Natural therapies such as Aged Garlic Extract (AGE) have displayed cardioprotective properties, with studies indicating that AGE can inhibit platelet aggregation both in vivo and in vitro. The mechanism of inhibition induced by AGE is proposed to be due to AGE exerting effects upon several targets within platelets, including calcium and cyclic adenosine monophosphate (cAMP). The effect of AGE upon the other cyclic nucleotide, cyclic guanosine monophosphate (cGMP) is currently unknown. The aims therefore of this project are to identify the effect of AGE upon platelet cGMP, as well as associated signaling molecules including nitric oxide (NO) and cAMP.It was found that the NO donor 3-morpholinosydnonimine (Sin-1) in high concentrations along with the presence of specific inhibitors inhibited platelet aggregation independently of cGMP. Experimentation using chemical inhibitors also displayed erratic results in the presence of high concentrations of AGE, indicating that AGE was influencing the binding of such inhibitors. The results of in vitro experiments indicated that AGE moderately increases intraplatelet cGMP, whereas intraplatelet cAMP is significantly increased. it is proposed that the main mechanism of inhibition caused by AGE is due to increases in cAMP. As intraplatelet cAMP can also be influenced by intraplatelet cGMP, it is likely that cAMP is increased directly and indirectly by AGE.Evidence provided in the present study supports the proposed theory that the mechanisms of inhibition of platelet aggregation by AGE is multimechanistic. More specifically inhibition of platelet aggregation by AGE is due to AGE increasing intraplatelet cyclic nucleotides, reducing the expression of key receptors such as GPIIb/IIIa and inhibiting agonist induced platelet shape change. As AGE can inhibit platelet aggregation, which is a key risk factor in cardiovascular disease, the consumption of AGE would be beneficial to those who are at risk of cardiovascular episodes.