L-arginine Research Articles

L-Arginine, as an Important Metabolic Biomarker, Participates in the Pathological Process of Chronic Obstructive Pulmonary Disease

Aim: Chronic obstructive pulmonary disease (COPD) is one of the most widespread diseases, its pathogenesis is very complex and unclear. The purpose of this study was to find the new biomarkers of COPD and elucidate its role in the pathogenesis and treatment of COPD. Methods: 221 patients with COPD and 60 healthy people were enrolled in the study. Non-targeted analysis of metabolites in plasma of COPD patients and healthy people were performed by ultra-high performance liquid chromatography (UPLC) and quadrupole time-of-flight mass spectrometry (TOF-MS). The differential metabolites were analyzed and identified by multivariate analysis between healthy people and COPD patients. The role and mechanisms of the differential metabolic biomarkers in COPD were investigated and verified with COPD rats, arginosuccinate synthetase 1(ASS-l) KO mice and bronchial epithelial cells (BECs) in vivo and in vitro. Meanwhile, whether the differential biomarkers can be the potential treatment targets for COPD was also investigated. Results: 85 differentials metabolites were identified between healthy people and COPD patients by metabonomics. L-arginine (LA) was the most obvious differential metabolite among the 85 metabolites. At the same time, it was found that LA had protective effects on COPD with in vivo and in vitro experiments. Silencing ASS-1, which regulates LA metabolism, and α-methy-DL-aspartic (NHLA), an ASS-1 inhibitor, canceled the protective effect of LA on COPD. The mechanism of LA in COPD was related to the inhibition of ROS/NLRP3/NF-κB signaling pathway. Conclusion: L-arginine (LA) as a key metabolic marker is identified in COPD patients. LA has a protective effect on COPD, its mechanism is related to the regulation of ROS/NLRP3/NF-κB signaling pathway. LA may be a novel target for the treatment of COPD. Funding Information: This research was supported by National Natural Science Foundation of China (81400800). Declaration of Interests: The authors declare that they have no conflict of interest. Ethics Approval Statement: All patient experiments were performed under the guidance of the Helsinki Declaration and approved by the Research Council of Affiliated Nanjing Hospital of Nanjing University of Chinese Medicine (KY2017019). All animal experiments were performed in accordance with the principles of the Guide for the Care and Use of Laboratory Animals published by the U.S. National Institutes of Health (NIH Publications, eighth edition, 2011) and were approved by the Research Council and Animal Care and Use Committee of Affiliated Nanjing Hospital of Nanjing University of Chinese Medicine and Army Medical Center, Army Medical University.

Multifunctional l-arginine-based magnetic nanoparticles for multiple-synergistic tumor therapy.

Tumor therapy is facing the big challenge of insufficient treatment. Here, we report high-intensity focused ultrasound (HIFU)-responsive magnetic nanoparticles based on superparamagnetic iron oxide (SPIO, Fe3O4 NPs) as the shell and l-arginine (LA) as the core entrapped by poly-lactide-co-glycolide (PLGA) nanoparticles (Fe3O4@PLGA/LA NPs) for synergistic breast cancer therapy. These NPs can significantly enhance therapeutic performance due to their enhanced accumulation and prolonged retention at the tumor site under magnetic guidance. The Fe3O4@PLGA/LA NPs exhibited synergistic therapeutic effects by the rational combination of HIFU-based tumor ablation and nitric oxide (NO) assisted antitumor gas therapy. Both Fe3O4 NPs and LA could be released rapidly under HIFU irradiation, where Fe3O4 NPs can promote HIFU-based tumor ablation by changing the acoustic properties of the tumor tissues and LA can spontaneously react with hydrogen peroxide (H2O2) in the tumor microenvironment to generate NO for gas therapy. Moreover, Fe3O4 NPs can react with H2O2 to produce highly reactive oxygen-containing species (ROS) to accelerate the oxidation of LA and the release of NO. This novel strategy showed synergistic tumor growth suppression as compared with individual HIFU therapy or gas therapy. This can be attributed to the rational design of multifunctional NPs with magnetic targeting and multi-modality imaging properties.

Near-infrared light triggered photodynamic and nitric oxide synergistic antibacterial nanocomposite membrane

• NO exhibits the complementary advantage in enhancing the PDT antibacterial efficacy. • The system can avoid the shallow penetrability of short-wavelength light. • ROS/NO release can be controlled by single NIR, realizing on-demand sterilization. • The membrane can effective prevent inflammation and accelerate the wound healing. As an emerging bactericidal strategy, photodynamic therapy (PDT) exhibits great potential to combat various pathogenic infections, but its antibacterial efficacy may be compromised, generally owing to its shallow penetrability of short-wavelength (UV/Vis) light as well as short diffusion length and lifespan of the generated reactive oxygen species (ROS). Herein, we present a method for developing a nitric oxide (NO)-assisted PDT nanocomposite membrane with significantly enhanced bactericidal performances, upon a single near-infrared (NIR) light irradiation. Hierarchically structured nanoparticles (UCNP@PCN), composed of upconversion nanoparticles (UCNPs) and porphyrinic MOFs (PCN-224) are initially prepared. After being doped with l -arginine (LA), the nanoparticles are incorporated into polyvinylidene fluoride (PVDF) matrix to get electrospun nanocomposite membrane (UCNP@PCN@LA-PVDF). Upon NIR light irradiation (980 nm), this UCNP@PCN@LA-PVDF can generate sufficient ROS, which not only acts as main bactericidal agent in PDT but also induces the loaded LA to produce NO, eventually realizing the NO-assisted PDT antibacterial behavior. The generated NO exhibits a larger sterilization area as compared to that of the ROS, demonstrating a vital complementary advantage in facilitating PDT antibacterial efficacy as proven in vitro and in vivo tests. This type of nanocomposite membrane may find unique biomedical applications where both highly enhanced PDT antibacterial effects and deep penetration of NIR light are desired.

Protective effects of myocardium-targeted nanoparticles loaded L-arginineon on sepsis-induced myocardial injury

To prepare primary cardiomyocyte (PCM) specific peptide-conjugated mesoporous silicon nanoparticles (MSN) with L-arginine (LA) as a core (PCM-MSN@LA), and evaluate its specific protective effect on septic myocardium. PCM-MSN@LA was prepared by condensation reaction, the characterization of PCM-MSN@LA, the amount of LA modification and release was detected, and the phagocytosis of PCM-MSN@LA and its affinity to myocardial tissue was observed. (1) Experiment one: SD neonatal rat cardiomyocytes were divided into control group (Con group), lipopolysaccharide (LPS) group, MSN@LA/LPS group and PCM-MSN@LA/LPS group. The LPS group was stimulated with 5 mg/L LPS for 16 hours, while the MSN@LA/LPS group and PCM-MSN@LA/LPS group were treated with 5 mg/L LPS and 25 mg/L LA-containing nanoparticles (MSN@LA and PCM-MSN@LA) for 16 hours. Cell viability and reactive oxygen species (ROS) production levels were detected. Apoptosis was observed via terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling method (TUNEL). Western Blot was used to detect the changes in endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS) proteins. (2) Experiment two: 64 healthy male C57BL/6 mice were divided into Sham group, LPS group, MSN@LA/LPS group and PCM-MSN@LA/LPS group by random number table method, 16 mice in each group. LPS group were injected 50 mg/kg LPS intraperitoneally. MSN@LA/LPS group and PCM-MSN@LA/LPS group were injected with 0.5 mg/kg MSN@LA and PCM-MSN@LA via tail vein immediately after intraperitoneal injection of LPS. Eight animals in each group were used to observe the 24-hour survival rate, and the other 8 mice were used to detect cardiac function by echocardiography at 12 hours after operation; mRNA expressions of interleukin (IL-1, IL-6) and tumor necrosis factor-α (TNF-α) were measured by real-time fluorescent quantitative polymerase chain reaction (RT-qPCR). PCM-MSN@LA was spherical, with particle size of about 180 nm, Zeta potential of about -21 mV, with LA loaded. The amount of LA modification and release rate were 12.3% and 24.3%, respectively. Cell phagocytosis experiments showed that PCM-MSN@LA had the targeting ability of cardiomyocytes and myocardial tissue. Experiment one: after LPS stimulation of myocardial cells, cell viability decreased, while ROS generation, apoptosis, eNOS and iNOS protein expressions increased. Compared with LPS group, MSN@LA/LPS group and PCM-MSN@LA/LPS group had higher cell viability, reduced ROS levels and apoptosis, increased expressions of eNOS and iNOS. PCM-MSN@LA/LPS group changed the above effect further than MSN@LA/LPS group [cell viability (A value): 0.51±0.08 vs. 0.41±0.03, ROS (relative fluorescence intensity): 28 450±1 941 vs. 35 628±2 551, TUNEL positive cells/total cells: 0.27±0.03 vs. 0.35±0.04, eNOS/β-Tubulin: 1.467±0.046 vs. 1.201±0.131, iNOS/β-Tubulin: 1.700±0.033 vs. 1.577±0.068, all P < 0.05]. Experiment two: the number of 24-hour survive in MSN@LA/LPS group and PCM-MSN@LA/LPS group were higher than LPS group (number: 2, 4 vs. 1, P values were 0.36 and 0.03 respectively). Compared with Sham group, the cardiac function of LPS group was significantly inhibited and the mRNA expression of inflammatory factors increased. The PCM-MSN@LA/LPS group had higher left ventricular ejection fraction (LVEF) and left ventricular short-axis shortening rate (LVFS) than LPS group, and lower mRNA expressions of IL-1, IL-6, and TNF-α mRNA [LVEF: 0.456±0.019 vs. 0.337±0.017, LVFS: (21.97±1.78)% vs. (15.53±1.67)%, IL-1 mRNA (2-ΔΔCT): 169.22±8.95 vs. 189.79±6.79, IL-6 mRNA (2-ΔΔCT): 19.90±1.60 vs. 23.74±1.45, TNF-α mRNA (2-ΔΔCT): 8.21±0.81 vs. 11.00±1.48, all P < 0.05]. There was no significant difference in each index between the MSN@LA/LPS group and LPS group. PCM-MSN@LA with myocardial targeting characteristic significantly increased the activity of myocardial cells, down-regulated the expression of inflammatory factors and the production of ROS, alleviated cardiac insufficiency in sepsis, and achieved the targeted treatment of myocardial injury in sepsis.

A Systematic Review on Urinary Biomarkers for Early Diagnosis of Alzheimer’s Disease (AD)

Alzheimer’s disease (AD) is a neurodegenerative disease that commonly affects the older population whose symptoms are only visible during the later stage which renders the available treatment ineffective. Our study attempts to provide a solution to this problem by identifying urinary biomarkers that could be used in the first-line screening of a larger population for AD before analysing with more sophisticated blood and CSF based biomarkers, which provide high sensitivity on comparison. A systematic review was performed using the keywords “Alzheimer”, “urine”, “biomarkers” and “metabolomics” following the PRISMA criteria, to identify urinary biomarkers for the early diagnosis of Alzheimer’s disease. From the performed study, three metabolites were identified namely 5-hydroxy indole acetic acid, L-arginine and allantoin as biomarkers whose level was altered in AD samples compared to controls. In AD, 5-hydroxy indole acetic acid level was downregulated in urine probably because of the extensive serotonergic denervation that has been observed in the AD brain. Increased levels of L-arginine in the brain which act as a precursor to nitric oxide due to the action of NO synthase might potentially lead to neurotoxicity when present in excess, and is also known to be in synergy with ROS. Increased levels of allantoin in urine is due to the action of increased ROS in the system reacting with uric acid. Here, we provide an overview of all the reported metabolites obtained from the search, by discussing their influence in AD pathology. This study identified three metabolites in urine that could function as potential biomarkers for AD based on significant changes observed between disease and control samples, along with its recurrence and commonality in different models namely mice and human. However, longitudinal and cross-sectional follow-up studies are required for the validation of these biomarkers.

Biomimetic nano-NOS mediated local NO release for inhibiting cancer-associated platelet activation and disrupting tumor vascular barriers

Platelets attribute to the hypercoagulation of blood and maintenance of the tumor vascular integrity, resulting in limited intratumoral perfusion of nanoparticle into solid tumors. To overcome these adversities, we herein present an antiplatelet strategy based on erythrocyte membrane-enveloped proteinic nanoparticles that biomimic nitric oxide synthase (NOS)with co-loading of l-Arginine (LA) and photosensitizer IR783 for local NO release and inhibition of the activation of tumor-associated platelets specifically, thereby enhancing vascular permeability and accumulation of the nanoparticles in tumors. A cRGD-immobolized membrane structure is constructed to actively target platelets and cancer cells respectively, through overexpressed integrin receptors such as integrin αIIbβ3 and αvβ3, accelerating the inhibition of platelet activation and endocytosis of nanoparticles by tumor cells. Bio-mimicking the arginine/NO pathway in vivo, synergistical delivery of LA and IR783 enables LA molecules readily oxidize to NO with O2 that is mediated by activated IR783, the resulted NO not only retards the activity of platelets to disrupt the vascular integrity of tumor but also enhances toxicity to cancer cells. In addition, NIR-controlled release localizes the NO spatiotemporally to tumor-associated platelets and prevents undesirable systemic bleeding substantially. The reduction of the hypercoagulable state is further demonstrated by the down-regulation of tissues factor (TF) expression in tumor cells. Our study describes a promising approach to combat cancer, which advances the biomimetic NOS system as the potent therapeutic forces toward clinic applications.

Blunted Cutaneous Thermal Reactivity in Black Women and the Relationship with Endothelin‐1 and L‐arginine

The black population (BL) has elevated rates of hypertension and cardiovascular disease relative to other populations. However, research specific to the mechanisms for these conditions in BL women (BW) remains remarkably devoid. Our group recently demonstrated impaired microvascular function in young, BL men (BM) and BW. Further, inhibition of oxidative stress from xanthine and NADPH oxidases restored microvascular function in BM, while no such effect was observed in BW suggesting divergent mechanisms of microvascular dysfunction between these populations. Two possible candidate mechanisms are heightened endothelin‐1 (ET‐1) activity and/or reduced L‐arginine (L‐ARG) bioavailability, both of which have been noted in BW, but not specifically linked to microvascular dysfunction. Therefore, this study tested the hypothesis that ET‐1 overactivity and/or L‐ARG insufficiency contribute to the blunted microvascular function observed in young, BW. To test this hypothesis, four intradermal microdialysis membranes were placed in the dorsal forearm of 4 white women (WW) and 6 BW (mean±SD; age: 22 ± 2 vs. 21 ± 3) and the cutaneous vascular conductance (CVC: cutaneous blood flow/mean arterial pressure) response to a standard local heating protocol was assessed. Following trauma resolution, each site received one of four, 30‐min infusions: lactated Ringer’s (control), BQ‐123 (500nM; ET receptor type A antagonist), BQ‐788 (300nM; ET receptor type B antagonist), or L‐ARG (10mM). After a 10‐min baseline at 33°C, skin temperature was elevated to 39°C for ~30‐min to assess local cutaneous thermal reactivity. L‐NAME (20mM) was then infused at all sites to inhibit nitric oxide (NO) synthase and quantify the NO contribution to the CVC response. Site‐specific maximal cutaneous blood flow was then determined via combined sodium nitroprusside (28mM) infusion and 43°C heating. The CVC response during each stage was calculated as a percent of site‐specific maximum (%CVCmax) while the NO contribution was calculated as a delta between the 39°C plateau and the L‐NAME nadir (Δ%CVCmax). During local heating, BW exhibited blunted CVC responses compared to WW (control: 35.3 ± 28.7 vs. 50.6 ± 8.1 %CVC‐max; BQ‐123: 41.6 ± 12.0 vs. 64.5 ± 9.2 %CVCmax; BQ‐788: 25.9 ± 18.9 vs. 59.5 ± 13.9 %CVCmax; L‐ARG: 29.6 ± 12.1 vs. 54.6 ± 11.9 %CVCmax; respectively; main effect: P = 0.03). BW also exhibited a reduced NO contribution to vasodilation relative to WW (control: 19.4 ± 8.6 vs. 37.6 ± 7.4 Δ%CVCmax; BQ‐123: 30.8 ± 11.8 vs. 47.8 ± 7.6 Δ%CVCmax; BQ‐788: 17.3 ± 14.7 vs. 44.0 ± 14.2 Δ%CVCmax; L‐ARG: 21.5 ± 9.2 vs. 40.0 ± 12.3 Δ%CVCmax; respectively; main effect: P &lt; 0.01). No interactions were noted for either race‐by‐drug comparison (P &gt; 0.05). These preliminary data suggest that BW exhibit blunted NO‐mediated vasodilation to local heating compared to WW. However, individual ET‐1 receptor activity and reduced L‐ARG bioavailability do not appear to influence the blunted dilatory response.Support or Funding InformationResearch Support: ACSM, Texas ACSM, and The University of Texas at Arlington CONHI (JDA)

Insulinotropic and antidiabetic effects of β-caryophyllene with l-arginine in type 2 diabetic rats.

Beta-caryophyllene (BCP) is a flavoring agent, whereas l-arginine (LA) is used as a food supplement. They possess insulinotropic and β cell regeneration activities, respectively. We assessed the antidiabetic potential of BCP, LA, and its combination in RIN-5F cell lines and diabetic rats. Ex vivo studies were carried out for glucose uptake and absorption of the combination of BCP with LA. The results indicated that the combination of BCP with LA showed a significant decrease in glucose absorption and an increase in its uptake in tissues and also an increase in insulin secretion in RIN-5F cells. The combination treatment of BCP with LA showed a significant reduction in glucose, lipid levels, and oxidative stress in pancreatic tissue when compared with the diabetic group. Furthermore, the combination of BCP with LA normalized glucose tolerance and pancreatic cell damage in diabetic rats. In conclusion, the combinational treatment showed significant potentials in the treatment of type 2 diabetes mellitus. PRACTICAL APPLICATIONS: Type 2 diabetes mellitus is the most prevalent chronic metabolic disorder affecting a large population. Beta-caryophyllene is a CB2 receptor agonist shown to have insulinotropic activity. l-Arginine is a food supplement that possesses beta-cell regeneration property. The combination of BCP with LA could work as a potential therapeutic intervention, considering the individual pharmacological activities of each. We evaluated the antidiabetic activity of the combination of BCP with LA in diabetic rats using ex vivo and in vitro experimentations. Results from the study revealed that the combination of BCP with LA showed a significant (p<.001) reduction in glucose and lipid levels as compared to individual treatment. In vitro study also supports the diabetic potential of the combination of BCP with LA in the glucose-induced insulin secretion in RIN-5F cell lines. The study indicates a therapeutic approach to treat T2DM by BCP and LA combination as food and dietary supplement.

Clinical efficiency of exogenous L-arginine in patients with essential hypertension against the background of chronic obstructive pulmonary disease

Хроническое обструктивное заболевание легких (ХОЗЛ) и гипертоническая болезнь (ГБ) – одна из распространенных, ведущих и актуальных проблем практического здравоохранения. Цель работ ы – оценка клинической эффективности средства метаболической коррекции (Тивортин) в комплексном лечении больных хроническим обструктивным заболеванием легких при наличии гипертонической болезни. Материалы и методы. Обследовали 23 больных (основная группа) с диагнозом ГБ II стадии с уровнем артериальной гипертензии I–III степени и ХОЗЛ II стадии без клинически значимой сопутствующей патологии, средний возраст – 51,72 ± 1,22, с различным кардиоваскулярным риском, без адекватной систематической антигипертензивной терапии; 82,6 % – активные курильщики, индекс пачко-лет – 17,23 ± 2,69, на профессиональный фактор (производственный) указали 23,53 % обследованных. Все больные основной группы принимали L-аргинин аспартат в виде 4,2 % раствора внутривенно по 100 мл 1 раз в сутки (курс 10–12 дней) с последующим переходом на раствор для перорального применения по 10 мл 5 раз в сутки (курс 3 мес. ± 3 суток). Также обследовали (изначально и через 3 мес.) группу сравнения (n = 15, возраст – 49,15 ± 1,40 года), сопоставимую по клинико-демографическим показателям с основной группой. Обследованные из группы сравнения получали аналогичную традиционную терапию ГБ и ХОЗЛ без применения метаболитотропного препарата – экзогенного L-аргинина Тивортин. Диагностику ХОЗЛ и ГБ проводили на основании общепринятых критериев. Параметры качества жизни оценивали согласно «Краткого опросника оценки статуса здоровья» SF-36. Метаболизм глутатиона и состояние тиол-дисульфидного баланса изучали по содержанию окисленного и восстановленного глутатиона и активности ферментов – глутатион-S-трансферазы, глутатионредуктазы и глутатион пероксидазы в сыворотке крови. Содержание ST2, CASPASE-7 и CASPASE-9 в крови определяли с использованием соответствующих тест-систем ИФА. Результаты. Назначение L-аргинина способствовало подавлению оксидативного стресса и восстановлению тиол-дисульфидного баланса и, как результат вышеуказанных процессов, тормозило апоптоз в организме пациентов с коморбидностью. Уровень экспрессии белка ST2 после лечения пациентов с ГБ и ХОЗЛ Тивортином уменьшился в два раза, а компенсаторная возможность организма больного, которая заключается во включении кардиозащитного сигнального каскада предотвращения фиброза и ремоделирования сердца наиболее оптимальным путем будет реализована именно после проведения экспериментального лечения. Кроме регресса клинических симптомов, нормализации артериального давления и улучшения бронхиальной проходимости на фоне снижения уровня активности апоптотических маркеров, наблюдается восстановление качества жизни, как физического, так и психосоциального статуса. Выводы. Дополнительное назначение L-аргинина на фоне традиционной терапии ХОЗЛ и ГБ способствует более значимому и достоверному угнетению оксидативного стресса и восстановлению тиол-дисульфидного баланса и, как результат вышеуказанных процессов, тормозит интенсификацию процессов апоптоза у пациентов с указанной коморбидностью. Кроме регресса клинических симптомов, нормализации артериального давления и улучшения бронхиальной проходимости на фоне снижения уровня активности апоптотических маркеров, наблюдается достоверное восстановление качества жизни, как физического, так и психосоциального статуса.

NADPH oxidase participates in pancreatic injury in rats with acute hypertriglyceridemic pancreatitis by regulating Akt/GSK3 β pathway

Objective To investigate the aggravation of pancreatic tissue injury in rats with acute hypertriglyceridemic pancreatitis and the possible role of NADPH oxidase (NOX). Methods Thirty SPF rats were randomly (random number)divided into five groups: N group, H group, NLAP group, HLAP group and HAPO group. AMY, TG, TC and FFA levels were detected. The pathological changes of pancreas were observed under light microscope and the ultrastructural changes of pancreatic acinar cells were observed by TEM. Serum levels of MDA, SOD, IL-1β, TNF-α and LDH were detected. The expression of NOX4, p-Akt and p-GSK3β in pancreas was detected by immunofluorescence, and the expression of NF-κB and TNF-α in pancreas was detected by immunohistochemistry. Results Intraperitoneal injection of P-407 could significantly increase the levels of serum TG, TC and FFA in rats. After acute pancreatitis induced by L-Arg, the levels of serum AMY in the NLAP and HLAP groups were significantly increased, while Apocynin could significantly decrease the level of serum AMY. Compared with the NLAP group, the pathological injury of pancreatic tissue in the HLAP group was more serious, the level of inflammatory mediators was significantly increased, and the cell necrosis was more serious. After inhibiting NOX, the activation of Akt/GSK3β pathway was regulated and the pancreatic injury was improved. Conclusion In HTGP, NOX aggravates pancreatic injury by regulating the activation of Akt/GSK3 β pathway. Inhibition of NOX expression can play a protective role in pancreas injury of HTGP.. Key words: Hypertriglyceridemia; Acute pancreatitis; Pancreatic injury; NADPH oxidase; Oxidative stress

Effect of Chronic Nicotine Exposure on Maternal Renal Adaptations in Pregnant Rats: The Possible Role of Nitric Oxide

Abstract Background: Nicotine exposure during pregnancy contin-ues to be a widespread public health problem, impacting both fetal and postnatal health. Although the deleterious effects of nicotine on fetal development and the newborn have been extensively investigated, few studies have focused on its negative effects on the maternal adaptations to pregnancy especially relevant on renal functions. Aim of Study: To study the effects of chronic nicotine exposure on the maternal renal adaptations during pregnancy and the possible underlying mechanisms. Material and Methods: Thirty six adult virgin female albino rats, divided into two main groups, each subdivided into three subgroups; all received treatment for four weeks. Group I (virgin): Subdivided into; saline treated: Received daily subcutaneous saline injections, nicotine treated: Received daily nicotine bitartrate (1mg/kg) subcutaneous injections, combined with transdermal nicotine patches (5.2mg nico-tine/day) application, and nicotine and L-arginine treated: Received the same nicotine therapy plus 0.25% L-arginine added to drinking. Group II (pregnant): Subdivided into; saline treated: Received daily subcutaneous injections of saline (2 weeks prior to mating and 1 st two weeks of gestation), nicotine treated: Received daily subcutaneous injections of nicotine bitartrate (1mg/kg), with transdermal nicotine patches, and nicotine and L-arginine treated): Received same nicotine therapy plus 0.25% L-arginine added to drinking water. Results: Physiological effects of the pregnancy on renal function were significantly improved by L-argini ne. Similarly, nicotine exposure to virgin group produced a significant increase in serum and urinary Na+, significant decrease in renal total protein, nitric oxide with renal oxidative stress compared to their control group. Co-administration of nicotine and L-arginine to virgin group produced a significant decrease in serum Na+, urinary albumin and renal MDA levels, and significant increase in the urinary Na+ level, renal total protein, NO and GSH levels compared to the virgin nicotine group. Similarly, nicotine administration to pregnant group produced a significant increase in serum and urinary Na+, FENa, urinary albumin levels, together with significant de-crease in GFR, UFR and renal total protein, NO and GSH levels. While co-administration of nicotine and L-arginine to pregnant group produced a significant decrease in serum Na+, FENa, urinary albumin levels, with significant increase in the GFR, UFR and renal total protein, NO and GSH levels. Conclusion: We concluded that chronic nicotine exposure potentially impaired maternal renal adaptation to pregnancy which was improved greatly by L-arginine, implicating NO as crucial player.

NON-CONVENTIONAL APPROACHES FOR THE MANAGEMENT OF ANGINA

Angina is usually classified as a symptom of an underlying cardiovasculardisease which is one of the most common disorder that is affecting the human lifenow a days. It is presented as a throbbing chest pain that can radiate to left armand back due to ischemia of major vessel supplying blood to heart. Several drugclasses and their combination has long been used to treat angina for e.g. Nitrates,Nitrites, Calcium channel blockers, Beta blockers and sodium channel blockersto improve the demand vs supply ratio of oxygen so that the heart muscles canperform its function effectively. The increasing prevalence of disease andresulting resistance to conventional therapy has urged scientists to find otherways that can help in the management of this disease. Cardiovascular andconsequently angina is thus the focus of many studies. In this review a number ofstrategies and their associated mechanisms has been discussed which includeLife style modification, Yoga, Acupuncture therapy, Herbal treatment , L-arginine,L-carnitine, Omega 3 fatty acids, Gene therapy, Cell therapy, Chinese Medicine,and Interventions like Spinal cord Stimulation, Percutaneous coronaryintervention, Enhance external counter pulsation, Extracorporeal shockwavemyocardial revascularization, Transmyocardial laser revascularization,transcutaneous electrical nerve stimulation, percutaneous retrograde coronarysinus perfusion. Coronary sinus perfusion, Coronary sinus reducer, Videothoracoscopic sympathectomy (VTSY) may help in short term and long-termmanagement of angina

P6377Cardiopulmonary effects of nitric oxide supplementation in a model of chronic hypoxia pulmonary hypertension

Abstract Objective We previously demonstrated that the inhibition of phosphodiesterase type-5, an enzyme that degrades cGMP into inactive 5'-GMP, attenuates pulmonary remodeling and right ventricular (RV) hypertrophy (RVH) during exposure to chronic hypoxia (CH). The nitric oxide (NO) pathway is thought to play a major role in these changes. In this study, we investigate whether L-Arginine (L-ARG), a substrate of endothelial NO synthase (eNOS) and molsidomine (MOL), a NO donor, might alleviate the cardiovascular and pulmonary dysfunction led by CH. Methods Male rats (n=80; 10/group) were maintained in normoxic (21% O2) or hypoxic chambers (10% O2) for 14 days. Hypoxic rats were subdivided in four groups: untreated control, treated with L-ARG (45 mg/kg), eNOS inhibitor N-nitro-L-arginine methyl ester (L-NAME, 45 mg/kg) or MOL (15 mg/kg). Drugs were given daily in the drinking water. After sacrifice, we measured RV systolic pressure (RVSP), RV contractility (dP/dt), RVH, the lung/body weight ratio, the pulmonary vessels medial wall thickness, and the cardiac and pulmonary eNOS phosphorylation. Results Although CH increased RVSP, RV contractility and RVH, these increases were attenuated by L-ARG and MOL. Whereas L-ARG attenuated the RVH increase, MOL and L-NAME were ineffective. No treatment prevented the increase in lung/body weight ratio. Under all conditions, the lung tissue water content was unchanged, indicating no edema development. By contrast, CH rats developed a marked increase in medial wall thickness of small (0–100 mm) pulmonary arteries, while larger arteries were not affected. This increase was attenuated by L-ARG or MOL. Although CH decreased cardiac and pulmonary phosphorylated eNOS, L-ARG and MOL restored the normoxic level. Conclusions NO supplementation during CH attenuates RVSP, RVH and pulmonary remodeling, probably due to increased phosphorylation of eNOS. Despite normalizing RVSP, MOL does not influence RVH development.

Advances of nitric oxide and inducible nitric oxide synthase in asthma

Asthma is a chronic inflammatory respiratory disease characterized by variable airway obstruction, airway hyperresponsiveness, and airway remodeling.In the respiratory tract, nitric oxide(NO) is generated via oxidation of L-arginine that is catalyzed by inducible nitric oxide synthase(iNOS). In hypoxia-ischemia and inflammation processes, iNOS is induced to produce excessive NO, playing an important role in asthma, including the modulation of airway and vascular smooth muscle tone and the inflammation.This review focuses on recent research achievements regarding the relationship between NO and iNOS and asthma. Key words: iNOS; NO; Asthma

Arginine and tetrahydrobiopterin supplementation in rats with salt-induced blood pressure increase: minor hypotensive effect but improvement of renal haemodynamics.

High salt (HS) intake can lead to hypertension, probably the result of the predominance of vasoconstrictor reactive oxygen species over vasodilator nitric oxide (NO). We aimed to examine if the supposed NO deficiency and the resultant blood pressure increase could be corrected by supplementation of L-arginine, the substrate, and tetrahydrobiopterin (BH4), a co-factor of NO synthases. Wistar rats without known genetic background of salt sensitivity were exposed to HS diet (4%Na) for 10 or 26 days, without or with supplementation with oral L-arginine, 1.4 mg/kg b.w. daily, alone or together with intraperitoneal BH4, 10 mg/kg daily. Systolic blood pressure (SBP, tail-cuff method) was measured repeatedly and found to increase ~40 mmHg after 26 days; L-arginine and BH4 did not significantly attenuate this increase. At the end of chronic studies, in anaesthetized rats the diet- and treatment-induced changes in renal haemodynamics were assessed. HS diet selectively decreased (-30%, P < 0.03) the inner medullary blood flow (IMBF, laser-Doppler flux) without changing total or cortical renal perfusion. Arginine supplementation tended to raise all renal circulatory parameters, and distinctly increased IMBF, to 61% above the HS diet level (P < 0.05). In conclusion, unlike in confirmed genetically determined salt-dependent hypertension, L-arginine and BH4 supplementation failed to attenuate the SBP increase observed after exposure to HS diet. On the other hand, arginine increased total and regional renal perfusion, especially IMBF. This suggests that the delivery of arginine increased intrarenal NO synthesis, an action of renoprotective potential which presumably countered the harmful influence of the local tissue oxidative stress.

Research progress on nitric oxide depletion and its replacement therapy in intravascular hemolytic diseases

In the case of intravascular hemolysis in patients with hemolytic diseases such as paroxysmal nocturnal hemoglobinuria (PNH) and sickle cell disease (SCD), patients′ body can produce a large amount of free hemoglobin (FHb) and release intracellular arginase. FHb can rapidly scavenge nitric oxide (NO) and arginase can degrade L-arginine, which is substrate for NO synthesis. All together with the increased amount of reactive oxygen species (ROS) after hemolysis, NO appears to be depleted in the circulation, which results damages to endothelial and dysfunction of microcirculation, as well as eventually lead to acute and chronic impair to multiple organs. In recent years, with the in-depth study of the mechanisms beneath NO depletion in intravascular hemolytic disorders, the common pathological mechanisms of such diseases have been elucidated, and NO replacement therapy seems to be an all new approach. In view of this, this article reviews the research progress in the field of NO depletion and its replacement therapy in intravascular hemolytic diseases. Key words: Hemolytic disease; Nitric oxide; Depletion; Replacement therapy; Intravascular hemolysis

Molecular evidence of tissue remodeling in an animal model of heart failure.

Heart failure (HF) is the final common pathway of many cardiovascular diseases. Metalloproteinases and their inhibitors, such as MMP9 and TIMP-1, assist in maintaining the extracellular matrix, leading to tissue remodeling observed after HF. Previous studies have shown that L-Arginine (LA) appears to have beneficial effects for the treatment of HF, contributing to vasodilation, the reestablishment of the endothelial function and an increase in muscle contractile force. This study analyzed heart tissue remodeling in an animal model of HF induced by aortocaval fistula (ACF) and submitted to LA treatment. After 4 weeks of ACF, animals were treated with LA for 4 weeks (SHAM-LA, HF-LA) or for 8-12 weeks with saline (SHAM, HF8, HF12). Rats were euthanized and the hearts removed for histological processing. The samples were stained with Hematoxylin-Eosin (HE), Masson's Thichome (MT), or submitted to immunohistochemistry (IHC) for MMP9 and TIMP-1. Light microscopy analysis showed cardiac striated muscle without fibrosis in all experimental groups. Immunostaining of MMP9 and TIMP-1 were positive for all experimental groups. LA administration significatively reduced MMP9 content after HF. These data indicate molecular changes in metalloproteinases expression prior to tissue remodeling and point out LA as an adjuvant therapy to pharmacological treatment of patients with HF.

Mechanisms of Cannabinoid 2 receptor agonist JWH133-mediated modulations in cell calcium signals of mouse pancreatic acinar cells and its application for treatment of acute pancreatitis

Objective To evaluate the effect of JWH133 on acetylcholine (Ach)-induced Ca2+ oscillations, and to elucidate its mechanism and target. Methods Pancreatic acinar cells were isolated by enzymatic hydrolysis. Patch-clamp whole cell recording techniques were used to measure the effects of 10 μmol/L JWH133 on 10 nmol/L ACh-induced intracellular Ca2+ oscillations in pancreatic acinar cells acutely dissociated from wild-type (WT), and Cannabinoid 2 receptor (CB2R) knockout (KO) mice, and the pharmacological effects of JWH133 on the Ca2+ oscillations. The effect of 10 μmol/L JWH133 on the enhancement of Ca2+ oscillation induced by 10 mmol/L L-Arginine (L-Arg) was measured. The model of acute pancreatitis in mice was induced by L-Arg, and the histological structure, cell morphology and hemorrhagic necrosis were examined. Results The results showed that JWH133 could inhibit ACh-induced Ca2+ oscillations likely through CB2R. Patch-clamp recordings demonstrated that 10 μmol/L of JWH133 could reduce the 10 nmol/L ACh-induced Ca2+ oscillations current to (26.0±4.2)% (P 0.05, n=9). 10 μmol/L of JWH133 attenuated the enhancement of calcium oscillations current to (106.0±16.7)% (P<0.01, n=10) induced by 10 mmol/L L-Arg. In L-Arg acute pancreatitis model, JWH133 improved L-Arg -induced pancreatic pathological changes (P<0.05, n=5). Conclusion JWH133 inhibits intracellular calcium signals by selectively inhibiting extracellular CB2R. In L-Arg -induced acute mouse pancreatitis model, JWH133 significantly improves pathological changes. All these results suggest that JWH133 is a promising candidate for treatment of acute pancreatitis. Key words: Acute pancreatitis; Cannabinoid 2 receptor agonist; Calcium signals; Patch clamp

Exogenous l-ARGININE does not stimulate production OF NO or cGMP within the rat corporal smooth muscle cells in culture

Background and aimNitric oxide (NO) is the intracellular chemical responsible for initiating a penile erection. Despite conflicting clinical data, it continues to be publicized and promoted that orally administered l-arginine, the putative substrate for NO, enhances the erectile response presumably by stimulating NO production by the corporal tissues resulting in an increase in cGMP production. To shed light on this issue, an in vitro study was conducted to explore the effect of direct exogenous administration of l-arginine as well as its precursor and metabolite, l-citrulline, on the NO-cGMP pathway within the cavernosal smooth muscle (CSM) cell. Materials and methodsCSM cells obtained from 8 to 10 week old Sprague-Dawley rats were grown in Dulbecco media with 20% fetal calf serum and then incubated with or without l-arginine (L-ARG) or l-citrulline (L-CIT) in a time course and dose-response manner. Sildenafil (0.4 mM), IBMX (1 mM), l-NAME (3 μM), ODQ (5 μM) and Deta Nonoate (10 μM) were used as either inhibitors or stimulators of the NO-cGMP pathway. mRNA and protein were extracted and used for the determination of the phosphodiesterase 5 (PDE5). PDE5 activity was determined by luminometry. cGMP content was determined by ELISA. Nitrite formation, an indicator of NO production, was measured in the cell culture media by a colorimetric assay. The cationic (CAT-1) and neutral (SNAT-1) amino acid transporters for L-ARG and L-CIT, respectively, were determined by Western blot. ResultsWhen compared to untreated CSM cells, incubation with 0.25–4.0 mM of L-ARG or 0.3–4.8 mM of L-CIT anywhere between 3 and 24 h did not result in any additional nitrite or cGMP production. The addition of l-NAME, IBMX or ODQ to these L-ARG and L-CIT treated cells did not alter these results. L-CIT but not L-ARG increased PDE5 mRNA and protein content as well as the activity of the PDE5 enzyme. Both CAT-1 and SNAT-1 were expressed in the CSM cells. ConclusionsThis in vitro study demonstrates that exogenous administration of L-ARG or L-CIT failed to stimulate production of either NO or cGMP by the corporal CSM cells. A re-evaluation of the presumptive role of the exogenous administration of L-ARG in improving the synthesis of NO at least at the level of the CSM cells appears warranted.

The effects of glycine betaine and L-arginine on biochemical properties of pot marigold (calendula officinalis L.) under water stress

Pot marigold (Calendula officinalis L.) is widely used due to its various biological activities to treat diseases as an analgesic, anti-diabetic, anti-ulcer and anti-inflammatory agent. To ameliorate the adverse effects of water stress on this medicinal plant, foliar application of glycine betaine (GB) and L-arginine (LA) was used. For this purpose, water stress was applied at three levels (100%, 70% , and 40% field capacity (FC)), and foliar application was used at five levels (control, 50 mM GB, 100 mM GB, 1.5 mM LA, and 3 mM LA) as factorial based on completely randomized design. We measured phenol and flavonoid content, DPPH radical scavenging activity, superoxide dismutase (SOD) and phenylalanine ammonia-lyase (PAL) activity, and essential oil (EO) content and yield. Total phenol content in the interaction of 40% FC and GB 100 mM was higher than the other treatments. The highest and lowest total flavonoid content and DPPH radical scavenging activity were observed in the interaction of 40% FC and 100% FC, respectively. These variables at GB 100 mM were greater than the others. The highest SOD and PAL activity was found in the interaction of 40% FC and LA 3 mM/GB 100 mM. The content and yield of EO in the interaction of 70% FC and 100 mM GB were greater than other treatments. In sum, 70% of water stress did not significantly change the biochemical properties of C. officinalis, but 40% FC dramatically influenced the quality of the plant. GB 100 mM could stimulate the plant to activate its antioxidant systems under water stress and obtain the highest EO.