RESUMO
ABSTRACT: Oxidative stress, the renin-angiotensin system (RAS), and inflammation are some of the mechanisms involved in the pathogenesis of hypertension. The aim of this study is to examine the protective effect of the chronic administration of astaxanthin, which is extracted from the shell of crabs and shrimps, into hypothalamic paraventricular nucleus (PVN) in spontaneously hypertensive rats. Animals were randomly assigned to 2 groups and treated with bilateral PVN infusion of astaxanthin or vehicle (artificial cerebrospinal fluid) through osmotic minipumps (Alzet Osmotic Pumps, Model 2004, 0.25 µL/h) for 4 weeks. Spontaneously hypertensive rats had higher mean arterial pressure and plasma level of norepinephrine and proinflammatory cytokine; higher PVN levels of reactive oxygen species, NOX2, NOX4, IL-1ß, IL-6, ACE, and AT1-R; and lower PVN levels of IL-10 and Cu/Zn SOD, Mn SOD, ACE2, and Mas receptors than Wistar-Kyoto rats. Our data showed that chronic administration of astaxanthin into PVN attenuated the overexpression of reactive oxygen species, NOX2, NOX4, inflammatory cytokines, and components of RAS within the PVN and suppressed hypertension. The present results revealed that astaxanthin played a role in the brain. Our findings demonstrated that astaxanthin had protective effect on hypertension by improving the balance between inflammatory cytokines and components of RAS.
Assuntos
Anti-Inflamatórios/administração & dosagem , Anti-Hipertensivos/administração & dosagem , Pressão Arterial/efeitos dos fármacos , Citocinas/metabolismo , Hipertensão/tratamento farmacológico , Mediadores da Inflamação/metabolismo , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Sistema Renina-Angiotensina/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Infusões Parenterais , Masculino , Núcleo Hipotalâmico Paraventricular/metabolismo , Núcleo Hipotalâmico Paraventricular/fisiopatologia , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Fatores de Tempo , Xantofilas/administração & dosagemRESUMO
Exercise training is one of the major non-pharmacological treatments for hypertension. However, the central mechanism by which exercise training attenuates the hypertensive responses remains unclear. Irisin is a muscle-secreted cytokine derived from fibronectin type III domain containing 5 (FNDC5) that will be released into the circulation during exercise. We hypothesized that irisin may play a role in the blood pressure regulation by exercise. To examine the hypothesis, our study investigated the effect of irisin on hypertension and its central mechanism. The study was performed in spontaneously hypertensive rats (SHRs) and normotensive Wistar-Kyoto rats. We found that intravenous injection of irisin effectively reduced blood pressure, plasma norepinephrine, paraventricular nucleus (PVN) levels of neuronal activation, oxidative stress and inflammation in SHRs. Moreover, irisin activated nuclear factor E2-related factor-2 (Nrf2) and restored the imbalance of neurotransmitters in the PVN. Our study also found PVN knockdown of Nrf2 abolished the protective effects of irisin on hypertension. These findings demonstrate irisin can improve hypertension via Nrf2-mediated antioxidant in the PVN.
Assuntos
Anti-Hipertensivos/farmacologia , Fibronectinas/farmacologia , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Citocinas/metabolismo , Neurotransmissores/metabolismo , Norepinefrina/sangue , Estresse Oxidativo/efeitos dos fármacos , Esforço Físico , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKYRESUMO
Oxidative stress induced by long-term cyclosporine A (CsA) administration is a major cause of chronic nephrotoxicity, which is characterized by tubular atrophy, tubular cell apoptosis, and interstitial fibrosis in the progression of organ transplantation. Although hydrogen-rich water (HRW) has been used to prevent various oxidative stress-related diseases, its underlying mechanisms remain unclear. This study investigated the effects of HRW on CsA-induced nephrotoxicity and its potential mechanisms. After administration of CsA (25 mg/kg/day), rats were treated with or without HRW (12 mL/kg) for 4 weeks. Renal function and vascular activity were investigated. Histological changes in kidney tissues were analyzed using Masson's trichrome and terminal deoxynucleotidyl transferase dUTP nick-end labeling stains. Oxidative stress markers and the activation of the Kelch-like ECH-associated protein 1 (Keap1)/nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway were also measured. We found that CsA increased the levels of reactive oxygen species (ROS) and malonaldehyde (MDA), but it reduced glutathione (GSH) and superoxide dismutase (SOD) levels. Such alterations induced vascular dysfunction, tubular atrophy, interstitial fibrosis, and tubular apoptosis. This was evident secondary to an increase in urinary protein, serum creatinine, and blood urea nitrogen, ultimately leading to renal dysfunction. Conversely, HRW decreased levels of ROS and MDA while increasing the activity of GSH and SOD. This was accompanied by an improvement in vascular and renal function. Moreover, HRW significantly decreased the level of Keap1 and increased the expression of Nrf2, NADPH dehydrogenase quinone 1, and heme oxygenase 1. In conclusion, HRW restored the balance of redox status, suppressed oxidative stress damage, and improved kidney function induced by CsA via activation of the Keap1/Nrf2 signaling pathway.
Assuntos
Ciclosporina/efeitos adversos , Hidrogênio/farmacologia , Imunossupressores/efeitos adversos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Substâncias Protetoras/farmacologia , Insuficiência Renal/induzido quimicamente , Transdução de Sinais/efeitos dos fármacos , Água/farmacologia , Animais , Apoptose/efeitos dos fármacos , Nitrogênio da Ureia Sanguínea , Creatinina/sangue , Creatinina/urina , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Insuficiência Renal/urina , Superóxido Dismutase/metabolismo , Água/químicaRESUMO
Docosahexaenoic acid (DHA) is reported to have the potential to ameliorate pulmonary arterial hypertension (PAH), while the specific mechanism is still obscure. This study aims to investigate the function of DHA in pulmonary artery smooth muscle cells (PASMCs) and explore the underlying mechanism. In our study, DHA was used to incubate PASMCs. Cytosolic-free Ca2+ concentration ([Ca2+ ]cyt) was measured using Fluo-3 AM method. Real-time polymerase chain reaction was used to detect microRNA-16 (miR-16) and calcium-sensing receptor (CaSR) messenger RNA expression levels. CCK-8 assay, BrdU assay, and Transwell assay were employed to detect the effects of DHA on proliferation and migration of PASMCs. CaSR was confirmed as a direct target of miR-16 using dual-luciferase assay, polymerase chain reaction, and Western blot analysis. It was found that DHA significantly inhibited PASMC proliferation and migration and decreased [Ca2+ ]cyt. After transfection of miR-16 mimics, proliferation and migration ability of PASMCs were significantly inhibited, whereas opposite effects were observed after miR-16 inhibition. [Ca2+ ]cyt was also inhibited by miR-16 transfection. DHA then promoted the expression of miR-16, and the effects of DHA on PASMCs were annulled when miR-16 was inhibited. CaSR was identified as a direct target of miR-16. CaSR was inhibited directly by miR-16 and indirectly by DHA. In conclusion, DHA inhibits the proliferation and migration of PASMCs, and probably ameliorates PAH via regulating miR-16/CaSR axis.
Assuntos
Cálcio/metabolismo , Regulação para Baixo/efeitos dos fármacos , MicroRNAs/metabolismo , Músculo Liso/efeitos dos fármacos , Artéria Pulmonar/efeitos dos fármacos , Receptores de Detecção de Cálcio/metabolismo , Sítios de Ligação , Células Cultivadas , Ácidos Docosa-Hexaenoicos/farmacologia , Humanos , Transporte de Íons , Músculo Liso/citologia , Músculo Liso/metabolismo , Artéria Pulmonar/citologia , Artéria Pulmonar/metabolismoRESUMO
Although the distribution of progestagens in aquatic environments has been widely reported, details on their uptake, elimination, and biotransformation in fish have received little attention. This study investigated the uptake, elimination, and biotransformation potential of a progestagen, cyproterone acetate (CPTA), in Nile tilapia ( Oreochromis niloticus) exposed to an environmentally relevant concentration under semistatic regimes. CPTA in tilapia tissues followed a similar pattern, reaching a concentration plateau within 4 days of exposure, and dropping to below limits of quantitation within 4 days of elimination. The calculated steady-state bioconcentration factors suggest a low bioconcentration potential of CPTA in juvenile tilapia. Results of enzymatic hydrolysis treatments revealed that no conjugates of CPTA were present in tissues, but conjugated biotransformation products of CPTA were found in bile, liver, and muscle. Most CPTA entered tissues and then was biotransformed into seven different products by phase I and phase II metabolism. The concentrations of endogenous cortisol were significantly influenced by CPTA in plasma and liver during the uptake period. These findings suggest that biotransformation products of CPTA should be considered for the assessment of the bioconcentration potential and ecological effects of progestagens.
Assuntos
Tilápia , Poluentes Químicos da Água , Animais , Biotransformação , Acetato de Ciproterona , ProgestinasRESUMO
Obesity, a major contributor to the development of cardiovascular diseases, is associated with an autonomic imbalance characterized by sympathetic hyperactivity and diminished vagal activity. Vagal activation plays important roles in weight loss and improvement of cardiac function. Pyridostigmine is a reversible acetylcholinesterase inhibitor, but whether it ameliorates cardiac lipid accumulation and cardiac remodeling in rats fed a high-fat diet has not been determined. This study investigated the effects of pyridostigmine on high-fat diet-induced cardiac dysfunction and explored the potential mechanisms. Rats were fed a normal or high-fat diet and treated with pyridostigmine. Vagal discharge was evaluated using the BL-420S system, and cardiac function by echocardiograms. Lipid deposition and cardiac remodeling were determined histologically. Lipid utility was assessed by qPCR. A high-fat diet led to a significant reduction in vagal discharge and lipid utility and a marked increase in lipid accumulation, cardiac remodeling, and cardiac dysfunction. Pyridostigmine improved vagal activity and lipid metabolism disorder and cardiac remodeling, accompanied by an improvement of cardiac function in high-fat diet-fed rats. An increase in the browning of white adipose tissue in pyridostigmine-treated rats was also observed and linked to the expression of UCP-1 and CIDEA. Additionally, pyridostigmine facilitated activation of brown adipose tissue via activation of the SIRT-1/AMPK/PGC-1α pathway. In conclusion, a high-fat diet resulted in cardiac lipid accumulation, cardiac remodeling, and a significant decrease in vagal discharge. Pyridostigmine ameliorated cardiomyopathy, an effect related to reduced cardiac lipid accumulation, and facilitated the browning of white adipose tissue while activating brown adipose tissue.
Assuntos
Tecido Adiposo/metabolismo , Cardiomiopatias/prevenção & controle , Gorduras na Dieta/efeitos adversos , Brometo de Piridostigmina/farmacologia , Nervo Vago/fisiopatologia , Tecido Adiposo/patologia , Tecido Adiposo/fisiopatologia , Animais , Cardiomiopatias/metabolismo , Cardiomiopatias/patologia , Cardiomiopatias/fisiopatologia , Gorduras na Dieta/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Proteínas Musculares/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Nervo Vago/metabolismo , Nervo Vago/patologiaRESUMO
Cardiac hypertrophy is associated with autonomic imbalance, characterized by enhanced sympathetic activity and withdrawal of parasympathetic control. Increased parasympathetic function improves ventricular performance. However, whether pyridostigmine, a reversible acetylcholinesterase inhibitor, can offset cardiac hypertrophy induced by pressure overload remains unclear. Hence, this study aimed to determine whether pyridostigmine can ameliorate pressure overload-induced cardiac hypertrophy and identify the underlying mechanisms. Rats were subjected to either sham or constriction of abdominal aorta surgery and treated with or without pyridostigmine for 8 weeks. Vagal activity and cardiac function were determined using PowerLab. Cardiac hypertrophy was evaluated using various histological stains. Protein markers for cardiac hypertrophy were quantitated by Western blot and immunoprecipitation. Pressure overload resulted in a marked reduction in vagal discharge and a profound increase in cardiac hypertrophy index and cardiac dysfunction. Pyridostigmine increased the acetylcholine levels by inhibiting acetylcholinesterase in rats with pressure overload. Pyridostigmine significantly attenuated cardiac hypertrophy based on reduction in left ventricular weight/body weight, suppression of the levels of atrial natriuretic peptide, brain natriuretic peptide and ß-myosin heavy chain, and a reduction in cardiac fibrosis. These effects were accompanied by marked improvement of cardiac function. Additionally, pyridostigmine inhibited the CaN/NFAT3/GATA4 pathway and suppressed Orai1/STIM1 complex formation. In conclusion, pressure overload resulted in cardiac hypertrophy, cardiac dysfunction and a significant reduction in vagal discharge. Pyridostigmine attenuated cardiac hypertrophy and improved cardiac function, which was related to improved cholinergic transmission efficiency (decreased acetylcholinesterase and increased acetylcholine), inhibition of the CaN/NFAT3/GATA4 pathway and suppression of the interaction of Orai1/STIM1.
Assuntos
Calcineurina/metabolismo , Cardiomegalia/tratamento farmacológico , Cardiomegalia/metabolismo , Pressão , Brometo de Piridostigmina/administração & dosagem , Brometo de Piridostigmina/uso terapêutico , Transdução de Sinais , Animais , Cardiomegalia/diagnóstico por imagem , Cardiomegalia/fisiopatologia , Fator de Transcrição GATA4/metabolismo , Testes de Função Cardíaca , Hemodinâmica/efeitos dos fármacos , Masculino , Fatores de Transcrição NFATC/metabolismo , Proteína ORAI1/metabolismo , Ligação Proteica/efeitos dos fármacos , Ratos Sprague-Dawley , Molécula 1 de Interação Estromal/metabolismo , Fatores de Tempo , Nervo Vago/efeitos dos fármacos , Nervo Vago/patologiaRESUMO
It is well-accepted that inflammation plays an important role in the development of cardiac remodelling and that therapeutic approaches targeting inflammation can inhibit cardiac remodelling. Although a large amount of evidence indicates that activation of α7 nicotinic acetylcholine receptor (α7nAChR) causes an anti-inflammatory effect, the role of α7nAChR in cardiac remodelling and the underlying mechanism have not been established. To investigate the effect of the specific α7nAChR agonist, PNU282987, on cardiac remodelling induced by isoproterenol (ISO 60 mg/kg per day) in mice, the cardiomyocyte cross-sectional area (CSA) and collagen volume fraction were evaluated by hematoxylin and eosin (HE) and Masson staining, respectively. Cardiac function and ventricular wall thickness were measured by echocardiography. The protein expressions of collagen I, matrix metalloproteinase 9 (MMP-9), transforming growth factor ß1 (TGF-ß1), and Smad3 were analyzed by Western blot. ISO-induced cardiac hypertrophy, characterized by an increase in the heart weight/body weight ratio, CSA and ventricular wall thickness. Moreover, cardiac fibrosis indices, such as collagen volume fraction, MMP-9 and collagen I protein expression, were also increased by ISO. PNU282987 not only attenuated cardiac hypertrophy but also decreased the cardiac fibrosis induced by ISO. Furthermore, PNU282987 suppressed TGF-ß1 protein expression and the phosphorylation of Smad3 induced by ISO. In conclusion, PNU282987 ameliorated the cardiac remodelling induced by ISO, which may be related to the TGF-ß1/Smad3 pathway. These data imply that the α7nAChR may represent a novel therapeutic target for cardiac remodelling in many cardiovascular diseases.
Assuntos
Benzamidas/uso terapêutico , Compostos Bicíclicos com Pontes/uso terapêutico , Cardiomegalia/tratamento farmacológico , Agonistas Nicotínicos/uso terapêutico , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Remodelação Ventricular/efeitos dos fármacos , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Animais , Benzamidas/administração & dosagem , Compostos Bicíclicos com Pontes/administração & dosagem , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Isoproterenol/farmacologia , Masculino , Camundongos Endogâmicos BALB C , Miocárdio/metabolismo , Miocárdio/patologia , Agonistas Nicotínicos/administração & dosagem , Transdução de SinaisRESUMO
Previous findings from our laboratory and others indicate that the main therapeutic effect of angiotensin II type 1 receptor (AT1-R) antagonists is to decrease blood pressure and exert anti-inflammatory effects in the cardiovascular system. In this study, we determined whether AT1-R antagonist telmisartan within the hypothalamic paraventricular nucleus (PVN) attenuates hypertension and hypothalamic inflammation via both the TLR4/MyD88/NF-κB signaling pathway and peroxisome proliferator-activated receptor-γ (PPAR-γ) in the PVN in hypertensive rats. Spontaneously hypertensive rats (SHR) and normotensive Wistar Kyoto (WKY) rats were treated for 4weeks through bilateral PVN infusion with the AT1-R antagonist telmisartan (TEL, 10µg/h), or losartan (LOS, 20µg/h), or the PPAR-γ antagonist GW9662 (GW, 100µg/h), or vehicle via osmotic minipump. Mean arterial pressure (MAP) was recorded by a tail-cuff occlusion method. PVN tissue and blood were collected for the measurement of AT1-R, PPAR-γ, pro-inflammatory cytokines (tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6), inducible nitric oxide synthase (iNOS), TLR4, MyD88, nuclear factor-kappa B (NF-κB) activity and plasma norepinephrine (NE), respectively. Hypertensive rats exhibited significantly higher level of AT1-R and lower level of PPAR-γ in the PVN. PVN treatment with TEL attenuated MAP, improved cardiac hypertrophy, reduced TNF-α, IL-1ß, IL-6, iNOS levels, and plasma NE in SHR but not in WKY rats. These results were associated with reduced TLR4, MyD88 and NF-κB levels and increased PPAR-γ level in the PVN of hypertensive rats. Our findings suggest that TLR4/MyD88/NF-κB signaling and PPAR-γ within the PVN are involved in the beneficial effects of telmisartan in hypertension.
Assuntos
Anti-Hipertensivos/farmacologia , Benzimidazóis/farmacologia , Benzoatos/farmacologia , Hipertensão/metabolismo , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Animais , Pressão Arterial/efeitos dos fármacos , Cardiomegalia/sangue , Cardiomegalia/metabolismo , Citocinas/sangue , Citocinas/genética , Citocinas/metabolismo , Hipertensão/sangue , Masculino , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Norepinefrina/sangue , PPAR gama/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Transdução de Sinais/efeitos dos fármacos , Telmisartan , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismoRESUMO
Previous findings have shown that acetylcholine (ACh) decreased hypoxia-induced tumor necrosis factor alpha (TNF α) production, thus protected against cardiomyocyte injury. However, whether and how ACh affects TNF α-induced endoplasmic reticulum (ER) stress and cell apoptosis remain poorly defined. This study was aimed at determining the effect of ACh in H9c2 cells after TNF α stimulation. Presence of ER stress was verified using the ER stress protein markers glucose regulatory protein 78 (GRP78) and C/EBP homologous protein (CHOP). Cell apoptosis was shown by caspase-3 activation and terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling. Exogenously administered ACh significantly decreased these TNF α-induced changes. Moreover, when the cells were exposed to nonspecific muscarinic receptor (M AChR) inhibitor atropine, methoctramine (M2 AChR inhibitor) or the epidermal growth factor receptor (EGFR) inhibitor AG1478, the cardioprotection elicited by ACh was diminished. Furthermore, the above effects were also blocked by M2 AChR or EGFR siRNA, indicating that EGFR transactivation by M2 AChR may be the major pathway responsible for the benefits of ACh. In addition, LY294002, a phosphatidylinositol-3-kinase (PI3K) inhibitor, displayed the similar trends as AG1478, suggesting that PI3K/Akt signaling may be the downstream of EGFR in ACh-elicited anti-apoptotic property. Together, these data indicate that EGFR-PI3K/Akt signaling is involved in M2 AChR-mediated ER apoptotic pathway suppression and the subsequent survival of H9c2 cardiomyocytes. We have identified a novel pathway underlying the cardioprotection afforded by ACh.
Assuntos
Apoptose , Retículo Endoplasmático/metabolismo , Receptores ErbB/metabolismo , Miócitos Cardíacos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Acetilcolina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Cromonas/farmacologia , Retículo Endoplasmático/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Morfolinas/farmacologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Ratos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologiaRESUMO
BACKGROUND: Excessive activation of matrix metalloproteinase 9 (MMP-9) has been found in several inflammatory diseases. Previous studies have shown that acetylcholine (ACh) reduced the levels of pro-inflammatory cytokines and decreased tissue damage. Therefore, this study was designed to explore the potential effects and mechanisms of ACh on MMP-9 production and cell migration in response to lipopolysaccharide (LPS) stimulation in RAW264.7 cells. METHODS: MMP-9 expression and activity were induced by LPS in RAW264.7 cells, and examined by real-time PCR, western blotting and gelatin zymography, respectively. ELISA was used to determine the changes in MMP-9 secretion among the groups. Macrophage migration was evaluated using transwell migration assay. Knockdown of α7 nicotinic acetylcholine receptor (α7 nAChR) expression was performed using siRNA transfection. RESULTS: Pre-treatment with ACh inhibited LPS-induced MMP-9 production and macrophage migration in RAW264.7 cells. These effects were abolished by the α7 nAChR antagonist methyllycaconitine (MLA) and α7 nAChR siRNA. The α7 nAChR agonist PNU282987 was found to have an effect similar to that of ACh. Moreover, ACh enhanced the expression of JAK2 and STAT3, and the JAK2 inhibitor AG490 and the STAT3 inhibitor static restored the effect of ACh. Meanwhile, ACh decreased the phosphorylation and nuclear translocation of NF-κB, and this effect was abrogated in the presence of MLA. In addition, the JAK2 and STAT3 inhibitor abolished the inhibitory effects of ACh on phosphorylation of NF-κB. CONCLUSIONS: Activation of α7 nAChR by ACh inhibited LPS-induced MMP-9 production and macrophage migration through the JAK2/STAT3 signaling pathway. These results provide novel insights into the anti-inflammatory effects and mechanisms of ACh.
Assuntos
Acetilcolina/farmacologia , Movimento Celular/efeitos dos fármacos , Janus Quinase 2/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Metaloproteinase 9 da Matriz/biossíntese , Fator de Transcrição STAT3/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Animais , Linhagem Celular , Macrófagos/enzimologia , Macrófagos/metabolismo , CamundongosRESUMO
To study the chemical constituents of the inflorescences of Coreopsis tinctoria from Xinjiang, isolation and purification of constituents were carried out by column chromatography on macroporous resin (D101) , MCI gel, MDS gel, silica gel, Sephadex LH-20 and semi-preparative HPLC. The structures of the compounds were identified by physicchemical properties and spectral data analysis. Fourteen compounds were isolated and identified as coretinterpenoid A (1), coretinphenol (2), quercetin (3), quercetin-3-O-ß-glucopyranoside (4), luteolin (5), taxifolin (6), 7, 3', 5'-trihydroxyflavanone (7), isookanin (8), isookanin-7-O-ß-D-glucopyranoside (9), 5, 7, 3', 5'-tetrahydroxyflavanone-7-O-ß-D-glucopyranoside (10), butein (11), okanin (12), sulfuretin (13), and linocinnamarin (14). Compound 1 was a new isabolane-type sesquiterpenoid and compounds 4, 10 and 13 were isolated from this plant for the first time.
Assuntos
Coreopsis/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/químicaRESUMO
Autonomic imbalance characterized by sympathetic predominance coinciding with diminished vagal activity is an independent risk factor in cardiovascular diseases. Several studies show that vagus nerve stimulation exerted beneficial effects on cardiac function and survival. In this study, we investigated the vagomimetic effect of pyridostigmine on left ventricular (LV) remodeling in rats after myocardial infarction. After myocardial infarction, surviving rats were treated with or without pyridostigmine (31 mg·kg⻹·d⻹) for 2 weeks, and hemodynamic parameters were measured. LV tissue was used to assess infarct size and interstitial fibrosis by Masson's trichrome and 0.1% picrosirius red staining. Protein expression of heart tissues was used to assess the efficacy of the treatment. Pyridostigmine markedly reduced myocardial infarct size and improved cardiac diastolic function. These improvements were accompanied with a significant decrease in matrix metalloproteinase-2 expression and collagen deposition. Additionally, pyridostigmine inhibited both transforming growth factor-ß1 (TGF-ß1) and TGF-ß1-activated kinase expression in hearts postmyocardial infarction. Thus, pyridostigmine reduces collagen deposition, attenuates cardiac fibrosis, and improves LV diastolic function after myocardial infarction via TGF-ß1/TGF-ß1-activated kinase pathway inhibition.
Assuntos
Inibidores da Colinesterase/uso terapêutico , MAP Quinase Quinase Quinases/antagonistas & inibidores , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/patologia , Brometo de Piridostigmina/uso terapêutico , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Remodelação Ventricular/efeitos dos fármacos , Animais , Fibrose , Hemodinâmica/efeitos dos fármacos , Hidroxiprolina/metabolismo , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Infarto do Miocárdio/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacosRESUMO
The field of small-molecule inhibitors of protein-protein interactions is rapidly advancing and the specific area of inhibitors of the p53/MDM2 interaction is a prime example. Several groups have published on this topic and multiple compounds are in various stages of clinical development. Building on the strength of the discovery of RG7112, a Nutlin imidazoline-based compound, and RG7388, a pyrrolidine-based compound, we have developed additional scaffolds that provide opportunities for future development. Here, we report the discovery and optimization of a highly potent and selective series of spiroindolinone small-molecule MDM2 inhibitors, culminating in RO8994.
Assuntos
Indóis/química , Indolizidinas/química , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Compostos de Espiro/química , Apoptose/efeitos dos fármacos , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Humanos , Imidazolinas/química , Indóis/uso terapêutico , Indóis/toxicidade , Indolizidinas/uso terapêutico , Indolizidinas/toxicidade , Simulação de Dinâmica Molecular , Neoplasias/tratamento farmacológico , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Pirrolidinas/química , Compostos de Espiro/uso terapêutico , Compostos de Espiro/toxicidade , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/metabolismo , para-Aminobenzoatos/químicaRESUMO
Activation of the renin-angiotensin system (RAS) triggers oxidative stress and an inflammatory response in the hypothalamic paraventricular nucleus (PVN), in turn increasing the sympathetic hyperactivity that is a major cause of hypertension. Pyridostigmine has cardioprotective effects by suppressing the RAS of myocardial tissue. However, whether pyridostigmine attenuates hypertension by inhibiting the RAS of the PVN remains unclear. We thus investigated the effect and mechanism of pyridostigmine on two-kidney one-clip (2K1C)-induced hypertension. 2K1C rats received pyridostigmine, or not, for 8 weeks. Cardiovascular function, hemodynamic parameters, and autonomic activity were measured. The PVN levels of pro-/anti-inflammatory cytokines, oxidative stress, and RAS signaling molecules were evaluated. Our results showed that hypertension was accompanied by cardiovascular dysfunction and an autonomic imbalance characterized by enhanced sympathetic but diminished vagal activity. The PVN levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), reactive oxygen species (ROS), NOX-2, and malondialdehyde (MDA) increased; those of IL-10 and superoxide dismutase (SOD) decreased. Moreover, the RAS signaling pathway was activated, as evidenced by increased levels of the angiotensin-converting enzyme (ACE), angiotensin II (Ang II), and the Ang II type 1 receptor (AT1R) and a decreased AT2R level. Pyridostigmine lowered blood pressure and improved cardiovascular function, associated with restoration of the autonomic balance. Meanwhile, pyridostigmine decreased PVN IL-6, TNF-α, ROS, NOX-2, and MDA levels and increased IL-10 and SOD levels. Additionally, pyridostigmine suppressed PVN ACE, Ang II, and AT1R levels and increased AT2R expression. Pyridostigmine attenuated hypertension by inhibiting PVN oxidative stress and inflammation induced by the RAS.
RESUMO
BACKGROUND: Acetylcholine (ACh), a neurotransmitter of vagal nerve, offers tolerance to ischemia/reperfusion injury. Given the regulation of autophagy in cardioprotection, this study was to examine the role of autophagy in ACh-elicited protection against hypoxia/reoxygenation (HR) injury. METHODS: H9c2 cells were subjected to HR injury. Autophagy was determined by transmission electron microscopy, MDC staining and western blot. MTT kit, LDH and CK release, ATP content and TUNEL assay were used to evaluate cardiomyocytes injury. Atg7 and AMPK knockdown was performed with siRNA transfection. RESULTS: Following 4, 8, 12 and 16 h reoxygenation, autophagosomes were decreased along with reduced cell viability. ACh during 4 h reoxygenation facilitated autophagy as evidence by increased autophagosomes and MDC labeling autophagic vacuoles. H9c2 cells treated with ACh also underwent a biochemical changes by increased ratio of LC3-II/LC3-I and autophagy flux (decreased p62), while muscarinic receptor antagonist atropine suppressed these effects. Induction of autophagy was correlated with enhanced cell survival and decreased apoptosis. Autophagy inhibition with chloroquine and Atg7 siRNA significantly attenuated ACh-induced cytoprotection. ACh-elicited autophagy activation could be related to increased AMPK phosphorylation and decreased mTOR phosphorylation. AMPK siRNA exhibited an elevation in mTOR phosphorylation and reduced the ratio of LC3-II/LC3-I. Importantly, AMPK knockdown desensitized H9c2 cells to ACh-mediated protection. CONCLUSIONS: These data provided first evidence that ACh-induced autophagy elicited cytoprotective effects through muscarinic receptor activated-AMPK-mTOR pathway, and suggested a novel mechanism of ACh-induced tolerance against HR injury.
Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Acetilcolina/farmacologia , Autofagia/efeitos dos fármacos , Hipóxia Celular , Citoproteção/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Proteínas Quinases Ativadas por AMP/genética , Animais , Atropina/farmacologia , Proteína 7 Relacionada à Autofagia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cloroquina/farmacologia , Proteínas Associadas aos Microtúbulos/metabolismo , Antagonistas Muscarínicos/farmacologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Fosforilação/efeitos dos fármacos , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ratos , Receptores Muscarínicos/química , Receptores Muscarínicos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Enzimas Ativadoras de Ubiquitina/antagonistas & inibidores , Enzimas Ativadoras de Ubiquitina/genética , Enzimas Ativadoras de Ubiquitina/metabolismoRESUMO
The physiological activities of the mammalian heart are regulated by the autonomic nervous system. An imbalanced autonomic nervous system with increased sympathetic tone and reduced vagal tone has been implicated in cardiovascular diseases. Experimental and clinical reports have demonstrated that vagal nerve activation is able to improve outcomes for multiple cardiovascular diseases, such as ischaemic heart disease, heart failure, arrhythmia and hypertension. In this paper, we mainly focus on the potential cardioprotective mechanisms of vagal nerve activation. Based on the knowledge gained from our experiments and other published reports, vagal activation results in cardioprotection is not only associated with heart rate, anti-adrenergic effect but also related to anti-inflammatory activity, regulation of cellular redox states and regulation of mitochondrial targets. In conclusion, vagal nerve activation may be a promising new therapeutic approach for the treatment of cardiovascular diseases.
Assuntos
Doenças Cardiovasculares/fisiopatologia , Doenças Cardiovasculares/terapia , Nervo Vago/fisiopatologia , Animais , Sistema Nervoso Autônomo/fisiopatologia , Humanos , Inflamação/patologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/fisiologia , Oxirredução , Receptores Colinérgicos/fisiologiaRESUMO
The role of celecoxib in cardiovascular events remains contentious. The aim of the present study was to investigate the effects of celecoxib in acute myocardial ischaemia (AMI) in rabbits in comparison with those of another non-steroidal anti-inflammatory drug, namely aspirin. Male New Zealand white rabbits were divided into four groups: (i) a sham-operated group; (ii) an AMI group, in which the left anterior descending coronary arteries were occluded for 60 min; (iii) the celecoxib + AMI group, pretreated with 3 mg/kg celecoxib, twice a day, for 3 days before AMI induction; and (iv) the aspirin + AMI group, pretreated with 12.5 mg/kg aspirin, twice a day, for 3 days before AMI induction. Haemodynamic parameters were monitored using a multichannel physiological recorder. Serum levels of creatine kinase (CK), malondialdehyde (MDA), cyclo-oxygenase-2 (COX-2), tumour necrosis factor (TNF)-α, total nitrate/nitrite (NO(x) ), nitric oxide synthase (NOS) and myocardial infarct size were determined. Changes in isometric tension of isolated coronary rings were recorded by a myograph system. Compared with the sham group, the AMI group had lower blood pressure, higher left ventricular (LV) end-diastolic pressure, depressed maximum dP/dt of LV pressure, a larger infarct size and higher CK and MDA levels. Celecoxib, but not aspirin, pretreatment significantly ameliorated these effects of AMI. Celecoxib reversed AMI-induced increases in COX-2 levels to a similar extent as aspirin. Pretreatment with celecoxib resulted in a significant reduction in TNF-α levels and an increase in NO(x) and NOS levels compared with the AMI group. The dysfunctional vasoconstriction and vasodilation of coronary arteries were ameliorated by celecoxib administration. 4. In conclusion, the experimental evidence suggests that celecoxib exerts its protective effects in a COX-independent manner.
Assuntos
Vasos Coronários/efeitos dos fármacos , Vasos Coronários/fisiologia , Inibidores de Ciclo-Oxigenase 2/administração & dosagem , Isquemia Miocárdica/tratamento farmacológico , Isquemia Miocárdica/fisiopatologia , Pirazóis/administração & dosagem , Sulfonamidas/administração & dosagem , Doença Aguda , Animais , Celecoxib , Vasos Coronários/enzimologia , Relação Dose-Resposta a Droga , Masculino , Isquemia Miocárdica/enzimologia , Coelhos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologiaRESUMO
Reactive oxygen species (ROS) production is an important mechanism in myocardial ischemia and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is one of major sources of ROS in the heart. Previous studies showed that vagus nerve stimulation (VNS) is beneficial in treating ischemic heart diseases. However, the effect of VNS on ROS production remains elusive. In this study, we investigated the role of VNS onischemia-induced ROS production. Our results demonstrated that VNS alleviated the myocardial injury, attenuated the cardiac dysfunction, reserved the antioxidant enzyme activity and inhibited the formation of ROS as evidenced by the decreased NADPH oxidase (Nox) activity and superoxide fluorescence intensity as well as the expression of p67phox, Rac1 and nitrotyrosine. Furthermore, VNS resulted in the phosphorylation and activation of adenosine monophosphate activated protein kinase (AMPK), which in turn led to an inactivation of Nox by protein kinase C (PKC); however, the phenomena were repressed by the administration of a muscarinic antagonist atropine. Taken together, these data indicate that VNS decreases ROS via AMPK-PKC-Nox pathway; this may have potential importance for the treatment of ischemic heart diseases.
Assuntos
Circulação Coronária , Coração/fisiopatologia , Isquemia/metabolismo , Isquemia/fisiopatologia , Miocárdio/metabolismo , Estresse Oxidativo , Estimulação do Nervo Vago , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Análise Química do Sangue , Pressão Sanguínea , Frequência Cardíaca , Hemodinâmica , Isquemia/sangue , Masculino , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/fisiopatologia , NADP/metabolismo , Oxidantes/sangue , Oxirredução , Proteína Quinase C/metabolismo , Ratos , Transdução de SinaisRESUMO
Background: Shufeng Jiedu (SFJD) capsules can be used as adjunctive treatment for patients with community-acquired pneumonia, but the effectiveness and safety of SFJD are not clear. This review aims to evaluate the effectiveness and safety of SFJD based on randomized controlled trials (RCTs). Methods: A systematic review was conducted by searching PubMed, Embase, Scopus, Web of Science, CENTRAL, CNKI, VIP, CBM, Wanfang and trial registry platforms from their inception to March 2022. Two reviewers screened studies, extracted the data and assessed risk of bias independently. The data were pooled for meta-analysis or presented narratively. Results: Seventeen RCTs involving 1840 participants were included. All trials compared SFJD plus antibiotics to antibiotics, or combined with symptomatic treatment in both groups. The overall certainty of evidence was assessed as moderate to very low certainty. Compared with routine treatment (antibiotics alone or antibiotics plus symptomatic treatment), SFJD plus routine treatment showed beneficial effects in resolution of fever (MD -1.20 days, 95%CI -1.73 to -0.67; 10 RCTs; very low certainty), cough (MD -1.02 days, 95%CI -1.23 to -0.81; 9 RCTs; moderate certainty), phlegm (MD -1.46 days, 95%CI -2.84 to -0.08; 6 RCTs; very low certainty), pulmonary crepitations (MD -1.61 days, 95%CI -2.64 to -0.59; 8 RCTs; low certainty), shortness of breath (MD -2.80 days, 95%CI -2.88 to -2.72; 2 RCTs; low certainty) and chest pain (MD -2.85 days, 95%CI -3.01 to -2.69; 1 RCT; low certainty). There was no significant difference in pathogen clearance (1 RCT). No serious adverse events were reported, but 2.60% (5/192) patients reported nausea in the SFJD groups, 1.04% (2/192) participants in routine group, and no significant difference was identified. Conclusions: Current evidence suggests that adding SFJD may shorten the duration of symptom relief in community-acquired pneumonia for 1-2 days. The adverse events were minor and controllable, and no serious adverse events were reported. Well-reported trials and potential of reducing antibiotics were expected in the future studies.