Displaying publications 21 - 40 of 113 in total

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  1. Nitric oxide production by a murine macrophage cell line (RAW264.7 cells) stimulated with Aggregatibacter actinomycetemcomitans surface-associated material
    Sosroseno W, Bird PS, Seymour GJ
    Anaerobe, 2011 Oct;17(5):246-51.
    PMID: 21736946 DOI: 10.1016/j.anaerobe.2011.06.006
    Nitric oxide (NO) may play a crucial role in the pathogenesis of periodontal disease and, hence, the aim of the present study was to test the hypothesis that Aggregatibacter actinomycetemcomitans surface-associated material (SAM) stimulates inducible nitric oxide synthase (iNOS) activity and NO production by the murine macrophage cell line RAW264.7. Cells were stimulated with untreated or heat-treated A. actinomycetemcomitans SAM and with or without pre-treatment with L-N(6)-(1-Iminoethyl)-lysine (L-NIL) (an iNOS inhibitor), polymyxin B, interferon-gamma (IFN-γ) and Interleukin-4 (IL-4), IL-10, genistein [a protein tyrosine kinase (PTK) inhibitor], bisindolylmaleimide [a protein kinase C (PKC) inhibitor], bromophenacyl bromide (BPB) [a phospholipase A(2) (PLA2) inhibitor] or wortmannin [phosphatidylinositol 3-kinase (PI-3K) inhibitor]. The iNOS activity and nitrite production in the cell cultures were determined. Untreated but not heat-treated A. actinomycetemcomitans SAM-stimulated both iNOS activity and nitrite production in RAW264.7 cells. L-NIL, IL-4, IL-10, genistein, bisindolylmaleimide, or BPB, suppressed but IFN-γ enhanced both iNOS activity and nitrite production by A. actinomycetemcomitans SAM-stimulated cells. Wortmannin and polymyxin B failed to alter both iNOS activity or nitrite production by A. actinomycetemcomitans SAM treated cells. Therefore, the present study suggests that a heat-sensitive protein constituent(s) of A. actinomycetemcomitans SAM stimulates both iNOS activity and nitrite production by RAW264.7 cells in a cytokine, PTK, PKC, and PLA(2) but not PI-3K-dependent fashion.
    Matched MeSH terms: Nitric Oxide Synthase Type II/antagonists & inhibitors; Nitric Oxide Synthase Type II/immunology; Nitric Oxide Synthase Type II/metabolism
  2. Fulltext Expression of Endothelin-1 and Endothelial Nitric Oxide Synthase in Normal and Preeclamptic Placentae
    Khaing A, Swe AT, Aung CL, Thwin MM, Sein MT
    Rev Bras Ginecol Obstet, 2022 Feb;44(2):125-132.
    PMID: 35213910 DOI: 10.1055/s-0042-1742317
    OBJECTIVE:  To investigate the expression of endothelin-1 (ET-1) and endothelial nitric oxide (NO) synthase (eNOS) in normal and preeclamptic (PE) placentae.

    METHODS:  The present cross-sectional analytical study was performed in normal and PE primigravidae (n = 10 in each group) who were admitted to the North Okkalapa General and Teaching Hospital from February 2019 to February 2020. Serum samples were collected immediately before delivery, and placental tissues were collected immediately after emergency or elective cesarean section. The expression of placental eNOS was measured by western blot, and the levels of ET-1 in placental tissue homogenates and in the serum were measured by enzyme-linked immunosorbent assay (ELISA).

    RESULTS:  The PE group had significantly higher serum levels of ET-1 (median: 116.56 pg/mL; IQR: 89.14-159.62 pg/mL) than the normal group (median: 60.02 pg/mL; IQR: 50.89-94.37 pg/mL) (p 

    Matched MeSH terms: Nitric Oxide Synthase Type III
  3. The endothelial nitric oxide synthase gene G894T, glutathione S-transferase (GSTM1 and GSTT1) polymorphisms as a risk factor in the patient with nephrolithiasis
    Mehdi WA, Mehde AA, Yusof F, Raus RA, Resen AK, Ghazali H
    Int J Biol Macromol, 2019 Nov 01;140:719-726.
    PMID: 31445152 DOI: 10.1016/j.ijbiomac.2019.08.184
    BACKGROUND: The genetic features indicate a crucial role in nephrolithiasis. The present study was aimed to investigate the role of Glutathione-S-transferase Mu (GSTM1), Glutathione-S- transferase Theta (GSTT1) and endothelial nitric oxide synthase (eNOs) gene polymorphism in nephrolithiasis.

    METHODS: We involved a case-control study in which 480 individuals were divided into 240 healthy control and 240 patients with nephrolithiasis. For each patient and control, we measured biochemical criteria, levels of glutathione S-transferase, eNOs, GSTM1, GSTT1genes and eNOS genes polymorphism by PCR-RFLP.

    RESULTS: GSTM1 and GSTT1 null genotypes are not a risk features for nephrolithiasis. The eNOS frequency GG, GT, and TT genotypes by using Ban II enzyme as restriction enzyme were found to be (48.33, 36.67, and 15.00) %. The eNOS frequency TT, GT, and GG genotypes by using the Ban II enzyme as restriction enzyme were found to be 15.84, 25.83, and 58.33%, respectively. The result showed an increase in serum eNOs levels were in the patient's group comparing to control.

    CONCLUSIONS: This work is the first in the literature to study the relation between eNOs genes polymorphisms and nephrolithiasis. The results conclude that TT genotypes in the eNOs genes are associated with an increase the oxidative stress in patients.

    Matched MeSH terms: Nitric Oxide Synthase Type III/genetics*
  4. Fulltext Gelam honey scavenges peroxynitrite during the immune response
    Kassim M, Mansor M, Suhaimi A, Ong G, Yusoff KM
    Int J Mol Sci, 2012;13(9):12113-29.
    PMID: 23109904 DOI: 10.3390/ijms130912113
    Monocytes and macrophages are part of the first-line defense against bacterial, fungal, and viral infections during host immune responses; they express high levels of proinflammatory cytokines and cytotoxic molecules, including nitric oxide, reactive oxygen species, and their reaction product peroxynitrite. Peroxynitrite is a short-lived oxidant and a potent inducer of cell death. Honey, in addition to its well-known sweetening properties, is a natural antioxidant that has been used since ancient times in traditional medicine. We examined the ability of Gelam honey, derived from the Gelam tree (Melaleuca spp.), to scavenge peroxynitrite during immune responses mounted in the murine macrophage cell line RAW 264.7 when stimulated with lipopolysaccharide/interferon-γ (LPS/IFN-γ) and in LPS-treated rats. Gelam honey significantly improved the viability of LPS/IFN-γ-treated RAW 264.7 cells and inhibited nitric oxide production-similar to the effects observed with an inhibitor of inducible nitric oxide synthase (1400W). Furthermore, honey, but not 1400W, inhibited peroxynitrite production from the synthetic substrate 3-morpholinosydnonimine (SIN-1) and prevented the peroxynitrite-mediated conversion of dihydrorhodamine 123 to its fluorescent oxidation product rhodamine 123. Honey inhibited peroxynitrite synthesis in LPS-treated rats. Thus, honey may attenuate inflammatory responses that lead to cell damage and death, suggesting its therapeutic uses for several inflammatory disorders.
    Matched MeSH terms: Nitric Oxide Synthase Type II/metabolism
  5. Endothelial nitric oxide synthase G894T gene polymorphism and response to skin reactive hyperemia
    Rasool AH, Ghazali DM, Abdullah H, Halim AS, Wong AR
    Microvasc Res, 2009 Sep;78(2):230-4.
    PMID: 19481100 DOI: 10.1016/j.mvr.2009.05.005
    Post occlusive skin reactive hyperemia (PORH) is a tool used to assess microcirculation. Endothelial nitric oxide synthase (eNOS) mediates nitric oxide (NO) production; polymorphism of the eNOS gene may affect response to the PORH process. This study aims to determine whether eNOS G894T gene polymorphism affects response to skin PORH. 230 normotensive male and females between 18 and 40 years participated in this cross-sectional study. 170 subjects were of the homozygous GG genotype, whereas 60 were of the GT genotype. Skin PORH was performed by occlusion of the upper arm at 200 mm Hg for 3 min. Skin perfusion and temperature were monitored before, during and after occlusion release using the laser Doppler fluximetry. There were no significant differences between genotypes in their baseline blood pressure, serum cholesterol, BMI and age. Maximum change in perfusion after occlusion release (PORHmax) for the GG and GT genotypes were not significantly different at 50.15+/-1.29 vs. 47.92+/-2.17 AU; ANCOVA, p=0.351. Peak perfusion (PORHpeak) were also not significantly different between the two genotypes (61.23+/-1.36 vs. 57.72+/-2.32 AU; p=0.169). Minimum baseline perfusion were however higher in the GG compared to the GT genotype (10.83+/-0.29 vs. 9.61+/-0.50, p=0.029). We conclude that microvascular reactivity, assessed by change in perfusion after temporary ischemia was not significantly different between the GG and GT genotypes of the eNOS G894T gene. eNOS 894T allele carriers however, have lower baseline perfusion compared to the homozygous G894 allele carrier.
    Matched MeSH terms: Nitric Oxide Synthase Type III/genetics*
  6. Candidate gene polymorphisms and their association with hypertension in Malays
    Ghazali DM, Rehman A, Abdul Rahman AR
    Clin Chim Acta, 2008 Feb;388(1-2):46-50.
    PMID: 17977523 DOI: 10.1016/j.cca.2007.10.002
    BACKGROUND: Knowledge of candidate gene polymorphisms in a population is useful for a variety of gene-disease association studies, particularly for some complex traits. A single nucleotide variant of the angiotensinogene gene (AGT M235T) and endothelial nitric oxide synthase gene (eNOS G894T) have been associated with hypertension.
    METHOD: A cross-sectional study consisting of 200 hypertensives and 198 age- and sex-matched controls was conducted. Subjects involved in this study were pure Malay for 3 generations. The AGT M235T and eNOS G894T polymorphisms were determined by PCR-RFLP method.
    RESULTS: The distribution of M235T genotype in the population was 3.5% for MM, 30.4% for MT and 66.1% for TT. No significant difference was observed in genotype (chi(2)=1.30, p=0.52) and allele (chi(2)=0.87, p=0.35) frequencies among the 2 study group. In contrast, the distribution of genotypes for G894T was 74.1% for GG, 24.6% for GT and 1.3% for TT, respectively. Similarly, no significant difference was observed in genotype (chi(2)=0.94, p=0.33) and allele (chi(2)=0.60, p=0.44) frequencies between both study groups.
    CONCLUSION: The AGT M235T and eNOS G894T polymorphisms are unlikely to play an important role in the pathogenesis of hypertension in Malays.
    Study site: Outpatient clinic, Hospital Universiti Sains Malaysia (HUSM); government clinics, Kelantan, Malaysia.
    Matched MeSH terms: Nitric Oxide Synthase Type III/genetics
  7. Fulltext Stimulatory effects of polysaccharide fraction from Solanum nigrum on RAW 264.7 murine macrophage cells
    Razali FN, Ismail A, Abidin NZ, Shuib AS
    PLoS One, 2014;9(10):e108988.
    PMID: 25299340 DOI: 10.1371/journal.pone.0108988
    The polysaccharide fraction from Solanum nigrum Linne has been shown to have antitumor activity by enhancing the CD4+/CD8+ ratio of the T-lymphocyte subpopulation. In this study, we analyzed a polysaccharide extract of S. nigrum to determine its modulating effects on RAW 264.7 murine macrophage cells since macrophages play a key role in inducing both innate and adaptive immune responses. Crude polysaccharide was extracted from the stem of S. nigrum and subjected to ion-exchange chromatography to partially purify the extract. Five polysaccharide fractions were then subjected to a cytotoxicity assay and a nitric oxide production assay. To further analyze the ability of the fractionated polysaccharide extract to activate macrophages, the phagocytosis activity and cytokine production were also measured. The polysaccharide fractions were not cytotoxic, but all of the fractions induced nitric oxide in RAW 264.7 cells. Of the five fractions tested, SN-ppF3 was the least toxic and also induced the greatest amount of nitric oxide, which was comparable to the inducible nitric oxide synthase expression detected in the cell lysate. This fraction also significantly induced phagocytosis activity and stimulated the production of tumor necrosis factor-α and interleukin-6. Our study showed that fraction SN-ppF3 could classically activate macrophages. Macrophage induction may be the manner in which polysaccharides from S. nigrum are able to prevent tumor growth.
    Matched MeSH terms: Nitric Oxide Synthase Type II/metabolism
  8. Fulltext Palm kernel cake extract exerts hepatoprotective activity in heat-induced oxidative stress in chicken hepatocytes
    Oskoueian E, Abdullah N, Idrus Z, Ebrahimi M, Goh YM, Shakeri M, et al.
    BMC Complement Altern Med, 2014;14:368.
    PMID: 25273634 DOI: 10.1186/1472-6882-14-368
    Palm kernel cake (PKC), the most abundant by-product of oil palm industry is believed to contain bioactive compounds with hepatoprotective potential. These compounds may serve as hepatoprotective agents which could help the poultry industry to alleviate adverse effects of heat stress on liver function in chickens.
    Matched MeSH terms: Nitric Oxide Synthase Type II/metabolism
  9. Fulltext Capgermacrenes A and B, Bioactive Secondary Metabolites from a Bornean Soft Coral, Capnella sp
    Phan CS, Ng SY, Kim EA, Jeon YJ, Palaniveloo K, Vairappan CS
    Mar Drugs, 2015 May;13(5):3103-15.
    PMID: 25996100 DOI: 10.3390/md13053103
    Two new bicyclogermacrenes, capgermacrenes A (1) and B (2), were isolated with two known compounds, palustrol (3) and litseagermacrane (4), from a population of Bornean soft coral Capnella sp. The structures of these metabolites were elucidated based on spectroscopic data. Compound 1 was found to inhibit the accumulation of the LPS-induced pro-inflammatory IL-1b and NO production by down-regulating the expression of iNOS protein in RAW 264.7 macrophages.
    Matched MeSH terms: Nitric Oxide Synthase Type II/metabolism
  10. Structural elucidation and anti-asthmatic effects of semi-crystalline polysaccharides from Lignosus rhinocerotis (Cooke) Ryvarden
    Bushra SMR, Safuan S, Abu Bakar R, Lima MA, Abubakar BD, Nurul AA
    Int J Biol Macromol, 2025 Apr;299:140103.
    PMID: 39842582 DOI: 10.1016/j.ijbiomac.2025.140103
    Asthma is a chronic respiratory disease characterized by airway inflammation. Lignosus rhinocerotis (LR), a medicinal mushroom rich in polysaccharide, has been traditionally used to treat various diseases, including asthma. This study aimed to fractionate, characterize and evaluate the anti-asthmatic effects of polysaccharides from LR (LRP). LRP was isolated and characterized using high-performance liquid chromatography (HPLC), x-ray diffraction analysis (XRD), fourier transform infrared spectrometry (FTIR) and nuclear magnetic resonance (NMR) spectroscopy. In an OVA-induced asthma model, BALB/c mice were sensitized, challenged, and intranasally treated with LRP. Experimental findings demonstrated that LRP exhibits a semi-crystalline nature with predicted structure of → 4)-α-D-Glcp-(1 → and → 3)-β-D-Glcp-(1→. LRP significantly reduced eosinophilia, Th2 cytokines, and IgE levels. Histological analysis revealed LRP's ability to decrease epithelial damage and epithelial and smooth muscle thickness in lung. Reductions in inflammatory cell infiltration, mucus production, and transforming growth factor (TGF)-β1 expression were observed, although not statistically significant. Gene expression analysis indicated that LRP significantly downregulated the inducible nitric oxide synthase (iNOS) expression. This study highlights a detailed structural analysis of LRP and its potential as an alternative for the management of asthma. Further research is needed to elucidate the precise mechanisms of action and optimize its therapeutic application.
    Matched MeSH terms: Nitric Oxide Synthase Type II/metabolism
  11. Effects of flavonoids on vascular smooth muscle of the isolated rat thoracic aorta
    Ajay M, Gilani AU, Mustafa MR
    Life Sci, 2003 Dec 19;74(5):603-12.
    PMID: 14623031
    The potency, structure-activity relationship, and mechanism of vasorelaxation of a series of flavonoids, representing different subclasses (flavonols: fisetin, rutin, quercetin; flavones: chrysin, flavone, baicalein; flavanones: naringenin, naringin; isoflavones: diadzein and flavanes: epigallo catechin gallate), were examined in the isolated rat aorta. Most of the flavonoids tested showed concentration dependent relaxant effects against K+ (80 mM) and phenylephrine (PE, 0.1 microM)-induced contractions with a greater inhibition of the responses to the alpha1-adrenoceptor agonist. The relaxant effects of most of the flavonoids involve in part the release of nitric oxide and prostaglandins from the endothelium as pretreatment with L-NAME and indomethacin attenuated the responses. In addition, the relaxant action of the flavonoids includes inhibition of Ca+2 influx and release of Ca+2 from intracellular stores. A structure-activity relationship amongst the flavonoids was suggested.
    Matched MeSH terms: Nitric Oxide Synthase/antagonists & inhibitors; Nitric Oxide Synthase Type III
  12. Nitric oxide production by a human osteoblast cell line stimulated with Aggregatibacter actinomycetemcomitans lipopolysaccharide
    Sosroseno W, Bird PS, Seymour GJ
    Oral Microbiol. Immunol., 2009 Feb;24(1):50-5.
    PMID: 19121070 DOI: 10.1111/j.1399-302X.2008.00475.x
    Human osteoblasts induced by inflammatory stimuli express an inducible nitric oxide synthase (iNOS). The aim of the present study was to test the hypothesis that Aggregatibacter actinomycetemcomitans lipopolysaccharide stimulates the production of nitric oxide (NO) by a human osteoblast-like cell line (HOS cells).
    Matched MeSH terms: Nitric Oxide Synthase Type II/antagonists & inhibitors; Nitric Oxide Synthase Type II/metabolism*
  13. A synthetic curcuminoid derivative inhibits nitric oxide and proinflammatory cytokine synthesis
    Tham CL, Liew CY, Lam KW, Mohamad AS, Kim MK, Cheah YK, et al.
    Eur J Pharmacol, 2010 Feb 25;628(1-3):247-54.
    PMID: 19958764 DOI: 10.1016/j.ejphar.2009.11.053
    Curcumin is a highly pleiotropic molecule with significant regulatory effects upon inflammation and inflammatory related diseases. However curcumin has one major important limitation in which it has poor bioavailability. Design of synthetic structural derivatives of curcumin is but one approach that has been used to overcome its poor bioavailability while retaining, or further enhancing, its drug-like effects. We have synthesized a series of curcumin analogues and describe the effects of 2,6-bis-4-(hydroxyl-3-methoxy-benzylidine)-cyclohexanone or BHMC upon nitric oxide and cytokine synthesis in cellular models of inflammation. BHMC showed a significant dose-response inhibitory action upon the synthesis of NO and we have shown that this effect was due to suppression of both iNOS gene and enzyme expression without any effects upon scavenging of nitrite. We also demonstrated that BHMC has a very minimal effect upon iNOS activity with no effect at all upon the secretion of PGE(2) but has a strong inhibitory effect upon MCP-1 and IL-10 secretion and gene expression. Secretion and gene expression of TNF-alpha and IL-6 were moderately inhibited whereas IL-8 and IL-1beta were not altered. We conclude that BHMC selectively inhibits the synthesis of several inflammatory mediators. BHMC should be considered a promising drug lead for preclinical and further pharmacological studies.
    Matched MeSH terms: Nitric Oxide Synthase Type II/genetics; Nitric Oxide Synthase Type II/metabolism
  14. The antinociceptive activity of Muntingia calabura aqueous extract and the involvement of L-arginine/nitric oxide/cyclic guanosine monophosphate pathway in its observed activity in mice
    Zakaria ZA, Sulaiman MR, Jais AM, Somchit MN, Jayaraman KV, Balakhrisnan G, et al.
    Fundam Clin Pharmacol, 2006 Aug;20(4):365-72.
    PMID: 16867020
    The present study was carried out to investigate on the possible involvement of L-arginine/nitric oxide/cyclic guanosine monophosphate (L-arginine/NO/cGMP) pathway in the aqueous extract of Muntingia calabura (AEMC) leaves antinociception in mice assessed by abdominal constriction test. The AEMC, obtained by soaking the dried leaves in distilled water (DH(2)O) (1 : 2; w/v) for 24 h, was prepared in concentrations of 10%, 50% and 100% that were approximately equivalent to doses of 27, 135 and 270 mg/kg, and administered subcutaneously (s.c.) 5 min after pre-treatment (s.c.) of mice with DH(2)O, L-arginine (20 mg/kg), N(G)-monomethyl-L-arginine acetate (L-NMMA; 20 mg/kg), N(G)-nitro-L-arginine methyl esters (L-NAME; 20 mg/kg), methylene blue (MB) (20 mg/kg), respectively. The AEMC was found to exhibit a concentration-dependent antinociception after pre-challenge with DH(2)O. Interestingly, pre-treatment with L-arginine was found to block significantly (P < 0.05) the AEMC antinociception but only at the highest concentration (100%) of AEMC used. On the other hand, pre-treatment with L-NAME was found to significantly (P < 0.05) enhance the low concentration but inhibit the high concentration AEMC antinociception. MB was found to significantly (P < 0.05) enhance AEMC antinociception at all concentrations used. Except for the higher concentration of AEMC used, co-treatment with L-NAME was found to insignificantly and significantly (P < 0.05) reverse the L-arginine effect when given alone or with low concentration AEMC, respectively. In addition, co-treatment with MB significantly (P < 0.05) reversed the L-arginine effect when given alone or with 10% concentration AEMC but failed to affect the activity of the rest of concentrations used. As a conclusion, this study has demonstrated the involvement of L-arginine/NO/cGMP pathway in AEMC antinociception.
    Matched MeSH terms: Nitric Oxide Synthase/antagonists & inhibitors; Nitric Oxide Synthase/metabolism
  15. Effects of acute ammonia toxicity on nitric oxide (NO), citrulline-NO cycle enzymes, arginase and related metabolites in different regions of rat brain
    Swamy M, Zakaria AZ, Govindasamy C, Sirajudeen KN, Nadiger HA
    Neurosci Res, 2005 Oct;53(2):116-22.
    PMID: 16009439
    Nitric oxide (NO) is involved in many pathophysiological processes in the brain. NO is synthesized from arginine by nitric oxide synthase (NOS) enzymes. Citrulline formed as a by-product of the NOS reaction, can be recycled to arginine by successive actions of argininosuccinate synthetase (ASS) and argininosuccinate lyase (ASL) via the citrulline-NO cycle. Hyperammonemia is known to cause poorly understood perturbations of the citrulline-NO cycle. To understand the role of citrulline-NO cycle in hyperammonemia, NOS, ASS, ASL and arginase activities, as well as nitrate/nitrite (NOx), arginine, ornithine, citrulline, glutamine, glutamate and GABA were estimated in cerebral cortex (CC), cerebellum (CB) and brain stem (BS) of rats subjected to acute ammonia toxicity. NOx concentration and NOS activity were found to increase in all the regions of brain in acute ammonia toxicity. The activities of ASS and ASL showed an increasing trend whereas the arginase was not changed. The results of this study clearly demonstrated the increased formation of NO, suggesting the involvement of NO in the pathophysiology of acute ammonia toxicity. The increased activities of ASS and ASL suggest the increased and effective recycling of citrulline to arginine in acute ammonia toxicity, making NO production more effective and contributing to its toxic effects.
    Matched MeSH terms: Nitric Oxide Synthase/drug effects; Nitric Oxide Synthase/metabolism
  16. Effects of 3-(2-Hydroxyphenyl)-1-(5-methyl-furan-2-y-l) propenone (HMP) upon signalling pathways of lipopolysaccharide-induced iNOS synthesis in RAW 264.7 cells
    Liew CY, Lam KW, Kim MK, Harith HH, Tham CL, Cheah YK, et al.
    Int Immunopharmacol, 2011 Jan;11(1):85-95.
    PMID: 21035434 DOI: 10.1016/j.intimp.2010.10.011
    We previously showed that 3-(2-hydroxyphenyl)-1-(5-methyl-furan-2-y-l)propenone (HMP), suppressed the synthesis of various proinflammatory mediators. In this study, HMP showed a dose-dependent inhibition of NO synthesis in the RAW 264.7 murine macrophage line. The inhibition of NO synthesis was related to inhibition of p38 phosphorylation and kinase activity that led to significant inhibition of phosphorylation of ATF-2. This effect in turn caused inhibition of AP-1-DNA binding which partially explains the inhibitory effect upon the synthesis of iNOS. HMP had no effect upon phosphorylation of JNK, ERK1/2 and STAT-1. Kinase activity of JNK and ERK1/2 was also not affected by HMP as determined by levels of phosphorylated c-jun and phosphorylated elk-1. Furthermore HMP failed to block phosphorylation of IκBα, and subsequent nuclear translocation and DNA-binding activity of p65 NF-κB in IFN-γ/LPS-induced RAW 264.7 cells. Molecular docking experiments confirmed that HMP fits well in the highly conserved hydrophobic pocket of p38 MAP kinase. We conclude that the synthetic HMP is a chalcone analogue that selectively inhibits the p38/ATF-2 and AP-1 signaling pathways in the NO synthesis by the macrophage RAW 264.7.
    Matched MeSH terms: Nitric Oxide Synthase Type II/antagonists & inhibitors*; Nitric Oxide Synthase Type II/biosynthesis
  17. Fulltext Paclitaxel Inhibits Expression of Neuronal Nitric Oxide Synthase and Prevents Mitochondrial Dysfunction in Spinal Ventral Horn in Rats After C7 Spinal Root Avulsion
    Sim SK, Tan YC, Tee JH, Yusoff AA, Abdullah JM
    Turk Neurosurg, 2015;25(4):617-24.
    PMID: 26242340 DOI: 10.5137/1019-5149.JTN.14035-15.1
    This study evaluated the neuroprotective effect of intrathecally infused paclitaxel in the prevention of motoneuron death and mitochondrial dysfunction following brachial plexus avulsion injury.
    Matched MeSH terms: Nitric Oxide Synthase Type I/antagonists & inhibitors*; Nitric Oxide Synthase Type I/biosynthesis*
  18. Fulltext Pulsatile stretch as a novel modulator of amyloid precursor protein processing and associated inflammatory markers in human cerebral endothelial cells
    Gangoda SVS, Avadhanam B, Jufri NF, Sohn EH, Butlin M, Gupta V, et al.
    Sci Rep, 2018 01 26;8(1):1689.
    PMID: 29374229 DOI: 10.1038/s41598-018-20117-6
    Amyloid β (Aβ) deposition is a hallmark of Alzheimer's disease (AD). Vascular modifications, including altered brain endothelial cell function and structural viability of the blood-brain barrier due to vascular pulsatility, are implicated in AD pathology. Pulsatility of phenomena in the cerebral vasculature are often not considered in in vitro models of the blood-brain barrier. We demonstrate, for the first time, that pulsatile stretch of brain vascular endothelial cells modulates amyloid precursor protein (APP) expression and the APP processing enzyme, β-secretase 1, eventuating increased-Aβ generation and secretion. Concurrent modulation of intercellular adhesion molecule 1 and endothelial nitric oxide synthase (eNOS) signaling (expression and phosphorylation of eNOS) in response to pulsatile stretch indicates parallel activation of endothelial inflammatory pathways. These findings mechanistically support vascular pulsatility contributing towards cerebral Aβ levels.
    Matched MeSH terms: Nitric Oxide Synthase Type III/analysis
  19. Fulltext 3',4'-dihydroxyflavonol ameliorates endoplasmic reticulum stress-induced apoptosis and endothelial dysfunction in mice
    Lau YS, Mustafa MR, Choy KW, Chan SMH, Potocnik S, Herbert TP, et al.
    Sci Rep, 2018 01 29;8(1):1818.
    PMID: 29379034 DOI: 10.1038/s41598-018-19584-8
    Endoplasmic reticulum (ER) stress has been implicated in the development of hypertension 3 through the induction of endothelial impairment. As 3',4'-dihydroxyflavonol (DiOHF) 4 reduces vascular injury caused by ischaemia/reperfusion or diabetes, and flavonols have been demonstrated to attenuate ER stress, we investigated whether DiOHF can protect mice from ER stress-induced endothelial dysfunction. Male C57BLK/6 J mice were injected with tunicamycin to induce ER stress in the presence or absence of either DiOHF or tauroursodeoxycholic acid (TUDCA), an inhibitor of ER stress. Tunicamycin elevated blood pressure and impaired endothelium-dependent relaxation. Moreover, in aortae there was evidence of ER stress, oxidative stress and reduced NO production. This was coincident with increased NOX2 expression and reduced phosphorylation of endothelial nitric oxide synthase (eNOS) on Ser1176. Importantly, the effects of tunicamycin were significantly ameliorated by DiOHF or TUDCA. DiOHF also inhibited tunicamycin-induced ER stress and apoptosis in cultured human endothelial cells (HUVEC). These results provide evidence that ER stress is likely an important initiator of endothelial dysfunction through the induction of oxidative stress and a reduction in NO synthesis and that DiOHF directly protects against ER stress- induced injury. DiOHF may be useful to prevent ER and oxidative stress to preserve endothelial function, for example in hypertension.
    Matched MeSH terms: Nitric Oxide Synthase Type III/metabolism
  20. A Cyclic Peptide Inhibitor of the iNOS-SPSB Protein-Protein Interaction as a Potential Anti-Infective Agent
    Sadek MM, Barlow N, Leung EWW, Williams-Noonan BJ, Yap BK, Shariff FM, et al.
    ACS Chem Biol, 2018 10 19;13(10):2930-2938.
    PMID: 30226743 DOI: 10.1021/acschembio.8b00561
    SPRY domain- and SOCS box-containing proteins SPSB1, SPSB2, and SPSB4 interact with inducible nitric oxide synthase (iNOS), causing the iNOS to be polyubiquitinated and targeted for degradation. Inhibition of this interaction increases iNOS levels, and consequently cellular nitric oxide (NO) concentrations, and has been proposed as a potential strategy for killing intracellular pathogens. We previously described two DINNN-containing cyclic peptides (CP1 and CP2) as potent inhibitors of the murine SPSB-iNOS interaction. In this study, we report the crystal structures of human SPSB4 bound to CP1 and CP2 and human SPSB2 bound to CP2. We then used these structures to design a new inhibitor in which an intramolecular hydrogen bond was replaced with a hydrocarbon linkage to form a smaller macrocycle while maintaining the bound geometry of CP2 observed in the crystal structures. This resulting pentapeptide SPSB-iNOS inhibitor (CP3) has a reduced macrocycle ring size, fewer nonbinding residues, and includes additional conformational constraints. CP3 has a greater affinity for SBSB2 ( KD = 7 nM as determined by surface plasmon resonance) and strongly inhibits the SPSB2-iNOS interaction in macrophage cell lysates. We have also determined the crystal structure of CP3 in complex with human SPSB2, which reveals the structural basis for the increased potency of CP3 and validates the original design.
    Matched MeSH terms: Nitric Oxide Synthase Type II/metabolism*
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