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Nitric oxide (•NO), a diffusible free radical, is an intercellular messenger, playing a crucial role in several key brain physiological processes, including in neurovascular coupling (NVC). In the brain, glutamatergic activation of the neuronal nitric oxide synthase (nNOS) enzyme constitutes its main synthesis pathway. However, when oxygen (O2) supply is compromised, such as in stroke, ischemia, and aging, such •NO production pathway may be seriously impaired. In this context, evidence suggests that, as already observed in the gastric compartment, the reduction of nitrite by dietary compounds (such as ascorbate and polyphenols) or by specific enzymes may occur in the brain, constituting an important rescuing or complementary mechanism of •NO production. Here, using microsensors selective for •NO, we show that nitrite enhanced the •NO production in a concentration-dependent manner and in the presence of ascorbate evoked by N-methyl-D-aspartate (NMDA) and glutamate stimulation of rat hippocampal slices. Additionally, nitrite potentiated the •NO production induced by oxygen-glucose deprivation (OGD). Overall, these observations support the notion of a redox interaction of ascorbate with nitrite yielding •NO upon neuronal glutamatergic activation and given the critical role of NO as the direct mediator of neurovascular coupling may represents a key physiological mechanism by which •NO production for cerebral blood flow (CBF) responses to neuronal activation is sustained under hypoxic/acidic conditions in the brain.

茉莉花（マツリカ、Jasminum sambac）は、アラビアからインドにかけて分布するモクセイ科の熱帯性常緑低木である。乾燥した花は香りが強く、食品、化粧品に利用されるとともに、伝統医学において下痢、発熱、結膜炎などの治療に用いられている。我々はメディシナルフラワーの機能性解析研究を行っており、スクリーニングの結果から、茉莉花の花部エキス（JSFE）が、リポポリサッカライド（LPS）刺激マウスマクロファージ様RAW264 細胞においてプロスタグランジンE２（PGE２）および一酸化窒素（NO）を抑制することを見出した。そこで本研究では、JSFEの抗炎症作用を解明することを目的として、活性成分の単離・同定を行った。まずJSFEを水に懸濁後、ヘキサン、ジクロロメタン、酢酸エチル、ブタノールで順次分画し、各分画のPGE2 および NO 抑制能を調べたところ、酢酸エチル画分が毒性を示さずPGE２および NO を顕著に抑制した。さらに各種クロマトグラフィーを繰り返すことで、酢酸エチル画分から quercetin (1)、kaempferol (2)、benzyl β-D-glucopyranoside (3)を単離同定した。1-3のうち、1および2はPGE２および NO を抑制し、その作用は1の方が強かった。一方、3は抑制作用を示さなかった。これらの結果より、1および2が JSFE の抗炎症作用に寄与することが示唆された。, Jasminum sambac (L.) Aiton, commonly known as Arabian jasmine, is a small shrub with fragrant and white flowers that is native to India. The flowers are used in various applications such as cosmetics, food, and folk medicine. In our preliminary screening of medicinal flowers, a methanolic extract of J. sambac flower (JSFE) was found to inhibit prostaglandin E2 (PGE2) and nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated murine macrophage-like RAW264 cells. This study aimed to isolate active compounds having anti-inflammatory potential from JSFE. To identify the active compounds that suppress PGE2 and NO production, JSFE was suspended in water and successively partitioned using hexane, dichloromethane (CH2Cl2), ethyl acetate (EtOAc), and n-butanol (n-BuOH). Comparative analysis revealed that the EtOAc fraction inhibited PGE2 and NO production without causing cytotoxicity. Bioassay-guided separation of the EtOAc fraction isolated three compounds: quercetin (1), kaempferol (2), and benzyl β-D-glucopyranoside (3). Among the isolated compounds, 1 and 2 inhibited PGE2 and NO production without causing cytotoxicity, and the inhibitory potency of 1 was higher than that of 2. In contrast, 3 did not show significant inhibition. These results suggest that 1 and 2 can be attributed to the anti-inflammatory potential of JSFE.

OBJECTIVES The mitochondrial adenosine triphosphate-sensitive potassium channel is central to pharmacologically induced tolerance to spinal cord injury. We hypothesized that both direct and nitric oxide-dependent indirect activation of the adenosine triphosphate-sensitive potassium channel contribute to the induction of ischemic metabolic tolerance. METHODS Spinal cord injury was induced in adult male C57BL/6 mice through 7 minutes of thoracic aortic crossclamping. Pretreatment consisted of intraperitoneal injection 3 consecutive days before injury. Experimental groups were sham (no pretreatment or ischemia, n = 10), spinal cord injury control (pretreatment with normal saline, n = 27), Nicorandil 1.0 mg/kg (direct and indirect adenosine triphosphate-sensitive potassium channel opener, n = 20), Nicorandil 1 mg/kg + carboxy-PTIO 1 mg/kg (nitric oxide scavenger, n = 21), carboxy-PTIO (n = 12), diazoxide 5 mg/kg (selective direct adenosine triphosphate-sensitive potassium channel opener, n = 25), and DZ 5 mg/kg+ carboxy-PTIO 1 mg/kg, carboxy-PTIO (n = 23). Limb motor function was assessed using the Basso Mouse Score (0-9) at 12-hour intervals for 48 hours after ischemia. RESULTS Motor function was significantly preserved at all time points after ischemia in the Nicorandil pretreatment group compared with ischemic control. The addition of carboxy-PTIO partially attenuated Nicorandil's motor-preserving effect. Motor function in the Nicorandil + carboxy-PTIO group was significantly preserved compared with the spinal cord injury control group (P

Background/Aim: The inflammatory response plays an important role in the activation and progression of many inflammation-related diseases. Cannabis sativa and Morinda citrifolia have long been used in folk medicine to treat inflammation. Cannabidiol is the most abundant non-psychoactive phytocannabinoid in C. sativa and exhibits anti-inflammatory activity. The objective of this study was to examine the anti-inflammatory effect of cannabidiol in combination with M. citrifolia and compare its effects with those of cannabidiol alone. Materials and Methods: RAW264 cells stimulated with lipopolysaccharide (200 ng/ml) were treated with cannabidiol (0-10 μM), M. citrifolia seed extract (0-100 μg/ml), or a combination of both for 8 or 24 h. Following the treatments, nitric oxide production in the activated RAW264 cells and the expression of inducible nitric oxide synthase were assessed. Results: Our results showed that combination of cannabidiol (2.5 μM) and M. citrifolia seed extract (100 μg/ml) exhibited more efficient inhibition of nitric oxide production than cannabidiol treatment alone in lipopolysaccharide-stimulated RAW264 cells. The combination treatment also reduced the expression of inducible nitric oxide synthase. Conclusion: These results suggest that the anti-inflammatory effect of combined treatment with cannabidiol and M. citrifolia seed extract causes a reduction in the expression of inflammatory mediators., This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY-NC-ND) 4.0 international license (https://creativecommons.org/licenses/by-nc-nd/4.0).

Over the past 30 years, the significance of nitric oxide (NO) has become increasingly apparent in mammalian physiology. It is biosynthesized by three isoforms of nitric oxide synthases (NOS): neuronal (nNOS), endothelial (eNOS), and inducible (iNOS). Neuronal and eNOS both produce low levels of NO (nM) as a signaling agent and vasodilator, respectively. Inducible (iNOS) is present in activated macrophages at sites of infection to generate acutely toxic (μM) levels of NO as part of the mammalian immune defense mechanism. These discoveries have led to numerous animal and clinical studies to evaluate the potential therapeutic utility of NO in various medical operations/treatments, primarily using NO gas (via gas-cylinders) as the NO source. In this review, we focus specifically on recent advances in the electrochemical generation of NO (E-NOgen) as an alternative means to generate NO from cheap and inert sources, and the fabrication and testing of biomedical devices that utilize E-NOgen to controllably generate NO for medical applications.

Introduction: Perioperative alterations in perfusion lead to ischemia and reperfusion injury, and supplemental oxygen is administered during surgery to limit hypoxic injury but can lead to hyperoxia. We hypothesized that hyperoxia impairs endothelium-dependent and endothelium-independent vasodilation but not the vasodilatory response to heme-independent soluble guanylyl cyclase activation. Methods: We measured the effect of oxygen on vascular reactivity in mouse aortas. Mice were ventilated with 21% (normoxia), 60% (moderate hyperoxia), or 100% (severe hyperoxia) oxygen during 30 minutes of renal ischemia and 30 minutes of reperfusion. After sacrifice, the thoracic aorta was isolated, and segments mounted on a wire myograph. We measured endothelium-dependent and endothelium-independent vasodilation with escalating concentrations of acetylcholine (ACh) and sodium nitroprusside (SNP), respectively, and we measured the response to heme-independent soluble guanylyl cyclase activation with cinaciguat. Vasodilator responses to each agonist were quantified as the maximal theoretical response ( Emax ) and the effective concentration to elicit 50% relaxation (EC 50 ) using a sigmoid model and nonlinear mixed-effects regression. Aortic superoxide was measured with dihydroethidium probe and high-performance liquid chromatography quantification of the specific superoxide product 2-hydroxyethidium. Results: Hyperoxia impaired endothelium-dependent (ACh) and endothelium-independent (SNP) vasodilation compared with normoxia and had no effect on cinaciguat-induced vasodilation. The median ACh Emax was 76.4% (95% confidence interval = 69.6 to 83.3) in the normoxia group, 53.5% (46.7 to 60.3) in the moderate hyperoxia group, and 53.1% (46.3 to 60.0) in the severe hyperoxia group ( Plt; 0.001, effect across groups), while the ACh EC 50 was not different among groups. The SNP Emax was 133.1% (122.9 to 143.3) in normoxia, 128.3% (118.1 to 138.6) in moderate hyperoxia, and 114.8% (104.6 to 125.0) in severe hyperoxia ( Plt; 0.001, effect across groups), and the SNP EC 50 was 0.38 log M greater in moderate hyperoxia than in normoxia (95% confidence interval = 0.18 to 0.58, Plt; 0.001). Cinaciguat Emax and EC 50 were not different among oxygen treatment groups (median range Emax = 78.0% to 79.4% and EC 50 = -18.0 to -18.2 log M across oxygen groups). Aorta 2-hydroxyethidium was 1419 pmol/mg of protein (25th-75th percentile = 1178-1513) in normoxia, 1993 (1831-2473) in moderate hyperoxia, and 2078 (1936-2922) in severe hyperoxia ( P = 0.008, effect across groups). Conclusions: Hyperoxia, compared with normoxia, impaired endothelium-dependent and endothelium-independent vasodilation but not the response to heme-independent soluble guanylyl cyclase activation, and hyperoxia increased vascular superoxide production. Results from this study could have important implications for patients receiving high concentrations of oxygen and at risk for ischemia reperfusion-mediated organ injury.

Necrotizing enterocolitis (NEC) remains a devastating disease that affects preterm infants. Hydrogen sulfide (H2S) donors have been shown to reduce the severity of NEC, but the optimal compound has yet to be identified. We hypothesized that oral H2S-Mesalamine (ATB-429) would improve outcomes in experimental NEC, and its benefits would be dependent on endothelial nitric oxide synthase (eNOS) pathways. NEC was induced in 5-day-old wild-type (WT) and eNOS knockout (eNOSKO) pups by formula feeding and stress. Four groups were studied in both WT and eNOSKO mice: 1) breastfed controls, 2) NEC, 3) NEC + 50 mg/kg mesalamine, and 4) NEC + 130 mg/kg ATB-429. Mesalamine and ATB-429 doses were equimolar. Pups were monitored for sickness scores and perfusion to the gut was measured by Laser Doppler Imaging (LDI). After euthanasia of the pups, intestine and lung were hematoxylin and eosin-stained and scored for injury in a blind fashion. TLR4 expression was quantified by Western blot and IL-6 expression by ELISA. P < 0.05 was significant. Both WT and eNOSKO breastfed controls underwent normal development and demonstrated milder intestinal and pulmonary injury compared with NEC groups. For the WT groups, ATB-429 significantly improved weight gain, reduced clinical sickness score, and improved perfusion compared with the NEC group. In addition, WT ATB-429 pups had a significantly milder intestinal and pulmonary histologic injury when compared with NEC. ATB-429 attenuated the increase in TLR4 and IL-6 expression in the intestine. When the experiment was repeated in eNOSKO pups, ATB-429 offered no benefit in weight gain, sickness scores, perfusion, intestinal injury, pulmonary injury, or decreasing intestinal inflammatory markers. An H2S derivative of mesalamine improves outcomes in experimental NEC. Protective effects appear to be mediated through eNOS. Further research is warranted to explore whether ATB-429 may be an effective oral therapy to combat NEC.

The birch tree-derived pentacyclic lupine type-triterpenoid Betulinic acid has demonstrated a variety of biological activities BetA is known for its harmlessness on normal healthy cells. However, recent investigations have indicated that BetA can cause cellular changes in mouse normal embryonic fibroblasts even with a minimal concentration. This report cautioned the use of BetA at the clinical level, which encouraged us to examine whether BetA could produce any key effect on normal healthy cells of any organs in mice. The present study extended its investigation to evaluate whether BetA could induce any changes in the renal system and the expression pattern of NADPH-diaphorase an indirect marker of the enzyme nitric oxide synthase in mice. Our results indicated that BetA exposure induced NADPH-d expression in both organs without causing any significant morphological changes. Moreover, NADPH-d activity patterns in the organs of BetA-treated animals tremendously increased (from day 4 until day 12) when compared to controls. The expression of NADPH-d in both the kidney and bladder implies that NADPH-d-mediated nitric oxide signaling could be a mechanism involved in BetA-induced nephroprotection. These outcomes are of direct clinical importance and could pay the way for the improvement of BetA as an important pharmaceutical product.

Hypothalamic paraventricular nucleus (PVN) is an important central site for the control of the adipose afferent reflex (AAR) that increases sympathetic outflow and blood pressure in obesity-related hypertension (OH).In this study, we investigated the effects of nitric oxide (NO) and cardiovascular bioactive polypeptide adrenomedullin (ADM) in the PVN on AAR and sympathetic nerve activity (SNA) in OH rats induced by a high-fat diet.The results showed that ADM, total neuronal NO synthase (nNOS) and phosphorylated-nNOS protein expression levels in the PVN of the OH rats were down-regulated compared to the control rats. The enhanced AAR in OH rats was attenuated by PVN acute application of NO donor sodium nitroprusside (SNP), but was strengthened by the nNOS inhibitor nNOS-I, guanylyl cyclase inhibitor (1H-[1,2,4]Oxadiazolo[4,3-a]quinoxalin-1-one, ODQ) and gamma-aminobutyric acid A type receptor (GABAA) antagonist Bicuculline. Moreover, PVN ADM microinjection not only decreased basal SNA but also attenuated the enhanced AAR in OH rats, which were effectively inhibited by ADM receptor antagonist ADM22-52, nNOS-I, ODQ or Bicuculline pretreatment. Bilateral PVN acute microinjection of ADM also caused greater increases in NO and cyclic guanosine monophosphate (cGMP) levels, and nNOS phosphorylation. Adeno-associated virus vectors encoding ADM (AAV-ADM) transfection in the PVN of OH rats not only decreased the elevated AAR, basal SNA and blood pressure (BP), but also increased the expression and activation of nNOS. Furthermore, AAV-ADM transfection improved vascular remodeling in OH rats.Taken together, our data highlight the roles of ADM in improving sympathetic overactivation, enhanced AAR and hypertension, and its related mechanisms associated with receptors mediated NO-cGMP-GABAA pathway in OH condition.

Nitric oxide (NO) participates in processes such as endothelium-dependent vasodilation and neurotransmission/neuromodulation. The role of NO in epilepsy is controversial, attributing it to anticonvulsant but also proconvulsant properties. Clarification of this dual effect of NO might lead to the development of new antiepileptic drugs. Previous results in our laboratory indicated that this contradictory role of NO in seizures could depend on the nitric oxide synthase (NOS) isoform involved, which could play opposite roles in epileptogenesis, one of them being proconvulsant but the other anticonvulsant. The effect of convulsant drugs on neuronal NO (nNO) and endothelial NO (eNO) levels was investigated. Considering the distribution of neuronal and endothelial NOS in neurons and astrocytes, resp., primary cultures of neurons and astrocytes were used as a study model. The effects of convulsant drugs pentylenetetrazole, thiosemicarbazide, 4-aminopyridine and bicuculline on NO levels were studied, using a spectrophotometric method. Their effects on NO levels in neurons and astrocytes depend on the concentration and time of treatment. These convulsant drugs caused an increase in nNO, but a decrease in eNO was proportional to the duration of treatment in both cases. Apparently, nNO possesses convulsant properties mediated by its effect on the glutamatergic and GABAergic systems, probably through GABAA receptors. Anticonvulsant properties of eNO may be the consequence of its effect on endothelial vasodilation and its capability to induce angiogenesis. Described effects last as seizures do. Considering the limitations of these kinds of studies and the unexplored influence of inducible NO, further investigations are required.

News. - Beet juice has recently become the focus of interest of many research entities. This is due to its positive effects on many aspects of exercise in various sports disciplines. Supplementation with nitrate-rich beet juice can both reduce muscle soreness and accelerate the recovery process, reduce the aerobic cost of exercise, and improve the physical performance of athletes. Nitrate supplementation increases plasma nitrite concentrations and lowers resting blood pressure. Furthermore, nitrate supplementation also lowers the aerobic cost during submaximal exercise and may, under certain circumstances, increase exercise tolerance and performance. This is due to the increased bioavailability of nitric oxide. Nitric oxide is a gaseous signaling molecule that modulates physiological functions in the human body. It affects blood flow, muscle contractility, mitochondrial respiration, glucose homeostasis, immune function, and is a neurotransmitter. The form of administration of beet juice concentrate affects plasma nitrate and nitrite levels and the time to reach their peak values. It seems that beet juice supplementation will benefit amateurs more than professionals with high maximal oxygen consumption (VO2max) levels. Prospect and projects. - Thus, it seems reasonable to use beet juice in athletes participating in team sports characterized by high-intensity intermittent activity. This paper aims to review studies on the effects of beet juice in different sports.

The low permeability of antifungal agents to fungal biofilms, which allows the continued survival of the fungus inside, is a key issue that makes fungal infections difficult to cure. Inspired by the unique dynamic molecule motion properties of the polyrotaxane (PR) nanomedicine, herein, a dynamic delivery system Clo@mPRP/NONOate was fabricated by co-loading nitric oxide (NO) and the antifungal drug clotrimazole (Clo) onto the α-cyclodextrin (α-CD) PR modified mesoporous polydopamine (mPDA) nanoparticles, in which pentaethylenehexamine (PEHA) was grafted to α-CDs. The cationic α-CDs endowed this dynamic NO/Clo codelivery system with the ability to effectively attach to fungal biofilms through electrostatic interaction, while the introduction of PRs with flexible molecule motion (slide and rotation of CDs) enhanced the permeability of nanoparticles to biofilms. Meanwhile, NO could effectively inhibit the formation of fungal hyphae, showing an dissipating effect on mature biofilms, and could be further combined with Clo to completely eradicate fungi inside the biofilms. In addition, the dynamic system Clo@mPRP/NONOate could efficiently and synergistically eliminate planktonic Candida albicans (C. albicans) in a safe and no toxic side effect manner, and effectively cured C. albicans-induced vaginal infection in mice. Therefore, this dynamic NO/Clo codelivery system provided an effective solution to the clinical treatment of C. albicans-induced vaginal infection, and the application prospect could even be extended to other microbial infectious diseases. STATEMENT OF SIGNIFICANCE: A dynamic codelivery system based on cationized cyclodextrin polyrotaxane combining nitric oxide and antifungal drugs clotrimazole was prepared to deal with the issue of clinical fungal biofilm infection. This dynamic codelivery system could be attached to the Candida albicans biofilms and penetrate into biofilm via flexible molecular mobility to effectively eradicate the fungi. This dynamic codelivery system could synergistically and efficiently eliminate planktonic-state Candida albicans, but did not show significant cytotoxicity to normal somatic cells.

Objectives: The aim of this study was to determine the effects of whey proteins on methotrexate (MTX)-induced brain and small intestine damage. Materials and Methods: 30 Sprague Dawley rats (200-300 g) were divided into four groups: Control, control + whey, MTX, and MTX+whey. MTX was administered at 20 mg/kg (single dose) intraperitoneally to the MTX group rats, and 2 mg/kg of whey protein were administered by oral gavage for 10 days to the whey groups. Lipid peroxidation, glutathione, and nitric oxide (NO) levels, as well as glutathione-Stransferase and superoxide dismutase activities were measured in the brain and small intestine. SDS-polyacrylamide gel electrophoresis of the brain and intestine tissues were also carried out. Results: While MTX treatment caused oxidative damage in the brain and small intestine, whey protein administration ameliorated MTXinduced oxidative stress. MTX administration did not change the brain’s NO level, while an increase in intestinal NO level was detected. Conclusion: MTX induced oxidative stress in the brain and small intestine changed the protein metabolism in these tissues regardless of reduced food intake. Consecutive 10-day administration of whey proteins has shown its therapeutic effect on MTX-induced brain and small intestine oxidative damage

Anesthesia with propofol is frequently associated with hypotension. The TRPA1 gene contributes to the vasodilator effect of propofol. Hypotension is crucial for anesthesiologists because it is deleterious in the perioperative period. We tested whether the TRPA1 gene polymorphisms or haplotypes interfere with the hypotensive responses to propofol. PCR-determined genotypes and haplotype frequencies were estimated. Nitrite, nitrates, and NOx levels were measured. Propofol induced a more expressive lowering of the blood pressure (BP) without changing nitrite or nitrate levels in patients carrying CG+GG genotypes for the rs16937976 TRPA1 polymorphism and AG+AA genotypes for the rs13218757 TRPA1 polymorphism. The CGA haplotype presented the most remarkable drop in BP. Heart rate values were not impacted. The present exploratory analysis suggests that TRPA1 genotypes and haplotypes influence the hypotensive responses to propofol. The mechanisms involved are probably other than those related to NO bioavailability. With better genetic knowledge, planning anesthesia with fewer side effects may be possible.

Drought is a serious challenge that causes significant crop loss worldwide. The developmental processes of plants are regulated by phytohormones and signaling molecules that crosstalk together in signaling cascades. We suppose that nitric oxide (NO) is a secondary messenger of the JAs signaling pathway, as 10−7 M methyl jasmonate (MeJA) pretreatment regulates NO accumulation in wheat plants under drought stress, modulated by 12% polyethylene glycol (PEG), and in control plants. This study aimed to compare 2 × 10−4 M nitric oxide donor sodium nitroprusside (SNP) and MeJA pretreatments in regulating growth and water balance parameters at the vulnerable initial first-leaf stage of wheat growth. The application of 12% PEG decreased transpiration intensity twofold, relative water content (RWC) by 7–9%, and osmotic potential of cell sap by 33–40% compared with those of control plants. Under drought, MeJA- and SNP-pretreated plants decreased transpiration intensity by 20–25%, RWC by 3–4%, and osmotic potential of cell sap by 16–21% compared with those of control plants, and enhanced the proline content by 25–55% compared with MeJA- and SNP-untreated plants. Our results suggest that pretreatment with MeJA as well as SNP could mitigate drought stress in wheat plants. Similarities in MeJA- and SNP-induced shifts in plant water balance suggested that NO is a mediator of MeJA-induced regulation of wheat water content during water deficit.

Background: Neurovascular coupling (NVC) is a key process in cerebral blood flow regulation. NVC ensures adequate brain perfusion to changes in local metabolic demands. Neuronal nitric oxide synthase (nNOS) is suspected to be involved in NVC; however, this has not been tested in humans. Our objective was to investigate the effects of nNOS inhibition on NVC in humans. Methods: We performed a 3-visit partially randomized, double-blinded, placebo-controlled, crossover study in 12 healthy subjects. On each visit, subjects received an intravenous infusion of either S-methyl-L-thiocitrulline (a selective nNOS-inhibitor), 0.9% saline (placebo control), or phenylephrine (pressor control). The NVC assessment involved eliciting posterior circulation hyperemia through visual stimulation while measuring posterior and middle cerebral arteries blood velocity. Results: nNOS inhibition blunted the rapidity of the NVC response versus pressor control, evidenced by a reduced initial rise in mean posterior cerebral artery velocity (−3.3% [−6.5, −0.01], P =0.049), and a reduced rate of increase (ie, acceleration) in posterior cerebral artery velocity (slope reduced −4.3% [−8.5, −0.1], P =0.045). The overall magnitude of posterior cerebral artery response relative to placebo control or pressor control was not affected. Changes in BP parameters were well-matched between the S-methyl-L-thiocitrulline and pressor control arms. Conclusions: Neuronal NOS plays a role in dynamic cerebral blood flow control in healthy adults, particularly the rapidity of the NVC response to visual stimulation. This work opens the way to further investigation of the role of nNOS in conditions of impaired NVC, potentially revealing a therapeutic target.

Nitric oxide (NO) is a relevant molecule for vascular homeostasis. The level of serum NO metabolites (NOx), which consist of nitrite and nitrate, has been investigated as an alternative biomarker of NO production, but its clinical value has not yet been determined.143 patients (66 ± 12 years old) were followed up after coronary catheterization. During a median (inter-quartile range) observation period of 6.13 (3.32-9.21) years, there were 20 (14 %) all-cause deaths, including 11 (8 %) cardiovascular deaths, 17 (12 %) major adverse cardiovascular events, and 17 (12 %) hospital admissions for heart failure. Median NOx level was 34.5 μmol/L (23.9-54.3). NOx was a risk factor for all-cause death [hazard ratio (HR) by unit increase, 1.010, 95 % confidence interval (CI) 1.001-1.018; p = 0.021] and heart failure (HR 1.010, CI 1.001-1.019; p = 0.029). Even after adjustment for age, sex, coronary risk factors, C-reactive protein, log-transformed brain natriuretic peptide, estimated glomerular filtration rate, and nitrate treatment, NOx was a risk factor for all-cause death (HR 1.015, CI 1.004-1.027; p = 0.008) and admission with heart failure (HR 1.018, CI 1.005-1.018, p = 0.007).An increase in serum NOx level does not herald a benign clinical course but is an independent predictor of high risk of any-cause mortality and heart failure.

Recent studies have identified skeletal muscle as a tissue compartment where nitrate and nitrite can be stored and utilized to potentially maintain nitric oxide (NO) homeostasis. Given its capacity to reduce nitrate and nitrite, the molybdopterin-containing enzyme, xanthine oxidoreductase (XOR) has been suggested as a key enzyme within skeletal muscle which catalytically reduces these N-oxides; however, there remains limited insight into the role of XOR in this process as well as how different conditions (e.g. health vs disease and rest vs exercise) may determine when and where, within skeletal muscle, XOR could serve as a significant source of NO. A key factor that determines the extent by which XOR may or may not contribute to NO generation in a biologically relevant manner is the biochemical landscape (e.g. oxygen tension, pH, isoform of XOR (XDH vs. XO) and substrate levels of the microenvironment in normal versus stressed skeletal muscle. As such, a critical focus of this review is the evaluation of the biochemical and physiologic data supporting the role of XOR within skeletal muscle for supplying nitrite and/or NO from endogenous and exogenous sources during pathophysiologic conditions and/or exercise stress.

The aim of this study was to evaluate in vitro the effect of calcium hydroxide [Ca(OH)2], 2% chlorhexidine gel (CHX) on macrophages (RAW 264.7) to produce pro-inflammatory cytokines and nitric oxide after pretreatment with lipoteichoic acid (LTA) of Enterococcus faecalis. Forty-eight human single-rooted teeth were instrumented with R25.08 (RECIPROC) and sterilized by gamma irradiation. LTA was inoculated in the root canal of each specimen for 96 hours. Specimens were instrumented with 40.06 and 50.05 (RECIPROC) and medicated with: I) Pyrogen-free saline solution (SS); II) 2% CHX gel; III) Ca(OH)2 + SS; or IV) Ca(OH)2 + CHX for 14 days. Three samples (S) were performed of the root canal of each specimen at: S1) immediately after instrumentation; S2) after Ethylenediaminetetraacetic acid (EDTA); S3) after intracanal medication removal. Subsequent quantification of cytokines (IL-1β, TNF-α, MIP-1α, IP-10, G-CSF and IL-6) by immunosorbent assay (ELISA) and nitric oxide by the Griess method was carried-out. Data were submitted to a normality test and then analyzed with one-way ANOVA and Tukey test with a significance level of 5% using GraphPad Prism 6. Ca(OH)2 + SS and Ca(OH)2 + CHX presented lower levels of TNF-α, TNF-α, IL-6, G-CSF and nitric oxide. Ca(OH)2 + SS was the most effective in reducing MIP-1α. CHX was effective in reducing IL-6 and G-CSF. Therefore, the combined intracanal medication of calcium hydroxide and chlorhexidine is effective in reducing the cytokines TNF-α, IL-1β, IL-6, G-CSF and nitric oxide. Resumo O objetivo deste estudo foi avaliar in vitro o efeito do hidróxido de cálcio [Ca(OH)2], clorexidina gel a 2% (CHX) em macrófagos (RAW 264.7) na produção de citocinas pró-inflamatórias e óxido nítrico após pré-tratamento com ácido lipoteicóico (LTA) de Enterococcus faecalis. Quarenta e oito dentes humanos uniradiculares foram instrumentados com R25.08 (RECIPROC) e esterilizados por irradiação gama. LTA foi inoculado no canal radicular de cada espécime por 96 horas. Os espécimes foram instrumentados com 40.06 e 50.05 (RECIPROC) e medicados com: I) solução salina apirogênica (SS); II) CHX 2%; III) Ca(OH)2 + SS; ou IV) Ca(OH)2 + CHX durante 14 dias. Três amostras (S) foram realizadas do canal radicular de cada espécime em: S1) imediatamente após a instrumentação; S2) após ácido etilenodiaminotetracético (EDTA); S3) após a retirada da medicação intracanal. Foi realizada a quantificação subsequente de citocinas (IL-1β, TNF-α, MIP-1α, IP-10, G-CSF e IL-6) por imunoensaio (ELISA) e de óxido nítrico pelo método de Griess. Os dados foram submetidos a um teste de normalidade e então analisados com ANOVA one-way e teste de Tukey com nível de significância de 5% usando GraphPad Prism 6. Ca(OH)2 + SS e Ca(OH)2 + CHX apresentaram níveis mais baixos de TNF -α, TNF-α, IL-6, G-CSF e óxido nítrico. Ca(OH)2 + SS foi o mais eficaz na redução de MIP-1α. CHX foi eficaz na redução de IL-6 e G-CSF. Sendo assim a associação de hidróxido de cálcio e clorexidina é eficaz na redução das citocinas TNF-α, IL-1β, IL-6, G-CSF e óxido nítrico.

Bacteria have the ability to invade and survive in host cells to form intracellular bacteria (ICBs), and challenges remain in the intracellular delivery of sufficient antibiotics to remove ICBs. Herein, antimicrobial peptide of epsilon-poly-l-lysine (ePL) and nitric oxide (NO) donors are integrated into nanoparticles (NPs) for ICB treatment without using any antibiotics. ePL was grafted with dodecyl alcohol through ethyl dichlorophosphate to prepare ePL-C

Checkpoint inhibitor pneumonitis (CIP) is a relatively rare adverse event and a potential cause of death in patients treated with immune checkpoint inhibitors (ICIs). Because the symptoms and signs are nonspecific, the diagnosis of CIP is challenging. Additionally, compared with the biomarkers that can monitor the effect of ICIs, there is less research evaluating markers to monitor CIP. We report a case of CIP induced by camrelizumab in a patient with advanced non-small-cell lung cancer, in which the fractional exhaled nitric oxide levels showed obvious increases. Fractional exhaled nitric oxide may have the potential to monitor the condition of airway inflammation in patients using ICIs.We report a patient with advanced lung cancer who experienced shortness of breath induced by immunotherapy. The levels of nitric oxide from the exhaled breath in this case showed obvious increases. Currently, monitoring systems for treatment-related lung injury remain elusive. This is the first report highlighting the potential value of measuring nitric oxide from the exhaled breath to screen for airway inflammation in patients receiving immunotherapy. The dynamic changes of the levels of nitric oxide from the exhaled breath may be correlated with the development of airway inflammation during immunotherapy.

We report that increasing nitric oxide bioavailability via 8 wk of inorganic nitrate/nitrite supplementation improves maximal aerobic exercise capacity in patients with type 2 diabetes mellitus. Similarly, we observed a rightward shift in the gas exchange threshold. Taken together, these data indicate inorganic nitrate/nitrite may serve as a means to improve fitness in patients with type 2 diabetes mellitus.

Nitric oxide (NO) is an endogenous, multipotent biological signaling molecule that participates in several physiological processes. Recently, exogenous supplementation of tumor tissues with NO has emerged as a potential anticancer therapy. In particular, it induces synergistic effects with other conventional therapies (such as chemo-, radio-, and photodynamic therapies) by regulating the activity of P-glycoprotein, acting as a vascular relaxant to relieve tumor hypoxia, and participating in the metabolism of reactive oxygen species. However, NO is highly reactive, and its half-life is relatively short after generation. Meanwhile, NO-induced anticancer activity is dose-dependent. Therefore, the targeted delivery of NO to the tumor is required for better therapeutic effects. In the past decade, NO-generating nanomedicines (NONs), which enable sustained and specific NO release in tumor tissues, have been developed for enhanced cancer therapy. This review describes the recent efforts and preclinical achievements in the development of NON-based cancer therapies. The chemical structures employed in the fabrication of NONs are summarized, and the strategies involved in NON-based cancer therapies are elaborated.

Oroxylin-A (OroA), a flavonoid isolated from Scutellariae baicalensis, alleviates cardiovascular dysfunction. Several procedures for synthesizing OroA have been developed but show low production yield and regioselectivity. We synthesized OroA from baicalin using a one-pot reaction to increase its overall yield. We also determined the chemical properties and mechanism of action of the synthesized OroA and OroA phosphate diethyl ester (OroA-OET) in vascular function. The induction of vascular reactivity by OroA and OroA-OET was evaluated using blood vessel myography and biochemical analysis to assess nitric oxide synthase-mediated nitric oxide production in mouse aortic arteries. OroA and OroA-OET (0.1-30 μM) induced sustained vasorelaxation, which was partly mediated by the endothelium in isolated normal arteries pre-contracted with phenylephrine. OroA and OroA-OET significantly attenuated vasoconstrictors-induced contractile responses. Dilation effects were blocked by the non-selective nitric oxide synthase inhibitor N (omega)-nitro-l-arginine methyl ester but not by tetraethylammonium or 1H-(1,2,4)oxadiazolo [4,3-a]quinoxalin-1-one. Notably, preincubation with OroA and OroA-OET potentiated acetylcholine-induced relaxation and endothelial nitric oxide production in the arteries with the endothelium. OroA and OroA-OET protected against cardiovascular dysfunction. The synthesis and lead compounds used not only improved the yield of OroA from natural sources but also potentially regulated vascular tone.

Low concentrations of nitric oxide (NO) produced by constitutive NO synthase (cNOS) has been shown to suppress apoptosis in pancreatic β-cells. In the present study, the influence of asymmetric dimethylarginine (ADMA), the major endogenous inhibitor of NOS, on the apoptosis-suppressive effect of NO was investigated. The expression of dimethylarginine dimethylaminohydrolase 2 (DDAH2), an ADMA-metabolizing enzyme, in INS-1 β-cells and in mouse pancreatic islets was drastically reduced by in vitro exposure to high-concentration glucose (20 mM) and by in vivo treatment of mice with the insulin receptor blocker S661, which resulted in hyperglycemia, respectively. In line with this, a higher ADMA level was observed in INS-1 cells exposed to 20 mM glucose. The treatment of INS-1 cells with ADMA, similarly to with the NOS inhibitor N

Extrahepatic arginases are postulated to be involved in cardiovascular-related pathologies by competing with nitric oxide synthase (NOS) for the common substrate l-arginine, subsequently decreasing nitric oxide production. However, previous models used to study arginase and NOS competition did not account for steady state level of l-arginine pool, which is dependent on conditions of l-arginine supply and utilization pathways. This work aimed at revisiting the concept of NOS and arginase competition while considering different conditions of l-arginine supply and l-arginine utilization pathways.Mouse macrophage-like RAW cells and human vascular endothelial cells co-expressing NOS and arginase were used to reevaluate the concept of substrate competition between arginase and NOS under conditions of l-arginine supply that mimicked either a continuous (similar to in vivo conditions) or a limited supply (similar to previous in vitro models). Enzyme kinetics simulation models were used to gain mechanistic insight and to evaluate the tenability of a substrate competition between the two enzymes. In addition to arginase and NOS, other l-arginine pathways such as transporters and utilization towards protein synthesis were considered to understand the intricacies of l-arginine metabolism. Our results indicate that when there is a continuous supply of l-arginine, as is the case for most cells in vivo, arginase does not affect NOS activity by a substrate competition. Furthermore, we demonstrate that l-arginine pathways such as transporters and protein synthesis are more likely to affect NOS activity than arginase.Arginase does not outcompete NOS for the common substrate l-arginine. Findings from this study should be considered to better understand the role of arginase in certain pathologies and for the interpretation of in vivo studies with arginase inhibitors.

We hypothesized that differences in nasal nitric oxide (nNO) and fractional exhaled nitric oxide (Feno) relate to prognosis in primary ciliary dyskinesia (PCD).What is the relationship between baseline values and longitudinal evolution of nNO and Feno and ultrastructure, genotype, and respiratory infections in PCD?Prospective, longitudinal, single-center study in adults and children evaluated biannually for up to 10 years. We compared cross-sectional and longitudinal values of nNO and Feno in ultrastructural (inner dynein arm [IDA] and microtubular disorganization [MTD]) and genetic (CCDC39 and CCDC40) groups known to have worse pulmonary function with patients within the ultrastructural and genetic groups with a better prognosis. Linear mixed-effects models were used to evaluate longitudinal associations.One hundred forty-one patients with PCD underwent 1,014 visits. At enrollment, no differences were found in children in nNO or Feno between the IDA and MTD group and the other ultrastructural groups. In adults, nNO (P = .038) and Feno (P = .032) were significantly lower in the IDA and MTD group than in all other combined ultrastructural groups. Feno values were significantly lower in the CCDC39 and CCDC40 group than in the DNAH5 and DNAH11 combined genotype group (P = .033) and in all other genotypes (P = .032). The IDA and MTD group showed a significant decline in nNO with age (P .01) compared with other ultrastructural groups who showed stable levels. The CCDC39 and CCDC40 group showed the steepest decline in nNO over time (P .01) compared with all other genotypes. A higher nNO was associated with lower likelihood of any positive bacterial isolate from the lower respiratory tract (P = .008). Changes in Feno over time did not differ between structural groups or genotypes.Lower nNO in patients with PCD with genetic and ultrastructural changes associated with greater lung function decline may be related to worse prognosis, but whether a low nNO is causal needs further study. If lower nNO directly results in a poorer prognosis, strategies augmenting upper airway nitric oxide production may be worth evaluating.

Fucoidans possess potent anti-inflammatory effects. In the present study, the anti-inflammatory effect of the fucoidan (SFF-PS-F5) isolated from fermented Sargassum fusiforme was evaluated in vitro in RAW 264.7 macrophages and in vivo in zebrafish. The in vitro test results demonstrate that SFF-PS-F5 effectively inhibited nitric oxide (NO) production induced by lipopolysaccharides (LPS) in RAW 264.7 cells. SFF-PS-F5 effectively and concentration-dependently improved the viability of LPS-stimulated RAW 264.7 cells, and reduced the level of prostaglandin E

Manganese-based catalysts attract extensive attentions in low-temperature selective catalytic reduction (SCR) of nitrogen oxide (NOIn this work, electron paramagnetic resonance spectrometer and density functional theory are combined to reveal surface characterizations of manganese oxide and Ce/La-doped manganese oxides.As a result, superoxide radical (O

Hypertension is associated with endothelial dysfunction and decreased nitric oxide (NO). It has been proposed that decreasing oxidative stress may help regulate blood pressure by increasing NO concentration. Therefore, the purpose of this systematic review was to determine whether the antioxidant resveratrol effects NO-mediated vascular outcomes in hypertension. A comprehensive literature search of PubMed and EBSCOhost databases was conducted using the terms: "resveratrol" and "nitric oxide or NO" and "hypertension or high blood pressure." Searches were not restricted for year of publication or study design but limited to full-text studies from scholarly, peer-reviewed journals. Ten animal studies published between 2005 and 2017 were identified. Human studies did not meet criteria and were not included. Articles were critically assessed using the Academy of Nutrition and Dietetics' Evidence Analysis Library Quality Criteria Worksheet. All studies evaluated resveratrol supplementation and at least one NO outcome measure including: circulating NO metabolites, endothelial nitric oxide synthase (eNOS) expression, eNOS phosphorylation, and eNOS uncoupling. All but one study assessed blood pressure. Nine of ten studies reported positive significant results of resveratrol supplementation on NO outcomes, and in all but one study, this was seen concomitantly with decreases in blood pressure. Resveratrol supplementation shows promise for improving NO-mediated vascular outcomes and improving blood pressure. Translation to human studies is warranted, with dose of resveratrol considered, as the human equivalency doses are not consistent amongst animal studies. Additionally, a standard battery of tests examining NO-mediated vascular outcomes is needed to ensure generalizability among studies to determine dose-duration effects.

While immunotherapy has emerged as a promising strategy to treat glioblastoma multiforme (GBM), the limited availability of immunotherapeutic agents in tumors due to the presence of the blood-brain barrier (BBB) and immunosuppressive tumor microenvironment dampens efficacy. Nitric oxide (NO) plays a role in modulating both the BBB and tumor vessels and could thus be delivered to disrupt the BBB and improve the delivery of immunotherapeutics into GBM tumors. Herein, we report an immunotherapeutic approach that utilizes CXCR4-targeted lipid‑calcium-phosphate nanoparticles with NO donors (LCP-NO NPs). The delivery of NO resulted in enhanced BBB permeability and thus improved gene delivery across the BBB. CXCR4-targeted LCP-NO NPs delivered siRNA against the immune checkpoint ligand PD-L1 to GBM tumors, silenced PD-L1 expression, increased cytotoxic T cell infiltration and activation in GBM tumors, and suppressed GBM progression. Thus, the codelivery of NO and PD-L1 siRNA by these CXCR4-targeted NPs may serve as a potential immunotherapy for GBM.

Several lines of evidence suggest that the intra- and inter-cellular messenger nitric oxide (NO) is critically involved in anxiety. Contrasting findings are reported, however, regarding the effects of NO donors in preclinical models of anxiety. Previous research has shown that challenge with a low dose range of the NO donors sodium nitroprusside (SNP) and molsidomine induce anti-anxiety-like effects in rodents. There is poor information concerning the effects of these NO donors on preclinical models mimicking the obsessive-compulsive disorder (OCD) and the post-traumatic stress disorder (PTSD). The present research was designed to investigate this issue in the rat. To this end, the mCPP-induced excessive self-grooming and the contextual fear conditioning (CFC) test which are behavioural paradigms resembling OCD and PTSD respectively in rodents were used. Acute administration of SNP (1 mg/kg) and molsidomine (4 mg/kg) attenuated excessive self-grooming induced by the 5-HTsub2C/subreceptor agonist mCPP (0.6 mg/kg). Further, at the same dosage, both these NO donors reduced freezing behaviour evidenced in the CFC test. The present results suggest that NO donors are efficacious in attenuating abnormal behaviours revealed in animal models of OCD and PTSD which are among the most severe pathologies of anxiety.

Elemene is a second-line broad-spectrum anti-tumour drug that has been used in China for more than two decades. However, its main anti-tumour ingredient, β-elemene, has disadvantages, including excessive lipophilicity and relatively weak anti-tumour efficacy. To improve the anti-tumour activity of β-elemene, based on its minor molecular weight character, we introduced furoxan nitric oxide (NO) donors into the β-elemene structure and designed six series of new generation β-elemene NO donor hybrids. The synthesised compounds could effectively release NO in vitro, displayed significant anti-proliferative effects on U87MG, NCI-H520, and SW620 cell lines. In the orthotopic glioma model, compound Id significantly and continuously suppressed the growth of gliomas in nude mice, and the brain glioma of the treatment group was markedly inhibited (>90%). In short, the structural fusion design of NO donor and β-elemene is a feasible strategy to improve the in vivo anti-tumour activity of β-elemene.

The dorsomedial periaqueductal gray (dmPAG) is a mesencephalic area and has numerous functions including cardiovascular regulation. Because nitric oxide (NO) is present in the dmPAG, here we investigate, the probable cardiovascular effect of NO in the dmPAG.Five groups (n = 6 for each group) were used as follows: (1) control; (2) L-NAME (NMicroinjection of L-NAME significantly increased ∆SBP, ∆MAP, and ∆HR more than saline (from p 0.05 to p 0.001). L-Arg only significantly increased ∆HR (p 0.05). In the L-Arg + L-NAME group, the above parameters also significantly increased (from p 0.01 to p 0.05) but not as significantly as with L-NAME alone. Microinjection of SNP significantly decreased ∆SBP and ∆MAP more than in the control and L-NAME groups (from p 0.01 to p 0.001), but ∆HR did not change significantly.The results indicated that NO in dmPAG has an inhibitory effect on cardiovascular responses in anesthetized rats.

Siderophores are synthesized by microbes to facilitate iron acquisition required for growth. Catecholate, hydroxamate, and α-hydroxycarboxylate groups comprise well-established ligands coordinating Fe(III) in siderophores. Recently, a C-type diazeniumdiolate ligand in the newly identified amino acid graminine (Gra) was found in the siderophore gramibactin (Gbt) produced by Paraburkholderia graminis DSM 17151. The N-N bond in the diazeniumdiolate is a distinguishing feature of Gra, yet the origin and reactivity of this C-type diazeniumdiolate group has remained elusive until now. Here, we identify l-arginine as the direct precursor to l-Gra through the isotopic labeling of l-Arg, l-ornithine, and l-citrulline. Furthermore, these isotopic labeling studies establish that the N-N bond in Gra must be formed between the Nδ and Nω of the guanidinium group in l-Arg. We also show the diazeniumdiolate groups in apo-Gbt are photoreactive, with loss of nitric oxide (NO) and H+ from each d-Gra yielding E/Z oxime isomers in the photoproduct. With the loss of Gbt's ability to chelate Fe(III) upon exposure to UV light, our results hint at this siderophore playing a larger ecological role. Not only are NO and oximes important in plant biology for communication and defense, but so too are NO-releasing compounds and oximes attractive in medicinal applications.

This study was performed to investigate serum homocysteine and nitric oxide levels in cats with Feline Infectious Peritonitis and present some biochemical and pathological alterations related to the disease. The animal material of this study consisted of thirty Turkish Van Cats of different ages and genders that were definitely diagnosed with the disease by post-mortem examinations and immunohistochemistry. The control group consisted of 6 healthy Turkish Van Cats of different ages and genders that were brought for routine clinical examination. Cats in the study group had clinical findings such as loss of appetite, weight loss, high fever, fever not reduced despite antibiotics, jaundice, dehydration, vomiting, respiratory system symptoms, anemia, nervous findings, uveitis, and ascites. These cats were monitored and following the death, post-mortem examinations were performed and cases with a definitive diagnosis were included in the study. Among the cats consisting study group, while 25 had the dry form of the disease, 5 had wet form. According to the hematological results, there was a statistically significant reduction in platelet counts. The biochemical results showed statistically significant alterations that creatinine, aspartate aminotransferase, alkaline phosphatase, creatine kinase myocardial band, homocysteine, and nitric oxide concentrations were higher than the control group. Besides albumin concentrations were lower and the albumin/globulin ratio was 0.53. As a result; this is the first detailed study in Turkish Van Cats with Feline Infectious Peritonitis that evaluated clinical, hematological, biochemical, and pathological findings. Furthermore, serum homocysteine and nitric oxide levels were evaluated for the first time in cats with vasculitis which is the most important complication of the disease. It is concluded that the evaluation of serum homocysteine and nitric oxide concentrations in Feline Infectious Peritonitis may assist the antemortem diagnosis of the disease.

Agriculture and ecosystem are negatively influenced by the abiotic stresses which create solemn pressures on plants as they are sessile in nature leading to excessive losses in economy. For maintenance of sustainable agriculture and to fulfil the cumulative call of food for rapidly growing population worldwide, it becomes crucial to protects the crop plants from climate fluctuations. Plants fight back against these challenges by generation of redox molecules comprising reactive oxygen species (ROS) and reactive nitrogen species (RNS) and cause modulation at cellular, physiological and molecular levels. Nitric oxide (NO) deliver tolerance to several biotic and abiotic stresses in plants by acting as signalling molecule or free radicals. It is also intricated in several developmental processes in plants using different mechanisms. Supplementation of exogenous NO reduce toxicity of abiotic stresses and provide resistance. In this review article, we summarize the recent research studies (five years) depicting the functional role of NO in alleviation of abiotic stresses such as drought, cold, heat, heavy metals and flooding. Moreover, by investigating studies found that among heavy metals works associated with Hg, Pb, and Cr is limited comparatively. Additionally, role of NO in abiotic stress resistance such as cold, freezing and heat stress less/poorly investigated. Consequently, further emphasis should be diverted towards how NO can facilitate protection against these stresses. In recent studies mostly beneficial role of NO against abiotic challenges have been elucidated by observing physiological/biochemical parameters but relatively inadequate research done at the transcripts level or gene regulation subsequently researchers should include it in future. Lastly, brief outline and an evaluative discussion on the present information and future prospective provided. Altogether, these inclusive experimental agendas could facilitate in future to produce climate tolerant plants. This will help to confront the constant fluctuations in the environment and to reduce the challenges in way of agriculture productivity and global food demands.

Circulating tumor cells (CTCs) acquire enhanced anti-anoikis abilities after experiencing flow shear stress in the circulatory system. Our previous study demonstrated that low shear stress (LSS) promotes anoikis resistance of human breast carcinoma cells via caveolin-1 (Cav-1)-dependent extrinsic and intrinsic apoptotic pathways. However, the underlying mechanism how LSS enhanced Cav-1 expression in suspended cancer cells remains unclear. Herein, we found that LSS induced redox signaling was involved in the regulation of Cav-1 level and anoikis resistance in suspension cultured cancer cells. Exposure of human breast carcinoma MDA-MB-231 cells to LSS (2 dyn/cm

Persistent pulmonary hypertension of the newborn (PPHN) is a condition caused by failure of pulmonary vascular adaptation at birth, resulting in severe hypoxia. Several therapeutic modalities are being tried in developing countries where established therapies (inhaled nitric oxide and extracorporeal membrane oxygenation) are widely unavailable. This study aimed to assess the efficacy of milrinone versus sildenafil as available alternative therapeutics in treating PPHN. Forty neonates (gt;34 weeks) admitted to neonatal intensive care units with evidence of PPHN were randomly allocated to receive either oral sildenafil (0.5-2 mg/kg/6 hours) or intravenous milrinone (0.25-0.75 mic/kg/min). Primary outcomes included improvements in systolic pulmonary artery pressure and oxygen saturation index (OSI) at 24 and 48 hours after treatment. Secondary outcomes included the duration of hospitalization and mechanical ventilation. The ClinicalTrials identifier is NCT04391478. Both groups showed significant improvement in the post-treatment hemodynamic variables compared with pretreatment levels ( Plt; 0.05 for all parameters). Systolic pulmonary artery pressure and OSI values significantly improved in both study groups compared with baseline ( Plt; 0.001). The 24-hour and 48-hour post-treatment OSI values were much lower in the milrinone group than those in the sildenafil group ( Plt; 0.05). The length of hospital stay was significantly shorter in the milrinone group than that in the sildenafil group ( Plt; 0.05). There were no significant differences in the duration of mechanical ventilation, incidence of intracranial hemorrhage and pulmonary hemorrhage, or mortality between the 2 groups ( Pgt; 0.05). In conclusion, milrinone and sildenafil are effective and well-tolerated in neonates with PPHN, particularly when inhaled nitric oxide and extracorporeal membrane oxygenation are not available. Milrinone is superior to sildenafil in improving oxygenation without lowering blood pressure parameters.

Myogenic and flow-induced reactivity contribute to cerebral autoregulation, with potentially divergent roles for smaller versus larger arteries. The present study tested the hypotheses that compared with first-order (1A) branches of the middle cerebral artery, second- and third-order branches (2A and 3A, respectively) exhibit greater myogenic reactivity but reduced flow-induced constriction. Furthermore, nitric oxide synthase (NOS) inhibition may amplify myogenic reactivity and abolish instances of flow-induced dilation. Isolated porcine cerebral arteries mounted in a pressure myograph were exposed to incremental increases in intraluminal pressure (40-120 mmHg

Gastrointestinal motility is crucial to gut health and has been associated with different disorders such as inflammatory bowel diseases and postoperative ileus. Despite rat and mouse being the two animal models most widely used in gastrointestinal research, minimal studies in rats have investigated gastrointestinal motility. Therefore, our study provides a comparison of colonic motility in the mouse and rat to clarify species differences and assess the relative effectiveness of each animal model for colonic motility research. We describe the protocol modifications and optimization undertaken to enable video imaging of colonic motility in the rat. Apart from the broad difference in terms of gastrointestinal diameter and length, we identified differences in the fundamental histology of the proximal colon such that the rat had larger villus height-to-width and villus height-to-crypt depth ratios compared with mouse. Since gut motility is tightly regulated by the enteric nervous system (ENS), we investigated how colonic contractile activity within each rodent species responds to modulation of the ENS inhibitory neuronal network. Here we used

In diabetic nephropathy, hyperglycemia elevates albumin glycation and also results in increased plasma aldosterone. Both glycation and aldosterone are reported to cause oxidative stress by downregulating the NRF-2 pathway and thereby resulting in reduced levels of antioxidants and glycation detoxifying enzymes. We hypothesize that an interaction between aldosterone and glycated albumin may be responsible for amplified oxidative stress and concomitant renal cell damage. Hence, human serum albumin was glycated by methylglyoxal (MGO) in presence of aldosterone. Different structural modifications of albumin, functional modifications and aldosterone binding were analyzed. HEK-293 T cells were treated with aldosterone+glycated albumin along with inhibitors of receptors for mineralocorticoid (MR) and advanced glycation endproducts (RAGE). Cellular MGO content, antioxidant markers (nitric oxide, glutathione, catalase, superoxide dismutase, glutathione peroxidase), detoxification enzymes (aldose reductase, Glyoxalase I, II), their expression along with NRF-2 and Keap-1 were measured. Aldosterone binds to albumin with high affinity which is static and spontaneous. Cell treatment by aldosterone+glycated albumin increased intracellular MGO, MR and RAGE expression; hampered antioxidant, detoxification enzyme activities and reduced NRF-2, Keap-1 expression. Thus, the glycated albumin-aldosterone interaction and its adverse effect on renal cells were confirmed. The results will help in developing better pharmacotherapeutic strategies for diabetic nephropathy.

Adropin is a peptide largely secreted by the liver and known to regulate energy homeostasis; however, it also exerts cardiovascular effects. Herein, we tested the hypothesis that low circulating levels of adropin in obesity and type 2 diabetes (T2D) contribute to arterial stiffening. In support of this hypothesis, we report that obesity and T2D are associated with reduced levels of adropin (in liver and plasma) and increased arterial stiffness in mice and humans. Establishing causation, we show that mesenteric arteries from adropin knockout mice are also stiffer, relative to arteries from wild-type counterparts, thus recapitulating the stiffening phenotype observed in T2D

Cerebral parenchymal arterioles from menopause mice showed increased myogenic tone. We identified an impairment in smooth muscle cell BKCa channel activity, without a reduction in endothelium-dependent dilation or nitric oxide production. Microvascular dysfunction was associated with a reduction in neurovascular responses after somatosensory stimulation. Despite the neurovascular impairment, cognitive abilities were maintained in menopausal mice.

Platelets are the "guardians" of the blood circulatory system. At sites of vessel injury, they ensure hemostasis and promote immunity and vessel repair. However, their uncontrolled activation is one of the main drivers of thrombosis. To keep circulating platelets in a quiescent state, the endothelium releases platelet antagonists including nitric oxide (NO) that acts by stimulating the intracellular receptor guanylyl cyclase (GC). The latter produces the second messenger cyclic guanosine-3',5'-monophosphate (cGMP) that inhibits platelet activation by stimulating protein kinase G, which phosphorylates hundreds of intracellular targets. Intracellular cGMP pools are tightly regulated by a fine balance between GC and phosphodiesterases (PDEs) that are responsible for the hydrolysis of cyclic nucleotides. Phosphodiesterase type 5 (PDE5) is a cGMP-specific PDE, broadly expressed in most tissues in humans and rodents. In clinical practice, PDE5 inhibitors (PDE5i) are used as first-line therapy for erectile dysfunction, pulmonary artery hypertension, and lower urinary tract symptoms. However, several studies have shown that PDE5i may ameliorate the outcome of various other conditions, like heart failure and stroke. Interestingly, NO donors and cGMP analogs increase the capacity of anti-platelet drugs targeting the purinergic receptor type Y, subtype 12 (P2Y12) receptor to block platelet aggregation, and preclinical studies have shown that PDE5i inhibits platelet functions. This review summarizes the molecular mechanisms underlying the effect of PDE5i on platelet activation and aggregation focusing on the therapeutic potential of PDE5i in platelet disorders, and the outcomes of a combined therapy with PDE5i and NO donors to inhibit platelet activation.

The nitric oxide (NO)/cGMP pathway has been extensively studied for its pivotal role in synaptic plasticity and memory processes, resulting in an increase of cAMP response element-binding (CREB) phosphorylation, and consequent synthesis of plasticity-related proteins. The NO/cGMP/CREB signaling is downregulated during aging and neurodegenerative disorders and is affected by Amyloid-β peptide (Aβ) and tau protein, whose increase and deposition is considered the key pathogenic event of Alzheimer's disease (AD). On the other hand, in physiological conditions, the crosstalk between the NO/cGMP/PKG/CREB pathway and Aβ ensures long-term potentiation and memory formation. This review summarizes the current knowledge on the interaction between the NO/cGMP/PKG/CREB pathway and Aβ in the healthy and diseased brain, offering a new perspective to shed light on AD pathophysiology. We will focus on the synaptic mechanisms underlying Aβ physiological interplay with cGMP pathway and how this balance is corrupted in AD, as high levels of Aβ interfere with NO production and cGMP molecular signaling leading to cognitive impairment. Finally, we will discuss results from preclinical and clinical studies proposing the increase of cGMP signaling as a therapeutic strategy in the treatment of AD.

Mechanical forces are translated into biochemical stimuli by mechanotransduction channels, such as the mechanically activated cation channel Piezo2. Lung Piezo2 expression has recently been shown to be restricted to endothelial cells. Hence, we aimed to investigate the role of Piezo2 in regulation of pulmonary vascular function and structure, as well as its contribution to development of pulmonary arterial hypertension (PAH). The expression of Piezo2 was significantly reduced in pulmonary microvascular endothelial cells (MVECs) from patients with PAH, in lung tissue from mice with a Bmpr2+/R899X knock-in mutation commonly found in patients with pulmonary hypertension, and in lung tissue of monocrotaline (MCT) and sugen-hypoxia-induced PH (SuHx) PAH rat models, as well as from a swine model with pulmonary vein banding. In MVECs, Piezo2 expression was reduced in response to abnormal shear stress, hypoxia, and TGFβ stimulation. Functional studies in MVECs exposed to shear stress illustrated that siRNA-mediated Piezo2 knockdown impaired endothelial alignment, calcium influx, phosphorylation of AKT, and nitric oxide production. In addition, siPiezo2 reduced the expression of the endothelial marker PECAM-1 and increased the expression of vascular smooth muscle markers ACTA2, SM22a, and calponin. Thus, Piezo2 acts as a mechanotransduction channel in pulmonary MVECs, stimulating shear-induced production of nitric oxide and is essentially involved in preventing endothelial to mesenchymal transition. Its blunted expression in pulmonary hypertension could impair the vasodilator capacity and stimulate vascular remodeling, indicating that Piezo2 might be an interesting therapeutic target to attenuate progression of the disease.NEW & NOTEWORTHY The mechanosensory ion channel Piezo2 is exclusively expressed in lung microvascular endothelial cells (MVECs). Patient MVECs as well as animal models of pulmonary (arterial) hypertension showed lower expression of Piezo2 in the lung. Mechanistically, Piezo2 is required for calcium influx and NO production in response to shear stress, whereas stimuli known to induce endothelial to mesenchymal transition (EndMT) reduce Piezo2 expression in MVECs, and Piezo2 knockdown induces a gene and protein expression pattern consistent with EndMT.

Arginase is a ubiquitous enzyme in the urea cycle (UC) that hydrolyzes L-arginine to urea and L-ornithine. Two mammalian arginase isoforms, arginase1 (ARG1) and arginase2 (ARG2), play a vital role in the regulation of β-cell functions, insulin resistance (IR), and vascular complications via modulating L-arginine metabolism, nitric oxide (NO) production, and inflammatory responses as well as oxidative stress. Basic and clinical studies reveal that abnormal alterations of arginase expression and activity are strongly associated with the onset and development of diabetes mellitus (DM) and its complications. As a result, targeting arginase may be a novel and promising approach for DM treatment. An increasing number of arginase inhibitors, including chemical and natural inhibitors, have been developed and shown to protect against the development of DM and its complications. In this review, we discuss the fundamental features of arginase. Next, the regulatory roles and underlying mechanisms of arginase in the pathogenesis and progression of DM and its complications are explored. Furthermore, we review the development and discuss the challenges of arginase inhibitors in treating DM and its related pathologies.