Nitric Oxide Synthase Activity Research Articles

유용미생물에 의한 저이용 산채류의 복합발효 중 생리활성 성분 및 항염증 변화

It was confirmed that complex fermentation (CF) was more efficient than single-strain fermentations in inducing changes in the contents of phenolic compounds of Maclura tricuspidate and Pyrus Montana Nakai. A mixture of Maclura tricuspidata, Pyrus montana Nakai, Platycodon grandiflorum and Codonopsis lanceolata were fermented in CF using Aspergillus shirousamii (koji), yeast, and lactic acid bacteria (LAB) for 24 days, and the pH, °Brix, total acidity, anti-oxidant activity, polyphenol content, nitric oxide (NO), and Western blotting of inducible nitric oxide synthase (iNOS), cyclo-oxygenase-2 (COX-2), and tumor necrosis factor-α (TNF-α) of the sample were determined. There was no significant change in pH and total acidity. °Brix significantly decreased from day 6 onwards. HPLC confirmed that the concentrations of chlorogenic acid, 4-hydrobenzoic acid, vanillic acid, and caffeic acid significantly increased from day 18 during the fermentation. Additionally, DPPH, ABTS radical scavenging activity, total phenol, and total flavonoid were confirmed to be increased until 18 days. NO was significantly inhibited from day 6, along with significant inhibition of iNOS, COX-2, and TNF-a. In conclusion, this study confirmed that CF of low-use (or underutilized) wild vegetables enhances phenolic compounds. It effectively suppresses NO, iNOS, COX-2, and TNF-α, markers of inflammation-related pathogenesis. Altogether, our results suggest that CF of the above plants has a potential anti-inflammatory effect.

Endoplasmic Reticulum Stress Induces Vasodilation in Liver Vessels That Is Not Mediated by Unfolded Protein Response.

There is a growing body of evidence that ER stress and the unfolded protein response (UPR) play a key role in numerous diseases. Impaired liver perfusion and ER stress often accompany each other in liver diseases. However, the exact impact of ER stress and UPR on the hepatic perfusion is not fully understood. The aim of this study was to disclose the effect of ER stress and UPR on the size of liver vessels and on the levels of Ca2+ and nitric oxide (NO), critical regulators of vascular tonus. This study was carried out in precisely cut liver tissue slices. Confocal microscopy was used to create 3D images of vessels. NO levels were determined either using either laser scan microscopy (LSM) in cells or by NO-analyser in medium. Ca2+ levels were analysed by LSM. We show that tunicamycin, an inducer of ER stress, acts similarly with vasodilator acetylcholine. Both exert a similar effect on the NO and Ca2+ levels; both induce significant vasodilation. Notably, this vasodilative effect persisted despite individual inhibition of UPR pathways-ATF-6, PERK, and IRE1-despite confirming the activation of UPR. Experiments with HUVEC cells showed that elevated NO levels did not result from endothelial NO synthase (eNOS) activation. Our study suggests that tunicamycin-mediated ER stress induces liver vessel vasodilation in an NO-dependent manner, which is mediated by intracellular nitrodilator-activatable NO store (NANOS) in smooth muscle cells rather than by eNOS.

The Potential of Bioactive Fish Collagen Oligopeptides against Hydrogen Peroxide-Induced NIH/3T3 and HUVEC Damage: The Involvement of the Mitochondria.

Extensive in vivo investigations have demonstrated the antioxidant properties of fish collagen oligopeptides (FCOPs). One of the main causes of aging and chronic non-communicable diseases is oxidative stress. Therefore, FCOPs have a broad range of applications in illness prevention and delaying aging from the standpoint of the "food is medicine" theory. However, the mechanisms that underpin the antioxidant activity of FCOPs are not completely understood. The specific objective of this essay was to investigate the antioxidant effect of FCOPs and its possible mechanism at the cellular level. Mouse embryonic fibroblasts NIH/3T3 and human vein endothelial cells (HUVECs) were exposed to 200 µM hydrogen peroxide containing different concentrations of FCOPs for 4 h and were supplemented with different concentrations of FCOPs for 24 h. Normal growth medium without FCOPs was applied for control cells. An array of assays was used to evaluate the implications of FCOPs on cellular oxidative stress status, cellular homeostasis, inflammatory levels, and mitochondrial function. We found that FCOPs exerted a protective effect by inhibiting reactive oxygen species (ROS) production, enhancing superoxide dismutase (SOD) and endothelial nitric oxide synthase (eNOS) activities and cell viability, inhibiting cell cycle arrest in the G1 phase, suppressing interleukin-1β (IL-1β), IL-6, matrix metalloproteinase-3 (MMP-3) and intercellular adhesion molecule-1(ICAM-1) secretion, downregulating nuclear factor-kappa B (NF-κB) activity, protecting mitochondrial membrane potential, and increasing ATP synthesis and NAD+ activities in both cells. FCOPs had a stronger antioxidant impact on NIH/3T3 than on HUVECs, simultaneously increasing glutathione peroxidase (GSH-Px) activity and decreasing malondialdehyde (MDA) content in NIH/3T3. These findings indicate that FCOPs have antioxidant effects on different tissue cells damaged by oxidative stress. FCOPs were therefore found to promote cellular homeostasis, inhibit inflammation, and protect mitochondria. Meanwhile, better health outcomes will be achieved by thoroughly investigating the effective dose and intervention time of FCOPs, as the absorption efficiency of FCOPs varies in different tissue cells.

Effect of leptin on nitrergic neurons in the lateral hypothalamic area and the supraoptic nucleus of rats

ABSTRACT The adipocyte-derived hormone, leptin, plays a key role in the maintenance of energy homeostasis. Leptin binds to the long form of its receptor, which is predominantly expressed in various hypothalamic regions, including the lateral hypothalamic area (LH) and supraoptic nucleus (SO). Several studies have suggested that leptin directly activates neuronal nitric oxide synthase, leading to increased nitric oxide production. We used histochemistry for nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) as a marker for nitric oxide synthase activity and assessed the effect of leptin on nitrergic neurons in the LH and SO of rats. We found that intraperitoneal administration of leptin led to a significant increase in the number of NADPH-d-positive neurons in the LH and SO. In addition, the intensity (optical density) of NADPH-d staining in LH and SO neurons was significantly elevated in rats that received leptin compared with saline-treated rats. These findings suggest that nitrergic neurons in the LH and SO may be implicated in mediating the central effects of leptin.

ROCK1 inhibition improves wound healing in diabetes via RIPK4/AMPK pathway.

Refractory wounds are a severe complication of diabetes mellitus that often leads to amputation because of the lack of effective treatments and therapeutic targets. The pathogenesis of refractory wounds is complex, involving many types of cells. Rho-associated protein kinase-1 (ROCK1) phosphorylates a series of substrates that trigger downstream signaling pathways, affecting multiple cellular processes, including cell migration, communication, and proliferation. The present study investigated the role of ROCK1 in diabetic wound healing and molecular mechanisms. Our results showed that ROCK1 expression significantly increased in wound granulation tissues in diabetic patients, streptozotocin(STZ)-induced diabetic mice, and db/db diabetic mice. Wound healing and blood perfusion were dose-dependently improved by the ROCK1 inhibitor fasudil in diabetic mice. In endothelial cells, fasudil and ROCK1 siRNA significantly elevated the phosphorylation of adenosine monophosphate-activated protein kinase at Thr172 (pThr172-AMPKα), the activity of endothelial nitric oxide synthase (eNOS), and suppressed the levels of mitochondrial reactive oxygen species(mtROS) and nitrotyrosine formation. Experiments using integrated bioinformatics analysis and coimmunoprecipitation established that ROCK1 inhibited pThr172-AMPKα by binding to receptor-interacting serine/threonine kinase 4 (RIPK4). These results suggest that fasudil accelerated wound repair and improved angiogenesis at least partially through the ROCK1/RIPK4/AMPK pathway. Fasudil may be a potential treatment for refractory wounds in diabetic patients.

Effects of dietary D-mannose supplementation on growth performance, intestinal digestive capacity, gut microbiota, and ammonia tolerance of largemouth bass Micropterus salmoides

To investigate the effects of D-mannose on the growth performance, intestinal digestion capacity, intestinal microbiota composition, and ammonia tolerance of largemouth bass, experiments were conducted using largemouth bass fry with an average body weight of 7.41±0.05 g. Three experimental groups were designed, with 3 replicates per group and 30 fish per replicate. The fish were fed with feed containing different concentrations of D-mannose (0.00%, 1.00%, and 2.00% - Control, 1% mannose, 2% mannose) and were given full satiation twice a day for 56 days. The results indicated that the addition of 2% D-mannose in the feed enhanced the growth performance of the largemouth bass while reducing the feed conversion ratio. The addition of D-mannose in the feed increased the activity of digestive enzymes in the intestines (lipase, α-amylase, pepsin, alkaline phosphatase, Na+/K+ATPase, gamma-glutamyl transpeptidase, and creatine kinase). It also led to an increase in intestinal villi height and intestinal wall thickness; Adding D-mannose reduced the abundance of Staphylococcus and Achromobacter in the gut microbiota, while increasing the abundance of Aurantimicrobium. After being subjected to ammonia stress for 96 hours, the addition of D-mannose in the feed resulted in a decrease in mortality rate and neuronal nitric oxide synthase activity, while simultaneously enhancing the activity of liver argininosuccinate synthetase, argininosuccinate lyase, arginase, ornithine transcarboxylase, and inducible nitric oxide synthase. Adding D-mannose to the feed promotes the growth of largemouth bass, enhances their digestive capacity, and has a positive impact on their intestinal microbiota composition. Furthermore, it has been demonstrated that it can enhance the tolerance of largemouth bass to ammonia.

NITRIC OXIDE METABOLISM IN RAT SMALL INTESTINE TISSUES FOLLOWING SURGICAL TRAUMA REPRODUCED IN EXPERIMENTAL MODEL OF POSTTRAUMATIC STRESS DISORDER

The article investigates the parameters of the nitric oxide (NO) system in the small intestine tissues of rats subjected to surgical trauma within an experimental model of post-traumatic stress disorder (PTSD). The study involved 42 white Wistar rats weighing 210-230 g, divided into 6 groups: Group 1 comprised intact animals, Group 2 included animals with the PTSD induced through single-prolonged stress (SPS), Group 3 consisted of rats subjected to a sham surgical operation, Group 4 comprised animals undergoing laparotomy, Group 5 involved rats undergoing a sham surgical operation following SPS, and Group 6 included animals undergoing laparotomy under modeled SPS. Nitric oxide synthase (NOS) activity in small intestine homogenates was assessed using spectrophotometric methods; peroxynitrite formation was determined by analyzing the content of peroxynitrite of alkali and alkaline earth metals. The study has demonstrated the SPS results in evident signs of nitrosative stress in the small intestine tissues of rats: it enhances NOS activity by activating the inducible isoform, reduces the constitutive NOS activity and coupling, and elevates the concentration of peroxynitrites of alkali and alkaline-earth metals. On the 7th day following laparotomy under PTSD modelling, nitrosative stress indicators in the small intestine tissues such as total and inducible NOS activity, as well as peroxynitrite concentrations of alkaline and alkaline-earth metals, significantly surpassed their levels following a single laparotomy under simulated single prolonged stress.

IMPACT OF NF-κB AND NRF2 TRANSCRIPTION FACTOR MODULATORS ON METABOLIC CHARACTERISTICS IN MANDIBLE BONES OF RATS DURING RECOVERY FROM INCOMPLETE FRACTURE UNDER CHRONIC ALCOHOL INTOXICATION

This study aims at investigating the influence of specific modulators of NF-κB and Nrf2 transcription factors on oxidative-nitrosative stress indicators and bone biopolymer depolymerization in mandibular bone following incomplete fracture under chronic alcohol intoxication (CAI). Twenty-eight white male Wistar rats were divided into five groups: Group 1 comprised "falsely injured" rats, while Group 2 underwent incomplete mandibular fracture (IMF) under CAI exposure. Rats in groups 3 and 4 received intraperitoneal injections of ammonium pyrrolidinium dithiocarbamate, an inhibitor of NF-κB activation, in a dose of 76 mg/kg, and dimethyl fumarate, an Nrf2 inducer, in a dose of 15 mg/kg three times a week for 14 days following the modeling of IMF under CAI exposure. The activity of total NO synthase, including its constitutive and inducible isoforms, along with ornithine decarboxylase, and concentrations of peroxynitrites of alkaline and alkaline-earth metals, free hydroxyproline, N-acetylneuraminic, and hexuronic acids were assessed in the homogenate of the standard mandible area using a spectrophotometric method. The findings have demonstrated that the administration of ammonium pyrrolidine dithiocarbamate and dimethyl fumarate notably decreased the activity of NO synthase (primarily its inducible isoform) and the concentration of peroxynitrite in the mandibular bone homogenate, while increasing the activity of ornithine decarboxylase, a key enzyme in polyamine biosynthesis. Furthermore, under experimental conditions, the use of ammonium pyrrolidine dithiocarbamate and dimethyl fumarate limited the depolymerization of bone biopolymers (collagen, glycoproteins, and proteoglycans), thereby facilitating effective reparative osteogenesis.

THE INFLUENCE OF QUERCETIN ON THE PRODUCTION OF REACTIVE OXYGEN-NITROGEN FORMS IN THE STRUCTURE OF THE INTERSTITIAL SPACE OF RAT TESTICLES WITH LONG-TERM EFFECT OF TRIPTORELIN

Quercetin is a flavonoid commonly found in fruits, vegetables, and seeds. Flavonoids can help prevent cardiovascular diseases, reduce the risk of degenerative brain processes and cancer. Studies have shown that blocking the synthesis of luteinising hormone can lead to oxidative stress in the liver, heart, and salivary glands of rats. The purpose of this study was to assess alterations in the interstitial space of rat testes, identify sources of nitric oxide production, and measure the intensity of oxidative stress in the testes during long-term experimental central blocking of luteinising hormone synthesis by tryptorelin. The study was conducted on 15 sexually mature male white rats. The animals were divided into two groups. The first group (control) received a subcutaneous injection of 0.9% sodium chloride solution. The second group (experimental) received a subcutaneous injection of tryptorelin at a dose of 0.3 mg/kg of active ingredient for 365 days, with simultaneous addition of quercetin to the diet, which was administered orally through a gastric tube three times a day. Total nitric oxide production was assessed by measuring the activity of total NO synthase (gNOS). The activity of gNOS was determined by the increase in nitrite (NO2-) after incubation in Tris-buffered saline. The nitrite concentration was determined using the Gris-Ilosvay reagent at a wavelength of 540 nm. The activity of the inducible (iNOS) and constitutive (cNOS) isoforms was also determined using a selective iNOS inhibitor, aminoguanidine hydrochloride. The production of superoxide anion radical (O2--) was measured by the increase in the formation of diformazan resulting from the reaction of O2-- with nitroblue tetrazolium after incubation in a buffered solution containing sodium hydroxide. The administration of quercetin mitigates the adverse effects of tryptorelin on the structural and functional components of the connective tissue in the rat testes. This effect is observed on day 365 and is characterised by fibrosis and impaired nitric oxide production by constitutive isoforms of NO synthase.

Intrinsic endothelial hyperresponsiveness to inflammatory mediators drives acute episodes in models of Clarkson disease.

Clarkson disease, or monoclonal gammopathy-associated idiopathic systemic capillary leak syndrome (ISCLS), is a rare, relapsing-remitting disorder featuring the abrupt extravasation of fluids and proteins into peripheral tissues, which in turn leads to hypotensive shock, severe hemoconcentration, and hypoalbuminemia. The specific leakage factor(s) and pathways in ISCLS are unknown, and there is no effective treatment for acute flares. Here, we characterize an autonomous vascular endothelial defect in ISCLS that was recapitulated in patient-derived endothelial cells (ECs) in culture and in a mouse model of disease. ISCLS-derived ECs were functionally hyperresponsive to permeability-inducing factors like VEGF and histamine, in part due to increased endothelial nitric oxide synthase (eNOS) activity. eNOS blockade by administration of N(γ)-nitro-l-arginine methyl ester (l-NAME) ameliorated vascular leakage in an SJL/J mouse model of ISCLS induced by histamine or VEGF challenge. eNOS mislocalization and decreased protein phosphatase 2A (PP2A) expression may contribute to eNOS hyperactivation in ISCLS-derived ECs. Our findings provide mechanistic insights into microvascular barrier dysfunction in ISCLS and highlight a potential therapeutic approach.

Protecting cardiomyocytes from hypoxia-reoxygenation injury, empaglifozin and liraglutide alone or in combination?

Empagliflozin, a sodium-dependent glucose co-transporter 2 (SGLT2) inhibitor, and liraglutide, a GLP-1 receptor (GLP-1R) agonist, are commonly recognized for their cardiovascular benefits in individuals with type 2 diabetes (T2D). In prior studies, we have demonstrated that both drugs, alone or in combination, were able to protect cardiomyocytes from injury induced by diabetes. Mechanistic investigations also suggested that the cardioprotective effect may be independent of diabetes In this study, we utilized a hypoxia-reoxygenation (H/R) model to investigate the cardiovascular benefits of SGLT2 inhibitor empagliflozin and GLP-1 receptor (GLP-1R) agonist liraglutide, both alone and in combination, in the absence of T2D. Our hypothesis was that empagliflozin and liraglutide, either individually or in combination, would demonstrate cardioprotective properties against H/R-induced injury, with an additive and/or synergistic effect anticipated from combination therapy. In this study, the cardiac muscle cell line, HL-1 cells, were treated with vehicle, empagliflozin, liraglutide, or a combination of the two drugs. The cells were then subjected to a hypoxia-reoxygenation (H/R) protocol, consisting of 1 h of hypoxia followed by 24 h of reoxygenation. The effects of the treatments on cytotoxicity, oxidative stress, endothelial nitric oxide synthase (eNOS) activity, phospho-protein kinase C (PKC) beta and phospho-eNOS (Thr495) expression were subsequently evaluated at the end of the treatments. We found that H/R increased cytotoxicity and reduces eNOS activity, empagliflozin, liraglutide or combination treatment attenuated some or all of these effects with the combination therapy showing the greatest improvement. Empagliflozin, liraglutide or combination of these two have cardioprotective effect regardless of diabetes. Cardioprotective effects of SGLT2 inhibitor and GLP-1R agonist is additive and synergistic.

In Vivo Study on Doxycycline Protective Mechanisms during Myocardial Ischemia Injury in Rats.

The fact that during myocardial ischemia/reperfusion (I/R) injury, myosin light chain 1 (MLC1) and troponin I (TnI) are degraded by matrix metalloproteases activity has already been well established in both in vitro and ex vivo studies. However, I/R injury is a complex issue based on several overlapping mechanisms. Increased activity of myosin light chain kinase and nitric oxide synthase due to oxidative stress leads to post-translational modifications of MLC1, thus leading to the increased degradation of these proteins. Wistar rats were subjected to left anterior descending coronary artery occlusion. To measure the pharmacological effect of doxycycline, transthoracic echocardiography as well as biochemical tests, concentrations of TnI, LDH, MLC1, MMP-2 and MMP-9 were performed. Gelatinize activity and cytotoxicity level were also assessed; Results: I.p., administration of doxycycline before LAD occlusion surgery increased TnI and LDH content in the heart and decreased cytotoxicity. A reduction of MMP-2 and MMP-9 concentration and MMP-2 activity after administration of Doxy was also observed, as well as improvement in echocardiographic parameters just 7 days after surgery. Inhibition of MMPs by doxycycline, in vivo, may serve as a protective agent in future therapy.

The acute neurotoxicity of inorganic mercury in Mactra chinensis philippi

Inorganic mercury (IHg) is hazardous to marine organisms especially resulting in neurotoxicity, bivalves are sensitive to pollutants as “ocean sentinel”, but data on the neurotoxicity of IHg in bivalves are sparse. So we chosed M. chinensis philippi with typical neural structures in bivalves to investigate the neurotoxicity of IHg, which could be helpful to understand the specificity of neural regulation and the response characteristics of bivalves. After acute exposed to IHg (HgCl2) for 24 h, the metabolites of ganglion tissues in M. chinensis philippi were evaluated using 1H-nuclear magnetic resonance based metabolomics; Ca2+, neurotransmitters (nitric oxide, glutamate, acetylcholine) and related enzymes (calcineurin, nitric oxide synthase and acetylcholinesterase) were measured using biochemical detection. Compared to the control group, the levels of the nitric oxide (81.04 ± 12.84 μmol/g prot) and acetylcholine (30.93 ± 12.57 μg/mg prot) in M. chinensis philippi of IHg-treated were decreased, while glutamate (2.11 ± 0.61 mmol/L) increased significantly; the activity of nitric oxide synthase (679.34 ± 135.33 U/mg prot) was increased, while acetylcholinesterase (1.39 ± 0.44 U/mg prot) decreased significantly, and the activity of calcineurin (0.52 ± 0.02 U/mg prot) had a statistically insignificant increasing tendency. The concentration of Ca2+ (0.92 ± 0.46 mmol/g prot) in the IHg-treated group was significantly higher than that in the control group. OPLS-DA was performed to reveal the difference in metabolites between the control and IHg-challenged groups, the metabolites of glucose, glutamine, inosine, succinate, glutamate, homarine, and alanine were sensitive to IHg, subsequently metabolic pathways that were affected including glucose metabolism, glutamine metabolism, nucleotide metabolism, Krebs cycle, amino acid metabolism and osmotic regulation. In our study, IHg interfered with metabolites in M. chinensis philippi, thus the corresponding metabolic pathways were changed, which influenced the neurotransmitters subsequently. Furthermore, Ca2+overload affected the synthesis or degradation of the neurotransmitters, and then the altered neurotransmitters involved in changes in metabolic pathways again. Overall, we hypothesized that the neurotoxic effects of IHg on bivalve were in close contact with metabolism, neurotransmitters, related enzymes and Ca2+, which could be effective neurotoxic biomarkers for marine environmental quality assessment, and also provide effective data for the study of the regulatory mechanism of the nervous system in response to IHg in bivalves.

Effects of Pamelo Orange Peel (Citrus maxima) Ethanol Extract on Macroscopic Kidney and Heart of Hypertensive Rats

Background: Hypertension, characterized by elevated blood pressure (≥140/90 mmHg), leads to kidney and heart damage. Hypertension causes increased heart rate, heart enlargement, risk of heart failure, and damage to kidney blood vessels. One way to treat hypertension is by administering drugs such as herbal medicines. Pamelo oranges (Citrus maxima) are starting to be developed in the treatment of diseases. The ethanol extract of pomelo orange peel (EEKJP) contains flavonoid compounds which have antihypertensive activity as a natural Angiotensin Converting Enzyme (ACE) inhibitor, diuretic, increases Nitric Oxide Synthase (NOS) activity and activates Endothelium Derived Relaxing Factor (EDRF). Objectives: This study aims to examine the effect of ethanol extract of pomelo orange peel on the macroscopic features of the heart and kidneys of hypertensive rats (Rattus norvegicus). Methods: This research uses The Posttest-Only Control Group Design. Thirty rats were divided into six groups, namely naive control, negative control (NaCMC 1%), positive control (Captopril 0,45 mg/200 gramBB), EEKJP 100 mg/KgBW group, EEKJP 150 mg/KgBW group, and EEKJP 200 mg/KgBW group. Hypertension condition through induction with prednisone 1.5 mg/KgBW and NaCl 2% for 21th days. The test preparation was administered orally for 14th days. Next, all rats were dissected to remove the heart and kidney organs for macroscopic observations. Results: The results of the study showed that ethanol extract of pomelo (Citrus maxima) orange peel had a varied effect on the macroscopic appearance of the heart and kidneys of rats with hypertension. The heart organ shows structural improvements, while the kidneys have not shown any improvement. Conclusions: Extract with a dose of 100 mg/KgBW has no changes in the macroscopic appearance of the heart so it is thought to be able to repair damage to the heart organ.

Effect of hyperbaric oxygen in hepatopulmonary syndrome: an innovative experimental study.

This study aimed to analyze the effect of hyperbaric oxygen treatment (HBOT) in hepatopulmonary syndrome (HPS). Five-month-old female Wistar-Albino rats were randomly divided into three groups: Group I, the control group; Group II, the cirrhosis group; and Group III, the cirrhosis group + HBOT group. Rats were exposed to HBO sessions (2.4 atm./60 min) for 20 days. Animals were sacrificed 24 hours after the last HBO session. Biochemical analysis, oxygenation parameters, NO and NO synthase (NOS) levels, histopathological changes in the liver and lungs, and pulmonary artery diameter were measured. A total of 24 rats (10 rats were included in Group I, six rats in Group II, and eight rats in Group III) weighing 220-250 g were included in the study. Significant differences were observed for NO and NOS (9.10±1.05 to 12.17±1.85 μmol/L, p<0.05 and 0.46±0.31 to 1.17±0.39 U/ml, p<0.05, respectively) at baseline and day 36 only in group II. Inflammatory cell infiltration and bronchial injury were significantly increased in group II compared to group I (p=0.007 and p=0.008, respectively) but not in group III (p=0.266 and p=0.275, respectively). Pulmonary artery diameter was significantly lower in group III compared with group II at all sites in both lungs (p<0.05). HBOT may be a promising treatment for HPS by reducing NO and NOS activity, perialveolar arteriolar dilation, lung inflammation, and injury and guiding future clinical trials.

The activation of endothelial nitric oxide synthase, induced by calcium influx plays a crucial role in regulating endothelial hyperpermeability caused by ultrasound-targeted microbubble cavitation

Ultrasound-targeted microbubble cavitation (UTMC) plays a crucial role in improving drug delivery across the endothelial barrier. For successful application of UTMC in clinic, an understanding of molecular mechanisms involved is essential. Here, we hypothesized that Ca2+ and endothelial nitric oxide synthase (eNOS) pathways regulate UTMC-induced endothelial hyperpermeability. We used human coronary artery endothelial cells seeded on transwell inserts, exposed to microbubbles and ultrasound (frequency 1 MHz; PNP 250 kPa; pulse length 10 μs; pulse interval 10 ms; treatment duration 10 s). UTMC caused cellular influx of Ca2+, which was inhibited by blocking mechanosensitive channels (p &amp;lt; 0.0001) using GsMTx4. Knockdown of Piezo1 using siRNA showed similar effects. UTMC-induced Ca2+ influx activated eNOS and enhanced nitric oxide production, which was necessary for UTMC-induced hyperpermeability. Our data suggest that UTMC induces a Ca2+ influx-dependent increase in S-nitrosylation: An increase in S-nitrosylation was observed on both β-catenin and VE-cadherin after UTMC, potentially contributing to the destabilization of adherens junctions that normally maintain barrier integrity. Our study explains the role of Ca2+ influx, eNOS activation, and enhanced S-nitrosylation of adherens junction proteins in the regulation of endothelial hyperpermeability. Further investigation of these pathways will aid in clinical translation and optimization of UTMC for delivering cell-impermeant drugs.

The Roles of Potassium Channels and Nitric oxide in the Modulation of Apelin induced-relaxation in Isolated Diabetic Rat Aorta

Diabetes is associated with endothelial dysfunction, which impairs blood vesselscapacity to maintain vascular tone. Apelin is an adipocyte-produced relaxing factor that has endothelium-dependent and nitric oxide (NO)-mediated vasorelaxant effects. The current study investigated how streptozotocin (STZ)-induced type one diabetes modulates the mechanisms involved in aortic vascular response to apelin, focusing on the role of potassium channels and endothelial derived relaxing factors (EDRF). In this study, precontracted rat thoracic aortic segments were pre-incubated with the NO inhibitor, cyclooxygenase (COX) inhibitor and potassium channels blockers including: non-selective calcium-activated potassium channel, big conductance calcium-activated potassium channels (BKca), intermediate conductance calcium activated potassium channels (IKca), delayed inward rectifier potassium channels (Kir), adenosine triphosphates-sensitive potassium channels (KATP) and voltage sensitive potassium channels (Kv) blockers, then cumulative concentrations of apelin were applied to each group in both non-diabetic and diabetic conditions. The statistical analysis between diabetic and non-diabetic groups revealed that endothelial impairment induced by diabetes in rat thoracic aorta remarkably attenuated the vascular responses to apelin. An important new finding in this study was that almost all potassium channels blockers noticeably P&lt;0.001 increased apelin efficacy with relatively no changes in the peptide potency. However, in diabetic aortic segments, the non-selective Kca, BKca blockers, NO inhibitor and COX inhibitor reversed vascular responses to apelin, but Kir, KATP and Kv blockers significantly reduced vascular responses to apelin in comparison to control rats. It is worth noting that diabetes did not only alter the peptide potency in these experimental groups but also significantly increased the maximum responses when Kca and BKca blockers preincubated. In conclusion, our findings shed light on the mechanisms behind diabetes-induced aortic artery hypo-reactivity to apelin which involve the inhibition of endothelial NO synthase activities and decreased contribution of Kca, BKca, IKca, Kv, Kir and KATP channels.

Functional deterioration of vascular mitochondrial and glycolytic capacity in the aortic rings of aged mice

Vascular ageing is associated with increased arterial stiffness and cardiovascular mortality that might be linked to altered vascular energy metabolism. The aim of this study was to establish a Seahorse XFe96 Analyzer-based methodology for the reliable, functional assessment of mitochondrial respiration and glycolysis in single murine aortic rings and to validate this functional assay by characterising alterations in vascular energy metabolism in aged mice. Healthy young and old C57BL/6 mice were used for the analyses. An optimised setup consisting of the Seahorse XFe96 Analyzer and Seahorse Spheroid Microplates was applied for the mitochondrial stress test and the glycolysis stress test on the isolated murine aortic rings, supplemented with analysis of NAD content in the aorta. To confirm the age-dependent stiffness of the vasculature, pulse wave velocity was measured in vivo. In addition, the activity of vascular nitric oxide synthase and vascular wall morphology were analysed ex vivo. The vascular ageing phenotype in old mice was confirmed by increased aortic stiffness, vascular wall remodelling, and nitric oxide synthase activity impairment. The rings of the aorta taken from old mice showed changes in vascular energy metabolism, including impaired spare respiratory capacity, maximal respiration, glycolysis, and glycolytic capacity, as well as a fall in the NAD pool. In conclusion, optimised Seahorse XFe96-based analysis to study energy metabolism in single aortic rings of murine aorta revealed a robust impairment of functional vascular respiratory and glycolytic capacity in old mice linked to NAD deficiency that coincided with age-related aortic wall remodelling and stiffness.

Effects of Dietary Selenium Yeast Supplementation on Lactation Performance, Antioxidant Status, and Immune Responses in Lactating Donkeys.

Donkey milk is a traditional medicinal food with various biological activities. However, its production is very low, and lactating donkeys often experience oxidative stress, leading to a further decline in milk yield. In this study, we supplemented the diets of lactating donkeys with yeast selenium (SY) to investigate its effects on lactation performance, antioxidant status, and immune responses, and we expected to determine the optimum additive level of SY in the diet. For this study, 28 healthy lactating Dezhou donkeys with days in milk (DIM, 39.93 ± 7.02 d), estimated milk yield (EMY, 3.60 ± 0.84 kg/d), and parity (2.82 ± 0.48) were selected and randomly divided into 4 groups of 7 donkeys in each: Group SY-0 (control), Group SY-0.15, Group SY-0.3, and Group SY-0.5, with selenium supplementation of 0, 0.15, 0.3, and 0.5 mg of Se/kg DM (in form of SY) to the basal diet, respectively. The results showed a dose-dependent increase in milk yield, milk component yield, milk protein production efficiency, milk production efficiency, the activities of glutathione peroxidases (GSH-Px), catalase (CAT), and total antioxidant capacity (T-AOC), as well as the content of serum interleukin-10 (IL-10), white blood cells (WBC), lymphocytes (LYM), red blood cells (RBC), hematocrit, plasma selenium, and milk selenium. Conversely, it presented a dose-dependent decrease in the activity of nitric oxide synthase (iNOS) and the contents of malondialdehyde (MDA), reactive oxygen species (ROS), nitric oxide (NO), interleukin-1β (IL-1β), interleukin-6 (IL-6), and interferon-γ (IFN-γ). In conclusion, the results confirmed that dietary supplementation with SY can improve lactation performance, antioxidant status, and immune responses in lactating donkeys, and the recommended dose of SY was 0.3 mg/kg.

Strain-specific responses of Penaeus vannamei to two Enterococcus faecium strains supplementation: A trade-off between growth and immunity

Probiotic properties are highly species- or even strain- specific. Strain-specific responses of growth performance, non-specific immunity, disease resistance, and intestinal microbiota in Penaeus vannamei to two Enterococcus faecium strains supplementation were investigated in this study. Basal diet (control, CON) was supplemented with E. faecium HK and LYB at the dose of 1 × 1010 CFU / kg (HK group) and 1 × 1011 CFU / kg (LYB group), respectively. The results indicated that the HK and LYB groups exhibited significant enhancements in growth performance, non-specific immunity, and disease resistance of shrimp against Vibrio parahaemolyticus compared to the control (P < 0.05). However, the specific growth rate of shrimp in the LYB group was significantly better than that in the HK group (P < 0.05). Furthermore, the HK group showed significant increases in phenoloxidase, total nitric oxide synthase activities, lysozyme content in the serum, as well as the relative expression levels of proPO, LGBP, Imd, Relish, and eIF4E2 genes in the hepatopancreas compared to the LYB group (P < 0.05). These results suggested the strain HK exhibited better non-specific immunity efficiency while the strain LYB exerted better growth enhancement in shrimp. Dietary both of strain HK and LYB significantly altered microbial community structure (P < 0.05), and the strain HK significantly improved intestinal microbial diversity in shrimp. The relative abundance of Rubritaleaceae and Rhodobacteraceae were significantly increased, whereas those of facultative anaerobes and potential pathogens (i.e., Vibrionaceae, Flavobacteriaceae and Erysipelotrichaceae, etc.) were reduced in response to dietary supplementation of E. faecium HK and LYB. Furthermore, dietary both of strain HK and LYB could promote intestinal microbial community stability by increasing average connectivity, cooperation interactions, the number of generalists within the network. When growth performance and intestinal microbial homeostasis of shrimp are considered, E. faecium LYB might be better than the strain HK in shrimp farming.