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OBJECTIVES: To investigate the changes in the serum levels of oxidized phospholipids (OxPLs) and endothelial nitric oxide synthase (eNOS) and their association with coronary artery disease (CAL) in children in the acute stage of Kawasaki disease (KD), as well as the clinical significance of OxPLs and eNOS. METHODS: A prospective study was conducted on 95 children in the acute stage of KD (KD group). According to the presence of absence of CAL, the KD group was further divided into a CAL subgroup and a non-CAL (NCAL) subgroup. Thirty children with fever due to lower respiratory tract infection were enrolled as the fever group. Thirty healthy children who underwent physical examination were enrolled as the healthy control group. The above groups were compared in terms of general information and serum levels of OxPLs, eNOS and other laboratory indexes, and the correlation between OxPLs level and eNOS level was analyzed. RESULTS: The KD group had a significantly higher level of OxPLs and a significantly lower level of eNOS compared with the fever group and the healthy control group (P<0.05). After treatment, the children with KD had a significantly decreased OxPLs level and a significantly increased eNOS level (P<0.05). Compared with the NCAL subgroup, the CAL subgroup had a significantly higher level of OxPLs and a significantly lower level of eNOS (P<0.05). Among the children of KD, the level of OxPLs was negatively correlated with that of eNOS (rs=-0.353, P<0.05). CONCLUSIONS: Serum OxPLs and eNOS in the acute stage of KD may be involved in the development of CAL in children with KD, and therefore, they may be used as the biomarkers to predict CAL in these children.
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Síndrome de Linfonodos Mucocutâneos , Óxido Nítrico Sintase Tipo III , Fosfolipídeos , Humanos , Síndrome de Linfonodos Mucocutâneos/sangue , Masculino , Feminino , Óxido Nítrico Sintase Tipo III/sangue , Pré-Escolar , Lactente , Estudos Prospectivos , Doença Aguda , Fosfolipídeos/sangue , Oxirredução , Criança , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/etiologiaRESUMO
Insulin, a critical hormone in the human body, exerts its effects by binding to insulin receptors and regulating various cellular processes. While nitric oxide (NO) plays an important role in insulin secretion and acts as a mediator in the signal transduction pathway between upstream molecules and downstream effectors, holds a significant position in the downstream signal network of insulin. Researches have shown that the insulin-NO system exhibits a dual regulatory effect within the central nervous system, which is crucial in the regulation of diabetic encephalopathy (DE). Understanding this system holds immense practical importance in comprehending the targets of existing drugs and the development of potential therapeutic interventions. This review extensively examines the characterization of insulin, NO, Nitric oxide synthase (NOS), specific NO pathway, their interconnections, and the mechanisms underlying their regulatory effects in DE, providing a reference for new therapeutic targets of DE.
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Nitric oxide synthases (NOSs), a family of flavo-hemoproteins with relatively rigid domains linked by flexible regions, require optimal FMN domain docking to the heme domain for efficient interdomain electron transfer (IET). To probe the FMN-heme interdomain docking, the magnetic dipole interactions between the FMN semiquinone radical (FMNHâ¢) and the low-spin ferric heme centers in oxygenase/FMN (oxyFMN) constructs of neuronal and inducible NOS (nNOS and iNOS, respectively) were measured using the relaxation-induced dipolar modulation enhancement (RIDME) technique. The FMNH⢠RIDME data were analyzed using the mesoscale Monte Carlo calculations of conformational distributions of NOS, which were improved to account for the native degrees of freedom of the amino acid residues constituting the flexible interdomain tethers. This combined computational and experimental analysis allowed for the estimation of the stabilization energies and populations of the docking complexes of calmodulin (CaM) and the FMN domain with the heme domain. Moreover, combining the five-pulse and scaled four-pulse RIDME data into a single trace has significantly reduced the uncertainty in the estimated docking probabilities. The obtained FMN-heme domain docking energies for nNOS and iNOS were similar (-3.8 kcal/mol), in agreement with the high degree of conservation of the FMN-heme domain docking interface between the NOS isoforms. In spite of the similar energetics, the FMN-heme domain docking probabilities in nNOS and iNOS oxyFMN were noticeably different (~ 0.19 and 0.23, respectively), likely due to differences in the lengths of the FMN-heme interdomain tethers and the docking interface topographies. The analysis based on the IET theory and RIDME experiments indicates that the variations in conformational dynamics may account for half of the difference in the FMN-heme IET rates between the two NOS isoforms.
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Glycyrrhiza uralensis is a traditional herbal medicine with significant bioactivity. This study investigated the effect of G. uralensis crude water extract (GU-CWE) on nitric oxide synthase 2 (NOS2) expression during myogenesis. GU-CWE treatment increased myoblast differentiation by downregulating NOS2 and upregulating myogenic regulatory factors (MYOD, MYOG, and MYH). Notably, this effect was supported by an observed decrease in NOS2 expression in the gastrocnemius tissues of mice treated with GU-CWE. In addition, GU-CWE treatment and NOS2 knockdown were associated with reductions in reactive oxygen species levels. We further elucidate the role of the NOS2 gene in myoblast differentiation, demonstrating that its role was expression dependent, being beneficial at low expression but detrimental at high expression. High NOS2 gene expression induced oxidative stress, whereas its low expression impaired myotube formation. These findings highlight that the modulation of NOS2 expression by G. uralensis can potentially be use for managing muscle wasting disorders.
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The purpose of this study was to determine the effect of circulating microvesicles isolated from chronic electronic (e-)cigarette users on cultured human umbilical vein endothelial cell (HUVEC) expression of nuclear factor-κB (NF-κB), cellular cytokine release, phosphorylation of endothelial nitric oxide synthase (eNOS) and NO production. The HUVECs were treated with microvesicles isolated via flow cytometry from nine non-tobacco users (five male and four female; 22 ± 2 years of age) and 10 e-cigarette users (six male and four female; 22 ± 2 years of age). Microvesicles from e-cigarette users induced significantly greater release of interleukin-6 (183.4 ± 23.6 vs. 150.6 ± 15.4 pg/mL; P = 0.002) and interleukin-8 (160.0 ± 31.6 vs. 129.4 ± 11.2 pg/mL; P = 0.01), in addition to expression of p-NF-κB p65 (Ser536) (18.8 ± 3.4 vs. 15.6 ± 1.5 a.u.; P = 0.02) from HUVECs compared with microvesicles from non-tobacco users. Nuclear factor-κB p65 was not significantly different between microvesicles from the non-tobacco users and from the e-cigarette users (87.6 ± 8.7 vs. 90.4 ± 24.6 a.u.; P = 0.701). Neither total eNOS (71.4 ± 21.8 vs. 80.4 ± 24.5 a.u.; P = 0.413) nor p-eNOS (Thr495) (229.2 ± 26.5 vs. 222.1 ± 22.7 a.u.; P = 0.542) was significantly different between microvesicle-treated HUVECs from non-tobacco users and e-cigarette users. However, p-eNOS (Ser1177) (28.9 ± 6.2 vs. 45.8 ± 9.0 a.u.; P < 0.001) expression was significantly lower from e-cigarette users compared with non-tobacco users. Nitric oxide production was significantly lower (8.2 ± 0.6 vs. 9.7 ± 0.9 µmol/L; P = 0.001) in HUVECs treated with microvesicles from e-cigarette users compared with microvesicles from non-tobacco users. This study demonstrated increased NF-κB activation and inflammatory cytokine production, in addition to diminished eNOS activity and NO production resulting from e-cigarette use. HIGHLIGHTS: What is the central question of this study? Circulating microvesicles contribute to cardiovascular health and disease via their effects on the vascular endothelium. The impact of electronic (e-)cigarette use on circulating microvesicle phenotype is not well understood. What is the main finding and its importance? Circulating microvesicles from e-cigarette users increase endothelial cell inflammation and impair endothelial nitric oxide production. Endothelial inflammation and diminished nitric oxide bioavailability are central factors underlying endothelial dysfunction and, in turn, cardiovascular disease risk. Deleterious changes in the functional phenotype of circulating microvesicles might contribute to the reported adverse effects of e-cigarette use on cardiovascular health.
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Nitric oxide (NO) has been defined as the "miracle molecule" due to its essential pleiotropic role in living systems. Besides its implications in physiologic functions, it is also involved in the development of several disease states, and understanding this ambivalence is crucial for medicinal chemists to develop therapeutic strategies that regulate NO production without compromising its beneficial functions in cell physiology. Although nitric oxide synthase (NOS), i.e., the enzyme deputed to the NO biosynthesis, is a well-recognized druggable target to regulate NO bioavailability, some issues have emerged during the past decades, limiting the progress of NOS modulators in clinical trials. In the present review, we discuss the most promising advancements in the research of small molecules that are able to regulate NOS activity with improved pharmacodynamic and pharmacokinetic profiles, providing an updated framework of this research field that could be useful for the design and development of new NOS modulators.
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Inibidores Enzimáticos , Óxido Nítrico Sintase , Óxido Nítrico , Humanos , Óxido Nítrico Sintase/metabolismo , Animais , Óxido Nítrico/metabolismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/uso terapêuticoRESUMO
Avascular necrosis (AVN) is a debilitating condition characterized by bone tissue death due to inadequate blood supply, leading to joint dysfunction and collapse. This study investigates the potential association between AVN and COVID-19, focusing on genetic factors such as NOS3 polymorphisms. A total of 180 individuals were included, comprising 120 COVID-19 patients and 60 healthy controls. Clinical, haematological, biochemical, and genetic parameters were assessed. Results revealed significant differences in respiratory and heart rates, haematological counts, and biochemical markers between AVN and control groups. Genetic analysis showed a higher prevalence of the TG genotype and G allele in NOS3 rs1799983 polymorphism among AVN patients. Additionally, NOS3 rs2070744 polymorphism correlated with various clinical parameters, including blood pressure, heart rate, and haematological indices. This study highlights the potential role of genetic factors in predisposing individuals to AVN following COVID-19 infection.
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COVID-19 , Óxido Nítrico Sintase Tipo III , Osteonecrose , Feminino , Humanos , Masculino , Estudos de Casos e Controles , COVID-19/genética , COVID-19/complicações , COVID-19/patologia , Predisposição Genética para Doença , Genótipo , Óxido Nítrico Sintase Tipo III/genética , Osteonecrose/genética , Polimorfismo de Nucleotídeo ÚnicoRESUMO
A sustained formation of nitric oxide (NO) by endothelial nitric oxide synthase (eNOS) is crucial to safeguard the vascular system against the development of cardiovascular diseases. This study investigated the prolonged phosphorylation and expression of eNOS induced by polyphenol-rich Aronia melanocarpa juice (AMJ), along with its underlying mechanisms. The findings revealed that AMJ triggered concentration- and time-dependent increases in eNOS phosphorylation and expression, leading to sustained NO production for 15 h. Investigations with various enzymes and inhibitors revealed that the effect of AMJ was associated with redox sensitivity, activating the PI3-kinase/Akt, JNK, and p38 MAPK pathways. These pathways led to the inactivation of transcription factors FoxO1 and FoxO3a through phosphorylation, relieving their repression on eNOS expression. Therefore, the capability of AMJ to consistently trigger prolonged eNOS phosphorylation and expression via complex redox-sensitive pathways highlights its potential for maintaining vascular health and preventing cardiovascular diseases.
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Sex differences in immune responses impact cancer outcomes and treatment response, including in glioblastoma (GBM). However, host factors underlying sex specific immune-cancer interactions are poorly understood. Here, we identify the neurotransmitter γ-aminobutyric acid (GABA) as a driver of GBM-promoting immune response in females. We demonstrated that GABA receptor B (GABBR) signaling enhances L-Arginine metabolism and nitric oxide synthase 2 (NOS2) expression in female granulocytic myeloid-derived suppressor cells (gMDSCs). GABBR agonist and GABA analog promoted GBM growth in females in an immune-dependent manner, while GABBR inhibition reduces gMDSC NOS2 production and extends survival only in females. Furthermore, female GBM patients have enriched GABA transcriptional signatures compared to males, and the use of GABA analogs in GBM patients is associated with worse short-term outcomes only in females. Collectively, these results highlight that GABA modulates anti-tumor immune response in a sex-specific manner, supporting future assessment of GABA pathway inhibitors as part of immunotherapy approaches.
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BACKGROUND: The Pro-inflammatory mediators such as prostaglandin E2, nitric oxide and TNF-α are the key players in the stimulation of the inflammatory responses. Thus, the pro-inflammatory mediators are considered to be potential targets for screening nutraceutical with anti-inflammatory activity. METHODS: In this context, we explored the anti-inflammatory potency of seagrass extract with western blot (Bio-Rad) analysis by using LPS induced RAW macrophages as in-vitro models, western blot analysis, In-silico methods using Mastero 13.0 software. RESULTS: The anti-inflammatory activity of Seagrass was demonstrated through down regulation of Pro-inflammatory markers such as Cyclooxygenase-2, induced Nitric oxide synthase and prostaglandin E synthase-1. The results were validated by docking the phytochemical constituents of seagrass namely Isocoumarin, Hexadecanoic acid, and Cis-9 Octadecenoic acid, 1,2 Benzene dicarboxylic acid and beta-sitosterol with TNF-alpha, COX-2, iNOS and PGES-1. CONCLUSION: The methanolic extract of seagrass Halophila beccarii is a potential nutraceutical agent for combating against inflammation with a significant anti-inflammatory activity.
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Anti-Inflamatórios , Suplementos Nutricionais , Extratos Vegetais , Camundongos , Anti-Inflamatórios/farmacologia , Animais , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Células RAW 264.7 , Biomarcadores , Alismatales/química , Inflamação/tratamento farmacológico , Ciclo-Oxigenase 2/metabolismoRESUMO
In plants, nitric oxide (NO) has become a versatile signaling molecule essential for mediating a wide range of physiological processes under various biotic and abiotic stress conditions. The fundamental function of NO under various stress scenarios has led to a paradigm shift in which NO is now seen as both a free radical liberated from the toxic product of oxidative metabolism and an agent that aids in plant sustenance. Numerous studies on NO biology have shown that NO is an important signal for germination, leaf senescence, photosynthesis, plant growth, pollen growth, and other processes. It is implicated in defense responses against pathogensas well as adaptation of plants in response to environmental cues like salinity, drought, and temperature extremes which demonstrates its multifaceted role. NO can carry out its biological action in a variety of ways, including interaction with protein kinases, modifying gene expression, and releasing secondary messengers. In addition to these signaling events, NO may also be in charge of the chromatin modifications, nitration, and S-nitrosylation-induced posttranslational modifications (PTM) of target proteins. Deciphering the molecular mechanism behind its essential function is essential to unravel the regulatory networks controlling the responses of plants to various environmental stimuli. Taking into consideration the versatile role of NO, an effort has been made to interpret its mode of action based on the post-translational modifications and to cover shreds of evidence for increased growth parameters along with an altered gene expression.
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Óxido Nítrico , Plantas , Estresse Fisiológico , Óxido Nítrico/metabolismo , Plantas/metabolismo , Estresse Fisiológico/fisiologia , Transdução de Sinais , Fenômenos Fisiológicos VegetaisRESUMO
Calcific aortic valve disease (CAVD) is prevalent in developed nations and has emerged as a pressing global public health concern due to population aging. The precise etiology of this disease remains uncertain, and recent research has primarily focused on examining the role of valvular interstitial cells (VICs) in the development of CAVD. The predominant treatment options currently available involve open surgery and minimally invasive interventional surgery, with no efficacious pharmacological treatment. This article seeks to provide a comprehensive understanding of valvular endothelial cells (VECs) from the aspects of valvular endothelium-derived nitric oxide (NO), valvular endothelial mechanotransduction, valvular endothelial injury, valvular endothelial-mesenchymal transition (EndMT), and valvular neovascularization, which have received less attention, and aims to establish their role and interaction with VICs in CAVD. The ultimate goal is to provide new perspectives for the investigation of non-invasive treatment options for this disease.
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Estenose da Valva Aórtica , Valva Aórtica , Calcinose , Células Endoteliais , Humanos , Calcinose/patologia , Valva Aórtica/patologia , Valva Aórtica/metabolismo , Células Endoteliais/patologia , Células Endoteliais/metabolismo , Animais , Estenose da Valva Aórtica/patologia , Óxido Nítrico/metabolismo , Mecanotransdução Celular , Valvopatia Aórtica/metabolismo , Valvopatia Aórtica/patologia , Transição Epitelial-MesenquimalRESUMO
INTRODUCTION: The comorbidities of ischemic heart disease (IHD) and diabetes mellitus (DM) compromise the protection of the diabetic heart from ischemia/reperfusion (I/R) injury. We hypothesized that manipulation of reperfusion injury salvage kinase (RISK) and survivor activating factor enhancement (SAFE) pathways might protect the diabetic heart, and intervention of these pathways could be a new avenue for potentially protecting the diabetic heart. METHODS: All hearts were subjected to 30-min ischemia and 30-min reperfusion. During reperfusion, hearts were exposed to molecules proven to protect the heart from I/R injury. The hemodynamic data were collected using suitable software. The infarct size, troponin T levels, and protein levels in hearts were evaluated. RESULTS: Both cyclosporine-A and nitric oxide donor (SNAP) infusion at reperfusion protected 4-week diabetic hearts from I/R injury. However, 6-week diabetic hearts were protected only by SNAP, but not cyclosporin-A. These treatments significantly (p < 0.05) improved cardiac hemodynamics and decreased infarct size. CONCLUSIONS: The administration of SNAP to diabetic hearts protected both 4- and 6-week diabetic hearts; however, cyclosporine-A protected only the 4-week diabetic hearts. The eNOS/GLUT-4 pathway executed the SNAP-mediated cardioprotection.
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Ciclosporina , Diabetes Mellitus Experimental , Traumatismo por Reperfusão Miocárdica , Miocárdio , Doadores de Óxido Nítrico , Óxido Nítrico , Transdução de Sinais , Animais , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Óxido Nítrico/metabolismo , Diabetes Mellitus Experimental/complicações , Masculino , Ciclosporina/farmacologia , Doadores de Óxido Nítrico/farmacologia , Miocárdio/metabolismo , Miocárdio/patologia , Infarto do Miocárdio/patologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/prevenção & controle , Glicemia/metabolismo , Glicemia/efeitos dos fármacos , Fatores de Tempo , Ratos Sprague-Dawley , Troponina T/metabolismo , Hiperglicemia/metabolismo , Hiperglicemia/complicações , Transportador de Glucose Tipo 4RESUMO
BACKGROUND: Folate intake during pregnancy is essential for fetal development and maternal health. However, the specific effects of folic acid (FA) and 5-methyl-(6S)-tetrahydrofolate (5-MTHF) on the prevention and treatment of hypertensive disorders of pregnancy remain unclear. We investigated whether FA and 5-MTHF have different effects on endothelial cell tetrahydrobiopterin (BH4) metabolism in pregnancy and the possible consequences for endothelial NO generation, maternal blood pressure, and fetal growth. METHODS: We analyzed the maternal blood pressure in pregnant wild-type (Gch1fl/fl) and Gch1fl/fl Tie2cre mice treated with either FA or 5-MTHF starting before pregnancy, mid-pregnancy or late pregnancy. BH4, superoxide, and NO bioavailability were determined in mouse and human models of endothelial cell BH4 deficiency by high-performance liquid chromatography. RESULTS: In vitro studies in mouse and human endothelial cells showed that treatment with 5-MTHF, but not FA, elevated BH4 levels, reduced superoxide production, and increased NO synthase activity. In primary endothelial cells isolated from women with hypertensive pregnancies, exposure to 5-MTHF, but not FA, restored the reduction in BH4 levels and NO synthase activity. In vivo studies in mice revealed that oral treatment with 5-MTHF, but not FA, prevented and treated hypertension in pregnancy when administered either before or during pregnancy, respectively, and normalized placental and fetal growth restriction if administered from mid-gestation onward. CONCLUSIONS: Collectively, these studies identify a critical role for 5-MTHF in endothelial cell function in pregnancy, related to endothelial cell BH4 availability and NO synthase activity. Thus, 5-MTHF represents a novel therapeutic agent that may potentially improve endothelial function in hypertensive disorders of pregnancy by targeting endothelial cell BH4.
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Biopterinas , Células Endoteliais , Hipertensão Induzida pela Gravidez , Tetra-Hidrofolatos , Animais , Gravidez , Feminino , Biopterinas/análogos & derivados , Biopterinas/farmacologia , Biopterinas/metabolismo , Camundongos , Hipertensão Induzida pela Gravidez/tratamento farmacológico , Hipertensão Induzida pela Gravidez/metabolismo , Tetra-Hidrofolatos/farmacologia , Tetra-Hidrofolatos/metabolismo , Humanos , Células Endoteliais/metabolismo , Células Endoteliais/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Modelos Animais de Doenças , Ácido Fólico/farmacologia , Ácido Fólico/análogos & derivados , Ácido Fólico/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Óxido Nítrico/metabolismo , Células CultivadasRESUMO
Ventromedial hypothalamic nucleus (VMN) growth hormone-releasing hormone (Ghrh) neurotransmission shapes counterregulatory hormone secretion. Dorsomedial VMN Ghrh neurons express the metabolic-sensitive transcription factor steroidogenic factor-1/NR5A1 (SF-1). In vivo SF-1 gene knockdown tools were used here to address the premise that in male rats, SF-1 may regulate basal and/or hypoglycemic patterns of Ghrh, co-transmitter biosynthetic enzyme, and estrogen receptor (ER) gene expression in these neurons. Single-cell multiplex qPCR analyses showed that SF-1 regulates basal profiles of mRNAs that encode Ghrh and protein markers for neurochemicals that suppress (γ-aminobutyric acid) or enhance (nitric oxide; glutamate) counterregulation. SF-1 siRNA pretreatment respectively exacerbated or blunted hypoglycemia-associated inhibition of glutamate decarboxylase67 (GAD67/GAD1) and -65 (GAD65/GAD2) transcripts. Hypoglycemia augmented or reduced nitric oxide synthase and glutaminase mRNAs, responses that were attenuated by SF-1 gene silencing. Ghrh and Ghrh receptor transcripts were correspondingly refractory to or increased by hypoglycemia, yet SF-1 knockdown decreased both gene profiles. Hypoglycemic inhibition of ER-alpha and G protein-coupled-ER gene expression was amplified by SF-1 siRNA pretreatment, whereas as ER-beta mRNA was amplified. SF-1 knockdown decreased (corticosterone) or elevated [glucagon, growth hormone (GH)] basal counterregulatory hormone profiles, but amplified hypoglycemic hypercorticosteronemia and -glucagonemia or prevented elevated GH release. Outcomes document SF-1 control of VMN Ghrh neuron counterregulatory neurotransmitter and ER gene transcription. SF-1 likely regulates Ghrh nerve cell receptivity to estradiol and release of distinctive neurochemicals during glucose homeostasis and systemic imbalance. VMN Ghrh neurons emerge as a likely substrate for SF-1 control of glucose counterregulation in the male rat.
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Hormônio Liberador de Hormônio do Crescimento , Neurônios , Ratos Sprague-Dawley , Fator Esteroidogênico 1 , Núcleo Hipotalâmico Ventromedial , Animais , Masculino , Hormônio Liberador de Hormônio do Crescimento/metabolismo , Hormônio Liberador de Hormônio do Crescimento/genética , Núcleo Hipotalâmico Ventromedial/metabolismo , Fator Esteroidogênico 1/metabolismo , Fator Esteroidogênico 1/genética , Neurônios/metabolismo , Ratos , Receptores de Estrogênio/metabolismo , Receptores de Estrogênio/genética , Glutamato Descarboxilase/metabolismo , Glutamato Descarboxilase/genética , Regulação da Expressão Gênica , Hipoglicemia/metabolismo , RNA Interferente Pequeno/farmacologiaRESUMO
In response to mechanical loading of bone, osteocytes produce nitric oxide (NOâ¢) and decrease sclerostin protein expression, leading to an increase in bone mass. However, it is unclear whether NO⢠production and sclerostin protein loss are mechanistically linked, and, if so, the nature of their hierarchical relationship within an established mechano-transduction pathway. Prior work showed that following fluid-shear stress (FSS), osteocytes produce NOX2-derived reactive oxygen species, inducing calcium (Ca2+) influx. Increased intracellular Ca2+ results in calcium-calmodulin dependent protein kinase II (CaMKII) activation, which regulates the lysosomal degradation of sclerostin protein. Here, we extend our discoveries, identifying NO⢠as a regulator of sclerostin degradation downstream of mechano-activated CaMKII. Pharmacological inhibition of nitric oxide synthase (NOS) activity in Ocy454 osteocyte-like cells prevented FSS-induced sclerostin protein loss. Conversely, short-term treatment with a NO⢠donor in Ocy454 cells or isolated murine long bones was sufficient to induce the rapid decrease in sclerostin protein abundance, independent of changes in Sost gene expression. Ocy454 cells express all three NOS genes, and transfection with siRNAs targeting eNOS/Nos3 was sufficient to prevent FSS-induced loss of sclerostin protein, while siRNAs targeting iNOS/Nos2 mildly blunted the loss of sclerostin but did not reach statistical significance. Similarly, siRNAs targeting both eNOS/Nos3 and iNOS/Nos2 prevented FSS-induced NO⢠production. Together, these data show iNOS/Nos2 and eNOS/Nos3 are the primary producers of FSS-dependent NOâ¢, and that NO⢠is necessary and sufficient for sclerostin protein control. Further, selective inhibition of elements within this sclerostin-controlling mechano-transduction pathway indicated that NO⢠production occurs downstream of CaMKII activation. Targeting Camk2d and Camk2g with siRNA in Ocy454 cells prevented NO⢠production following FSS, indicating that CaMKII is needed for NO⢠production. However, NO⢠donation (1min) resulted in a significant increase in CaMKII activation, suggesting that NO⢠may have the ability to tune CaMKII response. Together, these data support that CaMKII is necessary for, and may be modulated by NOâ¢, and that the interaction of these two signals is involved in the control of sclerostin protein abundance, consistent with a role in bone anabolic responses.
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Proteínas Adaptadoras de Transdução de Sinal , Óxido Nítrico , Osteócitos , Óxido Nítrico/metabolismo , Animais , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Osteócitos/metabolismo , Camundongos , Estresse Mecânico , Camundongos Endogâmicos C57BL , Mecanotransdução Celular , Linhagem Celular , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismoRESUMO
The present study investigated the neuroprotective properties of whole plants of Grewia bilamellata Gagnep. extract (GBEE) against cerebral ischemia by harnessing both In vivo studies in a rat model and In silico studies focusing on nitric oxide synthase (NOS) inhibition. High-resolution liquid chromatographyâmass spectrometry (HR LCâMS) analysis identified 32 phytochemicals in the GBEE, 15 of which adhered to Lipinski's rule of five. These compounds exhibited diverse physicochemical properties and high binding affinity to NOS, with cleomiscosin D showing the greatest potential. In vivo, GBEE had significant neuroprotective effects on bilateral common carotid artery occlusion/reperfusion (BCCAO/R) in rats, especially at doses of 200 mg/kg and 400 mg/kg body weight. GBEE treatment improved brain function, as evidenced by EEG normalization, substantial reductions in cerebral infarction size, mitigated neuronal loss, and the restoration of regular histological arrangement in the CA1 hippocampal area of the brain. Furthermore, GBEE enhanced antioxidant defenses by augmenting the activity of catalase (CAT) and superoxide dismutase (SOD), reducing malondialdehyde (MDA) levels, and restoring reduced glutathione (GSH) levels. These effects were accompanied by a decrease in nitric oxide (NO) levels, indicative of attenuated oxidative and nitrosative stress. Collectively, our findings suggest that GBEE is a promising natural therapeutic agent that may prevent or alleviate ischemic brain injury through a multifaceted mechanism involving NOS inhibition and attenuation of the oxidative stress response. This study highlights the therapeutic potential of GBEE and warrants further research into its mechanism of action and possible clinical applications.
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BACKGROUND: Hypertension is a major risk factor for cardiovascular diseases. Peristrophe bivalvis (PB) is used for the treatment of hypertension, painful sprains, skin diseases, tuberculosis, acute bronchitis, anti-inflammatory conditions, hepatitis, and diabetes. Its antihypertensive potential has been investigated and documented. This study investigated the antihypertensive mechanism of aqueous extract of PB leaf (APB) on L-NAME-induced hypertension. METHODS: Thirty male wistar rats (150-170 g) were grouped into five (n=5). Group 1 received 10 mL/kg of distilled water (control), while groups 2-5 were administered 60 mg/kg of L-NAME (L-- NAME60) orally for eight weeks to induce hypertension. After eight weeks, groups 2-5 received L-NAME60+distilled water (HNT), distilled water (HRE), L-NAME60+APB (200 mg/kg, [HAPB]), and L-NAME60+ramipril (10 mg/kg, [HRA]), respectively, for five weeks. The BP was measured by the tail-cuff method. The blood sample was obtained under anesthesia, and tissue samples were obtained after euthanasia. Serum renin, ACE, angiotensin-II, endothelin-1, and cyclic guanosine monophosphate (cGMP) levels were measured using ELISA techniques. Malondialdehyde, superoxide dismutase (SOD), and reduced glutathione (GSH) levels were measured by spectrophotometry. Data were analyzed using ANOVA at α0.05. RESULTS: The BP significantly decreased in HAPB compared to HNT. Renin, ACE, and angiotensin-II levels significantly decreased while cGMP levels increased in the HAPB group compared to HNT. Malondialdehyde levels significantly decreased, and SOD and GSH levels increased compared to HNT. CONCLUSION: Peristrophe bivalvis aqueous leaf extract reduced blood pressure in hypertensive rats by modulating the cGMP signalling pathway and the renin-angiotensin system.
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High-grade gliomas (HGG) comprising WHO grades 3 and 4 have a poor overall survival (OS) that has not improved in the past decade. Herein, markers representing four components of the tumor microenvironment (TME) were identified to define their linked expression in TME and predict the prognosis in HGG, namely, interleukin6 (IL6, inflammation), inducible nitric oxide synthase(iNOS), heat shock protein-70 (HSP70, hypoxia), vascular endothelial growth receptor (VEGF), and endothelin1 (ET1) (angiogenesis) and matrix metalloprotease-14 (MMP14) and intercellular adhesion molecule1 (ICAM1, extracellular matrix). To establish a non-invasive panel of biomarkers for precise prognostication in HGG. Eighty-six therapy-naive HGG patients with 45 controls were analyzed for the defined panel. Systemic expression of extracellular/secretory biomarkers was screened dot-immune assay (DIA), quantified by ELISA, and validated by immunocytochemistry (ICC). Expression of iNOS, HSP70, IL-6, VEGF, ET1, MMP14, and ICAM1 was found to be positively associated with grade. Quantification of circulating levels of the markers by ELISA and ICC presented a similar result. The biomarkers were observed to negatively correlate with OS (p < 0.0001). Cox-regression analysis yielded all biomarkers as good prognostic indicators and independent of confounders. On applying combination statistics, the biomarker panel achieved higher sensitivity than single markers to define survival. The intra-association of all seven biomarkers was significant, hinting of a cross-talk between the TME components and a hypoxia driven systemic inflammation upregulating the expression of other components. This is a first ever experimental study of a marker panel that can distinguish between histopathological grades and also delineate differential survival using liquid biopsy, suggesting that markers of hypoxia can be a cornerstone for personalized therapy. The panel of biomarkers of iNOS, HSP70, IL-6, VEGF, ET1, MMP14, and ICAM1 holds promise for prognostication in HGG.
Assuntos
Biomarcadores Tumorais , Neoplasias Encefálicas , Glioma , Proteínas de Choque Térmico HSP70 , Neovascularização Patológica , Óxido Nítrico Sintase Tipo II , Microambiente Tumoral , Humanos , Glioma/metabolismo , Glioma/patologia , Feminino , Masculino , Pessoa de Meia-Idade , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP70/sangue , Biomarcadores Tumorais/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Adulto , Neovascularização Patológica/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Molécula 1 de Adesão Intercelular/sangue , Interleucina-6/metabolismo , Interleucina-6/sangue , Metaloproteinase 14 da Matriz/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/sangue , Endotelina-1/metabolismo , Endotelina-1/sangue , Idoso , Hipóxia Tumoral , Prognóstico , AngiogêneseRESUMO
BACKGROUND: Several medications, including antihistamines, can alter salivary gland function, causing dry mouth or xerostomia. Antihistamines are commonly used for treating allergic rhinitis. OBJECTIVES: The aim of the present study was to compare and correlate the effects of first-generation vs. second-generation H1-antihistamines on the parotid glands of rats. MATERIAL AND METHODS: Twelve adult male albino rats were used; 4 rats served as a control group (group I) and the remaining rats were divided into 2 groups: group II received promethazine hydrochloride; and group III received cetirizine dihydrochloride for 3 weeks. The parotid salivary glands were dissected, and examined histologically and analyzed histomorphometrically for the acinar area percentage. In addition, mRNA gene expression of iNOS, caspase-3 and α-SMA was assessed using quantitative realtime polymerase chain reaction (qRT-PCR). Finally, all the obtained data was statistically analyzed. RESULTS: Histologically, group I showed the typical architecture of the gland. In group II, degenerative changes were noticed, including acinar degeneration and shrinkage with widened connective tissue septa, intracellular vacuolization, and increased inflammatory cell infiltration. In group III, similar histological features were detected as in group II, but to a lesser extent. Histomorphometric results revealed significant differences in the acinar area percentage between various groups. In addition, qRT-PCR results showed a significant increase in iNOS expression in both groups II and III as compared to group I, caspase-3 gene expression was significantly increased in group II, while in group III, it increased non-significantly. Finally, α-SMA gene expression non-significantly decreased in both groups II and III. A significant positive correlation was observed between caspase-3 and iNOS gene expression, while an inverse correlation was noticed between caspase-3 and α-SMA gene expression. CONCLUSIONS: The administration of antihistamines resulted in changes in the rat salivary glands, which could be due to the induction of oxidative stress and the resultant apoptotic effect. These changes were suggested to occur mainly through action on muscarinic receptors; yet, action on histamine receptors could not be excluded. However; these effects were less marked with the second-generation antihistamine.