RESUMO
INTRODUCTION: The brain-derived neurotrophic factor (BDNF) and transcription nuclear factor erythroid 2-related factor-2 (NRF-2) play an important role in Alzheimer's disease (AD). However, the interactive involvement of BDNF and NRF-2 in respect to antioxidant mechanisms in different parts of the AD brain is still unclear. Considering the above condition, used S-nitrosoglutathione (GSNO) to examine whether it modulates the BDNF and NRF-2 levels to activate signaling pathway to promote antioxidant levels in AD brains. METHOD: AD was induced by intracerebroventricular infusion of streptozotocin (ICV-STZ, 3 mg/kg) in Wistar rats. The effect of GSNO was analyzed by evaluating the retention of memory in months 1, 2, and 3. After the behavior study, rats were sacrificed and accessed the amyloid beta (Aß)-40, Aß42, glutathione (GSH), BDNF, and NRF-2 levels in the hippocampus, cortex, and amygdala tissue. RESULTS: Pretreatment with GSNO (50 µg/kg/intraperitoneal/day) restored the BDNF, and NRF-2 levels toward normalcy as compared with ICV-STZ + saline-treated animals. Also, GSNO treatment reversed the oxidative stress and increased the GSH levels toward normal levels. Further, reduced Aß levels and neuronal loss in different brain regions. As a result, GSNO treatment improved the cognitive deficits in ICV-STZ-treated rats. CONCLUSION: The results showed that endogenous nitric oxide donor GSNO improved the cognitive deficits and ICV-STZ-induced AD pathological conditions, possibly via attenuating the oxidative stress. Hence, the above finding supported that GSNO treatment may activate BDNF and NRF-2 antioxidant signaling pathways in the AD brain to normalize oxidative stress, which is the main causative factor for ICV-STZ-induced AD pathogenesis.
Assuntos
Doença de Alzheimer , Fator Neurotrófico Derivado do Encéfalo , Modelos Animais de Doenças , Transtornos da Memória , Fator 2 Relacionado a NF-E2 , Estresse Oxidativo , Ratos Wistar , S-Nitrosoglutationa , Transdução de Sinais , Estreptozocina , Animais , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Estresse Oxidativo/efeitos dos fármacos , S-Nitrosoglutationa/farmacologia , S-Nitrosoglutationa/administração & dosagem , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Ratos , Transdução de Sinais/efeitos dos fármacos , Masculino , Estreptozocina/farmacologia , Estreptozocina/administração & dosagem , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/tratamento farmacológico , Antioxidantes/farmacologia , Antioxidantes/administração & dosagemRESUMO
Rheumatoid arthritis (RA) is characterized by high level of reactive oxygen species (ROS) and proinflammatory cytokines, which facilitate the activation of the inflammatory signaling such as NF-κB pathway and exacerbate the development of inflammation. Herein, we designed a nanodrug by encapsulating the NO donor S-nitrosoglutathione (GSNO) into an emulsion and coating the surface with a polydopamine (PDA) layer to yield GSNO@PDA, which simultaneously scavenged the extra ROS and suppressed NF-κB signaling for potent RA treatment. To enhance the cellular uptake and NO generation efficiency, dextran sulfate (DS) and Cu2+ were anchored on the surface of GSNO@PDA to obtain the final formulation GSNO@PDA@DS. Our results demonstrated that GSNO@PDA@DS were successfully prepared and the modification of DS effectively boosted the cellular uptake of GSNO@PDA@DS. Moreover, GSNO@PDA@DS lowered cellular ROS and elevated intracellular NO, resulting in a decrease of M1 phenotype, inhibition of NF-κB pathway and down-regulation of proinflammatory cytokine tumor necrosis factor-α (TNF-α). Further in vivo studies confirmed that GSNO@PDA@DS significantly relieved symptoms and bone erosion by regulating the microenvironment of RA, highlighting the potential of GSNO@PDA@DS for RA therapy through ROS scavenging and NO-mediated suppression of inflammatory signaling.
Assuntos
Artrite Reumatoide , NF-kappa B , Doadores de Óxido Nítrico , Polímeros , Espécies Reativas de Oxigênio , S-Nitrosoglutationa , Espécies Reativas de Oxigênio/metabolismo , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Animais , Doadores de Óxido Nítrico/farmacologia , Doadores de Óxido Nítrico/administração & dosagem , Camundongos , NF-kappa B/metabolismo , S-Nitrosoglutationa/farmacologia , S-Nitrosoglutationa/administração & dosagem , Células RAW 264.7 , Polímeros/química , Indóis/farmacologia , Indóis/administração & dosagem , Sequestradores de Radicais Livres/farmacologia , Sequestradores de Radicais Livres/administração & dosagem , Sinergismo Farmacológico , Masculino , Transdução de Sinais/efeitos dos fármacos , Sulfato de Dextrana , Fator de Necrose Tumoral alfa/metabolismo , Óxido Nítrico/metabolismo , Sistemas de Liberação de Medicamentos/métodosRESUMO
The COVID-19 pandemic has escalated the occurrence of hypoxia including thrombotic stroke worldwide, for which nitric oxide (NO) therapy seems very promising and translatable. Therefore, various modes/routes of NO-delivery are now being tested in different clinical trials for safer, faster, and more effective interventions against ischemic insults. Intravenous (IV) infusion of S-Nitrosoglutathione (GSNO), the major endogenous molecular pool of NO, has been reported to protect against mechanical cerebral ischemia-reperfusion (IR); however, it has been never tested in any kind of "clinically" relevant thromboembolic stroke models with or without comorbidities and in combination with the thrombolytic reperfusion therapy. Moreover, "IV-effects" of higher dose of GSNO following IR-injury have been contradicted to augment stroke injury. Herein, we tested the hypothesis that nebulization of low-dose GSNO will not alter blood pressure (BP) and will mitigate stroke injury in diabetic mice via enhanced cerebral blood flow (CBF) and brain tissue oxygenation (PbtO2). GSNO-nebulization (200 µg/kgbwt) did not alter BP, but augmented the restoration of CBF, improved behavioral outcomes and reduced stroke injury. Moreover, GSNO-nebulization increased early reoxygenation of brain tissue/PbtO2 as measured at 6.5 h post-stroke following thrombolytic reperfusion, and enervated unwanted effects of late thrombolysis in diabetic stroke. We conclude that the GSNO-nebulization is safe and effective for enhancing collateral microvascular perfusion in the early hours following stroke. Hence, nebulized-GSNO therapy has the potential to be developed and translated into an affordable field therapy against ischemic events including strokes, particularly in developing countries with limited healthcare infrastructure.
Assuntos
Complicações do Diabetes/tratamento farmacológico , Diabetes Mellitus/tratamento farmacológico , Hemorragia/prevenção & controle , S-Nitrosoglutationa/administração & dosagem , Acidente Vascular Cerebral/complicações , Terapia Trombolítica/efeitos adversos , Animais , Comportamento Animal , Pressão Sanguínea , Barreira Hematoencefálica , COVID-19/epidemiologia , Hemorragia/complicações , Hipóxia , Infusões Intravenosas , Fluxometria por Laser-Doppler , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microcirculação , Nebulizadores e Vaporizadores , Fármacos Neuroprotetores/farmacologia , Perfusão , Traumatismo por Reperfusão/tratamento farmacológico , Risco , Estresse MecânicoRESUMO
The epigenetic signatures associated with cognitive decline driven by lack of estrogen in post-menopausal state, is not well-understood. The present study is an attempt to unravel the epigenetic mechanisms involved in cognitive impairment preceding ovariectomy in mice and evaluate the protective effects of S-nitrosoglutathione (GSNO). A significant decline in cognitive functions was observed in mice following ovariectomy as assessed by Morris water maze and Novel object recognition test. Administration of GSNO (100⯵g/kg body weight, orally) daily for 4â¯weeks was found to ameliorate cognitive deficits observed in ovariectomised (OVX) mice. The activity of histone acetyl-transferase (HAT) was significantly disrupted in cortex and hippocampus of OVX mice. This was accompanied by increased activity of histone deacetylase (HDAC) and increased levels of HDAC-2, HDAC-3 causing lowered acetylated histone (H)3 levels. Reduced H3 acetylation triggers epigenetic repression of brain derived neurotrophic factor (BDNF) in cortex and hippocampus of OVX mice that may be responsible for neuronal damage and cognitive impairment. GSNO supplementation to OVX mice was able to reinstate HAT(CBP/p300) and HDAC balance through S-nitrosylation. GSNO restored histone acetylation at BDNF promoters (pII, pIV) thereby ameliorating BDNF levels and improving brain morphology and cognition. The study suggests that GSNO improves cognitive function in OVX mice by modulating epigenetic programming.
Assuntos
Disfunção Cognitiva/prevenção & controle , Epigênese Genética/efeitos dos fármacos , S-Nitrosoglutationa/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/sangue , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Imunoprecipitação da Cromatina , Estradiol/sangue , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Histonas/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Ovariectomia , S-Nitrosoglutationa/administração & dosagemRESUMO
BACKGROUND AND PURPOSE: Angiotensin II (AngII) and NO regulate the cerebral circulation. AngII AT1 receptors exert ligand-dependent and ligand-independent (myogenic tone [MT]) vasoconstriction of cerebral vessels. NO induces post-translational modifications of proteins such as S-nitrosation (redox modification of cysteine residues). In cultured cells, S-nitrosation decreases AngII's affinity for the AT1 receptor. The present work evaluated the functional consequences of S-nitrosation on both AngII-dependent and AngII-independent cerebrovascular responses. EXPERIMENTAL APPROACH: S-Nitrosation was induced in rat isolated middle cerebral arteries by pretreatment with the NO donors, S-nitrosoglutathione (GSNO) or sodium nitroprusside (SNP). Agonist-dependent activation of AT1 receptors was evaluated by obtaining concentration-response curves to AngII. Ligand-independent activation of AT1 receptors was evaluated by calculating MT (active vs. passive diameter) at pressures ranging from 20 to 200 mmHg in the presence or not of a selective AT1 receptor inverse agonist. KEY RESULTS: GSNO or SNP completely abolished the AngII-dependent AT1 receptor-mediated vasoconstriction of cerebral arteries. GSNO had no impact on responses to other vasoconstrictors sharing (phenylephrine, U46619) or not (5-HT) the same signalling pathway. MT was reduced by GSNO, and the addition of losartan did not further decrease MT, suggesting that GSNO blocks AT1 receptor-dependent MT. Ascorbate (which reduces S-nitrosated compounds) restored the response to AngII but not the soluble GC inhibitor ODQ, suggesting that these effects are mediated by S-nitrosation rather than by S-nitrosylation. CONCLUSIONS AND IMPLICATIONS: In rat middle cerebral arteries, GSNO pretreatment specifically affects the AT1 receptor and reduces both AngII-dependent and AngII-independent activation, most likely through AT1 receptor S-nitrosation.
Assuntos
Artérias Cerebrais/efeitos dos fármacos , Receptor Tipo 1 de Angiotensina/metabolismo , S-Nitrosoglutationa/farmacologia , Angiotensina II/farmacologia , Animais , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Ligantes , Masculino , Óxido Nítrico/metabolismo , Nitrosação/efeitos dos fármacos , Ratos , Ratos Wistar , S-Nitrosoglutationa/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-AtividadeRESUMO
Methicillin-resistant Staphylococcus aureus (MRSA)-infected wounds have become a significant clinical issue worldwide. Recently, nitric oxide (NO) has emerged as a potent antibacterial agent against MRSA infections and a wound-healing enhancer. Nevertheless, clinical applications of NO have been largely restricted by its gaseous state and short half-life. In this study, our aim was to develop S-nitrosoglutathione (GSNO, an endogenous NO donor)-loaded poly(lactic-co-glycolic acid) [PLGA] microparticles (GSNO-MPs) that release NO over a prolonged period, to accelerate the healing of MRSA-infected wounds with less frequent dosing. GSNO was successfully encapsulated into PLGA microparticles by a solid-in-oil-in-water emulsion solvent evaporation method. Scanning electron microscopy and X-ray diffraction analyses confirmed the successful fabrication of GSNO-MPs. The latter released NO in a prolonged manner over 7â¯days and exerted a remarkable antibacterial activity against MRSA in a concentration- and time-dependent manner. Moreover, GSNO-MPs had good antibacterial efficacy and were found to accelerate wound healing in a mouse model of MRSA-infected wounds. Therefore, NO-releasing MPs devised in this study may be a promising option for the treatment of cutaneous wounds infected by drug-resistant bacteria such as MRSA.
Assuntos
S-Nitrosoglutationa/administração & dosagem , Infecções Estafilocócicas/tratamento farmacológico , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Preparações de Ação Retardada , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Portadores de Fármacos/química , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Microscopia Eletrônica de Varredura , Microesferas , Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico/administração & dosagem , Doadores de Óxido Nítrico/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , S-Nitrosoglutationa/farmacologia , Infecções Estafilocócicas/microbiologia , Fatores de Tempo , Difração de Raios XRESUMO
The nitric oxide (NO)/cyclic GMP signaling pathway has been suggested to be important in the formation of olfactory memory in insects. However, the molecular targets of the NO signaling cascade in the central neurons associated with olfactory learning and memory have not been fully analyzed. In this study, we investigated the effects of NO donors on single voltage-dependent Na+ channels in intrinsic neurons, called Kenyon cells, in the mushroom bodies in the brain of the cricket. Step depolarization on cell-attached patch membranes induces single-channel currents with fast-activating and -inactivating brief openings at the beginning of the voltage steps followed by more persistently recurring brief openings all along the 150-ms pulses. Application of the NO donor S-nitrosoglutathione (GSNO) increased the number of channel openings of both types of single Na+ channels. This excitatory effect of GSNO on the activity of these Na+ channels was diminished by KT5823, an inhibitor of protein kinase G (PKG), indicating an involvement of PKG in the downstream pathway of NO. Application of KT5823 alone decreased the activity of the persistent Na+ channels without significant effects on the fast-inactivating Na+ channels. The membrane-permeable cGMP analog 8Br-cGMP increased the number of channel openings of both types of single Na+ channels, similar to the action of NO. Taken together, these results indicate that NO acts as a critical modulator of both fast-inactivating and persistent Na+ channels and that persistent Na+ channels are constantly upregulated by the endogenous cGMP/PKG signaling cascade. NEW & NOTEWORTHY This study clarified that nitric oxide (NO) increases the activity of both fast-inactivating and persistent Na+ channels via the cGMP/PKG signaling cascade in cricket Kenyon cells. The persistent Na+ channels are also found to be upregulated constantly by endogenous cGMP/PKG signaling. On the basis of the present results and the results of previous studies, we propose a hypothetical model explaining NO production and NO-dependent memory formation in cricket large Kenyon cells.
Assuntos
Proteínas Quinases Dependentes de GMP Cíclico/fisiologia , GMP Cíclico/fisiologia , Gryllidae/fisiologia , Corpos Pedunculados/fisiologia , Neurônios/fisiologia , Óxido Nítrico/fisiologia , Canais de Sódio Disparados por Voltagem/fisiologia , Animais , Masculino , Potenciais da Membrana , Modelos Neurológicos , Doadores de Óxido Nítrico/administração & dosagem , S-Nitrosoglutationa/administração & dosagem , Transdução de SinaisRESUMO
Diabetes is associated with increased blood brain barrier (BBB) permeability resulting in neurological deficits. The present study investigated the role of S-nitrosoglutathione (GSNO) on tight junction proteins and cell adhesion molecules in streptozotocin-induced diabetic mice. Diabetes was induced by intraperitoneal injection of streptozotocin (40â¯mg/kg body weight) for 5 days in mice. GSNO was administered daily (100⯵g/kg body weight, orally) for 8 weeks after the induction of diabetes. A significant decline was observed in the cognitive ability of diabetic animals assessed using radial arm maze test. A significant increase was observed in nitrotyrosine levels in cortex and hippocampus of diabetic mice. Relative mRNA and protein expression of tight junction proteins viz; zona occludens-1 (ZO-1) and occludin were significantly lower in the microvessels isolated from cortex and hippocampus of diabetic animals, whereas expression of claudin-5 was unaltered. Immunofluorescence of tight junction proteins confirmed loss of ZO-1 and occludin in the diabetic brain. Furthermore, significant increase in interstitial cell adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 mRNA and protein levels was observed in diabetic animals. Ultrastructure of microvessels from diabetic brain was also altered thereby confirming BBB disruption. GSNO administration to diabetic animals, on the other hand, was able to ameliorate loss of ZO-1 and occludin as well as normalize ICAM-1 and VCAM-1 expression, restore BBB integrity, and improve cognitive deficits. The findings clearly suggest that GSNO is a therapeutic molecule with potential to protect BBB and prevent diabetes induced neurological deficits.
Assuntos
Barreira Hematoencefálica/metabolismo , Moléculas de Adesão Celular/biossíntese , Hiperglicemia/metabolismo , Fármacos Neuroprotetores/administração & dosagem , S-Nitrosoglutationa/administração & dosagem , Proteínas de Junções Íntimas/biossíntese , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/patologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/prevenção & controle , Hiperglicemia/patologia , Hiperglicemia/prevenção & controle , Masculino , CamundongosRESUMO
The present study evaluated the effects of s-nitrosoglutathione (GSNO), a nitrosothiol and sustained NO releaser, on experimental model of sporadic Alzheimer`s disease (sAD) in rats. Levels of Aß40, Aß42 and BDNF were assessed in brain hippocampal homogenates for correlative purposes. Intracerebroventricular-Streptozotocin (icv-STZ) induced increased escape latencies (acquisition) and reduced time in target quadrant (probe trial) in Morris Water Maze (MWM) test at 3 months post icv-STZ administration. These behavioural changes were associated with increased Aß depositions and lowered BDNF levels in brain hippocampal homogenates. Pre-treatment with GSNO (50⯵g/kg/day), reduced the icv-STZ induced cognitive deficits in acquisition and probe trials in the MWM. The icv-STZ induced elevations in Aß40 and Aß42 and reduced levels of BDNF in hippocampal homogenates were also attenuated after GSNO treatment in these rats. The NO-precursor, l-arginine (100â¯mg/kg) induced similar effects on behavioural and biochemical parameters tested but was marginally less consistent as compared to those seen with GSNO. The results suggest that GSNO ameliorates the cognitive deficits and associated brain biochemical changes in this experimental model of sporadic AD, and NO-BDNF interactions could play crucial role in these effects.
Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/psicologia , Fármacos Neuroprotetores/administração & dosagem , Óxido Nítrico/metabolismo , S-Nitrosoglutationa/administração & dosagem , Doença de Alzheimer/prevenção & controle , Peptídeos beta-Amiloides/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Modelos Animais de Doenças , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Doadores de Óxido Nítrico/metabolismo , Fragmentos de Peptídeos/metabolismo , Ratos Wistar , S-Nitrosoglutationa/metabolismo , Estreptozocina/administração & dosagemRESUMO
AIMS: Cigarette smoke (CS)-mediated acquired cystic fibrosis transmembrane conductance regulator (CFTR)-dysfunction, autophagy-impairment, and resulting inflammatory-oxidative/nitrosative stress leads to chronic obstructive pulmonary disease (COPD)-emphysema pathogenesis. Moreover, nitric oxide (NO) signaling regulates lung function decline, and low serum NO levels that correlates with COPD severity. Hence, we aim to evaluate here the effects and mechanism(s) of S-nitrosoglutathione (GSNO) augmentation in regulating inflammatory-oxidative stress and COPD-emphysema pathogenesis. RESULTS: Our data shows that cystic fibrosis transmembrane conductance regulator (CFTR) colocalizes with aggresome bodies in the lungs of COPD subjects with increasing emphysema severity (Global Initiative for Chronic Obstructive Lung Disease [GOLD] I - IV) compared to nonemphysema controls (GOLD 0). We further demonstrate that treatment with GSNO or S-nitrosoglutathione reductase (GSNOR)-inhibitor (N6022) significantly inhibits cigarette smoke extract (CSE; 5%)-induced decrease in membrane CFTR expression by rescuing it from ubiquitin (Ub)-positive aggresome bodies (p < 0.05). Moreover, GSNO restoration significantly (p < 0.05) decreases CSE-induced reactive oxygen species (ROS) activation and autophagy impairment (decreased accumulation of ubiquitinated proteins in the insoluble protein fractions and restoration of autophagy flux). In addition, GSNO augmentation inhibits protein misfolding as CSE-induced colocalization of ubiquitinated proteins and LC3B (in autophagy bodies) is significantly reduced by GSNO/N6022 treatment. We verified using the preclinical COPD-emphysema murine model that chronic CS (Ch-CS)-induced inflammation (interleukin [IL]-6/IL-1ß levels), aggresome formation (perinuclear coexpression/colocalization of ubiquitinated proteins [Ub] and p62 [impaired autophagy marker], and CFTR), oxidative/nitrosative stress (p-Nrf2, inducible nitric oxide synthase [iNOS], and 3-nitrotyrosine expression), apoptosis (caspase-3/7 activity), and alveolar airspace enlargement (Lm) are significantly (p < 0.05) alleviated by augmenting airway GSNO levels. As a proof of concept, we demonstrate that GSNO augmentation suppresses Ch-CS-induced perinuclear CFTR protein accumulation (p < 0.05), which restores both acquired CFTR dysfunction and autophagy impairment, seen in COPD-emphysema subjects. INNOVATION: GSNO augmentation alleviates CS-induced acquired CFTR dysfunction and resulting autophagy impairment. CONCLUSION: Overall, we found that augmenting GSNO levels controls COPD-emphysema pathogenesis by reducing CS-induced acquired CFTR dysfunction and resulting autophagy impairment and chronic inflammatory-oxidative stress. Antioxid. Redox Signal. 27, 433-451.
Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Enfisema Pulmonar/tratamento farmacológico , S-Nitrosoglutationa/administração & dosagem , Fumaça/efeitos adversos , Animais , Autofagia/efeitos dos fármacos , Benzamidas/farmacologia , Linhagem Celular , Humanos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Agregados Proteicos/efeitos dos fármacos , Enfisema Pulmonar/induzido quimicamente , Enfisema Pulmonar/imunologia , Pirróis/farmacologia , S-Nitrosoglutationa/farmacologia , Produtos do TabacoRESUMO
S-nitrosoglutathione (GSNO) is a nitric oxide (NO) donor, which exerts antioxidant, anti-inflammatory, and microbicidal actions. Intragingival application of GSNO was already shown to decrease alveolar bone loss, inflammation and oxidative stress in an experimental periodontal disease (EPD) model. In the present study, we evaluated the potential therapeutic effect of topical applications of hydroxypropylmethylcellulose (HPMC)/GSNO solutions on EPD in Wistar rats. EPD was induced by placing a sterilized nylon (3.0) thread ligature around the cervix of the second left upper molar of the animals, which received topical applications of a HPMC solutions containing GSNO 2 or 10 mM or vehicle (HPMC solution), 1 h prior to the placement of the ligature and then twice daily until sacrifice on day 11. Treatment with HPMC/GSNO 10 mM solution significantly reduced alveolar bone loss, oxidative stress and TNF-α e IL-1ß levels in the surrounding gingival tissue, and led to a decreased transcription of RANK and TNF-α genes and elevated bone alkaline phosphatase, compared to the HPMC group. In conclusion, topical application of HPMC/GSNO solution is a potential treatment to reduce inflammation and bone loss in periodontal disease.
Assuntos
Derivados da Hipromelose/administração & dosagem , Doenças Periodontais/tratamento farmacológico , S-Nitrosoglutationa/administração & dosagem , Administração Tópica , Perda do Osso Alveolar/tratamento farmacológico , Perda do Osso Alveolar/metabolismo , Perda do Osso Alveolar/patologia , Animais , Modelos Animais de Doenças , Gengiva/efeitos dos fármacos , Gengiva/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Interleucina-1beta/metabolismo , Masculino , Doadores de Óxido Nítrico/administração & dosagem , Óxido Nítrico Sintase Tipo II/metabolismo , Doenças Periodontais/metabolismo , Doenças Periodontais/patologia , Ratos , Ratos Wistar , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Soluções , Fosfatase Ácida Resistente a Tartarato/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Treatment of stroke, especially during the first hours or days, is still lacking. S-nitrosoglutathione (GSNO), a cerebroprotective agent with short life time, may help if administered early with a sustain delivery while avoiding intensive reduction in blood pressure. We developed in situ forming implants (biocompatible biodegradable copolymer) and microparticles (same polymer and solvent emulsified with an external oily phase) of GSNO to lengthen its effects and allow cerebroprotection after a single subcutaneous administration to Wistar rats. Arterial pressure was recorded for 3 days (telemetry, n = 14), whole-blood platelet aggregation up to 13 days (aggregometry, n = 58), and neurological score, cerebral infarct size and edema volume for 2 days after obstruction of the middle cerebral artery by autologous blood clots (n = 30). GSNO-loaded formulations (30 mg/kg) induced a slighter and longer hypotension (-10 vs. -56 ± 6 mmHg mean arterial pressure, 18 h vs. 40 min) than free GSNO at the same dose. The change in pulse pressure (-50%) lasted even up to 42 h for microparticles. GSNO-loaded formulations (30 mg/kg) prevented the transient 24 h hyper-aggregability observed with free GSNO and 7.5 mg/kg-loaded formulations. When injected 2 h after stroke, GSNO-loaded microparticles (30 mg/kg) reduced neurological score at 24 (-62%) and 48 h (-75%) vs. empty microparticles and free GSNO 7.5 mg/kg and, compared to free GSNO, divided infarct size by 10 and edema volume by 8 at 48 h. Corresponding implants reduced infarct size and edema volume by 2.5 to 3 times. The longer (at least 2 days) but slight effects on arterial pressures show sustained delivery of GSNO-loaded formulations (30 mg/kg), which prevent transient platelet hyper-responsiveness and afford cerebroprotection against the consequences of stroke. In conclusion, in situ GSNO-loaded formulations are promising candidates for the treatment of stroke.
Assuntos
Fármacos Neuroprotetores/uso terapêutico , S-Nitrosoglutationa/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Injeções Subcutâneas , Masculino , Microesferas , Fármacos Neuroprotetores/administração & dosagem , Agregação Plaquetária/efeitos dos fármacos , Ratos , Ratos Wistar , S-Nitrosoglutationa/administração & dosagem , TelemetriaRESUMO
S-nitrosoglutathione (GSNO) is a nitric oxide (NO) donor with therapeutic potential for cardiovascular disease treatment. Chronic oral treatment with GSNO is limited by high drug sensitivity to the environment and limited oral bioavailability, requiring the development of delivery systems able to sustain NO release. The present work describes new platforms based on polymer nanocomposite particles for the delivery of GSNO. Five types of optimized nanocomposite particles have been developed (three based on chitosan, two based on alginate sodium). Those nanocomposite particles encapsulate GSNO with high efficiency from 64% to 70% and an average size of 13 to 61 µm compatible with oral delivery. Sustained release of GSNO in vitro was achieved. Indeed, chitosan nanocomposites discharged their payload within 24h; whereas alginate nanocomposites released GSNO more slowly (10% of GSNO was still remaining in the dosage form after 24h). Their cytocompatibility toward intestinal Caco-2 cells (MTT assay) was acceptable (IC50: 6.07 ± 0.07-9.46 ± 0.08 mg/mL), demonstrating their suitability as oral delivery systems for GSNO. These delivery systems presented efficient GSNO loading and sustained release as well as cytocompatibility, showing their promise as a means of improving the oral bioavailability of GSNO and as a potential new treatment.
Assuntos
Alginatos/química , Quitosana/química , Nanocompostos/química , Doadores de Óxido Nítrico/administração & dosagem , S-Nitrosoglutationa/administração & dosagem , Administração Oral , Células CACO-2 , Química Farmacêutica/métodos , Preparações de Ação Retardada , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Humanos , Tamanho da PartículaRESUMO
The anti-tumor activity of the binuclear form of dinitrosyl iron complexes with glutathione against Lewis lung carcinoma, found earlier upon intraperitoneal administration of the complexes, was also observed when this preparation was injected subcutaneously. A 100 µM/kg subcutaneous dose of the complex being used daily (as calculated per one iron atom in binuclear dinitrosyl iron complexes) for 10 or 15 days, inhibited the tumor growth by 43%. The effect was observed during the first two weeks after tumor transplantation. After that, the tumors began to grow at the rate equal to or even higher than that one for control animals. The mean survival time for treated mice exceeded the control values by 30%. Binuclear dinitrosyl iron complexes administered intraperitoneally was also effective against Ca-755 adenocarcinoma. However, in this case the mean survival time for treated animals increased only by 7%. The anti-tumor activity of S-nitrosoglutathione against Lewis lung carcinoma growth inhibition by 70% and Ca-755 adenocarcinoma growth inhibition by 90% was also shown. However, unlike binuclear dinitrosyl iron complexes the anti-tumor effect of S-nitrosoglutathione decreased when a daily dose of the compound increased (from 200 to 400 µM/kg) The initial anti-tumor effect of binuclear dinitrosyl iron complexes and S-nitrosoglutathione is suggested to be due to NO released from both compounds. A subsequent suppression of the effect is determined by the development of anti-nitrosative and anti-oxidant defense systems in tumors.
Assuntos
Carcinoma Pulmonar de Lewis/tratamento farmacológico , Glutationa/administração & dosagem , Ferro/administração & dosagem , Óxidos de Nitrogênio/administração & dosagem , S-Nitrosoglutationa/administração & dosagem , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/metabolismo , Animais , Carcinoma Pulmonar de Lewis/patologia , Cisteína/química , Cisteína/metabolismo , Glutationa/química , Humanos , Ferro/química , Camundongos , Óxido Nítrico/química , Óxido Nítrico/metabolismo , Óxidos de Nitrogênio/química , S-Nitrosoglutationa/químicaRESUMO
Glutathione is an abundant molecule inside erythrocyte, originating S-nitrosoglutathione (GSNO) by reacting with nitric oxide (NO). GSNO has been regarded as a store and transporter of NO, with significant interest as a potential therapeutic agent, acting as an NO donor.NO metabolism inside the erythrocyte generates several derivatives, which can be altered by external and internal stimuli such as acetylcholine (ACh), a natural substrate of acetylcholinesterase (AChE). In spite of the knowledge gained in the last decades concerning NO efflux in erythrocytes little is known regarding erythrocyte GSNO efflux, which has also a significant role in microcirculation. Hence, the objective of this research was to evaluate the efflux of GSNO, concomitant with the efflux of NO, after stimulation with AChE effectors. To achieve these goals, the in vitro effect of AChE modulators - ACh and timolol - in erythrocyte NO and GSNO were studied. Timolol is an erythrocyte AChE inhibitor. Venous blood samples were collected from 18 healthy Caucasian men. For each blood sample, erythrocyte suspensions were obtained and incubated in the absence (controls) and presence of ACh and timolol maleate (10 µM final concentration of each modulator). Both timolol and ACh induced significant GSNO efflux in the erythrocyte when compared to the control; however the efflux was lower in the presence of timolol compared to ACh. Although erythrocyte NO efflux in presence of timolol is similar to the control, the efflux decreased when compared to the ACh treatment. The presence of timolol induces significant decrease of intra-erythrocyte GSNO levels, relative to control and ACh treatment. In conclusion, when erythrocytes were stimulated with ACh or timolol, GSNO efflux occurred associated with NO efflux. These new results bring new insight into the metabolism of erythrocyte NO and new possible therapeutic applications for GSNO.
Assuntos
Acetilcolina/farmacologia , Eritrócitos/efeitos dos fármacos , Óxido Nítrico/sangue , S-Nitrosoglutationa/uso terapêutico , Humanos , Masculino , S-Nitrosoglutationa/administração & dosagemRESUMO
INTRODUCTION: Mucositis induced by anti-neoplastic drugs is an important, dose-limiting and costly side-effect of cancer therapy. AIM: To evaluate the effect of the topical application of S-nitrosoglutathione (GSNO), a nitric oxide donor, on 5-fluorouracil (5-FU)-induced oral mucositis in hamsters. MATERIALS AND METHODS: Oral mucositis was induced in male hamsters by two intraperitoneal administrations of 5-FU on the first and second days of the experiment (60 and 40 mg/kg, respectively) followed by mechanical trauma on the fourth day. Animals received saline, HPMC or HPMC/GSNO (0.1, 0.5 or 2.0 mM) 1 h prior to the 5-FU injection and twice a day for 10 or 14 days. Samples of cheek pouches were harvested for: histopathological analysis, TNF-α and IL-1ß levels, immunohistochemical staining for iNOS, TNF-α, IL-1ß, Ki67 and TGF-ß RII and a TUNEL assay. The presence and levels of 39 bacterial taxa were analyzed using the Checkerboard DNA-DNA hybridization method. The profiles of NO released from the HPMC/GSNO formulations were characterized using chemiluminescence. RESULTS: The HPMC/GSNO formulations were found to provide sustained release of NO for more than 4 h at concentration-dependent rates of 14 to 80 nmol/mL/h. Treatment with HPMC/GSNO (0.5 mM) significantly reduced mucosal damage, inflammatory alterations and cell death associated with 5-FU-induced oral mucositis on day 14 but not on day 10. HPMC/GSNO administration also reversed the inhibitory effect of 5-FU on cell proliferation on day 14. In addition, we observed that the chemotherapy significantly increased the levels and/or prevalence of several bacterial species. CONCLUSION: Topical HPMC/GSNO accelerates mucosal recovery, reduces inflammatory parameters, speeds up re-epithelization and decreases levels of periodontopathic species in mucosal ulcers.
Assuntos
Inflamação/tratamento farmacológico , Neoplasias/tratamento farmacológico , S-Nitrosoglutationa/administração & dosagem , Estomatite/tratamento farmacológico , Administração Tópica , Animais , Cricetinae , Modelos Animais de Doenças , Fluoruracila/efeitos adversos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação/genética , Inflamação/patologia , Interleucina-1beta/biossíntese , Masculino , Neoplasias/patologia , Óxido Nítrico Sintase Tipo II/biossíntese , Estomatite/induzido quimicamente , Estomatite/genética , Estomatite/patologia , Fator de Crescimento Transformador beta/biossíntese , Fator de Necrose Tumoral alfa/biossínteseRESUMO
It has been established that intraperitoneal bolus administration of S-nitrosoglutathione (GS-NO) (12.5µmoles/kg; 10 injections in 10 days), beginning with day 4 after transplantation of two 2-mm autologous fragments of endometrial tissue onto the inner surface of the abdominal wall of rats with surgically induced (experimenta) endometriosis failed to prevent further growth of endometrioid (EMT) and additive tumors, while treatment of animals with dinitrosyl iron complexes (DNIC) with glutathione (12.5µmoles/kg, 10 injections in 10 days) suppressed tumor growth virtually completely. The histological analysis of EMT samples of GS-NO-treated rats revealed pathological changes characteristic of control (non-treated with GS-NO or DNIC) rats with experimental endometriosis. EPR studies established the presence of the active form of ribonucleotide reductase, a specific marker for rapidly proliferating tumors, in EMT samples of both control and GS-NO-treated animals. Noteworthy, in small-size EMT and adjacent tissues of DNIC-treated rats the active form of ribonucleotide reductase and pathological changes were not found.
Assuntos
Endometriose/patologia , Endometriose/prevenção & controle , Glutationa/administração & dosagem , Ferro/administração & dosagem , Óxidos de Nitrogênio/administração & dosagem , S-Nitrosoglutationa/administração & dosagem , Animais , Combinação de Medicamentos , Feminino , Ratos , Ratos Wistar , Resultado do TratamentoRESUMO
This study examines the role of s-nitrosylation in the growth of ovarian cancer using cell culture based and in vivo approaches. Using the nitrosylating agent, S-nitrosoglutathione (GSNO), a physiological nitric oxide molecule, we show that GSNO treatment inhibited proliferation of chemoresponsive and chemoresistant ovarian cancer cell lines (A2780, C200, SKVO3, ID8, OVCAR3, OVCAR4, OVCAR5, OVCAR7, OVCAR8, OVCAR10, PE01 and PE04) in a dose dependent manner. GSNO treatment abrogated growth factor (HB-EGF) induced signal transduction including phosphorylation of Akt, p42/44 and STAT3, which are known to play critical roles in ovarian cancer growth and progression. To examine the therapeutic potential of GSNO in vivo, nude mice bearing intra-peritoneal xenografts of human A2780 ovarian carcinoma cell line (2 × 10(6)) were orally administered GSNO at the dose of 1 mg/kg body weight. Daily oral administration of GSNO significantly attenuated tumor mass (p<0.001) in the peritoneal cavity compared to vehicle (phosphate buffered saline) treated group at 4 weeks. GSNO also potentiated cisplatin mediated tumor toxicity in an A2780 ovarian carcinoma nude mouse model. GSNO's nitrosylating ability was reflected in the induced nitrosylation of various known proteins including NFκB p65, Akt and EGFR. As a novel finding, we observed that GSNO also induced nitrosylation with inverse relationship at tyrosine 705 phosphorylation of STAT3, an established player in chemoresistance and cell proliferation in ovarian cancer and in cancer in general. Overall, our study underlines the significance of S-nitrosylation of key cancer promoting proteins in modulating ovarian cancer and proposes the therapeutic potential of nitrosylating agents (like GSNO) for the treatment of ovarian cancer alone or in combination with chemotherapeutic drugs.