Sample records for lps-induced inducible nitric

  1. Structural requirements of sesquiterpene lactones to inhibit LPS-induced nitric oxide synthesis in RAW 264.7 macrophages

    Microsoft Academic Search

    Verena M Dirsch; Hermann Stuppner; Ernst P Ellmerer-Müller; Angelika M Vollmar

    2000-01-01

    Some sesquiterpene lactones were recently demonstrated to inhibit inducible nitric oxide synthase (iNOS)-dependent nitric oxide (NO) synthesis. The primary objective of the present study was, therefore, to find evidence for structural requirements of sesquiterpene lactones regarding their capability to inhibit iNOS-dependent NO synthesis. Sesquiterpene lactones 1–11 were examined for their influence on nitrite accumulation in cell culture supernatants of LPS-induced

  2. Nitric oxide synthase inhibitors exert differential time-dependent effects on LPS-induced uveitis.

    PubMed

    Allen, J B; McGahan, M C; Ferrell, J B; Adler, K B; Fleisher, L N

    1996-01-01

    Nitric oxide (NO) is a highly reactive radical which plays an integral role in physiological and pathophysiological processes. NO is produced endogenously in small amounts by a constitutive NO synthase (cNOS) as a regulator of vascular tone and neurotransmission. NO can also be produced in large amounts by an inducible NOS (iNOS) in response to endotoxin and cytokines, and has been reported to be a mediator of lipopolysaccharide (LPS)-induced uveitis in rats. The purpose of the present study was to investigate the effects of NOS inhibitors with different NOS isoform specificities in the rabbit model of endotoxin-induced ocular inflammation. LPS and/or inhibitors of NOS. NG-nitro-L-arginine methyl ester (L-NAME) and aminoguanidine (AG), were injected intravitreally and the eyes observed by slit lamp for 24 hr. Coinjection of LPS with L-NAME inhibited anterior inflammation in rabbits. Iridal hyperemia (IH) and aqueous flare (AF) were completely abolished in eight out of nine rabbits in a dose-dependent manner. In addition, total cell counts were significantly suppressed (7393 +/- 697 vs. 325 +/- 188, P < 0.05) and aqueous protein levels were reduced to near control levels (25 +/- 0.75 vs. 1.72 +/- 0.36, P < 0.05). Similar suppression was seen with AG (cell counts = 351 +/- 246 and proteins = 3.1 +/- 1.2). Administration of L-NAME 0.5 hr after LPS injection suppressed inflammation to a lesser extent than coinjection. In contrast, administration of L-NAME 6 hr after LPS injection was not inhibitory, and in fact significantly increased cellular infiltration. However, AG given 6 hr after LPS had a remarkably different effect, since it significantly decreased both protein extravasation and cellular infiltration into the aqueous humor. In fact, our results suggest that cNOS may play a greater role in the earlier stages of this developing inflammatory response. These results extend others' observations that NO is a key mediator in uveitis, that induction of iNOS plays a critical role in experimental uveitis, and suggest that NO has a complex role in the ocular inflammatory process. Inhibitors of NOS can abort the LPS-induced inflammatory response if administered early enough, but could potentially exacerbate an established inflammatory episode. PMID:8674509

  3. Inhibition of LPS-induced nitric oxide production in RAW cells by radioprotective thiols.

    PubMed

    Kumar, K Sree; Singh, Vijay K; Jackson, William; Seed, Thomas M

    2003-02-01

    Nitric oxide (NO) is involved in producing damage after exposure to radiation and also in the toxicity associated with bacterial endotoxin (lipopolysaccharide, LPS). We have evaluated different radioprotective thiols for their effects on LPS-stimulated NO production in mouse macrophage cells, RAW 264.7. Our results indicate that although thiols inhibited NO production in general, the degree of inhibition depended upon the thiol compound. Long-chain aminothiols like WR-1065 [N-(2-mercaptoethyl)-1,3-diaminopropane] exerted a strong inhibition; but its parent drug, amifostine, which protects mice against radiation lethality, was not as effective as WR-1065. Diethyl dithiocarbamate, which is less effective than amifostine as a radioprotector, strongly inhibited NO production from macrophages. These results indicate that the radioprotective potential of sulfhydryl compounds is not related to its ability to inhibit NO production by macrophages and suggest that some of the thiol radioprotectors may effectively ameliorate the fatal symptoms of hypotensive shock, associated with endotoxin (LPS)-induced NO production. PMID:12645634

  4. LPS induces inflammatory responses in human aortic vascular smooth muscle cells via Toll-like receptor 4 expression and nitric oxide production

    Microsoft Academic Search

    Sook-Kyoung Heo; Hyun-Jeong Yun; Eui-Kyu Noh; Won-Hwan Park; Sun-Dong Park

    2008-01-01

    Inflammation is an important event in the development of vascular diseases such as hypertension, atherosclerosis, and restenosis. In addition, the stimulation of Toll-like receptor 4 (TLR4) by lipopolysaccharide (LPS) induces the release of critical proinflammatory cytokines that activate potent immune responses. In this study, LPS was found to induce TLR4 expression and increased nitric oxide (NO) production by increasing the

  5. Chemical constituents isolated from the Mongolian medicinal plant Sophora alopecuroides L. and their inhibitory effects on LPS-induced nitric oxide production in RAW 264.7 macrophages.

    PubMed

    Kwon, Jaeyoung; Basnet, Sunita; Lee, Jin Woo; Seo, Eun-Kyoung; Tsevegsuren, Nanzad; Hwang, Bang Yeon; Lee, Dongho

    2015-08-15

    Three new flavonostilbenes, alopecurones M-O (1-3), were isolated from the root bark of Sophora alopecuroides L. together with 21 known compounds. The structures of the isolated compounds were elucidated by using NMR, MS, and CD spectroscopic data. All isolates were evaluated for their potential to inhibit LPS-induced nitric oxide production in RAW 264.7 cells. PMID:26073007

  6. Inducible nitric oxide synthase is key to peroxynitrite-mediated, LPS-induced protein radical formation in murine microglial BV2 cells.

    PubMed

    Kumar, Ashutosh; Chen, Shih-Heng; Kadiiska, Maria B; Hong, Jau-Shyong; Zielonka, Jacek; Kalyanaraman, Balaraman; Mason, Ronald P

    2014-08-01

    Microglia are the resident immune cells in the brain. Microglial activation is characteristic of several inflammatory and neurodegenerative diseases including Alzheimer's disease, multiple sclerosis, and Parkinson's disease. Though lipopolysaccharide (LPS)-induced microglial activation in models of Parkinson's disease is well documented, the free radical-mediated protein radical formation and its underlying mechanism during LPS-induced microglial activation are not known. Here we have used immuno-spin trapping and RNA interference to investigate the role of inducible nitric oxide synthase (iNOS) in peroxynitrite-mediated protein radical formation in murine microglial BV2 cells treated with LPS. Treatment of BV2 cells with LPS resulted in morphological changes, induction of iNOS, and increased protein radical formation. Pretreatments with FeTPPS (a peroxynitrite decomposition catalyst), L-NAME (total NOS inhibitor), 1400W (iNOS inhibitor), and apocynin significantly attenuated LPS-induced protein radical formation and tyrosine nitration. Results obtained with coumarin-7-boronic acid, a highly specific probe for peroxynitrite detection, correlated with LPS-induced tyrosine nitration, which demonstrated involvement of peroxynitrite in protein radical formation. A similar degree of protection conferred by 1400W and L-NAME led us to conclude that only iNOS, and no other forms of NOS, is involved in LPS-induced peroxynitrite formation. Subsequently, siRNA for iNOS, the iNOS-specific inhibitor 1400W, the NF-?B inhibitor PDTC, and the p38 MAPK inhibitor SB202190 was used to inhibit iNOS directly or indirectly. Inhibition of iNOS precisely correlated with decreased protein radical formation in LPS-treated BV2 cells. The time course of protein radical formation also matched the time course of iNOS expression. Taken together, these results prove the role of iNOS in peroxynitrite-mediated protein radical formation in LPS-treated microglial BV2 cells. PMID:24746617

  7. Nitric oxide suppresses LPS-induced inflammation in a mouse asthma model by attenuating the interaction of IKK and Hsp90.

    PubMed

    Lee, Ming-Yung; Sun, Kuang-Hui; Chiang, Chien-Ping; Huang, Ching-Feng; Sun, Guang-Huan; Tsou, Yu-Chi; Liu, Huan-Yun; Tang, Shye-Jye

    2015-04-01

    A feature of allergic airway disease is the observed increase of nitric oxide (NO) in exhaled breath. Gram-negative bacterial infections have also been linked with asthma exacerbations. However, the role of NO in asthma exacerbations with gram-negative bacterial infections is still unclear. In this study, we examined the role of NO in lipopolysaccharide (LPS)-induced inflammation in an ovalbumin (OVA)-challenged mouse asthma model. To determine whether NO affected the LPS-induced response, a NO donor (S-nitroso-N-acetylpenicillamine, SNAP) or a selective inhibitor of NO synthase (1400W) was injected intraperitoneally into the mice before the LPS stimulation. Decreased levels of proinflammatory cytokines were demonstrated in the bronchoalveolar lavage fluid from mice treated with SNAP, whereas increased levels of cytokines were found in the 1400W-treated mice. To further explore the molecular mechanism of NO-mediated inhibition of proinflammatory responses in macrophages, RAW 264.7 cells were treated with 1400W or SNAP before LPS stimulation. LPS-induced inflammation in the cells was attenuated by the presence of NO. The LPS-induced I?B kinase (IKK) activation and the expression of IKK were reduced by NO through attenuation of the interaction between Hsp90 and IKK in the cells. The IKK decrease in the lung immunohistopathology was verified in SNAP-treated asthma mice, whereas IKK increased in the 1400W-treated group. We report for the first time that NO attenuates the interaction between Hsp90 and IKK, decreasing the stability of IKK and causing the down-regulation of the proinflammatory response. Furthermore, the results suggest that NO may repress LPS-stimulated innate immunity to promote pulmonary bacterial infection in asthma patients. PMID:25519430

  8. Oxidized cholesterol in oxidized low density lipoprotein may be responsible for the inhibition of LPS-induced nitric oxide production in macrophages 1 The project was supported by National Natural Science Foundation of China. 1

    Microsoft Academic Search

    Shang-Xi Liu; Yuan Chen; Mei Zhou; Jennifer Wan

    1998-01-01

    Previous work has shown that oxidized low density lipoprotein (Ox-LDL) inhibited lipopolysacchride (LPS)-induced nitric oxide (NO) production in macrophages. In this paper, the role of different components of Ox-LDL in the inhibitory effect was studied by measuring nitrite in media. Ox-LDL inhibited LPS-induced NO production in macrophage cell line J774.A1. When compared with Ox-LDL, native and acetylated LDL had a

  9. Hypericum triquetrifolium-Derived Factors Downregulate the Production Levels of LPS-Induced Nitric Oxide and Tumor Necrosis Factor-? in THP-1 Cells.

    PubMed

    Saad, Bashar; Abouatta, Bernadette Soudah; Basha, Walid; Hmade, Alaa; Kmail, Abdalsalam; Khasib, Said; Said, Omar

    2011-01-01

    Based on knowledge from traditional Arab herbal medicine, this in vitro study aims to examine the anti-inflammatory mechanism of Hypericum triquetrifolium by measuring the expression and release of pro-inflammatory cytokines, tumor necrosis factor-? (TNF-?) and interleukine-6 (IL-6), and inducible nitric oxide synthase (iNOS) in human monocytic cells, THP-1. The effects were assessed by measuring the levels of secretory proteins and mRNA of TNF-? and IL-6, the levels of nitric oxide (NO) secretion and the expression of iNOS in THP-1 cells. Cells were treated with 5??g lipopolysaccharide/ml (LPS) in the presence and absence of increasing concentrations of extracts from the aerial parts of H. triquetrifolium. During the entire experimental period, we used extract concentrations (up to 250??g?mL(-1)) that had no cytotoxic effects, as measured with MTT and LDH assays. Hypericum triquetrifolium extracts remarkably suppressed the LPS-induced NO release, significantly attenuated the LPS-induced transcription of iNOS and inhibited in a dose-dependent manner the expression and release of TNF-?. No significant effects were observed on the release of IL-6. Taken together, these results suggest that H. triquetrifolium probably exerts anti-inflammatory effects through the suppression of TNF-? and iNOS expressions. PMID:18955363

  10. Nitric oxide post-transcriptionally up-regulates LPS-induced IL8 expression through p38 MAPK activation

    Microsoft Academic Search

    Penglin Ma; Xiaolin Cui; Shuibang Wang; Jianhua Zhang; Ervant V. Nishanian; Weihan Wang; Robert A. Wesley; Robert L. Danner

    2004-01-01

    Nitric oxide (NO) contributes to vascu- lar collapse in septic shock and regulates inflam- mation. Here, we demonstrate in lipopolysaccha- ride (LPS)-stimulated human THP-1 cells and monocytes that NO regulates interleukin (IL)-8 and tumor necrosis factor (TNF-) by distinct mechanisms. Dibutyryl-cyclic guanosine 5-mono- phosphate (cGMP) failed to simulate NO-induced increases in TNF- or IL-8 production. In con- trast, dibutyryl-cyclic adenosine

  11. ?-Phenylethyl and 8-methylsulphinyloctyl isothiocyanates, constituents of watercress, suppress LPS induced production of nitric oxide and prostaglandin E2 in RAW 264.7 macrophages

    Microsoft Academic Search

    Peter Rose; Yen Kim Won; Choon Nam Ong; Matt Whiteman

    2005-01-01

    ?-Phenylethyl (PEITC) and 8-methylsulphinyloctyl isothiocyanates (MSO) represent two phytochemical constituents present in watercress Rorripa nasturtium aquaticum, with known chemopreventative properties. In the present investigation, we examined whether PEITC and MSO could modulate the inflammatory response of Raw 264.7 macrophages to bacterial lipopolysaccharide (LPS) by assessment of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression. Overproduction of both nitric oxide

  12. Silibinin ameliorates LPS-induced memory deficits in experimental animals.

    PubMed

    Joshi, Ritu; Garabadu, Debapriya; Teja, Gangineni Ravi; Krishnamurthy, Sairam

    2014-12-01

    Neuroinflammation is considered as one of the predisposing factor in the etiology of several neurodegenerative disorders. Therefore, the objective of the present study was to evaluate the protective effect of silibinin (SIL) in the lipopolysaccharide (LPS)-induced neuroinflammatory model. The effect of SIL on memory function was also evaluated on normal rats without LPS administration. In the first experiment, male rats were divided into five groups. Except control group animals, all rats received bilateral intracerebroventricular injection of LPS (5 ?g/5 ?l) into lateral ventricles on the first day of the experimental schedule. Control rats received bilateral intracerebroventricular injection of artificial cerebrospinal fluid into lateral ventricles. SIL in doses of 50, 100 and 200 mg/kg, p.o. was administered 1h before LPS injection and continued for 7 days. On Day-7, SIL attenuated the LPS-induced long-term and working memory loss in elevated plus and Y-maze test respectively. Further, SIL dose-dependently attenuated LPS-induced decrease in acetylcholine level and increase in the acetylcholinestrase activity in hippocampus and pre-frontal cortex. SIL ameliorated LPS-induced decrease in the mitochondrial complex activity (I, IV and V) and integrity, increase in lipid peroxidation and decrease in the activity of superoxide dismutase in both the brain regions. SIL attenuated amyloidogenesis in the hippocampus, while it decreased the LPS-induced increase in the level of NF?B in the pre-frontal cortex. In another study, SIL dose-dependently, enhanced memory functions in the normal rats, indicating its nootropic activity. Hence, SIL could be a potential candidate in the management of neuroinflammation-related memory disorders. PMID:25444719

  13. Hypericum triquetrifolium—Derived Factors Downregulate the Production Levels of LPS-Induced Nitric Oxide and Tumor Necrosis Factor-a in THP1 Cells

    Microsoft Academic Search

    Bashar Saad; Bernadette Soudah AbouAtta; Walid Basha; Alaa Hmade; Abdalsalam Kmail; Said Khasib; Shefa Amr

    2008-01-01

    Based on knowledge from traditional Arab herbal medicine, this in vitro study aims to examine the anti-inflammatory mechanism of Hypericum triquetrifolium by measuring the expression and release of pro-inflammatory cytokines, tumor necrosis factor-a (TNF-a) and interleukine-6 (IL-6), and inducible nitric oxide synthase (iNOS) in human monocytic cells, THP-1. The effects were assessed by measuring the levels of secretory proteins and

  14. Achillea millefolium L. Essential Oil Inhibits LPS-Induced Oxidative Stress and Nitric Oxide Production in RAW 264.7 Macrophages.

    PubMed

    Chou, Su-Tze; Peng, Hsin-Yi; Hsu, Jaw-Cherng; Lin, Chih-Chien; Shih, Ying

    2013-01-01

    Achillea millefolium L. is a member of the Asteraceae family and has been used in folk medicine in many countries. In this study, 19 compounds in A. millefolium essential oil (AM-EO) have been identified; the major components are artemisia ketone (14.92%), camphor (11.64%), linalyl acetate (11.51%) and 1,8-cineole (10.15%). AM-EO can suppress the inflammatory responses of lipopolysaccharides (LPS)-stimulated RAW 264.7 macrophages, including decreased levels of cellular nitric oxide (NO) and superoxide anion production, lipid peroxidation and glutathione (GSH) concentration. This antioxidant activity is not a result of increased superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities, but rather occurs as a result of the down-regulation of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-? (TNF-?), interleukin-6 (IL-6) and heme oxygenase-1 (HO-1) expression, thus reducing the inflammatory response. Therefore, AM-EO can be utilized in many applications, including the treatment of inflammatory diseases in the future. PMID:23797659

  15. Inhibition of IRAK-4 activity for rescuing endotoxin LPS-induced septic mortality in mice by lonicerae flos extract

    SciTech Connect

    Park, Sun Hong; Roh, Eunmiri [College of Pharmacy, Chungbuk National University, Cheongju 361-763 (Korea, Republic of)] [College of Pharmacy, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Kim, Hyun Soo [Pharmaceutical R and D Center, Huons Co., Ltd., Anyang (Korea, Republic of)] [Pharmaceutical R and D Center, Huons Co., Ltd., Anyang (Korea, Republic of); Baek, Seung-Il [College of Pharmacy, Chungbuk National University, Cheongju 361-763 (Korea, Republic of)] [College of Pharmacy, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Choi, Nam Song [Pharmaceutical R and D Center, Huons Co., Ltd., Anyang (Korea, Republic of)] [Pharmaceutical R and D Center, Huons Co., Ltd., Anyang (Korea, Republic of); Kim, Narae; Hwang, Bang Yeon; Han, Sang-Bae [College of Pharmacy, Chungbuk National University, Cheongju 361-763 (Korea, Republic of)] [College of Pharmacy, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Kim, Youngsoo, E-mail: youngsoo@chungbuk.ac.kr [College of Pharmacy, Chungbuk National University, Cheongju 361-763 (Korea, Republic of)] [College of Pharmacy, Chungbuk National University, Cheongju 361-763 (Korea, Republic of)

    2013-12-13

    Highlights: •Lonicerae flos extract (HS-23) is a clinical candidate, Phase I for sepsis treatment. •Here, HS-23 or its major constituents rescued LPS-induced septic mortality in mice. •As a mechanism, they directly inhibited IRAK-4-catalyzed kinase activity. •Thus, they suppressed LPS-induced expression of NF-?B/AP-1-target inflammatory genes. -- Abstract: Lonicerae flos extract (HS-23) is a clinical candidate currently undergoing Phase I trial in lipopolysaccharide (LPS)-injected healthy human volunteers, but its molecular basis remains to be defined. Here, we investigated protective effects of HS-23 or its major constituents on Escherichia coli LPS-induced septic mortality in mice. Intravenous treatment with HS-23 rescued LPS-intoxicated C57BL/6J mice under septic conditions, and decreased the levels of cytokines such as tumor necrosis factor ? (TNF-?), interleukin (IL)-1? and high-mobility group box-1 (HMGB-1) in the blood. Chlorogenic acid (CGA) and its isomers were assigned as major constituents of HS-23 in the protection against endotoxemia. As a molecular mechanism, HS-23 or CGA isomers inhibited endotoxin LPS-induced autophosphorylation of the IL-1 receptor-associated kinase 4 (IRAK-4) in mouse peritoneal macrophages as well as the kinase activity of IRAK-4 in cell-free reactions. HS-23 consequently suppressed downstream pathways critical for LPS-induced activation of nuclear factor (NF)-?B or activating protein 1 (AP-1) in the peritoneal macrophages. HS-23 also inhibited various toll-like receptor agonists-induced nitric oxide (NO) production, and down-regulated LPS-induced expression of NF-?B/AP-1-target inflammatory genes in the cells. Taken together, HS-23 or CGA isomers exhibited anti-inflammatory therapy against LPS-induced septic mortality in mice, at least in part, mediated through the inhibition of IRAK-4.

  16. The protective effect of melatonin on neural stem cell against LPS-induced inflammation.

    PubMed

    Song, Juhyun; Kang, So Mang; Lee, Kyoung Min; Lee, Jong Eun

    2015-01-01

    Stem cell therapy for tissue regeneration has several limitations in the fact that transplanted cells could not survive for a long time. For solving these limitations, many studies have focused on the antioxidants to increase survival rate of neural stem cells (NSCs). Melatonin, an antioxidant synthesized in the pineal gland, plays multiple roles in various physiological mechanisms. Melatonin exerts neuroprotective effects in the central nervous system. To determine the effect of melatonin on NSCs which is in LPS-induced inflammatory stress state, we first investigated nitric oxide (NO) production and cytotoxicity using Griess reagent assays, LDH assay, and neurosphere counting. Also, we investigated the effect of melatonin on NSCs by measuring the mRNA levels of SOX2, TLX, and FGFR-2. In addition, western blot analyses were performed to examine the activation of PI3K/Akt/Nrf2 signaling in LPS-treated NSCs. In the present study, we suggested that melatonin inhibits NO production and protects NSCs against LPS-induced inflammatory stress. In addition, melatonin promoted the expression of SOX2 and activated the PI3K/Akt/Nrf2 signaling under LPS-induced inflammation condition. Based on our results, we conclude that melatonin may be an important factor for the survival and proliferation of NSCs in neuroinflammatory diseases. PMID:25705693

  17. LPS induces translocation of TLR4 in amniotic epithelium.

    PubMed

    Adams, K M; Lucas, J; Kapur, R P; Stevens, A M

    2007-01-01

    Toll-like receptor 4 (TLR4) mediates lipopolysaccharide (LPS) induced immune responses, which may contribute to preterm labor associated with intraamniotic gram-negative bacterial infections. The study objective was to investigate gestational age and LPS-induced changes in TLR4 subcellular localization within amniotic epithelium, the first line of host defense against intraamniotic bacteria. TLR4 localization in amniotic epithelium was assessed using immunohistochemistry on 24 placentas of different gestational ages: first trimester (n=6), second trimester (n=6), and third trimester (n=12). Immunofluorescence was used to determine TLR4 localization following ex vivo LPS stimulation of amnion from women undergoing cesarean section without labor at term. TLR4 was expressed in the cytoplasm of amniotic epithelium starting at 9weeks with apical polarization by 25weeks gestation. TLR4 localization to the basal membrane was significantly associated with chorioamnionitis (p=0.01). After LPS stimulation, TLR4 was expressed sequentially within the apical membrane, cytoplasm, and finally in the basal cellular compartment. This suggests that TLR4 expression in amniotic epithelium is poised to monitor amniotic fluid for pathogens. TLR4 translocation to the basal membrane may decrease LPS signaling early in an infection, but allow the amniotic epithelium to remain competent to invasive or intracellular bacteria. PMID:17055575

  18. Antioxidant, inhibition of ?-glucosidase and suppression of nitric oxide production in LPS-induced murine macrophages by different fractions of Actinidia arguta stem.

    PubMed

    Lee, Jaehak; Sowndhararajan, Kandhasamy; Kim, Mihae; Kim, Jaehun; Kim, Daeho; Kim, Sunpyo; Kim, Gur-Yoo; Kim, Songmun; Jhoo, Jin-Woo

    2014-12-01

    In traditional systems of medicine, fruits, leaves, and stems of Actinidia arguta (Sieb. et Zucc.) Planch. ex Miq. have been used to treat various inflammatory diseases. The present study determined the proximate composition, antioxidant, anti-inflammatory, and hypoglycemic potential of A. arguta stem. Phenolic composition of hot water extract and its sub-fractions was determined by Folin-Ciocalteu's reagent method. In vitro antioxidant activities of the samples were evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging assays. Anti-inflammatory activity of different fractions was investigated through the inhibition of nitric oxide (NO) production in lipopolysaccharide (1 ?g/ml) stimulated RAW 264.7 cells. In addition, inhibition of ?-glucosidase activity of hot water extract was determined using p-nitrophenyl-?-d-glucopyranoside (pNPG) as a substrate. Ethyl acetate (557.23 mg GAE/g) fraction contains higher level of total phenolic content. The antioxidant activity evaluated by DPPH radical scavenging assay showed a strong activity for ethyl acetate (IC50 of 14.28 ?g/ml) and n-butanol fractions (IC50 of 48.27 ?g/ml). Further, ethyl acetate fraction effectively inhibited NO production in RAW 264.7 cells induced by lipopolysaccharide (LPS) than other fractions (nitrite level to 32.14 ?M at 200 ?g/ml). In addition, hot water extract of A. arguta stem exhibited appreciable inhibitory activity against ?-glucosidase enzyme with IC50 of 1.71 mg/ml. The obtained results have important consequence of using A. arguta stem toward the development of effective anti-inflammatory drugs. PMID:25473361

  19. Magnolol inhibits LPS-induced inflammatory response in uterine epithelial cells : magnolol inhibits LPS-induced inflammatory response.

    PubMed

    Luo, Jia; Xu, Yanwen; Zhang, Minfang; Gao, Ling; Fang, Cong; Zhou, Canquan

    2013-10-01

    Endometritis is an inflammation of the uterine lining that is commonly initiated at parturition. The uterine epithelial cells play an important role in defending against invading pathogens. Magnolol, a hydroxylated biphenyl compound isolated from Magnolia officinalis, has been shown to have anti-inflammatory effects. The aim of this study was to investigate the anti-inflammatory effect of magnolol in modifying lipopolysaccharide (LPS)-induced signal pathways in mouse uterine epithelial cells. We found that magnolol inhibited TNF-? and IL-6 production in LPS-stimulated mouse uterine epithelial cells. We also found that magnolol inhibited LPS-induced NF-?B activation, I?B? degradation, phosphorylation of ERK, JNK, and P38. Furthermore, magnolol could significantly inhibit the expression of TLR4 stimulating by LPS. These results suggest that magnolol exerts an anti-inflammatory property by downregulating the expression of TLR4 upregulated by LPS, thereby attenuating TLR4-mediated NF-?B and MAPK signaling and the release of pro-inflammatory cytokines. These findings suggest that magnolol may be a therapeutic agent against endometritis. PMID:23515857

  20. Carabrol suppresses LPS-induced nitric oxide synthase expression by inactivation of p38 and JNK via inhibition of I-{kappa}B{alpha} degradation in RAW 264.7 cells

    SciTech Connect

    Lee, Hwa Jin [Department of Life Science, Research Center for Women's Diseases, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of)] [Department of Life Science, Research Center for Women's Diseases, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of); Lim, Hyo Jin; Lee, Da Yeon [College of Pharmacy, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of)] [College of Pharmacy, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of); Jung, Hyeyoun [Department of Life Science, Research Center for Women's Diseases, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of)] [Department of Life Science, Research Center for Women's Diseases, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of); Kim, Mi-Ran; Moon, Dong-Cheul [College of Pharmacy, Chungbuk National University, Cheungju 361-763 (Korea, Republic of)] [College of Pharmacy, Chungbuk National University, Cheungju 361-763 (Korea, Republic of); Kim, Keun Il; Lee, Myeong-Sok [Department of Life Science, Research Center for Women's Diseases, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of)] [Department of Life Science, Research Center for Women's Diseases, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of); Ryu, Jae-Ha, E-mail: ryuha@sookmyung.ac.kr [College of Pharmacy, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of)] [College of Pharmacy, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of)

    2010-01-15

    Carabrol, isolated from Carpesium macrocephalum, showed anti-inflammatory potential in LPS-induced RAW 264.7 murine macrophages. In present study, carabrol demonstrated the inhibitory activity on pro-inflammatory cytokines such as IL-1{beta}, IL-6 and TNF-{alpha}. In addition, mRNA and protein levels of iNOS and COX-2 were reduced by carabrol. Molecular analysis revealed that these suppressive effects were correlated with the inactivation of p38 and JNK via inhibition of NF-{kappa}B activation. Immunoblotting showed that carabrol suppressed LPS-induced degradation of I-{kappa}B{alpha} and decreased nuclear translocation of p65. Taken together, these results suggest that carabrol can be a modulator of pro-inflammatory signal transduction pathway in RAW 264.7 cells.

  1. The Effect of the Aerial Part of Lindera akoensis on Lipopolysaccharides (LPS)-Induced Nitric Oxide Production in RAW264.7 Cells

    PubMed Central

    Yang, Chung-Ping; Huang, Guan-Jhong; Huang, Hui-Chi; Chen, Yu-Chang; Chang, Chi-I; Wang, Sheng-Yang; Chang, Hsun-Shuo; Tseng, Yen-Hsueh; Chien, Shih-Chang; Kuo, Yueh-Hsiung

    2013-01-01

    Four new secondary metabolites, 3?-((E)-Dodec-1-enyl)-4?-hydroxy-5?-methyldihydrofuran-2-one (1), linderinol (6), 4?-O-methylkaempferol 3-O-?-l-(4?-E-p-coumaroyl)rhamnoside (11) and kaempferol 3-O-?-l-(4?-Z-p-coumaroyl) rhamnoside (12) with eleven known compounds—3-epilistenolide D1 (2), 3-epilistenolide D2 (3), (3Z,4?,5?)-3-(dodec-11-ynylidene)-4-hydroxy-5-methylbutanolide (4), (3E,4?,5?)-3-(dodec-11-ynylidene)-4-hydroxy-5-methylbutanolide (5), matairesinol (7), syringaresinol (8), (+)-pinoresinol (9), salicifoliol (10), 4?-p-coumaroylafzelin (13), catechin (14) and epicatechin (15)—were first isolated from the aerial part of Lindera akoensis. Their structures were determined by detailed analysis of 1D- and 2D-NMR spectroscopic data. All of the compounds isolated from Lindera akoensis showed that in vitro anti-inflammatory activity decreases the LPS-stimulated production of nitric oxide (NO) in RAW 264.7 cell, with IC50 values of 4.1–413.8 ?M. PMID:23624606

  2. Macelignan attenuates LPS-induced inflammation and reduces LPS-induced spatial learning impairments in rats.

    PubMed

    Cui, Chun-Ai; Jin, Da-Qing; Hwang, Yoo Kyeong; Lee, Im-Soon; Hwang, Jae Kwan; Ha, Ilho; Han, Jung-Soo

    2008-12-19

    Previous studies have shown that macelignan has anti-inflammatory and neuroprotective effects. Subsequently, in the current study, we demonstrate that oral administrations of macelignan reduce the hippocampal microglial activation induced by chronic infusions of lipopolysaccharide (LPS) into the fourth ventricle of Fisher-344 rat brains. A Morris water maze was used to evaluate the status of the hippocampal-dependent spatial learning in control rats with an artificial cerebrospinal fluid infusion, rats with chronic LPS infusions, and rats with chronic LPS infusions and oral administrations of macelignan. The rats with chronic LPS infusions showed spatial memory impairments relative to the control rats in the performance of the memory task. Daily administration of macelignan reduced the spatial memory impairments induced by the chronic LPS infusions. The results indicate that macelignan may possess therapeutic potential for the prevention of Alzheimer's disease. PMID:18940231

  3. Macelignan attenuates LPS-induced inflammation and reduces LPS-induced spatial learning impairments in rats

    Microsoft Academic Search

    Chun-Ai Cui; Da-Qing Jin; Yoo Kyeong Hwang; Im-Soon Lee; Jae Kwan Hwang; Ilho Ha; Jung-Soo Han

    2008-01-01

    Previous studies have shown that macelignan has anti-inflammatory and neuroprotective effects. Subsequently, in the current study, we demonstrate that oral administrations of macelignan reduce the hippocampal microglial activation induced by chronic infusions of lipopolysaccharide (LPS) into the fourth ventricle of Fisher-344 rat brains. A Morris water maze was used to evaluate the status of the hippocampal-dependent spatial learning in control

  4. Suppression of LPS-induced inflammatory responses by inflexanin B in BV2 microglial cells.

    PubMed

    Lim, Ji-Youn; Sul, Donggeun; Hwang, Bang Yeon; Hwang, Kwang Woo; Yoo, Ki-Yeol; Park, So-Young

    2013-02-01

    Microglia are a type of resident macrophage that functions as an inflammation modulator in the central nervous system. Over-activation of microglia by a range of stimuli disrupts the physiological homeostasis of the brain, and induces inflammatory response and degenerative processes, such as those implicated in neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease. Therefore, we investigated the possible anti-inflammatory mechanisms of inflexanin B in murine microglial BV2 cells. Lipopolysaccharide (LPS) activated BV2 cells and induced the production of pro-inflammatory mediators such as nitric oxide (NO), prostaglandin E2 (PGE2), and cytokines (interleukins-1? and -6, and tumour necrosis factor ?). The LPS-induced production of pro-inflammatory mediators was associated with the enhancement of nuclear factor-kappaB (NF-?B) nuclear translocation and the activation of mitogen-activated protein kinase (MAPK) including ERK1/2 and JNK. Conversely, pretreatment of cells with inflexanin B (10 and 20 ?g/mL) significantly reduced the production of pro-inflammatory mediators. This was accompanied with the reduced nuclear translocation of NF-?B and reduced activation of MAPKs. These results suggest that inflexanin B attenuated the LPS-induced inflammatory process by inhibiting the activation of NF-?B and MAPKs. PMID:23458198

  5. Oleuropein suppresses LPS-induced inflammatory responses in RAW 264.7 cell and zebrafish.

    PubMed

    Ryu, Su-Jung; Choi, Hyeon-Son; Yoon, Kye-Yoon; Lee, Ok-Hwan; Kim, Kui-Jin; Lee, Boo-Yong

    2015-02-25

    Oleuropein is one of the primary phenolic compounds present in olive leaf. In this study, the anti-inflammatory effect of oleuropein was investigated using lipopolysaccharide (LPS)-stimulated RAW 264.7 and a zebrafish model. The inhibitory effect of oleuropein on LPS-induced NO production in macrophages was supported by the suppression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). In addition, our enzyme immunoassay showed that oleuropein suppressed the release of pro-inflammatory cytokines such as interleukin-1? (IL-1?) and interleukin-6 (IL-6). Oleuropein inhibited the translocation of p65 by suppressing phosphorylation of inhibitory kappa B-? (I?B-?). Oleuropein also decreased activation of ERK1/2 and JNK, which are associated with LPS-induced inflammation, and its downstream gene of AP-1. Furthermore, oleuropein inhibited LPS-stimulated NO generation in a zebrafish model. Taken together, our results demonstrated that oleuropein could reduce inflammatory responses by inhibiting TLR and MAPK signaling, and may be used as an anti-inflammatory agent. PMID:25613688

  6. SOCS1\\/JAB Is a Negative Regulator of LPS-Induced Macrophage Activation

    Microsoft Academic Search

    Ichiko Kinjyo; Toshikatsu Hanada; Kyoko Inagaki-Ohara; Hiroyuki Mori; Daisuke Aki; Masanobu Ohishi; Hiroki Yoshida; Masato Kubo; Akihiko Yoshimura

    2002-01-01

    Bacterial lipopolysaccharide (LPS) triggers innate immune responses through Toll-like receptor (TLR) 4. We show here that the suppressor of cytokine-signaling-1 (SOCS1\\/JAB) is rapidly induced by LPS and negatively regulates LPS signaling. SOCS1+\\/? mice or SOCS1?\\/? mice with interferon-? (IFN?)-deficient background were more sensitive to LPS-induced lethal effects than were wild-type littermates. LPS-induced NO2? synthesis and TNF? production were augmented in

  7. MEMANTINE PROTECTS AGAINST LPS-INDUCED NEUROINFLAMMATION, RESTORES BEHAVIORALLY-INDUCED GENE

    E-print Network

    Wenk, Gary

    , autism, Down syndrome, HIV de- mentia, and demyelinating diseases, such as multiple scle- rosisMEMANTINE PROTECTS AGAINST LPS-INDUCED NEUROINFLAMMATION, RESTORES BEHAVIORALLY-INDUCED GENE-induced expression of the im- mediate early gene Arc, indicating altered network activity. LPS is known to activate

  8. Eriobotryae folium extract suppresses LPS-induced iNOS and COX-2 expression by inhibition of NF-kappaB and MAPK activation in murine macrophages.

    PubMed

    Uto, Takuhiro; Suangkaew, Natnaprach; Morinaga, Osamu; Kariyazono, Hiroko; Oiso, Shigeru; Shoyama, Yukihiro

    2010-01-01

    Eriobotryae folium (EF), the dried leaves of Eriobotrya japonica (Thunb.) Lindl. has been traditionally used to treat various diseases such as chronic bronchitis, cough, inflammation, skin diseases, and diabetes. In this study, we examined the effects of Eriobotryae folium extract (EFE) on lipopolysaccharide (LPS)-induced production of nitric oxide (NO) and prostaglandin E2(PGE2) in RAW264 murine macrophage cells. EFE suppressed LPS-induced NO and PGE2 production in a dose-dependent manner. Consistent with these observations, EFE reduced the LPS-induced expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at both protein and mRNA levels. Furthermore, EFE significantly inhibited LPS-induced NF-kappaB binding activity, which was associated with the inhibition of IkappaB-alpha degradation. EFE also attenuated LPS-induced phosphorylation of mitogen-activated protein kinases (MAPKs) including extracellular signal-regulated kinase (ERK), p38 MAPK and c-Jun N-terminal kinase (JNK). These results suggest that the anti-inflammatory properties of EF might result from inhibition of iNOS and COX-2 expression through the downregulation of NF-kappaB activation and MAPK phosphorylation in LPS-stimulated RAW264 cells. PMID:20821828

  9. Taraxerol inhibits LPS-induced inflammatory responses through suppression of TAK1 and Akt activation.

    PubMed

    Yao, Xiangyang; Li, Guilan; Bai, Qin; Xu, Hui; Lü, Chaotian

    2013-02-01

    Taraxerol, a triterpenoid compound, has potent anti-inflammatory effects. However, the molecular mechanisms are not clear. In the study, taraxerol concentration dependently inhibited nitric-oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the protein and mRNA levels and these inhibitions decreased the production of nitric oxide (NO), prostaglandin 2 (PGE2), tumor necrosis factor-? (TNF-?), interleukin (IL)-6, and IL-1? induced by LPS. Furthermore, we found that taraxerol suppressed translocation of nuclear factor-?B (NF-?B), phosphorylation of I?B?, blocked the I?B? degradation as well as IKK and mitogen-activated protein kinase (MAPK) activation by inactivation of TGF-?-activated kinase-1 (TAK1) and Akt. In addition, taraxerol significantly inhibited the formation of TAK1/TAK-binding protein1 (TAB1), which was accompanied by inducing degradation of TAK1, decreasing LPS-induced polyubiquitination of TAK1 as well as TAK1 phosphorylation. Taken together, our data suggest that taraxerol downregulates the expression of proinflammatory mediators in macrophages by interfering with the activation of TAK1 and Akt, thus preventing NF-?B activation. PMID:23333629

  10. Protective effect of taraxasterol against LPS-induced endotoxic shock by modulating inflammatory responses in mice.

    PubMed

    Zhang, Xuemei; Xiong, Huanzhang; Li, Hongyu; Cheng, Yao

    2014-02-01

    Taraxasterol, a pentacyclic-triterpene, was isolated from the Chinese medicinal herb Taraxacum officinale. In the present study, we investigated the protective effect of taraxasterol on murine model of endotoxic shock and the mechanism of its action. Mice were treated with 2.5, 5 and 10 mg/kg of taraxasterol prior to a lethal dose of lipopolysaccharide (LPS) challenge. Survival of mice was monitored twice a day for 7 days. To further understand the mechanism, the serum levels of inflammatory cytokine tumor necrosis factor-? (TNF-?), interferon-? (IFN-?), interleukin-1? (IL-1?), interleukin-6 (IL-6) and mediator nitric oxide (NO), prostaglandin E? (PGE?) as well as histology of lungs were examined. The results showed that taraxasterol significantly improved mouse survival and attenuated tissue injury of the lungs in LPS-induced endotoxemic mice. Further studies revealed that taraxasterol significantly reduced TNF-?, IFN-?, IL-1?, IL-6, NO and PGE? levels in sera from mice with endotoxic shock. These results indicate that taraxasterol has a protective effect on murine endotoxic shock induced by LPS through modulating inflammatory cytokine and mediator secretion. This finding might provide a new strategy for the treatment of endotoxic shock and associated inflammation. PMID:24286370

  11. CXC chemokine GRO is essential for neutrophil infiltration in LPS-induced uveitis in rabbits.

    PubMed

    Mo, J S; Matsukawa, A; Ohkawara, S; Yoshinaga, M

    2000-02-01

    The purpose of this study was to investigate the role and regulation of the CXC chemokine GRO and the interaction between GRO and IL-8 in LPS-induced uveitis in rabbits. Uveitis was induced by intravitreal injection of 100 ng of LPS in rabbits. After the LPS injection, GRO was produced in aqueous humor and peaked at 24 hr. Immunohistochemistry showed that ciliary epithelial cells were responsible for production of GRO. Blocking the activity of GRO by anti-GRO serum reduced LPS-induced aqueous neutrophil counts by 80%, but did not reduce the mononuclear cell counts or protein levels or IL-8 levels. Regulation of GRO production by TNFalpha, IL-1 and IL-8 was studied. Anti-TNFalphamAb alone did not inhibit the 24 hr LPS induced GRO levels, whereas rrIL-1Ra inhibited the GRO production by 58%. The combination of anti-TNFalpha mAb and rrIL-1Ra inhibited 93% of GRO production. Although treatment with anti-IL-8 IgG inhibited the neutrophil infiltration by 66%, treatment with this antibody did not inhibit GRO production. Taken together, our results suggest that GRO is an essential mediator for neutrophil infiltration in LPS-induced uveitis in rabbits. Most of GRO production is mediated by TNFalpha and IL-1. GRO and IL-8 act in concert to mediate neutrophil infiltration. PMID:10655148

  12. Low-Level Laser Therapy Attenuates LPS-Induced Rats Mastitis by Inhibiting Polymorphonuclear Neutrophil Adhesion

    PubMed Central

    WANG, Yueqiang; HE, Xianjing; HAO, Dandan; YU, Debin; LIANG, Jianbin; QU, Yanpeng; SUN, Dongbo; YANG, Bin; YANG, Keli; WU, Rui; WANG, Jianfa

    2014-01-01

    ABSTRACT The aim of this study was to investigate the effects of low-level laser therapy (LLLT) on a rat model of lipopolysaccharide (LPS)-induced mastitis and its underlying molecular mechanisms. The rat model of mastitis was induced by inoculation of LPS through the canals of the mammary gland. The results showed that LPS-induced secretion of IL-1? and IL-8 significantly decreased after LLLT (650 nm, 2.5 mW, 30 mW/cm2). LLLT also inhibited intercellular adhesion molecule-1 (ICAM-1) expression and attenuated the LPS-induced decrease of the expression of CD62L and increase of the expression of CD11b. Moreover, LLLT also suppressed LPS-induced polymorphonuclear neutrophils (PMNs) entering the alveoli of the mammary gland. The number of PMNs in the mammary alveolus and the myeloperoxidase (MPO) activity were decreased after LLLT. These results suggested that LLLT therapy is beneficial in decreasing the somatic cell count and improving milk nutritional quality in cows with an intramammary infection. PMID:25452258

  13. NEUTROPHILS PLAY A CRITICAL ROLE IN THE DEVELOPMENT OF LPS-INDUCED AIRWAY DISEASE

    EPA Science Inventory

    ETD-02-045 (GAVETT) GPRA # 10108 Neutrophils Play a Critical Role in the Development of LPS-Induced Airway Disease. Jordan D. Savov, Stephen H. Gavett*, David M. Brass, Daniel L. Costa*, and David A. Schwartz ABSTRACT We investigated the role of neutrophils...

  14. Emodin inhibits LPS-induced inflammatory response by activating PPAR-? in mouse mammary epithelial cells.

    PubMed

    Yang, Zhengtao; Zhou, Ershun; Wei, Dong; Li, Depeng; Wei, Zhengkai; Zhang, Wen; Zhang, Xichen

    2014-08-01

    Emodin, an anthraquinone derivative isolated from the rhizomes of Rheum palmatum, has been reported to have a protective effect against lipopolysaccharide (LPS)-induced mastitis. However, the underlying molecular mechanisms are not well understood. The aim of this study was to investigate the molecular mechanisms of emodin in modifying lipopolysaccharide (LPS)-induced signaling pathways in mouse mammary epithelial cells (MEC). The pro-inflammatory cytokines were determined by ELISA. Nuclear factor-?B (NF-?B), inhibitory kappa B (I?B?) protein, p38, extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and PPAR-? were determined by Western blotting. The results showed that emodin suppressed tumor necrosis factor-alpha (TNF-?), interleukin-6 (IL-6), iNOS and COX-2 expression. We also found that emodin inhibited LPS-induced NF-?B activation, I?B? degradation, phosphorylation of ERK, JNK and P38. Furthermore, emodin could activate PPAR-? and the anti-inflammatory effects of emodin can be reversed by GW9662, a specific antagonist for PPAR-?. In conclusion, our results demonstrate that emodin activates PPAR-?, thereby attenuating LPS-induced inflammatory response. PMID:24874440

  15. Treatment with the hyaluronic Acid synthesis inhibitor 4-methylumbelliferone suppresses LPS-induced lung inflammation.

    PubMed

    McKallip, Robert J; Ban, Hao; Uchakina, Olga N

    2015-06-01

    Exposure to bacterial endotoxins, such as lipopolysaccharide (LPS), can lead to the induction of acute lung injury/acute respiratory distress syndrome (ALI/ARDS). To date, there are no known effective treatments for LPS-induced inflammation. In the current study, we investigated the potential use of the hyaluronic acid (HA) synthesis inhibitor 4-methylumbelliferone (4-MU) on LPS-induced acute lung inflammation. Culturing LPS-activated immune cells with 4-MU led to reduced proliferation, reduced cytokine production, and an increase in apoptosis when compared to untreated cells. Treatment of mice with 4-MU led to protection from LPS-induced lung injury. Specifically, 4-MU treatment led to a reduction in LPS-induced hyaluronic acid synthase (HAS) messenger RNA (mRNA) levels, reduction in lung permeability, and reduction in proinflammatory cytokine production. Taken together, these results suggest that use of 4-MU to target HA production may be an effective treatment for the inflammatory response following exposure to LPS. PMID:25537799

  16. EFFECTS OF SYSTEMIC NEUTROPHIL DEPLETION ON LPS-INDUCED AIRWAY DISEASE

    EPA Science Inventory

    Effects of Systemic Neutrophil Depletion on LPS-induced Airway Disease Jordan D. Savov, Stephen H. Gavett*, David M. Brass, Daniel L. Costa*, David A. Schwartz Pulmonary and Critical Care Division, Dept of Medicine ? Duke University Medical Center * National Health and E...

  17. Role and regulation of IL-8 and MCP-1 in LPS-induced uveitis in rabbits.

    PubMed

    Mo, J S; Matsukawa, A; Ohkawara, S; Yoshinaga, M

    1999-03-01

    Intravitreal injection of lipopolysaccharide (LPS) induces leukocyte infiltration and protein leakage into the aqueous humor. In the present study, we investigated the role of IL-8 and MCP-1 and regulation of these chemokines by TNFalpha and IL-1 in LPS-induced uveitis in rabbits. After intravitreal injection of LPS, generation of IL-8 in the aqueous humor showed a biphasic pattern with the first peak at 12 hr and the second one at 24 hr, while MCP-1 was produced in a monophasic pattern and peaked at 24 hr. Immunohistochemistry showed that ciliary epithelial cells and infiltrating leukocytes were the producing cells of IL-8 and MCP-1. Administration of anti-IL-8 IgG suppressed by 66% the peak levels of LPS-induced aqueous neutrophil counts at 24 hr but did not suppress aqueous mononuclear cell counts or protein levels. anti-MCP-1 IgG inhibited aqueous mononuclear cell counts by 41% and protein levels by 28%, but did not inhibit aqueous neutrophil counts. The levels of LPS-induced aqueous IL-8 and MCP-1 at 12 hr were inhibited by anti-TNFalpha mAb but not by an IL-1 receptor antagonist (IL-1Ra), while concentrations of the two chemokines at 24 hr were inhibited by both anti-TNFalpha mAb and IL-1Ra. A combination of anti-TNFalpha mAb and rrIL-1Ra had an additive effect on the 24 hr-chemokine levels and inhibited up to 90% chemokine production. Taken together, our results show that IL-8 mediates neutrophil infiltration, while MCP-1 mediates mononuclear cell infiltration and protein leakage in LPS-induced uveitis in rabbits. Levels of aqueous IL-8 and MCP-1 at 12 hr are regulated by TNFalpha, while levels at 24 hr are regulated by TNFalpha and IL-1. PMID:10079141

  18. Effects of voluntary wheel running on LPS-induced sickness behavior in aged mice.

    PubMed

    Martin, Stephen A; Pence, Brandt D; Greene, Ryan M; Johnson, Stephanie J; Dantzer, Robert; Kelley, Keith W; Woods, Jeffrey A

    2013-03-01

    Peripheral stimulation of the innate immune system with LPS causes exaggerated neuroinflammation and prolonged sickness behavior in aged mice. Regular moderate intensity exercise has been shown to exert anti-inflammatory effects that may protect against inappropriate neuroinflammation and sickness in aged mice. The purpose of this study was to test the hypothesis that voluntary wheel running would attenuate LPS-induced sickness behavior and proinflammatory cytokine gene expression in ~22-month-old C57BL/6J mice. Mice were housed with a running wheel (VWR), locked-wheel (Locked), or no wheel (Standard) for 10 weeks, after which they were intraperitoneally injected with LPS across a range of doses (0.02, 0.08, 0.16, 0.33 mg/kg). VWR mice ran on average 3.5 km/day and lost significantly more body weight and body fat, and increased their forced exercise tolerance compared to Locked and Shoebox mice. VWR had no effect on LPS-induced anorexia, adipsia, weight-loss, or reductions in locomotor activity at any LPS dose when compared to Locked and Shoebox groups. LPS induced sickness behavior in a dose-dependent fashion (0.33>0.02 mg/kg). Twenty-four hours post-injection (0.33 mg/kg LPS or Saline) we found a LPS-induced upregulation of whole brain TNF?, IL-1?, and IL-10 mRNA, and increased IL-1? and IL-6 in the spleen and liver; these effects were not attenuated by VWR. We conclude that VWR does not reduce LPS-induced exaggerated or prolonged sickness behavior in aged animals, or 24h post-injection (0.33 mg/kg LPS or Saline) brain and peripheral proinflammatory cytokine gene expression. The necessity of the sickness response is critical for survival and may outweigh the subtle benefits of exercise training in aged animals. PMID:23277090

  19. Augmentation of LPS-induced vascular endothelial cell growth factor production in macrophages by transforming growth factor-?1.

    PubMed

    Koide, Naoki; Odkhuu, Erdenezaya; Naiki, Yoshikazu; Tsolmongyn, Bilegtsaikhan; Ito, Kiyoaki; Komatsu, Takayuki; Yoshida, Tomoaki; Yokochi, Takashi

    2014-11-01

    The effect of LPS on the production of vascular endothelial growth factor (VEGF) was examined using RAW 264.7 macrophage cells. LPS induced VEGF production in RAW 264.7 cells and mouse peritoneal cells. LPS induced VEGF production via the expression of hypoxia inducible factor-1? and LPS-induced VEGF production was dependent on the activation of p38 MAPK and NF-?B activation· Transforming growth factor (TGF)-?1 augmented LPS-induced VEGF production, although TGF-?1 alone did not induce VEGF production. The augmentation of LPS-induced VEGF production by TGF-?1 was inhibited by a p38 MAPK inhibitor and was correlated with the phosphorylation of Smad3. The enhancing effect of TGF-?1 on LPS-induced VEGF production was observed in vivo in the skin lesions of mice receiving a subcutaneous injection of LPS. Taken together, it is suggested that LPS induced the VEGF production in macrophages and that it was augmented by TGF-?1 in vitro and in vivo. PMID:24225655

  20. Leonurine exerts anti-inflammatory effect by regulating inflammatory signaling pathways and cytokines in LPS-induced mouse mastitis.

    PubMed

    Song, Xiaojing; Wang, Tiancheng; Zhang, Zecai; Jiang, Haichao; Wang, Wei; Cao, Yongguo; Zhang, Naisheng

    2015-02-01

    Bovine mastitis is defined as the inflammation of mammary gland and is the most multiple diseases in dairy cattle. There is still no effective treatment now. Leonurine, extracted from Leonurus cardiaca, has been proved to have anti-inflammatory effect. In the present study, we utilized a mouse mastitis model to study the effect of leonurine on LPS-induced mastitis. Leonurine was administered three times during the 24 h after inducing infection in the mammary gland. The results showed that leonurine significantly alleviated LPS-induced histopathological changes, downregulated the levels of pro-inflammatory cytokines tumor necrosis factor-? (TNF-?), interleukin-6 (IL-6), upregulated the level of anti-inflammatory cytokine interleukin-10 (IL-10), and inhibited the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Further study revealed that leonurine inhibited the expression of Toll-like receptor 4 (TLR4) and the activation of nuclear factor-kappaB (NF-?B) and the phosphorylation of p38, extracellular signal-regulated kinase (ERK), and Jun N-terminal kinase (JNK). Therefore, the results demonstrated that leonurine could downregulate the expression of TNF-?, IL-6, iNOS, and COX-2 and upregulate the expression of IL-10 mainly by inhibiting the expression of TLR4 and the activation of NF-?B and the phosphorylation of p38, ERK, and JNK. Leonurine may be a potential agent for mastitis therapy. PMID:25189466

  1. Epigallocatechin-3-gallate Inhibits LPS-Induced NF-?B and MAPK Signaling Pathways in Bone Marrow-Derived Macrophages

    PubMed Central

    Joo, So-Young; Song, Young-A; Park, Young-Lan; Myung, Eun; Chung, Cho-Yun; Park, Kang-Jin; Cho, Sung-Bum; Lee, Wan-Sik; Kim, Hyun-Soo; Rew, Jong-Sun; Kim, Nack-Sung

    2012-01-01

    Background/Aims Epigallocatechin-3-gallate (EGCG), the primary catechin in green tea, has anti-inflammatory and anti-oxidative properties. The aim of the current study was to characterize the impact of EGCG on lipopolysaccharide (LPS)-induced innate signaling in bone marrow-derived macrophages (BMMs) isolated from ICR mice. Methods The effect of EGCG on LPS-induced pro-inflammatory gene expression and nuclear factor-?B (NF-?B) and mitogen-activated protein kinase (MAPK) signaling was examined using reverse transcription-polymerase chain reaction, Western blotting, immunofluorescence, and the electrophoretic mobility shift assay. Results EGCG inhibited accumulation of LPS-induced IL-12p40, IL-6, MCP-1, ICAM-1, and VCAM-1 mRNA in BMMs. EGCG blocked LPS-induced I?B? degradation and RelA nuclear translocation. EGCG blocked the DNA-binding activity of NF-?B. LPS-induced phosphorylation of ERK1/2, JNK, and p38 was inhibited by EGCG. U0126 (an inhibitor of MEK-1/2) suppressed the LPS-induced IL-12p40, IL-6, MCP-1, ICAM-1, and VCAM-1 mRNA accumulation in BMMs. Conclusions These results indicate that EGCG may prevent LPS-induced pro-inflammatory gene expression through blocking NF-?B and MAPK signaling pathways in BMMs. PMID:22570747

  2. Effects of cannabinoid receptor ligands on LPS-induced pulmonary inflammation in mice

    Microsoft Academic Search

    E. Berdyshev; E. Boichot; M. Corbel; N. Germain; V Lagente

    1998-01-01

    The effects of cannabinoid receptor agonists WIN 55,212-2, ?9-tetrahydrocannabinol (?9-THC), arachidonoylethanolamide (anandamide) and palmitoylethanolamide on lipopolysaccharide (LPS) -induced bronchopulmonary inflammation in mice were investigated. WIN 55,212-2 and ?9-THC induced a concentration-dependent decrease in TNF-? level in the bronchoalveolar lavage fluid (BALF) (maximum inhibition 52.7% and 36.9% for intranasal doses of 750 nmol.kg?1 and 2.65 mmol.kg?1, respectively). This effect was accompanied

  3. Role of tumor necrosis factor-? and glucocorticoid on lipopolysaccharide (LPS)-induced apoptosis of thymocytes

    Microsoft Academic Search

    Y. Kato; A. Morikawa; T. Sugiyama; N. Koide; G. Z. Jiang; K. Takahashi; T. Yokochi

    1995-01-01

    Administration of bacterial lipopolysaccharide (LPS) into mice markedly induced the apoptosis of CD4+8+ thymocytes. The injection of anti-tumor necrosis factor (TNF)-? antibody or RU38486, a glucocorticoid receptor antagonist, into mice definitely inhibited LPS-induced apoptosis of thymocytes. Addition of the sera 1 h after injection of LPS into in vitro cultures of thymocytes caused thymocyte apoptosis. It was also prevented by

  4. DUOX-Mediated Signaling Is Not Required for LPS-Induced Neutrophilic Response in the Airways

    PubMed Central

    Chang, Sandra; Linderholm, Angela; Harper, Richart

    2015-01-01

    Oxidant production from DUOX1 has been proposed to lead to neutrophil recruitment into the airways when lung homeostasis is compromised. The objective of this study was to determine whether DUOX-derived hydrogen peroxide is required for LPS-induced neutrophil recruitment, using a functional DUOX knock out mouse model. We found that LPS induced profound neutrophilic lung inflammation in both Duoxa+/+ and Duoxa-/- mice between 3h and 24h. Duoxa-/- mice had significantly higher neutrophil influx 24h after LPS instillation despite similar cytokine levels (KC, MIP-2, or TGF-?) between the two groups. These findings suggest that LPS-TLR-4-induced KC or MIP-2 cytokine induction and subsequent neutrophil recruitment in the airway does not require DUOX-derived hydrogen peroxide from airway epithelium. PMID:26148206

  5. Inhibition of LPS-induced airway hyperresponsiveness and airway inflammation by LPS antagonists.

    PubMed

    Schwartz, D A; Christ, W J; Kleeberger, S R; Wohlford-Lenane, C L

    2001-04-01

    To determine whether the inflammatory effects of inhaled endotoxin could be prevented, we pretreated mice with synthetic competitive antagonists (975, 1044, and 1287) for lipopolysaccharide (LPS) before a LPS inhalation challenge. In preliminary studies, we found that these LPS antagonists did not act as agonists in vitro (THP-1 cells) or in vivo (after intratracheal instillation of 10 microg) and that these compounds (at least 1 microg/ml) effectively antagonized the release of tumor necrosis factor-alpha by LPS-stimulated THP-1 cells. Pretreatment of mice with 10 microg of either 1044 or 1287 resulted in a decrease in the LPS-induced airway hyperreactivity. Moreover, pretreatment of mice with 10 microg of 975, 1044, or 1287 resulted in significant reductions in LPS-induced lung lavage fluid concentrations of total cells, neutrophils, and specific proinflammatory cytokines compared with mice pretreated with sterile saline. Using residual oil fly ash to induce airway inflammation, we found that the action of the LPS antagonists was specific to LPS-induced airway disease. These results suggest that LPS antagonists may be an effective and potentially safe treatment for endotoxin-induced airway disease. PMID:11238019

  6. Nucleotide receptor P2RX7 stimulation enhances LPS-induced interferon-? production in murine macrophages.

    PubMed

    Gavala, M L; Liu, Y-P; Lenertz, L Y; Zeng, L; Blanchette, J B; Guadarrama, A G; Denlinger, L C; Bertics, P J; Smith, J A

    2013-10-01

    Stimulation of P2RX(7) with extracellular ATP potentiates numerous LPS-induced proinflammatory events, including cytokine induction in macrophages, but the molecular mechanisms underlying this process are not well defined. Although P2RX(7) ligation has been proposed to activate several transcription factors, many of the LPS-induced mediators affected by P2RX(7) activation are not induced by P2RX(7) agonists alone, suggesting a complementary role for P2RX(7) in transcriptional regulation. Type I IFN production, whose expression is tightly controlled by multiple transcription factors that form an enhanceosome, is critical for resistance against LPS-containing bacteria. The effect of purinergic receptor signaling on LPS-dependent type I IFN is unknown and would be of great relevance to a diverse array of inflammatory conditions. The present study demonstrates that stimulation of macrophages with P2RX(7) agonists substantially enhances LPS-induced IFN-? expression, and this enhancement is ablated in macrophages that do not express functional P2RX(7) or when the MAPK MEK1/2 pathways are inhibited. Potentiation of LPS-induced IFN-? expression following P2RX(7) stimulation is likely transcriptionally regulated, as this enhancement is observed at the IFN-? promoter level. Furthermore, P2RX(7) stimulation is able to increase the phosphorylation and subsequent IFN-? promoter occupancy of IRF-3, a transcription factor that is critical for IFN-? transcription by TLR agonists. This newly discovered role for P2RX(7) in IFN regulation may have implications in antimicrobial defense, which has been linked to P2RX(7) activation in other studies. PMID:23911869

  7. Nucleotide receptor P2RX7 stimulation enhances LPS-induced interferon-? production in murine macrophages

    PubMed Central

    Gavala, M. L.; Liu, Y.-P.; Lenertz, L. Y.; Zeng, L.; Blanchette, J. B.; Guadarrama, A. G.; Denlinger, L. C.; Bertics, P. J.; Smith, J. A.

    2013-01-01

    Stimulation of P2RX7 with extracellular ATP potentiates numerous LPS-induced proinflammatory events, including cytokine induction in macrophages, but the molecular mechanisms underlying this process are not well defined. Although P2RX7 ligation has been proposed to activate several transcription factors, many of the LPS-induced mediators affected by P2RX7 activation are not induced by P2RX7 agonists alone, suggesting a complementary role for P2RX7 in transcriptional regulation. Type I IFN production, whose expression is tightly controlled by multiple transcription factors that form an enhanceosome, is critical for resistance against LPS-containing bacteria. The effect of purinergic receptor signaling on LPS-dependent type I IFN is unknown and would be of great relevance to a diverse array of inflammatory conditions. The present study demonstrates that stimulation of macrophages with P2RX7 agonists substantially enhances LPS-induced IFN-? expression, and this enhancement is ablated in macrophages that do not express functional P2RX7 or when the MAPK MEK1/2 pathways are inhibited. Potentiation of LPS-induced IFN-? expression following P2RX7 stimulation is likely transcriptionally regulated, as this enhancement is observed at the IFN-? promoter level. Furthermore, P2RX7 stimulation is able to increase the phosphorylation and subsequent IFN-? promoter occupancy of IRF-3, a transcription factor that is critical for IFN-? transcription by TLR agonists. This newly discovered role for P2RX7 in IFN regulation may have implications in antimicrobial defense, which has been linked to P2RX7 activation in other studies. PMID:23911869

  8. Linalool Inhibits LPS-Induced Inflammation in BV2 Microglia Cells by Activating Nrf2.

    PubMed

    Li, Yang; Lv, Ou; Zhou, Fenggang; Li, Qingsong; Wu, Zhichao; Zheng, Yongri

    2015-07-01

    Linalool, a natural compound of the essential oils, has been reported to have anti-inflammatory effects. This study aimed to investigate the anti-inflammatory effects and mechanism of linalool in LPS-stimulated BV2 microglia cells. BV2 microglia cells were stimulated with LPS in the presence or absence of linalool. The production of inflammatory mediators TNF-?, IL-1?, NO, and PGE2 as well as Nrf2, HO-1 expression were detected. Our results showed that linalool inhibited LPS-induced TNF-?, IL-1?, NO, and PGE2 production in a dose-dependent manner. Linalool also inhibited LPS-induced NF-?B activation. Treatment of linalool induced nuclear translocation of Nrf2 and expression of HO-1. In addition, our results showed that the anti-inflammatory effect of linalool was attenuated by transfection with Nrf2 siRNA. In conclusion, these results suggested that linalool inhibits LPS-induced inflammation in BV2 microglia cells by activating Nrf2/HO-1 signaling pathway. PMID:26040565

  9. Vascular barrier protective effects of pellitorine in LPS-induced inflammation in vitro and in vivo.

    PubMed

    Lee, Wonhwa; Ku, Sae-Kwang; Min, Byung-Woon; Lee, Sangkyu; Jee, Jun-Goo; Kim, Jeong Ah; Bae, Jong-Sup

    2014-01-01

    Pellitorine (PT), an active amide compound, is well known to possess insecticidal, antibacterial and anticancer properties. In this study, we first investigated the possible barrier protective effects of pellitorine against pro-inflammatory responses induced by lipopolysaccharide (LPS) and the associated signaling pathways in vitro and in vivo. The barrier protective activities of PT were determined by measuring permeability, monocyte adhesion and migration, and activation of pro-inflammatory proteins in LPS-activated human umbilical vein endothelial cells (HUVECs) and in mice. We found that PT inhibited LPS-induced barrier disruption, expression of cell adhesion molecules (CAMs) and adhesion/transendothelial migration of monocytes to human endothelial cells. PT also suppressed LPS-induced hyperpermeability and leukocyte migration in vivo. Further studies revealed that PT suppressed the production of tumor necrosis factor-? (TNF-?) or Interleukin (IL)-6 and activation of nuclear factor-?B (NF-?B) or extracellular regulated kinases (ERK) 1/2 by LPS. Moreover, treatment with PT resulted in reduced LPS-induced lethal endotoxemia. These results suggest that PT protects vascular barrier integrity by inhibiting hyperpermeability, expression of CAMs, and adhesion and migration of leukocytes, thereby endorsing its usefulness as a therapy for vascular inflammatory diseases. PMID:24262867

  10. Liver X receptor agonist prevents LPS-induced mastitis in mice.

    PubMed

    Fu, Yunhe; Tian, Yuan; Wei, Zhengkai; Liu, Hui; Song, Xiaojing; Liu, Wenbo; Zhang, Wenlong; Wang, Wei; Cao, Yongguo; Zhang, Naisheng

    2014-10-01

    Liver X receptor-? (LXR-?) which belongs to the nuclear receptor superfamily, is a ligand-activated transcription factor. Best known for its ability to regulate lipid metabolism and transport, LXRs have recently also been implicated in regulation of inflammatory response. The aim of this study was to investigate the preventive effects of synthetic LXR-? agonist T0901317 on LPS-induced mastitis in mice. The mouse model of mastitis was induced by injection of LPS through the duct of mammary gland. T0901317 was injected 1h before and 12h after induction of LPS intraperitoneally. The results showed that T0901317 significantly attenuated the infiltration of neutrophilic granulocytes, and the activation of myeloperoxidase (MPO); down-regulated the level of pro-inflammatory mediators including TNF-?, IL-1?, IL-6, COX-2 and PEG2; inhibited the phosphorylation of I?B-? and NF-?B p65, caused by LPS. Moreover, we report for the first time that LXR-? activation impaired LPS-induced mastitis. Taken together, these data indicated that T0901317 had protective effect on mastitis and the anti-inflammatory mechanism of T0901317 on LPS induced mastitis in mice may be due to its ability to inhibit NF-?B signaling pathway. LXR-? activation can be used as a therapeutic approach to treat mastitis. PMID:25066757

  11. Phosphoinositide-3 kinase ? required for LPS-induced transepithelial neutrophil trafficking in the lung

    PubMed Central

    Reutershan, Jörg; Saprito, Mary S.; Wu, Dan; Rückle, Thomas; Ley, Klaus

    2009-01-01

    Phosphoinositide 3-kinase ? (PI3K?) is a critical mediator of directional cell movement. Here, we sought to characterize the role of PI3K? in mediating the different steps of PMN trafficking in the lung. In a murine model of LPS-induced lung injury, PMN migration into the different lung compartments was determined in PI3K? gene-deficient (PI3K??/?) and wildtype mice. Bone marrow chimeras were created to characterize the role of PI3K? on hematopoietic vs. non-hematopoietic cells. A small molecule PI3K? inhibitor was tested in vitro and in vivo. PMN adhesion to the pulmonary endothelium and transendothelial migration into the lung interstitium was enhanced in PI3K??/? mice. However, transepithelial migration into the alveolar space was reduced in these mice. When irradiated PI3K??/? mice were reconstituted with bone marrow from wildtype mice, migratory activity into the alveolar space was restored partially. A small molecule PI3K? inhibitor reduced chemokine-induced PMN migration in vitro when PMNs or epithelial cells but not when endothelial cells were treated. The inhibitor also reduced LPS-induced PMN migration in vivo. We conclude that PI3K? is required for transepithelial but not for transendothelial migration in LPS-induced lung injury. Inhibition of PI3K? activity may be effective at curbing excessive PMN infiltration in lung injury. PMID:19797129

  12. Barrier protective effects of piperlonguminine in LPS-induced inflammation in vitro and in vivo.

    PubMed

    Lee, Wonhwa; Yoo, Hayoung; Kim, Jeong Ah; Lee, Sangkyu; Jee, Jun-Goo; Lee, Min Young; Lee, You-Mie; Bae, Jong-Sup

    2013-08-01

    Piperlonguminine (PL), an important component of Piper longum fruits, is well known to possess potent anti-hyperlipidemic, anti-platelet and anti-melanogenesis activities. In this study, we first investigated the possible barrier protective effects of piperlonguminine against proinflammatory responses induced by lipopolysaccharide (LPS) and the associated signaling pathways in vitro and in vivo. The barrier protective activities of PL were determined by measuring permeability, monocytes adhesion and migration, and activation of proinflammatory proteins in LPS-activated human umbilical vein endothelial cells (HUVECs) and in mice. We found that PL inhibited LPS-induced barrier disruption, expression of cell adhesion molecules (CAMs) and adhesion/transendothelial migration of monocytes to human endothelial cells. PL also suppressed LPS-induced hyperpermeability and leukocytes migration in vivo. Further studies revealed that PL suppressed the production of tumor necrosis factor-? (TNF-?) or Interleukin (IL)-6 and activation of nuclear factor-?B (NF-?B) or extracellular regulated kinases (ERK) 1/2 by LPS. Moreover, treatment with PL resulted in reduced LPS-induced septic mortality. Collectively, these results suggest that PL protects vascular barrier integrity by inhibiting hyperpermeability, expression of CAMs, adhesion and migration of leukocytes, thereby endorsing its usefulness as a therapy for vascular inflammatory diseases. PMID:23619565

  13. LPS-induced Fos expression in oxytocin and vasopressin neurons of the rat hypothalamus

    Microsoft Academic Search

    Wataru Matsunaga; Seiji Miyata; Akira Takamata; Hiromitsu Bun; Toshihiro Nakashima; Toshikazu Kiyohara

    2000-01-01

    The aim of this study was to examine the involvement of the hypothalamic oxytocin (OXT) and vasopressin (AVP) neurons in acute phase reaction using quantitative dual-labeled immunostaining with Fos and either OXT and AVP in several hypothalamic regions. Administration of low dose (5 ?g\\/kg) and high dose (125 ?g\\/kg) of LPS induced intense nuclear Fos immunoreactivity in many OXT and

  14. Inhibitory effects of orally administrated liposomal bovine lactoferrin on the LPS-induced osteoclastogenesis

    Microsoft Academic Search

    Eizo Yamano; Mutsumi Miyauchi; Hisako Furusyo; Aki Kawazoe; Atsushi Ishikado; Taketoshi Makino; Kazuo Tanne; Eiji Tanaka; Takashi Takata

    2010-01-01

    Bovine lactoferrin (bLF) modulates the production of proinflammatory cytokines including tumor necrosis factor (TNF)-?, and may thus control alveolar bone destruction associated with periodontitis. In this study, the effects of bLF on mRNA expression in lipopolysaccharide (LPS)-stimulated osteoblasts (OBs) and on LPS-induced osteoclastogenesis were examined. The inhibitory effects of oral administration of liposomal-bLF (L-bLF), which improved the robustness of bLF

  15. Cannabidiol improves lung function and inflammation in mice submitted to LPS-induced acute lung injury.

    PubMed

    Ribeiro, A; Almeida, V I; Costola-de-Souza, C; Ferraz-de-Paula, V; Pinheiro, M L; Vitoretti, L B; Gimenes-Junior, J A; Akamine, A T; Crippa, J A; Tavares-de-Lima, W; Palermo-Neto, J

    2015-02-01

    We have previously shown that the prophylactic treatment with cannabidiol (CBD) reduces inflammation in a model of acute lung injury (ALI). In this work we analyzed the effects of the therapeutic treatment with CBD in mice subjected to the model of lipopolysaccharide (LPS)-induced ALI on pulmonary mechanics and inflammation. CBD (20 and 80?mg/kg) was administered (i.p.) to mice 6?h after LPS-induced lung inflammation. One day (24?h) after the induction of inflammation the assessment of pulmonary mechanics and inflammation were analyzed. The results show that CBD decreased total lung resistance and elastance, leukocyte migration into the lungs, myeloperoxidase activity in the lung tissue, protein concentration and production of pro-inflammatory cytokines (TNF and IL-6) and chemokines (MCP-1 and MIP-2) in the bronchoalveolar lavage supernatant. Thus, we conclude that CBD administered therapeutically, i.e. during an ongoing inflammatory process, has a potent anti-inflammatory effect and also improves the lung function in mice submitted to LPS-induced ALI. Therefore the present and previous data suggest that in the future cannabidiol might become a useful therapeutic tool for the attenuation and treatment of inflammatory lung diseases. PMID:25356537

  16. MCPIP1 Negatively Regulates Toll-like Receptor 4 Signaling and Protects Mice from LPS-induced Septic Shock

    PubMed Central

    Huang, Shengping; Miao, Ruidong; Zhou, Zhou; Wang, Tianyi; Liu, Jianguo; Liu, Gang; Chen, Y. Eugene; Xin, Hong-Bo; Zhang, Jifeng; Fu, Mingui

    2013-01-01

    Septic shock is one of leading causes of morbidity and mortality in hospital patients. However, genetic factors predisposing to septic shock are not fully understood. Our previous work showed that MCP-induced protein 1 (MCPIP1) was induced by lipopolysaccharides (LPS), which then negatively regulates LPS-induced inflammatory signaling in vitro. Here we report that although MCPIP1 was induced by various toll-like receptor (TLR) ligands in macrophages, MCPIP1-deficient mice are extremely susceptible to TLR4 ligand (LPS)-induced septic shock and death, but not to the TLR2, 3, 5 and 9 ligands-induced septic shock. Consistently, LPS induced tumor necrosis factor ? (TNF?) production in MCPIP1-deficient mice was 20-fold greater than that in their wild-type littermates. Further analysis revealed that MCPIP1-deficient mice developed severe acute lung injury after LPS injection and JNK signaling was highly activated in MCPIP1-deificient lungs after LPS stimulation. Finally, macrophage-specific MCPIP1 transgenic mice were partially protected from LPS-induced septic shock, suggesting that inflammatory cytokines from sources other than macrophages may significantly contribute to the pathogenesis of LPS-induced septic shock. Taken together, these results suggest that MCPIP1 selectively suppresses TLR4 signaling pathway and protects mice from LPS-induced septic shock. PMID:23422584

  17. Anti-inflammatory effects of chicanine on murine macrophage by down-regulating LPS-induced inflammatory cytokines in I?B?/MAPK/ERK signaling pathways

    PubMed Central

    Chen, Haixia; Sohn, Johann; Zhang, Likang; Tian, Jingge; Chen, Shuhan; Bjeldanes, Leonard F.

    2014-01-01

    Schisandra chinensis Baill is a Chinese traditional medicine with multiple pharmacological activities. In this study, chicanine, one of the major lignan compounds of Schiandra chinesis, was investigated for suppressive effects on lipopolysaccharide (LPS)-induced inflammatory responses in murine macrophages (RAW 264.7 cells). Chicanine was found to have anti-infammatory properties with the inhibition of nitric oxide (NO) and Prostaglandin E (2) (PGE2) production and nuclear factor-?B (NF-?B) signaling in LPS-stimulated RAW 264.7 cells with no cytotoxic effects. Treatment of RAW 264.7 cells with chicanine down-regulated LPS-induced expression of pro-inflammatory cytokines including TNF?, IL-1?, MCP-1, G-CSF, cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). These inhibitory effects were found with the blockage of p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinases 1 and 2 (ERK 1/2), and also I?B-? phosphorylation. These results indicated that anti-inflammatory actions of chicanine in macrophages involved inhibition of LPS-induced TLR4-I?B?/MAPK/ERK signaling pathways. PMID:24361309

  18. Anti-inflammatory activity of the oriental herb medicine, Arisaema cum Bile, in LPS-induced PMA-differentiated THP-1 cells.

    PubMed

    Ahn, Chang-Bum; Je, Jae-Young

    2012-06-01

    Arisaema cum Bile is widely used as a folk medicine in Korea. However, the systematic biological properties of Arisaema cum Bile have seldom been addressed. In this study, we evaluated the anti-inflammatory activity of Arisaema cum Bile extract on lipopolysaccharide (LPS)-induced inflammation in phorbol 12-myristate 13-acetate (PMA)-differentiated THP-1 macrophages. The Arisaema cum Bile extract markedly inhibited the production of pro-inflammatory cytokines including interleukin (IL)-1?, IL-6, and tumor necrosis factor (TNF)-?, and also suppressed the mRNA and protein expressions of these cytokines. Furthermore, the Arisaema cum Bile extract also inhibited LPS-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein and gene expressions in PMA-differentiaed THP-1 macrophages. These results suggest that Arisaema cum Bile extract may have potential for development into an effective anti-inflammatory agent, and/or as an ingredient of functional foods. PMID:21981079

  19. Wedelolactone inhibits LPS-induced pro-inflammation via NF-kappaB Pathway in RAW 264.7 cells

    PubMed Central

    2013-01-01

    Background Wedelolactone (WEL), a major coumestan ingredient in Wedelia chinensis, has been used to treat septic shock, hepatitis and venom poisoning in traditional Chinese medicines. The objective of the study was to elucidate the anti-inflammatory effects and mechanism of WEL with a cellular model of lipopolysaccharide (LPS)-induced RAW 264.7 cells. Results To study the role of WEL in pro-inflammation, we measured key inflammation mediators and end products including nitric oxide (NO), prostaglandin E2 (PGE2), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and tumor necrosis factor-? (TNF-?) by using the Griess method, enzyme linked immunosorbent assay (ELISA) and Western blotting. Nuclear factor-kappaB (NF-?B) transcription activity was detected by luciferase reporter assay. The important pro-inflammatory transcription factors, NF-?B p65 and inhibitory kappaB alpha (I?B-?); and mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 MAPK (p38) were analyzed by Western blotting. Our study showed that WEL (0.1, 1, 10 ?M) significantly inhibited the protein expression levels of iNOS and COX-2 in LPS-stimulated cells, as well as the downstream products, including NO, PGE2 and TNF-?. Moreover, WEL also inhibited LPS-induced NF-?B p65 activation via the degradation and phosphorylation of I?B-? and subsequent translocation of the NF-?B p65 subunit to the nucleus. Conclusions Our results revealed that WEL has a potential to be a novel anti-inflammatory agent targeting on the NF-?B signaling pathway. PMID:24176090

  20. Manganese Potentiates LPS-Induced Heme-Oxygenase 1 in Microglia but not Dopaminergic Cells: Role in Controlling Microglial Hydrogen Peroxide and Inflammatory Cytokine Output

    PubMed Central

    Dodd, Celia A.; Filipov, Nikolay M.

    2012-01-01

    Excessive manganese (Mn) exposure increases output of glial-derived inflammatory products, which may indirectly contribute to the neurotoxic effects of this essential metal. In microglia, Mn increases hydrogen peroxide (H2O2) release and potentiates lipopolysaccharide (LPS)-induced cytokines (TNF-?, IL-6) and nitric oxide (NO). Inducible heme-oxygenase (HO-1) plays a role in the regulation of inflammation and its expression is upregulated in response to oxidative stressors, including metals and LPS. Because Mn can oxidatively affect neurons both directly and indirectly, we investigated the effect of Mn exposure on the induction of HO-1 in resting and LPS-activated microglia (N9) and dopaminergic neurons (N27). In microglia, 24 h exposure to Mn (up to 250 ?M) had minimal effects on its own, but it markedly potentiated LPS (100 ng/ml)-induced HO-1protein and mRNA. Inhibition of microglial HO-1 activity with two different inhibitors indicated that HO-1 is a positive regulator of the Mn-potentiated cytokine output and a negative regulator of the Mn-induced H2O2 output. Mn enhancement of LPS-induced HO-1 does not appear to be dependent on H2O2 or NO, as Mn+LPS-induced H2O2 release was not greater than the increase induced by Mn alone and inhibition of iNOS did not change Mn potentiation of HO-1. However, because Mn exposure potentiated the LPS-induced nuclear expression of small Maf proteins, this may be one mechanism Mn uses to affect the expression of HO-1 in activated microglia. Finally, the potentiating effects of Mn on HO-1 appear to be glia-specific for Mn, LPS, or Mn+LPS did not induce HO-1 in N27 neuronal cells. PMID:21963524

  1. Epoxyeicosatrienoic acids regulate macrophage polarization and prevent LPS-induced cardiac dysfunction.

    PubMed

    Dai, Meiyan; Wu, Lujin; He, Zuowen; Zhang, Shasha; Chen, Chen; Xu, Xizhen; Wang, Peihua; Gruzdev, Artiom; Zeldin, Darryl C; Wang, Dao Wen

    2015-09-01

    Macrophages, owning tremendous phenotypic plasticity and diverse functions, were becoming the target cells in various inflammatory, metabolic and immune diseases. Cytochrome P450 epoxygenase 2J2 (CYP2J2) metabolizes arachidonic acid to form epoxyeicosatrienoic acids (EETs), which possess various beneficial effects on cardiovascular system. In the present study, we evaluated the effects of EETs treatment on macrophage polarization and recombinant adeno-associated virus (rAAV)-mediated CYP2J2 expression on lipopolysaccharide (LPS)-induced cardiac dysfunction, and sought to investigate the underlying mechanisms. In vitro studies showed that EETs (1µmol/L) significantly inhibited LPS-induced M1 macrophage polarization and diminished the proinflammatory cytokines at transcriptional and post-transcriptional level; meanwhile it preserved M2 macrophage related molecules expression and upregulated anti-inflammatory cytokine IL-10. Furthermore, EETs down-regulated NF-?B activation and up-regulated peroxisome proliferator-activated receptors (PPAR?/?) and heme oxygenase 1 (HO-1) expression, which play important roles in regulating M1 and M2 polarization. In addition, LPS treatment in mice induced cardiac dysfunction, heart tissue damage and infiltration of M1 macrophages, as well as the increase of inflammatory cytokines in serum and heart tissue, but rAAV-mediated CYP2J2 expression increased EETs generation in heart and significantly attenuated the LPS-induced harmful effects, which mechanisms were similar as the in vitro study. Taken together, the results indicate that CYP2J2/EETs regulates macrophage polarization by attenuating NF-?B signaling pathway via PPAR?/? and HO-1 activation and its potential use in treatment of inflammatory diseases. J. Cell. Physiol. 230: 2108-2119, 2015. © 2015 Wiley Periodicals, Inc. PMID:25626689

  2. Effects of PPAR-? agonist treatment on LPS-induced mastitis in rats.

    PubMed

    Mingfeng, Ding; Xiaodong, Ming; Yue, Liu; Taikui, Piao; Lei, Xiao; Ming, Liu

    2014-12-01

    PPAR-?, a member of the nuclear receptor superfamily, plays an important role in lipid metabolism and inflammation. The aim of this study was to investigate the preventive effects of synthetic PPAR-? agonist rosiglitazone on lipopolysaccharide (LPS)-induced mastitis in rats. The mouse model of mastitis was induced by the injection of LPS through the duct of the mammary gland. Rosiglitazone was injected 1 h before the induction of LPS intraperitoneally. The results showed that rosiglitazone attenuated the infiltration of inflammatory cells, the activity of myeloperoxidase (MPO), and the production of tumor necrosis factor-? (TNF-?), interleukin-6 (IL-6), and interleukin-1? (IL-1?) in a dose-dependent manner. Additionally, Western blotting showed that rosiglitazone inhibited the phosphorylation of I?B-? and NF-?B p65. These results indicated that rosiglitazone has a protective effect on mastitis, and the anti-inflammatory mechanism of rosiglitazone on LPS-induced mastitis in rats may be due to its ability to inhibit NF-?B signaling pathways. PPAR-? may be a potential therapeutic target against mastitis. PMID:24839089

  3. Calorie restriction attenuates lipopolysaccharide (LPS)-induced microglial activation in discrete regions of the hypothalamus and the subfornical organ.

    PubMed

    Radler, Morgan E; Hale, Matthew W; Kent, Stephen

    2014-05-01

    Calorie restriction (CR) has been shown to increase longevity and elicit many health promoting benefits including delaying immunosenescence and attenuating neurodegeneration in animal models of Alzheimer's disease and Parkinson's disease. CR also suppresses microglial activation following cortical injury and aging. We previously demonstrated that CR attenuates lipopolysaccharide (LPS)-induced fever and shifts hypothalamic signaling pathways to an anti-inflammatory bias; however, the effects of CR on LPS-induced microglial activation remain largely unexplored. The current study investigated regional changes in LPS-induced microglial activation in mice exposed to 50% CR for 28days. Immunohistochemistry was conducted to examine changes in ionized calcium-binding adapter molecule-1 (Iba1), a protein constitutively expressed by microglia, in a total of 27 brain regions involved in immunity, stress, and/or thermoregulation. Exposure to CR attenuated LPS-induced fever, and LPS-induced microglial activation in a subset of regions: the arcuate nucleus (ARC) and ventromedial nucleus of the hypothalamus (VMH) and the subfornical organ (SFO). Microglial activation in the ARC and VMH was positively correlated with body temperature. These data suggest that CR exerts effects on regionally specific populations of microglia; particularly, in appetite-sensing regions of the hypothalamus, and/or regions lacking a complete blood brain barrier, possibly through altered pro- and anti-inflammatory signaling in these regions. PMID:24291211

  4. Dual Role of Lipopolysaccharide (LPS)Binding Protein in Neutralization of LPS and Enhancement of LPS-Induced Activation of Mononuclear Cells

    Microsoft Academic Search

    THOMAS GUTSMANN; MAREIKE MULLER; STEPHEN F. CARROLL; ROGER C. MACKENZIE; ANDRE WIESE; ULRICH SEYDEL

    2001-01-01

    The lipopolysaccharide (LPS)-binding protein (LBP) has a concentration-dependent dual role in the patho- genesis of gram-negative sepsis: low concentrations of LBP enhance the LPS-induced activation of mononu- clear cells (MNC), whereas the acute-phase rise in LBP concentrations inhibits LPS-induced cellular stimu- lation. In stimulation experiments, we have found that LBP mediates the LPS-induced cytokine release from MNC even under serum-free

  5. Moringa fruit inhibits LPS-induced NO/iNOS expression through suppressing the NF-? B activation in RAW264.7 cells.

    PubMed

    Lee, Hyo-Jin; Jeong, Yun-Jeong; Lee, Tae-Sung; Park, Yoon-Yub; Chae, Whi-Gun; Chung, Il-Kyung; Chang, Hyeun-Wook; Kim, Cheorl-Ho; Choi, Yung-Hyun; Kim, Wun-Jae; Moon, Sung-Kwon; Chang, Young-Chae

    2013-01-01

    In this study, we evaluated the anti-inflammatory effects of moringa (Moringa oleifera Lam.), a natural biologically active substance, by determining its inhibitory effects on pro-inflammatory mediators in lipopolysaccharide (LPS)-stimulated macrophage RAW264.7 cells. Extracts from different parts of moringa (root, leaf, and fruit) reduced LPS-induced nitric oxide (NO) release in a dose-dependent manner. The moringa fruit extract most effectively inhibited LPS-induced NO production and levels of inducible nitric oxide synthase (iNOS). The moringa fruit extract also was shown to suppress the production of inflammatory cytokines including IL-1?, TNF-?, and IL-6. Furthermore, moringa fruit extract inhibited the cytoplasmic degradation of I ? B -? and the nuclear translocation of p65 proteins, resulting in lower levels of NF -? B transactivation. Collectively, the results of this study demonstrate that moringa fruit extract reduces the levels of pro-inflammatory mediators including NO , IL-1?, TNF-?, and IL-6 via the inhibition of NF -? B activation in RAW264.7 cells. These findings reveal, in part, the molecular basis underlying the anti-inflammatory properties of moringa fruit extract. PMID:24117072

  6. LPS-Induced G-CSF Expression in Macrophages Is Mediated by ERK2, but Not ERK1

    PubMed Central

    Chang, Shwu-Fen; Lin, Shih-Shan; Yang, Hui-Ching; Chou, Yuan-Yi; Gao, Jhen-I; Lu, Shao-Chun

    2015-01-01

    Granulocyte colony-stimulating factor (G-CSF) selectively stimulates proliferation and differentiation of neutrophil progenitors which play important roles in host defense against infectious agents. However, persistent G-CSF production often leads to neutrophilia and excessive inflammatory reactions. There is therefore a need to understand the mechanism regulating G-CSF expression. In this study, we showed that U0126, a MEK1/2 inhibitor, decreases lipopolysaccharide (LPS)-stimulated G-CSF promoter activity, mRNA expression and protein secretion. Using short hairpin RNA knockdown, we demonstrated that ERK2, and not ERK1, involves in LPS-induced G-CSF expression, but not LPS-regulated expression of TNF-?. Reporter assays showed that ERK2 and C/EBP? synergistically activate G-CSF promoter activity. Further chromatin immunoprecipitation (ChIP) assays revealed that U0126 inhibits LPS-induced binding of NF-?B (p50/p65) and C/EBP? to the G-CSF promoter, but not their nuclear protein levels. Knockdown of ERK2 inhibits LPS-induced accessibility of the G-CSF promoter region to DNase I, suggesting that chromatin remodeling may occur. These findings clarify that ERK2, rather than ERK1, mediates LPS-induced G-CSF expression in macrophages by remodeling chromatin, and stimulates C/EBP?-dependent activation of the G-CSF promoter. This study provides a potential target for regulating G-CSF expression. PMID:26114754

  7. Leonurine ameliorates LPS-induced acute kidney injury via suppressing ROS-mediated NF-?B signaling pathway.

    PubMed

    Xu, Daliang; Chen, Maosheng; Ren, Xianzhi; Ren, Xianguo; Wu, Yonggui

    2014-09-01

    Acute kidney injury (AKI) is an abrupt loss of kidney function. Severe AKI requires renal replacement therapy and has high mortality. Leonurine (LEO), an alkaloid isolated from Leonurus cardiaca, has shown biological effects such as antioxidant, anticoagulant, and anti-apoptosis. We have examined the effect of LEO on lipopolysaccharide (LPS)-induced AKI in mice and further studied the mechanism involved. Blood urea nitrogen (BUN), creatinine and cytokine were estimated in the serum or tissue. Kidney tissue specimens were used for biochemical estimations of lipid peroxides (LPO), reduced glutathione (GSH), and reactive oxygen species (ROS). The effects of LEO on LPS-induced renal tissue damage were detected by hematoxylin and eosin (HE) stain and electron microscopy. The production of cytokines in the tissue and blood was measured by ELISA. Protein phosphorylation and protein subcellular localization were tested by Western blot. LEO is protected against LPS-induced AKI, improved animal survival and maintained the redox balance. The beneficial effects of LEO were accompanied by the down-regulation of TNF-?, IL-1, IL-6, IL-8, KIM-1 expression and by the inhibition of the phosphorylation of I?B? and p65 translocalization. These results suggest that LEO may suppress NF-?B activation and inhibit pro-inflammatory cytokine production via decreasing cellular ROS production. Accumulating studies have demonstrated that LEO reduces kidney injury and protects renal functions from LPS-induced kidney injury. PMID:24924288

  8. Necroptosis suppresses inflammation via termination of TNF- or LPS-induced cytokine and chemokine production.

    PubMed

    Kearney, C J; Cullen, S P; Tynan, G A; Henry, C M; Clancy, D; Lavelle, E C; Martin, S J

    2015-08-01

    TNF promotes a regulated form of necrosis, called necroptosis, upon inhibition of caspase activity in cells expressing RIPK3. Because necrosis is generally more pro-inflammatory than apoptosis, it is widely presumed that TNF-induced necroptosis may be detrimental in vivo due to excessive inflammation. However, because TNF is intrinsically highly pro-inflammatory, due to its ability to trigger the production of multiple cytokines and chemokines, rapid cell death via necroptosis may blunt rather than enhance TNF-induced inflammation. Here we show that TNF-induced necroptosis potently suppressed the production of multiple TNF-induced pro-inflammatory factors due to RIPK3-dependent cell death. Similarly, necroptosis also suppressed LPS-induced pro-inflammatory cytokine production. Consistent with these observations, supernatants from TNF-stimulated cells were more pro-inflammatory than those from TNF-induced necroptotic cells in vivo. Thus necroptosis attenuates TNF- and LPS-driven inflammation, which may benefit intracellular pathogens that evoke this mode of cell death by suppressing host immune responses. PMID:25613374

  9. In vivo morphine treatment synergistically increases LPS-induced caspase activity in immune organs

    PubMed Central

    Olin, Michael; Lee, Brian; Roy, Sabita; Molitor, Thomas

    2013-01-01

    Apoptosis is an important mechanism for the elimination of infected cells, which would normally serve as hosts for further pathogen replication. Apoptosis is initiated through complex pathways involving a family of cysteine proteases known as caspases. The detection of apoptosis is essential for understanding the long-term health effects inflicted by the therapeutic use of opiate drugs such as morphine for pain treatment following major trauma or disease and abusive use of such drugs in addiction. Common practices of apoptosis detection involve the removal of tissues, which subsequently induce spontaneous apoptosis unrelated to the actual effects of the opioid drug exposure. The objective of this study was to develop an in vivo detection method for assessing morphine’s ability to directly induce apoptosis, and in the combination of morphine following an inflammatory response induced by lipopolysaccharide (LPS). Mice were administered saline, morphine, LPS, or a combination of morphine and LPS. Prior to sacrifice, mice were injected with a poly-caspase-specific apoptosis detection probe, to detect internal caspase activity in vivo. Administration of morphine alone did not directly induce apoptosis. However, morphine significantly enhanced the LPS induced apoptosis in splenocyte and bone marrow cells as well as in spleen, liver, and thymus tissues. The use of a poly-caspase detection probe methodology, to label apoptotic cells in vivo, provides a powerful quantitative tool for the in vivo analysis of caspase activity. PMID:20390371

  10. p52-independent nuclear translocation of RelB promotes LPS-induced attachment

    SciTech Connect

    Saito, T. [Laboratory of Immunology, National Institute on Aging, NIH Biomedical Research Center, Baltimore, MD 21224 (United States)] [Laboratory of Immunology, National Institute on Aging, NIH Biomedical Research Center, Baltimore, MD 21224 (United States); Sasaki, C.Y., E-mail: sasakic@grc.nia.nih.gov [Laboratory of Immunology, National Institute on Aging, NIH Biomedical Research Center, Baltimore, MD 21224 (United States); Rezanka, L.J.; Ghosh, P.; Longo, D.L. [Laboratory of Immunology, National Institute on Aging, NIH Biomedical Research Center, Baltimore, MD 21224 (United States)] [Laboratory of Immunology, National Institute on Aging, NIH Biomedical Research Center, Baltimore, MD 21224 (United States)

    2010-01-01

    The NF-{kappa}B signaling pathways have a critical role in the development and progression of various cancers. In this study, we demonstrated that the small cell lung cancer cell line (SCLC) H69 expressed a unique NF-{kappa}B profile as compared to other cancer cell lines. The p105/p50, p100/p52, c-Rel, and RelB protein and mRNA transcripts were absent in H69 cells but these cells expressed RelA/p65. The activation of H69 cells by lipopolysaccharide (LPS) resulted in the induction of RelB and p100 expression. The treatment also induced the nuclear translocation of RelB without the processing of p100 to p52. Furthermore, LPS-induced {beta}1 integrin expression and cellular attachment through an NF-{kappa}B-dependent mechanism. Blocking RelB expression prevented the increase in the expression of {beta}1 integrin and the attachment of H69. Taken together, the results suggest that RelB was responsible for the LPS-mediated attachment and may play an important role in the progression of some cancers.

  11. Protection by LPS-induced inhibitory CD11b+ cells on corneal allograft

    PubMed Central

    Han, Yuping; Zhao, Shaozhen

    2015-01-01

    Objective: It is widely reported that CD11b+Gr1+ myeloid-derived suppressor cells can cause allograft tolerance in mice and human, however, little is known on the therapy role in chronic transplantation rejection. In this paper, their role in corneal transplantation was studied for the first time. Method: Inhibitory CD11b+ cells were obtained by murine LPS-induced septic model. Phenotype, endocytosis, antigen presenting ability, and T cell suppression assays were performed by flow cytometry analysis. The suppressive ability in vivo was analyzed by targeting allogeneic corneal transplantation. Results: LPS was intraperitoneally injected into C57BL/6 mice, the percentage of CD11b+ Gr1+ cells was increased in mice spleen, blood, and bone marrow, respectively. Compared with control mice, Ly6C, TLR2, and MHC-11 expression were higher in LPS treated mice. CD11b+ Gr1+ cells could inhibit allogenic corneal reaction in vivo after adoptive transfer, in consistent with an observation of inhibition effect on the antigen presenting cells (APCs) and CD4+ T cells proliferation in vitro. Conclusion: CD11b+ cells induced by LPS could function as inhibitory APCs, suppress CD4+ T cells proliferation and improve corneal allograft survival. Predictly, its application for cells transfer therapy in clinic in the further.

  12. Protective Effects of Baicalin on Decidua Cells of LPS-Induced Mice Abortion

    PubMed Central

    Wang, Xiaodan; Zhao, Yantao; Zhong, Xiuhui

    2014-01-01

    The study was carried out to investigate the protective effects of Baicalin on decidual cells of LPS-induced abortion mice. In the in vitro experiment, the decidual cells were cultured by uterus tissue mass cultivation sampled at day 6 of pregnancy, and gradient concentrations of LPS were used to determine the optimal LPS concentration of the injured decidual cells model. The injured decidual cells were treated with Baicalin (4??g/mL) to determine the protective role of Baicalin. In the in vivo experiment, lipopolysaccharide (LPS) was injected intravenously via the tail vein to induce abortion at day 6 of pregnancy, and the mice were given different concentrations of Baicalin by oral gavage consecutively at days 7 to 8 of pregnancy. On day 9 of gestation, the mice were sacrificed. The TNF and progesterone contents in the serum were assayed by ELISA. The results clearly revealed that Baicalin can prevent the injury to decidual cells from LPS dose dependently, TNF was decreased significantly (P < 0.01) compared to LPS group, and there was no effect on the progesterone. These findings suggest that Baicalin has protective effects on the injured decidual cells in the pregnant mice. PMID:25386564

  13. Granzyme K synergistically potentiates LPS-induced cytokine responses in human monocytes.

    PubMed

    Wensink, Annette C; Kemp, Vera; Fermie, Job; García Laorden, M Isabel; van der Poll, Tom; Hack, C Erik; Bovenschen, Niels

    2014-04-22

    Granzymes are serine proteases released by cytotoxic lymphocytes to induce apoptosis in virus-infected cells and tumor cells. Evidence is emerging that granzymes also play a role in controlling inflammation. Granzyme serum levels are elevated in patients with autoimmune diseases and infections, including sepsis. However, the function of extracellular granzymes in inflammation largely remains unknown. Here, we show that granzyme K (GrK) binds to Gram-negative bacteria and their cell-wall component lipopolysaccharide (LPS). GrK synergistically enhances LPS-induced cytokine release in vitro from primary human monocytes and in vivo in a mouse model of LPS challenge. Intriguingly, these extracellular effects are independent of GrK catalytic activity. GrK disaggregates LPS from micelles and augments LPS-CD14 complex formation, thereby likely boosting monocyte activation by LPS. We conclude that extracellular GrK is an unexpected direct modulator of LPS-TLR4 signaling during the antimicrobial innate immune response. PMID:24711407

  14. Involvement of mitogen-activated protein kinases and NF{kappa}B in LPS-induced CD40 expression on human monocytic cells

    SciTech Connect

    Wu Weidong [Center for Environmental Medicine, Asthma, and Lung Biology, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)]|[Department of Pediatrics, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)], E-mail: Weidong_Wu@med.unc.edu; Alexis, Neil E. [Center for Environmental Medicine, Asthma, and Lung Biology, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)]|[Department of Pediatrics, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Chen Xian [Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)]|[Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Bromberg, Philip A. [Center for Environmental Medicine, Asthma, and Lung Biology, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)]|[Department of Medicine, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Peden, David B. [Center for Environmental Medicine, Asthma, and Lung Biology, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)]|[Department of Pediatrics, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)]|[Department of Medicine, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)

    2008-04-15

    CD40 is a costimulatory molecule linking innate and adaptive immune responses to bacterial stimuli, as well as a critical regulator of functions of other costimulatory molecules. The mechanisms regulating lipopolysaccharide (LPS)-induced CD40 expression have not been adequately characterized in human monocytic cells. In this study we used a human monocytic cell line, THP-1, to investigate the possible mechanisms of CD40 expression following LPS exposure. Exposure to LPS resulted in a dose- and time-dependent increase in CD40 expression. Further studies using immunoblotting and pharmacological inhibitors revealed that mitogen-activated protein kinases (MAPKs) and NF{kappa}B were activated by LPS exposure and involved in LPS-induced CD40 expression. Activation of MAPKs was not responsible for LPS-induced NF{kappa}B activation. TLR4 was expressed on THP-1 cells and pretreatment of cells with a Toll-like receptor 4 (TLR4) neutralizing antibody (HTA125) significantly blunted LPS-induced MAPK and NF{kappa}B activation and ensuing CD40 expression. Additional studies with murine macrophages expressing wild type and mutated TLR4 showed that TLR4 was implicated in LPS-induced ERK and NF{kappa}B activation, and CD40 expression. Moreover, blockage of MAPK and NF{kappa}B activation inhibited LPS-induced TLR4 expression. In summary, LPS-induced CD40 expression in monocytic cells involves MAPKs and NF{kappa}B.

  15. A critical role for increased labile zinc in reducing sensitivity of cultured sheep pulmonary artery endothelial cells to LPS-induced apoptosis

    PubMed Central

    Thambiayya, Kalidasan; Wasserloos, Karla; Kagan, Valerian E.; Stoyanovsky, Detcho

    2012-01-01

    We previously noted an important signaling role for decreased labile intracellular zinc ([ Zn ] i) in LPS-induced apoptosis in cultured sheep pulmonary artery endothelial cells (SPAEC) (Tang ZL, Wasserloos KJ, Liu X, Stitt MS, Reynolds IJ, Pitt BR, St Croix CM. Mol Cell Biochem 234–235: 211–217, 2002; Thambiayya K, Wasserloos KJ, Huang Z, Kagan VE, St Croix CM, Pitt BR. Am J Physiol Lung Cell Mol Physiol 300: L624–632, 2011). In the present study, we used small interfering RNA (siRNA) to important contributors of zinc homeostasis [ SLC39A14 or Zrt/Irt-like protein 14 (ZIP14), a zinc importer; metallothionein (MT), a zinc binding protein ] to define molecular pathways by which extracellular zinc or nitric oxide (NO) increase labile [ Zn ] i [ e.g., zinc-sensitive fluorophore (FluoZin-3) detectable and/or chelatable by N,N,N?,N?-tetrakis(2-pyridylmethyl)ethylenediamine ] and reduce the sensitivity of SPAEC to LPS. Addition of 10 ?M zinc to serum-free medium of SPAEC increased [ Zn ] i and abolished LPS-induced apoptosis (e.g., increased annexin V binding). The increase in [ Zn ] i and the protective effect of extracellular zinc were sensitive to reduction in ZIP14 expression (by siRNA), but not affected by collectively knocking down major isoforms of sheep MT (sMT-Ia, -Ib, -Ic, and -II). Pretreatment of wild-type SPAEC with 250 ?M of the NO donor S-nitroso-N-acetylpenicillamine (SNAP) increased labile zinc in a relatively similar fashion to addition of extracellular zinc and reduced sensitivity of SPAEC to LPS-induced apoptosis (e.g., caspase-3/7 activation) in a N,N,N?,N?-tetrakis(2-pyridylmethyl)ethylenediamine-sensitive fashion. The antiapoptotic effects of SNAP were insensitive to siRNA knockdown of ZIP14, but were abolished (along with SNAP-induced increase in [ Zn ] i) when SPAEC were pretreated with siRNA to sheep MT. Zinc was able to directly inhibit recombinant caspase-3 activity in an in vitro assay. Collectively, these data show that increases in labile [ Zn ] i are an important component of ZIP14- or NO-mediated resistance to LPS-induced apoptosis. Cytoprotection via ZIP14 appeared to be secondary to transcellular movement of extracellular zinc, whereas NO-mediated protection was secondary to S-nitrosation of MT and redistribution of [ Zn ] i. PMID:22523284

  16. Attenuation of LPS-induced cyclooxygenase-2 and inducible NO synthase expression by lysophosphatidic acid in macrophages.

    PubMed

    Chien, Han-Yuan; Lu, Chih-Shen; Chuang, Kun-Han; Kao, Pu-Hong; Wu, Yuh-Lin

    2015-08-01

    LPS can activate the inflammatory cascades by inducing various inflammatory mediators, such as prostaglandin E2 (PGE2) resulting from cyclooxygenase-2 (COX-2), and NO produced by inducible NO synthase (iNOS). Lysophosphatidic acid (LPA) has been demonstrated to participate in inflammation. This study aimed to clarify the impact and the involving mechanisms of LPA on LPS-incurred inflammation in macrophages. First, LPA appeared to attenuate LPS-induced protein and mRNA expression of COX-2 and iNOS genes, as well as production of PGE2 and NO. By using selective inhibitors targeting various signaling players, the inhibitory G protein alpha subunit (G?i) seemed to be involved in the effect of LPA; p38, ERK and NF-?B were involved in the LPS-mediated COX-2/PGE2 pathway; and p38, JNK, phosphoinositide-3-kinase and NF-?B were involved in the LPS-mediated iNOS/NO pathway. LPA was able to diminish LPS-induced phosphorylation of p38 and Akt, as well as NF-?B p65 nuclear translocation. By utilization of inhibitors of COX-2 and iNOS, there appeared to be no modulation between the COX-2/PGE2 and the iNOS/NO signaling pathways. Our findings demonstrate a clear anti-inflammatory role of LPA acting via G?i in LPS-mediated inflammatory response in macrophages, owing, at least in part, to its suppressive effect on LPS-induced activation of p38, Akt and NF-?B. PMID:25783839

  17. Exogenous rhTRX reduces lipid accumulation under LPS-induced inflammation

    PubMed Central

    Han, Gi-Yeon; Lee, Eun-Kyung; Park, Hey-won; Kim, Hyun-Jung; Kim, Chan-Wha

    2014-01-01

    Redox-regulating molecule, recombinant human thioredoxin (rhTRX) which shows anti-inflammatory, and anti-oxidative effects against lipopolysaccharide (LPS)-stimulated inflammation and regulate protein expression levels. LPS-induced reactive oxygen intermediates (ROI) and NO production were inhibited by exogenous rhTRX. We identified up/downregulated intracellular proteins under the LPS-treated condition in exogenous rhTRX-treated A375 cells compared with non-LPS-treated cells via 2-DE proteomic analysis. Also, we quantitatively measured cytokines of in vivo mouse inflammation models using cytometry bead array. Exogenous rhTRX inhibited LPS-stimulated production of ROI and NO levels. TIP47 and ATP synthase may influence the inflammation-related lipid accumulation by affecting lipid metabolism. The modulation of skin redox environments during inflammation is most likely to prevent alterations in lipid metabolism through upregulation of TIP47 and ATP synthase and downregulation of inflammatory cytokines. Our results demonstrate that exogenous rhTRX has anti-inflammatory properties and intracellular regulatory activity in vivo and in vitro. Monitoring of LPS-stimulated pro-inflammatory conditions treated with rhTRX in A375 cells could be useful for diagnosis and follow-up of inflammation reduction related with candidate proteins. These results have a therapeutic role in skin inflammation therapy. PMID:24406320

  18. LPS-Induced Delayed Preconditioning Is Mediated by Hsp90 and Involves the Heat Shock Response in Mouse Kidney

    PubMed Central

    Kaucsár, Tamás; Bodor, Csaba; Godó, Mária; Szalay, Csaba; Révész, Csaba; Németh, Zalán; Mózes, Miklós; Szénási, Gábor; Rosivall, László; S?ti, Csaba; Hamar, Péter

    2014-01-01

    Introduction We and others demonstrated previously that preconditioning with endotoxin (LPS) protected from a subsequent lethal LPS challenge or from renal ischemia-reperfusion injury (IRI). LPS is effective in evoking the heat shock response, an ancient and essential cellular defense mechanism, which plays a role in resistance to, and recovery from diseases. Here, by using the pharmacological Hsp90 inhibitor novobiocin (NB), we investigated the role of Hsp90 and the heat shock response in LPS-induced delayed renal preconditioning. Methods Male C57BL/6 mice were treated with preconditioning (P: 2 mg/kg, ip.) and subsequent lethal (L: 10 mg/kg, ip.) doses of LPS alone or in combination with NB (100 mg/kg, ip.). Controls received saline (C) or NB. Results Preconditioning LPS conferred protection from a subsequent lethal LPS treatment. Importantly, the protective effect of LPS preconditioning was completely abolished by a concomitant treatment with NB. LPS induced a marked heat shock protein increase as demonstrated by Western blots of Hsp70 and Hsp90. NB alone also stimulated Hsp70 and Hsp90 mRNA but not protein expression. However, Hsp70 and Hsp90 protein induction in LPS-treated mice was abolished by a concomitant NB treatment, demonstrating a NB-induced impairment of the heat shock response to LPS preconditioning. Conclusion LPS-induced heat shock protein induction and tolerance to a subsequent lethal LPS treatment was prevented by the Hsp90 inhibitor, novobiocin. Our findings demonstrate a critical role of Hsp90 in LPS signaling, and a potential involvement of the heat shock response in LPS-induced preconditioning. PMID:24646925

  19. Effect of azithromycin on the LPS-induced production and secretion of phospholipase A2 in lung cells.

    PubMed

    Kitsiouli, Eirini; Antoniou, Georgia; Gotzou, Helen; Karagiannopoulos, Michalis; Basagiannis, Dimitris; Christoforidis, Savvas; Nakos, George; Lekka, Marilena E

    2015-07-01

    Azithromycin is a member of macrolides, utilized in the treatment of infections. Independently, these antibiotics also possess anti-inflammatory and immunomodulatory properties. Phospholipase A2 isotypes, which are implicated in the pathophysiology of inflammatory lung disorders, are produced by alveolar macrophages and other lung cells during inflammatory response and can promote lung injury by destructing lung surfactant. The aim of the study was to investigate whether in lung cells azithromycin can inhibit secretory and cytosolic phospholipases A2, (sPLA2) and (cPLA2), respectively, which are induced by an inflammatory trigger. In this respect, we studied the lipopolysaccharide (LPS)-mediated production or secretion of sPLA2 and cPLA2 from A549 cells, a cancer bronchial epithelial cell line, and alveolar macrophages, isolated from bronchoalveolar lavage fluid of ARDS and control patients without cardiopulmonary disease or sepsis. Pre-treatment of cells with azithromycin caused a dose-dependent decrease in the LPS-induced sPLA2-IIA levels in A549 cells. This inhibition was rather due to reduced PLA2G2A mRNA expression and secretion of sPLA2-IIA protein levels, as observed by western blotting and indirect immunofluorescence by confocal microscopy, respectively, than to the inhibition of the enzymic activity per se. On the contrary, azithromycin had no effect on the LPS-induced production or secretion of sPLA2-IIA from alveolar macrophages. The levels of LPS-induced c-PLA2 were not significantly affected by azithromycin in either cell type. We conclude that azithromycin exerts anti-inflammatory properties on lung epithelial cells through the inhibition of both the expression and secretion of LPS-induced sPLA2-IIA, while it does not affect alveolar macrophages. PMID:25791017

  20. EPA and DHA reduce LPS-induced inflammation responses in HK-2 cells: Evidence for a PPAR-?–dependent mechanism

    Microsoft Academic Search

    HANG LI; Xiong Z. Ruan; Stephen H. Powis; RAY FERNANDO; Wint Y. Mon; David C. Wheeler; John F. Moorhead; ZAC VARGHESE

    2005-01-01

    EPA and DHA reduce LPS-induced inflammation responses in HK-2 cells: Evidence for a PPAR-?–dependent mechanism.BackgroundRecent studies have shown that fish oil, containing ?-3 polyunsaturated fatty acids (?-3 PUFAs) eicosapentaenoic acid (EPA) (C20:5 ? 3), and docosahexaenoic acid (DHA) (C22:6 ? 3) retard the progression of renal disease, especially in IgA nephropathy (IgAN). Despite increasing knowledge of the beneficial effects of

  1. Flurbiprofen Enantiomers Inhibit Inducible Nitric Oxide Synthase Expression in RAW 264.7 Macrophages

    Microsoft Academic Search

    Burkhard Hinz; Kay Brune; Thomas Rau; Andreas Pahl

    2001-01-01

    Purpose. Using RAW 264.7 macrophages, the present study investigates the influence of optically pure enantiomers of the nonsteroidal anti-inflammatory drug flurbiprofen on lipopolysaccharide (LPS)-induced inducible nitric oxide synthase (iNOS) expression.

  2. Tanshinone IIA therapeutically reduces LPS-induced acute lung injury by inhibiting inflammation and apoptosis in mice

    PubMed Central

    Xu, Min; Cao, Fa-le; Zhang, Yu-fei; Shan, Liang; Jiang, Xiao-ling; An, Xiao-jing; Xu, Wei; Liu, Xiu-zhi; Wang, Xiao-yan

    2015-01-01

    Aim: To study the effects of tanshinone IIA (TIIA) on lipopolysaccharide (LPS)-induced acute lung injury in mice and the underlying mechanisms. Methods: Mice were injected with LPS (10 mg/kg, ip), then treated with TIIA (10 mg/kg, ip). Seven hours after LPS injection, the lungs were collected for histological study. Protein, LDH, TNF-? and IL-1? levels in bronchoalveolar lavage fluid (BALF) and myeloperoxidase (MPO) activity in lungs were measured. Cell apoptosis and Bcl-2, caspase-3, NF-?B and HIF-1? expression in lungs were assayed. Results: LPS caused marked histological changes in lungs, accompanied by significantly increased lung W/D ratio, protein content and LDH level in BALF, and Evans blue leakage. LPS markedly increased neutrophil infiltration in lungs and inflammatory cytokines in BALF. Furthermore, LPS induced cell apoptosis in lungs, as evidenced by increased TUNEL-positive cells, decreased Bcl-2 content and increased cleaved caspase-3 content. Moreover, LPS significantly increased the expression of NF-?B and HIF-1? in lungs. Treatment of LPS-injected mice with TIIA significantly alleviated these pathological changes in lungs. Conclusion: TIIA alleviates LPS-induced acute lung injury in mice by suppressing inflammatory responses and apoptosis, which is mediated via inhibition of the NF-?B and HIF-1? pathways. PMID:25544360

  3. The Fusarium toxin deoxynivalenol (DON) modulates the LPS induced acute phase reaction in pigs.

    PubMed

    Dänicke, Sven; Brosig, Bianca; Kersten, Susanne; Kluess, Jeannette; Kahlert, Stefan; Panther, Patricia; Diesing, Anne-Kathrin; Rothkötter, Hermann-Josef

    2013-07-01

    The systemic effects of the Fusarium toxin deoxynivalenol (DON) and of bacterial lipopolysaccharides (LPS) were studied in male castrated pigs (40.4 ± 3.7 kg) infused intravenously with either DON or LPS alone (100 ?g DON/kg/h, 7.5 ?g/LPS/kg/h), or together (100 ?g DON plus 7.5 ?g/LPS/kg/h). The Control group received a saline infusion (n=6/treatment, 24h observation period). An additional DON infusion did not exacerbate the clinical signs observed in LPS-infused pigs. For example, rectal temperature climaxed after 4h (40.4 ± 0.2°C) and 5h (40.1 ± 0.3°C), in the LPS and LPS+DON group, respectively. Saline and DON alone did not induce an acute phase reaction as indicated by unaltered plasma levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) while LPS caused a significant rise of both cytokines. TNF-alpha plasma peak concentrations were significantly higher in the LPS compared to the DON+LPS group (94.3 ± 17.2 ng/mL vs. 79.2 ± 15.7 ng/mL) while IL-6 climaxed earlier in the latter group (3h p.i. vs. 2h p.i.). From the tested clinical-chemical plasma characteristics the total bilirubin concentration and the ASAT activity were strongly elevated by the LPS infusion and additionally increased and decreased by DON, respectively. In conclusion, the LPS-induced effects were only marginally modified by DON. PMID:23603058

  4. Tyrosine kinase inhibitor tyrphostin AG490 reduces liver injury in LPS-induced shock.

    PubMed

    Gyurkovska, Valeriya; Ivanovska, Nina

    2015-03-15

    Sepsis remains a serious clinical problem despite continuous efforts to increase survival. Experimental animal models of sepsis are pointed to a great extent on blocking the activity of cytokines. A number of signal-transducing molecules are associated with the occurrence of excessive tissue inflammation. Through inhibition of tyrosine phosphorilation and thereby changing cell signaling, tyrosine kinase inhibitors can influence multiple inflammatory pathways. The purpose of the present investigation was to evaluate the effect of tyrosine kinase inhibitor tyrphostin AG490 in a mouse LPS-induced shock. Cytokine and chemokine blood levels were determined by ELISA assays. CD11b(+) Ly6C(+), CD3(+)CD69(+) and C5aR positive cell populations in the peritoneal exudate were detected by flow cytometry. The expression of iNOS and Signal Transducer and Activator of Transcription (STAT) in the liver were observed by immunohistochemistry. We found that tyrphostin AG490 inhibited Regulated upon activation normal T cell expressed and secreted (RANTES), IL-6 and IL-12 serum levels, decreased the number of CD11b(+)Ly6C(+) and CD3(+)CD69(+) subpopulations in the peritoneal exudate and prevented the decrease of cells expressing C5a receptor and TNF-alpha receptor. Tyrphostin ameliorated liver injury associated with suppressed iNOS, STAT3 and pSTAT3 expression. Our data suggest that tyrphostin AG490 diminished the degree of inflammation starting in peritoneal cavity and minimized liver dysfunction thus representing one approach for better outcome of sepsis conditions. PMID:25666385

  5. Icariin attenuates LPS-induced acute inflammatory responses: Involvement of PI3K\\/Akt and NF-?B signaling pathway

    Microsoft Academic Search

    Chang-Qing Xu; Bao-Jun Liu; Jin-Feng Wu; Yan-Chun Xu; Xiao-Hong Duan; Yu-Xue Cao; Jing-Cheng Dong

    2010-01-01

    This study aimed to investigate the mechanism underlying the attenuation of LPS-induced lung inflammation by icariin in vivo and in vitro. The anti-inflammatory effects of icariin on LPS-induced acute inflammatory and the molecular mechanism were investigated. Pretreatment with icarrin (20mg\\/kg) could attenuate acute lung inflammation by inhibiting mRNA expressions of tumor necrosis factor alpha (TNF-?), interleukin-6 (IL-6), metalloproteinase cycloxygenase-2 (COX-2),

  6. Effects of peroxisome proliferator-activated receptor agonists on LPS-induced neuronal death in mixed cortical neurons: associated with iNOS and COX2

    Microsoft Academic Search

    Eun Joo Kim; Kyoung Ja Kwon; Jee-Young Park; Soo Hwan Lee; Chang-Hyun Moon; Eun Joo Baik

    2002-01-01

    In neurodegenerative disease, the use of non-steroidal anti-inflammatory drugs (NSAIDs) has been regarded as beneficial. The NSAID, an inhibitor of cyclooxygenase (COX), has been also suggested as a ligand of the peroxisome proliferator-activated receptor (PPAR). In cortical neuron–glial co-cultures, we examined the effect of PPAR agonists on lipopolysaccharide(LPS)-induced neuronal death, which has been known to be NO-dependent. LPS induced iNOS

  7. Spirulina Promotes Stem Cell Genesis and Protects against LPS Induced Declines in Neural Stem Cell Proliferation

    PubMed Central

    Bachstetter, Adam D.; Jernberg, Jennifer; Schlunk, Andrea; Vila, Jennifer L.; Hudson, Charles; Cole, Michael J.; Shytle, R. Douglas; Tan, Jun; Sanberg, Paul R.; Sanberg, Cyndy D.; Borlongan, Cesario; Kaneko, Yuji; Tajiri, Naoki; Gemma, Carmelina; Bickford, Paula C.

    2010-01-01

    Adult stem cells are present in many tissues including, skin, muscle, adipose, bone marrow, and in the brain. Neuroinflammation has been shown to be a potent negative regulator of stem cell and progenitor cell proliferation in the neurogenic regions of the brain. Recently we demonstrated that decreasing a key neuroinflammatory cytokine IL-1? in the hippocampus of aged rats reversed the age-related cognitive decline and increased neurogenesis in the age rats. We also have found that nutraceuticals have the potential to reduce neuroinflammation, and decrease oxidative stress. The objectives of this study were to determine if spirulina could protect the proliferative potential of hippocampal neural progenitor cells from an acute systemic inflammatory insult of lipopolysaccharide (LPS). To this end, young rats were fed for 30 days a control diet or a diet supplemented with 0.1% spirulina. On day 28 the rats were given a single i.p. injection of LPS (1 mg/kg). The following day the rats were injected with BrdU (50 mg/kg b.i.d. i.p.) and were sacrificed 24 hours after the first injection of BrdU. Quantification of the BrdU positive cells in the subgranular zone of the dentate gyrus demonstrated a decrease in proliferation of the stem/progenitor cells in the hippocampus as a result of the LPS insult. Furthermore, the diet supplemented with spirulina was able to negate the LPS induced decrease in stem/progenitor cell proliferation. In a second set of studies we examined the effects of spirulina either alone or in combination with a proprietary formulation (NT-020) of blueberry, green tea, vitamin D3 and carnosine on the function of bone marrow and CD34+ cells in vitro. Spirulina had small effects on its own and more than additive effects in combination with NT-020 to promote mitochondrial respiration and/or proliferation of these cells in culture. When examined on neural stem cells in culture spirulina increased proliferation at baseline and protected against the negative influence of TNF? to reduce neural stem cell proliferation. These results support the hypothesis that a diet enriched with spirulina and other nutraceuticals may help protect the stem/progenitor cells from insults. PMID:20463965

  8. Involvement of TNF alpha, IL-1 beta and IL-1 receptor antagonist in LPS-induced rabbit uveitis.

    PubMed

    Mo, J S; Matsukawa, A; Ohkawara, S; Yoshinaga, M

    1998-05-01

    The objective of the study was to investigate involvement of TNF alpha, IL-1 beta and IL-1 receptor antagonist (IL-1Ra) in lipopolysaccharide (LPS)-induced uveitis. Intravitreal injection of LPS (100 ng) to rabbits induced a massive leukocyte infiltration and protein leakage into the aqueous humor. Aqueous leukocyte counts and protein levels reached a peak 24 hr after this injection. The peak concentrations of aqueous TNF alpha (230 +/- 37 pg ml-1, at 9 hr) and IL-1 beta (185 +/- 80 pg ml-1, at 18 hr) preceded peak levels of aqueous leukocyte counts and protein levels. In contrast, the levels of aqueous IL-1Ra peaked at 48 hr (12,239 +/- 1964 pg ml-1) and a fairly high concentration of IL-1Ra remained when the inflammatory reactions subsided. Immunohistochemistry and leukocyte-depletion studies showed that infiltrating leukocytes were the major cellular sources of aqueous TNF alpha, IL-1 beta and IL-1Ra. Intravitreal injection of homologous TNF alpha (0.1-1.5 micrograms) or IL-1 beta (0.5-5 ng) reproduced a rapid leukocyte infiltration and protein leakage. Administration of anti-TNF alpha mAb (10 micrograms) suppressed the number of LPS-induced infiltrating neutrophils by 50%, mononuclear cells by 58%, and protein leakage by 42%. Administration of rabbit IL-1Ra (10 micrograms) also suppressed neutrophil influx by 78%, however, neither mononuclear cell influx nor protein leakage was inhibited by rabbit IL-1Ra. Co-administration of the two inhibitors enhanced inhibition of neutrophil infiltration to 88%, and protein leakage to 64%. We conclude that TNF alpha and IL-1 beta are the principal mediators of LPS-induced uveitis. Our observations also suggest that endogenous IL-1Ra may down-regulate inflammatory reactions. PMID:9628802

  9. Cobalt protoporphyrin accelerates TFEB activation and lysosome reformation during LPS-induced septic insults in the rat heart.

    PubMed

    Unuma, Kana; Aki, Toshihiko; Funakoshi, Takeshi; Yoshida, Ken-ichi; Uemura, Koichi

    2013-01-01

    Lipopolysaccharide (LPS)-induced myocardial dysfunction is caused, at least in part, by mitochondrial dysfunction. Mitochondrial dysfunction and the oxidative damage associated with it are scavenged through various cellular defense systems such as autophagy to prevent harmful effects. Our recent study has demonstrated that cobalt protoporphyrin IX (CoPPIX), a potent inducer of heme oxygenase-1 (HO-1), ameliorates septic liver injuries by enhancing mitochondrial autophagy in rats. In our current study, we show that CoPPIX (5 mg/kg s.c.) not only accelerates the autophagic response but also promotes lysosome reformation in the rat heart treated with LPS (15 mg/kg i.p.). Lysosomal membrane-associated protein-2 (LAMP2), which is essential to the maintenance of lysosomal functions in the heart, is depleted transiently but restored rapidly during LPS administration in the rat. Activation of transcription factor EB (TFEB), a master regulator of lysosomal biogenesis and autophagy, was also observed, indicating a hyper consumption and subsequent reformation of the lysosome to meet the increased demand for autophagosome cleaning. CoPPIX was found to promote these processes and tended to restore the LPS-induced suppression of cardiac performances whilst chloroquine (CQ; 20 mg/kg i.p.), an inhibitor of lysosomes and autophagic protein degradation, abrogates these beneficial effects. The cardioprotective effect of CoPPIX against LPS toxicity was also observed via decreased levels of cardiac releasing enzymes in the plasma. Taken together, our current data indicate that lysosome reformation mediated by TFEB may be involved in cardioprotection against LPS-induced septic insults, and serve as a novel mechanism by which CoPPIX protects the heart against oxidative stress. PMID:23457579

  10. Cobalt Protoporphyrin Accelerates TFEB Activation and Lysosome Reformation during LPS-Induced Septic Insults in the Rat Heart

    PubMed Central

    Unuma, Kana; Aki, Toshihiko; Funakoshi, Takeshi; Yoshida, Ken-ichi; Uemura, Koichi

    2013-01-01

    Lipopolysaccharide (LPS)-induced myocardial dysfunction is caused, at least in part, by mitochondrial dysfunction. Mitochondrial dysfunction and the oxidative damage associated with it are scavenged through various cellular defense systems such as autophagy to prevent harmful effects. Our recent study has demonstrated that cobalt protoporphyrin IX (CoPPIX), a potent inducer of heme oxygenase-1 (HO-1), ameliorates septic liver injuries by enhancing mitochondrial autophagy in rats. In our current study, we show that CoPPIX (5 mg/kg s.c.) not only accelerates the autophagic response but also promotes lysosome reformation in the rat heart treated with LPS (15 mg/kg i.p.). Lysosomal membrane-associated protein-2 (LAMP2), which is essential to the maintenance of lysosomal functions in the heart, is depleted transiently but restored rapidly during LPS administration in the rat. Activation of transcription factor EB (TFEB), a master regulator of lysosomal biogenesis and autophagy, was also observed, indicating a hyper consumption and subsequent reformation of the lysosome to meet the increased demand for autophagosome cleaning. CoPPIX was found to promote these processes and tended to restore the LPS-induced suppression of cardiac performances whilst chloroquine (CQ; 20 mg/kg i.p.), an inhibitor of lysosomes and autophagic protein degradation, abrogates these beneficial effects. The cardioprotective effect of CoPPIX against LPS toxicity was also observed via decreased levels of cardiac releasing enzymes in the plasma. Taken together, our current data indicate that lysosome reformation mediated by TFEB may be involved in cardioprotection against LPS-induced septic insults, and serve as a novel mechanism by which CoPPIX protects the heart against oxidative stress. PMID:23457579

  11. Heat Shock Protein 90 Inhibitors Prevent LPS-Induced Endothelial Barrier Dysfunction by Disrupting RhoA Signaling

    PubMed Central

    Joshi, Atul D.; Dimitropoulou, Christiana; Thangjam, Gagan; Snead, Connie; Feldman, Sara; Barabutis, Nektarios; Fulton, David; Hou, Yali; Kumar, Sanjiv; Patel, Vijay; Gorshkov, Boris; Verin, Alexander D.; Black, Stephen M.

    2014-01-01

    Permeability of the endothelial monolayer is increased when exposed to the bacterial endotoxin LPS. Our previous studies have shown that heat shock protein (Hsp) 90 inhibitors protect and restore LPS-mediated hyperpermeability in bovine pulmonary arterial endothelial cells. In this study, we assessed the effect of Hsp90 inhibition against LPS-mediated hyperpermeability in cultured human lung microvascular endothelial cells (HLMVECs) and delineated the underlying molecular mechanisms. We demonstrate that Hsp90 inhibition is critical in the early phase, to prevent LPS-mediated hyperpermeability, and also in the later phase, to restore LPS-mediated hyperpermeability in HLMVECs. Because RhoA is a well known mediator of endothelial hyperpermeability, we investigated the effect of Hsp90 inhibition on LPS-mediated RhoA signaling. RhoA nitration and activity were increased by LPS in HLMVECs and suppressed when pretreated with the Hsp90 inhibitor, 17-allylamino-17 demethoxy-geldanamycin (17-AAG). In addition, inhibition of Rho kinase, a downstream effector of RhoA, protected HLMVECs from LPS-mediated hyperpermeability and abolished LPS-induced myosin light chain (MLC) phosphorylation, a target of Rho kinase. In agreement with these findings, 17-AAG or dominant-negative RhoA attenuated LPS-induced MLC phosphorylation. MLC phosphorylation induced by constitutively active RhoA was also suppressed by 17-AAG, suggesting a role for Hsp90 downstream of RhoA. Inhibition of Src family kinases also suppressed RhoA activity and MLC phosphorylation. Together, these data indicate that Hsp90 inhibition prevents and repairs LPS-induced lung endothelial barrier dysfunction by suppressing Src-mediated RhoA activity and signaling. PMID:23972231

  12. The pore-forming subunit of the KATP channel is an important molecular target for LPS-induced vascular hyporeactivity in vitro

    PubMed Central

    O'Brien, Alastair J; Thakur, Gita; Buckley, James F; Singer, Mervyn; Clapp, Lucie H

    2005-01-01

    ATP-sensitive K+ (KATP) channel activation is implicated in the vascular hyporeactivity occurring in septic shock. However, channel inhibition with the sulphonylurea receptor (SUR) antagonist, glibenclamide (Glib) fails to reverse lipopolysaccharide (LPS)-induced vascular hyporeactivity in vitro. We investigated whether inhibitors that act by binding to the KATP channel pore could be effective. Ring segments of endothelium-intact rat mesenteric artery were incubated with LPS in culture media for either 6 or 20?h before contractile responses to phenylephrine were assessed in the absence or presence of KATP channel inhibitors. The pore-forming subunit inhibitors barium chloride (BaCl2; 300??M) and PNU-37883A (1??M) significantly reversed hyporeactivity at both time points, although less so at 20?h. In contrast, the SUR inhibitors, Glib (10??M), tolbutamide (Tolb) (1?mM) and PNU-99963 (1??M) were ineffective. In LPS-incubated tissues, Glib and Tolb antagonised contractions to the thromboxane A2 mimetic, U46619 (9,11-dideoxy-9?, 11?-methanoepoxy prostaglandin F2?) (10?7?M), whereas the pinacidil-derived inhibitor, PNU-99963, did not. Contractions to 60?mM KCl were unaffected by LPS at 6?h, but were significantly depressed by LPS at 20?h, suggesting that K+-channel-independent pathways contribute to hyporeactivity at the later time point. The inducible nitric oxide synthase (iNOS) inhibitor, 1400?W (10??M) and Tolb inhibited the production of nitrite induced by LPS, whereas BaCl2 and PNU-37883A had no effect. In conclusion, KATP channels contribute to LPS-induced vascular hyporeactivity via the iNOS pathway in rat mesenteric artery. The effectiveness of pore inhibitors over SUR inhibitors of the KATP channel suggests altered SUR function following LPS administration, which cannot be explained by thromboxane receptor inhibition. PMID:15655519

  13. Low level laser therapy reduces acute lung inflammation in a model of pulmonary and extrapulmonary LPS-induced ARDS.

    PubMed

    Oliveira, Manoel Carneiro; Greiffo, Flávia Regina; Rigonato-Oliveira, Nicole Cristine; Custódio, Ricardo Wesley Alberca; Silva, Vanessa Roza; Damaceno-Rodrigues, Nilsa Regina; Almeida, Francine Maria; Albertini, Regiane; Lopes-Martins, Rodrigo Álvaro B; de Oliveira, Luis Vicente Franco; de Carvalho, Paulo de Tarso Camillo; Ligeiro de Oliveira, Ana Paula; Leal Jr, Ernesto César P; Vieira, Rodolfo P

    2014-05-01

    The present study aimed to investigate the effects low level laser therapy (LLLT) in a LPS-induced pulmonary and extrapulmonary acute respiratory distress syndrome (ARDS) in BALB/c mice. Laser (830nm laser, 9J/cm(2), 35mW, 80s per point, 3 points per application) was applied in direct contact with skin, 1h after LPS administration. Mice were distributed in control (n=6; PBS), ARDS IT (n=7; LPS orotracheally 10?g/mouse), ARDS IP (n=7; LPS intra-peritoneally 100?g/mouse), ARDS IT+Laser (n=9; LPS intra-tracheally 10?g/mouse), ARDS IP+Laser (n=9; LPS intra-peritoneally 100?g/mouse). Twenty-four hours after last LPS administration, mice were studied for pulmonary inflammation by total and differential cell count in bronchoalveolar lavage (BAL), cytokines (IL-1beta, IL-6, KC and TNF-alpha) levels in BAL fluid and also by quantitative analysis of neutrophils number in the lung parenchyma. LLLT significantly reduced pulmonary and extrapulmonary inflammation in LPS-induced ARDS, as demonstrated by reduced number of total cells (p<0.001) and neutrophils (p<0.001) in BAL, reduced levels of IL-1beta, IL-6, KC and TNF-alpha in BAL fluid and in serum (p<0.001), as well as the number of neutrophils in lung parenchyma (p<0.001). LLLT is effective to reduce pulmonary inflammation in both pulmonary and extrapulmonary model of LPS-induced ARDS. PMID:24792475

  14. Anti-inflammatory activity of cinnamon water extract in vivo and in vitro LPS-induced models

    PubMed Central

    2012-01-01

    Background Cinnamon bark is one of the most popular herbal ingredients in traditional oriental medicine and possesses diverse pharmacological activities including anti-bacterial, anti-viral, and anti-cancer properties. The goal of this study is to investigate the in vivo and in vitro inhibitory effect of cinnamon water extract (CWE) on lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF)-? and its underlying intracellular mechanisms. Methods CWE was orally administrated to mice for 6 days prior to intraperitoneal injection of LPS. Serum levels of TNF-? and interleukin (IL)-6 were determined 1 hour after LPS stimulation. Peritoneal macrophages from thioglycollate-injected mice were isolated and assayed for viability, cytokine expression and signaling molecules upon LPS stimulation. CWE was further fractioned according to molecular size, and the levels of total polyphenols and biological activities of each fraction were measured. Results The oral administration of CWE to mice significantly decreased the serum levels of TNF-? and IL-6. CWE treatment in vitro decreased the mRNA expression of TNF-?. CWE blocked the LPS-induced degradation of I?B? as well as the activation of JNK, p38 and ERK1/2. Furthermore, size-based fractionation of CWE showed that the observed inhibitory effect of CWE in vitro occurred in the fraction containing the highest level of total polyphenols. Conclusions Treatment with CWE decreased LPS-induced TNF-? in serum. In vitro inhibition of TNF-? gene by CWE may occur via the modulation of I?B? degradation and JNK, p38, and ERK1/2 activation. Our results also indicate that the observed anti-inflammatory action of CWE may originate from the presence of polyphenols. PMID:23190501

  15. Whole-body deletion of LPS-induced TNF-? factor (LITAF) markedly improves experimental endotoxic shock and inflammatory arthritis

    PubMed Central

    Merrill, Jamie C.; You, Jian; Constable, Cara; Leeman, Susan E.; Amar, Salomon

    2011-01-01

    LPS-induced TNF-? factor (LITAF) mediates cytokine expression in response to endotoxin challenge. Previously, we reported that macrophage-specific LITAF-deficient (macLITAF?/?) mice exposed to LPS have a delayed onset in the serum levels of proinflammatory cytokines and prolonged persistence of anti-inflammatory cytokines, but only partial protection from endotoxic shock. We postulated that greater protection might be achieved if LITAF were deleted from all LITAF-producing cells, including macrophages. Using a Cre-loxP system, we engineered a tamoxifen-induced recombination mouse [tamLITAF(i)?/?] that resulted in whole-body LITAF deficiency. Our findings demonstrate that (i) tamLITAF(i)?/? mice are more resistant to systemic Escherichia coli LPS-induced lethality than our previous macLITAF?/? mice, providing evidence that LITAF-producing cells other than LysMCre-positive cells play an important role in mediating endotoxic shock; (ii) tamLITAF(i)?/? mice show a similar pattern of cytokine expression with decreased proinflammatory and prolonged anti-inflammatory mediators compared with WT mice; and (iii) tamLITAF(i)?/? mice, compared with WT mice, display a significant reduction in bone resorption and inflammation associated with a local chronic inflammatory disease—namely, collagen antibody-induced arthritis. Our findings offer a unique model to study the role of LITAF in systemic and chronic local inflammatory processes, and pave the way for anti-LITAF therapeutic approaches for the treatment of TNF-mediated inflammatory diseases. PMID:22160695

  16. Antinociceptive Effect of Tetrandrine on LPS-Induced Hyperalgesia via the Inhibition of IKK? Phosphorylation and the COX-2/PGE2 Pathway in Mice

    PubMed Central

    Zhao, Hengguang; Luo, Fuling; Li, Hongzhong; Zhang, Li; Yi, Yongfen; Wan, Jingyuan

    2014-01-01

    Tetrandrine (TET) is a bisbenzylisoquinoline alkaloid that is isolated from the Stephania Tetrandra. It is known to possess anti-inflammatory and immunomodulatory effects. We have shown that TET can effectively suppress the production of bacterial lipopolysaccharide (LPS)-induced inflammatory mediators, including cyclooxygenases (COXs), in macrophages. However, whether TET has an antinociceptive effect on LPS-induced hyperalgesia is unknown. In the present study, we investigated the potential antinociceptive effects of TET and the mechanisms by which it elicits its effects on LPS-induced hyperalgesia. LPS effectively evoked hyperalgesia and induced the production of PGE2 in the sera, brain tissues, and cultured astroglia. TET pretreatment attenuated all of these effects. LPS also activated inhibitor of ?B (I?B) kinase ? (IKK?) and its downstream components in the I?B/nuclear factor (NF)-?B signaling pathway, including COX-2; the increase in expression levels of these components was significantly abolished by TET. Furthermore, in primary astroglia, knockdown of IKK?, but not IKK?, reversed the effects of TET on the LPS-induced increase in I?B phosphorylation, P65 phosphorylation, and COX-2. Our results suggest that TET can effectively exert antinociceptive effects on LPS-induced hyperalgesia in mice by inhibiting IKK? phosphorylation, which leads to the reduction in the production of important pain mediators, such as PGE2 and COX-2, via the IKK?/I?B/NF-?B pathway. PMID:24722146

  17. Antinociceptive effect of tetrandrine on LPS-induced hyperalgesia via the inhibition of IKK? phosphorylation and the COX-2/PGE? pathway in mice.

    PubMed

    Zhao, Hengguang; Luo, Fuling; Li, Hongzhong; Zhang, Li; Yi, Yongfen; Wan, Jingyuan

    2014-01-01

    Tetrandrine (TET) is a bisbenzylisoquinoline alkaloid that is isolated from the Stephania Tetrandra. It is known to possess anti-inflammatory and immunomodulatory effects. We have shown that TET can effectively suppress the production of bacterial lipopolysaccharide (LPS)-induced inflammatory mediators, including cyclooxygenases (COXs), in macrophages. However, whether TET has an antinociceptive effect on LPS-induced hyperalgesia is unknown. In the present study, we investigated the potential antinociceptive effects of TET and the mechanisms by which it elicits its effects on LPS-induced hyperalgesia. LPS effectively evoked hyperalgesia and induced the production of PGE2 in the sera, brain tissues, and cultured astroglia. TET pretreatment attenuated all of these effects. LPS also activated inhibitor of ?B (I?B) kinase ? (IKK?) and its downstream components in the I?B/nuclear factor (NF)-?B signaling pathway, including COX-2; the increase in expression levels of these components was significantly abolished by TET. Furthermore, in primary astroglia, knockdown of IKK?, but not IKK?, reversed the effects of TET on the LPS-induced increase in I?B phosphorylation, P65 phosphorylation, and COX-2. Our results suggest that TET can effectively exert antinociceptive effects on LPS-induced hyperalgesia in mice by inhibiting IKK? phosphorylation, which leads to the reduction in the production of important pain mediators, such as PGE2 and COX-2, via the IKK?/I?B/NF-?B pathway. PMID:24722146

  18. Lipid emulsions differentially affect LPS-induced acute monocytes inflammation: in vitro effects on membrane remodeling and cell viability.

    PubMed

    Boisramé-Helms, Julie; Delabranche, Xavier; Klymchenko, Andrey; Drai, Jocelyne; Blond, Emilie; Zobairi, Fatiha; Mely, Yves; Hasselmann, Michel; Toti, Florence; Meziani, Ferhat

    2014-11-01

    The aim of this study was to assess how lipid emulsions for parenteral nutrition affect lipopolysaccharide (LPS)-induced acute monocyte inflammation in vitro. An 18 h long LPS induced human monocyte leukemia cell stimulation was performed and the cell-growth medium was supplemented with three different industrial lipid emulsions: Intralipid(®), containing long-chain triglycerides (LCT--soybean oil); Medialipid(®), containing LCT (soybean oil) and medium-chain triglycerides (MCT--coconut oil); and SMOFlipid(®), containing LCT, MCT, omega-9 and -3 (soybean, coconut, olive and fish oils). Cell viability and apoptosis were assessed by Trypan blue exclusion and flow cytometry respectively. Monocyte composition and membrane remodeling were studied using gas chromatography and NR12S staining. Microparticles released in supernatant were measured by prothrombinase assay. After LPS challenge, both cellular necrosis and apoptosis were increased (threefold and twofold respectively) and microparticle release was enhanced (sevenfold) after supplementation with Medialipid(®) compared to Intralipid(®), SMOFlipid(®) and monocytes in the standard medium. The monocytes differentially incorporated fatty acids after lipid emulsion challenge. Finally, lipid-treated cells displayed microparticles characterized by disrupted membrane lipid order, reflecting lipid remodeling of the parental cell plasma membrane. Our data suggest that lipid emulsions differentially alter cell viability, monocyte composition and thereby microparticle release. While MCT have deleterious effects, we have shown that parenteral nutrition emulsion containing LCT or LCT and MCT associated to n-3 and n-9 fatty acids have no effect on endotoxin-induced cell death and inflammation. PMID:25038627

  19. Resveratrol Inhibits LPS-Induced MAPKs Activation via Activation of the Phosphatidylinositol 3-Kinase Pathway in Murine RAW 264.7 Macrophage Cells

    PubMed Central

    Liu, Bin; Deng, Yi-Shu; Zhan, Dong; Chen, Yuan-Li; He, Ying; Liu, Jing; Zhang, Zong-Ji; Sun, Jun; Lu, Di

    2012-01-01

    Background Resveratrol is a natural polyphenolic compound that has cardioprotective, anticancer and anti-inflammatory properties. We investigated the capacity of resveratrol to protect RAW 264.7 cells from inflammatory insults and explored mechanisms underlying inhibitory effects of resveratrol on RAW 264.7 cells. Methodology/Principal Findings Murine RAW 264.7 cells were treated with resveratrol (1, 5, and 10 µM) and/or LPS (5 µg/ml). Nitric oxide (NO) and prostaglandin E2 (PGE2) were measured by Griess reagent and ELISA. The mRNA and protein levels of proinflammatory proteins and cytokines were analysed by ELISA, RT-PCR and double immunofluorescence labeling, respectively. Phosphorylation levels of Akt, cyclic AMP-responsive element-binding protein (CREB), mitogen-activated protein kinases (MAPKs) cascades, AMP-activated protein kinase (AMPK) and expression of SIRT1(Silent information regulator T1) were measured by western blot. Wortmannin (1 µM), a specific phosphatidylinositol 3-kinase (PI3-K) inhibitor, was used to determine if PI3-K/Akt signaling pathway might be involved in resveratrol’s action on RAW 264.7 cells. Resveratrol significantly attenuated the LPS-induced expression of nitric oxide (NO), prostaglandin E2 (PGE2), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-? (TNF-?) and interleukin-1? (IL-1?) in RAW 264.7 cells. Resveratrol increased Akt phosphorylation in a time-dependent manner. Wortmannin, a specific phosphatidylinositol 3-kinase (PI3-K) inhibitor, blocked the effects of resveratrol on LPS-induced RAW 264.7 cells activation. In addition, PI3-K inhibition partially abolished the inhibitory effect of resveratrol on the phosphorylation of cyclic AMP-responsive element-binding protein (CREB) and mitogen-activated protein kinases (MAPKs) cascades. Meanwhile, PI3-K is essential for resveratrol-mediated phosphorylation of AMPK and expression of SIRT1. Conclusion and Implications This investigation demonstrates that PI3-K/Akt activation is an important signaling in resveratrol-mediated activation of AMPK phosphorylation and SIRT1 expression, and inhibition of phosphorylation of CREB and MAPKs activation, proinflammatory mediators and cytokines production in response to LPS in RAW 264.7 cells. PMID:22952890

  20. A TLR4/MD2 fusion protein inhibits LPS-induced pro-inflammatory signaling in hepatic stellate cells

    SciTech Connect

    Schnabl, Bernd [Department of Medicine, University of California San Diego, 9500 Gilman Drive, MC0702, La Jolla, CA 92093 (United States)], E-mail: beschnabl@ucsd.edu; Brandl, Katharina; Fink, Marina; Gross, Philipp [Department of Internal Medicine I, University of Regensburg (Germany); Taura, Kojiro [Department of Medicine, University of California San Diego, 9500 Gilman Drive, MC0702, La Jolla, CA 92093 (United States); Gaebele, Erwin; Hellerbrand, Claus; Falk, Werner [Department of Internal Medicine I, University of Regensburg (Germany)

    2008-10-17

    Activated hepatic stellate cells (HSCs) play a key role in hepatic fibrogenesis. In injured liver they are the main extracellular matrix protein producing cell type and further perpetuate hepatic injury by secretion of pro-inflammatory mediators. Since LPS-mediated signaling through toll-like receptor 4 (TLR4) has been identified as key fibrogenic signal in HSCs we aimed to test TLR4 as potential target of therapy via ligand-binding soluble receptors. Incubation of human HSCs with a fusion protein between the extracellular domain of TLR4 and MD2 which binds LPS inhibited LPS-induced NF{kappa}B and JNK activation. TLR4/MD2 abolished LPS-induced secretion of IL-6, IL-8, MCP1, and RANTES in HSCs. In addition, TLR4/MD2 fused to human IgG-Fc neutralized LPS activity. Since TLR4 mutant mice are resistant to liver fibrosis, the TLR4/MD2 soluble receptor might represent a new therapeutic molecule for liver fibrogenesis in vivo.

  1. A natural formulation (imoviral?) increases macrophage resistance to LPS-induced oxidative and inflammatory stress in vitro.

    PubMed

    Menghini, L; Leporini, L; Pintore, G; Ferrante, C; Recinella, L; Orlando, G; Vacca, M; Brunetti, L

    2014-01-01

    Imoviral? is a natural product formulation containing a mixture of uncaria, shiitake and ribes extracts. All ingredients are recognized as antioxidant, anti-inflammatory agent and immunomodulant. In order to evaluate the rational basis of extract mixture as immunomodulatory agent, we tested the effect of Imoviral? formulation on macrophage response to lipopolysaccharide (LPS)-induced stress. The effect was evaluated as variation of reactive oxygen species (ROS) and prostaglandin E2 (PGE2) production and as cytokine gene expression. The extract did not affect cell viability up to 250 ?g/ml. Treatment with extract (10-150 ?g/ml) reduced ROS and PGE2 production as well as IL-8 and TNF-? gene expression. A pre-treatment with extract blunted LPS-induced production of ROS and PGE2, markers of oxidative and inflammatory stress, as well as the gene expression of all cytokines tested, indicators, in vitro, of immune response activation. In conclusion, we demonstrated that Imoviral? formulation could be a useful tool to modulate the immune function, reducing the oxidative and inflammatory markers related to bacterial attack. Experimental data suggest that Imoviral? extract mixture could also represent a preventive pharmacological strategy to enhance cell resistance to bacterial infections. PMID:25620186

  2. Polymethoxyflavone Apigenin-Trimethylether Suppresses LPS-Induced Inflammatory Response in Nontransformed Porcine Intestinal Cell Line IPEC-J2

    PubMed Central

    Farkas, Orsolya; Palócz, Orsolya; Pászti-Gere, Erzsébet; Gálfi, Péter

    2015-01-01

    The in vitro anti-inflammatory effect of apigenin and its trimethylated analogue (apigenin-trimethylether) has been investigated in order to evaluate whether these flavonoids could attenuate LPS-induced inflammation in IPEC-J2 non-transformed intestinal epithelial cells. Levels of IL-6, IL-8, TNF-?, and COX-2 mRNA were measured as a marker of inflammatory response. The extracellular H2O2 level in IPEC-J2 cells was also monitored by Amplex Red assay. Our data revealed that both compounds had significant lowering effect on the inflammatory response. Apigenin (at 25??M) significantly decreased gene expression of IL-6 in LPS-treated cells, while apigenin-trimethylether in the same concentration did not influence IL-6 mRNA level. Both apigenin and apigenin-trimethylether reduced IL-8 gene expression significantly. TNF-? mRNA level was decreased by apigenin-trimethylether, which was not influenced by apigenin. Treatment with both flavonoids caused significant reduction in the mRNA level of COX-2, but the anti-inflammatory effect of the methylated analogue was more effective than the unmethylated one. Furthermore, both flavonoids reduced significantly the level of extracellular H2O2 compared to the control cells. In conclusion, the methylated apigenin analogue could avoid LPS-induced intestinal inflammation and it could be applied in the future as an effective anti-inflammatory compound.

  3. Anti-Inflammatory Effect of Procyanidins from Wild Grape (Vitis amurensis) Seeds in LPS-Induced RAW 264.7 Cells

    PubMed Central

    Bak, Min-Ji; Truong, Van Long; Kang, Hey-Sook; Jun, Mira; Jeong, Woo-Sik

    2013-01-01

    In the present study, the anti-inflammatory effect and underlying mechanisms of wild grape seeds procyanidins (WGP) were examined using lipopolysaccharide- (LPS-) stimulated RAW 264.7 cells. We used nitric oxide (NO) and prostaglandin E2 (PGE2) and reactive oxygen species (ROS) assays to examine inhibitory effect of WGP and further investigated the mechanisms of WGP suppressed LPS-mediated genes and upstream expression by Western blot and confocal microscopy analysis. Our data indicate that WGP significantly reduced NO, PGE2, and ROS production and also inhibited the expression of proinflammatory mediators such as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expressions. Consistently, WGP significantly reduced LPS-stimulated expression of proinflammatory cytokines such as tumor necrosis factor ? (TNF-?) and interleukin- (IL-) 1?. Moreover, WGP prevented nuclear translocation of nuclear factor-?B (NF?B) p65 subunit by reducing inhibitory ?B-? (I?B?) and NF?B phosphorylation. Furthermore, we found that WGP inhibited LPS-induced phosphorylation of p38 mitogen-activated protein kinase (MAPK). Taken together, our results demonstrated that WGP exerts potent anti-inflammatory activity through the inhibition of iNOS and COX-2 by regulating NF?B and p38 MAPK pathway. PMID:24260615

  4. A comparative study on hulled adlay and unhulled adlay through evaluation of their LPS-induced anti-inflammatory effects, and isolation of pure compounds.

    PubMed

    Choi, Goeun; Han, Ah-Reum; Lee, Joo Hee; Park, Ji-Youn; Kang, Unwoo; Hong, Jongki; Kim, Yeong Shik; Seo, Eun-Kyoung

    2015-03-01

    Coicis semen (=the hulled seed of Coix lacryma-jobi L. var. ma-yuen (Rom.Caill.) Stapf; Gramineae), commonly known as adlay and Job's tears, is widely used in traditional medicine and as a nutritious food. Bioassay-guided fractionation of the AcOEt fraction of unhulled adlays, using measurement of nitric oxide (NO) production on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells, led to the isolation and identification of two new stereoisomers, (+)-(7'S,8'R,7?S,8?R)-guaiacylglycerol ?-O-4'-dihydrodisinapyl ether (1) and (+)-(7'S,8'R,7?R,8?R)-guaiacylglycerol ?-O-4'-dihydrodisinapyl ether (2), together with six known compounds, 3-8. Compounds 3 and 4 exhibited inhibitory activities on LPS-induced NO production with IC50 values of 1.4 and 3.7??M, respectively, and suppressed inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expressions in RAW 264.7 macrophage cells. Simple high-performance liquid chromatography with ultraviolet detection (HPLC/UV) was used to compare the AcOEt fraction of unhulled adlays responsible for the anti-inflammatory activity in RAW 264.7 cells and the inactive AcOEt fraction of hulled adlays. PMID:25766911

  5. Selenium inhibits LPS-induced pro-inflammatory gene expression by modulating MAPK and NF-?B signaling pathways in mouse mammary epithelial cells in primary culture.

    PubMed

    Zhang, Wen; Zhang, Runxiang; Wang, Tiancheng; Jiang, Haichao; Guo, Mengyao; Zhou, Ershun; Sun, Yong; Yang, Zhengtao; Xu, Shiwen; Cao, Yongguo; Zhang, Naisheng

    2014-04-01

    Mastitis is characterized by an inflammation of the mammary gland of dairy animals and humans; this condition is one of the major causes of economic losses in dairy industries. Selenium (Se), a biological trace element, modulates the functions of many regulatory proteins in signal transduction and provides advantages for animals with inflammatory diseases, including mastitis. The current study aimed to assess the protective effects and the active mechanism of Na(2)SeO(3) against lipopolysaccharide (LPS)-induced inflammation in mouse mammary epithelial cells (MMECs). Our results showed that LPS-induced expressions of cyclooxygenase-2 and tumor necrosis factor-? significantly decreased after Se was supplemented to Se-deficient MMECs. Na(2)SeO(3) also suppressed LPS-induced nuclear factor-?B activation, inhibitory kappa B degradation, and ERK, JNK, and P38 phosphorylation in a dose-dependent manner. These results suggested that Se functions as an anti-inflammatory agent in mastitis. PMID:24202549

  6. Salvia miltiorrhiza water-soluble extract, but not its constituent salvianolic acid B, abrogates LPS-induced NF-?B signalling in intestinal epithelial cells

    PubMed Central

    Kim, J S; Narula, A S; Jobin, C

    2005-01-01

    Herbal medicine has become an increasing popular therapeutic alternative among patients suffering from various inflammatory disorders. The Salvia miltiorrhizae water-soluble extract (SME) have been shown to possess antioxidant and anti-inflammatory properties in vitro. However, the mechanism of action and impact of SME on LPS-induced gene expression is still unknown. We report that SME significantly abrogated LPS-induced I?B phosphorylation/degradation, NF-?B transcriptional activity and ICAM-1 gene expression in rat IEC-18 cells. Chromatin immunoprecipitation assay demonstrated that LPS-induced RelA recruitment to the ICAM-1 gene promoter was inhibited by SME. Moreover, in vitro kinase assay showed that SME directly inhibits LPS induced I?B kinase (IKK) activity in IEC-18 cells. To investigate the physiological relevance of SME inhibitory activity on NF-?B signalling, we used small intestinal explants and primary intestinal epithelial cells derived from a transgenic mouse expressing the enhanced green fluorescent protein (EGFP) under the transcriptional control of NF-?B cis-elements (cis-NF-?BEGFP). SME significantly blocked LPS-induced EGFP expression and I?B? phosphorylation in intestinal explants and primary IECs, respectively. However, salvianolic acid B, an activate component of SME did not inhibit NF-?B transcriptional activity and I?B phosphorylation/degradation in IEC-18 cells. These results indicate that SME blocks LPS-induced NF-?B signalling pathway by targeting the IKK complex in intestinal epithelial cells. Modulation of bacterial product-mediated NF-?B signalling by natural plant extracts may represent an attractive strategy towards the prevention and treatment of intestinal inflammation. PMID:15996193

  7. EFFECTS OF NITRIC OXIDE SYNTHASE INHIBITION IN LIPOPOLYSACCHARIDE-INDUCED SEPSIS IN MICE

    Microsoft Academic Search

    BAHAR TUNÇTAN; ORHAN ULUDA ?; SEDAT ALTU ?; NURETTIN ABACIO ?

    1998-01-01

    In the present study, we have investigated the effects of nitric oxide (NO) synthase inhibition on mortality in lipopolysaccharide (LPS)-induced sepsis in mice. Serum nitrite levels peaked at 15 h after an injection of LPS (10 mg kg?1, i.p.). Aminoguanidine, a selective inducible NO synthase (iNOS) inhibitor, at a dose of 100 mg kg?1significantly reduced the LPS-induced increase in nitrite

  8. Anandamide, Acting via CB2 Receptors, Alleviates LPS-Induced Neuroinflammation in Rat Primary Microglial Cultures

    PubMed Central

    Malek, Natalia; Popiolek-Barczyk, Katarzyna; Mika, Joanna; Przewlocka, Barbara; Starowicz, Katarzyna

    2015-01-01

    Microglial activation is a polarized process divided into potentially neuroprotective phenotype M2 and neurotoxic phenotype M1, predominant during chronic neuroinflammation. Endocannabinoid system provides an attractive target to control the balance between microglial phenotypes. Anandamide as an immune modulator in the central nervous system acts via not only cannabinoid receptors (CB1 and CB2) but also other targets (e.g., GPR18/GPR55). We studied the effect of anandamide on lipopolysaccharide-induced changes in rat primary microglial cultures. Microglial activation was assessed based on nitric oxide (NO) production. Analysis of mRNA was conducted for M1 and M2 phenotype markers possibly affected by the treatment. Our results showed that lipopolysaccharide-induced NO release in microglia was significantly attenuated, with concomitant downregulation of M1 phenotypic markers, after pretreatment with anandamide. This effect was not sensitive to CB1 or GPR18/GPR55 antagonism. Administration of CB2 antagonist partially abolished the effects of anandamide on microglia. Interestingly, administration of a GPR18/GPR55 antagonist by itself suppressed NO release. In summary, we showed that the endocannabinoid system plays a crucial role in the management of neuroinflammation by dampening the activation of an M1 phenotype. This effect was primarily controlled by the CB2 receptor, although functional cross talk with GPR18/GPR55 may occur. PMID:26090232

  9. The regulation of cytochrome P450 2E1 during LPS-induced inflammation in the rat

    SciTech Connect

    Abdulla, Dalya [Department of Pharmacology, Sir Charles Tupper Medical Bldg., Dalhousie University, Halifax, Nova Scotia, B3H 4H7 (Canada); Goralski, Kerry B. [Department of Pharmacology, Sir Charles Tupper Medical Bldg., Dalhousie University, Halifax, Nova Scotia, B3H 4H7 (Canada); College of Pharmacy, Burbidge Building, Dalhousie University, Halifax, Nova Scotia, B3H 3J5 (Canada); Renton, Kenneth W. [Department of Pharmacology, Sir Charles Tupper Medical Bldg., Dalhousie University, Halifax, Nova Scotia, B3H 4H7 (Canada)]. E-mail: Ken.Renton@dal.ca

    2006-10-01

    It is well known that inflammatory and infectious conditions differentially regulate cytochrome P450 (P450)-mediated drug metabolism in the liver. We have previously outlined a potential pathway for the downregulation in hepatic cytochrome P450 following LPS-mediated inflammation in the CNS (Abdulla, D., Goralski, K.B., Garcia Del Busto Cano, E., Renton, K.W., 2005. The signal transduction pathways involved in hepatic cytochrome P450 regulation in the rat during an LPS-induced model of CNS inflammation. Drug Metab. Dispos). The purpose of this study was to outline the effects of LPS-induced peripheral and central nervous system inflammation on hepatic cytochrome P450 2E1 (CYP2E1) in vivo, an enzyme that plays an important role in various physiological and pathological states. We report an increase in hepatic mRNA expression of CYP2E1 that occurred as early as 2-3 h following either the intraperitoneal (i.p.) injection of 5 mg/kg LPS or i.c.v. administration of 25 {mu}g of LPS. This increase in CYP2E1 mRNA expression was sustained for 24 h. In sharp contrast to the increase in hepatic CYP2E1 mRNA, we observed a significant reduction in the catalytic activity of this enzyme 24 h following either the i.c.v. or i.p. administration of LPS. Cycloheximide or actinomycin-D did not change the LPS-mediated downregulation in hepatic CYP2E1 catalytic activity. Our results support the idea that LPS acts at two different levels to regulate hepatic CYP2E1: a transcriptional level to increase CYP2E1 mRNA expression and a post-transcriptional level to regulate CYP2E1 protein and activity.

  10. Lipopolysaccharide (LPS) recognition in macrophages. Participation of LPS-binding protein and CD14 in LPS-induced adaptation in rabbit peritoneal exudate macrophages.

    PubMed Central

    Mathison, J; Wolfson, E; Steinemann, S; Tobias, P; Ulevitch, R

    1993-01-01

    Exposure of rabbit peritoneal exudate macrophages (PEM) or whole blood to picomolar concentrations of LPS induces adaptation or hyporesponsiveness to LPS. Because of the importance of plasma LPS-binding protein (LBP) and the macrophage cell membrane protein CD14 in recognition of LPS, we examined the effect of LBP on LPS-induced adaptation in PEM. PEM exposed to LPS in the presence of LBP for 8 h were markedly less responsive to subsequent stimulation by LPS than monocytes/macrophages (M phi) adapted in the absence of LBP. LPS-induced expression of TNF was sharply reduced in LBP-LPS-adapted PEM, but in contrast these cells remained fully responsive to Staphylococcus aureus peptidoglycan. We considered that specific hyporesponsiveness in LPS-adapted M phi or in blood monocytes could be due to decreased expression of CD14 or diminished binding of LBP-LPS complexes to CD14. However, flow cytometry analysis revealed only minimal reduction of CD14 expression or CD14-dependent binding of a fluorescent LPS derivative when normo- and hyporesponsive cells were compared. These results show that complexes of LPS and LBP are more effective than LPS alone in inducing adaptation to LPS, and LPS-induced hyporesponsiveness probably results from changes in cellular elements distinct from CD14 that are involved in either LPS recognition or LPS-specific signal transduction. Images PMID:7691891

  11. KIOM-79 inhibits LPS-induced iNOS gene expression by blocking NF-kappaB/Rel and p38 kinase activation in murine macrophages.

    PubMed

    Jeon, Young Jin; Li, Mei Hong; Lee, Kun Yeong; Kim, Jin Sook; You, Ho Jin; Lee, Seog Ki; Sohn, Hong Moon; Choi, Sang Joon; Koh, Jae Woong; Chang, In Youb

    2006-11-01

    We demonstrate that KIOM-79, combined extracts obtained from Magnolia officinalis, Pueraria lobata, Glycyrrhiza uralensis, and Euphorbia pekinensis, inhibits LPS-induced expression of iNOS gene in RAW 264.7 cells. Treatment of RAW 264.7 cells with KIOM-79 inhibited LPS-stimulated nitric oxide production in a dose-related manner. Immunohisto-chemical staining of iNOS and RT-PCR analysis showed that the decrease of NO was due to the inhibition of iNOS gene expression. Immunostaining of p65, EMSA, and reporter gene assay showed that KIOM-79 inhibited NF-kappa/Rel nuclear translocation, DNA binding, and transcriptional activation, respectively. Western immunoblot analysis of p38 kinase showed KIOM-79 significantly inhibited the phosphoylation of p38 kinase which is important in the regulation of iNOS gene expression. Collectively, this series of experiments indicates that KIOM inhibits iNOS gene expression by blocking NF-kappa/Rel and p38 kinase signaling. Due to the critical role that NO release plays in mediating inflammatory responses, the inhibitory effects of KIOM-79 on iNOS suggest that KIOM-79 may represent a useful anti-inflammatory agent. PMID:16806764

  12. Neolignans from the fruits of Magnolia obovata and their inhibition effect on NO production in LPS-induced RAW 264.7 cells.

    PubMed

    Seo, Kyeong-Hwa; Lee, Dae-Young; Lee, Dong-Sung; Park, Ji-Hae; Jeong, Rak-Hun; Jung, Ye-Jin; Shrestha, Sabina; Chung, In-Sik; Kim, Geum-Soog; Kim, Youn-Chul; Baek, Nam-In

    2013-09-01

    Three new neolignans, named 9-methoxyobovatol (6), magnobovatol (7), and 2-hydroxyobovaaldehyde (9), along with six known ones, magnolol (1), honokiol (2), isomagnolol (3), obovatol (4), obovatal (5), and obovaaldehyde (8), were isolated from the fruits of Magnolia obovata using silica gel and ODS column chromatography. From the results of spectroscopic data including EIMS, IR, 1H- and 13C-NMR, DEPT, and 2D-NMR (gCOSY, gHSQC, gHMBC), the chemical structures were determined. All isolated compounds were evaluated for inhibition activity on nitric oxide production in LPS-induced RAW 264.7 cells, and compounds 1-4, 6, 7, and 9 showed significant activity with IC50 values of 15.8 ± 0.3, 3.3 ± 1.2, 14.1 ± 0.9, 6.2 ± 1.2, 14.8 ± 2.3, 14.2 ± 1.2, and 14.8 ± 3.2 µM, respectively, without any visible toxic effect. PMID:23970426

  13. LPS-induced suppression of macrophage cholesterol efflux is mediated by adipocyte enhancer-binding protein 1.

    PubMed

    Majdalawieh, Amin; Ro, Hyo-Sung

    2009-07-01

    Macrophages facilitate clearance of cholesterol from the body via reverse cholesterol transport (RCT). The first event in RCT is internalization of modified low density lipoprotein by macrophages, upon which PPARgamma1 and LXRalpha signaling pathways are turned on, leading to the transactivation of a cascade of genes (e.g. ABCA1 and ABCG1), whose products promote macrophage cholesterol efflux. Down-regulation of macrophage cholesterol efflux mediators leads to an imbalance in cholesterol homeostasis, promoting foam cell formation. Lipopolysaccharide (LPS) has been shown to suppress PPARgamma1 and its downstream target genes in macrophages, inducing foam cell formation; a key mechanism proposed to underlie bacterial infection-induced atherosclerosis. Herein, we show that adipocyte enhancer-binding protein 1 (AEBP1) is up-regulated during monocyte differentiation. Moreover, we provide experimental evidence suggesting that AEBP1 expression is induced by LPS, and that LPS-induced down-regulation of pivotal macrophage cholesterol efflux mediators, leading to foam cell formation, is largely mediated by AEBP1. Although AEBP1-independent pathways seem to contribute to these LPS effects, such pathways can only mediate lesser and delayed effects of LPS on macrophage cholesterol efflux and development of foam cells. We speculate that AEBP1 may serve as a potential therapeutic target for the prevention/treatment of bacterial infection-induced atherosclerosis. PMID:19166963

  14. Functional Toll-like receptor 4 expressed in lactotrophs mediates LPS-induced proliferation in experimental pituitary hyperplasia

    SciTech Connect

    Sabatino, María Eugenia; Sosa, Liliana del Valle; Petiti, Juan Pablo; Mukdsi, Jorge Humberto [Centro de Microscopía Electrónica, Instituto de Investigaciones en Ciencias de la Salud (INICSA-CONICET), Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Av. Enrique Barros y Enfermera Gordillo, Ciudad Universitaria, CP 5000, Córdoba (Argentina); Mascanfroni, Iván Darío; Pellizas, Claudia Gabriela [Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Av. Haya de la Torre y Medina Allende, Ciudad Universitaria, CP 5000, Córdoba (Argentina); Gutiérrez, Silvina; Torres, Alicia Inés [Centro de Microscopía Electrónica, Instituto de Investigaciones en Ciencias de la Salud (INICSA-CONICET), Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Av. Enrique Barros y Enfermera Gordillo, Ciudad Universitaria, CP 5000, Córdoba (Argentina); De Paul, Ana Lucía, E-mail: adepaul@cmefcm.uncor.edu [Centro de Microscopía Electrónica, Instituto de Investigaciones en Ciencias de la Salud (INICSA-CONICET), Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Av. Enrique Barros y Enfermera Gordillo, Ciudad Universitaria, CP 5000, Córdoba (Argentina)

    2013-11-15

    Toll like receptor 4 (TLR4) has been characterized for its ability to recognize bacterial endotoxin lipopolysaccharide (LPS). Considering that infections or inflammatory processes might contribute to the progression of pituitary tumors, we analyzed the TLR4 functional role by evaluating the LPS effect on lactotroph proliferation in primary cultures from experimental pituitary tumors, and examined the involvement of PI3K-Akt and NF-?B activation in this effect. In addition, the role of 17?-estradiol as a possible modulator of LPS-induced PRL cell proliferation was further investigated. In estrogen-induced hyperplasic pituitaries, LPS triggered lactotroph cell proliferation. However, endotoxin failed to increase the number of lactotrophs taking up BrdU in normal pituitaries. Moreover, incubation with anti-TLR4 antibody significantly reduced LPS-induced lactotroph proliferation, suggesting a functional role of this receptor. As a sign of TLR4 activation, an LPS challenge increased IL-6 release in normal and tumoral cells. By flow cytometry, TLR4 baseline expression was revealed at the plasma membrane of tumoral lactotrophs, without changes noted in the percentage of double PRL/TLR4 positive cells after LPS stimulus. Increases in TLR4 intracellular expression were detected as well as rises in CD14, p-Akt and NF-?B after an LPS challenge, as assessed by western blotting. The TLR4/PRL and PRL/NF-?B co-localization was also corroborated by immunofluorescence and the involvement of PI3K/Akt signaling in lactotroph proliferation and IL-6 release was revealed through the PI3K inhibitor Ly-294002. In addition, 17?-estradiol attenuated the LPS-evoked increase in tumoral lactotroph proliferation and IL-6 release. Collectively these results demonstrate the presence of functional TLR4 in lactotrophs from estrogen-induced hyperplasic pituitaries, which responded to the proliferative stimulation and IL-6 release induced by LPS through TLR4/CD14, with a contribution of the PI3K-Akt and NF-?B signaling pathways. - Highlights: • In hyperplastic pituitaries, LPS triggered the lactotroph cell proliferation and IL-6 release. • Functional Toll-like receptor 4 (TLR4) is expressed at the plasma membrane of tumoral lactotrophs. • Increases in TLR4 and CD14 intracellular expression levels were detected after an LPS challenge. • The proliferative stimulation and IL-6 release involved the PI3K-Akt pathway and NF-?B activation. • 17?-estradiol attenuated the LPS-evoked tumoral lactotroph proliferation and IL-6 secretion.

  15. ?-Ionone attenuates LPS-induced pro-inflammatory mediators such as NO, PGE2 and TNF-? in BV2 microglial cells via suppression of the NF-?B and MAPK pathway.

    PubMed

    Kang, Chang-Hee; Jayasooriya, Rajapaksha Gendara Prasad Tharanga; Choi, Yung Hyun; Moon, Sung-Kwon; Kim, Wun-Jae; Kim, Gi-Young

    2013-03-01

    ?-Ionone, a precursor of carotenoids, possesses a variety of biological properties such as anti-cancerous, anti-mutagenic and anti-microbial activity. Nevertheless, anti-inflammatory effects of ?-ionone remain unknown. In this study, we investigated whether ION attenuates the expression of lipopolysaccharide (LPS)-induced pro-inflammatory mediators such as nitric oxide (NO), prostaglandin E2 (PGE2) and tumor necrosis factor-? (TNF-?) in BV2 microglia cells. Our data showed that ?-ionone significantly inhibits secretion of NO, PGE2 and TNF-?. ?-Ionone also inhibits the expression of inducible NO synthesis (iNOS), cyclooxygenase-2 (COX-2) and TNF-? protein and their mRNA in LPS-stimulated BV2 microglia cells. In addition, ?-ionone significantly reduced DNA-binding activity of nuclear factor-?B (NF-?B) through suppression of nuclear translocation of p50 and p65. We showed that NF-?B inhibitor N-acetyl-L-cysteine (NAC) effectively attenuates the expression of LPS-stimulated iNOS, COX-2 and TNF-?. We also found that LPS-induced NF-?B activation is significantly regulated through inhibition of Akt phosphorylation in the presence of ?-ionone. Finally, we showed that ?-ionone substantially inhibits the phosphorylation of mitogen-activated protein kinases (MAPKs), including ERK1/2, p38 and JNK, which are closely related to regulation of pro-inflammatory mediator secretion. Taken together, these data imply that ?-ionone regulates LPS-induced NF-?B-dependent inflammatory pathways through suppression of Akt and MAPK activation. PMID:23268108

  16. Riluzole partially rescues age-associated, but not LPS-induced, loss of glutamate transporters and spatial memory

    PubMed Central

    Brothers, Holly M.; Bardou, Isabelle; Hopp, Sarah C.; Kaercher, Roxanne M.; Corona, Angela W.; Fenn, Ashley M.; Godbout, Jonathan P.; Wenk, Gary L.

    2013-01-01

    Impaired memory may result from synaptic glutamatergic dysregulation related to chronic neuroinflammation. GLT1 is the primary excitatory amino acid transporter responsible for regulating extracellular glutamate levels in the hippocampus. We tested the hypothesis that if impaired spatial memory results from increased extracellular glutamate due to age or experimentally induced chronic neuroinflammation in the hippocampus, then pharmacological augmentation of the glutamate transporter GLT1 will attenuate deficits in a hippocampal-dependent spatial memory task. The profile of inflammation-related genes and proteins associated with normal aging, or chronic neuroinflammation experimentally-induced via a four-week LPS infusion into the IVth ventricle, were correlated with performance in the Morris water maze following treatment with Riluzole, a drug that can enhance glutamate clearance by increasing GLT1 expression. Age-associated inflammation was qualitatively different from LPS-induced neuroinflammation in young rats. LPS produced a pro-inflammatory phenotype characterized by increased IL-1? expression in the hippocampus, whereas aging was not associated with a strong central pro-inflammatory response but with a mixed peripheral immune phenotype. Riluzole attenuated the spatial memory impairment, the elevation of serum cytokines and the decrease in GLT1 gene expression in Aged rats, but had no effect on young rats infused with LPS. Our findings highlight the therapeutic potential of reducing glutamatergic function upon memory impairment in neurodegenerative diseases associated with aging. PMID:23709339

  17. Analgesic and anti-hyperalgesic effects of epidural morphine in an equine LPS-induced acute synovitis model.

    PubMed

    van Loon, Johannes P A M; Menke, Eveline S; L'ami, Jiske J; Jonckheer-Sheehy, Valerie S M; Back, Willem; René van Weeren, P

    2012-08-01

    Epidural morphine is widely used in veterinary medicine, but there is no information about the anti-hyperalgesic and anti-inflammatory effects in acute inflammatory joint disease in horses. The analgesic, anti-hyperalgesic and anti-inflammatory effects of epidural morphine (100mg/animal or 0.17 ± 0.02 mg/kg) were therefore investigated in horses with acute synovitis. In a cross-over study, synovitis was induced in the talocrural joint by intra-articular lipopolysaccharide (LPS). The effect of epidural morphine was evaluated using physiological, kinematic and behavioural variables. Ranges of motion (ROM) of the metatarsophalangeal and talocrural joints were measured, clinical lameness scores and mechanical nociceptive thresholds (MNTs) were assessed and synovial fluid inflammatory markers were measured. The injection of LPS induced transient synovitis, resulting in clinical lameness, decreased ranges of motion in the talocrural and metatarsophalangeal joints, decreased limb loading at rest and increased composite pain scores. Epidural morphine resulted in a significant improvement in clinical lameness, increased ROM and improved loading of the LPS-injected limb at rest, with no effects on synovial fluid inflammatory markers. Morphine prevented a decrease in MNT and, hence, inhibited the development of hyperalgesia close to the dorsal aspect of inflamed talocrural joints. This study showed that epidural morphine provides analgesic and anti-hyperalgesic effects in horses with acute synovitis, without exerting peripheral anti-inflammatory effects. PMID:22342215

  18. A novel MyD-1 (SIRP-1alpha) signaling pathway that inhibits LPS-induced TNFalpha production by monocytes.

    PubMed

    Smith, Rosemary E; Patel, Vanshree; Seatter, Sandra D; Deehan, Maureen R; Brown, Marion H; Brooke, Gareth P; Goodridge, Helen S; Howard, Christopher J; Rigley, Kevin P; Harnett, William; Harnett, Margaret M

    2003-10-01

    MyD-1 (CD172) is a member of the family of signal regulatory phosphatase (SIRP) binding proteins, which is expressed on human CD14+ monocytes and dendritic cells. We now show a novel role for MyD-1 in the regulation of the innate immune system by pathogen products such as lipopolysaccharide (LPS), purified protein derivative (PPD), and Zymosan. Specifically, we demonstrate that ligation of MyD-1 on peripheral blood mononuclear cells (PBMCs) inhibits tumor necrosis factor alpha (TNFalpha) secretion but has no effect on other cytokines induced in response to each of these products. In an attempt to understand the molecular mechanisms underlying this surprisingly selective effect we investigated signal transduction pathways coupled to MyD-1. Ligation of the SIRP was found to recruit the tyrosine phosphatase SHP-2 and promote sequential activation of phosphatidylinositol (PI) 3-kinase, phospholipase D, and sphingosine kinase. Inhibition of LPS-induced TNFalpha secretion by MyD-1 appears to be mediated by this pathway, as the PI 3-kinase inhibitor wortmannin restores normal LPS-driven TNFalpha secretion. MyD-1-coupling to this PI 3-kinase-dependent signaling pathway may therefore present a novel target for the development of therapeutic strategies for combating TNFalpha production and consequent inflammatory disease. PMID:12805067

  19. I?B? is an essential co-activator for LPS-induced IL-1? transcription in vivo

    PubMed Central

    Scheibel, Melanie; Klein, Bettina; Merkle, Heidrun; Schulz, Manon; Fritsch, Ralph; Greten, Florian R.; Arkan, Melek C.; Schneider, Günter

    2010-01-01

    Inhibitor of ?B (I?B) ? (I?B?) represents one of the major primary regulators of NF-?B in mammals. In contrast to the defined regulatory interplay between NF-?B and I?B?, much less is known about the biological function of I?B?. To elucidate the physiological role of I?B? in NF-?B signaling in vivo, we generated I?B?-deficient mice. These animals proved to be highly refractory to LPS-induced lethality, accompanied by a strong reduction in sepsis-associated cytokine production. In response to LPS, I?B? is recruited to the IL-1? promoter forming a complex with the NF-?B subunits RelA/c-Rel required for IL-1? transcription. Further transcriptome analysis of LPS-stimulated wild-type and I?B?-deficient BM-derived macrophages revealed several other genes with known regulatory functions in innate immunity arguing that a subset of NF-?B target genes is under control of I?B?. Collectively, these findings provide an essential proinflammatory role for I?B? in vivo, and establish a critical function for I?B? as a transcriptional coactivator under inflammatory conditions. PMID:20975042

  20. Nicotine exaggerates LPS-induced airway hyperreactivity via JNK-mediated up-regulation of Toll-like receptor 4.

    PubMed

    Xu, Yuan; Zhang, Yaping; Cardell, Lars-Olaf

    2014-09-01

    Tobacco smokers often display increased airway hyperreactivity (AHR) when faced with bacterial infections. The present study uses a murine organ-culture model to dissect the mechanisms involved in this exaggerated smooth muscle response. Nicotine simulates the effects of smoking, and LPS represents bacterial infection. Contractile responses of isolated murine tracheal segments were analyzed in myographs after organ culture with increasing concentrations of LPS and/or nicotine for 4 days with or without specific MAPK inhibitors. Nicotine's effect on the expression of cell surface Toll-like receptors (TLRs), MCP-1, COX-2, and TNF-? were examined by real-time PCR. Increased protein expression was verified by immunohistochemistry. LPS concentration-dependently increased contractile responses to bradykinin and des-Arg(9)-bradykinin. A combination of nicotine and low-dose LPS caused powerful synergistic contractions along with increased kinin receptor expression. Specific kinin B1 and B2 receptor inhibitors blocked this reaction. Nicotine increased mRNA and protein expression of TLR4 and -6 in the epithelium and smooth muscle layer, with MCP-1 and COX-2 mRNA increasing in parallel. Specific inhibition of JNK attenuated nicotine's effects. In conclusion, long-term exposure to nicotine up-regulated the expression of TLR4 and -6 via a JNK-related pathway, causing an exaggeration of the LPS-induced local airway inflammation and increased AHR. This might offer a mechanistic explanation to the increased AHR seen in tobacco smokers confronted with bacterial infections. PMID:24669857

  1. Primary in vitro plaque-forming cell response to DAGG-Ficoll: LPS-induced enhancement mediated by interleukin-1.

    PubMed Central

    Curtis, J L; Nordin, A A

    1984-01-01

    The specific primary in vitro plaque-forming cell (PFC) response of C57B1/6 nu/nu spleen cells to the Type 2 T-independent (TI-2) antigen DAGG-Ficoll was analysed in the absence of T cell help in a serum-free medium. Lipopolysaccharide (LPS) enhancement of the antigen-specific response was shown to be mediated by soluble factors contained in the supernatants of LPS-induced bone marrow-derived macrophages. The activity of these supernatants was not associated with residual LPS, since the antigen-specific response of B cells from mice genetically deficient in LPS receptors was equally well enhanced. The activity of these supernatants was associated with interleukin-1 (IL-1) and partially purified IL-1 prepared from P388D1 cells also enhanced the primary in vitro response to DAGG-Ficoll. Limiting dilution analysis experiments showed that only in the presence of exogenously added IL-1 could a single cell type, presumably the B cells, be shown to be limiting. PMID:6378771

  2. Madecassoside suppresses LPS-induced TNF-alpha production in cardiomyocytes through inhibition of ERK, p38, and NF-kappaB activity.

    PubMed

    Cao, Wei; Li, Xiao-Qiang; Zhang, Xiao-Nan; Hou, Ying; Zeng, Ai-Guo; Xie, Yan-Hua; Wang, Si-Wang

    2010-07-01

    Madecassoside (MA) is a major triterpenoid component of Centella asiatica that has a wide range of biological activities, including wound-healing and antioxidative activities. In the present study, we evaluated the therapeutic effect of MA on rat cardiac dysfunction during sepsis induced by lipopolysaccharide (LPS), as well as the possible mechanism. Pretreatment of the neonatal rat cardiomyocytes with MA inhibited LPS-induced TNF-alpha production in a concentration-dependent manner. In addition, pretreatment of the rats with MA (20 mg/kg, i.g.) significantly inhibited the elevation of plasma TNF-alpha, delayed the fall of mean arterial blood pressure, and attenuated the tachycardia induced by LPS. We further observed that MA prevented the LPS-induced nuclear factor-kappa B (NF-kappaB) translocation from the cytoplasm into the nucleus, and inhibited the LPS-induced phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and p38. These results suggest that MA inhibits LPS-stimulated TNF-alpha production through the blocking of ERK1/2, p38 and NF-kappaB pathways in cardiomyocytes. MA may have cardioprotective effects in LPS-mediated sepsis. PMID:20381648

  3. The CO donor CORM-2 inhibits LPS-induced vascular cell adhesion molecule-1 expression and leukocyte adhesion in human rheumatoid synovial fibroblasts

    PubMed Central

    Chi, Pei-Ling; Chuang, Yu-Chen; Chen, Yu-Wen; Lin, Chih-Chung; Hsiao, Li-Der; Yang, Chuen-Mao

    2014-01-01

    BACKGROUND AND PURPOSE Infection with Gram-negative bacteria has been recognized as an initiator of rheumatoid arthritis, which is characterized by chronic inflammation and infiltration of immune cells. Carbon monoxide (CO) exhibits anti-inflammatory properties. Here we have investigated the detailed mechanisms of vascular cell adhesion molecule-1 (VCAM-1) expression induced by LPS and if CO inhibited LPS-induced leukocyte adhesion to synovial fibroblasts by suppressing VCAM-1 expression. EXPERIMENTAL APPROACH Human rheumatoid arthritis synovial fibroblasts (RASFs) were incubated with LPS and/or the CO-releasing compound CORM-2. Effects of LPS on VCAM-1 levels were determined by analysing mRNA expression, promoter activity, protein expression, and immunohistochemical staining. The molecular mechanisms were investigated by determining the expression, activation, and binding activity of transcriptional factors using target signal antagonists. KEY RESULTS CORM-2 significantly inhibited inflammatory responses in LPS-treated RASFs by down-regulating the expression of adhesion molecule VCAM-1 and leukocyte infiltration. The down-regulation of LPS-induced VCAM-1 expression involved inhibition of the expression of phosphorylated-NF-?B p65 and AP-1 (p-c-Jun, c-Jun and c-Fos mRNA levels). These results were confirmed by chromatin immunoprecipitation assay to detect NF-?B and AP-1 DNA binding activity. CONCLUSIONS AND IMPLICATIONS LPS-mediated formation of the TLR4/MyD88/TRAF6/c-Src complex regulated NF-?B and MAPKs/AP-1 activation leading to VCAM-1 expression and leukocyte adhesion. CORM-2, which liberates CO to elicit direct biological activities, attenuated LPS-induced VCAM-1 expression by interfering with NF-?B and AP-1 activation, and significantly reduced LPS-induced immune cell infiltration of the synovium. PMID:24628691

  4. Pretreatment of lipopolysaccharide (LPS) ameliorates D-GalN/LPS induced acute liver failure through TLR4 signaling pathway.

    PubMed

    Zhang, Sainan; Yang, Naibin; Ni, Shunlan; Li, Wenyuan; Xu, Lanman; Dong, Peihong; Lu, Mingqin

    2014-01-01

    Endotoxin tolerance (ET) is an important phenomenon, which affects inflammation and phagocytosis. Pretreatment with low dose of lipopolysaccharide (LPS) can protect liver injury from various hepatotoxicants such as acetaminophen and pseudomonas aeruginosa exotoxin A. The current study aimed to investigate the protecting mechanisms of endotoxin tolerance in acute liver failure induced by D-galactosamine (D-GalN)/LPS and possible role of toll-like receptors 4 (TLR4) signaling pathway in this phenomenon. Acute liver failure was induced by Injection of D-GalN/LPS. To mimic endotoxin tolerance, male Sprague-Dawley rats were treated with low dose of LPS (0.1 mg/kg once a day intraperitoneally for consecutive five days) before subsequent injection of D-GalN/LPS. Rat survival was determined by survival rate. Liver injury was confirmed by serum biochemical and liver histopathological examination. Inflammatory cytokines were determined by ELISA and nuclear factor-kappa B (NF-?B) (P65), toll-like receptors 4 (TLR4) and Interleukin-1 receptor-associated kinase-1 (IRAK-1) were measured by reverse transcriptase polymerase chain reaction and western blot respectively. Pretreatment of LPS significantly improved rat survival. Moreover, rats pretreated with LPS exhibited lower serum enzyme (ALT, AST and TBiL) level, lower production of inflammatory cytokines and more minor liver histopathological damage than rats without pretreatment of LPS. LPS pretreatment suppressed production of TLR4 and IRAK-1. LPS pretreatment also inhibited activation of hepatic NF-?B. These results indicated that endotoxin tolerance contributed to liver protection against D-GalN/LPS induced acute liver failure through down-regulation of TLR4 and NF-?B pathway. PMID:25400741

  5. Therapeutic Effect of Intravenous Infusion of Perfluorocarbon Emulsion on LPS-Induced Acute Lung Injury in Rats

    PubMed Central

    Lv, Qi; Yin, Xiaofeng; Song, Jianqi; Landén, Ning Xu; Fan, Haojun

    2014-01-01

    Acute lung injury (ALI) and its more severe form, acute respiratory distress syndrome (ARDS) are the leading causes of death in critical care. Despite extensive efforts in research and clinical medicine, mortality remains high in these diseases. Perfluorocarbon (PFC), a chemical compound known as liquid ventilation medium, is capable of dissolving large amounts of physiologically important gases (mainly oxygen and carbon dioxide). In this study we aimed to investigate the effect of intravenous infusion of PFC emulsion on lipopolysaccharide (LPS) induced ALI in rats and elucidate its mechanism of action. Forty two Wistar rats were randomly divided into three groups: 6 rats were treated with saline solution by intratracheal instillation (control group), 18 rats were treated with LPS by intratracheal instillation (LPS group) and the other 18 rats received PFC through femoral vein prior to LPS instillation (LPS+PFC group). The rats in the control group were sacrificed 6 hours later after saline instillation. At 2, 4 and 6 hours of exposure to LPS, 6 rats in the LPS group and 6 rats in LPS+PFC group were sacrificed at each time point. By analyzing pulmonary pathology, partial pressure of oxygen in the blood (PaO2) and lung wet-dry weight ratio (W/D) of each rat, we found that intravenous infusion of PFC significantly alleviated acute lung injury induced by LPS. Moreover, we showed that the expression of pulmonary myeloperoxidase (MPO), intercellular adhesion molecule-1 (ICAM-1) of endothelial cells and CD11b of polymorphonuclear neutrophils (PMN) induced by LPS were significantly decreased by PFC treatment in vivo. Our results indicate that intravenous infusion of PFC inhibits the infiltration of PMNs into lung tissue, which has been shown as the core pathogenesis of ALI/ARDS. Thus, our study provides a theoretical foundation for using intravenous infusion of PFC to prevent and treat ALI/ARDS in clinical practice. PMID:24489970

  6. Pretreatment of lipopolysaccharide (LPS) ameliorates D-GalN/LPS induced acute liver failure through TLR4 signaling pathway

    PubMed Central

    Zhang, Sainan; Yang, Naibin; Ni, Shunlan; Li, Wenyuan; Xu, Lanman; Dong, Peihong; Lu, Mingqin

    2014-01-01

    Endotoxin tolerance (ET) is an important phenomenon, which affects inflammation and phagocytosis. Pretreatment with low dose of lipopolysaccharide (LPS) can protect liver injury from various hepatotoxicants such as acetaminophen and pseudomonas aeruginosa exotoxin A. The current study aimed to investigate the protecting mechanisms of endotoxin tolerance in acute liver failure induced by D-galactosamine (D-GalN)/LPS and possible role of toll-like receptors 4 (TLR4) signaling pathway in this phenomenon. Acute liver failure was induced by Injection of D-GalN/LPS. To mimic endotoxin tolerance, male Sprague-Dawley rats were treated with low dose of LPS (0.1 mg/kg once a day intraperitoneally for consecutive five days) before subsequent injection of D-GalN/LPS. Rat survival was determined by survival rate. Liver injury was confirmed by serum biochemical and liver histopathological examination. Inflammatory cytokines were determined by ELISA and nuclear factor-kappa B (NF-?B) (P65), toll-like receptors 4 (TLR4) and Interleukin-1 receptor-associated kinase-1 (IRAK-1) were measured by reverse transcriptase polymerase chain reaction and western blot respectively. Pretreatment of LPS significantly improved rat survival. Moreover, rats pretreated with LPS exhibited lower serum enzyme (ALT, AST and TBiL) level, lower production of inflammatory cytokines and more minor liver histopathological damage than rats without pretreatment of LPS. LPS pretreatment suppressed production of TLR4 and IRAK-1. LPS pretreatment also inhibited activation of hepatic NF-?B. These results indicated that endotoxin tolerance contributed to liver protection against D-GalN/LPS induced acute liver failure through down-regulation of TLR4 and NF-?B pathway. PMID:25400741

  7. Quercetin 3-O-beta-(2''-galloyl)-glucopyranoside inhibits endotoxin LPS-induced IL-6 expression and NF-kappa B activation in macrophages.

    PubMed

    Kim, Byung Hak; Lee, In Jeong; Lee, Hwa-Young; Han, Sang-Bae; Hong, Jin Tae; Ahn, Byeongwoo; Lee, Chong-Kil; Kim, Youngsoo

    2007-09-01

    We previously isolated quercetin 3-O-beta-(2''-galloyl)-glucopyranoside (QG-32) from Persicaria lapathifolia (Polygonacease) as an inhibitor of superoxide production. In the present study, QG-32 was found to inhibit interleukin (IL)-6 production in endotoxin lipopolysaccharide (LPS)-stimulated macrophages RAW 264.7. The QG-32 attenuated LPS-induced synthesis of IL-6 transcript but also inhibited IL-6 promoter activity, indicating that the compound could down-regulate LPS-induced IL-6 expression at the transcription level. Since nuclear factor (NF)-kappaB has been evidenced to play a major mechanism in the LPS-induced IL-6 expression, an effect of QG-32 on NF-kappaB activating pathway was further analyzed. QG-32 inhibited nuclear import as well as DNA binding activity of NF-kappaB complex and subsequently suppressed NF-kappaB transcriptional activity in LPS-stimulated macrophages. However, QG-32 affected neither LPS-induced inhibitory kappaB (IkappaB) degradation nor IkappaB kinase (IKK) activation. In another experiment, QG-32 inhibited expression vector encoding NF-kappaB p65 or p50-elicited IL-6 promoter activity. Taken together, QG-32 could inhibit NF-kappaB-dependent IL-6 expression, targeting nuclear translocation of NF-kappaB complex downstream IkappaB degradation. This mechanism of action would be different from that of quercetin, an aglycone of QG-32, targeting IKK upstream IkappaB degradation. Finally, this study could provide a pharmacological potential of QG-32 in the inflammatory disorders. PMID:17855110

  8. Anti-inflammatory effect of allylpyrocatechol in LPS-induced macrophages is mediated by suppression of iNOS and COX2 via the NF-?B pathway

    Microsoft Academic Search

    Debjani Sarkar; Piu Saha; Sunita Gamre; Surajit Bhattacharjee; Chellaram Hariharan; Sudipto Ganguly; Rupashree Sen; Goutam Mandal; Subrata Chattopadhyay; Subrata Majumdar; Mitali Chatterjee

    2008-01-01

    The crude ethanol extract of Piper betle leaf is reported to possess anti-inflammatory activity which has been suggested to be mediated by allylpyrocatechol (APC). In the present study, we have demonstrated the anti-inflammatory effects of APC (10 mg\\/kg, p.o.) in an animal model of inflammation. To investigate the mechanism(s) of this anti-inflammatory activity, we examined its effects on the lipopolysaccaride (LPS)-induced

  9. Lipoxin A4 and Platelet Activating Factor Are Involved in E. coli or LPS-Induced Lung Inflammation in CFTR-Deficient Mice

    PubMed Central

    Wu, Haiya; Yang, Jun; Su, Emily M.; Li, Ling; Zhao, Caiqi; Yang, Xi; Gao, Zhaowei; Pan, Mengyao; Sun, Peiyu; Sun, Wei; Jiang, Yiyi; Su, Xiao

    2014-01-01

    CFTR (cystic fibrosis transmembrane conductance regulator) is expressed by both neutrophils and platelets. Lack of functional CFTR could lead to severe lung infection and inflammation. Here, we found that mutation of CFTR (F508del) or inhibition of CFTR in mice led to more severe thrombocytopenia, alveolar neutrocytosis and bacteriosis, and lower lipoxin A4/MIP-2 (macrophage inhibitory protein-2) or lipoxin A4/neutrophil ratios in the BAL (bronchoalveolar lavage) during acute E. coli pneumonia. In vitro, inhibition of CFTR promotes MIP-2 production in LPS-stimulated neutrophils; however, lipoxin A4 could dose-dependently suppress this effect. In LPS-induced acute lung inflammation, blockade of PSGL-1 (P-selectin glycoprotein ligand-1) or P-selectin, antagonism of PAF by WEB2086, or correction of mutated CFTR trafficking by KM11060 could significantly increase plasma lipoxin A4 levels in F508del relevant to wildtype mice. Concurrently, F508del mice had higher plasma platelet activating factor (PAF) levels and PAF-AH activity compared to wildtype under LPS challenge. Inhibiting hydrolysis of PAF by a specific PAF-AH (PAF-acetylhydrolase) inhibitor, MAFP, could worsen LPS-induced lung inflammation in F508del mice compared to vehicle treated F508del group. Particularly, depletion of platelets in F508del mice could significantly decrease plasma lipoxin A4 and PAF-AH activity and deteriorate LPS-induced lung inflammation compared to control F508del mice. Taken together, lipoxin A4 and PAF are involved in E. coli or LPS-induced lung inflammation in CFTR-deficient mice, suggesting that lipoxin A4 and PAF might be therapeutic targets for ameliorating CFTR-deficiency deteriorated lung inflammation. PMID:24671173

  10. iTRAQ proteomic analysis of N-acetylmuramic acid mediated anti-inflammatory capacity in LPS-induced RAW 264.7 cells.

    PubMed

    Wu, Zhen; Pan, Daodong; Guo, Yuxing; Zeng, Xiaoqun; Sun, Yangying

    2015-07-01

    Lactobacillus acidophilus probiotic bacteria have lasting beneficial health effects in the gastrointestinal tract, including protecting against pathogens, improving immunomodulation, and producing beneficial bacteria-derived molecules. In lipopolysaccharide (LPS) induced RAW 264.7 cells treated with peptidoglycan or N-acetylmuramic acid (NAM) from L. acidophilus, 390 differentially expressed proteins (8.76%) were identified by iTRAQ analysis, 257 (5.77%) of which were upregulated and 133 (2.99%) were downregulated under LPS-induced conditions. Most of these proteins were grouped into the following inflammation-related cellular signaling: lysosome pathway, calcium signaling pathway, and Toll-like receptor (TLR) signaling pathway. Among them, clathrin, SERCA, and interleukin 1 receptor antagonist were differentially expressed to a significant degree in peptidoglycan or NAM pretreated RAW 264.7 cells. Bioinformatics analysis indicated that NAM may mediate an anti-inflammatory process via a Ca(2+) -dependent NF-?B pathway. These observations reveal new insights into the molecular mechanisms involved in the suppression of LPS-induced macrophage inflammation by L. acidophilus. PMID:25728578

  11. The influence of temperament on lipopolysaccharide (LPS) induced secretion of epinephrine and cortisol in bulls.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The host's complex reaction to a pathogenic stressor involves interaction of the neural, endocrine, and immune systems. For example, exposure to bacteria stimulates secretion of the stress-related hormones, cortisol (CS) and epinephrine (Epi; 1). Innate and induced secretion of CS and Epi are influe...

  12. Protective effects of dihydroxylphenyl lactic acid and salvianolic acid B on LPS-induced mesenteric microcirculatory disturbance in rats.

    PubMed

    Guo, Jun; Sun, Kai; Wang, Chuan-She; Fang, Su-Ping; Horie, Yoshinori; Yang, Ji-Ying; Liu, Yu-Ying; Wang, Fang; Liu, Lian-Yi; Fan, Jing-Yu; Hibi, Toshifumi; Han, Jing-Yan

    2008-02-01

    Salvia miltiorrhiza is a Chinese medicine widely used for treatment of various cardiovascular diseases. However, little is known about the role of dihydroxylphenyl lactic acid (DLA) and salvianolic acid B (SAB), the main ingredients of S. miltiorrhiza, in the microcirculation. This study aimed to investigate the effect of DLA and SAB on LPS-elicited microcirculatory disturbance, focusing especially on leukocyte adhesion and its potential mechanism. Mesenteric venular diameter, velocity of red blood cells in venules, shear rate of the venular wall, numbers of leukocytes adherent to and emigrated across the venular wall, and mast cell degranulation were determined by an inverted microscope in rats after LPS infusion with or without DLA or SAB. Expression of CD11b and CD18 and production of superoxide anion (*O2-) and hydrogen peroxide (H2O2) by neutrophils were evaluated in vitro by flow cytometry. LPS exposure induced a significant increase in the number of adherent and emigrated leukocytes and mast cell degranulation, and a prominent decrease in the velocity of red blood cells in venules and shear rate of the venular wall. Additionally, in vitro experiments revealed an apparent enhancement in expression of CD11b and CD18 and production of *O2- and H2O2 by rat neutrophils by LPS stimulation. Treatment with DLA or SAB significantly ameliorated LPS-induced microcirculatory disturbance in rat mesentery and inhibited both the expression of CD11b and CD18 and the production of *O2- and H2O2 by neutrophils caused by LPS. PMID:17667359

  13. Gamma-irradiated resveratrol negatively regulates LPS-induced MAPK and NF-?B signaling through TLR4 in macrophages.

    PubMed

    Byun, Eui-Baek; Sung, Nak-Yun; Park, Jae-Nam; Yang, Mi-So; Park, Sang-Hyun; Byun, Eui-Hong

    2015-04-01

    Resveratrol was irradiated at various doses of 15, 30, 50, and 70kGy for the development of physiological functionalities through modification of the structural properties. Gamma irradiation induced a decrease in the resveratrol peak, and the appearance of several new peaks by gamma irradiation was gradually increased up to 70kGy. Gamma-irradiated resveratrol did not exert cytotoxicity to macrophages in dose ranges from 15 to 70kGy; therefore, 70kGy gamma-irradiated resveratrol was used as the maximum dose throughout subsequent experiments. Treatment of LPS-stimulated macrophages with 70kGy gamma-irradiated resveratrol resulted in a dose-dependent decrease in iNOS-mediated NO, PGE2, and pro-inflammatory cytokine level, such as TNF-?, IL-6 and IL-1?. 70kGy gamma-irradiated resveratrol significantly inhibited cyclooxygenase-2 levels, as well as the expression of cell surface molecules, such as CD80 and CD86, in LPS-induced macrophages. Furthermore, the inhibitory action of these pro-inflammatory mediators occurred through an inhibition of MAPKs (ERK1/2, p38 and JNK) and NF-?B signaling pathways based on a toll-like receptor 4 in macrophages, which may be closely mediated with the radiolysis products of resveratrol transformed by gamma-irradiation. From these findings, it seems likely that gamma irradiation can be an effective tool for a reduction of the toxicity and play a potent role in the treatment of inflammatory disease. PMID:25701505

  14. Two structurally distinct {kappa}B sequence motifs cooperatively control LPS-induced KC gene transcription in mouse macrophages

    SciTech Connect

    Ohmori, Y.; Fukumoto, S.; Hamilton, T.A. [Cleveland Clinic Foundation, Cleveland, OH (United States)

    1995-10-01

    The mouse KC gene is an {alpha}-chemokine gene whose transcription is induced in mononuclear phagocytes by LPS. DNA sequences necessary for transcriptional control of KC by LPS were identified in the region flanking the transcription start site. Transient transfection analysis in macrophages using deletion mutants of a 1.5-kb sequence placed in front of the chloramphenicol acetyl transferase (CAT) gene identified an LPS-responsive region between residues -104 and +30. This region contained two {kappa}B sequence motifs. The first motif (position -70 to -59, {kappa}B1) is highly conserved in all three human GRO genes and in the mouse macrophage inflammatory protein-2 (MIP-2) gene. The second {kappa}B motif (position -89 to -78, {kappa}B2) was conserved only between the mouse and the rat KC genes. Consistent with previous reports, the highly conserved {kappa}B site ({kappa}B1) was essential for LPS inducibility. Surprisingly, the distal {kappa}B site ({kappa}B2) was also necessary for optimal response; mutation of either {kappa}B site markedly reduced sensitivity to LPS in RAW264.7 cells and to TNF-{alpha} in NIH 3T3 fibroblasts. Although both {kappa}B1 and {kappa}B2 sequences were able to bind members of the Rel homology family, including NF{kappa}B1 (P50), RelA (65), and c-Rel, the {kappa}B1 site bound these factors with higher affinity and functioned more effectively than the {kappa}B2 site in a heterologous promoter. These findings demonstrate that transcriptional control of the KC gene requires cooperation between two {kappa}B sites and is thus distinct from that of the three human GRO genes and the mouse MIP-2 gene. 71 refs., 8 figs.

  15. Alterations of lung microbiota in a mouse model of LPS-induced lung injury.

    PubMed

    Poroyko, Valeriy; Meng, Fanyong; Meliton, Angelo; Afonyushkin, Taras; Ulanov, Alexander; Semenyuk, Ekaterina; Latif, Omar; Tesic, Vera; Birukova, Anna A; Birukov, Konstantin G

    2015-07-01

    Acute lung injury (ALI) and the more severe acute respiratory distress syndrome are common responses to a variety of infectious and noninfectious insults. We used a mouse model of ALI induced by intratracheal administration of sterile bacterial wall lipopolysaccharide (LPS) to investigate the changes in innate lung microbiota and study microbial community reaction to lung inflammation and barrier dysfunction induced by endotoxin insult. One group of C57BL/6J mice received LPS via intratracheal injection (n = 6), and another received sterile water (n = 7). Bronchoalveolar lavage (BAL) was performed at 72 h after treatment. Bacterial DNA was extracted and used for qPCR and 16S rRNA gene-tag (V3-V4) sequencing (Illumina). The bacterial load in BAL from ALI mice was increased fivefold (P = 0.03). The community complexity remained unchanged (Simpson index, P = 0.7); the Shannon diversity index indicated the increase of community evenness in response to ALI (P = 0.07). Principal coordinate analysis and analysis of similarity (ANOSIM) test (P = 0.005) revealed a significant difference between microbiota of control and ALI groups. Bacteria from families Xanthomonadaceae and Brucellaceae increased their abundance in the ALI group as determined by Metastats test (P < 0.02). In concordance with the 16s-tag data, Stenotrohomonas maltophilia (Xanthomonadaceae) and Ochrobactrum anthropi (Brucellaceae) were isolated from lungs of mice from both groups. Metabolic profiling of BAL detected the presence of bacterial substrates suitable for both isolates. Additionally, microbiota from LPS-treated mice intensified IL-6-induced lung inflammation in naive mice. We conclude that the morbid transformation of ALI microbiota was attributed to the set of inborn opportunistic pathogens thriving in the environment of inflamed lung, rather than the external infectious agents. PMID:25957290

  16. Characterization of LPS-induced TNF? factor (LITAF) from orange-spotted grouper, Epinephelus coioides.

    PubMed

    Cai, Jia; Huang, Youhua; Wei, Shina; Ouyang, Zhengliang; Huang, Xiaohong; Qin, Qiwei

    2013-12-01

    Lipopolysaccharide-induced TNF? factor (LITAF) is an important transcription factor that mediates cell apoptosis and inflammatory response. In the present study, we cloned and characterized a LITAF gene from orange-spotted grouper (Epinephelus coioides) (Ec-LITAF). Ec-LITAF encoded a predicted 142 amino acid protein which shared 74% identity to sablefish (Anoplopoma fimbria) LITAF homolog. Multiple amino acid alignment showed that Ec-LITAF contained a typical LITAF domain with two CXXC motifs. Phylogenetic analysis indicated that Ec-LITAF was closely related to that of sablefish. Ec-LITAF mRNA was widely expressed in different tissues and its expression level in spleen was up-regulated after Singapore grouper iridovirus (SGIV) infection. Subcellular localization analysis revealed that the distribution of Ec-LITAF showed diffuse and aggregated patterns in cytoplasm. Interestingly, the distribution of Ec-LITAF overlayed with a viral LITAF homolog (vLITAF) encoded by SGIV. Overexpression of Ec-LITAF in vitro up-regulated the expression of tumor necrosis factors (TNF1 and TNF2) and TNF receptors (TNFR1 and TNFR2), and the expression of itself initiated apoptosis in fish cells. In addition, overexpression of Ec-LITAF not only accelerated SGIV infection induced CPE and cell death, but also increased viral gene transcription. Taken together, our data suggested that Ec-LITAF might play crucial roles during SGIV replication. PMID:24091064

  17. CD11c+ Alveolar Macrophages are a Source of IL-23 during LPS-induced Acute Lung Injury

    PubMed Central

    Bosmann, Markus; Grailer, Jamison J.; Russkamp, Norman F.; Ruemmler, Robert; Zetoune, Firas S.; Sarma, J. Vidya; Ward, Peter A.

    2013-01-01

    Acute lung injury (ALI) is a severe pulmonary disease causing high numbers of fatalities worldwide. Innate immune responses are an integral part of the pathophysiologic events during ALI. Interleukin-23 (IL-23) is a proinflammatory mediator known to direct the inflammatory responses in various settings of infection, autoimmunity and cancer. IL-23 has been associated with proliferation and effector functions in Th17 cells. Surprisingly, little is known about production of IL-23 during ALI. In this study we found expression of mRNA for IL-23p19 to be 10-fold elevated in lung homogenates of C57BL/6 mice after lipopolysaccharide (LPS)-induced ALI. Likewise, concentrations of IL-23, protein significantly increased in bronchoalveolar lavage fluids. Experiments with IL-23 deficient mice showed that endogenous IL-23 was required for production of IL-17A during LPS-ALI. CD11c-diphtheria toxin receptor transgenic mice were used to selectively deplete CD11c+ cells, the data suggesting that IL-23 production is dependent at least in part on CD11c+ cells during ALI. No alterations of IL-23 levels were observed in Rag-1 deficient mice as compared to wild type C57BL/6 mice following ALI. The mouse alveolar macrophage cell line, MH-S, as well as primary alveolar macrophages displayed abundant surface expression of CD11c. Activation of these macrophages by LPS resulted in release of IL-23 in vitro. Our findings identify CD11c+ macrophages in the lung are likely an important source of IL-23 during ALI, which may be helpful for better understanding of this disease. PMID:23481504

  18. Preferential macrophage recruitment and polarization in LPS-induced animal model for COPD: noninvasive tracking using MRI.

    PubMed

    Al Faraj, Achraf; Sultana Shaik, Asma; Pureza, Mary Angeline; Alnafea, Mohammad; Halwani, Rabih

    2014-01-01

    Noninvasive imaging of macrophages activity has raised increasing interest for diagnosis of chronic obstructive respiratory diseases (COPD), which make them attractive vehicles to deliver contrast agents for diagnostic or drugs for therapeutic purposes. This study was designed to monitor and evaluate the migration of differently polarized M1 and M2 iron labeled macrophage subsets to the lung of a LPS-induced COPD animal model and to assess their polarization state once they have reached the inflammatory sites in the lung after intravenous injection. Ex vivo polarized bone marrow derived M1 or M2 macrophages were first efficiently and safely labeled with amine-modified PEGylated dextran-coated SPIO nanoparticles and without altering their polarization profile. Their biodistribution in abdominal organs and their homing to the site of inflammation in the lung was tracked for the first time using a free-breathing non-invasive MR imaging protocol on a 4.7T magnet after their intravenous administration. This imaging protocol was optimized to allow both detection of iron labeled macrophages and visualization of inflammation in the lung. M1 and M2 macrophages were successfully detected in the lung starting from 2 hours post injection with no variation in their migration profile. Quantification of cytokines release, analysis of surface membrane expression using flow cytometry and immunohistochemistry investigations confirmed the successful recruitment of injected iron labeled macrophages in the lung of COPD mice and revealed that even with a continuum switch in the polarization profile of M1 and M2 macrophages during the time course of inflammation a balanced number of macrophage subsets predominate. PMID:24598763

  19. Preferential Macrophage Recruitment and Polarization in LPS-Induced Animal Model for COPD: Noninvasive Tracking Using MRI

    PubMed Central

    Al Faraj, Achraf; Sultana Shaik, Asma; Pureza, Mary Angeline; Alnafea, Mohammad; Halwani, Rabih

    2014-01-01

    Noninvasive imaging of macrophages activity has raised increasing interest for diagnosis of chronic obstructive respiratory diseases (COPD), which make them attractive vehicles to deliver contrast agents for diagnostic or drugs for therapeutic purposes. This study was designed to monitor and evaluate the migration of differently polarized M1 and M2 iron labeled macrophage subsets to the lung of a LPS-induced COPD animal model and to assess their polarization state once they have reached the inflammatory sites in the lung after intravenous injection. Ex vivo polarized bone marrow derived M1 or M2 macrophages were first efficiently and safely labeled with amine-modified PEGylated dextran-coated SPIO nanoparticles and without altering their polarization profile. Their biodistribution in abdominal organs and their homing to the site of inflammation in the lung was tracked for the first time using a free-breathing non-invasive MR imaging protocol on a 4.7T magnet after their intravenous administration. This imaging protocol was optimized to allow both detection of iron labeled macrophages and visualization of inflammation in the lung. M1 and M2 macrophages were successfully detected in the lung starting from 2 hours post injection with no variation in their migration profile. Quantification of cytokines release, analysis of surface membrane expression using flow cytometry and immunohistochemistry investigations confirmed the successful recruitment of injected iron labeled macrophages in the lung of COPD mice and revealed that even with a continuum switch in the polarization profile of M1 and M2 macrophages during the time course of inflammation a balanced number of macrophage subsets predominate. PMID:24598763

  20. Influence of Synthetic Antiendotoxin Peptides on Lipopolysaccharide (LPS) Recognition and LPS-Induced Proinflammatory Cytokine Responses by Cells Expressing Membrane-Bound CD14

    PubMed Central

    Iwagaki, Akitaka; Porro, Massimo; Pollack, Matthew

    2000-01-01

    Lipopolysaccharides (LPS) are proinflammatory bacterial products implicated in the pathogenesis of gram-negative sepsis and septic shock. Polymyxin B (PMB), a cyclic, cationic peptide antibiotic, inhibits biological activities of LPS through high-affinity binding to the lipid A moiety. Small synthetic peptides have been designed to mimic the primary and secondary structures of PMB to determine structural requirements for binding and detoxification of lipid A and to assess possible therapeutic potential. The purpose of this study was to compare and contrast the endotoxin-neutralizing activities of two synthetic antiendotoxin peptides (SAEP-2 and SAEP-4), PMB, and an LPS core-specific monoclonal antibody (MAb), WN1 222-5, based on their abilities to inhibit CD14-mediated target cell uptake of fluorescein isothiocyanate (FITC)-conjugated LPS, detected by flow cytometry and confocal microscopy, and LPS-induced production of the proinflammatory cytokines, interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-?), as measured by bioassays. PMB and SAEP-4 produced dose-dependent inhibition of FITC-LPS uptake by CD14-transfected Chinese hamster ovary fibroblasts (CHO-CD14 cells) and by human peripheral blood mononuclear cells. The anti-LPS MAb, WN1 222-5, also blocked LPS uptake by these cells and synergized with PMB and SAEP-4. LPS-induced IL-6 release was inhibited by PMB, SAEP-4, and MAb WN1 222-5, and these inhibitory activities were additive or synergistic. LPS-induced TNF-? release by PBMC was also inhibited by PMB and SAEP-4 alone and in combination with anti-LPS MAb. SAEP-2, in contrast, produced comparatively minor decrements in cellular uptake of LPS and LPS-induced cytokine responses, and did so only in the absence of serum, while a nonsense peptide exerted no discernible inhibitory effect on LPS uptake or LPS-induced cytokine expression in the presence or absence of serum. Thus, PMB and SAEP-4, like the LPS-reactive MAb, WN1 222-5, block proinflammatory activities of LPS in part by preventing LPS recognition by membrane-bound CD14-expressing target cells. Differences in peptide structure, however, like those exemplified by SAEP-2 and SAEP-4, may differentially affect the endotoxin-neutralizing potency of these peptides despite similar binding activity against lipid A, reflecting possible differences in peptide solubility or peptide regulation of intracellular signal transduction. PMID:10678985

  1. Cocaine counteracts LPS-induced hypolocomotion and triggers locomotor sensitization expression.

    PubMed

    Tortorelli, Lucas Silva; Engelke, Douglas Senna; Lunardi, Paula; Mello E Souza, Tadeu; Santos-Junior, Jair Guilherme; Gonçalves, Carlos-Alberto

    2015-07-01

    Neuroimmune signalling underlies addiction and comorbid depression. Clinical observations indicate that infections and chronic lesions are more frequent in drug users and elevated inflammatory states are evident in cocaine dependents. Therefore, lipopolysaccharide (LPS) and inflammatory cytokines represent an important tool for the investigation of sickness, depressive illness and addiction behaviour. A major component of addiction is the progressive and persistent increase in locomotor activity after repeated drug administration and even prolonged periods of abstinence. The aim of this study was to investigate the response of locomotor sensitization when a non-sensitizing dose of cocaine is paired with a systemic inflammatory stimulus. LPS and cocaine were administered intraperitonealy in young-adult male C57bl/6 mice during a 5-day acquisition phase. After a 48-h withdrawal period all groups were challenged with cocaine to evaluate locomotor expression. During the acquisition phase, the LPS-treated groups displayed characteristic hypolocomotion related to sickness behaviour. The low dose of cocaine did not increase the distance travelled, characterizing a non-sensitization dose. Groups that received both LPS and cocaine did not display hypolocomotion, indicating that cocaine might counteract hypolocomotion sickness behaviour. Moreover, during challenge, only these animals expressed locomotor sensitization. Our results indicate that LPS could facilitate the expression of locomotor sensitization in mice and that the immune system may modulate cocaine-induced sensitization. PMID:25835320

  2. Genomic Instability in Liver Cells Caused by an LPS-Induced Bystander-Like Effect

    PubMed Central

    Kovalchuk, Igor; Walz, Paul; Thomas, James; Kovalchuk, Olga

    2013-01-01

    Bacterial infection has been linked to carcinogenesis, however, there is lack of knowledge of molecular mechanisms that associate infection with the development of cancer. We analyzed possible effects of the consumption of heat-killed E. coli O157:H7 cells or its cellular components, DNA, RNA, protein or lipopolysaccharides (LPS) on gene expression in naïve liver cells. Four week old mice were provided water supplemented with whole heat-killed bacteria or bacterial components for a two week period. One group of animals was sacrificed immediately, whereas another group was allowed to consume uncontaminated tap water for an additional two weeks, and liver samples were collected, post mortem. Liver cells responded to exposure of whole heat-killed bacteria and LPS with alteration in ?H2AX levels and levels of proteins involved in proliferation, DNA methylation (MeCP2, DNMT1, DNMT3A and 3B) or DNA repair (APE1 and KU70) as well as with changes in the expression of genes involved in stress response, cell cycle control and bile acid biosynthesis. Other bacterial components analysed in this study did not lead to any significant changes in the tested molecular parameters. This study suggests that lipopolysaccharides are a major component of Gram-negative bacteria that induce molecular changes within naïve cells of the host. PMID:23874414

  3. Genomic instability in liver cells caused by an LPS-induced bystander-like effect.

    PubMed

    Kovalchuk, Igor; Walz, Paul; Thomas, James; Kovalchuk, Olga

    2013-01-01

    Bacterial infection has been linked to carcinogenesis, however, there is lack of knowledge of molecular mechanisms that associate infection with the development of cancer. We analyzed possible effects of the consumption of heat-killed E. coli O157:H7 cells or its cellular components, DNA, RNA, protein or lipopolysaccharides (LPS) on gene expression in naïve liver cells. Four week old mice were provided water supplemented with whole heat-killed bacteria or bacterial components for a two week period. One group of animals was sacrificed immediately, whereas another group was allowed to consume uncontaminated tap water for an additional two weeks, and liver samples were collected, post mortem. Liver cells responded to exposure of whole heat-killed bacteria and LPS with alteration in ?H2AX levels and levels of proteins involved in proliferation, DNA methylation (MeCP2, DNMT1, DNMT3A and 3B) or DNA repair (APE1 and KU70) as well as with changes in the expression of genes involved in stress response, cell cycle control and bile acid biosynthesis. Other bacterial components analysed in this study did not lead to any significant changes in the tested molecular parameters. This study suggests that lipopolysaccharides are a major component of Gram-negative bacteria that induce molecular changes within naïve cells of the host. PMID:23874414

  4. LPS-inducible factor(s) from activated macrophages mediates cytolysis of Naegleria fowleri amoebae

    SciTech Connect

    Cleary, S.F.; Marciano-Cabral, F.

    1986-03-01

    Soluble cytolytic factors of macrophage origin have previously been described with respect to their tumoricidal activity. The purpose of this study was to investigate the mechanism and possible factor(s) responsible for cytolysis of the amoeba Naegleria fowleri by activated peritoneal macrophages from B6C3F1 mice. Macrophages or conditioned medium (CM) from macrophage cultures were incubated with /sup 3/H-Uridine labeled amoebae. Percent specific release of label served as an index of cytolysis. Bacille Calmette-Guerin (BCG) and Corynebacterium parvum macrophages demonstrated significant cytolysis of amoebae at 24 h with an effector to target ratio of 10:1. Treatment of macrophages with inhibitors of RNA or protein synthesis blocked amoebicidal activity. Interposition of a 1 ..mu..m pore membrane between macrophages and amoebae inhibited killing. Inhibition in the presence of the membrane was overcome by stimulating the macrophages with LPS. CM from SPS-stimulated, but not unstimulated, cultures of activated macrophages was cytotoxic for amoebae. The activity was heat sensitive and was recovered from ammonium sulfate precipitation of the CM. Results indicate that amoebicidal activity is mediated by a protein(s) of macrophage origin induced by target cell contact or stimulation with LPS.

  5. Epidural analgesia with morphine or buprenorphine in ponies with lipopolysaccharide (LPS)-induced carpal synovitis

    PubMed Central

    Freitas, Gabrielle C.; Carregaro, Adriano B.; Gehrcke, Martielo I.; De La Côrte, Flávio D.; Lara, Valéria M.; Pozzobon, Ricardo; Brass, Karin E.

    2011-01-01

    This study evaluated the analgesia effects of the epidural administration of 0.1 mg/kg bodyweight (BW) of morphine or 5 ?g/kg BW of buprenorphine in ponies with radiocarpal joint synovitis. Six ponies were submitted to 3 epidural treatments: the control group (C) received 0.15 mL/kg BW of a 0.9% sodium chloride (NaCl) solution; group M was administered 0.1 mg/kg BW of morphine; and group B was administered 5 ?g/kg BW of buprenorphine, both diluted in 0.9% NaCl to a total volume of 0.15 mL/kg BW administered epidurally at 10 s/mL. The synovitis model was induced by injecting 0.5 ng of lipopolysaccharide (LPS) in the left or right radiocarpal joint. An epidural catheter was later introduced in the lumbosacral space and advanced up to the thoracolumbar level. The treatment started 6 h after synovitis induction. Lameness, maximum angle of carpal flexion, heart rate, systolic arterial pressure, respiratory rate, temperature, and intestinal motility were evaluated before LPS injection (baseline), 6 h after LPS injection (time 0), and 0.5, 1, 2, 4, 6, 8, 10, 12, 16, 20, and 24 h after treatments. Although the model of synovitis produced clear clinical signs of inflammation, the lameness scores in group C were different from the baseline for only up to 12 h. Both morphine and buprenorphine showed a reduction in the degree of lameness starting at 0.5 and 6 h, respectively. Reduced intestinal motility was observed at 0.5 h in group M and at 0.5 to 1 h in group B. Epidural morphine was a more effective analgesic that lasted for more than 12 h and without side effects. It was concluded that morphine would be a valuable analgesic option to alleviate joint pain in the thoracic limbs in ponies. PMID:21731186

  6. Pharmacological inhibition of GSK-3 in a guinea pig model of LPS-induced pulmonary inflammation: II. Effects on skeletal muscle atrophy

    PubMed Central

    2013-01-01

    Background Chronic obstructive pulmonary disease (COPD) is accompanied by pulmonary inflammation and associated with extra-pulmonary manifestations, including skeletal muscle atrophy. Glycogen synthase kinase-3 (GSK-3) has been implicated in the regulation of muscle protein- and myonuclear turnover; two crucial processes that determine muscle mass. In the present study we investigated the effect of the selective GSK-3 inhibitor SB216763 on muscle mass in a guinea pig model of lipopolysaccharide (LPS)-induced pulmonary inflammation-associated muscle atrophy. Methods Guinea pigs were pretreated with either intranasally instilled SB216763 or corresponding vehicle prior to each LPS/saline challenge twice weekly. Pulmonary inflammation was confirmed and indices of muscle mass were determined after 12 weeks. Additionally, cultured skeletal muscle cells were incubated with tumor necrosis factor ? (TNF-?) or glucocorticoids (GCs) to model the systemic effects of pulmonary inflammation on myogenesis, in the presence or absence of GSK-3 inhibitors. Results Repeated LPS instillation induced muscle atrophy based on muscle weight and muscle fiber cross sectional area. Intriguingly, GSK-3 inhibition using SB216763 prevented the LPS-induced muscle mass decreases and myofiber atrophy. Indices of protein turnover signaling were unaltered in guinea pig muscle. Interestingly, inhibition of myogenesis of cultured muscle cells by TNF-? or synthetic GCs was prevented by GSK-3 inhibitors. Conclusions In a guinea pig model of LPS-induced pulmonary inflammation, GSK-3 inhibition prevents skeletal muscle atrophy without affecting pulmonary inflammation. Resistance to inflammation- or GC-induced impairment of myogenic differentiation, imposed by GSK-3 inhibition, suggests that sustained myogenesis may contribute to muscle mass maintenance despite persistent pulmonary inflammation. Collectively, these results warrant further exploration of GSK-3 as a potential novel drug target to prevent or reverse muscle wasting in COPD. PMID:24180420

  7. Selected contribution: role of IL-6 in LPS-induced nuclear STAT3 translocation in sensory circumventricular organs during fever in rats.

    PubMed

    Harré, Eva-Maria; Roth, Joachim; Pehl, Ulrich; Kueth, Matthias; Gerstberger, Rüdiger; Hübschle, Thomas

    2002-06-01

    Interleukin-6 (IL-6) is regarded as an endogenous mediator of lipopolysaccharide (LPS)-induced fever. IL-6 is thought to act on the brain at sites that lack a blood-brain barrier, the circumventricular organs (CVOs). Cells that are activated by IL-6 respond with nuclear translocation of the signal transducer and activator of transcription 3 molecule (STAT3) and can be detected by immunohistochemistry. We investigated whether the LPS-induced release of IL-6 into the systemic circulation was accompanied by a nuclear STAT3 translocation within the sensory CVOs. Treatment with LPS (100 microg/kg) led to a slight (1 h) and then a strong increase (2-8 h) in plasma IL-6 levels, which started to decline at the end of the febrile response. Administration of both pyrogens LPS and IL-6 (45 microg/kg) induced a febrile response with IL-6, causing a rather moderate fever compared with the LPS-induced fever. Nuclear STAT3 translocation in response to LPS was observed within the vascular organ of the lamina terminalis (OVLT) and the subfornical organ (SFO) 2 h after LPS treatment. To investigate whether this effect was mediated by IL-6, the cytokine itself was systemically applied and indeed an identical pattern of nuclear STAT3 translocation was observed. However, nuclear STAT3 translocation already occurred 1 h after IL-6 application and proved to be less effective compared with LPS treatment when analyzing OVLT and SFO cell numbers that showed nuclear STAT3 immunoreactivity after the respective pyrogen treatment. Our observations represent the first molecular evidence for an IL-6-induced STAT3-mediated genomic activation of OVLT and SFO cells and support the proposed role of these brain areas as sensory structures for humoral signals created by the activated immune system and resulting in the generation of fever. PMID:12015387

  8. Aqueous Extract of Gracilaria tenuistipitata Suppresses LPS-Induced NF-?B and MAPK Activation in RAW 264.7 and Rat Peritoneal Macrophages and Exerts Hepatoprotective Effects on Carbon Tetrachloride-Treated Rat

    PubMed Central

    Tseng, Chin-Kai; Lin, Chun-Kuang; Chang, Hsueh-Wei; Wu, Yu-Hsuan; Yen, Feng-Lin; Chang, Fang-Rong; Chen, Wei-Chun; Yeh, Chi-Chen; Lee, Jin-Ching

    2014-01-01

    In addition to the previous investigations of bioactivity of aqueous extract of the edible Gracilaria tenuistipitata (AEGT) against H2O2-induced DNA damage and hepatitis C virus replication, the purpose of this study is to evaluate the potential therapeutic properties of AEGT against inflammation and hepatotoxicity using lipopolysaccharide (LPS)-stimulated mouse RAW 264.7 cells, primary rat peritoneal macrophages and carbon tetrachloride (CCl4)-induced acute hepatitis model in rats. AEGT concentration-dependently inhibited the elevated RNA and protein levels of inducible nitric oxide synthase and cyclooxygenase-2, thereby reducing nitric oxide and prostaglandin E2 levels, respectively. Moreover, AEGT significantly suppressed the production of LPS-induced proinflammatory cytokines, including interleukin (IL)-1?, IL-6 and tumor necrosis factor-?. These inhibitory effects were associated with the suppression of nuclear factor-kappa B activation and mitogen-activated protein kinase phosphorylation by AEGT in LPS-stimulated cells. In addition, we highlighted the hepatoprotective and curative effects of AEGT in a rat model of CCl4-intoxicated acute liver injury, which was evident from reduction in the elevated serum aspartate aminotransferase and alanine aminotransferase levels as well as amelioration of histological damage by pre-treatment or post-treatment of AEGT. In conclusion, the results demonstrate that AEGT may serve as a potential supplement in the prevention or amelioration of inflammatory diseases. PMID:24475143

  9. Mechanism of anti-inflammatory effect of tricin, a flavonoid isolated from Njavara rice bran in LPS induced hPBMCs and carrageenan induced rats.

    PubMed

    Shalini, V; Jayalekshmi, Ananthasankaran; Helen, A

    2015-08-01

    Njavara is an indigenous medicinal rice variety traditionally used in Ayurvedic system of medicine practiced in Kerala, India. Tricin is a bioflavonoid present in significantly higher levels in rice bran of Njavara. Present study attempted to identify the molecular target of tricin in TLR mediated signaling pathways by using lipopolysaccharide (LPS) induced human peripheral blood mononuclear cells (hPBMCs) and carrageenan induced paw edema in rats as experimental models. Tricin acted upstream in the activation of inflammation cascade by interfering with TLR4 activation, preferably by blocking the LPS induced activation of TLR4, MYD88 and TRIF proteins in hPBMCs. Subsequently, tricin significantly blocked the activation of downstream kinases like p38MAPK, JNK1/2 and IRF3. Thus the inhibitory effect of tricin on NF-?B and IRF3 together confirms the specific inhibition of both MYD88 dependent and TRIF dependent pathways. Tricin treatment also inhibited the pro-inflammatory effect of LPS by blocking the TLR4 signaling mediated activation of cytosolic phospholipase A2 (cPLA2), which is confirmed by specific inhibition of COX-2. Results demonstrated that in addition to NF-?B, tricin can prevent the activation of STAT proteins by significantly inhibiting the activation of both STAT1 and STAT3 via the down regulation of upstream phosphorylating enzymes like JAK1 and JAK2. The protective anti-inflammatory effect of tricin was also confirmed by in vivo experiments. Thus, this study provides strong evidence that tricin exerts its anti-inflammatory effect via a mechanism involving the TLR4/NF-?B/STAT signaling cascade. PMID:25839778

  10. Oxymatrine lightened the inflammatory response of LPS-induced mastitis in mice through affecting NF-?B and MAPKs signaling pathways.

    PubMed

    Yang, Zhengtao; Yin, Ronglan; Cong, Yunfeng; Yang, Zhanqing; Zhou, Ershun; Wei, Zhengkai; Liu, Zhicheng; Cao, Yongguo; Zhang, Naisheng

    2014-12-01

    Mastitis, an inflammatory reaction of the mammary gland, is recognized as one of the most costly diseases in dairy cattle. Oxymatrine, one of the alkaloids extracted from Chinese herb Sophora flavescens Ait, has been reported to have many biological activities, such as anti-inflammatory, anti-virus, and anti-hepatic fibrosis properties. The aim of this study was to investigate the protective effect and the anti-inflammatory mechanism of oxymatrine on lipopolysaccharide (LPS)-induced mastitis in mice. The mouse mastitis was induced by 10 ?g of LPS for 24 h. Oxymatrine was intraperitoneally administered with the dose of 30, 60, and 120 mg/kg 1 h before and 12 h after LPS induction. The results showed that oxymatrine significantly attenuated the damage of the mammary gland induced by LPS. Oxymatrine inhibited the phosphorylation of NF-?B p65 and I?B in NF-?B signal pathway and reduced the phosphorylation of p38, ERK, and JNK in mitogen-activated protein kinase (MAPKs) signal pathway. The results showed that oxymatrine had a protective effect on LPS-induced mastitis, and the anti-inflammatory mechanism of oxymatrine was related to the inhibition of NF-?B and MAPKs signal pathways. PMID:25034832

  11. Terminalia chebula extract protects OGD-R induced PC12 cell death and inhibits lps induced microglia activation.

    PubMed

    Gaire, Bhakta Prasad; Jamarkattel-Pandit, Nirmala; Lee, Donghun; Song, Jungbin; Kim, Ji Young; Park, Juyeon; Jung, Soyoung; Choi, Ho-Young; Kim, Hocheol

    2013-01-01

    Terminalia chebula, native to Southeast Asia, is a popular medicinal plant in Ayurveda. It has been previously reported to have strong antioxidant and anti-inflammatory efficacy. In this study, we aimed to investigate if fruit extract from T. chebula might protect neuronal cells against ischemia and related diseases by reduction of oxidative damage and inflammation in rat pheochromocytoma cells (PC12) using in vitro oxygen-glucose deprivation followed by reoxygenation (OGD-R) ischemia and hydrogen peroxide (H2O2) induced cell death. Cell survival was evaluated by a 2-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Free radical scavenging, lipid peroxidation and nitric oxide inhibition were measured by diphenyl-1-picrylhydrazyl (DPPH), thiobarbituric acid (TBA) and Griess reagent, respectively. We found that T. chebula extract: (1) increases the survival of cells subjected to OGD-R by 68%, and H2O2 by 91.4%; (2) scavenges the DPPH free radical by 96% and decreases malondialdehyde (MDA) levels from 237.0 ± 15.2% to 93.7 ± 2.2%; (3) reduces NO production and death rate of microglia cells stimulated by lipopolysaccharide (LPS). These results suggest that T. chebula extract has the potential as a natural herbal medicine, to protect the cells from ischemic damage and the possible mechanism might be the inhibition of oxidative and inflammatory processes. PMID:23519197

  12. Cancer-derived immunoglobulin G promotes LPS-induced proinflammatory cytokine production via binding to TLR4 in cervical cancer cells

    PubMed Central

    Peng, Hui; Shao, Jimin; Gu, Jiang

    2014-01-01

    Numerous studies have shown that various cancer cells express immunoglobulin G (IgG). However, the function of cancer-derived IgG and the underlying mechanism remain unclear. In this study, we demonstrated that IgG expression was significantly altered after exposure to LPS in cervical cancer cells, suggesting that IgG was potentially involved in regulation of TLR4 signaling. Reduction of IgG attenuated LPS-induced proinflammatory cytokine production. The phosphorylation levels of NF-?B and MAPK were consistently suppressed by knockdown of IgG, which in turn impaired NF-?B nuclear translocation and the activity of NF-?B responsive element. Furthermore, we found that IgG was recruited to TLR4 in the cytoplasm after LPS stimulation, and IgG silencing inhibited LPS-initiated proinflammatory cytokine production through downregulating TLR4 expression. Similar results were obtained in a mouse model of endotoxemia and human tissues. Taken together, our findings demonstrate that IgG is a positive regulator of LPS-induced proinflammatory cytokine production by binding to TLR4 and enhancing its expression. TLR4 signaling plays a positive role in the development of many inflammation induced cancers such as cervical cancer. Our study strongly indicates that IgG may promote cervical cancer cell proliferation through enhancing TLR4 signaling. IgG may be a novel therapeutic target in treating inflammation mediated cancers. PMID:25179302

  13. CD200R1 agonist attenuates LPS-induced inflammatory response in human renal proximal tubular epithelial cells by regulating TLR4-MyD88-TAK1-mediated NF-?B and MAPK pathway.

    PubMed

    Ding, Yan; Yang, Huilan; Xiang, Wei; He, Xiaojie; Liao, Wang; Yi, Zhuwen

    2015-05-01

    Previous studies have revealed the anti-inflammatory effect of CD200Fc, an agonist of CD200R1 in autoimmune disease. However, little is known about its anti-inflammatory effects in kidney diseases. The aim of this study is to assess the function of CD200Fc in regulating lipopolysaccharide (LPS)-induced inflammatory response in human renal proximal tubular epithelial cells (hRPTECs) and the possible mechanisms. LPS reduced the CD200R1 expression in hRPTECs, and this effect was attenuated by CD200Fc in a dose-dependent manner. In addition, CD200Fc inhibited LPS-induced expressions of TLR4 and its adapter molecule (MyD88 and phosphorylation of TAK1), and abolished its interactions with MyD88 or TAK1 in hRPTECs cells. CD200Fc also attenuated LPS-induced phosphorylation of I?B, NF-?B-P65 translocation to nucleus, and increased phosphorylation of ERK1/2, p38 and JNK in hRPTECs. Moreover, CD200Fc suppressed the LPS-induced release of pro-inflammatory mediators in hRPTECs, including IL-1?, IL-6, IL-8, MCP-1, VCAM-1, ICAM-1, TNF-?, INF-? and INF-?. Our results suggested that CD200Fc could inhibit the TLR4-mediated inflammatory response in LPS-induced hRPTECs, thus might be beneficial for the treatment of renal disease, such as lupus nephritis. PMID:25791482

  14. Spin Trapping Agent, Phenyl N- tertbutyl Nitrone (PBN) Inhibits Induction of Nitric Oxide Synthase in Endotoxin-Induced Shock in Mice

    Microsoft Academic Search

    T. Miyajima; Y. Kotake

    1995-01-01

    Spin trapping agent, phenyl N-tert-butyl nitrone (PBN) significantly reduces mortality due to lipopolysaccharide (LPS)-induced shock in Balb\\/c mice as had previously been shown in rats. We hypothesized that PBN decreases mortality by directly or indirectly inhibiting nitric oxide (NO) generation. Therefore, we determined the effect of PBN administration on LPS-induced NO generation in mice. NO generation was monitored in the

  15. Theaflavin Inhibits LPS-Induced IL-6, MCP-1, and ICAM-1 Expression in Bone Marrow-Derived Macrophages Through the Blockade of NF-?B and MAPK Signaling Pathways

    PubMed Central

    Kim, Seewan

    2011-01-01

    Theaflavin, the main polyphenol in black tea, has anti-inflammatory, antioxidative, anti-mutagenic, and anti-carcinogenic properties. The aim of this study was to evaluate the effects of theaflavin on lipopolysaccharide (LPS)-induced innate signaling and expression of pro-inflammatory mediators in bone marrow-derived macrophages isolated from ICR mice. The effects of theaflavin on the expression of proinflammatory mediators, LPS-induced nuclear factor-kappa B (NF-?B), and mitogen-activated protein kinase (MAPK) signaling pathways were examined by reverse transcriptase-polymerase chain reaction (RT-PCR), Western blotting, and immunofluorescence. LPS-induced interleukin-6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), and intercellular adhesion molecule-1 (ICAM-1) expression was inhibited by theaflavin. LPS-induced inhibitor kappa B alpha (I?B?) degradation and nuclear translocation of RelA were blocked by theaflavin. LPS-induced phosphorylation of extracellular signal-regulated kinase1/2 (ERK1/2), c-Jun-N-terminal kinase (JNK), and p38 MAPK was inhibited by theaflavin. The inhibitory effect of theaflavin on IL-6, MCP-1, and ICAM-1 expression was completely inhibited by Bay11-7082 (NF-?B inhibitor). The inhibitory effect of theaflavin on IL-6 and ICAM-1 expression was inhibited by SB203580 (p38 MAPK inhibitor). The inhibitory effect of theaflavin on MCP-1 expression was inhibited by SP600125 (JNK inhibitor). These results indicate that theaflavin prevents LPS-induced IL-6, MCP-1, and ICAM-1 expression through blockade of NF-?B and MAPK signaling pathways in bone marrow-derived macrophages. PMID:22111069

  16. The inhibitory effects of Geranium thunbergii on interferon-?- and LPS-induced inflammatory responses are mediated by Nrf2 activation

    PubMed Central

    CHOI, HEE-JIN; CHOI, HEE-JUNG; PARK, MI-JU; LEE, JI-YEON; JEONG, SEUNG-IL; LEE, SEONGOO; KIM, KYUN HA; JOO, MYUNGSOO; JEONG, HAN-SOL; KIM, JAI-EUN; HA, KI-TAE

    2015-01-01

    Geranium thunbergii Sieb. et Zucc. (GT; which belongs to the Geraniaceae family) has been used as a traditional medicine in East Asia for the treatment of inflammatory diseases, including arthritis and diarrhea. However, the underlying mechanisms of the anti-inflammatory effects of GT remain poorly understood. In the present study, we examined the mechanisms responsible for the anti-inflammatory activity of GT in macrophages. The results revealed that GT significantly inhibited the lipopolysaccharide (LPS)- and interferon-? (IFN-?)-induced expression of pro-inflammatory genes, such as inducible nitric oxide synthase, tumor necrosis factor-? and interleukin-1?, as shown by RT-PCR. However, the inhibitory effects of GT on LPS- and IFN-?-induced inflammation were associated with an enhanced nuclear factor erythroid 2-related factor 2 (Nrf2) activity, but not with the suppression of nuclear factor (NF)-?B activity, as shown by western blot analysis. In addition, in bone marrow-derived macrophages (BMDM) isolated from Nrf2 knockout mice, GT did not exert any inhibitory effect on the LPS- and IFN-?-induced inflammation. Taken together, our findings indicate that the anti-inflammatory effects of GT may be associated with the activation of Nrf2, an anti-inflammatory transcription factor. PMID:25761198

  17. Synthetic wogonin derivatives suppress lipopolysaccharide-induced nitric oxide production and hydrogen peroxide-induced cytotoxicity

    Microsoft Academic Search

    Wanjoo Chun; Hee Jae Lee; Pil-Jae Kong; Gun Hee Lee; ll-Young Cheongsu; Sung-Soo Kim

    2005-01-01

    Wogonin (5,7-dihydroxy-8-methoxyflavone) has been reported to exhibit a variety of biological properties including anti-inflammatory\\u000a and neuroprotective functions. In this study, biological activities of diverse synthetic wogonin derivatives have been evaluated\\u000a in two experimental cell culture models. Inhibitory activities of wogonin derivatives on lipopolysaccharide (LPS)-induced\\u000a nitric oxide (NO) production in BV2 microglial cells and on hydrogen peroxide (H202)-induced neuronal cell death

  18. The Anti-inflammatory Effect of the CXCR4 Antagonist-N15P Peptide and Its Modulation on Inflammation-Associated Mediators in LPS-Induced PBMC.

    PubMed

    Xue-Mei, Mo; Han-Xiao, Sun

    2015-06-01

    Inflammation was the important pathological process of many disease developments, but current therapeutic means for inflammatory diseases are not satisfactory. Chemokines and their receptors represent valuable targets for anti-inflammatory drug discovery. The N15P polypeptide (sequence: LGASWHRPDKCCLGY) is independently developed by our research group, it is a new CXCR4 antagonist drug derived from viral macrophage inflammatory protein-II (vMIP-II). This study aims to clarify the anti-inflammatory potency of N15P polypeptide on the lipopolysaccharide (LPS)-induced inflammation in vitro. In this study, we evaluated the anti-inflammatory effects of N15P polypeptide by the LPS-induced peripheral blood mononuclear cell (PBMC) model and measured the level of inflammatory factors (tumor necrosis factor alpha (TNF-?), IL-6, IL-8, nuclear factor kappaB (NF-?B), cyclooxygenase-2 (COX-2), Toll-like receptor 4 (TLR4), MyD88, phosphoinositide 3-kinase (PI3K), and Akt). The messenger RNA (mRNA) expressions of inflammatory factors were analyzed by real-time PCR (RT-PCR) microarray analysis, and the production of inflammatory factors was measured further by enzyme-linked immunosorbent assay (ELISA) and Western blot. The results showed that the expression of inflammatory factors (TNF-?, IL-6, IL-8, NF-?B, COX-2, TLR4, MyD88, PI3K, and Akt) was downregulated by N15P peptide, suggesting that N15P peptide has a strong inhibitory effect on the inflammatory responses induced by LPS. PMID:25676435

  19. Microarray analyses of the effects of NF-kappaB or PI3K pathway inhibitors on the LPS-induced gene expression profile in RAW264.7 cells: synergistic effects of rapamycin on LPS-induced MMP9-overexpression.

    PubMed

    Mendes, Sofia Dos Santos; Candi, Aurélie; Vansteenbrugge, Martine; Pignon, Marie-Rose; Bult, Hidde; Boudjeltia, Karim Zouaoui; Munaut, Carine; Raes, Martine

    2009-07-01

    Lipopolysaccharide (LPS) activates a broad range of signalling pathways including mainly NF-kappaB and the MAPK cascade, but recent evidence suggests that LPS stimulation also activates the PI3K pathway. To unravel the specific roles of both pathways in LPS signalling and gene expression profiling, we investigated the effects of different inhibitors of NF-kappaB (BAY 11-7082), PI3K (wortmannin and LY294002) but also of mTOR (rapamycin), a kinase acting downstream of PI3K/Akt, in LPS-stimulated RAW264.7 macrophages, analyzing their effects on the LPS-induced gene expression profile using a low density DNA microarray designed to monitor the expression of pro-inflammatory genes. After statistical and hierarchical cluster analyses, we determined five clusters of genes differentially affected by the four inhibitors used. In the fifth cluster corresponding to genes upregulated by LPS and mainly affected by BAY 11-7082, the gene encoding MMP9 displayed a particular expression profile, since rapamycin drastically enhanced the LPS-induced upregulation at both the mRNA and protein levels. Rapamycin also enhanced the LPS-induced NF-kappaB transactivation as determined by a reporter assay, phosphorylation of the p38 and Erk1/2 MAPKs, and counteracted PPAR activity. These results suggest that mTOR could negatively regulate the effects of LPS on the NF-kappaB and MAPK pathways. We also performed real-time RT-PCR assays on mmp9 expression using rosiglitazone (agonist of PPARgamma), PD98059 (inhibitor of Erk 1/2) and SB203580 (inhibitor of p38(MAPK)), that were able to counteract the rapamycin mediated overexpression of mmp9 in response to LPS. Our results suggest a new pathway involving mTOR for regulating specifically mmp9 in LPS-stimulated RAW264.7 cells. PMID:19285553

  20. Targeting the annexin 1-formyl peptide receptor 2/ALX pathway affords protection against bacterial LPS-induced pathologic changes in the murine adrenal cortex.

    PubMed

    Buss, Nicholas A P S; Gavins, Felicity N E; Cover, Patricia O; Terron, Andrea; Buckingham, Julia C

    2015-07-01

    Hypothalamo-pituitary-adrenocortical dysfunction contributes to morbidity and mortality in a high proportion of patients with sepsis. Here, we provide new insights into the underlying adrenal pathology. Using a murine model of endotoxemia (LPS injection), we demonstrate that adrenal insufficiency is triggered early in the disease. LPS induced a local inflammatory response in the adrenal gland within 4 hours of administration, coupled with increased expression of mRNAs for annexin A1 (AnxA1) and the formyl peptide receptors [(Fprs) 1, 2, and 3], a loss of lipid droplets in cortical cells (index of availability of cholesterol, the substrate for steroidogenesis), and a failure to mount a steroidogenic response to ACTH. Deletion of AnxA1 or Fpr2/3 in mice prevented lipid droplet loss, but not leukocyte infiltration. LPS increased adrenal myeloid differentiation primary response gene 88 and TLR2 mRNA expression, but not lymphocyte antigen 96 or TLR4. By contrast, neutrophil depletion prevented leukocyte infiltration and increased AnxA1, Fpr1, and Fpr3 mRNAs but had no impact on lipid droplet loss. Our novel data demonstrate that AnxA1 and Fpr2 have a critical role in the manifestation of adrenal insufficiency in this model, through regulation of cholesterol ester storage, suggesting that pharmacologic interventions targeting the AnxA1/FPR/ALX pathway may provide a new approach for the maintenance of adrenal steroidogenesis in sepsis.-Buss, N. A. P. S., Gavins, F. N. E., Cover, P. O., Terron, A., Buckingham, J. C. Targeting the annexin 1-formyl peptide receptor 2/ALX pathway affords protection against bacterial LPS-induced pathologic changes in the murine adrenal cortex. PMID:25818588

  1. Hericium erinaceus suppresses LPS-induced pro-inflammation gene activation in RAW264.7 macrophages.

    PubMed

    Kim, Young-Ock; Lee, Sang-Won; Oh, Chung-Hun; Rhee, Yun-Hee

    2012-06-01

    The aim of this study was to investigate the anti-inflammatory properties of each fraction of Hericium erinaceus (HE). The ethanol extract from HE was partitioned with different solvents in the order of increasing polarity. The treatment with 10-100 ?g/mL of each fraction did not reduce RAW 264.7 cell viability except ethyl acetate fraction. Among the various extracts, the chloroform fraction showed the most potent activity against nitric oxide (NO), prostaglandin E(2) (PGE(2)) and reactive oxygen species (ROS). The western blotting and reverse transcriptase polymerase chain reaction (RT-PCR) analyses revealed that chloroform fraction from HE (CHE) significantly reduced the protein level of iNOS and cyclooxygenase-2 (COX-2) or mRNA levels of iNOS in lipopolysaccharide-induced macrophages. Furthermore, CHE inhibited the translocation of nuclear factor (NF)-?B p65 subunit, phsophorylation of I-?B, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK) in a dose-dependent manner. Furthermore, the activation of both activator protein-1 (AP-1) and NF ?B in the nucleus were abrogated by CHE with luciferase assay. In conclusion, these results indicate that CHE may provide an anti-inflammatory effect by attenuating the generation of excessive NO, PGE(2), and ROS and by suppressing the expression of pro-inflammatory genes through the inhibition of NF-?B and JNK activity. PMID:22126451

  2. CCL3/MIP-1 alpha is not involved in the LPS-induced fever and its pyrogenic activity depends on CRF.

    PubMed

    Soares, Denis Melo; Figueiredo, Maria José; Martins, Juliano Manvailer; Machado, Renes Resende; Kanashiro, Alexandre; Malvar, David do Carmo; Pessini, Andréa Carla; Roth, Joachim; Souza, Glória Emília Petto

    2009-05-01

    The fever induced by lipopolysaccharide (LPS) depends on both prostaglandin-dependent and -independent pathways. One of the prostaglandin-independent pathways is sequentially orchestrated by pre-formed pyrogenic factor derived from LPS-stimulated macrophages (PFPF), corticotrophin releasing factor (CRF), endothelin-1 (ET-1) and interleukin-1 (IL-1). As macrophage-inflammatory-protein (MIP)-1 alpha (synonym CCL3) also induces a prostaglandin independent fever, the aim of the present study was to investigate a possible participation of CCL3/MIP-1 alpha within the prostaglandin-independent pathway of LPS-induced fever which depends on PFPF, CRF and ET-1. Therefore, rats received intracerebroventricular (i.c.v.) pre-treatment with anti-CCL3 monoclonal antibody (1 and 5 ng) at 1 h and 15 min before injection of LPS (lipopolysaccharide from E. coli; 5, 50 or 100 microg kg(-1), i.v.) or CCL3/MIP-1 alpha (500 pg, i.c.v.). Both doses of anti-CCL3 did not change the basal temperature but abolished the fever induced by CCL3/MIP-1 alpha. When given at the higher dose, anti-CCL3 did not influence the fever induced by i.v. injection of different doses of LPS, or i.c.v. administration of PFPF (200 ng), CRF (3 microg) or ET-1 (1 pmol). Bosentan, a non-selective ET(A/B) receptors antagonist (10 microg kg(-1), i.v.), reduced the fever induced by LPS but not that induced by CCL3/MIP-1 alpha. In contrast, alpha-helical CRF(9-41) (a non-selective CRF R1/R2 receptor antagonist; 25 microg injected i.c.v.) reduced CCL3/MIP-1 alpha-induced fever. In conclusion, the present results indicate that: i) CCL3/MIP-1 alpha is not an endogenous mediator of LPS-induced fever; ii) it is even not involved in the prostaglandin-independent pathway of the LPS-fever cascade and iii) its pyrogenic activity depends on synthesis/release of CRF. PMID:19285486

  3. Modulating effects of prenatal stress on hyperthermia induced in adult rat offspring by restraint or LPS-induced stress

    Microsoft Academic Search

    Makoto Hashimoto; Tatsuo Watanabe; Takashi Fujioka; Nobusuke Tan; Hiroshi Yamashita; Shoji Nakamura

    2001-01-01

    The present study was carried out to investigate the effects of prenatal stress on stress-induced hyperthermia in adult rats. Prenatal stress was administered daily for 3 days (embryonic days 15–17) by restraining pregnant rats in a small cage either for 30 or 240 min. After birth, foster mothers raised the pups. Offspring were tested at 9–10-weeks-old. Changes in body temperature

  4. Lipopolysaccharide-induced microglial activation in culture: temporal profiles of morphological change and release of cytokines and nitric oxide

    Microsoft Academic Search

    Y. Nakamura; Q. S. Si; K. Kataoka

    1999-01-01

    Microglial activation has been considered as a result of neuronal damage, however, recently it becomes to recognize as a possible cause of the damage in various neurodegenerative diseases. To elucidate the mechanism of the microglial activation, we examined the time course of lipopolysaccharide (LPS)-induced change in morphology and the release of cytokines and nitric oxide (NO) in cultured microglia from

  5. The fatty acid amide hydrolase (FAAH) inhibitor PF-3845 acts in the nervous system to reverse LPS-induced tactile allodynia in mice

    PubMed Central

    Booker, Lamont; Kinsey, Steven G; Abdullah, Rehab A; Blankman, Jacqueline L; Long, Jonathan Z; Ezzili, Cyrine; Boger, Dale L; Cravatt, Benjamin F; Lichtman, Aron H

    2012-01-01

    BACKGROUND AND PURPOSE Inflammatory pain presents a problem of clinical relevance and often elicits allodynia, a condition in which non-noxious stimuli are perceived as painful. One potential target to treat inflammatory pain is the endogenous cannabinoid (endocannabinoid) system, which is comprised of CB1 and CB2 cannabinoid receptors and several endogenous ligands, including anandamide (AEA). Blockade of the catabolic enzyme fatty acid amide hydrolase (FAAH) elevates AEA levels and elicits antinociceptive effects, without the psychomimetic side effects associated with ?9-tetrahydrocannabinol (THC). EXPERIMENTAL APPROACH Allodynia was induced by intraplantar injection of LPS. Complementary genetic and pharmacological approaches were used to determine the strategy of blocking FAAH to reverse LPS-induced allodynia. Endocannabinoid levels were quantified using mass spectroscopy analyses. KEY RESULTS FAAH (?/?) mice or wild-type mice treated with FAAH inhibitors (URB597, OL-135 and PF-3845) displayed an anti-allodynic phenotype. Furthermore, i.p. PF-3845 increased AEA levels in the brain and spinal cord. Additionally, intraplantar PF-3845 produced a partial reduction in allodynia. However, the anti-allodynic phenotype was absent in mice expressing FAAH exclusively in the nervous system under a neural specific enolase promoter, implicating the involvement of neuronal fatty acid amides (FAAs). The anti-allodynic effects of FAAH-compromised mice required activation of both CB1 and CB2 receptors, but other potential targets of FAA substrates (i.e. µ-opioid, TRPV1 and PPAR? receptors) had no apparent role. CONCLUSIONS AND IMPLICATIONS AEA is the primary FAAH substrate reducing LPS-induced tactile allodynia. Blockade of neuronal FAAH reverses allodynia through the activation of both cannabinoid receptors and represents a promising target to treat inflammatory pain. LINKED ARTICLES This article is part of a themed section on Cannabinoids in Biology and Medicine. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.165.issue-8. To view Part I of Cannabinoids in Biology and Medicine visit http://dx.doi.org/10.1111/bph.2011.163.issue-7 PMID:21506952

  6. Lipopolysaccharide pretreatment inhibits LPS-induced human umbilical cord mesenchymal stem cell apoptosis via upregulating the expression of cellular FLICE-inhibitory protein.

    PubMed

    Hou, Yu Sen; Liu, Ling Ying; Chai, Jia Ke; Yu, Yong Hui; Duan, Hong Jie; Hu, Quan; Yin, Hui Nan; Wang, Yi He; Zhuang, Shu Bo; Fan, Jun; Chu, Wan Li; Ma, Li

    2015-08-01

    Mesenchymal stem cell (MSC)-based regenerative therapy is currently regarded as a novel approach with which to repair damaged tissues. However, the efficiency of MSC transplantation is limited due to the low survival rate of engrafted MSCs. Lipopolysaccharide (LPS) production is increased in numerous diseases and serves an essential function in the regulation of apoptosis in a variety of cell types. Previous studies have indicated that low?dose LPS pretreatment contributes to cytoprotection. In the current study, LPS was demonstrated to induce apoptosis in human umbilical cord mesenchymal stem cells (hUCMSCs) via the activation of caspase, in a dose?dependent manner. Low?dose LPS pretreatment may protect hUCMSCs against apoptosis induced by high?dose LPS, by upregulating the expression of cellular FADD?like IL?1??converting enzyme?inhibitory protein (c?FLIP). The results of the present study indicate that pretreatment with an appropriate concentration of LPS may alleviate high-dose LPS-induced apoptosis. PMID:25955291

  7. miR-15a/16 are upreuglated in the serum of neonatal sepsis patients and inhibit the LPS-induced inflammatory pathway

    PubMed Central

    Wang, Xiaoliang; Wang, Xiaoli; Liu, Xuelian; Wang, Xiaoli; Xu, Jiaju; Hou, Shanshan; Zhang, Xiaohui; Ding, Yanjie

    2015-01-01

    Infection in neonates, particular the neonatal sepsis continues to be a global problem with significant morbidity and mortality. The diagnosis of neonatal sepsis is complicated by nonspecific clinical symptomatology, a high-false negative rate, and a delay in obtaining blood culture results. MicroRNAs (miRNAs) have recently been used as finger prints for sepsis, and have been validated to be potential sepsis biomarker recently. In the present study, we investigated the level of several miRNAs, such as miR-15a, miR-16, miR-15b, and miR-223, which have been identified as a biomarker in adult sepsis, in neonatal sepsis patients, and then we analyzed the association of miR-15a/16 with the patient prognosis. Results demonstrated that the level of miR-15a/16 was up-regulated in neonatal sepsis patients than in normal neonatal subjects; however, no statistical difference was disclosed in the miR-15b and miR-223 level between two groups. And the ROC analysis indicated the miR-15a and miR-16 were potent fingerprints for diagnosing neonate sepsis. In order to explore the miR-15a/16 function on the lipopolysaccharide (LPS)-induced inflammatory pathway, the mice macrophage RAW264.7 cells were transiently transfected with miR-15a/16 mimics. And it was demonstrated that the miR-15a/16 transfection down-regulated the Toll-like receptor 4 (TLR4) and Interleukin-1 receptor-associated kinase 1 (IRAK-1) transcription level with a statistical difference in the LPS treated cells. And the suppression capability of miR-15a/16 on the expression of TLR-4 and IRAK-1 were evaluated by western blot. Thus, in present study, we identified miR-15a/16 as potential biomarker for the diagnosis and prognosis of neonatal sepsis, and the upregulated miR-15a/16 downregulated the LPS-induced inflammatory pathway.

  8. A heteroglycan from the cyanobacterium Nostoc commune modulates LPS-induced inflammatory cytokine secretion by THP-1 monocytes through phosphorylation of ERK1/2 and Akt.

    PubMed

    Olafsdottir, Astridur; Thorlacius, Gudny Ella; Omarsdottir, Sesselja; Olafsdottir, Elin Soffia; Vikingsson, Arnor; Freysdottir, Jona; Hardardottir, Ingibjorg

    2014-09-25

    Cyanobacteria (blue-green algae) have been consumed as food and used in folk medicine since ancient times to alleviate a variety of diseases. Cyanobacteria of the genus Nostoc have been shown to produce complex exopolysaccharides with antioxidant and antiviral activity. Furthermore, Nostoc sp. are common in cyanolichen symbiosis and lichen polysaccharides are known to have immunomodulating effects. Nc-5-s is a heteroglycan isolated from free-living colonies of Nostoc commune and its structure has been characterized in detail. The aim of this study was to determine the effects of Nc-5-s on the inflammatory response of lipopolysaccharide (LPS)-stimulated human THP-1 monocytes and how the effects are mediated. THP-1 monocytes primed with interferon-? and stimulated with LPS in the presence of Nc-5-s secreted less of the pro-inflammatory cytokine interleukin (IL)-6 and more of the anti-inflammatory cytokine IL-10 than THP-1 monocytes stimulated without Nc-5-s. In contrast, Nc-5-s increased LPS-induced secretion of the pro-inflammatory cytokines tumor necrosis factor (TNF)-? and IL-8. Nc-5-s decreased LPS-induced phosphorylation of the extracellular regulated kinase (ERK)1/2 and Akt kinase, but did not affect phosphorylation of the p38 kinase, activation of the nuclear factor kappa B pathway, nor DNA binding of c-fos. These results show that Nc-5-s has anti-inflammatory effects on IL-6 and IL-10 secretion by THP-1 monocytes, but its effects are pro-inflammatory when it comes to TNF-? and IL-8. Furthermore, they show that the effects of Nc-5-s may be mediated through the ERK1/2 pathway and/or the Akt/phosphoinositide 3-kinase pathway and their downstream effectors. The ability of Nc-5-s to decrease IL-6 secretion, increase IL-10 secretion and moderate ERK1/2 activation indicates a potential for its development as an anti-inflammatory agent. PMID:24877713

  9. Surfactant lipids regulate LPS-induced interleukin-8 production in A549 lung epithelial cells by inhibiting translocation of TLR4 into lipid raft domains

    PubMed Central

    Abate, Wondwossen; Alghaithy, Abdulaziz A.; Parton, Joan; Jones, Kenneth P.; Jackson, Simon K.

    2010-01-01

    In addition to providing mechanical stability, growing evidence suggests that surfactant lipid components can modulate inflammatory responses in the lung. However, little is known of the molecular mechanisms involved in the immunomodulatory action of surfactant lipids. This study investigates the effect of the lipid-rich surfactant preparations Survanta®, Curosurf®, and the major surfactant phospholipid dipalmitoylphosphatidylcholine (DPPC) on interleukin-8 (IL-8) gene and protein expression in human A549 lung epithelial cells using immunoassay and PCR techniques. To examine potential mechanisms of the surfactant lipid effects, Toll-like receptor 4 (TLR4) expression was analyzed by flow cytometry, and membrane lipid raft domains were separated by density gradient ultracentrifugation and analyzed by immunoblotting with anti-TLR4 antibody. The lipid-rich surfactant preparations Survanta®, Curosurf®, and DPPC, at physiological concentrations, significantly downregulated lipopolysaccharide (LPS)-induced IL-8 expression in A549 cells both at the mRNA and protein levels. The surfactant preparations did not affect the cell surface expression of TLR4 or the binding of LPS to the cells. However, LPS treatment induced translocation of TLR4 into membrane lipid raft microdomains, and this translocation was inhibited by incubation of the cells with the surfactant lipid. This study provides important mechanistic details of the immune-modulating action of pulmonary surfactant lipids. PMID:19648651

  10. Ginsenoside Rh2 Downregulates LPS-Induced NF- ? B Activation through Inhibition of TAK1 Phosphorylation in RAW 264.7 Murine Macrophage.

    PubMed

    Lian, Li-Hua; Jin, Quan; Song, Shun-Zong; Wu, Yan-Ling; Bai, Ting; Jiang, Shuang; Li, Qian; Yang, Ning; Nan, Ji-Xing

    2013-01-01

    The present study was carried out to evaluate the inhibitory effects of ginsenoside Rh2 on nuclear-factor- (NF-) ? B in lipopolysaccharide- (LPS-) activated RAW 264.7 murine macrophages. RAW 264.7 cells were pretreated with indicated concentrations of ginsenoside Rh2 for 1?h prior to the incubation of LPS (1? ? g/mL) for indicated time period. Ginsenoside Rh2 reduced CD14 and Toll-like receptor 4 (TLR4) expressions 24?h after LPS stimulation. Furthermore, ginsenoside Rh2 significantly inhibited TGF-beta-activated kinase 1 (TAK1) phosphorylation 30?min after LPS stimulation. Ginsenoside Rh2 was further shown to inhibit NF- ? B p65 translocation into the nucleus by suppressing I ? B- ? degradation. Also, LPS increased mRNA expression of TNF- ? and IL-1 ? time-dependently, while TQ reduced TNF- ? within 3?h and IL-1 ? within 1?h. And we firstly found that pretreatment of ginsenoside Rh2 successively inhibited hypoxia-inducible factor- (HIF-) 1 ? expression increased by LPS. In conclusion, ginsenoside Rh2 may inhibit LPS-induced NF- ? B activation and reduce HIF-1 ? accumulation, suggesting that ginsenoside Rh2 may be considered as a potential therapeutic candidate for chronic inflammatory diseases. PMID:23483870

  11. Anethole, a Medicinal Plant Compound, Decreases the Production of Pro-Inflammatory TNF-? and IL-1? in a Rat Model of LPS-Induced Periodontitis.

    PubMed

    Moradi, Janet; Abbasipour, Fatemeh; Zaringhalam, Jalal; Maleki, Bita; Ziaee, Narges; Khodadoustan, Amin; Janahmadi, Mahyar

    2014-01-01

    Periodontitis (PD) is known to be one of most prevalent worldwide chronic inflammatory diseases. There are several treatments including antibiotics for PD; however, since drug resistance is an increasing problem, new drugs particularly derived from plants with fewer side effects are required. The effects of trans-anethole on IL-1 ? and TNF-? level in a rat model of PD were investigated and compared to ketoprofen. Eschericia coli lipopolysaccharide (LPS, 30 µg) was injected bilaterally into the palatal gingiva (3 µL/site) between the upper first and second molars every two days for 10 days in anesthetized rats. Administration of either trans-anethole (10 or 50 mg/Kg, i.p.) or ketoprofen (10 mg/Kg, i.p.) was started 20 minute before LPS injection and continued for 10 days. Then, IL-1? and TNF-? levels were measured in blood samples by ELISA at day 0 (control) and at day 10. Anethole at both concentrations significantly suppressed IL-1? and TNF-? production when compared to LPS-treated rats. The suppressive effects of anethole on LPS-induced pro-inflammatory cytokines were almost similar as seen with ketoprofen. In conclusion, the present results suggest that anethole may have a potent inhibitory effect on PD through suppression of pro-inflammatory molecules; therefore it could be a novel therapeutic strategy for PD. PMID:25587321

  12. Anti-inflammatory effects of hydrophilic and lipophilic statins with hyaluronic acid against LPS-induced inflammation in porcine articular chondrocytes.

    PubMed

    Chang, Chih-Hung; Hsu, Yuan-Ming; Chen, Yu-Chun; Lin, Feng-Huei; Sadhasivam, Subramaniam; Loo, Siow-Tung; Savitha, Sivasubramanian

    2014-04-01

    The objective of the study is to understand the therapeutic effects of lipophilic (simvastatin) and hydrophilic statins (pravastatin) combined with/without hyaluronic acid for osteoarthritis by an in vitro LPS-induced inflammatory model of articular chondrocytes. HA in combination with different doses of simvastatin or pravastatin were used. Beside cytotoxicity, the influence of statins on NO production, pro-inflammatory cytokine, inflammatory mediators, and NF-?B p50 protein were analyzed. Finally, TUNEL assay was performed to detect DNA strand breakage. Two statins were less able to lower NF-?B activity when they were administrated along without HA. The gene expression demonstrates that simvastatin and pravastatin had the ability to decrease pro-inflammatory and inflammatory mediator levels. High dose simvastatin with or without HA down regulated inflammatory cytokines, but resulted in higher cytotoxicity. TUNEL assay confirms the regulatory effect of statins with or without HA over the apoptosis of chondrocytes, especially in hydrophilic statins. The significant down-regulation of inflammatory mediators suggests that intra-articular injection of HA in combination with statins might feasibly slow the progress of osteoarthritis. Administration of simvastatin or pravastatin with hyaluronic acid may produce beneficial effects for OA treatment, but with better results when hydrophilic statin was used. PMID:24302463

  13. LFP-20, a porcine lactoferrin peptide, ameliorates LPS-induced inflammation via the MyD88/NF-?B and MyD88/MAPK signaling pathways.

    PubMed

    Zong, Xin; Song, Deguang; Wang, Tenghao; Xia, Xi; Hu, Wangyang; Han, Feifei; Wang, Yizhen

    2015-10-01

    LFP-20 is one of the 20 amino acid anti-microbial peptides identified in the N terminus of porcine lactoferrin. Apart from its extensively studied direct anti-bacterial activity, its potential as an activator of immune-related cellular functions is unknown. Therefore, this study investigated its anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated pig alveolar macrophages in vitro and systemic inflammation in an in vivo mouse model. We found that the inhibitory effects of LFP-20 on production of pro-inflammatory cytokines were independent of its LPS-binding activity. However, they were associated with NF-?B and MAPK-dependent signaling. Furthermore, LFP-20 might directly influence MyD88 levels to block its interaction with NF-?B and MAPK-dependent signaling molecules that might alter LPS-mediated inflammatory responses in activated macrophages. Taken together, our data indicated that LFP-20 prevents the LPS-induced inflammatory response by inhibiting MyD88/NF-?B and MyD88/MAPK signaling pathways, and sheds light on the potential use of LFP-20 in the therapy of LPS-mediated sepsis. PMID:26003437

  14. Quantitative Proteomic Analysis of LPS-induced Differential Immune Response Associated with TLR4 Polymorphisms by Multiplex Amino Acid Coded Mass-tagging

    PubMed Central

    Gu, Sheng; Wang, Tianyi; Chen, Xian

    2013-01-01

    Polymorphisms at Toll-like receptor 4 (TLR4) gene have been found to be associated with immune disorders. A murine macrophage cell line GG2EE derived from C3H/HeJ mice with a polymorphism site at TLR4 is hyposensitive to lipopolysacchride (LPS). To study the molecular base of diverse TLR4-mediated immune responses, the proteomic changes in both TLR4-deficient and –wild-type cell lines in response to the same LPS challenge were quantitatively compared by using multiplex amino acid coded mass-tagging (AACT)/SILAC-assisted mass spectrometry (MS). This strategy allows encoding of two distinct cell populations with different stable isotope-tagged lysine residues as the ‘in-spectra’ quantitative markers. In MS analysis of tryptic peptides derived from the equally mixed three cell populations, the lysine-containing peptides originated from two LPS stimulated cell populations can be clearly distinguished by their different mass shifts from the un-stimulated and unlabeled counterpart. The LPS-induced differential protein expression in TLR4 –deficient and –wild-type proteomes were obtained by comparing the intensities of isotopically encoded peptides. Among the more than 900 proteins identified, 35 were found to be deregulated at different levels in these two cell lines stimulated by LPS. This multiplex mass-tagging methodology can be readily extended to other comparative proteomic quantitation of different cell populations. PMID:18654986

  15. Anethole, a Medicinal Plant Compound, Decreases the Production of Pro-Inflammatory TNF-? and IL-1? in a Rat Model of LPS-Induced Periodontitis

    PubMed Central

    Moradi, Janet; Abbasipour, Fatemeh; Zaringhalam, Jalal; Maleki, Bita; Ziaee, Narges; Khodadoustan, Amin; Janahmadi, Mahyar

    2014-01-01

    Periodontitis (PD) is known to be one of most prevalent worldwide chronic inflammatory diseases. There are several treatments including antibiotics for PD; however, since drug resistance is an increasing problem, new drugs particularly derived from plants with fewer side effects are required. The effects of trans-anethole on IL-1 ? and TNF-? level in a rat model of PD were investigated and compared to ketoprofen. Eschericia coli lipopolysaccharide (LPS, 30 µg) was injected bilaterally into the palatal gingiva (3 µL/site) between the upper first and second molars every two days for 10 days in anesthetized rats. Administration of either trans-anethole (10 or 50 mg/Kg, i.p.) or ketoprofen (10 mg/Kg, i.p.) was started 20 minute before LPS injection and continued for 10 days. Then, IL-1? and TNF-? levels were measured in blood samples by ELISA at day 0 (control) and at day 10. Anethole at both concentrations significantly suppressed IL-1? and TNF-? production when compared to LPS-treated rats. The suppressive effects of anethole on LPS-induced pro-inflammatory cytokines were almost similar as seen with ketoprofen. In conclusion, the present results suggest that anethole may have a potent inhibitory effect on PD through suppression of pro-inflammatory molecules; therefore it could be a novel therapeutic strategy for PD. PMID:25587321

  16. Flavonoid Fraction of Bergamot Juice Reduces LPS-Induced Inflammatory Response through SIRT1-Mediated NF-?B Inhibition in THP-1 Monocytes

    PubMed Central

    Risitano, Roberto; Currò, Monica; Cirmi, Santa; Ferlazzo, Nadia; Campiglia, Pietro; Caccamo, Daniela; Ientile, Riccardo; Navarra, Michele

    2014-01-01

    Plant polyphenols exert anti-inflammatory activity through both anti-oxidant effects and modulation of pivotal pro-inflammatory genes. Recently, Citrus bergamia has been studied as a natural source of bioactive molecules with antioxidant activity, but few studies have focused on molecular mechanisms underlying their potential beneficial effects. Several findings have suggested that polyphenols could influence cellular function by acting as activators of SIRT1, a nuclear histone deacetylase, involved in the inhibition of NF-?B signaling. On the basis of these observations we studied the anti-inflammatory effects produced by the flavonoid fraction of the bergamot juice (BJe) in a model of LPS-stimulated THP-1 cell line, focusing on SIRT1-mediated NF-?B inhibition. We demonstrated that BJe inhibited both gene expression and secretion of LPS-induced pro-inflammatory cytokines (IL-6, IL-1?, TNF-?) by a mechanism involving the inhibition of NF-?B activation. In addition, we showed that BJe treatment reversed the LPS-enhanced acetylation of p65 in THP-1 cells. Interestingly, increasing concentrations of Sirtinol were able to suppress the inhibitory effect of BJe via p65 acetylation, underscoring that NF-?B–mediated inflammatory cytokine production may be directly linked to SIRT1 activity. These results suggest that BJe may be useful for the development of alternative pharmacological strategies aimed at reducing the inflammatory process. PMID:25260046

  17. Chikusetsusaponin V inhibits inflammatory responses via NF-?B and MAPK signaling pathways in LPS-induced RAW 264.7 macrophages.

    PubMed

    Wang, Ting; Dai, Yanwen; Dun, Yaoyan; Zhang, Changcheng; Wan, Jingzhi; Deng, Lili; Zhou, Zhiyong; Liu, Chaoqi; Yuan, Ding

    2014-12-01

    Excessive activation of macrophages is implicated in various inflammation resulted injuries. Saponins from Panax japonicus (SPJ) have been shown to possess anti-inflammatory activities. However, whether Chikusetsusaponin V (CsV), the most abundant component of SPJ, can exert anti-inflammatory activities is unknown. The present study was aimed to investigate the anti-inflammatory effects of CsV in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells and the underlying mechanisms. Our data showed that CsV dose-dependently inhibited NO, iNOS, TNF-? and IL-1? expressions in LPS-stimulated RAW264.7 cells. Increased protein levels of nuclear NF-?B and elevated phosphorylation levels of ERK and JNK in LPS-stimulated RAW 264.7 cells were also found downregulated by CsV treatment. Furthermore, the increase of CD14 and TLR4 mRNA expression due to LPS stimulation were significantly reversed by CsV treatment. These results suggested that CsV attenuated LPS-induced inflammatory responses partly via TLR4/CD14-mediated NF-?B and MAPK pathways. PMID:25228203

  18. Molecular characterization and expression analysis of a putative LPS-induced TNF-alpha factor (LITAF) from pearl oyster Pinctada fucata.

    PubMed

    Zhang, Dianchang; Jiang, Jingjing; Jiang, Shigui; Ma, Jianjun; Su, Tianfeng; Qiu, Lihua; Zhu, Caiyan; Xu, Xinping

    2009-09-01

    The lipopolysaccharide-induced TNF-alpha factor (LITAF) is a novel transcription factor, which plays an important role in regulating the expression of TNF-alpha and various inflammatory cytokines in response to LPS stimulation and forms a dependent signaling pathway separated from NF-kappaB. Herein, we described the identification and characterization of pearl oyster Pinctada fucata LPS-induced TNF-alpha factor gene (designated as poLITAF). The poLITAF cDNA was 932 bp long and consisted of a 5'-untranslated region (UTR) of 45 bp, a 3'-UTR of 497 bp with two cytokine RNA instability motifs (ATTTA), and an open reading frame (ORF) of 390 bp encoding a polypeptide of 129 amino acids with an estimated molecular mass of 13.5 kDa and a theoretical isoelectric point of 8.36. A LITAF domain at C-terminal was identified in the poLITAF using SMART analysis, which contained two conserved CXXC motifs. Homology analysis of the deduced amino acid sequence of the poLITAF with other known LITAF sequences by MatGAT software revealed that the poLITAF shared 44.2-67.4% similarity and 35.4-50.0% identity to the other known LITAF sequences. The expression level of poLITAF mRNA was the highest in digestive gland and gill, moderate in adductor muscle, gonad, intestine and mantle, the lowest in haemocytes. The poLITAF mRNA expression was significantly up-regulated at 24 h in gill and at 12 h in digestive gland after LPS stimulation respectively. These results suggested that the poLITAF was a constitutive and inducible acute-phase protein that perhaps involved in the innate immune response of pearl oyster. PMID:19426809

  19. INVOLVEMENT OF TOLL-LIKE RECEPTOR 4 AND MAPK PATHWAYS IN LPS-INDUCED CD40 EXPRESSION IN MONOCYTIC CELLS

    EPA Science Inventory

    CD40 is a co-stimulatory surface molecule actively expressed on mature dendritic cells (DC). Recent studies suggest that endotoxin (LPS) inhalation induces DC maturation in the airways of healthy volunteers. To characterize the effect of LPS on CD40 expression and underlying mech...

  20. Mammalian target of rapamycin complex 2 (mTORC2) regulates LPS-induced expression of IL-12 and IL-23 in human dendritic cells.

    PubMed

    Wei, Wen-Chi; Liu, Chih-Pin; Yang, Wen-Chin; Shyur, Lie-Fen; Sheu, Jyh-Horng; Chen, Swey-Shen; Yang, Ning-Sun

    2015-06-01

    IL-12 p40, a common subunit for both IL-12 p70 and IL-23, plays a critical role in the development of Th1 and Th17 cells and autoimmune diseases. Regulation of IL-12 p40 expression is thus considered to be a strategy for developing therapies for Th1- and Th17-mediated autoimmune diseases. The mTOR protein is a subunit mTORC1 and mTORC2. Although mTORC1 has been shown to mediate IL-12 p40 expression in DCs and relevant signaling, the role of mTORC2 in IL-12 p40 expression remains largely unclear. In the present study, we demonstrate that blocking mTORC2 activity using the phytochemical cytopiloyne can specifically inhibit LPS-induced expression of IL-12 p70, IL-23, and IL-12 p40 in human DCs. This regulation by mTORC2 involving Akt activation and the persistent phase of NF-?B activation is further confirmed by siRNA knockdown of Rictor and Sin1 gene expression and the use of alternative inhibition approaches. In terms of IL-12 p40 expression, our findings reveal a new role for the mTORC2 pathway that is antagonistic to that of mTORC1. Our study provides new insight into mTOR regulation of IL-12 p40-mediated Th1 (IFN-?) and Th17 (IL-17) responses and suggests that the phytochemical cytopiloyne might have useful applications in therapies for Th1 and Th17 cell-mediated inflammatory diseases. PMID:25877925

  1. Toll-like Receptor 2 Is Required for LPS-induced Toll-like Receptor 4 Signaling and Inhibition of Ion Transport in Renal Thick Ascending Limb*

    PubMed Central

    Good, David W.; George, Thampi; Watts, Bruns A.

    2012-01-01

    Previously we demonstrated that basolateral LPS inhibits HCO3? absorption in the renal medullary thick ascending limb (MTAL) through TLR4-dependent ERK activation. Here we report that the response of the MTAL to basolateral LPS requires TLR2 in addition to TLR4. The basolateral addition of LPS (ultrapure Escherichia coli K12) decreased HCO3? absorption in isolated, perfused MTALs from wild-type mice but had no effect in MTALs from TLR2?/? mice. In contrast, inhibition of HCO3? absorption by lumen LPS was preserved in TLR2?/? MTALs, indicating that TLR2 is involved specifically in mediating the basolateral LPS response. LPS also did not increase ERK phosphorylation in MTALs from TLR2?/? mice. TLR2 deficiency had no effect on expression of TLR4, MD-2, or MyD88. However, LPS-induced recruitment of MyD88 to the basolateral membrane was impaired in TLR2?/? MTALs. Inhibition of HCO3? absorption by LPS did not require CD14. Co-immunoprecipitation studies demonstrated an association between TLR4 and TLR2. Inhibition of HCO3? absorption by TLR2-specific ligands was preserved in MTALs from TLR4?/? mice. These results indicate that the effect of basolateral LPS to inhibit HCO3? absorption in the MTAL through MyD88-dependent ERK activation depends on a novel interaction between TLR4 and TLR2. TLR2 plays a dual role in the induction of intracellular signals that impair MTAL function, both through cooperation with TLR4 to mediate ERK signaling by LPS and through a TLR4-independent signaling pathway activated by Gram-positive bacterial ligands. Regulation of TLR2 expression and its interaction with TLR4 may provide new mechanisms for controlling and therapeutic targeting of TLR4-mediated LPS responses. PMID:22523073

  2. 11?-HSD1 modulates LPS-induced innate immune responses in adipocytes by altering expression of PTEN.

    PubMed

    Lai, Wenfang; Tian, Xue; Xiang, Qing; Chu, Kedan; Wei, Yicong; Deng, Jingti; Zhang, Shaoping; Brown, John; Hong, Guizhu

    2015-04-01

    Inhibition of 11?-hydroxysteroid dehydrogenase type 1 (11?-HSD1) represents a therapeutic target for treating hyperglycemia in type 2 diabetes. Here, we investigate the effects of 11?-HSD1 on the innate immune response of adipocytes to produce proinflammatory cytokines. The 11?-HSD1 inhibitor emodin, or 11?-HSD1-targeted small interfering RNA, dose dependently suppressed IL-6, IL-1?, and TNF-? expression in lipopolysaccharide-treated 3T3-L1 adipocytes. Inhibiting 11?-HSD1 also reduced phosphatase and tensin homologue (PTEN) expression, a negative regulator of phosphatidylinositol 3-kinase effects, whereas 1pM cortisone or dexamethasone induced IL-6 and PTEN levels. PTEN-targeted small interfering RNA decreased IL-6, IL-1?, and TNF-? without affecting 11?-HSD1 levels. Correspondingly, emodin increased phosphorylated protein kinase B (p-PKB) (Ser473) to PKB ratio but not p-PKB (Thr308) to PKB ratio. Emodin did not increase the p-PKB (Ser473) to PKB ratio when the rapamycin-insensitive companion of mTOR was depleted, further supporting the involvement of mammalian target of rapamycin complex 2 in PKB phosphorylation. Moreover, emodin suppressed phosphorylated inhibitor of ?B ? (p-I?B?) to I?B? ratio and reduced nuclear factor ? B subunit p50 in the nuclear fraction. In contrast, 1pM cortisone or dexamethasone decreased p-PKB (Ser473) to PKB ratio, increased p-I?B? to I?B? ratio, and increased nuclear NF-?B subunit p50. Additionally, wortmannin had similar effects on IL-6, p-PKB (Ser473) to PKB ratio, and p-I?B? to I?B? ratio as 1pM cortisone or dexamethasone. Finally, emodin treatment of streptozotocin diabetic rats on a high-fat diet reduced levels of IL-6, PTEN, Cluster of Differentiation 68, and the ratio of p-I?B? to I?B? in visceral fat, indicating that our findings in vitro may also apply to visceral fat in vivo. Together, these results suggest that inhibiting 11?-HSD1 reduces lipopolysaccharide-induced proinflammatory innate immune responses in adipocytes by down-regulating PTEN expression, leading to activation of the PI3K/PKB pathway. PMID:25734515

  3. p120 Modulates LPS-Induced NF-?B Activation Partially through RhoA in Bronchial Epithelial Cells

    PubMed Central

    Qin, Shenghui; Zhang, Yanli; Liu, Liwei; Wu, Renliang

    2014-01-01

    p120-Catenin (p120) is an adherens junction protein recognized to regulate cell-cell adhesion. Emerging evidence indicates that p120 may also play an important role in inflammatory responses, and the regulatory mechanisms are still unknown. In the present study, we showed that p120 was associated with airway inflammation. p120 downregulation induced nuclear factor-?B (NF-?B) activation, accompanied with I?B? degradation, p65 nuclear translocation, and increased expression of interleukin-8 (IL-8) in lipopolysaccharide (LPS)- treated C57BL mice and human bronchial epithelial cells (BECs). Moreover, we first found that p120 directly coprecipitated with RhoA in BECs. After LPS stimulation, although total RhoA and p120-bound RhoA were unchanged, RhoA activity was increased. Y27632, a ROCK inhibitor, could partially inhibit nuclear translocation of p65. Overexpression of p120 inactivated RhoA and NF-?B in BECs, whereas p120 loss significantly increased RhoA activity, p65 nuclear translocation, and IL-8 expression. Taken together, our study supports the regulatory role of p120 in airway inflammation and reveals that p120 may modulate NF-?B signaling partially through RhoA. PMID:24995336

  4. Translation control of TAK1 mRNA by hnRNP K modulates LPS-induced macrophage activation

    PubMed Central

    Liepelt, Anke; Mossanen, Jana C.; Denecke, Bernd; Heymann, Felix; De Santis, Rebecca; Tacke, Frank; Marx, Gernot; Ostareck, Dirk H.; Ostareck-Lederer, Antje

    2014-01-01

    Macrophage activation by bacterial lipopolysaccharides (LPS) is induced through Toll-like receptor 4 (TLR4). The synthesis and activity of TLR4 downstream signaling molecules modulates the expression of pro- and anti-inflammatory cytokines. To address the impact of post-transcriptional regulation on that process, we performed RIP-Chip analysis. Differential association of mRNAs with heterogeneous nuclear ribonucleoprotein K (hnRNP K), an mRNA-specific translational regulator in differentiating hematopoietic cells, was studied in noninduced and LPS-activated macrophages. Analysis of interactions affected by LPS revealed several mRNAs encoding TLR4 downstream kinases and their modulators. We focused on transforming growth factor-?-activated kinase 1 (TAK1) a central player in TLR4 signaling. HnRNP K interacts specifically with a sequence in the TAK1 mRNA 3? UTR in vitro. Silencing of hnRNP K does not affect TAK1 mRNA synthesis or stability but enhances TAK1 mRNA translation, resulting in elevated TNF-?, IL-1?, and IL-10 mRNA expression. Our data suggest that the hnRNP K-3? UTR complex inhibits TAK1 mRNA translation in noninduced macrophages. LPS-dependent TLR4 activation abrogates translational repression and newly synthesized TAK1 boosts macrophage inflammatory response. PMID:24751651

  5. Dexamethasone attenuates LPS-induced changes in expression of urea transporter and aquaporin proteins, ameliorating brain endotoxemia in mice

    PubMed Central

    Du, Yanwei; Meng, Yan; Lv, Xuejiao; Guo, Lirong; Wang, Xiaoqin; Su, Zhenzhong; Li, Lu; Li, Na; Zhao, Shuhua; Zhao, Lijing; Zhao, Xuejian

    2014-01-01

    Aim: AQP4 in the brain is involved in the occurrence and development of a variety of encephalopathy. AQPs family changes in kidney were accompanied by altered UTs family. The aim of this study was to observe AQP4 and UT-A3 expression in CNS and to explore their role in the pathogenesis of endotoxemia encephalopathy following peripheral LPS injection in mice. Methods: Endotoxemia was induced in C57Bl/6 mice by intraperitoneal injection of LPS. The expression of UT-A3 and AQP4 in brain were detected by Western blot and immunohistochemistry, the level of cytokines were detected by ELISA, and the content of LDH, AST/ALT, BUN and CREA were detected by colorimetric method. Results: As compared with the control group, in model group, the brain weight/ body weight ratio increased by 13%. Meanwhile, a 2.5 fold increase in LDH and a 1.2 fold increase in AST/ALT were found in peripheral serum (P < 0.05), and also, BUN and CREA increased 2.5 fold (P < 0.01). In addition to severe CNS injury in response to lipopolysaccharide, the contents of cytokines and the expression of AQP4 protein in hippocampal is increased (P < 0.05), while the expression of UT-A3 protein in the hippocampus and cortical astrocytes decreased (P < 0.05). And, in part, Dexa pretreatment attenuated those effects. Conclusions: In endotoxemia encephalopathy, AQPs and UTs which regulate the functions of cell membrane are both altered. We suggested that the molecular mechanisms of regulation in endotoxemia may provide a new strategy for clinical treatment of the disease and drug binding sites. PMID:25674208

  6. LPS-induced NF-{kappa}B expression in THP-1Blue cells correlates with neopterin production and activity of indoleamine 2,3-dioxygenase

    SciTech Connect

    Schroecksnadel, Sebastian [Division of Biological Chemistry, Innsbruck Medical University, Innsbruck (Austria)] [Division of Biological Chemistry, Innsbruck Medical University, Innsbruck (Austria); Jenny, Marcel [Division of Biological Chemistry, Innsbruck Medical University, Innsbruck (Austria) [Division of Biological Chemistry, Innsbruck Medical University, Innsbruck (Austria); Division of Medical Biochemistry, Biocenter, Innsbruck Medical University, Innsbruck (Austria); Kurz, Katharina [Department of Internal Medicine, Innsbruck Medical University, Innsbruck (Austria)] [Department of Internal Medicine, Innsbruck Medical University, Innsbruck (Austria); Klein, Angela [Division of Medical Biochemistry, Biocenter, Innsbruck Medical University, Innsbruck (Austria)] [Division of Medical Biochemistry, Biocenter, Innsbruck Medical University, Innsbruck (Austria); Ledochowski, Maximilian [Department of Internal Medicine, Innsbruck Medical University, Innsbruck (Austria)] [Department of Internal Medicine, Innsbruck Medical University, Innsbruck (Austria); Uberall, Florian [Division of Medical Biochemistry, Biocenter, Innsbruck Medical University, Innsbruck (Austria)] [Division of Medical Biochemistry, Biocenter, Innsbruck Medical University, Innsbruck (Austria); Fuchs, Dietmar, E-mail: dietmar.fuchs@i-med.ac.at [Division of Biological Chemistry, Innsbruck Medical University, Innsbruck (Austria)] [Division of Biological Chemistry, Innsbruck Medical University, Innsbruck (Austria)

    2010-09-03

    Research highlights: {yields} LPS induces NF-{kappa}B, neopterin formation and tryptophan degradation in THP-1 cells. {yields} Close dose- and time-dependent correlations exist between these biochemical events. {yields} Data provides some evidence for a parallel induction of them upon TLR stimulation. {yields} Results can be of considerable relevance also in vivo. -- Abstract: Neopterin production is induced in human monocyte-derived macrophages and dendritic cells upon stimulation with Th1-type cytokine interferon-{gamma} (IFN-{gamma}). In parallel, IFN-{gamma} induces the tryptophan-(trp)-degrading enzyme indoleamine 2,3-dioxygenase (IDO) and triggers the formation of reactive oxygen species (ROS). Translocation of the signal transduction element nuclear factor-{kappa}B (NF-{kappa}B) is induced by ROS and accelerates the pro-inflammatory response by activation of other pro-inflammatory pathways. Therefore, a close relationship between NF-{kappa}B expression, the production of neopterin and the degradation of trp can be assumed, although this has not been demonstrated so far. In the present in vitro study we compared the influence of lipopolysaccharide (LPS) on NF-{kappa}B activation, neopterin formation and the degradation of trp in THP-1Blue cells, which represent the human myelomonocytic cell line THP-1 stably transfected with an NF-{kappa}B inducible reporter system. In cells stimulated with LPS, a significant induction of NF-{kappa}B was observed, and this was paralleled by an increase of kynureunine (kyn) and neopterin concentrations and a decline of trp. The increase of the kyn to trp quotient indicates accelerated IDO activity. Higher LPS concentrations and longer incubation of cells were associated with higher activities of all three biochemical pathways and significant correlations existed between NF-{kappa}B activation, neopterin release and trp degradation (all p < 0.001). We conclude that there is a parallel induction of NF-{kappa}B, neopterin formation and trp degradation in monocytic THP-1 cells, which is elicited by pro-inflammatory triggers like LPS during innate immune responses.

  7. Differential sensitivity to LPS-induced myocardial dysfunction in the isolated Brown Norway and Dahl S rat hearts: roles of mitochondrial function, NF?B activation and TNF-? production

    PubMed Central

    An, Jianzhong; Du, Jianhai; Wei, Na; Guan, Tongju; Camara, Amadou K.S.; Shi, Yang

    2011-01-01

    Recently we reported that BN rats were more resistant to lipopolysaccharide (LPS)-induced myocardial dysfunction than SS rats. This differential sensitivity was exemplified by reduced production of proinflammatory cytokines and diminished NF?B pathway activation. To further clarify the mechanisms of different susceptibility of these two strains to endotoxin, this study was designed to examine the alterations of cardiac and mitochondrial bioenergetics, proinflammatory cytokines, and signaling pathways after hearts were isolated and exposed to LPS ex vivo. Isolated BN and SS hearts were perfused with LPS (4 ?g/ml) for 30 min in the Langendorff preparation. LPS depressed cardiac function as evident by reduced left ventricular developed pressure as well as decreased peak rate of contraction and relaxation in SS hearts, but not in BN heart. These findings are consistent with our previous in vivo data. Under complex I substrates a higher O2 consumption and H2O2 production were observed in mitochondria from SS hearts than that from BN hearts. LPS significantly increased H2O2 levels in both SS and BN heart mitochondria; however the increase in O2 consumption and H2O2 production in BN heart mitochondria was much lower than that in SS heart mitochondria. Additionally LPS significantly decreased complex I activity in SS hearts but not in BN hearts. Furthermore, LPS induced higher levels of TNF-? and increased phosphorylation of I?B and p65 more in SS hearts than BN hearts. Our results clearly demonstrate that less mitochondrial dysfunction combined with a reduced production of TNF-? and diminished activation of NF?B are involved in the mechanisms by which isolated BN hearts were more resistant to LPS-induced myocardial dysfunction. PMID:22089203

  8. Lipid-soluble extracts from Salvia miltiorrhiza inhibit production of LPS-induced inflammatory mediators via NF-?B modulation in RAW 264.7 cells and perform antiinflammatory effects in vivo.

    PubMed

    Li, Meng; Zhang, Lei; Cai, Run-Lan; Gao, Yuan; Qi, Yun

    2012-08-01

    Salvia miltiorrhiza, a traditional Chinese herbal medicine, is used to treat various inflammatory diseases. In the present study, the antiinflammatory effects of S. miltiorrhiza lipid-soluble extracts (SMLE) were demonstrated in vitro and in vivo, along with its underlying mechanism of action. SMLE significantly inhibited the production of NO, TNF-?, IL-1? and IL-6 in lipopolysaccharides (LPS)-stimulated RAW 264.7 cells. SMLE also inhibited the LPS-induced degradation of I?B-? in the cytoplasm and the translocation of p65 to the nucleus in RAW 264.7 cells. In addition, SMLE inhibited the production of intracellular reactive oxygen species (ROS) and the surface expression of CD14 induced by LPS. In animal models, intraperitoneal administration of SMLE increased the survival rate of endotoxemia and sepsis in mice. The topical administration of SMLE significantly inhibited ear edema induced by PMA. It was found that SMLE inhibits the LPS-induced gene and protein expression of iNOS, TNF-?, IL-1? and IL-6 in macrophages by blocking NF-?B activation, and these effects are mediated, at least in part, through the inhibition of intracellular ROS generation and the surface expression of CD14. The results suggest a possible therapeutic application of SMLE in inflammatory diseases and provide scientific evidence in support of the traditional Chinese medical practice of treatment with S. miltiorrhiza. PMID:22228586

  9. Extracts of Actinidia arguta stems inhibited LPS-induced inflammatory responses through nuclear factor-?B pathway in Raw 264.7 cells.

    PubMed

    Kim, Hae-Young; Hwang, Kwang Woo; Park, So-Young

    2014-11-01

    The inflammatory response protects our body from bacteria and tumors, but chronic inflammation driven by the persistent activation of macrophages can lead to serious adverse effects including gastrointestinal problems, cardiac disorders, and a sore throat. Part of the ongoing research is focused on searching for antiinflammatory compounds from natural sources, so we investigated the effects of hardy kiwis (Actinidia arguta, Lauraceae) stems on inflammation induced by lipopolysaccharide (LPS) in Raw 264.7 cells to test the hypothesis that antiinflammatory effects of A. arguta stems were exerted through the inhibition of the nuclear factor (NF)-?B pathway. The methanol extract of A. arguta (20 ?g/mL) stems lowered nitric oxide production in LPS-stimulated Raw 264.7 cells by 40%. It was then partitioned with hexane, chloroform, ethyl acetate, butanol, and water based on the polarity of each compound. Among the 5 layers, the chloroform layer had the greatest inhibitory effect on LPS-stimulated nitric oxide production and inducible nitric oxide synthase mRNA expression in Raw 264.7 cells. However, the levels of prostaglandin E2 and cyclooxygease 2 were not altered. On the other hand, treatment of cells with the chloroform layer of A. arguta before LPS stimulation also reduced them RNA expression of proinflammatory cytokines including tumor necrosis factor ? and interleukin 1?. Nuclear translocation of NF-?B p50 and p65 subunits induced by LPS was also inhibited by treatment with the chloroform layer of A. arguta. This was accompanied with the reduced phosphorylation of mitogen-activated protein kinases including extracellular signal-regulated protein kinase 1/2, c-Jun N-terminal protein kinase, and p38. Taken together, these results suggest that chloroform layer of A. arguta exerted antiinflammatory effects by the inhibition of mitogen-activated protein kinase phosphorylation and nuclear translocation of NF-?B. PMID:25441150

  10. Pioglitazone inhibition of lipopolysaccharide-induced nitric oxide synthase is associated with altered activity of p38 MAP kinase and PI3K/Akt

    PubMed Central

    Xing, Bin; Xin, Tao; Hunter, Randy Lee; Bing, Guoying

    2008-01-01

    Background Previous studies have suggested that peroxisome proliferator activated receptor-gamma (PPAR-?)-mediated neuroprotection involves inhibition of microglial activation and decreased expression and activity of inducible nitric oxide synthase (iNOS); however, the underlying molecular mechanisms have not yet been well established. In the present study we explored: (1) the effect of the PPAR-? agonist pioglitazone on lipopolysaccharide (LPS)-induced iNOS activity and nitric oxide (NO) generation by microglia; (2) the differential role of p38 mitogen-activated protein kinase (p38 MAPK), c-Jun NH(2)-terminal kinase (JNK), and phosphoinositide 3-kinase (PI3K) on LPS-induced NO generation; and (3) the regulation of p38 MAPK, JNK, and PI3K by pioglitazone. Methods Mesencephalic neuron-microglia mixed cultures, and microglia-enriched cultures were treated with pioglitazone and/or LPS. The protein levels of iNOS, p38 MAPK, JNK, PPAR-?, PI3K, and protein kinase B (Akt) were measured by western blot. Different specific inhibitors of iNOS, p38MAPK, JNK, PI3K, and Akt were used in our experiment, and NO generation was measured using a nitrite oxide assay kit. Tyrosine hydroxylase (TH)-positive neurons were counted in mesencephalic neuron-microglia mixed cultures. Results Our results showed that pioglitazone inhibits LPS-induced iNOS expression and NO generation, and inhibition of iNOS is sufficient to protect dopaminergic neurons against LPS insult. In addition, inhibition of p38 MAPK, but not JNK, prevented LPS-induced NO generation. Further, and of interest, pioglitazone inhibited LPS-induced phosphorylation of p38 MAPK. Wortmannin, a specific PI3K inhibitor, enhanced p38 MAPK phosphorylation upon LPS stimulation of microglia. Elevations of phosphorylated PPAR-?, PI3K, and Akt levels were observed with pioglitazone treatment, and inhibition of PI3K activity enhanced LPS-induced NO production. Furthermore, wortmannin prevented the inhibitory effect of pioglitazone on the LPS-induced NO increase. Conclusion We demonstrate that pioglitazone protects dopaminergic neurons against LPS insult at least via inhibiting iNOS expression and NO generation, which is potentially mediated via inhibition of p38 MAPK activity. In addition, the PI3K pathway actively participates in the negative regulation of LPS-induced NO production. Our findings suggest that PPAR-? activation may involve differential regulation of p38 MAPK and of the PI3K/Akt pathway in the regulation of the inflammatory process. PMID:18205920

  11. The Protein Kinase PKR is Critical for LPS-induced iNOS Production, but Dispensable for Inflammasome Activation in Macrophages

    PubMed Central

    He, Yuan; Franchi, Luigi; Núñez, Gabriel

    2013-01-01

    The inflammasomes are multi-protein platforms that drive the activation of caspase-1 leading to the processing and secretion of biologically active IL-1? and IL-18. Different inflammasomes including NLRP3, NLRC4 and AIM2 are activated and assembled in response to distinct microbial or endogenous stimuli. However, the mechanisms by which upstream stimuli trigger inflammasome activation remain poorly understood. PKR, a protein kinase activated by viral infection, has been recently shown to be required for activation of the inflammasomes. Using macrophages from two different mouse strains deficient in PKR, we found that PKR is important for the induction of the inducible nitric oxide synthase (iNOS). However, PKR was dispensable for caspase-1 activation, processing of pro-IL-1?/IL-18 and secretion of IL-1? induced by stimuli that trigger the activation of NLRP3, NLRC4 and AIM2. These results indicate that PKR is not required for inflammasome activation in macrophages. PMID:23401008

  12. Ganoderma lucidum inhibits inducible nitric oxide synthase expression in macrophages.

    PubMed

    Woo, Connie W H; Man, Ricky Y K; Siow, Yaw L; Choy, Patrick C; Wan, Eric W Y; Lau, Chak S; O, Karmin

    2005-07-01

    Nitric oxide (NO) is a principal mediator in many physiological and pathological processes. Overproduction of NO via the inducible nitric oxide synthase (iNOS) has cytotoxic effect through the formation of peroxynitrite with superoxide anion. The iNOS is mainly expressed in macrophages and is able to produce large amount of NO. The expression of iNOS is mainly regulated at the transcriptional level. The iNOS-mediated NO production plays a role in the development of atherosclerosis. Ganoderma lucidum (G. lucidum, Linzhi or Reishi) is a traditional herbal medicine which is commonly used as health supplement. Several studies have demonstrated its effectiveness against cancer, immunological disorders and cardiovascular diseases. The objective of the present study was to investigate the effect of G. lucidum on iNOS-mediated NO production in macrophages. Human monocytic cell (THP-1) derived macrophages were incubated with lipopolysaccharide (LPS) for 24 h. Such treatment significantly stimulated NO production (253% versus the control). Such a stimulatory effect was resulted from increased iNOS mRNA expression (270% versus the control) and iNOS activity (169.5% versus the control) in macrophages. The superoxide anion level was also elevated (150% versus the control) in LPS-treated macrophages. Treatment of macrophages with G. lucidum extract (100 microg/ml) completely abolished LPS-induced iNOS mRNA expression and NO production. Such an inhibitory effect of G. lucidum was mediated via its antioxidant action against LPS-induced superoxide anion generation in macrophages. These results suggest that G. lucidum may exert a therapeutic effect against atherosclerosis via ameliorating iNOS-mediated NO overproduction in macrophages. PMID:16335796

  13. N-trans-feruloyltyramine inhibits LPS-induced NO and PGE2 production in RAW 264.7 macrophages: Involvement of AP-1 and MAP kinase signalling pathways.

    PubMed

    Jiang, Yunyao; Yu, Lingling; Wang, Myeong-Hyeon

    2015-06-25

    Mitogen-activated protein kinase (MAPK) signalling pathway can regulate inflammatory and immune responses. N-trans-feruloyltyramine (FLA) is an active phenylpropanoid compound. It possesses antioxidant, antimicrobial, anti-melanogenesis, and anticancer activities. However, the precise molecular mechanisms underlying FLA modulation of cytokine expression in LPS-stimulated RAW 264.7 macrophages have not been fully investigated. In this study, we examined the mechanisms underlying the immunomodulative effects of FLA isolated from Arcangelisia gusanlung. FLA strongly suppressed mRNA expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), but not tumor necrosis factor (TNF)-?, thereby inhibiting the production of nitric oxide (NO) and prostaglandin E2 (PGE2) in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Furthermore, FLA also inhibited nuclear translocation of activation protein (AP)-1, and simultaneously decreased the expression and phosphorylation of the c-Jun N-terminal kinase (JNK) protein. These results suggest that the anti-inflammatory effects of FLA might be attributed to downregulation of COX-2 and iNOS via suppression of AP-1 and the JNK signalling pathway in RAW 264.7 macrophages. PMID:25843058

  14. Secoiridoid glycosides from the root of Gentiana crassicaulis with inhibitory effects against LPS-induced NO and IL-6 production in RAW264 macrophages.

    PubMed

    He, Yu-Min; Zhu, Shu; Ge, Yue-Wei; Cai, Shao-Qing; Komatsu, Katsuko

    2015-07-01

    The root of Gentiana crassicaulis has been widely used for the treatment of rheumatism, arthralgia, apoplexy, jaundice and diabetes in traditional medicines, and contains secoiridoid glycosides as the main active ingredients. In the present study, five new secoiridoid glycosides, 6'-O-?-D-xylopyranosylgentiopicroside (1) and gentiananosides A-D (2-5), together with 11 known ones were isolated from the MeOH extract of dried roots of G. crassicaulis. Their structures were elucidated on the basis of extensive spectroscopic evidence. Of them, gentiananosides A (2) and B (3) were concluded to be novel secoiridoid glycosides with an ether linkage between C-2' of the sugar moiety and C-3 of the aglycone. Compounds 1, 4, 5, 7, 8, 12-14 exhibited moderate inhibitory effects against lipopolysaccharide-induced nitric oxide and interleukin-6 (IL-6) production in RAW264 cells, whereas 2 and 15 exhibited moderate inhibitory effects only against IL-6 production. PMID:25894073

  15. Punicalagin Induces Nrf2/HO-1 Expression via Upregulation of PI3K/AKT Pathway and Inhibits LPS-Induced Oxidative Stress in RAW264.7 Macrophages

    PubMed Central

    Xu, Xiaolong; Li, Hongquan; Hou, Xiaolin; Li, Deyin; He, Shasha; Wan, Changrong; Liu, Mingjiang; Liu, Fenghua

    2015-01-01

    Reactive oxygen species (ROS) and oxidative stress are thought to play a central role in potentiating macrophage activation, causing excessive inflammation, tissue damage, and sepsis. Recently, we have shown that punicalagin (PUN) exhibits anti-inflammatory activity in LPS-stimulated macrophages. However, the potential antioxidant effects of PUN in macrophages remain unclear. Revealing these effects will help understand the mechanism underlying its ability to inhibit excessive macrophage activation. Hemeoxygenase-1 (HO-1) exhibits antioxidant activity in macrophages. Therefore, we hypothesized that HO-1 is a potential target of PUN and tried to reveal its antioxidant mechanism. Here, PUN treatment increased HO-1 expression together with its upstream mediator nuclear factor-erythroid 2 p45-related factor 2 (Nrf2). However, specific inhibition of Nrf2 by brusatol (a specific Nrf2 inhibitor) dramatically blocked PUN-induced HO-1 expression. Previous research has demonstrated that the PI3K/Akt pathway plays a critical role in modulating Nrf2/HO-1 protein expression as an upstream signaling molecule. Here, LY294002, a specific PI3K/Akt inhibitor, suppressed PUN-induced HO-1 expression and led to ROS accumulation in macrophages. Furthermore, PUN inhibited LPS-induced oxidative stress in macrophages by reducing ROS and NO generation and increasing superoxide dismutase (SOD) 1 mRNA expression. These findings provide new perspectives for novel therapeutic approaches using antioxidant medicines and compounds against oxidative stress and excessive inflammatory diseases including tissue damage, sepsis, and endotoxemic shock. PMID:25969626

  16. Inhibition of inducible nitric oxide synthase and cyclooxygenase II by Platycodon grandiflorum saponins via suppression of nuclear factor-?B activation in RAW 264.7 cells

    Microsoft Academic Search

    Kwang Seok Ahn; Eun Jung Noh; Hai Lin Zhao; Sang Hoon Jung; Sam Sik Kang; Yeong Shik Kim

    2005-01-01

    Saponins are glycosidic compounds present in many edible and inedible plants. They exhibit potent biological activities in mammalian systems, including several beneficial effects such as anti-inflammation and immunomodulation. In this study, we investigated the effects of seven platycodin saponins on the activities of inducible nitric oxide synthase (iNOS) and cyclooxygenase II (COX-2) in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. We found

  17. Pulmonary Hypertension Triggered by Lipopolysaccharide in Ascites Susceptible and Resistant Broilers Is Not Amplified by Aminoguanidine, a Specific Inhibitor of Inducible Nitric Oxide Synthase

    Microsoft Academic Search

    O. T. Bowen; G. F. Erf; N. B. Anthony; R. F. Wideman

    Nitric oxide (NO) is a potent pulmonary vasodilator that modulates the pulmonary vasoconstric- tion and pulmonary hypertension (PH) triggered by bac- terial lipopolysaccharide (LPS) in broilers. The amplitude and duration of the LPS-induced PH are markedly en- hanced following pretreatment with N?-nitro-L-arginine methyl ester (L-NAME), which inhibits NO synthesis by both the constitutive (endothelial) and inducible (in- flammatory) forms of

  18. The Effect of PPE-Induced Emphysema and Chronic LPS-Induced Pulmonary Inflammation on Atherosclerosis Development in APOE*3-LEIDEN Mice

    PubMed Central

    Wagenaar, Gerry T. M.; Plomp, Jaap J.; van Eck, Miranda; Havekes, Louis M.; Rensen, Patrick C. N.; Hiemstra, Pieter S.; Berbée, Jimmy F. P.

    2013-01-01

    Background Chronic obstructive pulmonary disease (COPD) is characterized by pulmonary inflammation, airways obstruction and emphysema, and is a risk factor for cardiovascular disease (CVD). However, the contribution of these individual COPD components to this increased risk is unknown. Therefore, the aim of this study was to determine the contribution of emphysema in the presence or absence of pulmonary inflammation to the increased risk of CVD, using a mouse model for atherosclerosis. Because smoke is a known risk factor for both COPD and CVD, emphysema was induced by intratracheal instillation of porcine pancreatic elastase (PPE). Methods Hyperlipidemic APOE*3-Leiden mice were intratracheally instilled with vehicle, 15 or 30 µg PPE and after 4 weeks, mice received a Western-type diet (WTD). To study the effect of emphysema combined with pulmonary inflammation on atherosclerosis, mice received 30 µg PPE and during WTD feeding, mice were intranasally instilled with vehicle or low-dose lipopolysaccharide (LPS; 1 µg/mouse, twice weekly). After 20 weeks WTD, mice were sacrificed and emphysema, pulmonary inflammation and atherosclerosis were analysed. Results Intratracheal PPE administration resulted in a dose-dependent increase in emphysema, whereas atherosclerotic lesion area was not affected by PPE treatment. Additional low-dose intranasal LPS administration induced a low-grade systemic IL-6 response, as compared to vehicle. Combining intratracheal PPE with intranasal LPS instillation significantly increased the number of pulmonary macrophages and neutrophils. Plasma lipids during the study were not different. LPS instillation caused a limited, but significant increase in the atherosclerotic lesion area. This increase was not further enhanced by PPE. Conclusion This study shows for the first time that PPE-induced emphysema both in the presence and absence of pulmonary inflammation does not affect atherosclerotic lesion development. PMID:24303000

  19. DAP12 Stabilizes the C-terminal Fragment of the Triggering Receptor Expressed on Myeloid Cells-2 (TREM2) and Protects against LPS-induced Pro-inflammatory Response.

    PubMed

    Zhong, Li; Chen, Xiao-Fen; Zhang, Zhen-Lian; Wang, Zhe; Shi, Xin-Zhen; Xu, Kai; Zhang, Yun-Wu; Xu, Huaxi; Bu, Guojun

    2015-06-19

    Triggering receptor expressed on myeloid cells 2 (TREM2) is a DAP12-associated receptor expressed in microglia, macrophages, and other myeloid-derived cells. Previous studies have suggested that TREM2/DAP12 signaling pathway reduces inflammatory responses and promotes phagocytosis of apoptotic neurons. Recently, TREM2 has been identified as a risk gene for Alzheimer disease (AD). Here, we show that DAP12 stabilizes the C-terminal fragment of TREM2 (TREM2-CTF), a substrate for ?-secretase. Co-expression of DAP12 with TREM2 selectively increased the level of TREM2-CTF with little effects on that of full-length TREM2. The interaction between DAP12 and TREM2 is essential for TREM2-CTF stabilization as a mutant form of DAP12 with disrupted interaction with TREM2 failed to exhibit such an effect. Silencing of either Trem2 or Dap12 gene significantly exacerbated pro-inflammatory responses induced by lipopolysaccharides (LPS). Importantly, overexpression of either full-length TREM2 or TREM2-CTF reduced LPS-induced inflammatory responses. Taken together, our results support a role of DAP12 in stabilizing TREM2-CTF, thereby protecting against excessive pro-inflammatory responses. PMID:25957402

  20. SGLT-1-mediated glucose uptake protects intestinal epithelial cells against LPS-induced apoptosis and barrier defects: a novel cellular rescue mechanism?

    Microsoft Academic Search

    Linda C. H. Yu; Andrew N. Flynn; Jerrold R. Turner; Andre G. Buret

    2005-01-01

    Excessive apoptosis induced by enteric microbes leads to epithelial barrier defects. This mech- anism has been implicated in the pathogenesis of inflammatory bowel diseases (IBD) and bacterial enter- itis. The sodium-dependent glucose cotransporter (SGLT-1) is responsible for active glucose uptake in enterocytes. The aim was to investigate the effects of SGLT-1 glucose uptake on enterocyte apoptosis and barrier defects induced

  1. Absence of involvement of nitric oxide in LP-BM5-induced immunodeficiency syndrome.

    PubMed

    Akarid, K; Chenais, B; Chau, F; Sinet, M; Desforges, B; Gougerot-Pocidalo, M A

    1996-09-01

    To examine the role of nitric oxide (NO) in murine AIDS (MAIDS) pathogenesis, we determined NO production and inducible NOS (iNOS) mRNA expression in the macrophages of LP-BM5-infected mice, together with the in vivo effects of L-NAME, a competitive inhibitor of NO synthase. LP-BM5 infection induced neither spontaneous nitrite production nor iNOS mRNA expression. No differences in IFN gamma + LPS-induced nitrite production or iNOS mRNA expression were observed in macrophages, from non-infected or infected mice. Spleen weight, ecotropic MuLV replication, the blood lymphocyte phenotype and proliferative response of splenocytes were not modified by L-NAME. LP-BM5 infection did not increase macrophage NO production and NO production did not appear to protect against LP-BM5-induced immunodeficiency. PMID:8880143

  2. Astrocytic TLR4 expression and LPS-induced nuclear translocation of STAT3 in the sensory circumventricular organs of adult mouse brain.

    PubMed

    Nakano, Yousuke; Furube, Eriko; Morita, Shoko; Wanaka, Akio; Nakashima, Toshihiro; Miyata, Seiji

    2015-01-15

    The sensory circumventricular organs (CVOs) comprise the organum vasculosum of the lamina terminalis (OVLT), subfornical organ (SFO), and area postrema (AP) and lack the blood-brain barrier. The expression of Toll-like receptor 4 (TLR4) was seen at astrocytes throughout the sensory CVOs and at microglia in the AP and solitary nucleus around the central canal. The peripheral and central administration of lipopolysaccharide induced a similar pattern of nuclear translocation of STAT3. A microglia inhibitor minocycline largely suppressed lipopolysaccharide-induced astrocytic nuclear translocation of STAT3 in the OVLT and AP, but its effect was less in the SFO. PMID:25595264

  3. Redox-sensitive regulation of macrophage-inducible nitric oxide synthase expression in vitro does not correlate with the failure of apocynin to prevent lung inflammation induced by endotoxin.

    PubMed

    Via?ková, Daniela; Pekarová, Michaela; Crhák, Tomáš; Búcsaiová, Martina; Matiašovic, Ján; Lojek, Antonín; Kubala, Lukáš

    2011-04-01

    Reactive oxygen and nitrogen species are among the crucial mediators in the development of the pathological inflammatory process in the lungs and contribute to the damage of lung epithelium. The aim of the present study was to evaluate the potential of selected antioxidants or inhibitors of NADPH oxidase (glutathione, N-acetyl cysteine, trolox, apocynin, and diphenyleneiodonium chloride) to modulate nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) expression by mouse macrophages induced by lipopolysaccharide (LPS) in vitro and to evaluate the potential of apocynin to modulate the course of LPS-induced lung inflammation in vivo. All the tested drugs revealed inhibitory effects on LPS-induced NO production and iNOS expression in RAW 264.7 macrophages. Further, apocynin significantly inhibited activation of nuclear factor kappa B induced by LPS. Ex vivo, diphenyleneiodonium chloride and apocynin significantly reduced ROS production by inflammatory cells isolated from bronchoalveolar lavage fluid. In contrast, in vivo intranasal application of apocynin did not exert any significant effect on the course of lung inflammation in mice induced by LPS that was evaluated based on the accumulation of cells, interleukine-6, interleukine-12, RANTES, tumor necrosis factor-alpha, and protein concentration in bronchoalveolar lavage fluid and expression of iNOS in lung tissue. Only effected were the levels of nitrites 36 h after induction of lung inflammation that were reduced in the apocynin-treated group. In conclusion, our data suggest that the inhibitors of NADPH oxidase possess inhibitory potential against LPS-induced NO production by mouse macrophages; however, apocynin failed to reduce LPS-induced lung inflammation in mice. PMID:21093096

  4. 6-Hydroxydopamine and lipopolysaccharides induced DNA damage in astrocytes: involvement of nitric oxide and mitochondria.

    PubMed

    Gupta, Sonam; Goswami, Poonam; Biswas, Joyshree; Joshi, Neeraj; Sharma, Sharad; Nath, C; Singh, Sarika

    2015-01-15

    The present study was conducted to investigate the effect of the neurotoxins 6-hydroxydopamine and lipopolysaccharide on astrocytes. Rat astrocyte C6 cells were treated with different concentration of 6-hydroxydopamine (6-OHDA)/lipopolysaccharides (LPS) for 24 h. Both neurotoxins significantly decreased the viability of astrocytes, augmented the expression of inducible nitric oxide synthase (iNOS) and the astrocyte marker--glial fibrillar acidic protein. A significantly decreased mitochondrial dehydrogenase activity, mitochondrial membrane potential, augmented reactive oxygen species (ROS) level, caspase-3 mRNA level, chromatin condensation and DNA damage was observed in 6-OHDA/LPS treated astroglial cells. 6-OHDA/LPS treatment also caused the significantly increased expression of iNOS and nitrite level. Findings showed that 6-OHDA/LPS treatment caused mitochondrial dysfunction mediated death of astrocytes, which significantly involve the nitric oxide. Since we have observed significantly increased level of iNOS along with mitochondrial impairment and apoptotic cell death in astrocytes, therefore to validate the role of iNOS, the cells were co-treated with iNOS inhibitor aminoguanidine (AG, 100 ?M). Co-treatment of AG significantly attenuated the 6-OHDA/LPS induced cell death, mitochondrial activity, augmented ROS level, chromatin condensation and DNA damage. GFAP and caspase-3 expression were also inhibited with co-treatment of AG, although the extent of inhibition was different in both experimental sets. In conclusion, the findings showed that iNOS mediated increased level of nitric oxide acts as a key regulatory molecule in 6-OHDA/LPS induced mitochondrial dysfunction, DNA damage and apoptotic death of astrocytes. PMID:25726145

  5. Comparative analysis of the acute response of the trout, O. mykiss, head kidney to in vivo challenge with virulent and attenuated infectious hematopoietic necrosis virus and LPS-induced inflammation

    PubMed Central

    MacKenzie, Simon; Balasch, Joan C; Novoa, Beatriz; Ribas, Laia; Roher, Nerea; Krasnov, Aleksei; Figueras, Antonio

    2008-01-01

    Background The response of the trout, O. mykiss, head kidney to bacterial lipopolysaccharide (LPS) or active and attenuated infectious hematopoietic necrosis virus (IHNV and attINHV respectively) intraperitoneal challenge, 24 and 72 hours post-injection, was investigated using a salmonid-specific cDNA microarray. Results The head kidney response to i.p. LPS-induced inflammation in the first instance displays an initial stress reaction involving suppression of major cellular processes, including immune function, followed by a proliferative hematopoietic-type/biogenesis response 3 days after administration. The viral response at the early stage of infection highlights a suppression of hematopoietic and protein biosynthetic function and a stimulation of immune response. In fish infected with IHNV a loss of cellular function including signal transduction, cell cycle and transcriptional activity 72 hours after infection reflects the tissue-specific pathology of IHNV infection. attIHNV treatment on the other hand shows a similar pattern to native IHNV infection at 24 hours however at 72 hours a divergence from the viral response is seen and replace with a recovery response more similar to that observed for LPS is observed. Conclusion In conclusion we have been able to identify and characterise by transcriptomic analysis two different types of responses to two distinct immune agents, a virus, IHNV and a bacterial cell wall component, LPS and a 'mixed' response to an attenuated IHNV. This type of analysis will lead to a greater understanding of the physiological response and the development of effective immune responses in salmonid fish to different pathogenic and pro-inflammatory agents. PMID:18366750

  6. MR imaging and targeting of a specific alveolar macrophage subpopulation in LPS-induced COPD animal model using antibody-conjugated magnetic nanoparticles

    PubMed Central

    Al Faraj, Achraf; Shaik, Asma Sultana; Afzal, Sibtain; Al Sayed, Baraa; Halwani, Rabih

    2014-01-01

    Purpose Targeting and noninvasive imaging of a specific alveolar macrophage subpopulation in the lung has revealed the importance for early and better diagnosis and therapy of chronic obstructive pulmonary disease (COPD). In this study, the in vivo effect of pulmonary administration of iron oxide nanoparticles on the polarization profile of macrophages was assessed, and a noninvasive free-breathing magnetic resonance imaging (MRI) protocol coupled with the use of biocompatible antibody-conjugated superparamagnetic iron oxide (SPIO) nanoparticles was developed to enable specific targeting and imaging of a particular macrophage subpopulation in lipopolysaccharide-induced COPD mice model. Materials and methods Enzyme-linked immunosorbent assay, Real-time polymerase chain reaction, and flow cytometry analysis were performed to assess the biocompatibility of PEGylated dextran-coated SPIO nanoparticles. Specific biomarkers for M1 and M2 macrophages subsets were selected for conjugation with magnetic nanoparticles. MRI protocol using ultra-short echo time sequence was optimized to enable simultaneous detection of inflammation progress in the lung and detection of macrophages subsets. Flow cytometry and immunohistochemistry analysis were finally performed to confirm MRI readouts and to characterize the polarization profile of targeted macrophages. Results The tested SPIO nanoparticles, under the current experimental conditions, were found to be biocompatible for lung administration in preclinical settings. Cluster of differentiation (CD)86- and CD206-conjugated magnetic nanoparticles enabled successful noninvasive detection of M1 and M2 macrophage subpopulations, respectively, and were found to co-localize with inflammatory regions induced by lipopolysaccharide challenge. No variation in the polarization profile of targeted macrophages was observed, even though a continuum switch in their polarization might occur. However, further confirmatory studies are required to conclusively establish this observation. Conclusion Coupling of magnetic iron oxide nanoparticles with a specific antibody targeted to a particular macrophage subpopulation could offer a promising strategy for an early and better diagnosis of pulmonary inflammatory diseases using noninvasive MRI. PMID:24711699

  7. Microarray and Pathway Analysis Reveal Distinct Mechanisms Underlying Cannabinoid-Mediated Modulation of LPS-Induced Activation of BV-2 Microglial Cells

    PubMed Central

    Juknat, Ana; Kozela, Ewa; Rimmerman, Neta; Levy, Rivka; Gao, Fuying; Coppola, Giovanni; Geschwind, Daniel; Vogel, Zvi

    2013-01-01

    Cannabinoids are known to exert immunosuppressive activities. However, the mechanisms which contribute to these effects are unknown. Using lipopolysaccharide (LPS) to activate BV-2 microglial cells, we examined how ?9-tetrahydrocannabinol (THC), the major psychoactive component of marijuana, and cannabidiol (CBD) the non-psychoactive component, modulate the inflammatory response. Microarray analysis of genome-wide mRNA levels was performed using Illumina platform and the resulting expression patterns analyzed using the Ingenuity Pathway Analysis to identify functional subsets of genes, and the Ingenuity System Database to denote the gene networks regulated by CBD and THC. From the 5338 transcripts that were differentially expressed across treatments, 400 transcripts were found to be upregulated by LPS, 502 by CBD+LPS and 424 by THC+LPS, while 145 were downregulated by LPS, 297 by CBD+LPS and 149 by THC+LPS, by 2-fold or more (p?0.005). Results clearly link the effects of CBD and THC to inflammatory signaling pathways and identify new cannabinoid targets in the MAPK pathway (Dusp1, Dusp8, Dusp2), cell cycle related (Cdkn2b, Gadd45a) as well as JAK/STAT regulatory molecules (Socs3, Cish, Stat1). The impact of CBD on LPS-stimulated gene expression was greater than that of THC. We attribute this difference to the fact that CBD highly upregulated several genes encoding negative regulators of both NF?B and AP-1 transcriptional activities, such as Trib3 and Dusp1 known to be modulated through Nrf2 activation. The CBD-specific expression profile reflected changes associated with oxidative stress and glutathione depletion via Trib3 and expression of ATF4 target genes. Furthermore, the CBD affected genes were shown to be controlled by nuclear factors usually involved in regulation of stress response and inflammation, mainly via Nrf2/Hmox1 axis and the Nrf2/ATF4-Trib3 pathway. These observations indicate that CBD, and less so THC, induce a cellular stress response and that this response underlies their high immunosuppressant activities. PMID:23637839

  8. Rapamycin inhibits lipopolysaccharide induction of granulocyte-colony stimulating factor and inducible nitric oxide synthase expression in macrophages by reducing the levels of octamer-binding factor-2.

    PubMed

    Chou, Yuan-Yi; Gao, Jhen-I; Chang, Shwu-Fen; Chang, Po-Yuan; Lu, Shao-Chun

    2011-01-01

    This article reports an inhibitory effect of rapamycin on the lipopolysaccharide (LPS)-induced expression of both inducible nitric oxide synthase (iNOS) and granulocyte-colony stimulating factor (G-CSF) in macrophages and its underlying mechanism. The study arose from an observation that rapamycin inhibited the LPS-induced increase in octamer-binding factor-2 (Oct-2) protein levels through a mammalian target of rapamycin (mTOR)-dependent pathway in mouse RAW264.7 macrophages. As both iNOS and G-CSF are potential Oct-2 target genes, we tested the effect of rapamycin on their expression and found that it reduced the LPS-induced increase in iNOS and G-CSF mRNA levels and iNOS and G-CSF protein levels. Blocking of mTOR-signaling using a dominant-negative mTOR expression plasmid resulted in inhibition of the LPS-induced increase in iNOS and G-CSF protein levels, supporting the essential role of mTOR. Forced expression of Oct-2 using the pCG-Oct-2 plasmid overcame the inhibitory effect of rapamycin on the LPS-induced increase in iNOS and G-CSF mRNA levels. Chromatin immunoprecipitation assays showed that LPS enhanced the binding of Oct-2 to the iNOS and G-CSF promoters and that this effect was inhibited by pretreatment with rapamycin. Moreover, RNA interference knockdown of Oct-2 reduced iNOS and G-CSF expression in LPS-treated cells. The inhibitory effect of rapamycin on the LPS-induced increase in Oct-2 protein levels and on the iNOS and G-CSF mRNA levels was also detected in human THP-1 monocyte-derived macrophages. This study demonstrates that rapamycin reduces iNOS and G-CSF expression at the transcription level in LPS-treated macrophages by inhibiting Oct-2 expression. PMID:21114628

  9. Anti-inflammatory effect of alpha-linolenic acid and its mode of action through the inhibition of nitric oxide production and inducible nitric oxide synthase gene expression via NF-kappaB and mitogen-activated protein kinase pathways.

    PubMed

    Ren, Jie; Chung, Sung H

    2007-06-27

    Alpha-linolenic acid (ALA) isolated from Actinidia polygama fruits exhibits potent anti-inflammatory activity with an unknown mechanism. To elucidate the molecular mechanisms of ALA on pharmacological and biochemical actions in inflammation, we examined the effect of ALA on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in the murine macrophages cell line, RAW 264.7. We found that ALA has a strong inhibitory effect on the production of NO. ALA also inhibited inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and tumor necrosis factor-alpha (TNF-alpha) gene expressions induced by LPS. To explore the mechanisms associated with the inhibition of iNOS gene expression by ALA, we investigated its effect on LPS-induced nuclear factor-kappaB (NF-kappaB) activation. Treatment with ALA reduced a translocation of NF-kappaB subunit and NF-kappaB-dependent transcriptional activity. The activation of NF-kappaB was inhibited by prevention of the degradation of inhibitory factor-kappaBalpha. We also found that ALA inhibited LPS-induced phosphorylation of mitogen-activated protein kinases (MAPKs). In addition, the antinociceptive effect of ALA was also assessed by means of the acetic acid-induced abdominal constriction test and Randall-Selitto assay. ALA (5 and 10 mg/kg) showed the potent antinociceptive effects in these animal models. Taken together, these results suggest that ALA downregulates inflammatory iNOS, COX-2, and TNF-alpha gene expressions through the blocking of NF-kappaB and MAPKs activations in LPS-stimulated RAW 264.7 cells, which may be the mechanistic basis for the anti-inflammatory effect of ALA. PMID:17542608

  10. Down-regulatory effect of quercitrin gallate on nuclear factor-kappa B-dependent inducible nitric oxide synthase expression in lipopolysaccharide-stimulated macrophages RAW 264.7.

    PubMed

    Kim, Byung Hak; Cho, Sung Min; Reddy, Alavala Matta; Kim, Yeong Shik; Min, Kyung Rak; Kim, Youngsoo

    2005-06-01

    Quercetin 3-O-beta-(2''-galloyl)-rhamnopyranoside (QGR) is a naturally occurring quercitrin gallate, a polyphenolic compound isolated from Persicaria lapathifolia (Polygonaceae). In the present study, QGR compound was discovered to have inhibitory effect on nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated macrophages RAW 264.7. QGR compound attenuated LPS-induced synthesis of both mRNA and protein of inducible nitric oxide synthase (iNOS), in parallel, and inhibited LPS-induced luciferase expression as a reporter of iNOS promoter activity in the macrophages. As a mechanism of the anti-inflammatory action shown by QGR compound, suppression of nuclear factor (NF)-kappaB activation has been documented. QGR compound exhibited inhibitory effect on LPS-mediated NF-kappaB transcriptional activity in macrophages RAW 264.7. Furthermore, the compound inhibited LPS-mediated nuclear translocation of NF-kappaB p65 and DNA binding activity of NF-kappaB complex, in parallel, but did not influence LPS-mediated IkappaBalpha degradation. Taken together, QGR compound suppressed LPS-mediated NF-kappaB activation, specifically to nuclear localization step of NF-kappaB p65, which was attributable to its down-regulatory action on LPS-induced NO production and iNOS expression. PMID:15896337

  11. Alachlor and carbaryl suppress lipopolysaccharide-induced iNOS expression by differentially inhibiting NF-{kappa}B activation

    SciTech Connect

    Shimomura-Shimizu, Mifumi [Division of Microbiology, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501 (Japan); Sugiyama, Kei-ichi [Division of Microbiology, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501 (Japan); Muroi, Masashi [Division of Microbiology, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501 (Japan); Tanamoto, Ken-ichi [Division of Microbiology, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501 (Japan)]. E-mail: tanamoto@nihs.go.jp

    2005-07-08

    Nitric oxide (NO) produced by macrophages plays an important role in host defense and inflammation. We found that two agrochemicals, alachlor and carbaryl, inhibit lipopolysaccharide (LPS)-induced NO production by macrophages. In the present study, we investigated this inhibitory mechanism in RAW 264 cells. Both chemicals inhibited LPS-induced iNOS protein and mRNA expression as well as murine iNOS promoter activity. When treating these chemicals with reducing agents, the inhibition by carbaryl was reversed, but not the inhibition by alachlor. These chemicals also inhibited LPS-induced interferon-{beta} (IFN-{beta}) expression, an indispensable factor for LPS-induced iNOS expression. The inhibited iNOS expression, however, was not restored by exogenous IFN-{beta} supplementation. LPS-induced nuclear translocation of NF-{kappa}B, which is necessary for the expression of IFN-{beta} and iNOS, was inhibited by these chemicals: however, the LPS-induced degradation of I{kappa}B-{alpha} and I{kappa}B-{beta} was inhibited only by alachlor. These results indicate that alachlor and carbaryl differentially impair the LPS-induced NF-{kappa}B activation, leading to the inhibition of NO production.

  12. Vitamin D3 pretreatment alleviates renal oxidative stress in lipopolysaccharide-induced acute kidney injury.

    PubMed

    Xu, Shen; Chen, Yuan-Hua; Tan, Zhu-Xia; Xie, Dong-Dong; Zhang, Cheng; Xia, Mi-Zhen; Wang, Hua; Zhao, Hui; Xu, De-Xiang; Yu, De-Xin

    2015-08-01

    Increasing evidence demonstrates that reactive oxygen species plays important roles in sepsis-induced acute kidney injury. This study investigated the effects of VitD3 pretreatment on renal oxidative stress in sepsis-induced acute kidney injury. Mice were intraperitoneally injected with lipopolysaccharide (LPS, 2.0mg/kg) to establish an animal model of sepsis-induced acute kidney injury. In VitD3+LPS group, mice were orally pretreated with three doses of VitD3 (25?g/kg) at 1, 24 and 48h before LPS injection. As expected, oral pretreatment with three daily recommended doses of VitD3 markedly elevated serum 25(OH)D concentration and efficiently activated renal VDR signaling. Interestingly, LPS-induced renal GSH depletion and lipid peroxidation were markedly alleviated in VitD3-pretreated mice. LPS-induced serum and renal nitric oxide (NO) production was obviously suppressed by VitD3 pretreatment. In addition, LPS-induced renal protein nitration, as determined by 3-nitrotyrosine residue, was obviously attenuated by VitD3 pretreatment. Further analysis showed that LPS-induced up-regulation of renal inducible nitric oxide synthase (inos) was repressed in VitD3-pretreated mice. LPS-induced up-regulation of renal p47phox and gp91phox, two NADPH oxidase subunits, were normalized by VitD3 pretreatment. In addition, LPS-induced down-regulation of renal superoxide dismutase (sod) 1 and sod2, two antioxidant enzyme genes, was reversed in VitD3-pretreated mice. Finally, LPS-induced tubular epithelial cell apoptosis, as determined by TUNEL, was alleviated by VitD3 pretreatment. Taken together, these results suggest that VitD3 pretreatment alleviates LPS-induced renal oxidative stress through regulating oxidant and antioxidant enzyme genes. PMID:26013770

  13. Enhancement of lipopolysaccharide-induced nitric oxide and interleukin-6 production by PEGylated gold nanoparticles in RAW264.7 cells

    NASA Astrophysics Data System (ADS)

    Liu, Zhimin; Li, Wenqing; Wang, Feng; Sun, Chunyang; Wang, Lu; Wang, Jun; Sun, Fei

    2012-10-01

    While the immunogenicity and cytotoxicity of gold nanoparticles (AuNPs) are noted by many researchers, the mechanisms by which AuNPs exert these effects are poorly understood. In this study, we investigated the effects of polyethylene glycolylated AuNPs (PEG@AuNPs) on lipopolysaccharide (LPS)-induced nitric oxide (NO) and interleukin-6 (IL-6) production and the associated molecular mechanism in RAW264.7 cells. The results showed that PEG@AuNPs were internalized more quickly by LPS-activated RAW264.7 cells than unstimulated cells, and they reached saturation within 24 hours. PEG@AuNPs enhanced LPS-induced production of NO and IL-6 and inducible nitric oxide synthase (iNOS) expression in RAW264.7 cells, partially by activating p38 mitogen-activated protein kinases (p38 MAPK) and nuclear factor-kappaB pathways. In addition, the p38 MAPK inhibitor SB203580 attenuated PEG@AuNP-enhanced LPS-induced NO production and iNOS expression. Overproduction of NO and IL-6 is known to be closely correlated with the pathology of many diseases and inflammations. Thus, it is speculated that the highly biocompatible gold nanoparticles can induce immunotoxicity due to their potency to stimulate macrophages to release aberrant or excessive pro-inflammatory mediators.While the immunogenicity and cytotoxicity of gold nanoparticles (AuNPs) are noted by many researchers, the mechanisms by which AuNPs exert these effects are poorly understood. In this study, we investigated the effects of polyethylene glycolylated AuNPs (PEG@AuNPs) on lipopolysaccharide (LPS)-induced nitric oxide (NO) and interleukin-6 (IL-6) production and the associated molecular mechanism in RAW264.7 cells. The results showed that PEG@AuNPs were internalized more quickly by LPS-activated RAW264.7 cells than unstimulated cells, and they reached saturation within 24 hours. PEG@AuNPs enhanced LPS-induced production of NO and IL-6 and inducible nitric oxide synthase (iNOS) expression in RAW264.7 cells, partially by activating p38 mitogen-activated protein kinases (p38 MAPK) and nuclear factor-kappaB pathways. In addition, the p38 MAPK inhibitor SB203580 attenuated PEG@AuNP-enhanced LPS-induced NO production and iNOS expression. Overproduction of NO and IL-6 is known to be closely correlated with the pathology of many diseases and inflammations. Thus, it is speculated that the highly biocompatible gold nanoparticles can induce immunotoxicity due to their potency to stimulate macrophages to release aberrant or excessive pro-inflammatory mediators. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr31355c

  14. Ethyl acetate extract from Angelica Dahuricae Radix inhibits lipopolysaccharide-induced production of nitric oxide, prostaglandin E2 and tumor necrosis factor-alphavia mitogen-activated protein kinases and nuclear factor-kappaB in macrophages.

    PubMed

    Kang, Ok-Hwa; Lee, Go-Hoon; Choi, Hyuk Joon; Park, Pil Sang; Chae, Hee-Sung; Jeong, Seung-Il; Kim, Youn-Chul; Sohn, Dong Hwan; Park, Hyun; Lee, John Hwa; Kwon, Dong-Yeul

    2007-04-01

    Angelica dahurica (Umbelliferae) has been used to treat headache of common cold, supraorbital neuralgia, painful swelling on the body, nasal stuffiness, leukorrhea and arthralgia due to wind-dampness in Korean traditional medicine. It is also claimed to be effective in the treatment of acne, erythema, headache, toothache, sinusitis, colds and flu. The present study focused whether the ethyl acetate extract from Angelica Dahuricae Radix (EAAD) inhibits production of nitric oxide (NO), prostaglandin E(2) (PGE(2)) and tumor necrosis factor (TNF)-alpha, as well as expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nuclear factor-kappaB (NF-kappaB) and mitogen-activated protein kinases (MAPKs) in lipopolysaccharide (LPS)-stimulated macrophages. EAAD inhibited LPS-induced NO, PGE(2) and TNF-alpha production as well as expression of iNOS and COX-2 in RAW 264.7 cells. EAAD inhibited LPS-induced TNF-alpha production in THP-1 cells. Furthermore, EAAD suppressed LPS-induced phosphorylation of p38 MAPK and extracellular-signal regulated kinases 1/2 (ERK1/2), I-kappaBalpha degradation, and NF-kappaB activation in RAW 264.7 cells. These results suggest that EAAD has the inhibitory effects on LPS-induced TNF-alpha, NO and PGE(2) production, and expression of iNOS and COX-2 in macrophage through blockade in the phosphorylation of MAPKs, following I-kappaBalpha degradation and NF-kappaB activation. PMID:17229575

  15. Nitric oxide in neuroimmune feedback signaling

    Microsoft Academic Search

    Teresa L. Krukoff; Wendy W. Yang

    2001-01-01

    The gaseous neurotransmitter, nitric oxide (NO), has been implicated in regulation of the hypothalamo-pituitary-adrenal (HPA) axis. NO donors attenuate lipopolysaccharide (LPS)-induced release of corticotropin releasing factor (CRF) in vitro and NO synthase (NOS) inhibitors potentiate and prolong activation of the HPA axis by LPS in vivo. Changes in activities of the NO synthase isoforms, neuronal NOS (nNOS), endothelial NOS (eNOS),

  16. Central but not systemic inhibition of inducible nitric oxide synthase modulates oxytocin release during endotoxemic shock.

    PubMed

    Stabile, Angelita Maria; Moreto, Viviana; Antunes-Rodrigues, José; Carnio, Evelin Capellari

    2010-04-01

    Previous studies have shown that immunological challenges as lipopolysaccharide (LPS) administration increases plasma oxytocin (OT) concentration. Nitric oxide (NO), a free radical gas directly related to the immune system has been implicated in the central modulation of neuroendocrine adaptive responses to immunological stress. This study aimed to test the hypothesis that the NO pathway participates in the control of OT release induced by LPS injection. For this purpose, adult male Wistar rats received bolus intravenous (i.v.) injection of LPS, preceded or not by i.v. or intracerebroventricular (i.c.v.) injections of aminoguanidine (AG), a selective inducible nitric oxide synthase (iNOS) inhibitor. Rats were decapitated after 2, 4 and 6h of treatment, for measurement of OT by radioimmunoassay. In a separate set of experiments, mean arterial pressure (MAP) and heart rate (HR) were measured every 15 min over 6h, using a polygraph. These studies revealed that LPS reduced MAP and increased HR at 4 and 6h post-injection. LPS significantly increased plasma OT concentration at 2 and 4h post-injection. Pre-treatment with i.c.v. AG further increased plasma OT concentration and attenuated the LPS-induced decrease in MAP, however, i.v. AG failed to show similar effects. Thus, iNOS pathway may activate a central inhibitory control mechanism that attenuates OT secretion during endotoxemic shock. PMID:19932725

  17. 6-(Methylsulfinyl)hexyl isothiocyanate suppresses inducible nitric oxide synthase expression through the inhibition of Janus kinase 2-mediated JNK pathway in lipopolysaccharide-activated murine macrophages.

    PubMed

    Uto, Takuhiro; Fujii, Makoto; Hou, De-Xing

    2005-10-15

    6-(Methylsulfinyl)hexyl isothiocyanate (6-MITC) is an active ingredient of Wasabi (Wasabia japonica (Miq.) Matsumura), which is a very popular pungent spice in Japan. To clarify the cellular signaling mechanism underlying the anti-inflammatory action of 6-MITC, we investigated the effects of 6-MITC on the expression of inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-activated murine macrophage RAW264 cells. 6-MITC showed a dose-dependent inhibition of LPS-induced nitric oxide (NO), iNOS mRNA and protein. LPS caused the c-Jun phosphorylation (a major component of AP-1) and IkappaB-alpha degradation. 6-MITC suppressed LPS-induced c-Jun phosphorylation, but did not inhibit IkappaB-alpha degradation. Cellular signaling analysis using MAPK-(U0126 for MEK1/2, SB203580 for p38 kinase and SP600125 for JNK) and Jak2-specific (AG490) inhibitors demonstrated that LPS stimulated iNOS expression via activating Jak2-mediated JNK, but not ERK and p38, pathway. 6-MITC suppressed iNOS expression through the inhibition of Jak2-mediated JNK signaling cascade with the attendant to AP-1 activation. In addition, the structure-activity study revealed that the inhibitory potency of methylsulfinyl isothiocyanates (MITCs) depended on the methyl chain length. These findings provide the molecular basis for the first time that 6-MITC is an effective agent to attenuate iNOS production. PMID:16139249

  18. Absence of the cell cycle inhibitor p21Cip1 reduces LPS-induced NO release and activation of the transcription factor NF-kappaB in mixed glial cultures.

    PubMed

    Tusell, Josep Maria; Saura, Josep; Serratosa, Joan

    2005-01-01

    We have studied possible differences in glial activation between cells from wild-type and p21Cip1-/- mice. We compared the effect of serum mitogenic stimulation on proliferation rate and on the total number of glial cells after 7 days of culture. No differences between wild-type and p21Cip1-/- glial cells were observed. We also compared the effect of lipopolysaccharide (LPS) from Escherichia coli, an agent widely used to induce glial activation. Nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha) release, and nuclear factor kappa-B (NF-kappaB) activation were evaluated as indicators of glial activation. We observed an attenuation of NO release and NF-kappaB activation in p21Cip1-/- glial cells when compared with glial cells from wild-type mice. In contrast, TNF-alpha release was enhanced in p21Cip1-/- glia. These results suggest that the cell cycle inhibitor p21Cip1 plays a role in the inflammatory response induced by LPS. PMID:15390102

  19. Altered Regulation of Renal Nitric Oxide and Atrial Natriuretic Peptide Systems in Lipopolysaccharide-induced Kidney Injury.

    PubMed

    Bae, Eun Hui; Kim, In Jin; Ma, Seong Kwon; Lee, Jong Un; Kim, Soo Wan

    2011-10-01

    Nitric oxide (NO) and atrial natriuretic peptide (ANP) may induce vascular relaxation by increasing the production of cyclic guanosine monophosphate (cGMP), an important mediator of vascular tone during sepsis. This study aimed to determine whether regulation of NO and the ANP system is altered in lipopolysaccharide (LPS)-induced kidney injury. LPS (10 mg.kg(-1)) was injected in the tail veins of male Sprague-Dawley rats; 12 hours later, the kidneys were removed. Protein expression of NO synthase (NOS) and neutral endopeptidase (NEP) was determined by semiquantitative immunoblotting. As an index of synthesis of NO, its stable metabolites (nitrite/nitrate, NOx) were measured using colorimetric assays. mRNA expression of the ANP system was determined by real-time polymerase chain reaction. To determine the activity of guanylyl cyclase (GC), the amount of cGMP generated in response to sodium nitroprusside (SNP) and ANP was calculated. Creatinine clearance decreased and fractional excretion of sodium increased in LPS-treated rats compared with the controls. Inducible NOS protein expression increased in LPS-treated rats, while that of endothelial NOS, neuronal NOS, and NEP remained unchanged. Additionally, urinary and plasma NOx levels increased in LPS-treated rats. SNP-stimulated GC activity remained unchanged in the glomerulus and papilla in the LPS-treated rats. mRNA expression of natriuretic peptide receptor (NPR)-C decreased in LPS-treated rats, while that of ANP and NPR-A did not change. ANP-stimulated GC activity reduced in the glomerulus and papilla. In conclusion, enhancement of the NO/cGMP pathway and decrease in ANP clearance were found play a role in the pathogenesis of LPS-induced kidney injury. PMID:22128259

  20. Ulinastatin suppresses lipopolysaccharide-induced prostaglandin E2 synthesis and nitric oxide production through the downregulation of nuclear factor??B in BV2 mouse microglial cells.

    PubMed

    Sung, Yun-Hee; Shin, Mal-Soon; Ko, Il-Gyu; Kim, Sung-Eun; Kim, Chang-Ju; Ahn, Hyun-Jong; Yoon, Hye-Sun; Lee, Bong-Jae

    2013-05-01

    Ulinastatin is an intrinsic serine-protease urinary trypsin inhibitor that can be extracted and purified from human urine. Urinary trypsin inhibitors are widely used to treat patients with acute inflammatory disorders, such as shock and pancreatitis. However, although the anti-inflammatory activities of urinary trypsin inhibitors have been investigated, the mechanisms underlying their actions are not yet fully understood. In the present study, we evaluated the effect of ulinastatin on lipopolysaccharide (LPS)-induced inflammation in relation with nuclear factor-?B (NF-?B) activation using BV2 mouse microglial cells. To accomplish this, we performed a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, reverse transcription-polymerase chain reaction (RT-PCR), western blot analysis, electrophoretic mobility gel shift assay (EMSA), prostaglandin E(2) (PGE(2)) immunoassay and nitric oxide (NO) detection. The results demonstrated that ulinastatin suppressed PGE2 synthesis and NO production by inhibiting the LPS-induced mRNA and protein expression of cyclooxygenase-2 (COX-2) and inducible NO synthase (iNOS) in BV2 mouse microglial cells. Ulinastatin suppressed the activation of NF-?B in the nucleus. These findings demonstrate that ulinastatin exerts analgesic and anti-inflammatory effects that possibly occur via the suppression of COX-2 and iNOS expression through the downregulation of NF-?B activity. PMID:23546639

  1. The NADPH oxidase inhibitor apocynin induces nitric oxide synthesis via oxidative stress

    SciTech Connect

    Riganti, Chiara [Dipartimento di Genetica, Biologia e Biochimica, Universita di Torino, Via Santena 5/bis, 10126 Torino (Italy)], E-mail: chiara.riganti@unito.it; Costamagna, Costanzo; Doublier, Sophie; Miraglia, Erica; Polimeni, Manuela; Bosia, Amalia; Ghigo, Dario [Dipartimento di Genetica, Biologia e Biochimica, Universita di Torino, Via Santena 5/bis, 10126 Torino (Italy)

    2008-05-01

    We have recently shown that apocynin elicits an oxidative stress in N11 mouse glial cells and other cell types. Here we report that apocynin increased the accumulation of nitrite, the stable derivative of nitric oxide (NO), in the extracellular medium of N11 cell cultures, and the NO synthase (NOS) activity in cell lysates. The increased synthesis of NO was associated with increased expression of inducible NOS (iNOS) mRNA, increased nuclear translocation of the redox-sensitive transcription factor NF-{kappa}B and decreased intracellular level of its inhibitor IkB{alpha}. These effects, accompanied by increased production of H{sub 2}O{sub 2}, were very similar to those observed after incubation with bacterial lipopolysaccharide (LPS) and were inhibited by catalase. These results suggest that apocynin, similarly to LPS, induces increased NO synthesis by eliciting a generation of reactive oxygen species (ROS), which in turn causes NF-{kappa}B activation and increased expression of iNOS. Therefore, the increased bioavailability of NO reported in the literature after in vivo or in vitro treatments with apocynin might depend, at least partly, on the drug-elicited induction of iNOS, and not only on the inhibition of NADPH oxidase and the subsequent decreased scavenging of NO by oxidase-derived ROS, as it is often supposed.

  2. Original article Regulation of inducible nitric oxide synthase

    E-print Network

    Paris-Sud XI, Université de

    Original article Regulation of inducible nitric oxide synthase by dietary phytoestrogen in MCF-7 showed that at a concentration of 40 µg.mL­1, biochanin A decreased the levels of inducible nitric oxide synthase, thus inhibiting the production of nitric oxide, a known second mes- senger and inducer

  3. Bauer ketones 23 and 24 from Echinacea paradoxa var. paradoxa inhibit lipopolysaccharide-induced nitric oxide, prostaglandin E2 and cytokines in RAW264.7 mouse macrophages.

    PubMed

    Zhang, Xiaozhu; Rizshsky, Ludmila; Hauck, Catherine; Qu, Luping; Widrlechner, Mark P; Nikolau, Basil J; Murphy, Patricia A; Birt, Diane F

    2012-02-01

    Among the nine Echinacea species, E. purpurea, E. angustifolia and E. pallida, have been widely used to treat the common cold, flu and other infections. In this study, ethanol extracts of these three Echinacea species and E. paradoxa, including its typical variety, E. paradoxa var. paradoxa, were screened in lipopolysaccharide (LPS)-stimulated macrophage cells to assess potential anti-inflammatory activity. E. paradoxa var. paradoxa, rich in polyenes/polyacetylenes, was an especially efficient inhibitor of LPS-induced production of nitric oxide (NO), prostaglandin E2 (PGE2), interleukin-1 beta (IL-1?) and interleukin-6 (IL-6) by 46%, 32%, 53% and 26%, respectively, when tested at 20 ?g/ml in comparison to DMSO control. By bioactivity-guided fractionation, pentadeca-8Z-ene-11, 13-diyn-2-one (Bauer ketone 23) and pentadeca-8Z, 13Z-dien-11-yn-2-one (Bauer ketone 24) from E. paradoxa var. paradoxa were found primarily responsible for inhibitory effects on NO and PGE2 production. Moreover, Bauer ketone 24 was the major contributor to inhibition of inflammatory cytokine production in LPS-induced mouse macrophage cells. These results provide a rationale for exploring the medicinal effects of the Bauer ketone-rich taxon, E. paradoxa var. paradoxa, and confirm the anti-inflammatory properties of Bauer ketones 23 and 24. PMID:22133644

  4. Bauer Ketones 23 and 24 from Echinacea paradoxa var. paradoxa Inhibit Lipopolysaccharide-induced Nitric Oxide, Prostaglandin E2 and Cytokines in RAW 264.7 Mouse Macrophages

    PubMed Central

    Zhang, Xiaozhu; Rizshsky, Ludmila; Hauck, Catherine; Qu, Luping; Widrlechner, Mark P.; Nikolau, Basil J.; Murphy, Patricia A.; Birt, Diane F.

    2011-01-01

    Among the nine Echinacea species, E. purpurea, E. angustifolia and E. pallida, have been widely used to treat the common cold, flu and other infections. In our study, ethanol extracts of these three Echinacea species and E. paradoxa, including its typical variety, E. paradoxa var. paradoxa, were screened in lipopolysaccharide (LPS)-stimulated macrophage cells to assess potential anti-inflammatory activity. Echinacea paradoxa var. paradoxa, rich in polyenes/polyacetylenes, was an especially efficient inhibitor of LPS-induced production of nitric oxide (NO), prostaglandin E2 (PGE2), interleukin-1 beta (IL-1?) and interleukin-6 (IL-6) by 46%, 32%, 53% and 26%, respectively, when tested at 20 ?g/ml in comparison to DMSO control. By bioactivity-guided fractionation, pentadeca-8Z-ene-11, 13-diyn-2-one (Bauer ketones 23, compound 1) and pentadeca-8Z, 13Z-dien-11-yn-2-one (Bauer ketone 24, compound 2) from E. paradoxa var. paradoxa were found primarily responsible for inhibitory effects on NO and PGE2 production. Moreover, Bauer ketone 24 (compound 2) was the major contributor to inhibition of inflammatory cytokine production in LPS-induced mouse macrophage cells. These results provide a rationale for exploring the medicinal effects of the Bauer ketone-rich taxon, E. paradoxa var. paradoxa, and confirm the anti-inflammatory properties of Bauer ketones 23 and 24. PMID:22133644

  5. Microtubule Reconfiguration during Axonal Retraction Induced by Nitric Oxide

    E-print Network

    Baas, Peter W.

    Microtubule Reconfiguration during Axonal Retraction Induced by Nitric Oxide Yan He, Wenqian Yu study, we sought to test this hypothesis with regard to microtubules. When a donor of nitric oxide that actually caused microtubule levels to increase. The retractions induced by nitric oxide were remarkably

  6. Inhibitory effect of 6-hydroxy-7-methoxychroman-2-carboxylic acid phenylamide on nitric oxide and interleukin-6 production in macrophages

    Microsoft Academic Search

    Kyung Rak Min; Heesoon Lee; Byung Hak Kim; EunYong Chung; Sung Min Cho; Youngsoo Kim

    2005-01-01

    6-Hydroxy-7-methoxychroman-2-carboxylic acid phenylamide (CP compound) is a novel chemically synthetic compound with vitamin E-like chemical structure. In the present study, the CP compound was discovered to inhibit nitric oxide (NO) and interleukin (IL)-6 productions in lipopolysaccharide (LPS)-stimulated macrophages. Further, CP compound attenuated LPS-induced synthesis of mRNA and protein levels of inducible NO synthase (iNOS), in parallel, and inhibited iNOS promoter

  7. Synthesis of novel derivatives of esculentoside A and its aglycone phytolaccagenin, and evaluation of their haemolytic activity and inhibition of lipopolysaccharide-induced nitric oxide production.

    PubMed

    Gong, Wei; Jiang, Zhihui; Sun, Peng; Li, Ling; Jin, Yongsheng; Shao, Lucheng; Zhang, Wen; Liu, Baoshu; Zhang, Hongwei; Tang, Hua; Chen, Yufeng; Yi, Yanghua; Zhang, Dazhi

    2011-10-01

    A series of 46 compounds derived from esculentoside A and its aglycone were synthesized and characterized. The effect of these compounds on lipopolysaccharide (LPS)-induced NO production, haemolytic activity, and cell viability was evaluated. Structure-activity relationship was established by comparing the derivatives of esculentoside A with its aglycone derivatives. Both the aglycone and its derivatives showed higher inhibitory effects on LPS-induced NO production, and lower haemolytic activities than esculentoside A and its derivatives. PMID:22006712

  8. A combined extract of Cinnamomi Ramulus, Anemarrhenae Rhizoma and Alpiniae Officinari Rhizoma suppresses production of nitric oxide by inhibiting NF-kappaB activation in RAW 264.7 cells.

    PubMed

    Jeong, Mi-Young; Lee, Ji-Suk; Lee, Jae-Dong; Kim, Nam-Jae; Kim, Jin-Woo; Lim, Sabina

    2008-06-01

    An herbal mixture prepared with Cinnamomi Ramulus, Anemarrhenae Rhizoma and Alpiniae Officinari Rhizoma (CAA) is used in oriental medicine for treating several ailments. The purpose of this study was to determine the mechanisms by which CAA elicits an antiinflammatory effect on nitric oxide (NO) production in the mouse macrophage cell line RAW 264.7 cells. The results indicated that lipopolysaccharide (LPS)-induced NO production was inhibited by CAA in a dose-dependent manner. Western blotting and RT-PCR analysis demonstrated that CAA decreased LPS-induced inducible nitric oxide synthase (iNOS) protein and gene expression in RAW 264.7 cells. Furthermore, CAA inhibited the LPS-induced DNA binding activity of nuclear factor-kappa B (NF-kappaB) and this effect was mediated through inhibiting the degradation of inhibitory factor-kappaBalpha (IkappaBalpha). Therefore, the results demonstrate that CAA inhibits LPS-induced production of NO and expression of iNOS by blocking NF-kappaB activation. CAA might be a potential therapeutic candidate for treating inflammatory diseases such as arthritis. PMID:18446841

  9. Expression of Inducible Nitric Oxide Synthase in Experimental Viral Myocarditis

    Microsoft Academic Search

    Brigitte Glück; Ingrid Merkle; Gesche Dornberger; Axel Stelzner

    2000-01-01

    Nitric oxide (NO) is an important bioactive molecule with regulatory, cytotoxic or cytoprotective properties. In virus-induced myocarditis, NO mediates host defense mechanisms against the infection or causes cardiac dysfunctions. NO is synthesized from L-arginine by the enzyme nitric oxide synthase (NOS). The expression of the inducible form of the nitric oxide synthase (iNOS) is regulated by cytokines, involved in the

  10. Atypical “seizure-like” activity in cortical reverberating networks in vitro can be caused by LPS-induced inflammation: a multi-electrode array study from a hundred neurons

    PubMed Central

    Gullo, Francesca; Amadeo, Alida; Donvito, Giulia; Lecchi, Marzia; Costa, Barbara; Constanti, Andrew; Wanke, Enzo

    2014-01-01

    We show here that a mild sterile inflammation induced by the endotoxin lipopolysaccharide (LPS), in a neuron/astrocyte/microglial cortical network, modulates neuronal excitability and can initiate long-duration burst events resembling epileptiform seizures, a recognized feature of various central nervous neurodegenerative, neurological and acute systemic diseases associated with neuroinflammation. To study this action, we simultaneously analyzed the reverberating bursting activity of a hundred neurons by using in vitro multi-electrode array methods. ?5 h after LPS application, we observed a net increase in the average number of spikes elicited in engaged cells and within each burst, but no changes neither in spike waveforms nor in burst rate. This effect was characterized by a slow, twofold exponential increase of the burst duration and the appearance of rarely occurring long burst events that were never seen during control recordings. These changes and the time-course of microglia-released proinflammatory cytokine, tumor necrosis factor-alpha (TNF-?), were blocked by pre-treatment with 50 nM minocycline, an established anti-inflammatory agent which was inactive when applied alone. Assay experiments also revealed that application of 60 pM exogenous TNF-? after 12–15 h, produced non-washable changes of neuronal excitability, completely different from those induced by LPS, suggesting that TNF-? release alone was not responsible for our observed findings. Our results indicate that the link between neuroinflammation and hyperexcitability can be unveiled by studying the long-term activity of in vitro neuronal/astrocyte/microglial networks. PMID:25404893

  11. Sulfated derivative of 20(S)-ginsenoside Rh2 inhibits inflammatory cytokines through MAPKs and NF-kappa B pathways in LPS-induced RAW264.7 macrophages.

    PubMed

    Bi, Wen-Yan; Fu, Ben-Dong; Shen, Hai-Qing; Wei, Qian; Zhang, Cui; Song, Zhou; Qin, Qian-Qian; Li, Hui-Ping; Lv, Shuang; Wu, Shuai-Cheng; Yi, Peng-Fei; Wei, Xu-Bin

    2012-10-01

    In the previous study, we found that sulfated derivative B2 of ginsenoside Rh2 (Rh2-B2) has greater anti-inflammatory effects than 20(S)-ginsenoside Rh2. However, the anti-inflammatory mechanism of Rh2-B2 remains unclear. We therefore assessed the effects of Rh2-B2 on inflammatory cytokines in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. We found that Rh2-B2 (1-5 mg/L) significantly inhibited tumor necrosis factor alpha, interleukin (IL)-6, IL-1?, and increased IL-10 production from protein and mRNA levels. Furthermore, Rh2-B2 significantly inhibited the phosphorylation of p38 and c-Jun N-terminal kinase as well as decreased p65 nuclear factor kappa-light-chain-enhancer of activated B cells (NF-?B) translocation into the nucleus by nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha degradation. The present results indicate that Rh2-B2 inhibits the production of inflammatory cytokines induced by LPS through blocking mitogen-activated protein kinases and NF-?B signaling pathways. PMID:22614119

  12. Asymmetric dimethylarginine regulates the lipopolysaccharide-induced nitric oxide production in macrophages by suppressing the activation of NF-kappaB and iNOS expression.

    PubMed

    Pekarova, Michaela; Kubala, Lukas; Martiskova, Hana; Bino, Lucia; Twarogova, Michaela; Klinke, Anna; Rudolph, Tanja K; Kuchtova, Zdenka; Kolarova, Hana; Ambrozova, Gabriela; Kuchta, Radek; Kadlec, Jaroslav; Lojek, Antonin

    2013-08-01

    Two major effector systems are frequently implicated in the immune and endothelial cell alternations associated with inflammation. They include the enhanced production of reactive oxygen species and diminished bioavailability of nitric oxide (NO). Importantly, these processes can be regulated by endogenously produced methylarginines, inhibitors for NO derived from macrophages and endothelial cells. Therefore, the aim of this study was to show the potential pharmacological intervention of methylarginines (N(G)-methyl-L-arginine, L-NMMA; N(G), N(G)'-dimethyl-L-arginine-symmetric dimethylarginine, SDMA; and N(G), N(G)-dimethyl-L-arginine-asymmetric dimethylarginine, ADMA) in activation of murine peritoneal (RAW 264.7) and alveolar (MHS) macrophages with lipopolysaccharide from Gram-negative bacteria (LPS). The data presented in this study clearly declare that L-NMMA (1-50?M) and ADMA (10-50 ?M) significantly inhibited the LPS-induced NO production from macrophages in a concentration-dependent manner. It was demonstrated, for the first time, that the ADMA- and L-NMMA-induced down regulation of NO production was accompanied by reduced expression of mRNA and protein for inducible NO synthase as well as decreased activation of nuclear factor-?B. Importantly, we found a negative correlation between the ADMA-dependent reduction of NO production and ADMA-increased superoxide formation, which indicates that ADMA can negatively affect the balance in LPS-induced macrophage-derived production of reactive mediators. The only effect of SDMA was observed for LPS-triggered superoxide production, which was significantly decreased in its highest concentration (50 ?M). In summary, L-NMMA and ADMA can mediate their effects on macrophage activation via regulation of intracellular signaling pathways, which can affect critical functions in activated macrophages. PMID:23665490

  13. Recognition of Betaine as an Inhibitor of Lipopolysaccharide-Induced Nitric Oxide Production in Activated Microglial Cells

    PubMed Central

    Amiraslani, Banafsheh; Sabouni, Farzaneh; Abbasi, Shahsanam; Nazem, Habiballah; Sabet, Mohammadsadegh

    2012-01-01

    Background: Neuroinflammation, as a major outcome of microglia activation, is an important factor for progression of neurodegenerative disorders including Alzheimer's disease and Parkinson's disease. Microglial cells, as the first-line defense in the central nervous system, act as a source of neurotoxic factors such as nitric oxide (NO), a free radical which is involved in neuronal cell death. The aim of this study was to inhibit production of NO in activated microglial cells in order to decrease neurological damages that threat the central nervous system. Methods: An in vitro model of a newborn rat brain cell culture was used to examine the effect of betaine on the release of NO induced by lipopolysaccharide (LPS). Briefly, primary microglial cells were stimulated by LPS and after 2 minutes, they were treated by different concentrations of betaine. The production of NO was assessed by the Griess assay while cell viability was determined by the MTT assay. Results: Our investigations indicated that LPS-induced NO release was attenuated by betaine, suggesting that this compound might inhibit NO release. The effects of betaine on NO production in activated microglial cells after 24 h were "dose-dependent". It means that microglial cells which were treated with higher concentrations of betaine, released lower amounts of NO. Also our observations showed that betaine compound has no toxic effect on microglial cells. Conclusion: Betaine has an inhibitory effect on NO release in activated microglial cells and may be an effective therapeutic component to control neurological disorders. PMID:22801281

  14. Screening of Indonesian medicinal plants for inhibitor activity on nitric oxide production of RAW264.7 cells and antioxidant activity

    Microsoft Academic Search

    Eun-Mi Choi; Jae-Kwan Hwang

    2005-01-01

    Traditional Indonesian medicinal plants were screened for their inhibitory effects on the nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages and for the antioxidant activity through the evaluation of free radical scavenging effect and reducing power. The results of screening indicated that 50 methanolic extracts inhibited (>50%) lipopolysaccharides (LPS)-induced NO release from RAW264.7 cells at 50 ?g\\/ml, with 18

  15. Ginger extract inhibits LPS induced macrophage activation and function

    Microsoft Academic Search

    Sudipta Tripathi; David Bruch; Dilip S Kittur

    2008-01-01

    BACKGROUND: Macrophages play a dual role in host defence. They act as the first line of defence by mounting an inflammatory response to antigen exposure and also act as antigen presenting cells and initiate the adaptive immune response. They are also the primary infiltrating cells at the site of inflammation. Inhibition of macrophage activation is one of the possible approaches

  16. New role for L-arginine in regulation of inducible nitric-oxide-synthase-derived superoxide anion production in raw 264.7 macrophages.

    PubMed

    Pekarova, Michaela; Lojek, Antonin; Martiskova, Hana; Vasicek, Ondrej; Bino, Lucia; Klinke, A; Lau, D; Kuchta, Radek; Kadlec, Jaroslav; Vrba, Radimir; Kubala, Lukas

    2011-01-01

    Dietary supplementation with L-arginine was shown to improve immune responses in various inflammatory models. However, the molecular mechanisms underlying L-arginine effects on immune cells remain unrecognized. Herein, we tested the hypothesis that a limitation of L-arginine could lead to the uncoupled state of murine macrophage inducible nitric oxide synthase and, therefore, increase inducible nitric-oxide-synthase-derived superoxide anion formation. Importantly, we demonstrated that L-arginine dose- and time dependently potentiated superoxide anion production in bacterial endotoxin-stimulated macrophages, although it did not influence NADPH oxidase expression and activity. Detailed analysis of macrophage activation showed the time dependence between LPS-induced iNOS expression and increased O(2)(?-) formation. Moreover, downregulation of macrophage iNOS expression, as well as the inhibition of iNOS activity by NOS inhibitors, unveiled an important role of this enzyme in controlling O(2)(?-) and peroxynitrite formation during macrophage stimulation. In conclusion, our data demonstrated that simultaneous induction of NADPH oxidase, together with the iNOS enzyme, can result in the uncoupled state of iNOS resulting in the production of functionally important levels of O(2)(?-) soon after macrophage activation with LPS. Moreover, we demonstrated, for the first time that increased concentrations of L-arginine further potentiate iNOS-dependent O(2) (?-) formation in inflammatory macrophages. PMID:22219714

  17. New Role for L-Arginine in Regulation of Inducible Nitric-Oxide-Synthase-Derived Superoxide Anion Production in Raw 264.7 Macrophages

    PubMed Central

    Pekarova, Michaela; Lojek, Antonin; Martiskova, Hana; Vasicek, Ondrej; Bino, Lucia; Klinke, A.; Lau, D.; Kuchta, Radek; Kadlec, Jaroslav; Vrba, Radimir; Kubala, Lukas

    2011-01-01

    Dietary supplementation with L-arginine was shown to improve immune responses in various inflammatory models. However, the molecular mechanisms underlying L-arginine effects on immune cells remain unrecognized. Herein, we tested the hypothesis that a limitation of L-arginine could lead to the uncoupled state of murine macrophage inducible nitric oxide synthase and, therefore, increase inducible nitric-oxide-synthase-derived superoxide anion formation. Importantly, we demonstrated that L-arginine dose- and time dependently potentiated superoxide anion production in bacterial endotoxin-stimulated macrophages, although it did not influence NADPH oxidase expression and activity. Detailed analysis of macrophage activation showed the time dependence between LPS-induced iNOS expression and increased O2?? formation. Moreover, downregulation of macrophage iNOS expression, as well as the inhibition of iNOS activity by NOS inhibitors, unveiled an important role of this enzyme in controlling O2?? and peroxynitrite formation during macrophage stimulation. In conclusion, our data demonstrated that simultaneous induction of NADPH oxidase, together with the iNOS enzyme, can result in the uncoupled state of iNOS resulting in the production of functionally important levels of O2?? soon after macrophage activation with LPS. Moreover, we demonstrated, for the first time that increased concentrations of L-arginine further potentiate iNOS-dependent O2?? formation in inflammatory macrophages. PMID:22219714

  18. Zinc protoporphyrin inhibition of lipopolysaccharide-, lipoteichoic acid-, and peptidoglycan-induced nitric oxide production through stimulating iNOS protein ubiquitination

    SciTech Connect

    Chow, J.-M. [Section of Hematology-Oncology, Department of Internal Medicine, Taipei Municipal Wan Fang Hospital, Taipei Medical University, Taipei 110, Taiwan (China); Lin, H.-Y.; Shen, S.-C. [Graduate Institute of Medical Sciences, Taipei Medical University, Taipei 110, Taiwan (China); Wu, M.-S. [Department of Gastroenterology, Taipei Medical University Wan Fang Hospital, Taiwan (China); Lin, C.-W. [Graduate Institute of Pharmacy, School of Pharmacy, Taipei Medical University, Taipei 110, Taiwan (China); Chiu, W.-T. [Department of Neurosurgery, Taipei Medical University-Wan Fang Hospital, Taipei, Taiwan (China); Lin, C.-H. [Graduate Institute of Medical Sciences, Taipei Medical University, Taipei 110, Taiwan (China)], E-mail: chlin@tmu.edu.tw; Chen, Y.-C. [Graduate Institute of Medical Sciences, Taipei Medical University, Taipei 110, Taiwan (China); Cancer Research Center and Orthopedics Research Center, Taipei Medical University Hospital, Taipei, Taiwan (China)], E-mail: yc3270@tmu.edu.tw

    2009-06-15

    In the present study, zinc protoporphyrin (ZnPP), but not ferric protoporphyrin (FePP), tin protoporphyrin (SnPP), or zinc chloride (ZnCl{sub 2}), at the doses of 0.5, 1, and 2 {mu}M, dose-dependently inhibited lipopolysaccharide- (LPS), lipoteichoic acid (LTA), and peptidoglycan (PGN)-induced inducible nitric oxide (iNOS) and nitric oxide (NO) production with an increase in heme oxygenase 1 (HO-1) protein in RAW264.7 macrophages in a serum-free condition. NO inhibition and HO-1 induction by ZnPP were blocked by the separate addition of fetal bovine serum (FBS) and bovine serum albumin (BSA). A decrease in the iNOS/NO ratio and an increase in HO-1 protein by ZnPP were identified in three different conditions including ZnPP pretreatment, ZnPP co-treatment, and ZnPP post-treatment with LPS and LTA. Activation of c-Jun N-terminal kinases (JNKs) and extracellular regulated kinases (ERKs) were detected in LPS-, LTA-, and PGN-treated RAW264.7 cells, and iNOS/NO production was blocked by adding the JNK inhibitor, SP600125, but not the ERK inhibitor, PD98059. However, ZnPP addition potentiated ERK and JNK protein phosphorylation stimulated by LPS, LTA, and PGN. Increases in total protein ubiquitination and ubiquitinated iNOS proteins were detected in ZnPP-treated macrophages elicited by LPS according to Western and immunoprecipitation/Western blotting assays, respectively. The decrease in LPS-induced iNOS protein by ZnPP was reversed by adding the proteasome inhibitors MG132 and lactacystin. The reduction in HO-1 protein induced by ZnPP via transfection of HO-1 small interfering RNA did not affect the inhibitory effect of ZnPP against LPS-induced iNOS/NO production and protein ubiquitination induced by ZnPP in macrophages. Data of the present study provide the first evidence to support ZnPP effectively inhibiting inflammatory iNOS/NO production through activation of protein ubiquitination in a HO-1-independent manner in macrophages.

  19. Inducible nitric oxide synthase is crucial for plasma cell survival

    PubMed Central

    Njau, Modesta N; Jacob, Joshy

    2015-01-01

    The viability of long-lived plasma cells is enhanced by the expression of inducible nitric oxide synthase, which relieves endoplasmic reticulum stress by triggering a response dependent on cGMP and protein kinase G. PMID:24549066

  20. Inhibition of endogenous heat shock protein 70 attenuates inducible nitric oxide synthase induction via disruption of heat shock protein 70/Na(+) /H(+) exchanger 1-Ca(2+) -calcium-calmodulin-dependent protein kinase II/transforming growth factor ?-activated kinase 1-nuclear factor-?B signals in BV-2 microglia.

    PubMed

    Huang, Chao; Lu, Xu; Wang, Jia; Tong, Lijuan; Jiang, Bo; Zhang, Wei

    2015-08-01

    Inducible nitric oxide synthase (iNOS) critically contributes to inflammation and host defense. The inhibition of heat shock protein 70 (Hsp70) prevents iNOS induction in lipopolysaccharide (LPS)-stimulated macrophages. However, the role and mechanism of endogenous Hsp70 in iNOS induction in microglia remains unclear. This study addresses this issue in BV-2 microglia, showing that Hsp70 inhibition or knockdown prevents LPS-induced iNOS protein expression and nitric oxide production. Real-time PCR experiments showed that LPS-induced iNOS mRNA transcription was blocked by Hsp70 inhibition. Further studies revealed that the inhibition of Hsp70 attenuated LPS-stimulated nuclear translocation and phosphorylation of nuclear factor (NF)-?B as well as the degradation of inhibitor of ?B (I?B)-? and phosphorylation of I?B kinase ? (IKK?). This prevention effect of Hsp70 inhibition on IKK?-NF-?B activation was found to be dependent on the Ca(2+) /calcium-calmodulin-dependent protein kinase II (CaMKII)/transforming growth factor ?-activated kinase 1 (TAK1) signals based on the following observations: 1) chelation of intracellular Ca(2+) or inhibition of CaMKII reduced LPS-induced increases in TAK1 phosphorylation and 2) Hsp70 inhibition reduced LPS-induced increases in CaMKII/TAK1 phosphorylation, intracellular pH value, [Ca(2+) ]i , and CaMKII/TAK1 association. Mechanistic studies showed that Hsp70 inhibition disrupted the association between Hsp70 and Na(+) /H(+) exchanger 1 (NHE1), which is an important exchanger responsible for Ca(2+) influx in LPS-stimulated cells. These studies demonstrate that the inhibition of endogenous Hsp70 attenuates the induction of iNOS, which likely occurs through the disruption of NHE1/Hsp70-Ca(2+) -CaMKII/TAK1-NF-?B signals in BV-2 microglia, providing further insight into the functions of Hsp70 in the CNS. © 2015 Wiley Periodicals, Inc. PMID:25691123

  1. Polarized distribution of inducible nitric oxide synthase regulates activity in intestinal epithelial cells

    E-print Network

    Paris-Sud XI, Université de

    1 Polarized distribution of inducible nitric oxide synthase regulates activity in intestinal deoxycholate; iNOS, inducible nitric oxide synthase; IFN-, interferon-; IL-1 interleukin-1, IL-6, interleukin-6; NO, nitric oxide; TLR5, Toll-like receptor 5; TX-100, Triton X-100 Key words: Inducible nitric oxide

  2. Exercise training reverses age-induced inducible nitric oxide synthase upregulation 

    E-print Network

    Song, Wook

    2005-02-17

    EXERCISE TRAINING REVERSES AGE-INDUCED INDUCIBLE NITRIC OXIDE SYNTHASE UPREGULATION A Dissertation by WOOK SONG Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of DOCTOR OF PHILOSOPHY December 2003 Major Subject: Kinesiology EXERCISE TRAINING REVERSES AGE-INDUCED INDUCIBLE NITRIC OXIDE SYNTHASE UPREGULATION A Dissertation by WOOK SONG...

  3. Methanol extract of Ficus leaf inhibits the production of nitric oxide and proinflammatory cytokines in LPS-stimulated microglia via the MAPK pathway.

    PubMed

    Jung, Hyo Won; Son, Hye Young; Minh, Chau Van; Kim, Young Ho; Park, Yong-Ki

    2008-08-01

    Excessive production of inflammatory mediators, nitric oxide (NO) and proinflammatory cytokines from activated microglia has been implicated in neurodegeneration in human brain diseases. Recently, it seems possible that treatment with antiinflammatory agents, including Oriental medicinal plants, might delay the progression of neurodegeneration through the inhibition of microglial activation. The present study evaluated the effect of a methanol extract of Ficus religiosa leaf (MFL) on lipopolysaccharide (LPS)-induced production of NO and proinflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha), interleukin-beta (IL-1beta) and IL-6 in BV-2 cells, a mouse microglial line. MFL inhibited LPS-induced production of NO and proinflammatory cytokines in a dose-dependent manner. MFL also attenuated the expression of mRNA and proteins of inducible nitric oxide synthase (iNOS) and proinflammatory cytokines, suggesting the blockage of transcription levels, respectively. The molecular mechanism of MFL-mediated attenuation underlies the down-regulation of the extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK) signaling pathway, and suppresses the nuclear factor kappaB (NF-kappaB) activation. The results suggest that MFL exhibits antiinflammatory properties in LPS-induced activation of BV2 microglial cells, and that might have a therapeutic potential for various neurodegenerative diseases. PMID:18546149

  4. Overproduction of nitric oxide by endothelial cells and macrophages contributes to mitochondrial oxidative stress in adrenocortical cells and adrenal insufficiency during endotoxemia.

    PubMed

    Wang, Chang-Nan; Duan, Guo-Li; Liu, Yu-Jian; Yu, Qing; Tang, Xiao-Lu; Zhao, Wei; Li, Xiao-Han; Zhu, Xiao-Yan; Ni, Xin

    2015-06-01

    We have recently demonstrated that lipopolysaccharide (LPS) causes mitochondrial oxidative stress and dysfunction in adrenal glands, thereby leading to adrenocortical insufficiency. Since nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) leads to mitochondrial damage in various tissues, the present study aims to investigate whether NO contributes to mitochondrial oxidative stress in adrenal cortex and adrenocortical insufficiency during endotoxemia. Systemic administration of LPS increased iNOS expression and NO production in adrenal glands of mice. The specific iNOS inhibitor 1400W significantly attenuated the LPS-induced mitochondrial superoxide production and dysfunction in adrenal glands, and reversed the LPS-induced adrenocortical hyporesponsiveness to adrenocorticotropic hormone (ACTH). In contrast, administration of the NO donor sodium nitroprusside (SNP) led to mitochondrial oxidative stress and dysfunction in adrenal glands, which resulted in a blunted corticosterone response to ACTH. Using double immunofluorescence staining for iNOS with the vascular endothelial cell marker CD31 or the macrophage marker CD68, we found that increased iNOS expression was found in vascular endothelial cells and macrophages, but not adrenocortical cells in the adrenal gland during endotoxemia. Administration of the hydrogen sulfide (H2S) donor GYY4137 inhibited NO production and reversed LPS-induced adrenocortical hyporesponsiveness. Our data suggest that overproduction of NO, which is mainly generated by endothelial cells and macrophages during endotoxemia, contributes to mitochondrial oxidative stress in adrenocortical cells and subsequently leads to adrenal insufficiency. PMID:25744413

  5. Role of nitric oxide in shiga toxin-2-induced premature delivery of dead fetuses in rats.

    PubMed

    Burdet, Juliana; Zotta, Elsa; Cella, Maximiliano; Franchi, Ana M; Ibarra, Cristina

    2010-01-01

    Shiga toxin-producing Escherichia coli (STEC) infections could be one of the causes of fetal morbimortality in pregnant women. The main virulence factors of STEC are Shiga toxin type 1 and/or 2 (Stx1, Stx2). We previously reported that intraperitoneal (i.p.) injection of rats in the late stage of pregnancy with culture supernatant from recombinant E. coli expressing Stx2 and containing lipopolysaccharide (LPS) induces premature delivery of dead fetuses. It has been reported that LPS may combine with Stx2 to facilitate vascular injury, which may in turn lead to an overproduction of nitric oxide (NO). The aim of this study was to evaluate whether NO is involved in the effects of Stx2 on pregnancy. Pregnant rats were i.p. injected with culture supernatant from recombinant E. coli containing Stx2 and LPS (sStx2) on day 15 of gestation. In addition, some rats were injected with aminoguanidine (AG), an inducible isoform inhibitor of NO synthase (iNOS), 24 h before and 4 h after sStx2 injection. NO production was measured by NOS activity and iNOS expression by Western blot analysis. A significant increase in NO production and a high iNOS expression was observed in placental tissues from rats injected with sStx2 containing 0.7 ng and 2 ng Stx2/g body weight and killed 12 h after injection. AG caused a significant reduction of sStx2 effects on the feto-maternal unit, but did not prevent premature delivery. Placental tissues from rats treated with AG and sStx2 presented normal histology that was indistinguishable from the controls. Our results reveal that Stx2-induced placental damage and fetus mortality is mediated by an increase in NO production and that AG is able to completely reverse the Stx2 damages in placental tissues, but not to prevent premature delivery, thus suggesting other mechanisms not yet determined could be involved. PMID:21206910

  6. Role of Nitric Oxide in Shiga Toxin-2-Induced Premature Delivery of Dead Fetuses in Rats

    PubMed Central

    Burdet, Juliana; Zotta, Elsa; Cella, Maximiliano; Franchi, Ana M.; Ibarra, Cristina

    2010-01-01

    Shiga toxin-producing Escherichia coli (STEC) infections could be one of the causes of fetal morbimortality in pregnant women. The main virulence factors of STEC are Shiga toxin type 1 and/or 2 (Stx1, Stx2). We previously reported that intraperitoneal (i.p.) injection of rats in the late stage of pregnancy with culture supernatant from recombinant E. coli expressing Stx2 and containing lipopolysaccharide (LPS) induces premature delivery of dead fetuses. It has been reported that LPS may combine with Stx2 to facilitate vascular injury, which may in turn lead to an overproduction of nitric oxide (NO). The aim of this study was to evaluate whether NO is involved in the effects of Stx2 on pregnancy. Pregnant rats were i.p. injected with culture supernatant from recombinant E. coli containing Stx2 and LPS (sStx2) on day 15 of gestation. In addition, some rats were injected with aminoguanidine (AG), an inducible isoform inhibitor of NO synthase (iNOS), 24 h before and 4 h after sStx2 injection. NO production was measured by NOS activity and iNOS expression by Western blot analysis. A significant increase in NO production and a high iNOS expression was observed in placental tissues from rats injected with sStx2 containing 0.7 ng and 2 ng Stx2/g body weight and killed 12 h after injection. AG caused a significant reduction of sStx2 effects on the feto-maternal unit, but did not prevent premature delivery. Placental tissues from rats treated with AG and sStx2 presented normal histology that was indistinguishable from the controls. Our results reveal that Stx2-induced placental damage and fetus mortality is mediated by an increase in NO production and that AG is able to completely reverse the Stx2 damages in placental tissues, but not to prevent premature delivery, thus suggesting other mechanisms not yet determined could be involved. PMID:21206910

  7. Insulin inhibits inducible nitric oxide synthase in skeletal muscle cells

    Microsoft Academic Search

    S. Bédard; B. Marcotte; A. Marette

    1998-01-01

    Summary   Recent studies have shown that cytokines and endotoxins impair insulin-stimulated glucose transport by activating the expression\\u000a of inducible nitric oxide synthase (iNOS) and nitric oxide (NO) production in skeletal muscle cells. In this study, we investigated\\u000a whether iNOS induction is modulated by insulin in L6 myocytes. Long term exposure of muscle cells to tumour necrosis factor-?\\u000a (TNF-?), interferon-? (IFN-?)

  8. Ganoderma lucidum inhibits inducible nitric oxide synthase expression in macrophages

    Microsoft Academic Search

    Connie W. H. Woo; Ricky Y. K. Man; Yaw L. Siow; Patrick C. Choy; Eric W. Y. Wan; Chak S. Lau; Karmin O

    2005-01-01

    Nitric oxide (NO) is a principal mediator in many physiological and pathological processes. Overproduction of NO via the inducible nitric oxide synthase (iNOS) has cytotoxic effect through the formation of peroxynitrite with superoxide anion. The iNOS is mainly expressed in macrophages and is able to produce large amount of NO. The expression of iNOS is mainly regulated at the transcriptional

  9. Supercritical extract of Seabuckthorn Leaves (SCE200ET) inhibited endotoxemia by reducing inflammatory cytokines and nitric oxide synthase 2 expression.

    PubMed

    Jayashankar, Bindhya; Mishra, K P; Ganju, L; Singh, S B

    2014-05-01

    Endotoxins from infectious organisms lead to sepsis, a systemic inflammatory response, and a major cause of death. Numerous studies have shown the potential role of plants and plant-derived compounds in the suppression of LPS induced endotoxemia in vivo. In the present study, we have identified a plant namely Seabuckthorn (Hippophae rhamnoides L.) as a potent agent for the treatment of endotoxemia. The objective of the study was to investigate the influence of Supercritical Extract of Seabuckthorn Leaves (SCE200ET) and its active component Isorhamnetin (IR) on the LPS induced endotoxemia in Balb/c mice by measuring the level of nitric oxide (NO), TNF-? and IL-6. Expression of COX-2 and iNOS was measured to understand the involvement of various pathways in the mechanism of action of SCE200ET and IR. The results indicated that SCE200ET and IR inhibited LPS induced NO production by peritoneal macrophages. Cytokines mediated effector functions were influenced by the reduction of IL-6 and TNF-? production and CD40 expression was also markedly diminished in the extract or IR treated groups. In addition, the anti-inflammatory properties were further characterized by decreased expression of COX-2 and iNOS proteins. Fractionation and phytochemical analysis of the extract by RP-HPLC led to identification of isorhamnetin, as bioactive component. Thus, SCE200ET extract and its active component Isorhamnetin could be potential therapeutic agents for the treatment of endotoxin induced sepsis. PMID:24594274

  10. Ethanol extract of Magnolia officinalis prevents lipopolysaccharide-induced memory deficiency via its antineuroinflammatory and antiamyloidogenic effects.

    PubMed

    Lee, Young-Jung; Choi, Dong-Young; Yun, Yeo-Pyo; Han, Sang Bae; Kim, Hwan Mook; Lee, Kiho; Choi, Seok Hwa; Yang, Mhan-Pyo; Jeon, Hyun Soo; Jeong, Jea-Hwang; Oh, Ki-Wan; Hong, Jin Tae

    2013-03-01

    Magnolia bark contains several compounds such as magnolol, honokiol, 4-O-methylhonokiol, obovatol, and other neolignan compounds. These compounds have been reported to have various beneficial effects in various diseases. There is sufficient possibility that ethanol extract of Magnolia officinalis is more effective in amyloidogenesis via synergism of these ingredients. Neuroinflammation has been known to play a critical role in the pathogenesis of Alzheimer's disease (AD). We investigated whether the ethanol extract of M.?officinalis (10?mg/?kg in 0.05% ethanol) prevents memory dysfunction and amyloidogenesis in AD mouse model by intraperitoneal lipopolysaccharide (LPS, 250?µg/?kg/day for seven times) injection. We found that ethanol extract of M.?officinalis prevented LPS-induced memory deficiency as well as inhibited the LPS-induced elevation of inflammatory proteins, such as inducible nitric oxide synthase and cyclooxygenase 2, and activation of astrocytes and microglia. In particular, administration of M.?officinalis ethanol extract inhibited LPS-induced amyloidogenesis, which resulted in the inhibition of amyloid precursor protein, beta-site amyloid-precursor-protein-cleaving enzyme 1 and C99. Thus, this study shows that ethanol extract of M.?officinalis prevents LPS-induced memory impairment as well as amyloidogenesis via inhibition of neuroinflammation and suggests that ethanol extract of M.?officinalis might be a useful intervention for neuroinflammation-associated diseases such as AD. PMID:22628265

  11. Malabaricone C suppresses lipopolysaccharide-induced inflammatory responses via inhibiting ROS-mediated Akt/IKK/NF-?B signaling in murine macrophages.

    PubMed

    Kang, Jungwon; Tae, Nara; Min, Byung Sun; Choe, Jongseon; Lee, Jeong-Hyung

    2012-11-01

    Malabaricone C (MLB-C), isolated from nutmeg, is a phenolic diarylnonanoid that is known to exert a variety of pharmacological activities. In the present study, we investigated the molecular actions of MLB-C against lipopolysaccharide (LPS)-induced inflammatory responses in RAW264.7 cells and murine peritoneal macrophages. MLB-C inhibited the production of nitric oxide (NO), prostaglandin E(2) (PGE(2)), interleukin-6 (IL-6), and interferon-? (INF-?) in a dose-dependent manner. Consistent with NO and PGE(2) inhibition, MLB-C suppressed LPS-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression as well as the promoter activities of COX-2 and iNOS. MLB-C pretreatment prevented LPS-induced nuclear factor-kappa B (NF-?B) activation through the inhibition of phosphorylation of I?B kinase (IKK), phosphorylation and degradation of I?B?, and nuclear translocation of NF-?B. In addition, MLB-C blocked LPS-induced serine 536 phosphorylation and transcriptional activity of RelA/p65 subunit of NF-?B. Further study demonstrated that MLB-C inhibited LPS-induced Akt phosphorylation, which is an upstream activator of NF-?B, by reducing reactive oxygen species (ROS) accumulation, without affecting phosphorylation of mitogen-activated protein kinases (MAPKs). These findings indicate that MLB-C exerts an anti-inflammatory effect through the inhibition of NF-?B activation by inhibiting interconnected ROS/Akt/IKK/NF-?B signaling pathways. PMID:22917708

  12. Short Communication The nitric oxide synthase inhibitor l-NAME suppresses androgen-induced

    E-print Network

    Crews, David

    Short Communication The nitric oxide synthase inhibitor l-NAME suppresses androgen-induced male July 2005 Abstract The synthesis of nitric oxide by the enzyme nitric oxide synthase (NOS) is involved, suggesting that the central role of nitric oxide synthesis is conserved in this species. The deficit

  13. Inducible Nitric Oxide Synthase Mediates Retinal Apoptosis in Ischemic Proliferative Retinopathy

    E-print Network

    Boyer, Edmond

    Inducible Nitric Oxide Synthase Mediates Retinal Apoptosis in Ischemic Proliferative Retinopathy to be the leading mechanism in ischemic retinal degeneration. We showed recently that induc- ible nitric oxide and to improve its vascularization. Key words: inducible nitric oxide synthase; apoptosis; retina; knock-out mice

  14. Strategies for laser-induced fluorescence detection of nitric oxide in high-pressure flames.

    E-print Network

    Lee, Tonghun

    Strategies for laser-induced fluorescence detection of nitric oxide in high-pressure flames. III, and Ronald K. Hanson Laser-induced fluorescence LIF has proven a reliable technique for nitric oxide. Introduction Laser-induced fluorescence LIF is an important tool1­3 to help understand nitric oxide

  15. Endothelial Thrombomodulin Induces Ca2 Signals and Nitric

    E-print Network

    Paris-Sud XI, Université de

    Endothelial Thrombomodulin Induces Ca2 Signals and Nitric Oxide Synthesis through Epidermal Growth 6-CNRS, Paris 75014, France Endothelial membrane-bound thrombomodulin is a high affinity receptor) and to modulate G protein-coupled receptor signaling. Cul- tured human umbilical vein endothelial cells were

  16. Oral Administration of 2 -Docosahexaenoyl Lysophosphatidylcholine Displayed Anti-Inflammatory Effects on Zymosan A-Induced Peritonitis

    Microsoft Academic Search

    Nguyen Dang Hung; Mee Ree Kim; Dai-Eun Sok

    2011-01-01

    Lysophosphatidylcholines (lysoPCs) have been known to be bioactive lipid mediators, which take part in various biological\\u000a and pathological processes. In the present study, we examined the anti-inflammatory actions of 2-docosahexaenoyl lysophosphatidylcholine (2-docosahexaenoyl-lysoPC) in vitro as well as in vivo systems. When RAW 264.7 cells were treated with 2-docoshexaenoyl-lysoPC, a concentration-dependent decrease of LPS-induced formation of nitric oxide (NO), tumor necrosis

  17. UV Induced Oxidation of Nitric Oxide

    NASA Technical Reports Server (NTRS)

    Parrish, Clyde, F. (Inventor); Luecke, Dale E. (Inventor)

    2007-01-01

    Nitric oxide in a gaseous stream is converted to nitrogen dioxide using oxidizing species generated at least in part using in situ UV radiation sources. The sources of the oxidizing species include oxygen and/or hydrogen peroxide. The oxygen may be a component of the gaseous stream or added to the gaseous stream, preferably near a UV radiation source, and is converted to ozone by the UV irradiation. The hydrogen peroxide is decomposed through a combination of vaporization and UV irradiation. The hydrogen peroxide is preferably stored at stable concentration levels, i.e., approximately 50% by volume and increased in concentration in a continuous process preceding vaporization within the flow channel of the gaseous stream and in the presence of the UV radiation sources.

  18. Cellular/Molecular A Calcium-Induced Calcium Influx Factor, Nitric Oxide,

    E-print Network

    Newman, Eric A.

    Cellular/Molecular A Calcium-Induced Calcium Influx Factor, Nitric Oxide, Modulates the Refilling in astrocytes, we imaged the formation of nitric oxide in cultured murine cortical astrocytes using DAF-FM (4 concentrations of ATP induced a Ca2 -dependent production of nitric oxide. We then investigated the roles

  19. Nitric oxide inhibits lipopolysaccharide-induced apoptosis in pulmonary artery endothelial cells

    E-print Network

    Engelhardt, John F.

    Nitric oxide inhibits lipopolysaccharide-induced apoptosis in pulmonary artery endothelial cells. Billiar, Simon A. Watkins, and Bruce R. Pitt. Nitric oxide inhibits lipopolysaccharide- induced apoptosis defined. Nitric oxide (NO) is an important effector molecule in acute lung injury, with both cytotoxic

  20. Synergistic Cytokine-Induced Nitric Oxide Production in Human Alveolar Epithelial Cells

    E-print Network

    George, Steven C.

    Synergistic Cytokine-Induced Nitric Oxide Production in Human Alveolar Epithelial Cells Soonjo Kwon; interleukin-1 ; inter- feron- ; tumor necrosis factor- . Nitric oxide (NO) is a highly reactive and perva demonstrated the potential for human lung epithelial cells to express inducible nitric oxide syn- thase (i

  1. Heme Distortion Modulated by Ligand-Protein Interactions in Inducible Nitric Oxide Synthase

    E-print Network

    Yeh, Syun-Ru

    Heme Distortion Modulated by Ligand-Protein Interactions in Inducible Nitric Oxide Synthase David in Inducible Nitric Oxide Synthase Author to whom correspondence should be sent: Denis L. Rousseau Phone: (718 Biology, Inc. #12;2 ABSTRACT The catalytic center of nitric oxide synthase (NOS) consists of a thiolate

  2. The inhibitory effect of quercitrin gallate on iNOS expression induced by lipopolysaccharide in Balb/c mice.

    PubMed

    Jo, Hyun Ye; Kim, Youngsoo; Nam, Sang Yoon; Lee, Beom Jun; Kim, Yun Bae; Yun, Young Won; Ahn, Byeongwoo

    2008-09-01

    Quercetin 3-O-beta-(2(")-galloyl)-rhamnopyranoside (QGR) is a naturally occurring quercitrin gallate, which is a polyphenolic compound that was originally isolated from Persicaria lapathifolia (Polygonaceae). QGR has been shown to have an inhibitory effect on nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated macrophage RAW 264.7 cells. Therefore, this study was conducted to investigate the inhibitory effect of QGR on nitric oxide production and inducible nitric oxide synthases (iNOS) expression in LPS-stimulated Balb/c mice. To accomplish this, 10 mg/kg of QGR was administered via gavage once a day for 3 days. iNOS was then induced by intraperitoneal injection of LPS. Six hours after the LPS treatment the animals were sacrificed under ether anethesia. The serum levels of NO were then measured to determine if QGR exerted an inhibitory effect on NO production in vivo. LPS induced an approximately 6 fold increase in the expression of NO. However, oral administration of QGR reduced the LPS induced increase in NO by half. Furthermore, RT-PCR and western blot analysis revealed that the increased levels of iNOS expression that occurred in response to treatment with LPS were significantly attenuated in response to QGR pretreatment. Histologically, LPS induced the infiltration of polymorphonuclear neutrophils in portal veins and sinusoids and caused the formation of a large number of necrotic cells; however, pretreatment with QGR attenuated these LPS induced effects. Taken together, these results indicate that QGR inhibits iNOS expression in vivo as well as in vitro and has antiinflammatory potentials. PMID:18716446

  3. Altered immune responses in mice lacking inducible nitric oxide synthase

    Microsoft Academic Search

    Xiao-Qing Wei; I. G. Charles; Austin Smith; Jan Ure; Gui-Jie Feng; Fang-Ping Huang; Damo Xu; W. Muller; Salvador Moncada

    1995-01-01

    NITRIC oxide (NO) is important in many biological functions1-5. It is generated from L-arginine by the enzyme NO synthase (NOS). The cytokine-inducible NOS (iNOS) is activated by several immunological stimuli, leading to the production of large quantities of NO which can be cytotoxic6. To define the biological role of iNOS further, we generated iNOS mutant mice. These are viable, fertile

  4. Anandamide rescues retinal barrier properties in Müller glia through nitric oxide regulation.

    PubMed

    Krishnan, G; Chatterjee, N

    2015-01-22

    The blood retinal barrier (BRB) can mitigate deleterious immune response. Dysfunction at the BRB can affect disease progression. Under inflammatory conditions Müller glia produce increased pro-inflammatory factors, like nitric oxide (NO). In this study we describe molecular events at the Müller glia during inflammation which could affect inner BRB properties. Griess assay and 4,5-diaminofluorescein diacetate (DAF-2DA) time-lapse fluorescence were used to measure NO production. Western blot was used to analyze the expression of inducible nitric oxide synthase (iNOS) and mitogen-activated protein kinases (MAPK) components. Lucifer Yellow was used to measure permeability. Griess assay and DAF-2DA time-lapse fluorescence images revealed that lipopolysaccharide (LPS) induced inflammation and increased NO production. In parallel, changes were observed in tight junction proteins, zona occludens 1 (ZO-1), connexin 43 (Cx43), and permeability. This was mediated through activation of iNOS and mitogen-activated protein kinase phosphatase-1 (MKP-1), implicated in immune response. Endocannabinoids can exert a protective and anti-inflammatory effect. Exogenous arachidonoyl ethanolamide (AEA) inhibited NO generation and also abolished LPS-induced increase in permeability. Our work suggests that subtle changes in Müller glia function, which act as part of the BRB, could contribute to retinal health. AEA which can reduce inflammatory cytotoxicity has potential as treatment in several ocular manifestations where the integrity of the BRB is crucial. PMID:25453774

  5. FT-ICR Study of Reaction Induced Fragmentation of Silicon Clusters with Nitric Oxide

    E-print Network

    Maruyama, Shigeo

    FT-ICR Study of Reaction Induced Fragmentation of Silicon Clusters with Nitric Oxide Shigeo of small silicon cluster ions (Si n + : 20 n 29) with nitric oxide was studied by using the FT with argon, and were exposed to the reactant gas, nitric oxide, in the ICR cell. Results of reaction for all

  6. Nitric Oxide and Cyclic GMP Induce Vesicle Release at Drosophila Neuromuscular Junction

    E-print Network

    Menzel, Randolf - Institut für Biologie

    Nitric Oxide and Cyclic GMP Induce Vesicle Release at Drosophila Neuromuscular Junction Britt, Bu¨ nteweg 17d, D-30559 Hannover, Germany Accepted 5 January 1999 ABSTRACT: Nitric oxide (NO such as nitric oxide (NO) can serve as membrane-permeant messengers in the nervous sys- tem has added a novel

  7. Experimental evaluation of strategies for quantitative laser-induced-fluorescence imaging of nitric oxide

    E-print Network

    Lee, Tonghun

    Engineering Department, Stanford University, Stanford, CA 94305, USA Abstract Nitric oxide laser. All rights reserved. Keywords: Nitric oxide; Laser-induced fluorescence; NO reburn; Combustion,2]. A species of par- ticular concern for its harmful impact on the envi- ronment is nitric oxide (NO), whose

  8. Lipopolysaccharide-Induced Expression of Microsomal Prostaglandin E Synthase-1 Mediates Late-Phase PGE2 Production in Bone Marrow Derived Macrophages

    PubMed Central

    Xiao, Lei; Ornatowska, Magdalena; Zhao, Guiqing; Cao, Hongmei; Yu, Rui; Deng, Jing; Li, Yongchao; Zhao, Qiong; Sadikot, Ruxana T.; Christman, John W.

    2012-01-01

    Cyclooxygenase (COX)-2 expression and release of prostaglandins (PGs) by macrophages are consistent features of lipopolysaccharide (LPS)-induced macrophage inflammation. The two major PGs, PGE2 and PGD2, are synthesized by the prostanoid isomerases, PGE synthases (PGES) and PGD synthases (PGDS), respectively. Since the expression profile and the individual role of these prostanoid isomerases-mediated inflammation in macrophages has not been defined, we examined the LPS-stimulated PGs production pattern and the expression profile of their synthases in the primary cultured mouse bone marrow derived macrophages (BMDM). Our data show that LPS induced both PGE2 and PGD2 production, which was evident by ?8 hrs and remained at a similar ratio (?1?1) in the early phase (?12 hrs) of LPS treatment. However, PGE2 production continued increase further in the late phase (16–24 hrs); whereas the production of PGD2 remained at a stable level from 12 to 24 hrs post-treatment. In response to LPS-treatment, the expression of both COX-2 and inducible nitric oxide synthase (iNOS) was detected within 2 to 4 hrs; whereas the increased expression of microsomal PGES (mPGES)-1 and a myeloid cell transcription factor PU.1 did not appear until later phase (?12 hrs). In contrast, the expression of COX-1, hematopoietic-PGDS (H-PGDS), cytosolic-PGES (c-PGES), or mPGES-2 in BMDM was not affected by LPS treatment. Selective inhibition of mPGES-1 with either siRNA or isoform-selective inhibitor CAY10526, but not mPGES-2, c-PGES or PU.1, attenuated LPS-induced burst of PGE2 production indicating that mPGES-1 mediates LPS-induced PGE2 production in BMDM. Interestingly, selective inhibition of mPGES-1 was also associated with a decrease in LPS-induced iNOS expression. In summary, our data show that mPGES-1, but not mPGES-2 or c-PGES isomerase, mediates LPS-induced late-phase burst of PGE2 generation, and regulates LPS-induced iNOS expression in BMDM. PMID:23226252

  9. Arctigenin Protects against Lipopolysaccharide-Induced Pulmonary Oxidative Stress and Inflammation in a Mouse Model via Suppression of MAPK, HO-1, and iNOS Signaling.

    PubMed

    Zhang, Wen-Zhou; Jiang, Zheng-Kui; He, Bao-Xia; Liu, Xian-Ben

    2015-08-01

    Arctigenin, a bioactive component of Arctium lappa (Nubang), has anti-inflammatory activity. Here, we investigated the effects of arctigenin on lipopolysaccharide (LPS)-induced acute lung injury. Mice were divided into four groups: control, LPS, LPS?+?DMSO, and LPS?+?Arctigenin. Mice in the LPS?+?Arctigenin group were injected intraperitoneally with 50 mg/kg of arctigenin 1 h before an intratracheal administration of LPS (5 mg/kg). Lung tissues and bronchoalveolar lavage fluids (BALFs) were collected. Histological changes of the lung were analyzed by hematoxylin and eosin staining. Arctigenin decreased LPS-induced acute lung inflammation, infiltration of inflammatory cells into BALF, and production of pro-inflammatory cytokines. Moreover, arctigenin pretreatment reduced the malondialdehyde level and increased superoxide dismutase and catalase activities and glutathione peroxidase/glutathione disulfide ratio in the lung. Mechanically, arctigenin significantly reduced the production of nitric oxygen and inducible nitric oxygen synthase (iNOS) expression, enhanced the expression of heme oxygenase-1, and decreased the phosphorylation of mitogen-activated protein kinases (MAPKs). Arctigenin has anti-inflammatory and antioxidative effects on LPS-induced acute lung injury, which are associated with modulation of MAPK, HO-1, and iNOS signaling. PMID:25616905

  10. Comparative study of the high molecular mass fraction and low molecular mass fraction of Sho-saiko-to in a murine immunologically induced liver injury model.

    PubMed

    Nose, Mitsuhiko; Terawaki, Kiyoshi; Iwahashi, Naomi; Oguri, Kanayo; Ogihara, Yukio

    2002-01-01

    We compared the pharmacological actions of the high and low molecular mass fractions of Sho-saiko-to using a murine immunologically induced liver injury model to estimate the roles of these fractions in the expression of the pharmacological action. In a Bacillus Calmette-Guerin (BCG)/lipopolysaccharide (LPS)-induced liver injury model, Sho-saiko-to and both of its fractions significantly reduced the increases in the aminotranseferase levels in serum. They also reduced the increase in the nitric oxide (NOx) level in serum. On the other hand, Sho-saiko-to and its high molecular mass fraction suppressed the increase in plasma NOx level in an LPS-induced endotoxin shock model but its low molecular mass fraction did not. These results suggest the possibility that both fractions act hepatoprotectively in a different manner. We believe that these results can help to elucidate the mechanism of action of ingredients in Sho-saiko-to. PMID:11824559

  11. Oxidized low density lipoprotein suppresses lipopolysaccharide-induced inflammatory responses in microglia: Oxidative stress acts through control of inflammation

    SciTech Connect

    Kim, Ohn Soon [Department of Pharmacology, Ajou University School of Medicine, San 5, Wonchen-Dong, Youngtong-Gu, Gyunggi-Do, Suwon 442-721 (Korea, Republic of); Chronic Inflammatory Disease Research Center, Ajou University School of Medicine, Suwon (Korea, Republic of); Lee, Chang Seok [Department of Pharmacology, Ajou University School of Medicine, San 5, Wonchen-Dong, Youngtong-Gu, Gyunggi-Do, Suwon 442-721 (Korea, Republic of); Chronic Inflammatory Disease Research Center, Ajou University School of Medicine, Suwon (Korea, Republic of); Joe, Eun-hye [Department of Pharmacology, Ajou University School of Medicine, San 5, Wonchen-Dong, Youngtong-Gu, Gyunggi-Do, Suwon 442-721 (Korea, Republic of); Jou, Ilo [Department of Pharmacology, Ajou University School of Medicine, San 5, Wonchen-Dong, Youngtong-Gu, Gyunggi-Do, Suwon 442-721 (Korea, Republic of) and Chronic Inflammatory Disease Research Center, Ajou University School of Medicine, Suwon (Korea, Republic of)]. E-mail: jouilo@ajou.ac.kr

    2006-03-31

    Low density lipoprotein (LDL) is readily oxidized under certain conditions, resulting in the formation of oxidized LDL (oxLDL). Despite numerous in vitro reports that reveal the pathogenic role of oxidative stress, anti-oxidative strategies have underperformed in the clinic. In this study, we examine the role of oxLDL in brain inflammatory responses using cultured rat brain microglia. We demonstrate that oxLDL inhibits lipopolysaccharide (LPS)-induced inflammatory responses in these cells. It also decreases LPS-induced expression of inducible nitric oxide synthase and production of nitric oxide, and reduces LPS-induced secretion of tumor necrosis factor-{alpha} and monocyte chemoattractant protein-1. Oxysterols, known components of oxLDL and endogenous agonists of liver X receptor, can simulate the inhibitory effects of oxLDL in LPS-activated microglia. In addition, their inhibitory effects were mimicked by liver X receptor (LXR) agonists and potentiated by a retinoid X receptor agonist, suggesting these molecules heterodimerize to function as oxysterol receptors. Taken together, our results demonstrate that oxLDL inhibits LPS-induced inflammatory responses in brain microglia and that these inhibitory effects are mediated by oxysterols and, at least in part, by the nuclear receptor LXR. Our results suggest an additional mechanism of action for oxidative stress that acts indirectly via modulation of inflammatory responses. Although further studies are needed, these results answer in part the question of why anti-oxidative strategies have not been successful in clinical situations. Moreover, as brain inflammation participates in the initiation and progression of several neurodegenerative disorders, the present data provide information that should prove a useful guide for designing therapeutic strategies to combat oxidative brain diseases.

  12. Mifepristone-induced nitric oxide release and expression of nitric oxide synthases in the human cervix during early pregnancy

    Microsoft Academic Search

    Mervi Väisänen-Tommiska; Ralf Butzow; Olavi Ylikorkala; Tomi S. Mikkola

    2006-01-01

    BACKGROUND: Nitric oxide (NO) is a factor in cervical ripening, perhaps under the control of progesterone. We studied the effects of the antiprogesterone mifepristone on the release of NO and on the expression of inducible NO syn- thase (iNOS) and endothelial NO synthase (eNOS) in the uterine cervix of women in early pregnancy. METHODS: Thirteen women were treated with oral

  13. Regulation of the expression of inducible nitric oxide synthase.

    PubMed

    Pautz, Andrea; Art, Julia; Hahn, Susanne; Nowag, Sebastian; Voss, Cornelia; Kleinert, Hartmut

    2010-09-15

    Nitric oxide (NO) generated by the inducible isoform of nitric oxide synthase (iNOS) is involved in complex immunomodulatory and antitumoral mechanisms and has been described to have multiple beneficial microbicidal, antiviral and antiparasital effects. However, dysfunctional induction of iNOS expression seems to be involved in the pathophysiology of several human diseases. Therefore iNOS has to be regulated very tightly. Modulation of expression, on both the transcriptional and post-transcriptional level, is the major regulation mechanism for iNOS. Pathways resulting in the induction of iNOS expression vary in different cells or species. Activation of the transcription factors NF-kappaB and STAT-1alpha and thereby activation of the iNOS promoter seems to be an essential step for the iNOS induction in most human cells. However, at least in the human system, also post-transcriptional mechanisms involving a complex network of RNA-binding proteins build up by AUF1, HuR, KSRP, PTB and TTP is critically involved in the regulation of iNOS expression. Recent data also implicate regulation of iNOS expression by non-coding RNAs (ncRNAs). PMID:20438856

  14. Inducible Nitric Oxide Synthase Expression in Human Colorectal Cancer

    PubMed Central

    Cianchi, Fabio; Cortesini, Camillo; Fantappiè, Ornella; Messerini, Luca; Schiavone, Nicola; Vannacci, Alfredo; Nistri, Silvia; Sardi, Iacopo; Baroni, Gianna; Marzocca, Cosimo; Perna, Federico; Mazzanti, Roberto; Bechi, Paolo; Masini, Emanuela

    2003-01-01

    To investigate the potential involvement of the nitric oxide (NO) pathway in colorectal carcinogenesis, we correlated the expression and the activity of inducible nitric oxide synthase (iNOS) with the degree of tumor angiogenesis in human colorectal cancer. Tumor samples and adjacent normal mucosa were obtained from 46 surgical specimens. Immunohistochemical expression of iNOS, vascular endothelial growth factor (VEGF), and CD31 was analyzed on paraffin-embedded tissue sections. iNOS activity and cyclic GMP levels were assessed by specific biochemical assays. iNOS protein expression was determined by Western blot analysis. iNOS and VEGF mRNA levels were evaluated using Northern blot analysis. Both iNOS and VEGF expressions correlated significantly with intratumor microvessel density (rs = 0.31, P = 0.02 and rs = 0.67, P < 0.0001, respectively). A significant correlation was also found between iNOS and VEGF expression (P = 0.001). iNOS activity and cyclic GMP production were significantly higher in the cancer specimens than in the normal mucosa (P < 0.0001 and P < 0.0001, respectively), as well as in metastatic tumors than in nonmetastatic ones (P = 0.002 and P = 0.04, respectively). Western and Northern blot analyses confirmed the up-regulation of the iNOS protein and gene in the tumor specimens as compared with normal mucosa. NO seems to play a role in colorectal cancer growth by promoting tumor angiogenesis. PMID:12598314

  15. Dried Ginger (Zingiber officinalis) Inhibits Inflammation in a Lipopolysaccharide-Induced Mouse Model.

    PubMed

    Choi, You Yeon; Kim, Mi Hye; Hong, Jongki; Kim, Sung-Hoon; Yang, Woong Mo

    2013-01-01

    Objectives. Ginger rhizomes have a long history of human use, especially with regards to their anti-inflammatory properties. However, the mechanisms by which ginger acts on lipopolysaccharide-(LPS-)induced inflammation have not yet been identified. We investigated the anti-inflammatory effects of dried Zingiber officinalis (DZO) on LPS-induced hepatic injury. Methods. ICR mice were given a DZO water extract (100, 1000?mg/kg) orally for three consecutive days. On the third day, they were administered by LPS intraperitoneally. To investigate the anti-inflammatory effects of DZO, histological, cytokine expression, and protein factor analyses were performed. Results. Oral administration of DZO significantly reduced pathological changes in the liver and proinflammatory cytokines including interferon-(IFN-) ? and interleukin-(IL-)6 in the serum. In addition, DZO inhibited LPS-induced NF- ? B activation by preventing degradation of the I ? B- ? , as well as the phosphorylation of ERK1/2, SAPK/JNK, and p38 MAPKs. These were associated with a decrease in the expression of inducible nitric oxide synthase (iNOS) and cyclooxyenase-2 (COX-2). Conclusions. Our data provide evidence for the hepatoprotective mechanisms of DZO as an anti-inflammatory effect. Furthermore, use of DZO to treat could provide therapeutic benefits in clinical settings. PMID:23935687

  16. Dietary selenium deficiency exacerbates lipopolysaccharide-induced inflammatory response in mouse mastitis models.

    PubMed

    Wei, Zhengkai; Yao, Minjun; Li, Yimeng; He, Xuexiu; Yang, Zhengtao

    2014-12-01

    Selenium (Se) is an essential micronutrient that plays a critical role in anti-inflammatory processes and antioxidant defense system. In this study, we investigated the effects of dietary selenium deficiency on lipopolysaccharide (LPS)-induced mastitis in mouse models. Se content in the liver was assessed by fluorescent atomic absorption spectrometry. Glutathione peroxidase (GPx) activity in the blood, myeloperoxidase (MPO) activity, tumor necrosis actor alpha (TNF-?), and interleukin (IL)-1? in the supernatant of the mammary tissue were determined according to the corresponding kits. Cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expressions were evaluated by Western blotting. The results showed that the Se-deficient mouse model was successfully replicated, and selenium deficiency exacerbated mammary gland histopathology, increased the expressions of TNF-? and IL-1?, and facilitated the activation of iNOS and COX-2 in LPS-induced mouse mastitis. In conclusion, our studies demonstrated that selenium deficiency resulted in more severe inflammatory response in LPS-induced mouse mastitis. PMID:24844733

  17. Dried Ginger (Zingiber officinalis) Inhibits Inflammation in a Lipopolysaccharide-Induced Mouse Model

    PubMed Central

    Choi, You Yeon; Kim, Mi Hye; Hong, Jongki; Kim, Sung-Hoon

    2013-01-01

    Objectives. Ginger rhizomes have a long history of human use, especially with regards to their anti-inflammatory properties. However, the mechanisms by which ginger acts on lipopolysaccharide-(LPS-)induced inflammation have not yet been identified. We investigated the anti-inflammatory effects of dried Zingiber officinalis (DZO) on LPS-induced hepatic injury. Methods. ICR mice were given a DZO water extract (100, 1000?mg/kg) orally for three consecutive days. On the third day, they were administered by LPS intraperitoneally. To investigate the anti-inflammatory effects of DZO, histological, cytokine expression, and protein factor analyses were performed. Results. Oral administration of DZO significantly reduced pathological changes in the liver and proinflammatory cytokines including interferon-(IFN-)? and interleukin-(IL-)6 in the serum. In addition, DZO inhibited LPS-induced NF-?B activation by preventing degradation of the I?B-?, as well as the phosphorylation of ERK1/2, SAPK/JNK, and p38 MAPKs. These were associated with a decrease in the expression of inducible nitric oxide synthase (iNOS) and cyclooxyenase-2 (COX-2). Conclusions. Our data provide evidence for the hepatoprotective mechanisms of DZO as an anti-inflammatory effect. Furthermore, use of DZO to treat could provide therapeutic benefits in clinical settings. PMID:23935687

  18. Lovastatin and phenylacetate inhibit the induction of nitric oxide synthase and cytokines in rat primary astrocytes, microglia, and macrophages.

    PubMed Central

    Pahan, K; Sheikh, F G; Namboodiri, A M; Singh, I

    1997-01-01

    This study explores the role of mevalonate inhibitors in the activation of NF-kbeta and the induction of inducible nitric oxide synthase (iNOS) and cytokines (TNF-alpha, IL-1beta, and IL-6) in rat primary astrocytes, microglia, and macrophages. Lovastatin and sodium phenylacetate (NaPA) were found to inhibit LPS- and cytokine-mediated production of NO and expression of iNOS in rat primary astrocytes; this inhibition was not due to depletion of end products of mevalonate pathway (e.g., cholesterol and ubiquinone). Reversal of the inhibitory effect of lovastatin on LPS-induced iNOS expression by mevalonate and farnesyl pyrophosphate and reversal of the inhibitory effect of NaPA on LPS-induced iNOS expression by farnesyl pyrophosphate, however, suggests a role of farnesylation in the LPS-mediated induction of iNOS. The inhibition of LPS-mediated induction of iNOS by FPT inhibitor II, an inhibitor of Ras farnesyl protein transferase, suggests that farnesylation of p21(ras) or other proteins regulates the induction of iNOS. Inhibition of LPS-mediated activation of NF-kbeta by lovastatin, NaPA, and FPT inhibitor II in astrocytes indicates that the observed inhibition of iNOS expression is mediated via inhibition of NF-kbeta activation. In addition to iNOS, lovastatin and NaPA also inhibited LPS-induced expression of TNF-alpha, IL-1beta, and IL-6 in rat primary astrocytes, microglia, and macrophages. This study delineates a novel role of the mevalonate pathway in controlling the expression of iNOS and different cytokines in rat astrocytes, microglia, and macrophages that may be important in developing therapeutics against cytokine- and NO-mediated neurodegenerative diseases. PMID:9389730

  19. Role of inducible nitric oxide synthase in trinitrobenzene sulphonic acid induced colitis in mice

    Microsoft Academic Search

    D-M McCafferty; M Miampamba; E Sihota; K A Sharkey; P Kubes

    1999-01-01

    BACKGROUNDStudies using inhibitors of nitric oxide synthase (NOS) to date are inconclusive regarding the role of inducible NOS (iNOS) in intestinal inflammation.AIMS(1) To examine the role of iNOS in the development of chronic intestinal inflammation; (2) to identify the cellular source(s) of iNOS.METHODSColitis was induced by an intrarectal instillation of trinitrobenzene sulphonic acid (TNBS, 60 mg\\/ml, 30% ethanol), in wild

  20. Nitric Oxide Production During Endotoxin-Induced Mastitis in the Cow1

    Microsoft Academic Search

    L. Bouchard; S. Blais; C. Desrosiers; X. Zhao; P. Lacasse

    1999-01-01

    Nitric oxide production was measured during endo- toxin-induced mastitis. One hour after morning milk- ing, the right hind quarters of 15 cows were infused with saline containing Escherichia coli endotoxin. Left hind control quarters were infused with saline only. At varying intervals before and after infusion, diagnostic markers of mastitis were recorded and nitric oxide pro- duction was evaluated by

  1. Effects of resveratrol and its derivatives on lipopolysaccharide-induced microglial activation and their structure-activity relationships.

    PubMed

    Meng, Xue-Lian; Yang, Jing-Yu; Chen, Guo-Liang; Wang, Li-Hui; Zhang, Li-Jia; Wang, Shu; Li, Jie; Wu, Chun-Fu

    2008-07-10

    The inhibitory effects of 21 resveratrol derivatives on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in microglia and their structure-activity relationships were studied. It was found, for the first time, that certain resveratrol derivatives that have 3,5-dimethoxyl groups in the A-ring, such as (E)-4-(3,5-dimethoxystyryl)phenol (pterostilbene, compound 2), or have substituted the B-ring of resveratrol with quinolyl, such as (E)-5-[2-(quinolin-4-yl)vinyl]benzene-1,3-diol (compound 18) and (E)-4-(3,5-dimethoxystyryl)quinoline (compound 19), strongly inhibited NO production. Compounds 2, 18, and 19 reduced LPS-induced protein and mRNA expression of inducible NO synthase (iNOS), but did not display direct NO-scavenging activity up to 30 microM in sodium nitroprusside (SNP) solution. Moreover, compounds 2, 18, and 19 could also significantly inhibit the production of TNF-alpha by LPS-activated microglia. Further studies revealed that compounds 2, 18, and 19 inhibited LPS-induced NO and TNF-alpha production in microglia by blocking IkappaBalpha phosphorylation and degradation. The potent inhibitory effects of compounds 2, 18, and 19 on microglial activation suggest their potential for treatment of neurodegenerative diseases accompanied by microglial activation. PMID:18513711

  2. Inducible nitric oxide synthase promoter polymorphism in human brucellosis.

    PubMed

    Orozco, Gisela; Sánchez, Elena; López-Nevot, Miguel Angel; Caballero, Abelardo; Bravo, María José; Morata, Pilar; de Dios Colmenero, Juan; Alonso, Antonio; Martín, Javier

    2003-11-01

    Nitric oxide (NO), produced by the inducible nitric oxide synthase (NOS2) protein, is a defence mechanism against various pathogens, including bacteria of the genus Brucella. The aim of this study was to investigate the possible association between the NOS2 gene promoter polymorphism, TAAA(n) and CCTTT(n) microsatellites, and the predisposition to human brucellosis. We performed a case-control study in 85 patients with brucellosis and 100 healthy individuals, matched for age and sex, living in the same geographic area, in whom the NOS2 promoter was genotyped by using a polymerase chain reaction (PCR)-based method combined with fluorescent technology. No statistically significant differences were observed in the distribution of TAAA(n) alleles between the groups under study. When the overall NOS2 CCTTT(n) allele distribution of the brucellosis patients was compared with that of the control subjects, a significant skewing was observed (P = 0.04, by chi(2) test from 2 x 9 contingency table). Interestingly, we observed a trend towards Brucella infection protection with the 9 repeat (181 bp) allele (1.8% patients vs. 7.5% controls; P = 0.01, odds ratios = 0.22, 95% confidence interval = 0.05-0.83), which turned out to be non-significant after applying multiple testing. We concluded that the NOS2 microsatellite polymorphism might not have a major effect on brucellosis; nevertheless, the fact that a non-significant trend towards protection was detected in the CCTTT(n) alleles may be an indication for a follow-up study. PMID:14623011

  3. Therapeutic effect of C-phycocyanin extracted from blue green algae in a rat model of acute lung injury induced by lipopolysaccharide.

    PubMed

    Leung, Pak-On; Lee, Hao-Hsien; Kung, Yu-Chien; Tsai, Ming-Fan; Chou, Tz-Chong

    2013-01-01

    C-Phycocyanin (CPC), extracted from blue green algae, is a dietary nutritional supplement due to its several beneficial pharmacological effects. This study was conducted to evaluate whether CPC protects against lipopolysaccharide- (LPS-) induced acute lung injury (ALI) in rats. Rats were challenged with LPS (5?mg/kg body weight) intratracheally to induce ALI. After 3?h LPS instillation, rats were administrated with CPC (50?mg/kg body weight, i.p.) for another 3?h. Our results showed that posttreatment with CPC significantly inhibited LPS-induced elevation of protein concentration, nitrite/nitrate level, release of proinflammatory cytokines, the number of total polymorphonuclear cells in bronchoalveolar lavage fluid, and lung edema evidenced by decrease of lung wet/dry weight ratio accompanied by a remarkable improvement of lung histopathological alterations. Furthermore, CPC significantly attenuated LPS-induced myeloperoxidase activity, O2 (-) formation, expression of inducible nitric oxide synthase, and cyclooxygenase-2 as well as nuclear factor-kappa B (NF- ? B) activation in lungs. Additionally, CPC significantly downregulated proapoptotic proteins such as caspase-3 and Bax, but upregulated antiapoptotic proteins such as Bcl-2 and Bcl-XL in lungs exposed to LPS. These findings indicate that CPC could be potentially useful for treatment of LPS-related ALI by inhibiting inflammatory responses and apoptosis in lung tissues. PMID:23573157

  4. Potential involvement of nitric oxide synthase but not inducible nitric oxide synthase in the development of experimental corneal neovascularization

    PubMed Central

    Chen, Yuan; Liu, Gao-Qin; Lu, Pei-Rong

    2011-01-01

    AIM To investigate the effect of nitric oxide and its synthetase on experimental corneal neovascularization (CRNV). METHODS CRNV was induced by alkali injury in mice, nitric oxide synthetase (NOS) was inhibited by NG-nitro-L-arginine (L-NAME) and inducible nitric oxide synthetase (iNOS) was inhibited by aminoguanidine hemisulfate salt (AG). The inhibitory effect was detected at day 2 and 4 after corneal alkali injury by reverse transcription polymerase chain reaction (RT-PCR). CRNV was compared between the control and the treated mice by microscopic observation and corneal whole mount CD31 immunostaining. RESULTS The inhibition of L-NAME to NOS and AG to iNOS after corneal injury was confirmed by RT-PCR (P<0.05). Compared with control mice, L-NAME treated mice exhibited significantly decreased CRNV areas (P<0.05). In contrast, AG treatment failed to attenuate alkali induced CRNV (P>0.05). CONCLUSION Our findings suggest that NOS but not iNOS plays a critical role in alkali injury induced CRNV. PMID:22553677

  5. Somatostatin prevents lipopolysaccharide-induced neurodegeneration in the rat substantia nigra by inhibiting the activation of microglia

    PubMed Central

    BAI, LIJUAN; ZHANG, XIQUE; LI, XIAOHONG; LIU, NA; LOU, FAN; MA, HONGLEI; LUO, XIAOGUANG; REN, YAN

    2015-01-01

    Somatostatin (SST) is a neuromodulator which is abundant throughout the central nervous system (CNS) and has a crucial role in neurodegenerative disorders. However, little is known about the effects and mechanisms of SST in dopaminergic (DA) neurons in the context of Parkinson’s disease (PD). In the present study, a model of PD was generated by injecting lipopolysaccharide (LPS) into the substantia nigra (SN) of rats in order to investigate the effects of SST on LPS-induced degeneration of DA in vivo. Intramural injection of LPS resulted in a significant loss of DA neurons, while reduction of neuronal death by SST pretreatment was confirmed using immunohistochemical staining for tyrosine hydroxylase and Nissl. In parallel, immunohistochemical detection of OX-42 and hydroethidine staining were employed to determine the activation of microglia and production of reactive oxygen species (ROS), respectively. It was found that SST inhibited the LPS-induced microglial activity and ROS production. ELISA revealed a decreased production of pro-inflammatory mediators, including tumor necrosis factor-?, interleukin-1? and prostaglandin E2 when SST was administered prior to LPS treatment. Western blot analysis showed that LPS-induced expression of inducible nitric oxide synthase, cyclooxygenase-2 and nuclear factor ?B (NF-?B) p-p65 was attenuated by administration of SST prior to LPS application. The results indicated that LPS-induced loss of nigral DA neurons was inhibited by SST and the observed effects of SST on neuroprotection were associated with suppression of microglial activation and the NF-?B pathway, ensuing decreases of neuroinflammation and oxidative stress. The present study therefore suggested that SST is beneficial for treating neurodegenerative diseases, such as PD, through inhibiting the activation of microglia. PMID:25777539

  6. PKC412 (CGP41251) modulates the proliferation and lipopolysaccharide-induced inflammatory responses of RAW 264.7 macrophages

    SciTech Connect

    Miyatake, Katsutoshi [Department of Orthopedics, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima (Japan); Institute for Genome Research, The University of Tokushima, Tokushima (Japan); Inoue, Hiroshi [Institute for Genome Research, The University of Tokushima, Tokushima (Japan)]. E-mail: hinoue@genome.tokushima-u.ac.jp; Hashimoto, Kahoko [Department of Life and Environmental Sciences, Faculty of Engineering, Chiba Institute of Technology, Chiba (Japan); Takaku, Hiroshi [Department of Life and Environmental Sciences, Faculty of Engineering, Chiba Institute of Technology, Chiba (Japan); Takata, Yoichiro [Department of Orthopedics, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima (Japan); Nakano, Shunji [Department of Orthopedics, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima (Japan); Yasui, Natsuo [Department of Orthopedics, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima (Japan); Itakura, Mitsuo [Institute for Genome Research, The University of Tokushima, Tokushima (Japan)

    2007-08-17

    PKC412 (CGP41251) is a multitarget protein kinase inhibitor with anti-tumor activities. Here, we investigated the effects of PKC412 on macrophages. PKC412 inhibited the proliferation of murine RAW 264.7 macrophages through induction of G2/M cell cycle arrest and apoptosis. At non-toxic drug concentrations, PKC412 significantly suppressed the lipopolysaccharide (LPS)-induced release of TNF-{alpha} and nitric oxide, while instead enhancing IL-6 secretion. PKC412 attenuated LPS-induced phosphorylations of MKK4 and JNK, as well as AP-1 DNA binding activities. Furthermore, PKC412 suppressed LPS-induced Akt and GSK-3{beta} phosphorylations. These results suggest that the anti-proliferative and immunomodulatory effects of PKC412 are, at least in part, mediated through its interference with the MKK4/JNK/AP-1 and/or Akt/GSK-3{beta} pathways. Since macrophages contribute significantly to the development of both acute and chronic inflammation, PKC412 may have therapeutic potential and applications in treating inflammatory and/or autoimmune diseases.

  7. Arginase attenuates inhibitory nonadrenergic noncholinergic nerve-induced nitric oxide generation and airway smooth muscle relaxation

    Microsoft Academic Search

    Harm Maarsingh; Marieke A Tio; Johan Zaagsma; Herman Meurs

    2005-01-01

    BACKGROUND: Recent evidence suggests that endogenous arginase activity potentiates airway responsiveness to methacholine by attenuation of agonist-induced nitric oxide (NO) production, presumably by competition with epithelial constitutive NO synthase for the common substrate, L-arginine. Using guinea pig tracheal open-ring preparations, we now investigated the involvement of arginase in the modulation of neuronal nitric oxide synthase (nNOS)-mediated relaxation induced by inhibitory

  8. Diosgenin down-regulates NF-?B p65/p50 and p38MAPK pathways and attenuates acute lung injury induced by lipopolysaccharide in mice.

    PubMed

    Gao, Mengyu; Chen, Ling; Yu, Haixiang; Sun, Qi; Kou, Junping; Yu, Boyang

    2013-02-01

    Diosgenin (Dio), a major active component of steroidal sapogenin of the traditional Chinese herb Dioscorea zingiberensis C.H.Wright, shows various activities including anti-inflammatory, anti-thrombotic activities, anti-cancer properties etc. In the present study, we found that diosgenin significantly suppressed the phosphorylation of lung NF-?B p50/p65 and MAPK/p38 in lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice, when given orally at doses of 0.1, 1.0 and 10mg/kg 1h prior to LPS challenge (30 mg/kg, intravenous injection). Moreover, diosgenin attenuated the lung histopathological changes such as pulmonary edema, coagulation and infiltration of inflammatory cells. In addition, diosgenin significantly decreased the lung wet to dry weight (W/D) ratio and nitrite/nitrate content at three doses, and also markedly inhibited LPS-induced body temperature decrease and nitrite/nitrate elevation in plasma. Besides, diosgenin could significantly suppress activation of NF-?B p65/p50, p38 and expression of inducible nitric oxide synthase (iNOS) in LPS-induced THP-1 cells. Our findings indicate the potential application of diosgenin for ALI treatment. PMID:23246979

  9. Role of inducible nitric oxide synthase pathway on methotrexate-induced intestinal mucositis in rodents

    PubMed Central

    2011-01-01

    Background Methotrexate treatment has been associated to intestinal epithelial damage. Studies have suggested an important role of nitric oxide in such injury. The aim of this study was to investigate the role of nitric oxide (NO), specifically iNOS on the pathogenesis of methotrexate (MTX)-induced intestinal mucositis. Methods Intestinal mucositis was carried out by three subcutaneous MTX injections (2.5 mg/kg) in Wistar rats and in inducible nitric oxide synthase knock-out (iNOS-/-) and wild-type (iNOS+/+) mice. Rats were treated intraperitoneally with the NOS inhibitors aminoguanidine (AG; 10 mg/Kg) or L-NAME (20 mg/Kg), one hour before MTX injection and daily until sacrifice, on the fifth day. The jejunum was harvested to investigate the expression of Ki67, iNOS and nitrotyrosine by immunohistochemistry and cell death by TUNEL. The neutrophil activity by myeloperoxidase (MPO) assay was performed in the three small intestine segments. Results AG and L-NAME significantly reduced villus and crypt damages, inflammatory alterations, cell death, MPO activity, and nitrotyrosine immunostaining due to MTX challenge. The treatment with AG, but not L-NAME, prevented the inhibitory effect of MTX on cell proliferation. MTX induced increased expression of iNOS detected by immunohistochemistry. MTX did not cause significant inflammation in the iNOS-/- mice. Conclusion These results suggest an important role of NO, via activation of iNOS, in the pathogenesis of intestinal mucositis. PMID:21846355

  10. EXOGENOUS NITRIC OXIDE INDUCES PROTECTION DURING HEMORRHAGIC SHOCK

    PubMed Central

    Cabrales, Pedro; Tsai, Amy G.; Intaglietta, Marcos

    2009-01-01

    This study analyzed the systemic and microvascular hemodynamic changes related to increased nitric oxide (NO) availability during the early phase of hemorrhagic shock. Hemodynamic responses to hemorrhagic shock were studied in the hamster window chamber. Exogenous NO was administered in the form of nitrosothiols (nitrosylated glutathione, GSNO) and was given prior the onset of hemorrhage. Moderate hemorrhage was induced by arterial controlled bleeding of 50% of the blood volume, and the hypovolemic shock was followed over 90 min. Animals pre-treated with GSNO maintained systemic and microvascular conditions during hypovolemic hemorrhagic shock, when compared to animal treated with glutathione (GSH) or the sham group. Low concentrations of NO released during the early phase of hypovolemic shock from GSNO mitigated arteriolar vasoconstriction, increased capillary perfusion and venous return, and improved cardiac function (recovered of blood pressure and stabilized heart rate). GSNO's effect on resistance vessels influenced intravascular pressure redistribution and blood flow, preventing tissue ischemia. In conclusion, increases in NO availability during the early phase of hypovolemic shock, could preserve cardiac function and microvascular perfusion, sustaining organ function. Direct translation into a clinical scenario may be limited, although the pathophysiological importance of NO in the early phase of hypovolemia is clearly highlighted here. PMID:19362408

  11. Regulation of Inducible Nitric Oxide Synthase Gene in Glial Cells

    PubMed Central

    Saha, Ramendra N.; Pahan, Kalipada

    2007-01-01

    Elevated levels of NO produced within the central nervous system (CNS) are associated with the pathogenesis of neuroinflammatory and neurodegenerative human diseases such as multiple sclerosis, HIV dementia, brain ischemia, trauma, Parkinson's disease, and Alzheimer's disease. Resident glial cells in the CNS (astroglia and microglia) express inducible nitric oxide synthase (iNOS) and produce high levels of NO in response to a wide variety of proinflammatory and degenerative stimuli. Although pathways resulting in the expression of iNOS may vary in two different glial cells of different species, the intracellular signaling events required for the expression of iNOS in these cells are slowly becoming clear. Various signaling cascades converge to activate several transcription factors that control the transcription of iNOS in glial cells. The present review summarizes different results and discusses current understandings about signaling mechanisms for the induction of iNOS expression in activated glial cells. A complete understanding of the regulation of iNOS expression in glial cells is expected to identify novel targets for therapeutic intervention in NO-mediated neurological disorders. PMID:16771683

  12. Continuous Nitric Oxide Synthesis by Inducible Nitric Oxide Synthase in Normal Human Airway Epithelium in vivo

    Microsoft Academic Search

    Fuhua H. Guo; Hilde R. de Raeve; Thomas W. Rice; Dennis J. Stuehr; Frederic B. J. M. Thunnissen; Serpil C. Erzurum

    1995-01-01

    Nitric oxide (NO) is an important mediator of inflammatory responses in the lung and a key regulator of bronchomotor tone. An airway NO synthase (NOS; EC 1.14.13.39) has been proposed as a source of endogenous NO in the lung but has not been clearly defined. Through molecular cloning, we conclusively demonstrate that NO synthesis in normal human airways is due

  13. Deregulation of Hepatic Insulin Sensitivity Induced by Central Lipid Infusion in Rats Is Mediated by Nitric Oxide

    E-print Network

    Routh, Vanessa H.

    by Nitric Oxide Nicolas Marsollier1 *, Nadim Kassis1 , Karima Mezghenna2 , Maud Soty3,4,5 , Xavier: We investigated here whether hypothalamic nitric oxide (NO) could mediate deleterious peripheral Sensitivity Induced by Central Lipid Infusion in Rats Is Mediated by Nitric Oxide. PLoS ONE 4(8): e6649. doi

  14. Inhibition of Inducible Nitric Oxide Synthase in Murine Visceral Larva Migrans: Effects on Lung and Liver Damage

    Microsoft Academic Search

    Cihan Demirci; Aysen Gargili; Handan Cetinkaya; Ilhan Uyaner; Basak Boynuegri; M. Koray Gumustas

    2006-01-01

    The roles of nitric oxide production and oxidative process were studied in mice infected with Toxocara canis and treated with aminoguanidine which is a specific inhibitor of inducible nitric oxide synthase (iNOS). Relations of nitric oxide synthase inhibition and tissue pathology were assessed by biochemical, histological and immunohistochemical methods. In experiments, Balb\\/c albino mice were inoculated with T. canis eggs

  15. Modified peptide nucleic acids are internalized in mouse macrophages RAW 264.7 and inhibit inducible nitric oxide synthase

    Microsoft Academic Search

    Sonia Scarfi; Marco Giovine; Anna Gasparini; Gianluca Damonte; Enrico Millo; Marina Pozzolini; Umberto Benatti

    1999-01-01

    Overexpression of inducible nitric oxide synthase causes the production of high levels of nitric oxide, which, under pathological conditions, leads to immunosuppression and tissue damage. The results recently obtained using peptide nucleic acids, rather than traditional oligonucleotides as antigen and antisense molecules, prompted us to test their efficacy in the regulation of nitric oxide production, thereby overcoming the obstacle of

  16. Signaling cascade that mediates endothelial nitric oxide synthase activation induced by atrial natriuretic peptide

    Microsoft Academic Search

    Rosana Elesgaray; Carolina Caniffi; Daniela Rodríguez Ierace; María Florencia Visintini Jaime; Andrea Fellet; Cristina Arranz

    2008-01-01

    Atrial natriuretic peptide (ANP) induces activation of nitric oxide-synthase (NOS). Aims: to identify the isoform of NOS involved in ANP effects, to study whether ANP modifies NOS expression and to investigate the signaling pathways and receptors involved in NOS stimulation. NOS activation induced by ANP would be mediated by endothelial NOS (eNOS) since neuronal or inducible NOS inhibition did not

  17. Role of nitric oxide in hematosuppression and benzene-induced toxicity

    SciTech Connect

    Laskin, D.L.; Heck, D.E.; Punjabi, C.J.; Laskin J.D. [Rutgers Univ., Piscataway, NJ (United States)]|[UMDNJ-Robert Wood Johnson Medical School, Piscataway, NJ (United States)

    1996-12-01

    It is becoming increasingly apparent that nitric oxide plays a multifunctional role in regulating inflammatory processes in the body. Although nitric oxide and its oxidation products are cytotoxic toward certain pathogens, they can also cause tissue injury and suppress proliferation. Cytokines and growth factors released at sites of inflammation or injury stimulate both immune and nonimmune cells to produce nitric oxide. Nowhere in the body is this more detrimental than in the bone marrow, for the continuous production of hematopoietic precursors is essential for normal blood cell maturation. Our laboratories have discovered that, in response to inflammatory mediators, bone marrow cells readily produce nitric oxide. Nitric oxide production is enhanced by hematopoietic growth factors including interleukin-3, macrophage colony stimulating factor, and granulocyte-macrophage colony-stimulating factor. When bone marrow cells produce nitric oxide, hematopoiesis is impaired, an effect that is potentiated by colony-stimulating factors. Treatment of mice with benzene, which suppresses bone marrow cell development, was found to markedly enhance the ability of bone marrow cells to produce nitric oxide in response to inflammatory mediators alone and in combination with hematopoietic growth factors. Taken together, these data suggest that nitric oxide may be an important mediator of benzene-induced bone marrow suppression. 38 refs., 3 figs.

  18. Dissecting structural and electronic effects in inducible nitric oxide synthase.

    PubMed

    Hannibal, Luciana; Page, Richard C; Haque, Mohammad Mahfuzul; Bolisetty, Karthik; Yu, Zhihao; Misra, Saurav; Stuehr, Dennis J

    2015-04-01

    Nitric oxide synthases (NOSs) are haem-thiolate enzymes that catalyse the conversion of L-arginine (L-Arg) into NO and citrulline. Inducible NOS (iNOS) is responsible for delivery of NO in response to stressors during inflammation. The catalytic performance of iNOS is proposed to rely mainly on the haem midpoint potential and the ability of the substrate L-Arg to provide a hydrogen bond for oxygen activation (O-O scission). We present a study of native iNOS compared with iNOS-mesohaem, and investigate the formation of a low-spin ferric haem-aquo or -hydroxo species (P) in iNOS mutant W188H substituted with mesohaem. iNOS-mesohaem and W188H-mesohaem were stable and dimeric, and presented substrate-binding affinities comparable to those of their native counterparts. Single turnover reactions catalysed by iNOSoxy with L-Arg (first reaction step) or N-hydroxy-L-arginine (second reaction step) showed that mesohaem substitution triggered higher rates of Fe(II)O? conversion and altered other key kinetic parameters. We elucidated the first crystal structure of a NOS substituted with mesohaem and found essentially identical features compared with the structure of iNOS carrying native haem. This facilitated the dissection of structural and electronic effects. Mesohaem substitution substantially reduced the build-up of species P in W188H iNOS during catalysis, thus increasing its proficiency towards NO synthesis. The marked structural similarities of iNOSoxy containing native haem or mesohaem indicate that the kinetic behaviour observed in mesohaem-substituted iNOS is most heavily influenced by electronic effects rather than structural alterations. PMID:25608846

  19. Negative Regulation by Phosphatidylinositol 3Kinase of Inducible Nitric Oxide Synthase Expression in Macrophages1

    Microsoft Academic Search

    Maria J. M. Diaz-Guerra; Antonio Castrillo; Paloma Martin-Sanz; Lisardo Bosca

    Triggering of the macrophage cell line RAW 264.7 with LPS promotes a transient activation of phosphatidylinositol 3-kinase (PI3-kinase). Incubation of activated macrophages with wortmannin and LY294002, two inhibitors of PI3-kinase, increased the amount of inducible nitric oxide synthase (iNOS) and the synthesis of nitric oxide. Treatment with wortmannin promoted a prolonged activation of NF-kB in LPS-treated cells as well as

  20. Molecular Mechanisms by Which Iron Induces Nitric Oxide Synthesis in Cultured Proximal Tubule Cells

    Microsoft Academic Search

    Liguang Chen; Yiping Wang; Lukas K. Kairaitis; Yang Wang; Bao-Hong Zhang; David C. H. Harris

    2001-01-01

    Nitric oxide (NO) levels are increased after exposure of cultured proximal tubule cells (PTC) to non-haem iron, potentially contributing to PTC injury in disease states associated with increased iron exposure, including proteinuric renal disease. The mechanisms underlying this observed increase were investigated. After 3 h exposure to 400 ?M nitrilotriacetate (NTA)-Fe, inducible nitric oxide synthase (iNOS) mRNA expression was significantly

  1. Homocysteine stimulates inducible nitric oxide synthase expression in macrophages: Antagonizing effect of ginkgolides and bilobalide

    Microsoft Academic Search

    Connie W. H. Woo; Filly Cheung; Vincent W. H. Chan; Yaw L. Siow; O Karmin

    2003-01-01

    Hyperhomocysteinemia is an independent risk factor for atherosclerotic diseases. Inducible nitric oxide synthase (iNOS) is mainly expressed in macrophages upon stimulation. Overproduction of nitric oxide (NO) by iNOS can exacerbate the development of atherosclerosis. Our previous studies demonstrated that the extract of ginkgo biloba leaves (EGb) inhibited the iNOS-mediated NO production in monocyte-derived macrophage. We also reported that homocysteine could

  2. Inhibitory constituents of Sophora tonkinensis on nitric oxide production in RAW 264.7 macrophages.

    PubMed

    Lee, Jin Woo; Lee, Ji Hoon; Lee, Chul; Jin, Qinghao; Lee, Dongho; Kim, Youngsoo; Hong, Jin Tae; Lee, Mi Kyeong; Hwang, Bang Yeon

    2015-02-15

    Bioactivity-guided fractionation of the MeOH extract from the roots of Sophora tonkinensis resulted in the isolation of a new pterocarpan glycoside (1) together with nine known compounds, maackiain (2), sophoranone (3), sophoranochromene (4), pinoresinol (5), syringaresinol (6), medioresinol (7), 4',7-dihydroxyflavone (8), calycosin (9), and genistein (10). The structure of the new compound was determined on the basis of spectroscopic analysis including NMR and CD data in combination with acid hydrolysis. Compounds 1-4 exhibited the inhibitory effects on LPS-induced nitric oxide production with IC50 values ranging from 13.6 to 33.0?M in RAW 264.7 macrophages. PMID:25592708

  3. Sesquiterpenes from the essential oil of Curcuma wenyujin and their inhibitory effects on nitric oxide production.

    PubMed

    Xia, Guiyang; Zhou, Li; Ma, Jianghao; Wang, Ying; Ding, Liqin; Zhao, Feng; Chen, Lixia; Qiu, Feng

    2015-06-01

    Three new sesquiterpenes including a new elemane-type sesquiterpene, 5?H-elem-1,3,7,8-tetraen-8,12-olide (1), and two new carabrane-type sesquiterpenes, 7?,11-epoxy-6?-methoxy-carabrane-4,8-dione (2) and 8,11-epidioxy-8-hydroxy-4-oxo-6-carabren (3), together with eight known sesquiterpenes (4-11) were isolated from Curcuma wenyujin Y. H. Chen et C. Ling. Their structures were elucidated based on extensive spectroscopic analyses. A possible biogenetic scheme for the related compounds was postulated. All of the isolated compounds were tested for inhibitory activity against LPS-induced nitric oxide production in RAW 264.7 macrophages. Meanwhile, preliminary structure-activity relationships for these compounds are discussed. PMID:25819782

  4. Imaging Pulmonary Inducible Nitric Oxide Synthase Expression with PET

    PubMed Central

    Huang, Howard J.; Isakow, Warren; Byers, Derek E.; Engle, Jacquelyn T.; Griffin, Elizabeth A.; Kemp, Debra; Brody, Steven L.; Gropler, Robert J.; Miller, J. Philip; Chu, Wenhua; Zhou, Dong; Pierce, Richard A.; Castro, Mario; Mach, Robert H.; Chen, Delphine L.

    2015-01-01

    Inducible nitric oxide synthase (iNOS) activity increases in acute and chronic inflammatory lung diseases. Imaging iNOS expression may be useful as an inflammation biomarker for monitoring lung disease activity. We developed a novel tracer for PET that binds to iNOS in vivo, 18F-NOS. In this study, we tested whether 18F-NOS could quantify iNOS expression from endotoxin-induced lung inflammation in healthy volunteers. Methods Healthy volunteers were screened to exclude cardiopulmonary disease. Qualifying volunteers underwent a baseline, 1-h dynamic 18F-NOS PET/CT scan. Endotoxin (4 ng/kg) was then instilled bronchoscopically in the right middle lobe. 18F-NOS imaging was performed again approximately 16 h after endotoxin instillation. Radiolabeled metabolites were determined from blood samples. Cells recovered by bronchoalveolar lavage (BAL) after imaging were stained immunohistochemically for iNOS. 18F-NOS uptake was quantified as the distribution volume ratio (DVR) determined by Logan plot graphical analysis in volumes of interest placed over the area of endotoxin instillation and in an equivalent lung region on the left. The mean Hounsfield units (HUs) were also computed using the same volumes of interest to measure density changes. Results Seven healthy volunteers with normal pulmonary function completed the study with evaluable data. The DVR increased by approximately 30%, from a baseline mean of 0.42 ± 0.07 to 0.54 ± 0.12, and the mean HUs by 11% after endotoxin in 6 volunteers who had positive iNOS staining in BAL cells. The DVR did not change in the left lung after endotoxin. In 1 volunteer with low-level iNOS staining in BAL cells, the mean HUs increased by 7% without an increase in DVR. Metabolism was rapid, with approximately 50% of the parent compound at 5 min and 17% at 60 min after injection. Conclusion 18F-NOS can be used to image iNOS activity in acute lung inflammation in humans and may be a useful PET tracer for imaging iNOS expression in inflammatory lung disease. PMID:25525182

  5. Energetic particle-induced enhancements of stratospheric nitric acid

    NASA Technical Reports Server (NTRS)

    Aikin, Arthur C.

    1994-01-01

    Inclusion of complete ion chemistry in the calculation of minor species production during energetic particle deposition events leads to significant enhancement in the calculated nitric acid concentration during precipitation. An ionization rate of 1.2 x 10(exp 3)/cu cm/s imposed for 1 day increases HNO3 from 3 x 10(exp 5) to 6 x 10(exp 7)/cu cm at 50 km. With an ionization rate of 600 cu cm/s, the maximum HNO3 is 3 x 10(exp 7)/cu cm. Calculations which neglect negative ions predict the nitric acid will fall during precipitation events. The decay time for converting HNO3 into odd nitrogen and hydrogen is more than 1 day for equinoctial periods at 70 deg latitude. Examination of nitric acid data should yield important information on the magnitude and frequency of charged particle events.

  6. Time course and cellular localization of inducible nitric oxide synthases expression during cardiac allograft rejection

    Microsoft Academic Search

    Neil K Worrall; Thomas P Misko; Mitchell D Botney; Patrick M Sullivan; Jia-J Hui; Gloria M Suau; Pamela T Manning; T. Bruce Ferguson

    1999-01-01

    Background. We have demonstrated that inhibition of inducible nitric oxide synthase (NOS) ameliorated acute cardiac allograft rejection. This study determined the time course and cellular localization of inducible NOS expression during the histologic progression of unmodified acute rat cardiac allograft rejection.Methods. Tissue from syngeneic (ACI to ACI) and allogeneic (Lewis to ACI) transplants were harvested on postoperative days 3 through

  7. Effects of nitric oxide on gastric ulceration induced by nicotine and cold-restraint stress

    Microsoft Academic Search

    Bo-Sheng Qui; Qi-Bing Mei; Li Liu; Kam-Meng Tchou-Wong

    2004-01-01

    AIM: Stress induces gastric ulceration in human and experimental animals. People tend to smoke more cigarettes when under stress. Nitric oxide (NO) and nicotine have opposing effects on gastric integrity. The present study examined the possible therapeutic benefit of NO in nicotine- treated rats with stress-induced gastric ulceration. METHODS: Rats drank a nicotine solution while control rats drank tap water

  8. Nitrate Reductase is Responsible for Elicitin-induced Nitric Oxide Production in Nicotiana benthamiana

    Microsoft Academic Search

    Ayako Yamamoto-Katou; Shinpei Katou; Hirofumi Yoshioka; Noriyuki Doke; Kazuhito Kawakita

    2006-01-01

    ; Recent works have established a key role for nitric oxide (NO) in activating disease resistance in plants. Nitrate reductase (NR) is one of the enzymes that are capable of producing NO in plants. In a previous study, we reported that pathogen signals induce expression of NR genes in potato, suggesting the involvement of NR in NO produc- tion induced

  9. Korean Red Ginseng saponin fraction modulates radiation effects on lipopolysaccharide-stimulated nitric oxide production in RAW264.7 macrophage cells

    PubMed Central

    Lee, Young Ji; Han, Jeong Yoon; Lee, Chang Geun; Heo, Kyu; Park, Se Il; Park, Yoo Soo; Kim, Joong Sun; Yang, Kwang Mo; Lee, Ki-Ja; Kim, Tae-Hwan; Rhee, Man Hee; Kim, Sung Dae

    2014-01-01

    Background In previous work, we reported that Korean Red Ginseng saponin fraction (RGSF) showed anti-inflammatory activities in vitro and in vivo. Methods The present study investigated the radioprotective properties of RGSF by examining its effects on ionizing radiation (IR)-enhanced and lipopolysaccharide (LPS)-mediated inflammatory responses in murine macrophage cells. Results RGSF induced strong downregulation of IR-enhanced and LPS-induced proinflammatory responses such as nitric oxide (NO) production (Inhibitory Concentration 50 (IC50) = 5.1 ± 0.8 ?M) and interleukin-1? levels. RGSF was found to exert its radioprotective effects by inhibition of a signaling cascade that activated checkpoint kinase 2–nuclear factor-?B. In addition, RGSF strongly inhibited IR-enhanced LPS-induced expression of hemoxyganase-1, implying that the latter may be a potential target of RGSF. Conclusion Taken together, our data suggest that RGSF can be considered and developed for use as an effective radioprotective agent with minimal adverse effects. PMID:25378996

  10. LPS-Induced Genes in Intestinal Tissue of the Sea Cucumber Holothuria glaberrima

    Microsoft Academic Search

    Francisco Ramírez-Gómez; Pablo A. Ortiz-Pineda; Gabriela Rivera-Cardona; José E. García-Arrarás; Sebastian D. Fugmann

    2009-01-01

    Not Available Bibtex entry for this abstract Preferred format for this abstract (see Preferences) Find Similar Abstracts: Use: Authors Title Return: Query Results Return items starting with number Query Form Database: Astronomy Physics arXiv e-prints

  11. LPS-Induced Genes in Intestinal Tissue of the Sea Cucumber Holothuria glaberrima

    PubMed Central

    Ramírez-Gómez, Francisco; Ortiz-Pineda, Pablo A.; Rivera-Cardona, Gabriela; García-Arrarás, José E.

    2009-01-01

    Metazoan immunity is mainly associated with specialized cells that are directly involved with the immune response. Nevertheless, both in vertebrates and invertebrates other organs might respond to immune activation and participate either directly or indirectly in the ongoing immune process. However, most of what is known about invertebrate immunity has been restricted to immune effector cells and little information is available on the immune responses of other tissues or organs. We now focus on the immune reactions of the intestinal tissue of an echinoderm. Our study employs a non-conventional model, the echinoderm Holothuria glaberrima, to identify intestinal molecules expressed after an immune challenge presented by an intra-coelomic injection of lipopolysaccharides (LPS). The expression profiles of intestinal genes expressed differentially between LPS-injected animals and control sea water-injected animals were determined using a custom-made Agilent microarray with 7209 sea cucumber intestinal ESTs. Fifty (50) unique sequences were found to be differentially expressed in the intestine of LPS-treated sea cucumbers. Seven (7) of these sequences represented homologues of known proteins, while the remaining (43) had no significant similarity with any protein, EST or RNA database. The known sequences corresponded to cytoskeletal proteins (Actin and alpha-actinin), metabolic enzymes (GAPDH, Ahcy and Gnmt), metal ion transport/metabolism (major yolk protein) and defense/recognition (fibrinogen-like protein). The expression pattern of 11 genes was validated using semi-quantitative RT-PCR. Nine of these corroborated the microarray results and the remaining two showed a similar trend but without statistical significance. Our results show some of the molecular events by which the holothurian intestine responds to an immune challenge and provide important information to the study of the evolution of the immune response. PMID:19584914

  12. CpG DNA and LPS induce distinct patterns of activation in human monocytes

    Microsoft Academic Search

    G Hartmann; A M Krieg

    1999-01-01

    A specific set of immune functions is switched on in response to DNA containing unmethylated CpG dinucleotides in particular base contexts (‘CpG motifs’). Plasmids, viral vectors and antisense oligodeoxynucleotides used for DNA vaccination, gene replacement or gene blockade contain immunostimulatory CpG motifs which may have independent biological activity. Although the immune stimulatory effects of CpG motifs on murine cells are

  13. Previous Burn Injury Predisposes Mice to Lipopolysaccharide (LPS) Induced Changes in Glucose Metabolism

    PubMed Central

    Carter, Edward A.; Paul, Kasie; Barrow, Sandra A.; Fischman, Alan J.; Tompkins, Ronald G.

    2012-01-01

    In mice, it has been demonstrated that at 7 days after burn injury, injection of LPS is more lethal than the same dose at one day after injury. In the present study, we examined the effect of LPS injection to mice burned seven days previously on glucose metabolism (18FDG uptake) in vivo. CD-1 male mice (25-28 grams, Charles River breeding laboratories) were anesthetized, backs shaven, and subjected to dorsal full thickness burn on 25% total body surface area. Sham treated animals were used as controls. Six days after burn injury all mice were fasted overnight. One half of the burned and sham controls were subsequently injected i.p. with LPS (10 mg/kg, E. Coli). The remaining animals were injected with saline i.p. Two hours later all mice were injected i.v. with 50 ?Ci of 18F FDG. One hour later the animals were euthanized and biodistribution was measured. Tissues were weighed and radioactivity was measured with a well-type gamma counter. Results were expressed as %dose/gram tissue, mean ± SEM. The combination of burn 7 days previously and LPS significantly increased mortality compared animals with burn alone, LPS alone or sham controls. Burn injury seven days previously caused a significant reduction in 18FDG uptake by the brain compared to sham controls. The combination of LPS and burn injury seven days previously produced a significant increase in 18FDG uptake by brown adipose tissue (BAT) and heart compared with either treatment separately. LPS produced a significant increase in 18FDG uptake by lung, spleen and GI tract of the sham animals, changes that were different in mice burned 7 days previously and injected with LPS. The present results suggest that burn injury seven days previously predisposes mice to alterations in 18FDG uptake produced by LPS. These changes may relate in part, to the increased lethality of LPS injection in previously burned mice. PMID:22961012

  14. Fresh organically grown ginger ( Zingiber officinale): composition and effects on LPS-induced PGE 2 production

    Microsoft Academic Search

    Shivanand D. Jolad; R. Clark Lantz; Aniko M. Solyom; Guan Jie Chen; Robert B. Bates; Barbara N. Timmermann

    2004-01-01

    Gas chromatography in conjunction with mass spectrometry, a technique previously employed to analyze non-volatile pungent components of ginger extracts modified to trimethylsilyl derivatives, was applied successfully for the first time to analyze unmodified partially purified fractions from the dichloromethane extracts of organically grown samples of fresh Chinese white and Japanese yellow varieties of ginger, Zingiber officinale Roscoe (Zingiberaceae). This analysis

  15. AURANOFIN, AS AN ANTI-RHEUMATIC GOLD COMPOUND SUPPRESSES LPS-INDUCED HOMODIMERIZATION OF TLR4

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Toll-like receptors (TLRs), which are activated by invading microorganisms or endogenous molecules, evoke immune and inflammatory responses. TLR activation is closely linked to the development of many chronic inflammatory diseases including rheumatoid arthritis. Auranofin, an Au(I) compound, is a we...

  16. Skeletal Muscle PGC-1? Is Required for Maintaining an Acute LPS-Induced TNF? Response

    PubMed Central

    Olesen, Jesper; Larsson, Signe; Iversen, Ninna; Yousafzai, Simi; Hellsten, Ylva; Pilegaard, Henriette

    2012-01-01

    Many lifestyle-related diseases are associated with low-grade inflammation and peroxisome proliferator activated receptor ? coactivator (PGC)-1? has been suggested to be protective against low-grade inflammation. However, whether these anti-inflammatory properties affect acute inflammation is not known. The aim of the present study was therefore to investigate the role of muscle PGC-1? in acute inflammation. Quadriceps muscles were removed from 10-week old whole body PGC-1? knockout (KO), muscle specific PGC-1? KO (MKO) and muscle-specific PGC-1? overexpression mice (TG), 2 hours after an intraperitoneal injection of either 0.8 µg LPS/g body weight or saline. Basal TNF? mRNA content was lower in skeletal muscle of whole body PGC-1? KO mice and in accordance TG mice showed increased TNF? mRNA and protein level relative to WT, indicating a possible PGC-1? mediated regulation of TNF?. Basal p65 phosphorylation was increased in TG mice possibly explaining the elevated TNF? expression in these mice. Systemically, TG mice had reduced basal plasma TNF? levels compared with WT suggesting a protective effect against systemic low-grade inflammation in these animals. While TG mice reached similar TNF? levels as WT and showed more marked induction in plasma TNF? than WT after LPS injection, MKO PGC-1? mice had a reduced plasma TNF? and skeletal muscle TNF? mRNA response to LPS. In conclusion, the present findings suggest that PGC-1? enhances basal TNF? expression in skeletal muscle and indicate that PGC-1? does not exert anti-inflammatory effects during acute inflammation. Lack of skeletal muscle PGC-1? seems however to impair the acute TNF? response, which may reflect a phenotype more susceptible to infections as also observed in type 2 diabetes patients. PMID:22384185

  17. Long pentraxin PTX3 deficiency worsens LPS-induced acute lung injury

    Microsoft Academic Search

    Bing Han; Jack J. Haitsma; Yu Zhang; Xiaohui Bai; Matthew Rubacha; Shaf Keshavjee; Haibo Zhang; Mingyao Liu

    2011-01-01

    Objective  Long pentraxin PTX3 is an inflammatory mediator and a component of the humoral arm of innate immunity. PTX3 expression is\\u000a increased in animals with acute lung injury (ALI) and in patients with sepsis or acute respiratory distress syndrome and is\\u000a considered to be a potential biomarker for these diseases. However, the role of PTX3 in the pathogenesis of ALI is

  18. ROLE OF CELL SIGNALING IN PROTECTION FROM DIESEL AND LPS INDUCED ACUTE LUNG INJURY

    EPA Science Inventory

    We have previously demonstrated in CD-1 mice that pre-administration of N-acetyl cysteine (NAC) or the p38 MAP kinase inhibitor (SB203580) reduces acute lung injury and inflammation following pulmonary exposures to diesel exhaust particles (DEP) or lipopolysaccharide (LPS). Here ...

  19. Spirulina Promotes Stem Cell Genesis and Protects against LPS Induced Declines in Neural Stem Cell Proliferation

    Microsoft Academic Search

    Adam D. Bachstetter; Jennifer Jernberg; Andrea Schlunk; Jennifer L. Vila; Charles Hudson; Michael J. Cole; R. Douglas Shytle; Jun Tan; Paul R. Sanberg; Cyndy D. Sanberg; Cesario Borlongan; Yuji Kaneko; Naoki Tajiri; Carmelina Gemma; Paula C. Bickford; Tsuneya Ikezu

    2010-01-01

    Adult stem cells are present in many tissues including, skin, muscle, adipose, bone marrow, and in the brain. Neuroinflammation has been shown to be a potent negative regulator of stem cell and progenitor cell proliferation in the neurogenic regions of the brain. Recently we demonstrated that decreasing a key neuroinflammatory cytokine IL-1? in the hippocampus of aged rats reversed the

  20. AFFYMETRIX GENECHIP-BASED ANALYSIS OF THE GENOMIC RESPONSE TO ACUTE LPS-INDUCED BOVINE MASTITIS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genomic response of the bovine mammary gland was profiled four hours after an intramammary challenge with E. coli endotoxin (LPS). Three mid-lactation cows were challenged in one quarter with 1 ug of LPS while contralateral quarters received saline and served as within animal controls. RNA from ...

  1. Isoflavone-free soy protein diet inhibits LPS-induced inflammatory responses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recently, we showed reduced atherosclerotic lesions in a hyperlipidemic mouse model fed isoflavone-free soy protein diet (SPI–) compared to casein (CAS)-fed mice, despite unchanged serum lipid levels. However, the molecular mechanisms contributing to the atheroprotective effect of soy-based diets is...

  2. Regulation of LPS-induced tissue factor expression in human monocytic THP-1 cells by curcumin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tissue factor (TF) is a transmembrane receptor, which initiates thrombotic episodes associated with various diseases. In addition to membrane-bound TF, we have discovered an alternatively spliced form of human TF mRNA. It was later confirmed that this form of TF mRNA expresses a soluble protein circ...

  3. VIP Inhibits Porphyromonas gingivalis LPS-induced Immune Responses in Human Monocytes

    Microsoft Academic Search

    N. Foster; J. Cheetham; J. J. Taylor; P. M. Preshaw

    2005-01-01

    Lipopolysaccharide (LPS) from the Gramnegative pathogen Porphyromonas gingivalis (Pg) stimulates cytokine secretion in immune cells, and thereby initiates the inflammation associated with periodontitis. Modulation of pro-inflammatory cytokine activity is a plausible therapeutic target in periodontal disease. Vasoactive intestinal peptide (VIP) has a role in immunoregulation, and has been identified as a molecule with therapeutically beneficial immunosuppressive effects in inflammatory and

  4. The triterpenoid quinonemethide pristimerin inhibits induction of inducible nitric oxide synthase in murine macrophages

    Microsoft Academic Search

    Verena M Dirsch; Alexandra K Kiemer; Hildebert Wagner; Angelika M Vollmar

    1997-01-01

    Inducible nitric oxide synthase dependent production of nitric oxide (NO) plays an important role in inflammation. We investigated whether pristimerin ((20?)-3-hydroxy-2-oxo-24-nor-friedela-1(10),3,5,7-tetraen-carboxylic acid-(29)-methylester), an antitumoral, antimicrobial as well as anti-inflammatory plant compound, has an effect on the inducible NO synthase system in lipopolysaccharide-activated RAW 264.7 macrophages. Pristimerin dose dependently (IC50: 0.2–0.3 ?M) reduces nitrite accumulation, a parameter for NO synthesis, in

  5. Lipopolysaccharides of Brucella abortus and Brucella melitensis Induce Nitric Oxide Synthesis in Rat Peritoneal Macrophages

    Microsoft Academic Search

    LUIS LOPEZ-URRUTIA; ANDRES ALONSO; MARIA LUISA NIETO; YOLANDA BAYON; ANTONIO ORDUNA; MARIANO SANCHEZ CRESPO

    2000-01-01

    Received 28 October 1999\\/Returned for modification 16 November 1999\\/Accepted 6 December 1999 Smooth lipopolysaccharide (S-LPS) and lipid A of Brucella abortus and Brucella melitensis induced the production of nitric oxide (NO) by rat adherent peritoneal cells, but they induced lower levels of production of NO than Escherichia coli LPS. The participation of the inducible isoform of NO synthase (iNOS) was

  6. Isolation of benzoic and cinnamic acid derivatives from the grains of Sorghum bicolor and their inhibition of lipopolysaccharide-induced nitric oxide production in RAW 264.7 cells.

    PubMed

    Nguyen, Phi-Hung; Zhao, Bing Tian; Lee, Jeong Hyung; Kim, Young Ho; Min, Byung Sun; Woo, Mi Hee

    2015-02-01

    Two new caffeoylglycerols, (hwanggeumchal A-B, 9-10), together with eight known derivatives (1-8) were isolated from the grains of Sorghum bicolor (L.) Moench var. hwanggeumchal. Their chemical structures were established mainly by 1D and 2D NMR techniques and MS data analysis. Amongst those, methyl 3,4-dihydroxybenzoate (2), 3,4,5-trihydroxycinnamate (3), methyl 3,4-dihydroxycinnamate (5), caffeoylglycolic acid methyl ester (7) and 1-O-caffeoylglycerol (8) displayed potential inhibitory effects against LPS-induced NO production in macrophage RAW264.7 cells with IC50 values of 11.9, 2.9, 27.1, 29.0 and 18.5?M, respectively. Furthermore, these compounds dose-dependently reduced the LPS-induced iNOS expression. In addition, pre-incubation of cells with compounds 2, 3 and 5 significantly suppressed LPS-induced COX-2 protein expression. SAR investigation revealed that compounds with a methyl ester (COOCH3) group possessed stronger activity. Our obtained data suggest that S. bicolor and its caffeoylglyceride-enrich extracts may be applied as supplemental and/or functional foods having a beneficial effect against inflammation. PMID:25172742

  7. Behavioral impairments and changes of nitric oxide and inducible nitric oxide synthase in the brains of molarless KM mice.

    PubMed

    Pang, Qian; Hu, Xingxue; Li, Xinya; Zhang, Jianjun; Jiang, Qingsong

    2015-02-01

    More studies showed that as a common disorder in senior population, loss of teeth could adversely affect human cognitive function, and nitric oxide (NO) might play an important role in the cognitive function. However, the underlying mechanism has not yet been well-established. The objectives of this study are to evaluate behavior changes of KM mice after loss of molars, and levels of NO and inducible nitric oxide synthase (iNOS) in the brain in molarless condition. It is hypothesized that loss of molars of the mice tested results in the cognitive impairments and that the process is mediated by NO in the brain through the signaling pathways. Morris water maze is used to test the behavioral changes after 8 weeks of the surgery. The changes of NO and iNOS are evaluated by using Griess assay, western blot, and immunohistochemistry method. The results show that 8 weeks after loss of molars, the spatial learning and memory of KM mice impair and the levels of NO and iNOS in mice hippocampus increase. These findings suggest that molar extraction is associated with the behavioral impairment, and that the changes of NO and iNOS in the hippocampus may be involved in the behavioral changes in the molarless condition. PMID:25447296

  8. Pro-VGF-derived peptides induce penile erection in male rats: Involvement of paraventricular nitric oxide.

    PubMed

    Succu, Salvatora; Mascia, Maria Stefania; Melis, Tiziana; Sanna, Fabrizio; Melis, Maria Rosaria; Possenti, Roberta; Argiolas, Antonio

    2005-12-01

    The effect of four peptides derived from the C-terminal portion of rat pro-VGF(556-617) (VGF(556-576), VGF(588-617), VGF(599-617), and VGF(588-597)), on penile erection and nitric oxide production in the paraventricular nucleus of the hypothalamus was studied in male rats after injecting into this hypothalamic nucleus. VGF(588-617) (0.5, 1 and 2 microg), VGF(599-617) (0.5, 2 and 5 microg) and, to a lower extent, VGF(588-597) (2 and 5 microg) induced penile erection episodes when injected into the paraventricular nucleus and concomitantly increased paraventricular nitric oxide production, while VGF(556-576) (5 microg) was ineffective. VGF(588-617)-induced nitric oxide production was reduced by N(G)-nitro-l-arginine methylester (l-NAME) (20 microg), a nitric oxide synthase inhibitor, which also reduced penile erection when injected in the paraventricular nucleus 15 min before the VGF peptide. The oxytocin receptor antagonist d(CH(2))(5)Tyr(Me)-Orn(8)-vasotocin (1 microg) also effectively reduced VGF(588-617)-induced penile erection when given into the lateral ventricles, but not when injected into the paraventricular nucleus. In both experimental conditions, d(CH(2))(5)Tyr(Me)-Orn(8)-vasotocin was unable to influence nitric oxide production in the paraventricular nucleus. The present results confirm that C-terminal pro-VGF-derived peptides induce penile erection when injected into the paraventricular nucleus and show that this effect is mediated by an increased nitric oxide production in this hypothalamic nucleus. Apparently, this causes the activation of paraventricular oxytocinergic neurons projecting to extra-hypothalamic brain areas and mediating penile erection, as found with dopamine agonists, oxytocin, excitatory amino acids and hexarelin analogue peptides. PMID:16087201

  9. Endogenous nitric oxide inhibits endothelin-1-induced chloride secretion in guinea pig colon.

    PubMed

    Reddix, R A; Mullet, D; Fertel, R; Cooke, H J

    1998-01-01

    Segments of guinea pig distal colon, stripped of the external muscle layers, were set up in flux chambers for measurement of short-circuit current (Isc) indicative of active, electrogenic ion transport. During neural blockade with tetrodotoxin, the nitric oxide scavenger, hemoglobin, and the nitric oxide synthase inhibitor, N omega-nitro-L-arginine (L-NNA), reduced Isc. The reduction in Isc in response to hemoglobin was reversed by L-arginine and blockers of chloride secretion, including bumetanide and diphenylamine-2-carboxylic acid, but not by the potassium channel blockers, barium and tetraethylammonium, nor by amiloride, an epithelial sodium channel blocker. The hemoglobin-induced reduction in Isc was not affected by blockade of prostaglandin synthesis with piroxicam. During neural blockade, the nitric oxide donors, sodium nitroprusside and NONOate, increased Isc which was abolished by piroxicam. Endothelin-1 (ET-1) also evoked an increase in Isc that was unaffected by amiloride and was inhibitable by bumetanide, chloride-free solutions, tetrodotoxin, piroxicam, and the ETA receptor antagonist, BQ123. The ETB receptor agonist, [Ala1,3,11,15]-endothelin-1, had no appreciable effect on Isc. Hemoglobin and L-NNA enhanced the ET-1-induced Isc response by about twofold without affecting prostaglandin E2 release or its secretory response. The results suggest that endogenous nitric oxide stimulates a low level of chloride secretion that is independent of prostaglandins, unlike nitric oxide donors which increase chloride secretion by releasing prostaglandins. In addition, endogenous nitric oxide suppresses ET-1-evoked chloride secretion by mechanisms that are unrelated to the release of prostaglandin E2 or its ability to stimulate epithelial cells. Endogenous nitric oxide may play an important role in modulating chloride secretion during ischemic challenge when endothelin levels are high. PMID:9706740

  10. New ambuic acid derivatives from the solid culture of Pestalotiopsis neglecta and their nitric oxide inhibitory activity

    PubMed Central

    Qi, Qiu-Yue; Li, Er-Wei; Han, Jun-Jie; Pei, Yun-Fei; Ma, Ke; Bao, Li; Huang, Ying; Zhao, Feng; Liu, Hong-Wei

    2015-01-01

    Four new ambuic acid derivatives (1–4), and four known derivatives (5–8), were isolated from the solid culture of a plant pathogenic fungus Pestalotiopsis neglecta. Their structures were elucidated by extensive NMR experiments. The absolute configuration of the C-16 secondary alcohol in 1 was deduced via the CD data of the in situ formed [Rh2(OCOCF3)4] complex with the acetonide derivative of 1. The absolute configuration in 3 was assigned by comparison of the experimental and simulated electronic circular dichroism (ECD) spectrum. The NMR data of compound 5 was reported for the first time. In the nitric oxide (NO) inhibition assay, compounds 4, 6 and 7 showed inhibitory activity against the NO production in the lipopolysaccharide (LPS)-induced macrophage with IC50 values of 88.66, 11.20, and 20.80?µM, respectively. PMID:25989228

  11. Five withanolides from the leaves of Datura metel L. and their inhibitory effects on nitric oxide production.

    PubMed

    Yang, Bing-You; Guo, Rui; Li, Ting; Liu, Yan; Wang, Chang-Fu; Shu, Zun-Peng; Wang, Zhi-Bin; Zhang, Jing; Xia, Yong-Gang; Jiang, Hai; Wang, Qiu-Hong; Kuang, Hai-Xue

    2014-01-01

    Four new withanolides named dmetelins A-D (compounds 1-4), along with the known compound 7?,27-dihydroxy-1-oxo-witha-2,5,24-trienolide (5) were isolated from the leaves of Datura metel L. (Solanaceae). Their structures were elucidated on the basis of detailed analysis of 1D and 2D NMR and mass spectrometry data. All the compounds were evaluated for their inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 cells. Compounds 1, 4 and 5 showed significant inhibitory activities, and compounds 2 and 3 showed moderate inhibitory activities with IC50 values of 17.8, 11.6, 14.9, 33.3 and 28.6 ?M, respectively. PMID:24731984

  12. Microangiopathy triggers, and inducible nitric oxide synthase exacerbates dextran sulfate sodium-induced colitis.

    PubMed

    Saijo, Hiroki; Tatsumi, Norifumi; Arihiro, Seiji; Kato, Tomohiro; Okabe, Masataka; Tajiri, Hisao; Hashimoto, Hisashi

    2015-07-01

    Ulcerative colitis (UC) is a representative clinical manifestation of inflammatory bowel disease that causes chronic gastrointestinal tract inflammation. Dextran sulfate sodium (DSS)-induced colitis mice have been used to investigate UC pathogenesis, and in this UC model, disturbance and impairment of the mucosal epithelium have been reported to cause colitis. However, how DSS sporadically breaks down the epithelium remains unclear. In this study, we focused on the colonic microcirculation and myenteric neurons of DSS-induced colitis. Moreover, we examined the potential of myenteric neurons as a target to prevent exacerbation of colitis. Fluorescent angiographic and histopathological studies revealed that DSS administration elicited blood vessel disruption before epithelial disorders appeared. Ischemic conditions in the lamina propria induced inducible nitric oxide synthase (iNOS) expression in myenteric neurons as colitis aggravated. When neuronal activity was inhibited with butylscopolamine, neuronal iNOS expression decreased, and the exacerbation of colitis was prevented. These results suggested that DSS-induced colitis was triggered by microcirculatory disturbance in the mucosa, and that excessive neuronal excitation aggravated colitis. During remission periods of human UC, endoscopic inspection of the colonic microcirculation may enable the early detection of disease recurrence, and inhibition of neuronal iNOS expression may prevent the disease from worsening. PMID:25938626

  13. Nitric Oxide Induces Cell Death by Regulating Anti-Apoptotic BCL2 Family Members

    Microsoft Academic Search

    Colleen M. Snyder; Emelyn H. Shroff; Jing Liu; Navdeep S. Chandel; Syed A. Aziz

    2009-01-01

    Nitric oxide (NO) activates the intrinsic apoptotic pathway to induce cell death. However, the mechanism by which this pathway is activated in cells exposed to NO is not known. Here we report that BAX and BAK are activated by NO and that cytochrome c is released from the mitochondria. Cells deficient in Bax and Bak or Caspase-9 are completely protected

  14. Comparative localization of endothelial and inducible nitric oxide synthase isoforms in haemochorial and epitheliochorial placentae

    Microsoft Academic Search

    T. J. Zarlingo; A. L. W. Eis; D. E. Brockman; W. Kossenjans; L. Myatt

    1997-01-01

    The presence and immunolocalization of type II (inducible or macrophage) and type III (endothelial) nitric oxide synthase (NOS) isoforms were compared in the term placentae of humans, rhesus monkeys, baboons, guinea-pigs, rats and sheep using isoform specific antibodies. In the human placenta, intense immunohistochemical staining for type III NOS was seen in syncytiotrophoblast with weaker staining in vascular endothelial cells.

  15. Effect of allicin and ajoene, two compounds of garlic, on inducible nitric oxide synthase

    Microsoft Academic Search

    Verena M Dirsch; Alexandra K Kiemer; Hildebert Wagner; Angelika M Vollmar

    1998-01-01

    Inducible nitric oxide synthase (iNOS) has recently been shown to be present in human atherosclerotic lesions and to promote the formation of deleterious peroxynitrite. Allicin and ajoene are discussed as active compounds with regard to the beneficial effects of garlic in atherosclerosis. The aim of this study was to investigate the effect of allicin and ajoene on the iNOS system

  16. Hypoxia-induced nitric oxide protects chondrocytes from damage by hydrogen peroxide

    Microsoft Academic Search

    T. Matsushita; K. Fukuda; K. Yamazaki; N. Yamamoto; S. Asada; K. Yoshida; H. Munakata; C. Hamanishi

    2004-01-01

    Objective:Because articular cartilage has no vascular supply, chondrocytes are hypoxic under normal physiological conditions. Nitric oxide (NO) plays an important role in chondrocyte damage, such as apoptosis. Although oxygen stress with hydrogen peroxide was found to cause chondrocyte damage, these data were obtained under normoxic (21% O 2) conditions. We investigated the effects of hypoxia on hydrogen peroxide-induced chondrocyte damage

  17. Aldose reductase mediates endotoxin-induced production of nitric oxide and cytotoxicity in murine macrophages

    Microsoft Academic Search

    Kota V. Ramana; Aramati B. M. Reddy; Ravinder Tammali; Satish K. Srivastava

    2007-01-01

    Aldose reductase (AR) is a ubiquitously expressed protein with pleiotrophic roles as an efficient catalyst for the reduction of toxic lipid aldehydes and mediator of hyperglycemia, cytokine, and growth factor-induced redox-sensitive signals that cause secondary diabetic complications. Although AR inhibition has been shown to be protective against oxidative stress signals, the role of AR in regulating nitric oxide (NO) synthesis

  18. TRPV1 and TRPA1 Mediate Peripheral Nitric Oxide-Induced Nociception in Mice

    Microsoft Academic Search

    Takashi Miyamoto; Adrienne E. Dubin; Matt J. Petrus; Ardem Patapoutian; Louis S. Premkumar

    2009-01-01

    Nitric oxide (NO) can induce acute pain in humans and plays an important role in pain sensitization caused by inflammation and injury in animal models. There is evidence that NO acts both in the central nervous system via a cyclic GMP pathway and in the periphery on sensory neurons through unknown mechanisms. It has recently been suggested that TRPV1 and

  19. Platelet-activating factor augments lipopolysaccharide-induced nitric oxide formation by rat Kupffer cells

    Microsoft Academic Search

    SB Mustafa; KM Howard

    1996-01-01

    Acute endotoxic shock is accompanied by an increase in the production of nitric oxide (NO) by several different hepatic cell types. Platelet-activating factor (PAF) is a potent proinflammatory mediator with many pathophysiological actions and, in fact, elevated plasma and tissue levels of PAF are observed in animal models of endotoxic shock. The current study demonstrates that PAF induced nitrite formation,

  20. Nitric Oxide Induces the Synthesis of Vascular Endothelial Growth Factor by Rat Vascular Smooth Muscle Cells

    Microsoft Academic Search

    Jozef Dulak; Alicja Jozkowicz; Aldona Dembinska-Kiec; Ibeth Guevara; Anna Zdzienicka; Danuta Zmudzinska-Grochot; Izabela Florek; Anna Wojtowicz; Andrzej Szuba; John P. Cooke

    2010-01-01

    Vascular endothelial growth factor (VEGF) is known to induce the release of nitric oxide (NO) from endothelial cells. However, the effect of NO on VEGF synthesis is not clear. Accordingly, the effect of endogenous and exogenous NO on VEGF synthesis by rat vascular smooth muscle cells (VSMCs) was investigated. Two in vitro models were used: (1) VSMCs stimulated to produce

  1. Endrin-induced production of nitric oxide by rat peritoneal macrophages.

    PubMed

    Akubue, P I; Stohs, S J

    1992-09-01

    The effect of oral endrin administration to rats on the production of nitric oxide (NO) by peritoneal macrophages was investigated. Nitric oxide formation was measured as nitrite. Endrin (4.5 mg/kg) enhanced the secretion of NO by approx. 300%. The effect of endrin on NO formation was both dose- and time-dependent. Ellagic acid, which has been shown to be a potent antioxidant, inhibited the elevation of NO production induced by endrin. These results suggest that the toxicity of endrin may at least in part be due to the production of an oxidative stress. PMID:1412516

  2. Protective role of nitric oxide during hydrogen peroxide-induced oxidative stress in tobacco plants

    Microsoft Academic Search

    L. V. Dubovskaya; E. V. Kolesneva; D. M. Knyazev; I. D. Volotovskii

    2007-01-01

    Nitric oxide, produced from exogenous NO donor, sodium nitroprusside, and hydrogen peroxide exerted antagonistic effects on\\u000a tobacco leaves at micromolar concentrations but induced synergistic effects at millimolar concentrations. During H2O2-induced oxidative stress, low concentrations of NO inhibited lipid peroxidation, counteracted the fragmentation of total\\u000a DNA, and prevented accumulation of soluble proteins in Nicotiana plumbaginifolia cells. When applied at high concentrations,

  3. Expression of inducible nitric oxide synthase and nitrotyrosine in colonic epithelium in inflammatory bowel disease

    Microsoft Academic Search

    II Singer; DW Kawka; S Scott; JR Weidner; RA Mumford; TE Riehl; WF Stenson

    1996-01-01

    BACKGROUND & AIMS: Inducible nitric oxide synthase (iNOS) is generated in several cell types by treatment with lipopolysaccharides or cytokines. Earlier studies suggested that ulcerative colitis is associated with increased NO produced by iNOS; however, the cellular source of the NO synthesis was not identified. A possible mechanism of NO-induced cellular damage is through its interaction with superoxide to produce

  4. Calmodulin-induced structural changes in endothelial nitric oxide synthase

    PubMed Central

    Persechini, Anthony; Tran, Quang-Kim; Black, D.J.; Gogol, Edward P.

    2013-01-01

    We have derived structures of intact calmodulin(CaM)-free and CaM-bound endothelial nitric oxide synthase (eNOS) by reconstruction from cryo-electron micrographs. The CaM-free reconstruction is well fitted by the oxygenase domain dimer, but the reductase domains are not visible, suggesting they are mobile and thus delocalized. Additional protein is visible in the CaM-bound reconstruction, concentrated in volumes near two basic patches on each oxygenase domain. One of these corresponds with a presumptive docking site for the reductase domain FMN-binding module. The other is proposed to correspond with a docking site for CaM. A model is suggested in which CaM binding and docking position the reductase domains near the oxygenase domains and promote docking of the FMN-binding modules required for electron transfer. PMID:23266515

  5. Inhibitory effects of N-(substituted benzoylamino)-4-ethyl-1,2,3,6-tetrahydropyridines on nitric oxide generation in stimulated raw 264.7 macrophages.

    PubMed

    Yoon, K; Soliman, K; Redda, K

    2002-01-01

    There has been great interest in reactive nitrogen intermediates and nitric oxide production in macrophages, particularly because of their contributory role in several pathophysiological conditions during acute and chronic inflammation. Several N-(substituted benzoylamino)-4-ethyl-1,2,3,6-tetrahydropyridines were previously synthesized as potential antiinflammatory agents. In the present study, the effects of four previously synthesized tetrahydropyridines (THPs) on cyclooxygenase (COX)-1 and COX-2 were screened and the effects of these compounds on lipopolysaccharide (LPS)-induced (2 micrograms/ml) nitric oxide and inducible nitric oxide synthase (iNOS) activity in RAW 264.7 macrophages were examined. 4-Bromo THP showed 9.4 microM of IC50 as the most potent derivative among the tested THPs followed by 4-nbuthyl, 4-fuoro, and 4-methyl THP with IC50 values of 30.9, 38.9 and 80.3 microM, respectively (indomethacin IC50 = 53.8 microM). None of the tested compounds showed cytotoxic effects to the RAW 264.7 macrophages. All of the tested THPs exhibited COX-1 and COX-2 nonselective inhibition. These results suggest that previously synthesized THP derivatives may have dual effects through inhibiting both COX and nitric oxide by inhibiting iNOS. PMID:12224381

  6. Aminoguanidine, an inhibitor of inducible nitric oxide synthase, ameliorates experimental autoimmune encephalomyelitis in SJL mice.

    PubMed Central

    Cross, A H; Misko, T P; Lin, R F; Hickey, W F; Trotter, J L; Tilton, R G

    1994-01-01

    Previous work from our laboratory localized nitric oxide to the affected spinal cords of mice with experimental autoimmune encephalomyelitis, a prime model for the human disease multiple sclerosis. The present study shows that activated lymphocytes sensitized to the central nervous system encephalitogen, myelin basic protein, can induce nitric oxide production by a murine macrophage cell line. Induction was inhibited by amino-guanidine, a preferential inhibitor of the inducible nitric oxide synthase isoform, and by NG-monomethyl-L-arginine. Aminoguanidine, when administered to mice sensitized to develop experimental autoimmune encephalomyelitis, inhibited disease expression in a dose-related manner. At 400 mg aminoguanidine/kg per day, disease onset was delayed and the mean maximum clinical score was 0.9 +/- 1.2 in aminoguanidine versus 3.9 +/- 0.9 in placebo-treated mice. Histologic scoring of the spinal cords for inflammation, demyelination, and axonal necrosis revealed significantly less pathology in the aminoguanidine-treated group. The present study implicates excessive nitric oxide production in the pathogenesis of murine inflammatory central nervous system demyelination, and perhaps in the human disease multiple sclerosis. Images PMID:7515395

  7. Cyanidin-3-O-beta-glucoside inhibits iNOS and COX-2 expression by inducing liver X receptor alpha activation in THP-1 macrophages.

    PubMed

    Wang, Qing; Xia, Min; Liu, Chi; Guo, Honghui; Ye, Qingyuan; Hu, Yan; Zhang, Yinghui; Hou, Mengjun; Zhu, Huilian; Ma, Jing; Ling, Wenhua

    2008-08-01

    Anthocyanins belong to a large and widespread group of water-soluble phytochemicals and exhibit potent antioxidative and anti-inflammatory properties; however, the molecular mechanisms of these biochemical actions mediated by anthocyanins remain unclear. In this study, our data show that pretreatment of THP-1 macrophages with Cyanidin-3-O-beta-glucoside (C3G) for 12 h can enhance the expression and transcriptional activities of the nuclear receptor peroxisome proliferator-activated receptor gamma (PPARgamma) and liver X receptor alpha (LXRalpha). Furthermore, pretreatment of these cells with C3G for 12 h causes dose-dependent inhibition of lipopolysaccharide (LPS)-induced nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at both the mRNA and protein levels together with a decrease in nitric oxide (NO) and prostaglandin E(2) (PGE(2)) production. Consequently, addition of geranylgeranyl pyrophosphate ammonium salt (GGPP), an LXRalpha antagonist, significantly downregulates the inhibitory effect of C3G on LPS-induced iNOS and COX-2 expression in THP-1 macrophages, whereas the PPARgamma antagonist GW9662 has no effect. Further investigation revealed that LXRalpha might interfere with LPS-induced iNOS and COX-2 expression by suppressing the functional activation of nuclear factor-kappaB (NF-kappaB), not - as was previously proposed - by reducing NF-kappaB nuclear translocation. Taken together, these results indicate that LXRalpha activation has an essential role in the anti-inflammatory property of C3G. Moreover, they provide new insight into the molecular basis for the anti-inflammatory property of anthocyanins. PMID:18619979

  8. Traumatic Brain Injury Disrupts Cerebrovascular Tone Through Endothelial Inducible Nitric Oxide Synthase Expression and Nitric Oxide Gain of Function

    PubMed Central

    Villalba, Nuria; Sonkusare, Swapnil K.; Longden, Thomas A.; Tran, Tram L.; Sackheim, Adrian M.; Nelson, Mark T.; Wellman, George C.; Freeman, Kalev

    2014-01-01

    Background Traumatic brain injury (TBI) has been reported to increase the concentration of nitric oxide (NO) in the brain and can lead to loss of cerebrovascular tone; however, the sources, amounts, and consequences of excess NO on the cerebral vasculature are unknown. Our objective was to elucidate the mechanism of decreased cerebral artery tone after TBI. Methods and Results Cerebral arteries were isolated from rats 24 hours after moderate fluid?percussion TBI. Pressure?induced increases in vasoconstriction (myogenic tone) and smooth muscle Ca2+ were severely blunted in cerebral arteries after TBI. However, myogenic tone and smooth muscle Ca2+ were restored by inhibition of NO synthesis or endothelium removal, suggesting that TBI increased endothelial NO levels. Live native cell NO, indexed by 4,5?diaminofluorescein (DAF?2 DA) fluorescence, was increased in endothelium and smooth muscle of cerebral arteries after TBI. Clamped concentrations of 20 to 30 nmol/L NO were required to simulate the loss of myogenic tone and increased (DAF?2T) fluorescence observed following TBI. In comparison, basal NO in control arteries was estimated as 0.4 nmol/L. Consistent with TBI causing enhanced NO?mediated vasodilation, inhibitors of guanylyl cyclase, protein kinase G, and large?conductance Ca2+?activated potassium (BK) channel restored function of arteries from animals with TBI. Expression of the inducible isoform of NO synthase was upregulated in cerebral arteries isolated from animals with TBI, and the inducible isoform of NO synthase inhibitor 1400W restored myogenic responses following TBI. Conclusions The mechanism of profound cerebral artery vasodilation after TBI is a gain of function in vascular NO production by 60?fold over controls, resulting from upregulation of the inducible isoform of NO synthase in the endothelium. PMID:25527626

  9. Prevention of neural tube defects by loss of function of inducible nitric oxide synthase in fetuses of a mouse model of streptozotocin-induced diabetes

    Microsoft Academic Search

    Y. Sugimura; T. Murase; K. Oyama; A. Uchida; N. Sato; S. Hayasaka; Y. Kano; Y. Takagishi; Y. Hayashi; Y. Oiso; Y. Murata

    2009-01-01

    Aims\\/hypothesis  Maternal diabetes during pregnancy increases the risk of congenital malformations such as neural tube defects (NTDs). Although\\u000a the mechanism of this effect is uncertain, it is known that levels of nitric oxide synthase (NOS) and nitric oxide are elevated\\u000a in embryos of a mouse model of diabetes. We postulated that overproduction of nitric oxide causes diabetes-induced congenital\\u000a malformations and that

  10. Nitric oxide mediates, and acetylcholine modulates, neurally induced relaxation of bovine cerebral arteries.

    PubMed

    Ayajiki, K; Okamura, T; Toda, N

    1993-06-01

    Helical strips of bovine basilar arteries denuded of the endothelium responded to transmural electrical stimulation with frequency-dependent relaxations that were abolished or markedly attenuated by treatment with tetrodotoxin, oxyhemoglobin and Methylene Blue. Relaxations induced by vasoactive intestinal polypeptide and calcitonin gene-related peptide were not affected by oxyhemoglobin and Methylene Blue. The neurally induced relaxation was not attenuated in the artery made unresponsive to these peptides by successive application. The relaxation caused by nerve stimulation was markedly inhibited by treatment with NG-nitro-L-arginine, a nitric oxide synthase inhibitor, which did not inhibit the relaxation caused by exogenously applied nitric oxide. The inhibition was reversed by L-arginine but not by the D-enantiomer. Exogenously applied acetylcholine did not alter the tone of endothelium-denuded arteries. Neurally induced relaxations were attenuated by treatment with acetylcholine and physostigmine and were significantly potentiated by atropine. It may be concluded that the relaxation induced by nerve stimulation is mediated by nitric oxide, but not by vasoactive intestinal polypeptide or calcitonin gene-related peptide, derived from vasodilator nerves innervating the bovine basilar artery, and the nerve function is inhibited prejunctionally via muscarinic receptor activation by acetylcholine released from cholinergic nerves but is not influenced by vasoactive intestinal polypeptide. PMID:8332264

  11. The role of nitric oxide in testosterone-induced vasodilation in pig coronary arteries and rat thoracic aorta 

    E-print Network

    Piefer, Jason William

    2013-02-22

    Several studies have provided evidence that the administration of testosterone to vascular tissue causes vasodilation (Costarella, Yue). This study examines the role of nitric oxide (NO) as a potential mechanism of testosterone-induced vasodilation...

  12. Lipopolysaccharides of Brucella abortus and Brucella melitensis Induce Nitric Oxide Synthesis in Rat Peritoneal Macrophages

    PubMed Central

    López-Urrutia, Luis; Alonso, Andrés; Nieto, Maria Luisa; Bayón, Yolanda; Orduña, Antonio; Sánchez Crespo, Mariano

    2000-01-01

    Smooth lipopolysaccharide (S-LPS) and lipid A of Brucella abortus and Brucella melitensis induced the production of nitric oxide (NO) by rat adherent peritoneal cells, but they induced lower levels of production of NO than Escherichia coli LPS. The participation of the inducible isoform of NO synthase (iNOS) was confirmed by the finding of an increased expression of both iNOS mRNA and iNOS protein. These observations might help to explain (i) the acute outcome of Brucella infection in rodents, (ii) the low frequency of septic shock in human brucellosis, and (iii) the prolonged intracellular survival of Brucella in humans. PMID:10679001

  13. Role of nitric oxide on pathogenesis of 5-fluorouracil induced experimental oral mucositis in hamster

    Microsoft Academic Search

    R. F. C. Leitão; R. A. Ribeiro; E. A. L. Bellaguarda; F. D. B. Macedo; L. R. Silva; R. B. Oriá; M. L. Vale; F. Q. Cunha; G. A. C. Brito

    2007-01-01

    Introduction  Mucositis induced by antineoplastic drugs is an important, dose-limiting, and costly side effect of cancer therapy. Aim: To investigate the role of nitric oxide (NO) on the pathogenesis of 5-fluorouracil (5-FU)-induced oral mucositis.\\u000a \\u000a \\u000a \\u000a Materials and Methods  Oral mucositis was induced by two intraperitoneal (i.p) administrations of 5-FU on the first and second days of the experiment\\u000a (60 and 40 mg\\/kg, respectively) in

  14. Horseradish peroxidase and glycosylated BSA induce nitric oxide production in murine macrophages.

    PubMed

    Afroun-Talantikite, S; Ouazzani, J

    1996-06-01

    The in vitro activation of murine macrophages by horseradish peroxidase (HRP) induced nitric oxide production in a dose-dependent manner, and increased the induction of NO-synthase by LPS. Nitrite production after HRP stimulation was inhibited by NG-monomethyl-L-arginine (NMMA), a specific inhibitor of NO-synthase. Equivalent amounts of nitrite were obtained with native and heat-inactivated HRP. High concentrations of mannose inhibited nitric oxide production, while the HRP inhibitor 3-aminotyrosine did not. Glycosylated serum albumin derivatives also induced murine macrophage NOS, probably by an interaction between carbohydrates and their specific cell membrane receptors. The inability of HRP apoprotein to stimulate NO production, and the specific inhibition of HRP-mediated activation of macrophages by hemin suggests that the heme moiety of this enzyme is involved in NO-synthase induction. PMID:8881279

  15. Extract of Meretrix meretrix Linnaeus induces angiogenesis in vitro and activates endothelial nitric oxide synthase

    NASA Astrophysics Data System (ADS)

    Liu, Ming; Wei, Jianteng; Wang, Hui; Ding, Lili; Zhang, Yuyan; Lin, Xiukun

    2012-09-01

    Meretrix meretrix Linnaeus has long been used as traditional Chinese medicine in oriental medicine. The angiogentic activity of the extract of M. meretrix was investigated in this study, using human umbilical vein endothelial cells (HUVECs). Extract of M. meretrix Linnaeus (AFG-25) was prepared with acetone and ethanol precipitation, and further separated by Sephadex G-25 column. The results show that AFG-25 promoted proliferation, migration, and capillary-like tube formation in HUVECs, and in the presence of eNOS inhibitor NMA, the tube formation induced by AFG-25 is inhibited significantly. Moreover, AFG-25 could also promote the activation of endothelial nitric oxide synthase (eNOS) and the resultant elevation of nitric oxide (NO) production. The results suggested that M. meretrix contains active ingredients with angiogentic activity and eNOS/NO signal pathway is in part involved in the proangiogenesis effect induced by AFG-25.

  16. Screening of Indonesian medicinal plants for inhibitor activity on nitric oxide production of RAW264.7 cells and antioxidant activity.

    PubMed

    Choi, Eun-Mi; Hwang, Jae-Kwan

    2005-03-01

    Traditional Indonesian medicinal plants were screened for their inhibitory effects on the nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages and for the antioxidant activity through the evaluation of free radical scavenging effect and reducing power. The results of screening indicated that 50 methanolic extracts inhibited (>50%) lipopolysaccharides (LPS)-induced NO release from RAW264.7 cells at 50 microg/ml, with 18 having greater than 100% inhibition. At 200 microg/ml, 61 methanol extracts exhibited inhibitory activity (>50%), with 45 showing greater than 100% inhibition. In addition, the free radical scavenging effects of 6 methanolic extracts were found to be more than 50% for extract concentration of 0.5 mug/ml. The results indicate that the extracts contain active compounds that inhibit NO release and scavenge free radical. PMID:15752630

  17. Cytokine-induced nitric oxide production inhibits mitochondrial energy production and impairs contractile function in rat cardiac myocytes

    Microsoft Academic Search

    Tetsuya Tatsumi; Satoaki Matoba; Akira Kawahara; Natsuya Keira; Jun Shiraishi; Kazuko Akashi; Miyuki Kobara; Tetsuya Tanaka; Maki Katamura; Chiaki Nakagawa; Bon Ohta; Takeshi Shirayama; Kazuo Takeda; Jun Asayama; Henry Fliss; Masao Nakagawa

    2000-01-01

    OBJECTIVESThe present study examined whether nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) can directly inhibit aerobic energy metabolism and impair cell function in interleukin (IL)-1?–stimulated cardiac myocytes.BACKGROUNDRecent reports have indicated that excessive production of NO induced by cytokines can disrupt cellular energy balance through the inhibition of mitochondrial respiration in a variety of cells. However, it is

  18. Significance of inducible nitric oxide synthase in acute myocarditis caused by Trypanosoma cruzi (Tulahuen strain)

    Microsoft Academic Search

    Madhulika Chandra; Herbert B. Tanowitz; Stefka B. Petkova; Huan Huang; Louis M. Weiss; Murray Wittner; Stephen M. Factor; Vitaliy Shtutin; Linda A. Jelicks; John Chan; Jamshid Shirani

    2002-01-01

    Chagas’ disease, caused by Trypanosoma cruzi, is associated with myocarditis and expression of myocardial cytokines and inducible nitric oxide synthase (NOS2). To assess the functional significance of NOS2 in murine Chagas’ disease, we infected NOS2 knockout (NOS2?\\/?) and C57BL\\/6×129sv (wild type) mice with the Tulahuen strain of T. cruzi. Serial transthoracic echocardiography was performed to assess the progression of left

  19. Altered responses to bacterial infection and endotoxic shock in mice lacking inducible nitric oxide synthase

    Microsoft Academic Search

    John D. MacMicking; Carl Nathan; Gary Hom; Nicole Chartrain; Daniel S. Fletcher; Myrna Trumbauer; Karla Stevens; Qiao-wen Xie; Karen Sokol; Nancy Hutchinson; Howard Chen; John S. Mudget

    1995-01-01

    Mice deficient in inducible nitric oxide synthase (iNOS) were generated to test the idea that !NOS defends the host against infectious agents and tumor cells at the risk of contributing to tissue damage and shock. iNOS-I- mice failed to restrain the replication of Listeria monocytogenes in vivo or lymphoma cells in vitro. Bacterial endotoxic lipopolysaccharide (LPS) caused shock and death

  20. Inflammation-induced endothelial dysfunction involves reduced nitric oxide bioavailability and increased oxidant stress

    Microsoft Academic Search

    Brian R. Clapp; Aroon D. Hingorani; Rajesh K. Kharbanda; Vidya Mohamed-Ali; Jeffrey W. Stephens; Patrick Vallance; Raymond J. MacAllister

    2004-01-01

    Objectives: Our aim was to investigate mechanisms of inflammation-induced endothelial dysfunction in humans. Methods: Endothelial function in twenty-one healthy human volunteers was measured using forearm venous plethysmography before and 8 h after administration of typhoid vaccination to generate an inflammatory response. Basal and stimulated endothelial nitric oxide (NO) bioavailability was assessed by measurement of the responses to intra-arterial NG-monomethyl-l-arginine (l-NMMA)

  1. Failure of L-Nitroarginine to Inhibit the Activity of Aortic Inducible Nitric Oxide Synthase

    Microsoft Academic Search

    Benoit Darblade; Sandor Batkai; Elisabeth Caussé; Pierre Gourdy; Marie-José Fouque; Jacques Rami; Jean-François Arnal

    2001-01-01

    Nitric oxide (NO) is produced by a family of three isoenzymes: the endothelial, inducible and neuronal NO synthases. L-Nitroarginine methyl ester (L-NAME) is the most commonly used inhibitor of NO synthase activity. The goal of the present study was to evaluate to what extent L-nitroarginine (L-NA), the in vivo circulating metabolite of L-NAME, blocks NO production in the rat aorta

  2. Nitric oxide modulates pancreatic edema formation in rat caerulein-induced pancreatitis

    Microsoft Academic Search

    Takashi Abe; Tooru Shimosegawa; Akihiko Satoh; Reishi Abe; Yoshifumi Kikuchi; Masaru Koizumi; Takayoshi Toyota

    1995-01-01

    This study was designed to investigate the role of nitric oxide (NO) in the formation of pancreatic edema in caerulein-induced\\u000a pancreatitis in rats. Pancreatitis was produced by two intraperitoneal injections of caerulein, and plasma amylase concentration,\\u000a pancreatic edema index (pancreatic wet weight\\/body weight), and Evans blue extravasation (as a measure of vascular permeability)\\u000a were evaluated 5h after the first injection.

  3. Inhibition of Inducible Nitric Oxide Synthase Alters Thy1 Glomeruonephritis in Rats

    Microsoft Academic Search

    Joseph Satriano; Mark J. Lortie; Shunji Ishizuka; José M. Valdivielso; Beth Friedman; Karen A. Munger

    2006-01-01

    Background\\/Aims: Inducible nitric oxide (NO) synthase (iNOS) generated NO increases in the early phase of Thy-1 glomerulonephritis concurrently with mesangiolysis and reduction in glomerular filtration rate (GFR). Activation of ornithine decarboxylase (ODC), the rate-limiting enzyme of polyamine biosynthesis, is upregulated to allow mesangial cell proliferation which constitutes the repair phase in this model. Antiproliferative high-output NO generation inhibits proproliferative ODC

  4. Sigma 1 Receptor Agonists Act as Neuroprotective Drugs Through Inhibition of Inducible Nitric Oxide Synthase

    Microsoft Academic Search

    Kamila Vagnerova; Patricia D. Hurn; Anish Bhardwaj; Jeffrey R. Kirsch

    2006-01-01

    Postischemic administration of the sigma-1 agonists reduces ischemic brain injury; however, the mechanism is unclear. We hypothesized that the sigma-1 agonist ()isoform of pentazocine (P()) reduces damage in part by ameliorating cell death mediated via inducible nitric oxide synthase (iNOS) and that the ()isoform (P()) lacks this effect. We compared treatment with P() with or without the iNOS inhibitor aminoguanidine

  5. Ghrelin Induces Growth Hormone (GH) Secretion via Nitric Oxide (NO)\\/cGMP Signaling

    Microsoft Academic Search

    F. Rodriguez-Pacheco; R. M. Luque; S. García-Navarro; F. Gracia-Navarro; J. P. Castaño; M. M. Malagón

    2005-01-01

    Ghrelin, a recently discovered 28-aa peptide, stimulates GH release through a mechanism involving PLC- and cAMP-related signaling pathways. Recently, nitric oxide (NO) and its mediator, cGMP, have been shown to be required for the response of somatotropes to various regulators (GHRH, somatostatin, leptin). Here, we explore the possible role of the NO synthase (NOS)\\/NO\\/guanylate cyclase (GC)\\/cGMP signaling pathway in ghrelin-induced

  6. Mechanisms involved in the nitric oxide-induced vasorelaxation in porcine prostatic small arteries

    Microsoft Academic Search

    Vítor S. Fernandes; Ana Martínez-Sáenz; Paz Recio; Ana S. F. Ribeiro; Ana Sánchez; María Pilar Martínez; Ana Cristina Martínez; Albino García-Sacristán; Luis M. Orensanz; Dolores Prieto; Medardo Hernández

    Benign prostatic hypertrophy has been known to be related with glandular ischemia processes, and nitric oxide (NO) is a potent\\u000a vasodilator agent. Therefore, the current study investigates the mechanisms underlying the NO-induced vasorelaxation in pig\\u000a prostatic small arteries. In microvascular myographs, relaxation to electrical field stimulation (EFS), or to exogenous (S)-nitroso-N-acetylpenicillamine (SNAP) and acetylcholine (ACh), was observed on noradrenaline-precontracted prostatic

  7. Aortic Connexin43 Is Decreased During Hypertension Induced by Inhibition of Nitric Oxide Synthase

    Microsoft Academic Search

    Jacques-Antoine Haefliger; Paolo Meda; Andrea Formenton; Philippe Wiesel; Anne Zanchi; Hans R. Brunner; Pascal Nicod; Daniel Hayoz

    Connexin43 (Cx43), the predominant gap junction protein in vessels and heart, is involved in the control of cell-to-cell communication and is thought to modulate the contractility of the vascular wall and the electrical coupling of cardiac myocytes. We have investigated the effects of arterial hypertension induced by inhibition of nitric oxide synthase on the expression of Cx43 in aorta and

  8. Expression of Inducible Nitric Oxide Synthase in Smooth Muscle Cells From Rat Penile Corpora Cavernosa

    Microsoft Academic Search

    ALIDA HUNG; DOLORES VERNET; YINING XIE; TRIPATHI RAJAVASHISTH; ANTONIO RODRIGUEZ; JACOB RAJFER; STOR F. GONZALEZ-CADAVID

    Nitric oxide (NO), the main mediator of penile erection, isassumedto besynthesizedin thepenisbytheneuronalconstitutive nitricoxidesynthase(nNOS).However,nNOShasnotbeenidentified in the penile smooth muscle,the target of NOaction.TheotherNOS isozymes,the inducible NOS (iNOS)andtheendothelialNOS (eNOS) have not been reported in any penile tissue. The smooth muscle vascularand trabeculartissue from rat corpora cavemosais rep- resentedin vitro by cell cultures designated RPSMC. To determine whetheriNOS can be expressedin penilesmooth muscle,RPSMC were

  9. Involvement of Nitric Oxide, Neurotrophins and HPA Axis in Neurobehavioural Alterations Induced by Prenatal Stress.

    PubMed

    Maur, Damian G; Pascuan, Cecilia G; Genaro, Ana M; Zorrilla-Zubilete, Maria A

    2015-01-01

    Several studies suggest that negative emotions during pregnancy generate adverse effects on the cognitive, behavioural and emotional development of the descendants. The psychoneuroendocrine pathways involve the transplacentary passage of maternal glucocorticoids in order to influence directly on fetal growth and brain development.Nitric oxide is a gaseous neurotransmitter that plays an important role in the control of neural activity by diffusing into neurons and participates in learning and memory processes. It has been demonstrated that nitric oxide is involved in the regulation of corticosterone secretion. Thus, it has been found that the neuronal isoform of nitric oxide synthase (nNOS) is an endogenous inhibitor of glucocorticoid receptor (GR) in the hippocampus and that nNOS in the hippocampus may participate in the modulation of hypothalamic-pituitary-adrenal axis activity via GR.Neurotrophins are a family of secreted growth factors consisting of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin 3 (NT3) and NT4. Although initially described in the nervous system, they regulate processes such as cell survival, proliferation and differentiation in several other compartments. It has been demonstrated that the NO-citrulline cycle acts together with BDNF in maintaining the progress of neural differentiation.In the present chapter, we explore the interrelation between nitric oxide, glucocorticoids and neurotrophins in brain areas that are key structures in learning and memory processes. The participation of this interrelation in the behavioural and cognitive alterations induced in the offspring by maternal stress is also addressed. PMID:25287536

  10. Nitric Oxide-Induced Polycystic Ovaries in The Wistar Rat

    PubMed Central

    Hassani, Fatemeh; 1, Ph.D. 1; Jalali Nadoushan, Mohammad Reza; Yazdi, Poopak Eftekhari

    2012-01-01

    Background Nitric oxide (NO) involves in polycystic ovary syndrome (PCOS), a cause of infertility in women during the reproductive age. The PCOS is now categorized as an inflammatory phenomenon. The aim of this study was to evaluate the role of NO, a proinflammatory agent, in this syndrome at histological and biochemical levels. Materials and Methods In this experimental study, animals were female Wistar rats (weighing 200-250 g) kept under standard conditions. L-Arginine (50-200 mg/kg), a precursor of NO, was injected intra-peritoneally (i.p.) through a period ranging from 9 to14 days/ once a day. The rats' estrous cycle was studied using Papanicolaou test; those showing phase of Diestrous were grouped into experimental and control groups. The control group solely received saline (1 ml/kg, i.p.) throughout all experiments. To evaluate the inflammatory effect of NO, the rats were treated an anti-inflammatory agent, naloxone hydrochloride (0.4 mg/kg, i.p.), prior to L-arginine. At the end of the treatment period all animals’ ovaries were assessed for histopathological and histochemical investigations. Also, activation of NO synthase (NOS) in the experiments was studied using NADPH-diaphorase technique. Results The ovaries of rats treated with L-arginine showed polycystic characteristics in contrast to those collected from control or naloxone pretreated groups, based on image analysis. A difference in enzyme activation was also shown in the sections that belonged to the groups that received L-arginine when compared with the pre-naloxone and control groups. Conclusion Based on these results, we believe that NO may play a major role in the pathophysiology of PCOS. PMID:25493168

  11. Manganese-induced effects on cerebral trace element and nitric oxide of Hyline cocks.

    PubMed

    Liu, Xiaofei; Zuo, Nan; Guan, Huanan; Han, Chunran; Xu, Shi Wen

    2013-08-01

    Exposure to Manganese (Mn) is a common phenomenon due to its environmental pervasiveness. To investigate the Mn-induced toxicity on cerebral trace element levels and crucial nitric oxide parameters on brain of birds, 50-day-old male Hyline cocks were fed either a commercial diet or a Mn-supplemented diet containing 600, 900, 1,800 mg kg(-1). After being treated with Mn for 30, 60, and 90 days, the following were determined: the changes in contents of copper (Cu), iron (Fe), zinc (Zn), calcium (Ca), selenium (Se) in brain; inducible nitric oxide synthase-nitric oxide (iNOS-NO) system activity in brain; and histopathology and ultrastructure changes of cerebral cortex. The results showed that Mn was accumulated in brain and the content of Cu and Fe increased. However, the levels of Zn and Se decreased and the Ca content presented no obvious regularity. Exposure to Mn significantly elevated the content of NO and the expression of iNOS mRNA. Activity of total NO synthase (T NOS) and iNOS appeared with an increased tendency. These findings suggested that Mn exposure resulted in the imbalance of cerebral trace elements and influenced iNOS in the molecular level, which are possible underlying nervous system injury mechanisms induced by Mn exposure. PMID:23813426

  12. Eriobotrya japonica leaf and its triterpenes inhibited lipopolysaccharide-induced cytokines and inducible enzyme production via the nuclear factor-kappaB signaling pathway in lung epithelial cells.

    PubMed

    Lee, Chang-Hsien; Wu, Shih-Lu; Chen, Jaw-Chyun; Li, Chia-Cheng; Lo, Hsin-Yi; Cheng, Wen-Yu; Lin, Jaung-Geng; Chang, Yung-Hsien; Hsiang, Chien-Yun; Ho, Tin-Yun

    2008-01-01

    Pulmonary inflammation is a characteristic of many lung diseases. Increased levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and proinflammatory cytokines, such as interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha) and IL-8, have been correlated with lung inflammation. In this study, we used lipopolysaccharide (LPS) to induce iNOS, COX-2, and cytokines (TNF-alpha, IL-1beta, and IL-8) productions in human lung epithelial cells (A-549). Leaf of Eriobotrya japonica (Pi-Pa-Ye, PPY), a traditional Chinese medicine for the treatment of pulmonary inflammatory diseases, was capable of suppressing LPS-induced cytokine productions in a dose-dependent manner. Moreover, the suppression of PPY on the cytokine productions resulted from the inhibition of inhibitory kappaB-alpha phosphorylation and nuclear factor-kappaB (NF-kappaB) activation. Analysis of the anti-inflammatory effects of ursolic acid and oleanolic acid, the triterpene compounds present in PPY, showed that ursolic acid significantly inhibited LPS-induced IL-8 production, NF-kappaB activation, and iNOS mRNA expression, whereas oleanolic acid did not have these effects. In conclusion, our findings suggested the potential mechanisms of PPY and its active component, ursolic acid, in the treatment of pulmonary inflammation. PMID:19051345

  13. The Endogenous Nitric Oxide Mediates Selenium-Induced Phytotoxicity by Promoting ROS Generation in Brassica rapa

    PubMed Central

    Hu, Liang-Bin; Li, You-Qin; Chen, Jian; Yang, Li-Fei

    2014-01-01

    Selenium (Se) is suggested as an emerging pollutant in agricultural environment because of the increasing anthropogenic release of Se, which in turn results in phytotoxicity. The most common consequence of Se-induced toxicity in plants is oxidative injury, but how Se induces reactive oxygen species (ROS) burst remains unclear. In this work, histofluorescent staining was applied to monitor the dynamics of ROS and nitric oxide (NO) in the root of Brassica rapa under Se(IV) stress. Se(IV)-induced faster accumulation of NO than ROS. Both NO and ROS accumulation were positively correlated with Se(IV)-induced inhibition of root growth. The NO accumulation was nitrate reductase (NR)- and nitric oxide synthase (NOS)-dependent while ROS accumulation was NADPH oxidase-dependent. The removal of NO by NR inhibitor, NOS inhibitor, and NO scavenger could alleviate Se(IV)-induced expression of Br_Rbohs coding for NADPH oxidase and the following ROS accumulation in roots, which further resulted in the amelioration of Se(IV)-induced oxidative injury and growth inhibition. Thus, we proposed that the endogenous NO played a toxic role in B. rapa under Se(IV) stress by triggering ROS burst. Such findings can be used to evaluate the toxic effects of Se contamination on crop plants. PMID:25333984

  14. Macrophage activating factor(s) secreted by mitogen stimulated goldfish kidney leukocytes synergize with bacterial lipopolysaccharide to induce nitric oxide production in teleost macrophages

    Microsoft Academic Search

    N. F. Neumann; D. Fagan; M. Belosevic

    1995-01-01

    Recent studies in our laboratory demonstrated that fish macrophages produce nitric oxide. To elucidate the mechanisms which regulate nitric oxide production in teleosts, we examined whether macrophage activating factors (MAFs) secreted by mitogen stimulated leukocytes, induced nitric oxide production in a long-term cultured macrophage cell line and in primary cultures of kidney macrophages from the goldfish. The results indicate that

  15. Pu-erh Tea Reduces Nitric Oxide Levels in Rats by Inhibiting Inducible Nitric Oxide Synthase Expression through Toll-Like Receptor 4

    PubMed Central

    Xu, Yang; Wang, Guan; Li, Chunjie; Zhang, Min; Zhao, Hang; Sheng, Jun; Shi, Wei

    2012-01-01

    Pu-erh tea undergoes a unique fermentation process and contains theabrownins, polysaccharides and caffeine; although it is unclear about which component is associated with the down regulation of nitric oxide levels or how this process is mediated. To address this question we examined the effects of pu-erh tea on nitric oxide synthase (NOS) genes. Cohorts of rats were separately given four-week treatments of water as control, pu-erh tea, or the tea components: theabrownins, caffeine or polysaccharides. Five experimental groups were injected with lipopolysaccharides (LPS) to induce nitric oxide (NO) production, while the corresponding five control groups were injected with saline as a negative control. The serum and liver NO concentrations were examined and the NOS expression of both mRNA and protein was measured in liver. The results showed that the rats which were fed pu-erh tea or polysaccharides had lower levels of NO which corresponded with the down-regulation of inducible nitric oxide synthase (iNOS) expression. We further demonstrate that this effect is mediated through reduction of Toll-like receptor 4 (TLR4) signaling. Thus we find that the polysaccharide components in pu-erh tea reduce NO levels in an animal model by inhibiting the iNOS expression via signaling through TLR4. PMID:22837686

  16. Pu-erh tea reduces nitric oxide levels in rats by inhibiting inducible nitric oxide synthase expression through toll-like receptor 4.

    PubMed

    Xu, Yang; Wang, Guan; Li, Chunjie; Zhang, Min; Zhao, Hang; Sheng, Jun; Shi, Wei

    2012-01-01

    Pu-erh tea undergoes a unique fermentation process and contains theabrownins, polysaccharides and caffeine; although it is unclear about which component is associated with the down regulation of nitric oxide levels or how this process is mediated. To address this question we examined the effects of pu-erh tea on nitric oxide synthase (NOS) genes. Cohorts of rats were separately given four-week treatments of water as control, pu-erh tea, or the tea components: theabrownins, caffeine or polysaccharides. Five experimental groups were injected with lipopolysaccharides (LPS) to induce nitric oxide (NO) production, while the corresponding five control groups were injected with saline as a negative control. The serum and liver NO concentrations were examined and the NOS expression of both mRNA and protein was measured in liver. The results showed that the rats which were fed pu-erh tea or polysaccharides had lower levels of NO which corresponded with the down-regulation of inducible nitric oxide synthase (iNOS) expression. We further demonstrate that this effect is mediated through reduction of Toll-like receptor 4 (TLR4) signaling. Thus we find that the polysaccharide components in pu-erh tea reduce NO levels in an animal model by inhibiting the iNOS expression via signaling through TLR4. PMID:22837686

  17. A Neurovascular Transmission Model for Acupuncture-induced Nitric Oxide

    Microsoft Academic Search

    Sheng-Hsiung Hsiao; Li-Jen Tsai

    2008-01-01

    Acupuncture is the practice of inserting needles into the body to reduce pain or induce anesthesia. More broadly, acupuncture is a family of procedures involving the stimulation of anatomical locations on or in the skin by a variety of techniques. Employing acupuncture to treat human disease or maintain bodily condition has been practiced for thousands of years. However, the mechanism(s)

  18. Nitric Oxide Induces Rapid, Calcium-Dependent Release of Vesicular

    E-print Network

    Newman, Eric A.

    may act as an intercellular messenger between neurons, astrocytes, and other brain cells (Dinerman et Rat Astrocytes ANNA BAL-PRICE,1 * ZAHID MONEER,2 AND GUY C. BROWN1 1 Department of Biochemistry and ATP release from cultured rat cortical astrocytes. NO-induced glutamate release was prevented

  19. 3,3'-Diindolylmethane inhibits lipopolysaccharide-induced microglial hyperactivation and attenuates brain inflammation.

    PubMed

    Kim, Hyo Won; Kim, Jiyoung; Kim, Jaekyoon; Lee, Siyoung; Choi, Bo-Ryoung; Han, Jung-Soo; Lee, Ki Won; Lee, Hyong Joo

    2014-01-01

    Recent studies have revealed that microglial hyperactivation and neuroinflammation are implicated in development and progression of neurodegenerative diseases. In this study, we examined the beneficial effects of 3,3'-diindolylmethane (DIM) and indole-3-carbinol (I3C), dietary components found in cruciferous vegetables, on brain inflammation. DIM, a major metabolite of I3C, suppressed lipopolysaccharide (LPS)-induced expression of inducible nitric oxide synthase and cyclooxygenase-2 in BV-2 microglia, but I3C did not. DIM, but not I3C, attenuated DNA-binding activity of nuclear factor-?B (NF-?B) and phosphorylation of inhibitor of ?B, suggesting that DIM might inhibit microglial hyperactivation by attenuating inflammatory transcription factor NF-?B. In addition, DIM, but not I3C, protected primary cortical neurons from inflammatory toxicity induced by the conditioned media from LPS-stimulated BV-2 microglia, indicating that DIM might attenuate microglial hyperactivation-mediated neuronal death. In an in vivo model of neuroinflammation, DIM suppressed LPS-induced brain inflammation in mouse hippocampus, as determined by the number of Iba-1-positive cells and the mRNA expression of F4/80. Taken together, these results suggest that DIM may have beneficial potential against brain inflammation and neurodegenerative diseases through the negative regulation of the NF-?B signal pathway in microglia. PMID:24162184

  20. Nerve-induced tachykinin-mediated vasodilation in skeletal muscle is dependent on nitric oxide formation.

    PubMed

    Persson, M G; Hedqvist, P; Gustafsson, L E

    1991-12-01

    Nerve-induced vasodilatation was studied by intravital microscopy of the rabbit tenuissimus muscle, pretreated with pancuronium, phentolamine, and guanethidine. Nerve stimulation of the tenuissimus nerve induced a vasodilatation which was frequency and pulse duration-dependent and insensitive to atropine and propanolol but abolished by tetrodotoxin. The nitric oxide synthase inhibitor, N omega-nitro-L-arginine methyl ester (L-NAME, 100 microM), but not its enantiomer, D-NAME, markedly inhibited the vasodilation induced by nerve stimulation or by exogenous substance P or neurokinin A. Vasodilatation due to calcitonin gene-related peptide, prostaglandin E2 or nitroprusside was unaffected. The substance P antagonist, spantide (30 microM), significantly attenuated nerve-induced vasodilatation, in parallel with L-NAME. Our results indicate that nerve-induced vasodilatation in skeletal muscle can be attributed to the release of substance P and/or other tachykinins and that nitric oxide subsequently mediates the response to endogenous tachykinins released from nerves. PMID:1726318

  1. Cryptococcus neoformans fails to induce nitric oxide synthase in primed murine macrophage-like cells.

    PubMed Central

    Naslund, P K; Miller, W C; Granger, D L

    1995-01-01

    Nitric oxide (NO) is a microbiostatic gas generated by activated murine macrophages. Cytokine signals, gamma interferon (IFN-gamma) and tumor necrosis factor alpha (TNF-alpha) act synergistically to induce production of a macrophage nitric oxide synthase (NOS). A variety of intracellular pathogens, when recognized by macrophages primed with IFN-gamma, induce NOS by eliciting TNF-alpha secretion, which then functions as a positive autocrine signal. In cell culture assays, a murine macrophage cell line (J774), primed with IFN-gamma, was tested for NOS induction upon challenge with virulent Cryptococcus neoformans. C. neoformans failed to induce macrophage NOS as measured by nitrite production. This was true irrespective of the C. neoformans-to-J774 ratio. Other nonpathogenic Cryptococcus species likewise failed to induce NOS, yet Saccharomyces cerevisiae, Histoplasma capsulatum, and Candida albicans were efficient inducers of NOS. Conditions which promoted attachment and/or phagocytosis of C. neoformans did not lead to NOS induction (including opsonization with specific antibodies against C. neoformans). Assays for transcriptional repressors of NOS were negative. Tests for consumption of nitrite by measurement of additional products of NOS induction were negative. No TNF-alpha was detected by enzyme-linked immunosorbent assay in supernatants from C. neoformans-J774 cocultures. A mutant C. neoformans strain with a minimal, but visible, polysaccharide capsule also failed to induce NOS; however, several nonencapsulated mutants of C. neoformans did induce NOS. Failure of C. neoformans to act as an inducer of NOS may be related to the virulence of this pathogen in mice; C. neoformans is a unique example of a facultative intracellular pathogen which fails to induce NOS in primed macrophages. The mechanism appears to involve the failure of TNF-alpha secretion once the macrophage comes in contact with the fungus. The presence of the polysaccharide capsule appears to mask the signal necessary for TNF-alpha secretion and, ultimately, NOS induction. PMID:7534274

  2. Citral inhibits lipopolysaccharide-induced acute lung injury by activating PPAR-?.

    PubMed

    Shen, Yongbin; Sun, Zhanfeng; Guo, Xiaotong

    2015-01-15

    Citral, a component of lemongrass oil, has been reported to have many pharmacological activities such as anti-bacterial and anti-inflammatory effects. However, the effects of citral on acute lung injury (ALI) and the molecular mechanisms have not been reported. The aim of this study was to detect the effects of citral on lipopolysaccharide (LPS)-induced acute lung injury and investigate the molecular mechanisms. LPS-induced acute lung injury model was used to detect the anti-inflammatory effect of citral in vivo. The alveolar macrophages were used to investigate the molecular mechanism of citral in vitro. The results showed that pretreatment with citral remarkably attenuated pulmonary edema, histological severities, TNF-?, IL-6 and IL-1? production in LPS-induced ALI in vivo. In vitro, citral inhibited LPS-induced TNF-?, IL-6 and IL-1? production in alveolar macrophages. LPS-induced NF-?B activation was also inhibited by citral. Furthermore, we found that citral activated PPAR-? and the anti-inflammatory effects of citral can be reversed by PPAR-? antagonist GW9662. In conclusion, this is the first to demonstrate that citral protects LPS-induced ALI in mice. The anti-inflammatory mechanism of citral is associated with activating PPAR-?, thereby inhibiting LPS-induced inflammatory response. PMID:25281205

  3. Endogenous nitric oxide modifies antigen-induced microvascular leakage in sensitized guinea pig airways.

    PubMed

    Miura, M; Ichinose, M; Kageyama, N; Tomaki, M; Takahashi, T; Ishikawa, J; Ohuchi, Y; Oyake, T; Endoh, N; Shirato, K

    1996-07-01

    To examine the role of endogenous nitric oxide in allergic airway inflammation, we investigated the effect of a nitric oxide synthase inhibitor, N omega-nitro-L-arginine methyl ester (l-NAME), on antigen-induced airway microvascular leakage in actively sensitized guinea pigs by using Evans blue dye. Three weeks after sensitization with ovalbumin (10 micrograms), the tracheas were cannulated, and lungs were artificially ventilated. Animals were pretreated with atropine and propranolol (both 1 mg/kg, intravenously) to avoid neural modification. Ovalbumin inhalation (3 mg/ml, 1 minute) challenge caused significant microvascular leakage in all airways portions, which was significantly suppressed in a dose-dependent manner by pretreatment with intravenous injection of L-NAME (1 and 10 mg/kg) but not with the inactive enantiomer D-NAME (10 mg/kg). This inhibition by L-NAME was significantly reversed by co-administration of L-arginine (100 mg/kg, intravenously). Pretreatment with a vasoconstrictor, phenylephrine (20 micrograms/kg, intravenously), had no inhibitory effects on antigen-induced airway microvascular leakage despite increasing systemic blood pressure. Inhalation of representative mast cell-derived mediators, histamine (2 mg/ml, 1 minute) or leukotriene D4 (5 micrograms/ml, 1 minute), produced significant microvascular leakage in all airways. L-NAME (10 mg/kg, intravenously) partially but significantly inhibited leukotriene D4-induced leakage, whereas histamine-induced leakage was not affected. These results suggest that endogenous nitric oxide acts to increase airway microvascular leakage after airway allergic reaction. PMID:8765828

  4. Comparison of inducible nitric oxide synthase activity in pancreatic islets of young and aged rats

    PubMed Central

    Farrokhfall, Khadije; Hashtroudi, Mehri Seyed; Ghasemi, Asghar; Mehrani, Hossein

    2015-01-01

    Objective(s): Some pathologic situations such as diabetes and metabolic syndrome are associated with alternation in nitric oxide level. Incidence of these condition increases with aging. On the other hand, insulin secretion is modulated by nitric oxide, and nitric oxide synthase (NOS) activity is also altered in diabetes. In this study, modification in the enzyme activity associated with aging and also optimized procedure for islet NOS assay was investigated. Materials and Methods: Male Wistar rats were randomly divided in two experimental groups: A: adult rats; were 4 month old and B: old rats; were 12 month old. In all groups, plasma glucose, insulin and NOX (nitrite + nitrate = NOX) were measured, and also insulin secretion in isolated pancreatic islet with or without L-NAME was investigated. Furthermore, the inducible NOS activity with L-citrulline measurement in islets was measured. Results: L-citrulline was quantified using one step HPLC column. Aging induced hyperglycemia (P<0.05) and excess plasma NOX (17.74 ± 1.664 and 26.25 ± 2.166 ?mol/l in A and B groups respectively, P<0.05) with unaltered plasma insulin. Islet insulin secretion was significantly reduced in aging rats. L-NAME induced islet insulin secretion especially in aging rats (P=0.003). Inducible NOS activity in islets of aging rats was significantly higher than adult rats (1.082 ± 0.084 and 6.277 ± 0.475 pmol/min per mg protein in adult and aging rats, respectively, P<0.001). Conclusion: These findings show that decreased in islet insulin secretion may be related to increase in iNOS activity in islets, which follows impaired carbohydrate metabolism in aging. PMID:25810884

  5. Defective Nitric Oxide Effector Functions Lead to Extreme Susceptibility of Trypanosoma cruzi-Infected Mice Deficient in Gamma Interferon Receptor or Inducible Nitric Oxide Synthase

    Microsoft Academic Search

    CHRISTOPH HOLSCHER; GABRIELE KOHLER; UWE MULLER; HORST MOSSMANN; GUNTER A. SCHAUB; FRANK BROMBACHER

    deficient for the gamma interferon (IFN-g) receptor (IFN-gR2\\/2) or deficient for inducible nitric oxide synthase (iNOS2\\/2). Both lines were highly susceptible, with similar and dramatically increased parasite burdens and severe histopathology and were incapable of surviving even very low doses, exhibiting similar mortality kinetics. This pathophysiological correlation has a common cause, since both mutant mouse strains were unable to respond

  6. Nitric oxide mediates alginate oligosaccharides-induced root development in wheat (Triticum aestivum L.).

    PubMed

    Zhang, Yunhong; Liu, Hang; Yin, Heng; Wang, Wenxia; Zhao, Xiaoming; Du, Yuguang

    2013-10-01

    Alginate oligosaccharides (AOS), which are marine oligosaccharides, are involved in regulating plant root growth, but the promotion mechanism for AOS remains unclear. Here, AOS (10-80 mg L(-1)) were found to induce the generation of nitric oxide (NO) in the root system of wheat (Triticum aestivum L.), which promoted the formation and elongation of wheat roots in a dose-dependent manner. NO inhibitors suggested that nitrate reductase (NR), rather than nitric oxide synthase (NOS), was essential for AOS-induced root development. Further studies confirmed that AOS-induced NO generation in wheat roots by up-regulating the gene expression and enzyme activity of NR at the post-transcriptional level. The anatomy and RT-PCR results showed that AOS accelerated the division and growth of stele cells, leading to an increase in the ratio of stele area to root transverse area. This could be inhibited by the NR inhibitor, sodium tungstate, which indicated that NO catalyzed by the NR was involved in AOS regulation of root development. Taken together, in the early stage of AOS-induced root development, NO generation was a novel mechanism by which AOS regulated plant growth. The results also showed that this marine resource could be widely used for crop development. PMID:23872742

  7. Molecular cloning and expression of inducible nitric oxide synthase from human hepatocytes.

    PubMed Central

    Geller, D A; Lowenstein, C J; Shapiro, R A; Nussler, A K; Di Silvio, M; Wang, S C; Nakayama, D K; Simmons, R L; Snyder, S H; Billiar, T R

    1993-01-01

    Nitric oxide is a short-lived biologic mediator for diverse cell types. Synthesis of an inducible nitric oxide synthase (NOS) in murine macrophages is stimulated by lipopolysaccharide (LPS) and interferon gamma. In human hepatocytes, NOS activity is induced by treatment with a combination of tumor necrosis factor, interleukin 1, interferon gamma, and LPS. We now report the molecular cloning and expression of an inducible human hepatocyte NOS (hep-NOS) cDNA. hep-NOS has 80% amino acid sequence homology to macrophage NOS (mac-NOS). Like other NOS isoforms, recognition sites for FMN, FAD, and NADPH are present, as well as a consensus calmodulin binding site. NOS activity in human 293 kidney cells transfected with hep-NOS cDNA is diminished by Ca2+ chelation and a calmodulin antagonist, reflecting a Ca2+ dependence not evident for mac-NOS. Northern blot analysis with hep-NOS cDNA reveals a 4.5-kb mRNA in both human hepatocytes and aortic smooth muscle cells following stimulation with LPS and cytokines. Human genomic Southern blots probed with human hep-NOS and human endothelial NOS cDNA clones display different genomic restriction enzyme fragments, suggesting distinct gene products for these NOS isoforms. hep-NOS appears to be an inducible form of NOS that is distinct from mac-NOS as well as brain and endothelial NOS isozymes. Images Fig. 2 Fig. 3 Fig. 4 PMID:7682706

  8. Nitric oxide: Mediator of nonadrenergic noncholinergic nerve-induced responses of opossum esophageal muscle

    SciTech Connect

    Murray, J.; Du, C.; Conklin, J.L.; Ledlow, A.; Bates, J.N. (Univ. of Iowa, Iowa City (United States))

    1991-03-15

    Nonadrenergic noncholinergic (NANC) nerves of the opossum esophagus mediate relaxation of circular muscle from the lower esophageal sphincter (LES) and the off contraction of circular esophageal muscle. The latencies between the end of the stimulus and the off contraction describe a gradient such that the latency is longest in muscle from the caudad esophagus. N{sup G}-nitro-L-arginine (L-NNA), an inhibitor of nitric oxide synthase, and nitric oxide were used to test the hypothesis that NO is a mediator of these nerve-induced responses. Both electrical field stimulation (EFS) of intrinsic esophageal nerves and exogenous NO relaxed LES muscle. Only EFS-induced relaxation was inhibited by L-NNA. L-arginine, the substrate for NO synthase, antagonized the inhibitory effect of L-NNA. Exogenous NO neither relaxed nor contracted circular esophageal muscle. Both the amplitude and the latency of the off contraction were diminished by L-NNA. L-arginine antagonized the action of L-NNA. N{sup G}-nitro-L-arginine also attenuated the gradient in the latency of the off response by shortening latencies in muscle form the caudad esophagus. It had no effect on cholinergic nerve-induced contraction of longitudinal esophageal muscle. These data support the hypothesis that NO or an NO-containing compound mediates NANC nerve-induced responses of the esophagus and LES.

  9. Effects of cobalt chloride on nitric oxide and cytokines/chemokines production in microglia.

    PubMed

    Mou, Yan Hua; Yang, Jing Yu; Cui, Nan; Wang, Ji Ming; Hou, Yue; Song, Shuang; Wu, Chun Fu

    2012-05-01

    The involvement of microglial activation in metal neurotoxicity is becoming increasingly recognized. Some metal ions, such as zinc (II) and manganese (II), have been recently reported as microglial activators to induce the release of inflammatory mediators including cytokines, chemokines and nitric oxide (NO) which are involved in the pathogenesis of neurological diseases. Cobalt is essential for human life. However, excessive cobalt is cytotoxic and neurotoxic. In the present study, we determined cobalt-induced production of NO and cytokines/chemokines in N9 cells, a murine microglial cell line. High levels of cobalt significantly up-regulated iNOS mRNA and protein expression, which resulted in the release of NO. Cobalt induced the production of tumor necrosis factor ? (TNF-?) and interleukin-6 (IL-6) in a concentration- and time-dependent manner in both N9 cells and primary mouse microglia and increased lipopolysaccharides (LPS)-induced cytokine production. Further study showed that cobalt induced cytokine production by a mechanism involving both nuclear factor kappa B (NF-?B) and p38 mitogen-activated protein kinase (MAPK) signaling pathways. The involvement of reactive oxygen species (ROS) in microglial activation was also confirmed. These findings suggested that cobalt neurotoxicity should be attributed not only directly to neuronal damage but also indirectly to microglial activation which might potentiate neuronal injury via elevation of proinflammatory mediator levels. PMID:22472292

  10. A recombinant vaccinia virus encoding inducible nitric oxide synthase is attenuated in vivo.

    PubMed Central

    Rolph, M S; Cowden, W B; Medveczky, C J; Ramshaw, I A

    1996-01-01

    To investigate the role of nitric oxide during vaccinia virus (VV) infection of mice, a recombinant VV encoding the inducible nitric oxide synthase (iNOS) gene (VV-HA-iNOS) was constructed. Following infection of immunocompromised or immunocompetent mice, the virus was highly attenuated compared with a control recombinant VV. Athymic and sublethally irradiated mice survived infection with 10(7) PFU of VV-HA-iNOS, a dose that resulted in uniform mortality in mice infected with the control recombinant VV. Attenuated virus growth was evident as early as 24 h following infection, suggesting that NO had direct antiviral activity. We have previously shown that treatment of mice with the inhibitor of NO production N(G)-methyl-L-arginine did not influence the course of VV infection in mice. The present study has indicated that NO can potentially exert an antiviral effect during murine VV infection. We propose that during VV infection, nitric oxide production contributes to the control of virus growth, but that in its absence, other antiviral mechanisms are sufficient to mediate fully effective virus clearance. PMID:8892888

  11. Interaction between Nitric Oxide Synthase Inhibitor Induced Oscillations and the Activation Flow Coupling Response

    PubMed Central

    Ances, Beau M.; Greenberg, Joel. H.; Detre, John A.

    2009-01-01

    The role of nitric oxide (NO) in the activation-flow coupling (AFC) response to periodic electrical forepaw stimulation was investigated using signal averaged laser Doppler (LD) flowmetry. LD measures of calculated cerebral blood flow (CBF) were obtained both prior and after intra-peritoneal administration of the non-selective nitric oxide synthase (NOS) inhibitor, NG-nitro-L-arginine (L-NNA) (40 mg/kg). Characteristic baseline low frequency vasomotion oscillations (0.17 Hz) were observed after L-NNA administration. These LDCBF oscillations were synchronous within but not between hemispheres. L-NNA reduced the magnitude of the AFC response (p< 0.05) for longer stimuli (1 minute) with longer inter-stimulus intervals (2 minutes). In contrast, the magnitude of the AFC response for short duration stimuli (4 seconds) with short inter-stimulus intervals (20 seconds) was augmented (p < 0.05) after L-NNA. An interaction occurred between L-NNA induced vasomotion oscillations and the AFC response with the greatest increase occurring at the stimulus harmonic closest to the oscillatory frequency. Nitric oxide may therefore modulate the effects of other vasodilators involved in vasomotion oscillations and the AFC response. PMID:19900416

  12. Rabdosia japonica var. glaucocalyx Flavonoids Fraction Attenuates Lipopolysaccharide-Induced Acute Lung Injury in Mice

    PubMed Central

    Xu, Nai-yu; Li, Xian-lun; Xia, Long; Zhang, Jian; Liang, Zhi-tao; Zhao, Zhong-zhen; Chen, Dao-feng

    2014-01-01

    Rabdosia japonica var. glaucocalyx (Maxim.) Hara, belonging to the Labiatae family, is widely used as an anti-inflammatory and antitumor drug for the treatment of different inflammations and cancers. Aim of the Study. To investigate therapeutic effects and possible mechanism of the flavonoids fraction of Rabdosia japonica var. glaucocalyx (Maxim.) Hara (RJFs) in acute lung injury (ALI) mice induced by lipopolysaccharide (LPS). Materials and Methods. Mice were orally administrated with RJFs (6.4, 12.8, and 25.6?mg/kg) per day for 7 days, consecutively, before LPS challenge. Lung specimens and the bronchoalveolar lavage fluid (BALF) were isolated for histopathological examinations and biochemical analysis. The level of complement 3 (C3) in serum was quantified by a sandwich ELISA kit. Results. RJFs significantly attenuated LPS-induced ALI via reducing productions of the level of inflammatory mediators (TNF-?, IL-6, and IL-1?), and significantly reduced complement deposition with decreasing the level of C3 in serum, which was exhibited together with the lowered myeloperoxidase (MPO) activity and nitric oxide (NO) and protein concentration in BALF. Conclusions. RJFs significantly attenuate LPS-induced ALI via reducing productions of proinflammatory mediators, decreasing the level of complement, and reducing radicals. PMID:25013450

  13. Rabdosia japonica var. glaucocalyx Flavonoids Fraction Attenuates Lipopolysaccharide-Induced Acute Lung Injury in Mice.

    PubMed

    Chu, Chun-Jun; Xu, Nai-Yu; Li, Xian-Lun; Xia, Long; Zhang, Jian; Liang, Zhi-Tao; Zhao, Zhong-Zhen; Chen, Dao-Feng

    2014-01-01

    Rabdosia japonica var. glaucocalyx (Maxim.) Hara, belonging to the Labiatae family, is widely used as an anti-inflammatory and antitumor drug for the treatment of different inflammations and cancers. Aim of the Study. To investigate therapeutic effects and possible mechanism of the flavonoids fraction of Rabdosia japonica var. glaucocalyx (Maxim.) Hara (RJFs) in acute lung injury (ALI) mice induced by lipopolysaccharide (LPS). Materials and Methods. Mice were orally administrated with RJFs (6.4, 12.8, and 25.6?mg/kg) per day for 7 days, consecutively, before LPS challenge. Lung specimens and the bronchoalveolar lavage fluid (BALF) were isolated for histopathological examinations and biochemical analysis. The level of complement 3 (C3) in serum was quantified by a sandwich ELISA kit. Results. RJFs significantly attenuated LPS-induced ALI via reducing productions of the level of inflammatory mediators (TNF- ? , IL-6, and IL-1 ? ), and significantly reduced complement deposition with decreasing the level of C3 in serum, which was exhibited together with the lowered myeloperoxidase (MPO) activity and nitric oxide (NO) and protein concentration in BALF. Conclusions. RJFs significantly attenuate LPS-induced ALI via reducing productions of proinflammatory mediators, decreasing the level of complement, and reducing radicals. PMID:25013450

  14. The inhibition of lipopolysaccharide-induced macrophage inflammation by 4 compounds in Hypericum perforatum extract is partially dependent on the activation of SOCS3

    PubMed Central

    Huang, Nan; Rizshsky, Ludmila; Hauck, Catherine C.; Nikolau, Basil J.; Murphy, Patricia A.; Birt, Diane F.

    2012-01-01

    Our previous studies found that 4 compounds, namely pseudohypericin, amentoflavone, quercetin, and chlorogenic acid in Hypericum perforatum ethanol extract synergistically inhibited lipopolysaccharide (LPS)-induced macrophage production of prostaglandin E2 (PGE2). Microarray studies led us to hypothesize that these compounds inhibited PGE2 production by activating suppressor of cytokine signaling 3 (SOCS3). In the current study we used siRNA to knockdown the expression of SOCS3 in RAW 264.7 macrophages and investigated the impact of H. perforatum extract and the 4 compounds on inflammatory mediators and cytokines. We found SOCS3 knockdown significantly compromised the inhibition of PGE2 and nitric oxide (NO) by the 4 compounds, but not by the extract. The 4 compounds, but not the extract decreased interleukin-6 (IL-6) and tumor necrosis factor-? (TNF-?), while both of them lowered interleukine-1?. SOCS3 knockdown further decreased IL-6 and TNF-?. Pseudohypericin was the major contributor to the PGE2 and NO inhibition in cells treated with the 4 compounds and its activity was lost with SOCS3 knockdown. Cyclooxygenase-2 (COX-2) and inducible NO synthase protein expression were not altered by the treatments, while COX-2 activity was decreased by the extract and the 4 compounds and increased by SOCS3 knockdown. In summary, we demonstrated that the 4 compounds inhibited LPS-induced PGE2 and NO through SOCS3 activation. The reduction of PGE2 can be partially attributed to COX-2 enzyme activity, which was significantly elevated with SOCS3 knockdown. At the same time, our results also suggest that constituents in H. perforatum extract were alleviating LPS-induced macrophage response through SOCS3 independent mechanisms. PMID:22245632

  15. Forsythiaside attenuates lipopolysaccharide-induced inflammatory responses in the bursa of Fabricius of chickens by downregulating the NF-?B signaling pathway

    PubMed Central

    CHENG, GUANGDONG; ZHAO, YULIAN; LI, HE; WU, YUE; LI, XIANXIAN; HAN, QIANG; DAI, CHONGSHAN; LI, YANHUA

    2014-01-01

    Forsythiaside, a phenylethanoside product isolated from air-dried fruits of Forsythia suspensa, has been demonstrated to exhibit antioxidant, antibacterial and anti-inflammatory activities in vitro. However, its mechanism and the effects of lipopolysaccharide (LPS)-induced injury on the bursa of Fabricius (BF) of chickens are poorly understood. The present study aimed to investigate the anti-inflammatory effects of forsythiaside on LPS-induced acute inflammation. In addition, the potential molecular mechanisms of forsythiaside were analyzed in the BF, a special immune organ in chickens. Forty 15-day-old chickens were randomly divided into control, LPS and LPS plus forsythiaside (30 or 60 mg/kg) groups (n=10 for each group). In the LPS plus forsythiaside (30 or 60 mg/kg) groups, the chickens were orally administered with forsythiaside at doses of 30 and 60 mg/kg for seven days. At 21 days old, the chickens were intravenously injected with 200 ?g/kg body weight LPS. Chickens in the control and LPS groups were only administered with vehicle or LPS, respectively, at day 21. At 3 h post-injection, the body temperature and nitric oxide (NO) levels were analyzed. In addition, the levels and mRNA expression of pro-inflammatory cytokines, including tumor necrosis factor-? (TNF-?), interleukin-6 (IL-6) and IL-1?, and the mRNA expression of nuclear factor-?B (NF-?B), cyclooxygenase-2 (COX-2) and inducible NO synthase (iNOS), were examined in the BFs isolated from the chickens. The results revealed that forsythiaside was able to attenuate the LPS-induced inflammatory responses in the BFs of the chickens. The mechanisms by which forsythiaside exerted its anti-inflammatory effect were found to correlate with the inhibition of IL-6, IL-1?, TNF-? and COX-2 production, via the inactivation of NF-?B, indicating that the NF-?B-iNOS-NO signaling pathway may be important in this process. PMID:24348786

  16. Fibroproliferation in LPS-induced airway remodeling and bleomycin-induced fibrosis share common patterns of gene expression

    Microsoft Academic Search

    David M. Brass; Ivana V. Yang; Marcus P. Kennedy; Gregory S. Whitehead; Holly Rutledge; Lauranell H. Burch; David A. Schwartz

    2008-01-01

    Chronic LPS inhalation causes submucosal thickening and airway narrowing. To address the hypothesis that environmental airway\\u000a disease is, in part, a fibroproliferative lung disease, we exposed C57BL\\/6 mice daily to LPS by inhalation for up to 2 months\\u000a followed by 1 month of recovery. C57BL\\/6 mice exposed to daily inhaled LPS had significantly enhanced mRNA expression of TGF-?1,\\u000a TIMP-1, fibronectin-1, and pro-collagen

  17. Bisabolol-induced gastroprotection against acute gastric lesions: role of prostaglandins, nitric oxide, and KATP+ channels.

    PubMed

    Bezerra, S B; Leal, L K A M; Nogueira, N A P; Pinto, N A N; Campos, A R

    2009-12-01

    The effects of Matricaria recutita and alpha-bisabolol, a bioactive component from Chamomile species, were investigated against gastric damage induced by absolute ethanol (96%, 1 mL per animal) in rats. The effects of M. recutita extract and alpha-bisabolol on gastric mucosal damage were assessed by determination of changes in mean gastric lesion area. Mechanistic studies were carried out at with 100 mg=kg alpha-bisabolol. We further examined the possible participation of prostaglandins, nitric oxide, and KATP+ channels in its mechanism. M. recutita reduced gastric damage in all doses tested. Alpha-bisabolol at oral doses of 50 and 100 mg=kg markedly attenuated the gastric lesions induced by ethanol to the extent of 87% and 96%, respectively. Pretreatments with the nitric oxide antagonist N-nitro-l-arginine methyl ester (10 mg=kg, i.p.) or with indomethacin, an inhibitor of cyclooxygenase, failed to block effectively the gastroprotective effect of alpha-bisabolol. Furthermore, the alpha-bisabolol effect was significantly reduced in rats pretreated with glibenclamide, an inhibitor of KATP+ channel activation. Thus we provide evidence that alpha-bisabolol reduces the gastric damage induced by ethanol, at least in part, by the mechanism of activation of KATP+ channels. PMID:20041801

  18. Neurotransmitters adenosine triphosphate and noradrenaline induce nitric oxide release in rat vas deferens.

    PubMed

    Vetri, T; Di Maio, R; Bonafede, G; Passafiume, L; Postorino, A

    2000-06-01

    1. In rat vas deferens, electrical field stimulation (EFS) evoked a muscular biphasic tetrodotoxin (TTX)-sensitive contractile response. 2. The amplitude of this response increased with the frequency of stimulation. 3. After each stimulation, nitric oxide (NO) release was assayed and found to be released in a frequency-dependent manner. 4. NO release also occurred after treatment with exogenous neurotransmitters, adenosine 5'-triphosphate (ATP) and noradrenaline (NA). 5. Prazosin and pyridoxalphosphate-6-azophenyl-2',4'-disulphonic acid (PPADS), respective antagonists of alpha1-adrenoceptors and P2x purinoceptors, inhibited NO release induced by NA and ATP. Both prazosin and PPADS inhibited NO release by EFS. 6. TTX failed to modify the NO release induced by exogenous neurotransmitters but abolished the release of NO and contractile response by EFS. 7. EFS and released noradrenaline and ATP induce the release of NO through postjunctional alpha1 -adrenoceptors and P2x-purinoceptors, respectively. PMID:11193001

  19. The Combined Inducible Nitric Oxide Synthase Inhibitor and Free Radical Scavenger Guanidinoethyldisulfide Prevents Multiple Low-Dose StreptozotocinInduced Diabetes In Vivo and Interleukin1??Induced Suppression of Islet Insulin Secretion In Vitro

    Microsoft Academic Search

    Jon G. Mabley; Gary J. Southan; Andrew L. Salzman

    2004-01-01

    Inhibition of inducible nitric oxide synthase has been shown to be antiinflammatory in a variety of disease states. Type I diabetes is an autoimmune disease resulting from the specific destruc- tion of the insulin-producing pancreatic cells. Here we demonstrate that guanidinoethyldisulfide (GED), a combined inducible nitric ox- ide synthase inhibitor and peroxynitrite\\/reactive oxygen species scav- enger reduces the hyperglycemia and

  20. Interleukin-33 Increases Antibacterial Defense by Activation of Inducible Nitric Oxide Synthase in Skin

    PubMed Central

    Jiang, Ziwei; Zhang, Tian; Wang, Yue; Li, Zhiheng; Wu, Yelin; Ji, Shizhao; Xiao, Shichu; Ryffel, Bernhard; Radek, Katherine A.; Xia, Zhaofan; Lai, Yuping

    2014-01-01

    Interleukin-33 (IL-33) is associated with multiple diseases, including asthma, rheumatoid arthritis, tissue injuries and infections. Although IL-33 has been indicated to be involved in Staphylococcus aureus (S. aureus) wound infection, little is known about how IL-33 is regulated as a mechanism to increase host defense against skin bacterial infections. To explore the underlying intricate mechanism we first evaluated the expression of IL-33 in skin from S. aureus-infected human patients. Compared to normal controls, IL-33 was abundantly increased in skin of S. aureus-infected patients. We next developed a S. aureus cutaneous infection mouse model and found that IL-33 was significantly increased in dermal macrophages of infected mouse skin. The expression of IL-33 by macrophages was induced by staphylococcal peptidoglycan (PGN) and lipoteichoic acid (LTA) via activation of toll-like receptor 2(TLR2) –mitogen-activated protein kinase (MAPK)-AKT-signal transducer and activator of transcription 3(STAT3) signaling pathway as PGN and LTA failed to induce IL-33 in Tlr2-deficient peritoneal macrophages, and MAPK,AKT, STAT3 inhibitors significantly decreased PGN- or LTA-induced IL-33. IL-33, in turn, acted on macrophages to induce microbicidal nitric oxygen (NO) release. This induction was dependent on inducible nitric oxide synthase (iNOS) activation, as treatment of macrophages with an inhibitor of iNOS, aminoguanidine, significantly decreased IL-33-induced NO release. Moreover, aminoguanidine significantly blocked the capacity of IL-33 to inhibit the growth of S. aureus, and IL-33 silencing in macrophages significantly increased the survival of S. aureus in macrophages. Furthermore, the administration of IL-33-neutralizing antibody into mouse skin decreased iNOS production but increased the survival of S. aureus in skin. These findings reveal that IL-33 can promote antimicrobial capacity of dermal macrophages, thus enhancing antimicrobial defense against skin bacterial infections. PMID:24586149

  1. Nitric oxide signals postovulatory aging-induced abortive spontaneous egg activation in rats.

    PubMed

    Premkumar, Karuppanan V; Chaube, Shail K

    2015-07-01

    Objective The aim of this study was to determine whether an increase of intracellular nitric oxide (NO) level signals postovulatory aging-induced abortive spontaneous egg activation (SEA) in rats. Methods Freshly ovulated eggs (arrested at metaphase-II stage; M-II) were cultured in vitro for 3 hours to induce postovulatory egg aging. The morphological changes, inducible nitric oxide synthase (iNOS) expression, NO, cytosolic free Ca(2+), 3',5' cyclic guanosine monophosphate (cGMP), cell division cycle 25B (Cdc25B) and Wee1 levels, specific phosphorylation (pThr-14/Tyr-15) as well as total cyclin-dependent kinases-1 (Cdk1) (PSTAIRE) levels were analyzed. Results Postovulatory aging induced generation of NO possibly through an iNOS-mediated pathway. The increase in NO level was associated with augmented cytosolic free Ca(2+) as well as cGMP levels in aged eggs. A significant increase in Wee1 level and decrease of Cdc25B level were observed in aged eggs. An accumulation of phosphorylated Cdk1 (pThr-14/Tyr-15) level was observed in aged eggs, while total Cdk1 (PSTAIR) level remained unchanged. Conclusion Our study demonstrates that generation of NO through an iNOS-mediated pathway increases cytosolic free Ca2+and cGMP levels. High levels of these signal molecules trigger the accumulation of phosphorylated Cdk1 in aged eggs. Thus, NO signals the accumulation of phosphorylated Cdk1 and induces postovulatory aging-induced abortive SEA in the rat. PMID:25780809

  2. Ethyl pyruvate protects rats from phosgene-induced pulmonary edema by inhibiting cyclooxygenase2 and inducible nitric oxide synthase expression.

    PubMed

    Chen, Hong-li; Bai, Hua; Xi, Miao-miao; Liu, Riu; Qin, Xu-jun; Liang, Xin; Zhang, Wei; Zhang, Xiao-di; Li, Wen-li; Hai, Chun-xu

    2013-01-01

    Phosgene is a poorly water-soluble gas penetrating the lower respiratory tract which can induce acute lung injury characterized by a latent phase of fatal pulmonary edema. Pulmonary edema caused by phosgene is believed to be a consequence of oxidative stress and inflammatory responses. Ethyl pyruvate (EP) has been demonstrated to have anti-inflammatory and anti-oxidative properties in vivo and in vitro. The potential therapeutic role of EP in phosgene-induced pulmonary edema has not been addressed so far. In the present study, we aim to investigate the protective effects of EP on phosgene-induced pulmonary edema and the underlying mechanisms. Rats were administered with EP (40 mg kg(-1)) and RAW264.7 cells were also incubated with it (0, 2, 5 or 10 µm) immediately after phosgene (400 ppm, 1 min) or air exposure. Wet-to-dry lung weight ratio (W:D ratio), nitric oxide (NO) and prostaglandin E(2) (PGE(2)) production, cyclooxygenase2 (COX-2) and inducible nitric oxide synthase (iNOS) expression, and mitogen-activated protein kinases activities (MAPKs) were measured. Our results showed that EP treatment attenuated phosgene-induced pulmonary edema and decreased the level of NO and PGE(2) dose-dependently. Furthermore, EP significantly reduced COX-2 expression, iNOS expression and MAPK activation induced by phosgene. Moreover, specific inhibitors of MAPKs reduced COX-2 and iNOS expression induced by phosgene. These findings suggested that EP has a protective role against phosgene-induced pulmonary edema, which is mediated in part by inhibiting MAPK activation and subsequently down-regulating COX-2 and iNOS expression as well as decreasing the production of NO and PGE(2). PMID:21818760

  3. Role of nitric oxide in adenosine-induced vasodilation in humans

    NASA Technical Reports Server (NTRS)

    Costa, F.; Biaggioni, I.; Robertson, D. (Principal Investigator)

    1998-01-01

    Vasodilation is one of the most prominent effects of adenosine and one of the first to be recognized, but its mechanism of action is not completely understood. In particular, there is conflicting information about the potential contribution of endothelial factors. The purpose of this study was to explore the role of nitric oxide in the vasodilatory effect of adenosine. Forearm blood flow responses to intrabrachial adenosine infusion (125 microg/min) were assessed with venous occlusion plethysmography during intrabrachial infusion of saline or the nitric oxide synthase inhibitor NG-monomethyl-L-arginine (L-NMMA) (12.5 mg/min). Intrabrachial infusions of acetylcholine (50 microg/min) and nitroprusside (3 microg/min) were used as a positive and negative control, respectively. These doses were chosen to produce comparable levels of vasodilation. In a separate study, a second saline infusion was administered instead of L-NMMA to rule out time-related effects. As expected, pretreatment with L-NMMA reduced acetylcholine-induced vasodilation; 50 microg/min acetylcholine increased forearm blood flow by 150+/-43% and 51+/-12% during saline and L-NMMA infusion, respectively (P<.01, n=6). In contrast, L-NMMA did not affect the increase in forearm blood flow produced by 3 microg/min nitroprusside (165+/-30% and 248+/-41% during saline and L-NMMA, respectively) or adenosine (173+/-48% and 270+/-75% during saline and L-NMMA, respectively). On the basis of our observations, we conclude that adenosine-induced vasodilation is not mediated by nitric oxide in the human forearm.

  4. Nitric Oxide Acts as a Positive Regulator to Induce Metamorphosis of the Ascidian Herdmania momus

    PubMed Central

    Ueda, Nobuo; Degnan, Sandie M.

    2013-01-01

    Marine invertebrates commonly have a biphasic life cycle in which the metamorphic transition from a pelagic larva to a benthic post-larva is mediated by the nitric oxide signalling pathway. Nitric oxide (NO) is synthesised by nitric oxide synthase (NOS), which is a client protein of the molecular chaperon heat shock protein 90 (HSP90). It is notable, then, that both NO and HSP90 have been implicated in regulating metamorphosis in marine invertebrates as diverse as urochordates, echinoderms, molluscs, annelids, and crustaceans. Specifically, the suppression of NOS activity by the application of either NOS- or HSP90-inhibiting pharmacological agents has been shown consistently to induce the initiation of metamorphosis, leading to the hypothesis that a negative regulatory role of NO is widely conserved in biphasic life cycles. Further, the induction of metamorphosis by heat-shock has been demonstrated for multiple species. Here, we investigate the regulatory role of NO in induction of metamorphosis of the solitary tropical ascidian, Herdmania momus. By coupling pharmacological treatments with analysis of HmNOS and HmHSP90 gene expression, we present compelling evidence of a positive regulatory role for NO in metamorphosis of this species, in contrast to all existing ascidian data that supports the hypothesis of NO as a conserved negative regulator of metamorphosis. The exposure of competent H. momus larvae to a NOS inhibitor or an NO donor results in an up-regulation of NOS and HSP90 genes. Heat shock of competent larvae induces metamorphosis in a temperature dependent manner, up to a thermal tolerance that approaches 35°C. Both larval/post-larval survival and the appearance of abnormal morphologies in H. momus post-larvae reflect the magnitude of up-regulation of the HSP90 gene in response to heat-shock. The demonstrated role of NO as a positive metamorphic regulator in H. momus suggests the existence of inter-specific adaptations of NO regulation in ascidian metamorphosis. PMID:24019877

  5. Myrislignan attenuates lipopolysaccharide-induced inflammation reaction in murine macrophage cells through inhibition of NF-?B signalling pathway activation.

    PubMed

    Jin, Hong; Zhu, Zheng-Guang; Yu, Peng-Jiu; Wang, Guang-Fa; Zhang, Jun-Yan; Li, Jing-Rong; Ai, Rui-Ting; Li, Zhong-Huang; Tian, Yuan-Xin; Zhang, Wei Xu Jia-Jie; Wu, Shu-Guang

    2012-09-01

    Myrislignan is a new kind of lignan isolated from Myristica fragrans Houtt. Its antiinflammatory effects have not yet been reported. In the present study, the antiinflammatory effects and the underlying mechanisms of myrislignan in lipopolysaccharide (LPS)-induced inflammation in murine RAW 264.7 macrophage cells were investigated. Myrislignan significantly inhibited LPS-induced production of nitric oxide (NO) in a dose-dependent manner. It inhibited mRNA expression and release of interleukin-6 (IL-6) and tumour necrosis factor-? (TNF-?). This compound significantly inhibited mRNA and protein expressions of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) dose-dependently in LPS-stimulated macrophage cells. Further study showed that myrislignan decreased the cytoplasmic loss of inhibitor ?B-? (I?B-?) protein and the translocation of NF-?B from cytoplasm to the nucleus. Our results suggest that myrislignan may exert its antiinflammatory effects in LPS-stimulated macrophages cells by inhibiting the NF-?B signalling pathway activation. PMID:22294521

  6. Bursopentin (BP5) protects dendritic cells from lipopolysaccharide-induced oxidative stress for immunosuppression.

    PubMed

    Qin, Tao; Yin, Yinyan; Yu, Qinghua; Yang, Qian

    2015-01-01

    Dendritic cells (DCs) play a vital role in the regulation of immune-mediated inflammatory diseases. Thus, DCs have been regarded as a major target for the development of immunomodulators. However, oxidative stress could disturb inflammatory regulation in DCs. Here, we examined the effect of bursopentine (BP5), a novel pentapeptide isolated from chicken bursa of fabricius, on the protection of DCs against oxidative stress for immunosuppression. BP5 showed potent protective effects against the lipopolysaccharide (LPS)-induced oxidative stress in DCs, including nitric oxide, reactive oxygen species and lipid peroxidation. Furthermore, BP5 elevated the level of cellular reductive status through increasing the reduced glutathione (GSH) and the GSH/GSSG ratio. Concomitant with these, the activities of several antioxidative redox enzymes, including glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD), were obviously enhanced. BP5 also suppressed submucosal DC maturation in the LPS-stimulated intestinal epithelial cells (ECs)/DCs coculture system. Finally, we found that heme oxygenase 1 (HO-1) was remarkably upregulated by BP5 in the LPS-induced DCs, and played an important role in the suppression of oxidative stress and DC maturation. These results suggested that BP5 could protect the LPS-activated DCs against oxidative stress and have potential applications in DC-related inflammatory responses. PMID:25659113

  7. Radiation-induced nitric oxide mitigates tumor hypoxia and radioresistance in a murine SCCVII tumor model

    SciTech Connect

    Nagane, Masaki, E-mail: nagane@vetmed.hokudai.ac.jp [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan)] [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan); Yasui, Hironobu, E-mail: yassan@vetmed.hokudai.ac.jp [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan)] [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan); Yamamori, Tohru, E-mail: yamamorit@vetmed.hokudai.ac.jp [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan)] [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan); Zhao, Songji, E-mail: zsi@med.hokudai.ac.jp [Department of Tracer Kinetics and Bioanalysis, Graduate School of Medicine, Hokkaido University, Sapporo (Japan)] [Department of Tracer Kinetics and Bioanalysis, Graduate School of Medicine, Hokkaido University, Sapporo (Japan); Kuge, Yuji, E-mail: kuge@med.hokudai.ac.jp [Central Institute of Isotope Science, Hokkaido University, Sapporo (Japan)] [Central Institute of Isotope Science, Hokkaido University, Sapporo (Japan); Tamaki, Nagara, E-mail: natamaki@med.hokudai.ac.jp [Department of Nuclear Medicine, Graduate School of Medicine, Hokkaido University, Sapporo (Japan)] [Department of Nuclear Medicine, Graduate School of Medicine, Hokkaido University, Sapporo (Japan); Kameya, Hiromi, E-mail: kameya@affrc.go.jp [Food Safety Division, National Food Research Institute, Tsukuba (Japan)] [Food Safety Division, National Food Research Institute, Tsukuba (Japan); Nakamura, Hideo, E-mail: naka@science-edu.org [Department of Chemistry, Hokkaido University of Education, Hakodate (Japan)] [Department of Chemistry, Hokkaido University of Education, Hakodate (Japan); Fujii, Hirotada, E-mail: hgfujii@sapmed.ac.jp [Center for Medical Education, Sapporo Medical University, Sapporo (Japan)] [Center for Medical Education, Sapporo Medical University, Sapporo (Japan); Inanami, Osamu, E-mail: inanami@vetmed.hokudai.ac.jp [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan)] [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan)

    2013-08-02

    Highlights: •IR-induced NO increased tissue perfusion and pO{sub 2}. •IR increased NO production in tumors without changes in the mRNA and protein levels of NOS isoforms. •NOS activity assay showed that IR upregulated eNOS activity in tumors. •IR-induced NO decreased tumor hypoxia and altered tumor radiosensitivity. -- Abstract: Tumor hypoxia, which occurs mainly as a result of inadequate tissue perfusion in solid tumors, is a well-known challenge for successful radiotherapy. Recent evidence suggests that ionizing radiation (IR) upregulates nitric oxide (NO) production and that IR-induced NO has the potential to increase intratumoral circulation. However, the kinetics of NO production and the responsible isoforms for NO synthase in tumors exposed to IR remain unclear. In this study, we aimed to elucidate the mechanism by which IR stimulates NO production in tumors and the effect of IR-induced NO on tumor radiosensitivity. Hoechst33342 perfusion assay and electron spin resonance oxymetry showed that IR increased tissue perfusion and pO{sub 2} in tumor tissue. Immunohistochemical analysis using two different hypoxic probes showed that IR decreased hypoxic regions in tumors; treatment with a nitric oxide synthase (NOS) inhibitor, L-NAME, abrogated the effects of IR. Moreover, IR increased endothelial NOS (eNOS) activity without affecting its mRNA or protein expression levels in SCCVII-transplanted tumors. Tumor growth delay assay showed that L-NAME decreased the anti-tumor effect of fractionated radiation (10 Gy × 2). These results suggested that IR increased eNOS activity and subsequent tissue perfusion in tumors. Increases in intratumoral circulation simultaneously decreased tumor hypoxia. As a result, IR-induced NO increased tumor radiosensitivity. Our study provides a new insight into the NO-dependent mechanism for efficient fractionated radiotherapy.

  8. Transient blood brain barrier disruption induced by oleic acid is mediated by nitric oxide.

    PubMed

    Han, Hyung Soo; Jang, Jae Hee; Park, Jae Sik; Kim, Hak Jin; Kim, Jong Kun

    2013-11-01

    The blood brain barrier (BBB) maintains cerebral microenvironmental homeostasis. Transient disruption of the BBB after brain fat embolism in clinical cases and animal models has been reported but the precise mechanism underlying this occurrence is unclear. In the present study, we investigated BBB alterations in rats treated oleic acid (OA) delivered intra-arterially. Following OA treatment, transient brain edema, extravasation of Evans blue and Fluorescein isothiocyanate (FITC)-labeled dextran, and loss of laminin in the affected brain area were observed. Activation of matrix metalloproteinase (MMP)-2, -3, and -13 was found in the cerebral vessels 2 h after OA administration. Expression of intercellular adhesion molecule (ICAM)-1 in the vessels and neutrophil infiltration into the brain tissue was also observed. Inducible nitric oxide synthase (iNOS) was expressed in the neutrophils and nitrotyrosine was produced mainly in the vessels. Inhibitor of iNOS activity suppressed the loss of laminin, leakage of FITC-labeled dextran and Evans blue, and activation of MMP-2 and -13. Protein level of aquaporin (AQ)-4 was increased after OA administration but was not affected by treatment with iNOS inhibitor. In conclusion, we suggest that nitric oxide (NO) contributes to OA-induced MMP activation, BBB disruption and the development of transient brain edema. PMID:23937199

  9. A common fungal volatile organic compound induces a nitric oxide mediated inflammatory response in Drosophila melanogaster

    PubMed Central

    Inamdar, Arati A.; Bennett, Joan W.

    2014-01-01

    Using a Drosophila model, we previously demonstrated truncated life span and neurotoxicity with exposure to 1-octen-3-ol, the volatile organic compound (VOC) responsible for much of the musty odor found in mold-contaminated indoor spaces. In this report, using biochemical and immunological assays, we show that exposure to 0.5?ppm 1-octen-3-ol induces a nitric oxide (NO) mediated inflammatory response in hemocytes, Drosophila innate immune cells. Moreover, exposed Drosophila brains show increased peroxynitrite expression. An increase in nitrite levels is observed with toluene and 1-octen-3-ol but not with 1-butanol. Pharmacological inhibitors of nitric oxide synthase (NOS) namely, L-NAME, D-NAME and minocycline, and NOS mutants show improvements of life span among 1-octen-3-ol exposed flies. Exposure to 1-octen-3-ol also induces NOS expression in larval tracheal tissues and remodels tracheal epithelial lining. These findings suggest a possible mechanistic basis for some of the reported adverse health effects attributed to mold exposure and demonstrates the utility of this in vivo Drosophila model to complement existing model systems for understanding the role of inflammation in VOC-mediated toxicity. PMID:24509902

  10. Expression of Inducible Nitric Oxide Synthase (iNOS) in Microglia of the Developing Quail Retina

    PubMed Central

    Sierra, Ana; Navascués, Julio; Cuadros, Miguel A.; Calvente, Ruth; Martín-Oliva, David; Ferrer-Martín, Rosa M.; Martín-Estebané, María; Carrasco, María-Carmen; Marín-Teva, José L.

    2014-01-01

    Inducible nitric oxide synthase (iNOS), which produce large amounts of nitric oxide (NO), is induced in macrophages and microglia in response to inflammatory mediators such as LPS and cytokines. Although iNOS is mainly expressed by microglia that become activated in different pathological and experimental situations, it was recently reported that undifferentiated amoeboid microglia can also express iNOS during normal development. The aim of this study was to investigate the pattern of iNOS expression in microglial cells during normal development and after their activation with LPS by using the quail retina as model. iNOS expression was analyzed by iNOS immunolabeling, western-blot, and RT-PCR. NO production was determined by using DAR-4M AM, a reliable fluorescent indicator of subcellular NO production by iNOS. Embryonic, postnatal, and adult in situ quail retinas were used to analyze the pattern of iNOS expression in microglial cells during normal development. iNOS expression and NO production in LPS-treated microglial cells were investigated by an in vitro approach based on organotypic cultures of E8 retinas, in which microglial cell behavior is similar to that of the in situ retina, as previously demonstrated in our laboratory. We show here that amoeboid microglia in the quail retina express iNOS during normal development. This expression is stronger in microglial cells migrating tangentially in the vitreal part of the retina and is downregulated, albeit maintained, when microglia differentiate and become ramified. LPS treatment of retina explants also induces changes in the morphology of amoeboid microglia compatible with their activation, increasing their lysosomal compartment and upregulating iNOS expression with a concomitant production of NO. Taken together, our findings demonstrate that immature microglial cells express iNOS during normal development, suggesting a certain degree of activation. Furthermore, LPS treatment induces overactivation of amoeboid microglia, resulting in a significant iNOS upregulation. PMID:25170849

  11. Nitric Oxide Is a Mediator of Antiproliferative Effects Induced by Proinflammatory Cytokines on Pancreatic Beta Cells

    PubMed Central

    Quintana-Lopez, Laura; Blandino-Rosano, Manuel; Perez-Arana, Gonzalo; Lechuga-Sancho, Alfonso; Aguilar-Diosdado, Manuel

    2013-01-01

    Nitric oxide (NO) is involved in several biological processes. In type 1 diabetes mellitus (T1DM), proinflammatory cytokines activate an inducible isoform of NOS (iNOS) in ? cells, thus increasing NO levels and inducing apoptosis. The aim of the current study is to determine the role of NO (1) in the antiproliferative effect of proinflammatory cytokines IL-1?, IFN-?, and TNF-? on cultured islet ? cells and (2) during the insulitis stage prior to diabetes onset using the Biobreeding (BB) rat strain as T1DM model. Our results indicate that NO donors exert an antiproliferative effect on ? cell obtained from cultured pancreatic islets, similar to that induced by proinflammatory cytokines. This cytokine-induced antiproliferative effect can be reversed by L-NMMA, a general NOS inhibitor, and is independent of guanylate cyclase pathway. Assays using NOS isoform specific inhibitors suggest that the NO implicated in the antiproliferative effect of proinflammatory cytokines is produced by inducible NOS, although not in an exclusive way. In BB rats, early treatment with L-NMMA improves the initial stage of insulitis. We conclude that NO is an important mediator of antiproliferative effect induced by proinflammatory cytokines on cultured ? cell and is implicated in ?-cell proliferation impairment observed early from initial stage of insulitis. PMID:23840099

  12. Hypoxia augments lipopolysaccharide-induced cytokine expression in periodontal ligament cells.

    PubMed

    Jian, Congxiang; Li, Chenjun; Ren, Yu; He, Yong; Li, Yunming; Feng, Xiaodan; Zhang, Gang; Tan, Yinghui

    2014-10-01

    Periodontitis is a chronic inflammatory disease characterized by the destruction of tooth supporting tissues. Hypoxia, the mainly changes of the plateau environment, can induce severe periodontitis by animal experiments. There is, however, very little information on hypoxia and lipopolysaccharide (LPS) induced cytokine expression in periodontal ligament (PDL) cells. In this article, we characterized hypoxia or P. gingivalis lipopolysaccharide (Pg LPS) induced tumor necrosis factor alpha (TNF-?), interleukin (IL)-1?, and IL-6 expression by human periodontal ligament (hPDL) cells. We found that hypoxia augmented Pg LPS induced TNF-?, IL-1?, and IL-6 expression in hPDL cells. We also demonstrated that nuclear factor kappa B pathway was involved in hypoxia augmenting Pg LPS induced cytokine expression in hPDL cells. Thus, our results suggest that the hypoxic environment may enhance the immune function of hPDL cells that is induced by Pg LPS. PMID:24609838

  13. Epigallocatechin gallate (EGCG) suppresses lipopolysaccharide-induced inflammatory bone resorption, and protects against alveolar bone loss in mice

    PubMed Central

    Tominari, Tsukasa; Matsumoto, Chiho; Watanabe, Kenta; Hirata, Michiko; Grundler, Florian M.W.; Miyaura, Chisato; Inada, Masaki

    2015-01-01

    Epigallocatechin gallate (EGCG), a major polyphenol in green tea, possesses antioxidant properties and regulates various cell functions. Here, we examined the function of EGCG in inflammatory bone resorption. In calvarial organ cultures, lipopolysaccharide (LPS)-induced bone resorption was clearly suppressed by EGCG. In osteoblasts, EGCG suppressed the LPS-induced expression of COX-2 and mPGES-1 mRNAs, as well as prostaglandin E2 production, and also suppressed RANKL expression, which is essential for osteoclast differentiation. LPS-induced bone resorption of mandibular alveolar bones was attenuated by EGCG in vitro, and the loss of mouse alveolar bone mass was inhibited by the catechin in vivo.

  14. Nitric oxide protects the heart from ischemia-induced apoptosis and mitochondrial damage via protein kinase G mediated blockage of permeability transition and cytochrome c release

    E-print Network

    Borutaite, Vilmante; Morkuniene, Ramune; Arandarcikaite, Odeta; Jekabsone, Aiste; Barauskaite, Jurgita; Brown, Guy C

    2009-08-11

    Abstract Background Heart ischemia can rapidly induce apoptosis and mitochondrial dysfunction via mitochondrial permeability transition-induced cytochrome c release. We tested whether nitric oxide (NO) can block this damage in isolated rat heart...

  15. Inhibition of MAP kinase/NF-kB mediated signaling and attenuation of lipopolysaccharide induced severe sepsis by cerium oxide nanoparticles.

    PubMed

    Selvaraj, Vellaisamy; Nepal, Niraj; Rogers, Steven; Manne, Nandini D P K; Arvapalli, Ravikumar; Rice, Kevin M; Asano, Shinichi; Fankhanel, Erin; Ma, Jane J; Shokuhfar, Tolou; Maheshwari, Mani; Blough, Eric R

    2015-08-01

    Sepsis is a life threatening disease that is associated with high mortality. Existing treatments have failed to improve survivability in septic patients. The purpose of this present study is to evaluate whether cerium oxide nanoparticles (CeO2NPs) can prevent lipopolysaccharide (LPS) induced severe sepsis mortality by preventing hepatic dysfunction in male Sprague Dawley rats. Administration of a single dose (0.5 mg/kg) of CeO2NPs intravenously to septic rats significantly improved survival rates and functioned to restore body temperature, respiratory rate and blood pressure towards baseline. Treatment-induced increases in animal survivability were associated with decreased hepatic damage along with reductions in serum cytokines/chemokines, and diminished inflammatory related signaling. Kupffer cells and macrophage cells exposed to CeO2NPs exhibited decreases in LPS-induced cytokine release (TNF-?, IL-1?, IL-6, HMGB1) which were associated with diminished cellular ROS, reduced levels of nitric oxide synthase (iNOS), cyclooxygenase 2 (COX-2), and decreased nuclear factor-kappa light chain enhancer of activated B cells (NF-kB) transcriptional activity. The findings of this study indicate that CeO2NPs may be useful as a therapeutic agent for sepsis. PMID:25968464

  16. Renal angiotensin-converting enzyme is essential for the hypertension induced by nitric oxide synthesis inhibition.

    PubMed

    Giani, Jorge F; Janjulia, Tea; Kamat, Nikhil; Seth, Dale M; Blackwell, Wendell-Lamar B; Shah, Kandarp H; Shen, Xiao Z; Fuchs, Sebastien; Delpire, Eric; Toblli, Jorge E; Bernstein, Kenneth E; McDonough, Alicia A; Gonzalez-Villalobos, Romer A

    2014-12-01

    The kidney is an important source of angiotensin-converting enzyme (ACE) in many species, including humans. However, the specific effects of local ACE on renal function and, by extension, BP control are not completely understood. We previously showed that mice lacking renal ACE, are resistant to the hypertension induced by angiotensin II infusion. Here, we examined the responses of these mice to the low-systemic angiotensin II hypertensive model of nitric oxide synthesis inhibition with L-NAME. In contrast to wild-type mice, mice without renal ACE did not develop hypertension, had lower renal angiotensin II levels, and enhanced natriuresis in response to L-NAME. During L-NAME treatment, the absence of renal ACE was associated with blunted GFR responses; greater reductions in abundance of proximal tubule Na(+)/H(+) exchanger 3, Na(+)/Pi co-transporter 2, phosphorylated Na(+)/K(+)/Cl(-) cotransporter, and phosphorylated Na(+)/Cl(-) cotransporter; and greater reductions in abundance and processing of the ? isoform of the epithelial Na(+) channel. In summary, the presence of ACE in renal tissue facilitates angiotensin II accumulation, GFR reductions, and changes in the expression levels and post-translational modification of sodium transporters that are obligatory for sodium retention and hypertension in response to nitric oxide synthesis inhibition. PMID:25012170

  17. Time-course of neuropathic pain in mice deficient in neuronal or inducible nitric oxide synthase.

    PubMed

    Keilhoff, Gerburg; Schröder, Helmut; Peters, Brigitte; Becker, Axel

    2013-12-01

    Nitric oxide which is synthesised by nitric oxide synthase (NOS) is involved in processes related to regeneration after nerve injury and neuropathic pain. Here we investigated functional aspects of the nociceptive system. For that purpose, the chronic constriction injury (CCI) model induced by loose ligation of the sciatic nerve was employed in C57Bl/6J wild-type (WT), nNOS and iNOS knock-out (-/-) mice. Their thermal and mechanical pain thresholds were then measured over a period of six weeks. In addition, (3)H-DAMGO, (3)H-CP 55.940, and (3)H-l-glutamate binding, and neuronal (NeuN-immunostained) and astroglial (GFAP-immunostained) cell composition were studied. There were no significant differences in cell composition between the three strains used. Significant differences between CCI and sham-operated animals were found in nNOS-/- after day 6, in WT mice after day 10, and in iNOS-/- after day 17 post surgery. The mechanical pain threshold was normalised after day 45 post surgery in WT mice only. There were no changes in DAMGO and glutamate binding. However, we found significant differences in CP 55.940 binding in the spinal cord. It was concluded that NOS-cannabinoid interaction contributes to differences in nociceptive behaviour. PMID:24008126

  18. Inducible nitric oxide synthase expression in gastric adenocarcinoma: impact on lymphangiogenesis and lymphatic metastasis

    PubMed Central

    2013-01-01

    Background Lymphatic metastasis is the most important parameter in the spread of gastric carcinomas. Nitric oxide (NO) is a signaling molecule that plays an important role in inflammation and carcinogenesis. In this study, the possible link between inducible nitric oxide synthase (iNOS) expression with lymphangiogenesis and the clinicopathological parameters of gastric carcinomas was investigated. Methods In this study, iNOS expression and D2-40 (lymphatic endothelium-specific marker monoclonal antibody) reactivity were examined immunohistochemically in 41 gastric adenocarcinoma and 20 non-neoplastic gastric tissues. iNOS expression was scored semiquantitatively in the tumor parenchyma and stroma. D2-40-positive lymphatic vessels were used in the determination of lymphatic invasion and intratumoral and peritumoral lymphatic vascular density. Results iNOS expression was higher in gastric carcinoma tissue compared with non-neoplastic tissue. Particularly, iNOS expression in tumor cells was found to be closely related to lymphangiogenesis and lymphatic metastasis. The density of lymphatic invasion as well as intratumoral and peritumoral lymphatic vascular density were positively correlated with lymph node metastasis. Conclusions Our results suggest that iNOS-mediated NO formation plays an important role in gastric carcinogenesis, tumor lymphangiogenesis, and the development of lymphatic metastases. Inhibition of the NO pathway may be an alternative treatment of gastric carcinomas. Virtual slides The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1713572940104388. PMID:24044375

  19. Expression of inducible nitric oxide synthase and its involvement in pulmonary granulomatous inflammation in rats.

    PubMed Central

    Setoguchi, K.; Takeya, M.; Akaike, T.; Suga, M.; Hattori, R.; Maeda, H.; Ando, M.; Takahashi, K.

    1996-01-01

    Two types of pulmonary granulomatosis were produced in rats by intratracheal instillation of zymosan or silica. In both models, immunostaining with anti-rat monoclonal antibody for inducible nitric oxide synthase (iNOS), ANOS11, showed that the intensity of iNOS immunoreactivity in the inflammatory lesions peaked at 3 days and declined thereafter. Immunohistochemical double staining and in situ hybridization demonstrated the expression of iNOS in neutrophils, monocyte-derived macrophages, and bronchiolar epithelial cells in the pulmonary lesions. Electron spin resonance spectroscopy revealed the production of an excessive amount of nitric oxide (NO) in the pulmonary lesions. Immunostaining with a polyclonal antibody against nitrotyrosine indicated the formation of nitrotyrosine residues in the granulomatous lesions, particularly in the periphery of the lesions, providing indirect evidence for the generation of peroxynitrite anion in the zymosan- or silica-instilled lungs. Administration of N omega-nitro-L-arginine methyl ester or S-methylisothiourea sulfate, which significantly suppressed NO production, resulted in marked reduction of monocyte/macrophage infiltration as well as in inhibition of induction of monocyte chemoattractant protein-1 in the lesions. These data indicate that NO and its more reactive product peroxynitrite anion may be important mediators of granuloma formation in the lung. Images Figure 1 Figure 2 Figure 4 Figure 8 Figure 9 PMID:8952535

  20. Inducible nitric oxide synthase in pulmonary alveolar macrophages from patients with tuberculosis

    PubMed Central

    1996-01-01

    The high-output pathway of nitric oxide production helps protect mice from infection by several pathogens, including Mycobacterium tuberculosis. However, based on studies of cells cultured from blood, it is controversial whether human mononuclear phagocytes can express the corresponding inducible nitric oxide synthase (iNOS;NOS2). The present study examined alveolar macrophages fixed directly after bronchopulmonary lavage. An average of 65% of the macrophages from 11 of 11 patients with untreated, culture-positive pulmonary tuberculosis reacted with an antibody documented herein to be monospecific for human NOS2. In contrast, a mean of 10% of bronchoalveolar lavage cells were positive from each of five clinically normal subjects. Tuberculosis patients' macrophages displayed diaphorase activity in the same proportion that they stained for NOS2, under assay conditions wherein the diaphorase reaction was strictly dependent on NOS2 expression. Bronchoalveolar lavage specimens also contained NOS2 mRNA. Thus, macrophages in the lungs of people with clinically active Mycobacterium tuberculosis infection often express catalytically competent NOS2. PMID:8642338

  1. Pharmacological profile of FR260330, a novel orally active inducible nitric oxide synthase inhibitor.

    PubMed

    Chida, Noboru; Hirasawa, Yoshimi; Ohkawa, Takehiko; Ishii, Yoshinori; Sudo, Yuji; Tamura, Kouichi; Mutoh, Seitaro

    2005-02-10

    In this study, we examined effects of a newly synthesized chemical compound, FR260330, (2E)-3-(4-chlorophenyl)-N-[(1S)-2-oxo-2-{[2-oxo-2-(4-{[6-(trifluoromethyl)-4-pyrimidinyl]oxy}-1-piperidinyl)ethyl]amino}-1-(2-pyridinylmethyl)ethyl]acrylamide on nitric oxide (NO) production in rat splenocytes and human colon cancer cell line, DLD-1 cells. FR260330 inhibited NOx production dose dependently in both cells. In lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma) treated murine macrophage cell line, RAW264.7, Western blot analysis with gel filtration chromatography revealed FR260330 might prevent dimerization of inducible nitric oxide synthase (iNOS), but had no effect on the expression of iNOS protein. Furthermore, oral administration of FR260330 reduced NOx production dose dependently in plasma from rats exposed to LPS (IC50=1.6 mg/kg). Meanwhile, higher dose (100 mg/kg) of oral administration of FR260330 did not change mean arterial blood pressure in rats. These results suggest that FR260330 might be a useful therapeutical approach to various inflammatory diseases, in which superoxide or peroxynitrite formed from iNOS-derived NO are involved. PMID:15713431

  2. Expression of the inducible nitric oxide synthase isoform in chorionic villi in the early spontaneous abortion.

    PubMed

    Xia, G; Sun, Y

    2000-01-01

    To investigate the relationship between inducible nitric oxide synthase (iNOS) and the early spontaneous abortion., in situ hybridization and immunohistochemistry were used to detect the expression of iNOS in trophoblasts in the early pregnancy with and without spontaneous abortion (group I and group II). By light microscopy and computer color magic image analysis system (CMIAS), light density (D) and the positive cell number per statistic square (N/S) in situ hybridization were used to analyze the positive cell index, while total positive cells (N) and the positive unit (Pu) were used in immunohistochemistry. By in situ hybridization, D and N/S in trophoblasts were 0.35 +/- 0.028, 0.07 +/- 0.011 respectively in group I and 0.18 +/- 0.016, 0.015 +/- 0.003 in group II. In terms of immunohistochemical staining, N and Pu were 0.058 +/- 0.007, 11.94 +/- 2.01 in group I and 0.013 +/- 0.009, 1.08 +/- 0.35 in group II in trophoblasts. Significant differences existed between two groups. It is concluded that the higher nitric oxide produced by the higher expression of iNOS in trophoblasts might play an important role in the early spontaneous abortion. PMID:12840930

  3. The role of nitric oxide in diabetes-induced changes of morphine tolerance in rats.

    PubMed

    Joharchi, Khojasteh; Jorjani, Masoumeh

    2007-09-10

    Several neuroendocrine complications including diabetes change the morphine antinociception and the development of tolerance to the drug. Morphine antinociception was reduced significantly in morphine tolerant diabetic rats compared to the non-diabetic animals. The exact mechanism of this effect is not known. This study was performed to determine the role of nitric oxide (NO) on morphine tolerance in diabetic state. Nociceptive responses in alloxan-induced diabetic morphine tolerated rats were measured by the hot-plate test. The urinary nitric oxide level was measured spectrophotometrically with Griess reagent. For the conversion of nitrate to nitrite, vanadium chloride was used. The results showed that experimental diabetes increased morphine analgesia. Conversely, degree of tolerance to morphine was diminished in diabetic state. The urinary nitrite content in diabetic morphine tolerated rats was higher than non-diabetic groups. L-arginine significantly increased the NO production in diabetic morphine tolerated animals, whereas aminoguanidine decreased it. Appropriately, L-arginine increased the latency time of reaction to noxious stimuli in diabetic compared to non-diabetic rats. L-arginine-treated animals also showed more tolerance to morphine analgesia. As expected, aminoguanidine deducted the level of morphine tolerance in diabetic animals. It is suggested that NO has a modulatory role in the effects of diabetes on morphine analgesia and tolerance. PMID:17599829

  4. Inducible nitric oxide synthase inhibits oxygen consumption in collateral-dependent myocardium.

    PubMed

    Chen, Yingjie; Zhang, Ping; Li, Jingxin; Xu, Xin; Bache, Robert J

    2014-02-01

    Following coronary artery occlusion growth of collateral vessels can provide an effective blood supply to the dependent myocardium. The ischemia, which results in growth of collateral vessels, recruits an inflammatory response with expression of cytokines and growth factors, upregulation of endothelial nitric oxide (NO) synthase (eNOS) in vascular endothelial cells, and expression of inducible nitric oxide synthase (iNOS) in both vessels and cardiac myocytes. Because NO is a potent collateral vessel dilator, this study examined whether NO derived from iNOS or constitutive NOS regulates myocardial blood flow (MBF) in the collateral region. Nonselective NOS inhibition with N(G)-nitro-l-arginine (LNA) caused vasoconstriction with a significant decrease in MBF to the collateral region during exercise. In contrast, the highly selective iNOS inhibitor 1400W caused a 21 ± 5% increase of MBF in the collateral region. This increase in MBF following selective iNOS blockade was proportionate to an increase in myocardial O2 consumption (MVo2). The results suggest that NO produced by iNOS inhibits MVo2 in the collateralized region, so that the increase in MBF following iNOS blockade was the result of metabolic vasodilation secondary to an increase in MVo2. Thus the coordinated expression of iNOS to restrain MVo2 and eNOS to maintain collateral vasodilation act to optimize the O2 supply-demand relationship and protect the collateralized myocardium from ischemia. PMID:24322607

  5. Entamoeba histolytica modulates the nitric oxide synthase gene and nitric oxide production by macrophages for cytotoxicity against amoebae and tumour cells.

    PubMed Central

    Wang, W; Keller, K; Chadee, K

    1994-01-01

    Nitric oxide (NO) is the major cytotoxic molecule produced by activated macrophages for cytotoxicity against Entamoeba histolytica trophozoites. In the present study, we determined whether E. histolytica infection and soluble amoebic proteins affected macrophage cytotoxicity against amoebae and tumour cells by modulating the inducible NO synthase gene (iNOS) and NO (measured as nitrite, NO2-) and tumour necrosis factor-alpha (TNF-alpha) production. Amoebic liver abscess-derived macrophages [days 10, 20, 30 post-infection (p.i.)] stimulated with interferon-gamma (IFN-gamma) and lipopolysaccharide (LPS) showed increased cytotoxicity against L929 cells (TNF-alpha-sensitive), but were refractory for killing amoebae and P815 cells (both NO-sensitive), concomitant with low NO2- production (< 4 microM/10(6) cells). In contrast, peritoneal and spleen macrophages at 10 and 20 days p.i. activated with IFN-gamma and LPS demonstrated increased killing of amoebae, and L929 and P815 cells concomitant with high NO2- production (> 12 microM/10(6) cells). Pretreatment of mouse bone marrow-derived macrophages with amoebic proteins suppressed IFN-gamma and LPS-induced amoebicidal (33%) and tumoricidal (44-49%) activities, with a corresponding decrease in TNF-alpha (56%) and NO (41%) production as well as TNF-alpha (41%) and iNOS (27%) mRNA by Northern blot analyses as compared to untreated activated controls. Inhibition of prostaglandin E2 (PGE2) biosynthesis in abscess and naive macrophages pretreated with amoebic proteins augmented IFN-gamma- and LPS-induced killing of L929 cells and TNF-alpha production, but failed to increase killing of P815 cells and amoebae as well as iNOS mRNA levels or NO production. These results suggest that E. histolytica selectively induces dysfunction of macrophage cytotoxicity by modulating iNOS mRNA expression and NO production independent from TNF-alpha and PGE2 allowing the parasites to survive within the host by impairing host immune responses. Images Figure 4 PMID:7533135

  6. Central role for type I interferons and Tyk2 in lipopolysaccharide-induced endotoxin shock

    Microsoft Academic Search

    Marina Karaghiosoff; Ralf Steinborn; Pavel Kovarik; Gernot Kriegshäuser; Manuela Baccarini; Birgit Donabauer; Ursula Reichart; Thomas Kolbe; Christian Bogdan; Tomas Leanderson; David Levy; Thomas Decker; Mathias Müller

    2003-01-01

    Toll-like receptor-4 activation by lipopolysaccharide (LPS) induces the expression of interferon-? (IFN-?) in a MyD88-independent manner. Here we report that mice devoid of the JAK protein tyrosine kinase family member, Tyk2, were resistant to shock induced by high doses of LPS. Basal and LPS-induced expression of IFN-? and IFN-?4 mRNA in Tyk2-null macrophages were diminished. However, Tyk2-null mice showed normal

  7. Increased exhaled nitric oxide in active pulmonary tuberculosis due to inducible NO synthase upregulation in alveolar macrophages

    Microsoft Academic Search

    C.-H. Wang; C.-Y. Liu; H.-C. Lin; C.-T. Yu; K. F. Chung; H.-P. Kuo

    1998-01-01

    Nitric oxide (NO) plays an important role in resistance to Mycobacte- rium tuberculosis infection. Our aim was to determine whether inducible NO synthase (iNOS) expression and generation of reactive nitrogen intermediates (RNI) by alveo- lar macrophages (AM) are increased in patients infected with M. tuberculosis. NO levels in the exhaled air of 19 active pulmonary tuberculosis (TB) and 14 con-

  8. Nitric oxide is involved in phosphorus deficiency-induced cluster root development and citrate exudation in white lupin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    White lupin (Lupinus albus) forms specialized cluster roots characterized by exudation of organic anions under phosphorus (P) deficiency. Here, we evaluated the role of nitric oxide (NO) in P deficiency-induced cluster-root formation and citrate exudation in white lupin. Plants were treated with NO ...

  9. Expression of Inducible Nitric Oxide Synthase in Bovine Corneal Endothelial Cells and Keratocytes In Vitro After Lipopolysaccharide and Cytokines Stimulation

    Microsoft Academic Search

    Pablo Dighiero; Francine Behar-Cohen; Yves Courtois; Olivier Goureau

    1997-01-01

    Purpose. To determine whether bovine corneal endothelial (BCE) cells and keratocytes express the inducible form of nitric oxide synthase (NOS) after exposure to cytokines and lipopolysac- charide (LPS), and to study the regulation of NOS by growth factors. Methods. Cultures of bovine corneal endothelial cells and keratocytes were exposed to increas- ing concentrations of LPS, interferon-y (IFN-y), and tumor necrosis

  10. The effect of glutamine on inducible nitric oxide synthase gene expression in intestinal ischemia-reperfusion injury

    Microsoft Academic Search

    Gil Joon Suh; Yeo Kyu Youn; Hyoung Gon Song; Joong Eui Rhee; Sung Eun Jung

    2003-01-01

    The aim of this study was to investigate the effect of glutamine on inducible nitric oxide synthase (iNOS) gene expression in the gut mucosa during intestinal ischemia-reperfusion (IR) injury. After randomly receiving chow alone or glutamine mixed chow for 1 week, 40 rats underwent 30 min of intestinal ischemia by clamping the superior mesenteric artery followed by 4 or 8

  11. Vasoconstriction Caused by Cocaine is Enhanced by Sodium Salicylate: Is Inducible Nitric Oxide Synthase mRNA Related?

    Microsoft Academic Search

    Mary Irene Mendoza-Baumgart; Marco Pravetoni; Sheldon B Sparber

    2004-01-01

    We have previously found that sodium salicylate (NaSal), injected into chicken eggs at nontoxic doses used for quantifying hydroxyl free radicals in hearts and brains of embryos, caused or exacerbated hemorrhages and dramatically reduced hatchability when combined with cocaine (Coc). It has also been reported that inducible nitric oxide synthase (iNOS) gene expression is altered in brain in response to

  12. Contribution of radiation-induced, nitric oxide-mediated bystander effect to radiation-induced adaptive response.

    NASA Astrophysics Data System (ADS)

    Matsumoto, H.; Ohnishi, T.

    There has been a recent upsurge of interest in radiation-induced adaptive response and bystander effect which are specific modes in stress response to low-dose low-dose rate radiation Recently we found that the accumulation of inducible nitric oxide NO synthase iNOS in wt p53 cells was induced by chronic irradiation with gamma rays followed by acute irradiation with X-rays but not by each one resulting in an increase in nitrite concentrations of medium It is suggested that the accumulation of iNOS may be due to the depression of acute irradiation-induced p53 functions by pre-chronic irradiation In addition we found that the radiosensitivity of wt p53 cells against acute irradiation with X-rays was reduced after chronic irradiation with gamma rays This reduction of radiosensitivity of wt p53 cells was nearly completely suppressed by the addition of NO scavenger carboxy-PTIO to the medium This reduction of radiosensitivity of wt p53 cells is just radiation-induced adaptive response suggesting that NO-mediated bystander effect may considerably contribute to adaptive response induced by radiation

  13. Regulation of the inducible nitric oxide synthase and sodium pump in type 1 diabetes.

    PubMed

    Zakula, Zorica; Koricanac, Goran; Putnikovic, Biljana; Markovic, Ljiljana; Isenovic, Esma R

    2007-01-01

    Insulin-like growth factor-1 (IGF-1) is a hormone and growth factor closely related to insulin. The autocrine/paracrine actions of IGF-1 involve activation of inducible nitric oxide synthase (iNOS) and the Na(+), K(+)-ATPase sodium pump in cardiovascular tissues. Data from literature indicate that iNOS is expressed in vascular smooth muscle cells (VSMC) and that IGF-1-induced release of NO is both rapid and delayed. We hypothesize that impaired IGF-1-induced sodium pump activity/expression in rats with type 1 diabetes is related to activation of phosphatidylinositol 3 kinase (PI3K)/cytosolic phospholipase 2 (cPLA(2))/protein kinase B (Akt) signaling, and that IGF-1 prevents acute and chronic dysfunction of iNOS and sodium pump activity in a chemically induced model of type 1 diabetes, the streptozotocin-treated rat heart (STZ). Understanding how iNOS and sodium pump activity are regulated by IGF-1 activation of the PI3K/cPLA(2)/Akt cascade should provide novel and fundamental knowledge regarding the regulatory actions of IGF-1 in promoting vasodilation. Since insulin resistance is currently a major focus of research, the use of IGF-1 to improve insulin resistance and glucose metabolism has opened a new arena for treatment of comorbid conditions. Future investigations should now focus on mechanisms of action of IGF-1 and its clinical applicability. PMID:17289286

  14. Nitric oxide is a mediator of tachykinin NK3 receptor-induced relaxation in rat mesenteric artery.

    PubMed Central

    Mizuta, A.; Takano, Y.; Honda, K.; Saito, R.; Matsumoto, T.; Kamiya, H.

    1995-01-01

    1. The mechanism of vasodilatation induced by tachykinin peptides was studied in isolated mesenteric arteries of rats. 2. Senktide, a selective NK3 agonist, elicited potent endothelium-dependent relaxation of arteries precontracted with phenylephrine (10(-5) M), but an NK1 agonist did not. 3. A non-peptide NK3 antagonist, SR 142801, inhibited senktide-induced relaxation. However, a non-peptide NK1 antagonist, CP-96,345, and a peptide-based NK2 antagonist, L-659,877, had no effect on senktide-induced relaxation. 4. N omega-nitro-L-arginine (L-NOARG), a nitric oxide synthesis inhibitor, markedly attenuated the relaxant response to senktide. 5. These results suggest that the endothelium of rat mesenteric arteries possesses tachykinin NK3 receptors, and that NK3 agonist-induced vasodilatation is mediated by release of nitric oxide (NO) from the endothelium. PMID:8680725

  15. Role of eicosanoids, nitric oxide, and afferent neurons in antacid induced protection in the rat stomach.

    PubMed Central

    Lambrecht, N; Trautmann, M; Korolkiewicz, R; Liszkay, M; Peskar, B M

    1993-01-01

    The mechanism underlying the mucosal protective effect of antacids is still unclear. This study shows that in rats the aluminum containing antacid, hydrotalcit, induces dose dependent protection against gastric mucosal damage caused by ethanol or indomethacin which is considerably enhanced by acidification. Hydrotalcit did not increase gastric mucosal formation or the intraluminal release of prostaglandins, and did not prevent the increase in mucosal leukotriene C4 formation in response to ethanol. Pretreatment with indomethacin did not attenuate the protective effect of unmodified or acidified hydrotalcit. Furthermore, hydrotalcit significantly reduced the gastric damage caused by indomethacin even when it was administered up to 2 hours after the ulcerogen. In indomethacin treated rats, simultaneous administration of hydrotalcit did not affect the concentrations of indomethacin in serum or inflammatory exudates nor did it attenuate the inhibition of prostaglandin release into the exudates. In hydrotalcit treated rats there was no attenuation of the increase in sulphidopeptide leukotriene release or decrease in leukocyte influx into inflammatory exudates elicited by indomethacin administration. Functional ablation of afferent neurons and inhibition of endogenous nitric oxide partially antagonised the protective effect of unmodified, but not of acidified, hydrotalcit. It is concluded that (i) the protective effect of unmodified and acidified hydrotalcit is independent of the eicosanoid system; (ii) protection against indomethacin induced gastric lesions does not require treatment before dosing of the ulcerogen and does not interfere with absorption and anti-inflammatory actions of indomethacin; (iii) endogenous nitric oxide and afferent neurons contribute partly to the effect of unmodified, but not of acidified, hydrotalcit suggesting that different mechanisms mediate their mucosal protective activity. PMID:8472979

  16. Role of eicosanoids, nitric oxide, and afferent neurons in antacid induced protection in the rat stomach.

    PubMed

    Lambrecht, N; Trautmann, M; Korolkiewicz, R; Liszkay, M; Peskar, B M

    1993-03-01

    The mechanism underlying the mucosal protective effect of antacids is still unclear. This study shows that in rats the aluminum containing antacid, hydrotalcit, induces dose dependent protection against gastric mucosal damage caused by ethanol or indomethacin which is considerably enhanced by acidification. Hydrotalcit did not increase gastric mucosal formation or the intraluminal release of prostaglandins, and did not prevent the increase in mucosal leukotriene C4 formation in response to ethanol. Pretreatment with indomethacin did not attenuate the protective effect of unmodified or acidified hydrotalcit. Furthermore, hydrotalcit significantly reduced the gastric damage caused by indomethacin even when it was administered up to 2 hours after the ulcerogen. In indomethacin treated rats, simultaneous administration of hydrotalcit did not affect the concentrations of indomethacin in serum or inflammatory exudates nor did it attenuate the inhibition of prostaglandin release into the exudates. In hydrotalcit treated rats there was no attenuation of the increase in sulphidopeptide leukotriene release or decrease in leukocyte influx into inflammatory exudates elicited by indomethacin administration. Functional ablation of afferent neurons and inhibition of endogenous nitric oxide partially antagonised the protective effect of unmodified, but not of acidified, hydrotalcit. It is concluded that (i) the protective effect of unmodified and acidified hydrotalcit is independent of the eicosanoid system; (ii) protection against indomethacin induced gastric lesions does not require treatment before dosing of the ulcerogen and does not interfere with absorption and anti-inflammatory actions of indomethacin; (iii) endogenous nitric oxide and afferent neurons contribute partly to the effect of unmodified, but not of acidified, hydrotalcit suggesting that different mechanisms mediate their mucosal protective activity. PMID:8472979

  17. Tissue expression of inducible nitric oxide synthase is closely associated with resistance to Leishmania major

    PubMed Central

    1994-01-01

    Previous studies with inhibitors of inducible nitric oxide synthase (iNOS) suggested that high-output production of nitric oxide (NO) is an important antimicrobial effector pathway in vitro and in vivo. Here, we investigated the tissue expression of iNOS in mice after infection with Leishmania major. Immunohistochemical staining with an iNOS-specific antiserum revealed that in the cutaneous lesion and draining lymph nodes (LN) of clinically resistant mice (C57BL/6), iNOS protein is found earlier during infection and in significantly higher amounts than in the nonhealing BALB/c strain. Similar differences were seen on the mRNA level as quantitated by competitive polymerase chain reaction. Anti-CD4 treatment of BALB/c mice not only induced resistance to disease, but also restored the expression of iNOS in the tissue. In situ, few or no parasites were found in those regions of the skin lesion and the draining LN which were highly positive for iNOS. By double labeling experiments, macrophages were identified as iNOS expressing cells in vivo. In the lesions of BALB/c mice, cells staining positively for transforming growth factor beta (TGF-beta), a potent inhibitor of iNOS in vitro, were strikingly more prominent than in C57BL/6, whereas no such difference was found for interleukin 4 or interferon gamma (IFN-gamma). In vitro, production of NO was approximately threefold higher in C57BL/6 than in BALB/c macrophages after stimulation with IFN-gamma. We conclude that the pronounced expression of iNOS in resistant mice is an important mechanism for the elimination of Leishmania in vivo. The relative lack of iNOS in susceptible mice might be a consequence of macrophage deactivation by TGF-beta and reduced responsiveness to IFN-gamma. PMID:7520472

  18. Nitric Oxide Regulates Cell Sensitivity to Cisplatin-Induced Apoptosis through S-Nitrosylation and Inhibition of Bcl2 Ubiquitination

    Microsoft Academic Search

    Ubonthip Nimmannit; Christian Stehlik; Liying Wang; Bing-Hua Jiang; Boonsri Ongpipatanakul; Yon Rojanasakul

    2006-01-01

    Cisplatin is a potent cytotoxic agent commonly used for the treatment of solid tumors. However, tumor cell-acquired resistance to cisplatin-induced apoptosis is a major limitation for efficient therapy, as frequently observed in human lung cancer. Nitric oxide (NO) is a key regulator of apoptosis, but its role in cisplatin-induced cell death and the underlying mechanism are largely unknown. Previous studies

  19. Differential Interleukin8 and Nitric Oxide Production in Epithelial Cells Induced by Mucosally Invasive and Noninvasive Trypanosoma cruzi Trypomastigotes

    Microsoft Academic Search

    C. S. Eickhoff; L. Eckmann; D. F. Hoft

    2003-01-01

    Trypanosoma cruzi metacyclic trypomastigotes (MT), but not blood form trypomastigotes (BFT), are highly mucosally infective. We investigated the abilities of MT and BFT to induce inflammation and\\/or intracellular killing activity within mucosal epithelia. BFT, but not MT, induced marked increases in interleukin-8, GRO-, MCP-1, and nitric oxide production in HeLa and AGS cells, despite similar infectivities. MT may avoid induction

  20. Peroxisome Proliferator-Activated Receptor-g Ligands Reduce Neuronal Inducible Nitric Oxide Synthase Expression and Cell Death In Vivo

    Microsoft Academic Search

    Michael T. Heneka; Thomas Klockgether; Douglas L. Feinstein

    2000-01-01

    Expression of the inducible form of nitric oxide synthase (iNOS) in brain may contribute to neurotoxicity in Alzheimer's disease (AD). Expression of iNOS can be induced in cerebellar granule cells (CGCs) in vivo as well as in vitro, allowing these cells to be used to study regulation of neuronal iNOS expression. We report here that microinjection of bacterial lipopolysaccharide and

  1. 3,4-Dihydroxyphenylacetic acid (DOPAC) modulates the toxicity induced by nitric oxide in PC12 cells via mitochondrial dysfunctioning

    Microsoft Academic Search

    Carla Nunes; Leonor Almeida; João Laranjinha

    2008-01-01

    It has been postulated that dihydroxyphenylacetic acid (DOPAC), a major dopamine metabolite, and nitric oxide (NO) induce mitochondrial dysfunction in a synergistic manner. We examined the combined effects of NO and DOPAC on PC-12 cells in terms of cell viability, nuclear morphology, mitochondrial parameters and cell death mechanisms. The apoptotic cell death induced by the NO-donor, S-nitroso-N-acetylpenicillamine (SNAP), was differently

  2. Nitric oxide induces airway smooth muscle cell relaxation by decreasing the frequency of agonist-induced Ca2+ oscillations

    PubMed Central

    Perez-Zoghbi, Jose F.; Bai, Yan

    2010-01-01

    Nitric oxide (NO) induces airway smooth muscle cell (SMC) relaxation, but the underlying mechanism is not well understood. Consequently, we investigated the effects of NO on airway SMC contraction, Ca2+ signaling, and Ca2+ sensitivity in mouse lung slices with phase-contrast and confocal microscopy. Airways that were contracted in response to the agonist 5-hydroxytryptamine (5-HT) transiently relaxed in response to the NO donor, NOC-5. This NO-induced relaxation was enhanced by zaprinast or vardenafil, two selective inhibitors of cGMP-specific phosphodiesterase-5, but blocked by ODQ, an inhibitor of soluble guanylyl cyclase, and by Rp-8-pCPT-cGMPS, an inhibitor of protein kinase G (PKG). Simultaneous measurements of airway caliber and SMC [Ca2+]i revealed that airway contraction induced by 5-HT correlated with the occurrence of Ca2+ oscillations in the airway SMCs. Airway relaxation induced by NOC-5 was accompanied by a decrease in the frequency of these Ca2+ oscillations. The cGMP analogues and selective PKG activators 8Br-cGMP and 8pCPT-cGMP also induced airway relaxation and decreased the frequency of the Ca2+ oscillations. NOC-5 inhibited the increase of [Ca2+]i and contraction induced by the photolytic release of inositol 1,4,5-trisphosphate (IP3) in airway SMCs. The effect of NO on the Ca2+ sensitivity of the airway SMCs was examined in lung slices permeabilized to Ca2+ by treatment with caffeine and ryanodine. Neither NOC-5 nor 8pCPT-cGMP induced relaxation in agonist-contracted Ca2+-permeabilized airways. Consequently, we conclude that NO, acting via the cGMP–PKG pathway, induced airway SMC relaxation by predominately inhibiting the release of Ca2+ via the IP3 receptor to decrease the frequency of agonist-induced Ca2+ oscillations. PMID:20176853

  3. Effects of L-canavanine, an inhibitor of inducible nitric oxide synthase, on endotoxin mediated shock in rats.

    PubMed

    Fatehi-Hassanabad, Z; Burns, H; Aughey, E A; Paul, A; Plevin, R; Parratt, J R; Furman, B L

    1996-09-01

    The effects of L-canavanine, an inhibitor of nitric oxide synthase, on endotoxin-induced shock was investigated in the pentobarbitone anesthetized rat. Endotoxin infusion (2.5 mg kg-1 h-1 over 6 h) produced progressive and marked hypotension and hypoglycemia. Electron microscopy showed marked changes in the kidney, comprising severe endothelial cell disruption and the accumulation of platelets in the blood vessels. In the lung, there was marked accumulation of polymorphonuclear leukocytes in small blood vessels and endothelial disruption. Treatment with L-canavanine (10 mg kg-1 by bolus injection each hour starting 70 min after endotoxin or saline infusion) significantly reduced endotoxin-induced hypotension, without any effect on the hypoglycemia. This treatment markedly reduced the endotoxin-induced electron microscopical changes in the kidneys and lungs. Although L-canavanine, like L-NAME, inhibited both cerebellar constitute and splenic inducible nitric oxide synthase in vitro, in contrast to L-NAME it did not modify either arterial blood pressure or carotid artery blood flow in control rats. The data are consistent with L-canavanine being a selective inhibitor of inducible nitric oxide synthase, at least in vivo, and suggest that inhibitors of this enzyme may be beneficial in endotoxin-induced shock. PMID:8885085

  4. PKCa Agonists Enhance the Protective Effect of Hyaluronic Acid on Nitric Oxide-Induced Apoptosis of Articular Chondrocytes in Vitro

    PubMed Central

    Zhou, Jian-lin; Fang, Hong-song; Peng, Hao; Hu, Qiong-jie; Liu, Shi-qing; Ming, Jiang-hua; Qiu, Bo

    2013-01-01

    Objective(s): Protein kinase C (PKC?) is involved in modulating articular chondrocytes apoptosis induced by nitric oxide (NO). Hyaluronic acid (HA) inhibits nitric oxide-induced apoptosis of articular chondrocytes by protecting PKC?, but the mechanism remains unclear. The present study was performed to investigate the effects and mechanisms of PKC? regulate protective effect of hyaluronic acid. Materials and Methods The ratio of apoptotic cell and cell viability was surveyed by PCNA and MTT assay. The expression of caspase-3 was determined by real-time PCR and western blot. Results: It was showed that HA was able to reduce the nuclei fragment and PCNA expression, and NO-induced articular apoptosis blocked by HA, pretreated chondrocytes with PMA, HA significantly inhibits the activation of caspase-3 induced by NO, but pretrement with CHR, HA significantly incresed the expression of caspase-3. Conclusion: The results may be showed that PKCa regulate the expresion of caspase-3, which contribute to the apoptosis of chondrocytes induced by NO. PKC ? agonists enhance the protective effect of hyaluronic acid on nitric oxide-induced articular chondrocytes apoptosis. PMID:24570835

  5. Inducible nitric oxide synthase (iNOS) expression in monocytes during acute Dengue Fever in patients and during in vitro infection

    Microsoft Academic Search

    Patrícia CF Neves-Souza; Elzinandes L Azeredo; Sonia MO Zagne; Rogério Valls-de-Souza; Sonia RNI Reis; Claire F Kubelka

    2005-01-01

    Mononuclear phagocytes are considered to be main targets for Dengue Virus (DENV) replication. These cells are activated after infection, producing proinflammatory mediators, including tumour-necrosis factor-?, which has also been detected in vivo. Nitric oxide (NO), usually produced by activated mononuclear phagocytes, has antimicrobial and antiviral activities. METHODS: The expression of DENV antigens and inducible nitric oxide synthase (iNOS) in human

  6. Mechanism of nitric oxide production induced by H2O2 in cultured endothelial cells.

    PubMed

    Shimizu, S; Ishii, M; Yamamoto, T; Momose, K

    1997-03-01

    This study examined the mechanism of stimulation of nitric oxide (NO) synthesis induced by hydrogen peroxide (H2O2). To determine the role of Ca2+ on H2O2-induced NO synthesis in bovine aortic endothelial cells, the increases in intracellular Ca2+ and NO production induced by H2O2 were compared with the effects of the Ca2+ ionophore ionomycin in the same batches of endothelial cells. NO production was assessed by formation of [3H]citrulline from [3H]arginine, and changes in intracellular Ca2+ were measured using fluorescent indicator fluo-3 with a confocal laser scanning system. Both H2O2 (1-10 mM) and ionomycin (10(-7)-10(-5) M) increased intracellular Ca2+ and stimulated the synthesis of L-citrulline from L-arginine. Although H2O2 induced only a small increase in intracellular Ca2+, it markedly increased L-citrulline formation compared with ionomycin. Thus, stimulation of NO synthesis induced by H2O2 may involve the mechanisms other than the increases in intracellular Ca2+ in endothelial cells. In the particulate fraction from cultured endothelial cells, addition of exogenous H2O2 (1 mM) or catalase (100 U/ml) did not affect L-citrulline formation. However, co-administration of H2O2 and catalase stimulated L-citrulline formation. These findings suggested that not only the increases in intracellular Ca2+ but also the products by the reaction with H2O2 and catalase are likely to be involved in the stimulation of NO synthesis induced by H2O2. PMID:9144831

  7. Protection against LPS-induced cartilage inflammation and degradation provided by a biological extract of Mentha spicata

    Microsoft Academic Search

    Wendy Pearson; Ronald S Fletcher; Laima S Kott; Mark B Hurtig

    2010-01-01

    BACKGROUND: A variety of mint [Mentha spicata] has been bred which over-expresses Rosmarinic acid (RA) by approximately 20-fold. RA has demonstrated significant anti-inflammatory activity in vitro and in small rodents; thus it was hypothesized that this plant would demonstrate significant anti-inflammatory activity in vitro. The objectives of this study were: a) to develop an in vitro extraction procedure which mimics

  8. Inhibition of soluble epoxide hydrolase reduces LPS-induced thermal hyperalgesia and mechanical allodynia in a rat model

    E-print Network

    Hammock, Bruce D.

    allodynia in a rat model of inflammatory pain Bora Inceoglu a , Steven L. Jinks b , Kara R. Schmelzer and that sEH inhibitors effectively attenuate thermal hyperalgesia and mechanical allodynia in rats treated

  9. Renal HIV Expression Is Unaffected by Serum LPS Levels in an HIV Transgenic Mouse Model of LPS Induced Kidney Injury

    Microsoft Academic Search

    Jeremy S. Leventhal; Zygimantas Alsauskas; Alexandra Snyder; Pengfei Gong; Bin Wang; Vivette DAgati; Michael J. Ross

    2011-01-01

    Acute kidney injury (AKI) is associated with increased rates of mortality. For unknown reasons, HIV infected individuals have a higher risk of AKI than uninfected persons. We tested our hypothesis that increased circulating LPS increases renal expression of HIV and that HIV transgenic (Tg26) mice have increased susceptibility to AKI. Tg26 mice harbor an HIV transgene encoding all HIV genes

  10. Norepinephrine enhances the LPS-induced expression of COX2 and secretion of PGE2 in primary rat microglia

    Microsoft Academic Search

    Johannes CM Schlachetzki; Bernd L Fiebich; Elisabeth Haake; Eduardo Candelario-Jalil; Michael T Heneka; Michael Hüll

    2010-01-01

    BACKGROUND: Recent studies suggest an important role for neurotransmitters as modulators of inflammation. Neuroinflammatory mediators such as cytokines and molecules of the arachidonic acid pathway are generated and released by microglia. The monoamine norepinephrine reduces the production of cytokines by activated microglia in vitro. However, little is known about the effects of norepinephrine on prostanoid synthesis. In the present study,

  11. Glycyrrhizic acid nanoparticles inhibit LPS-induced inflammatory mediators in 264.7 mouse macrophages compared with unprocessed glycyrrhizic acid

    PubMed Central

    Wang, Wei; Luo, Meng; Fu, Yujie; Wang, Song; Efferth, Thomas; Zu, Yuangang

    2013-01-01

    Glycyrrhizic acid (GA), the main component of radix glycyrrhizae, has a variety of pharmacological activities. In the present study, suspensions of GA nanoparticles with the average particle size about 200nm were prepared by a supercritical antisolvent (SAS) process. Comparative studies were undertaken using lipopolysaccardide(LPS)-stimulated mouse macrophages RAW 264.7 as in vitro inflammatory model. Several important inflammation mediators such as NO, PGE2, TNF-? and IL-6 were examined. These markers were highly stimulated by LPS and were inhibited both by nano-GA and unprocessed GA in a dose-dependent manner, especially PGE2 and TNF-?. However nano-GA and unprocessed GA inhibited NO only at a high concentration. In general, we found that GA nanoparticle suspensions exhibited much better anti-inflammatory activities compared to unprocessed GA. PMID:23610519

  12. Surfactant Protein A Differentially Regulates IFN g - and LPS-Induced Nitrite Production by Rat Alveolar Macrophages

    Microsoft Academic Search

    Cordula Stamme; Eric Walsh; Jo Rae

    Although several studies have demonstrated that the pulmo- nary collectins surfactant protein (SP)-A and SP-D contribute to innate immunity by enhancing pathogen phagocytosis, the role of SP-A and SP-D in regulating production of free radicals and cytokines is controversial. We hypothesized that the state and mechanism of activation of the immune cell influence its response to SP-A. The effects of

  13. LPS-induced serum TNF production and lethality in mice: effect of L-carnitine and some acyl-derivatives

    PubMed Central

    Ruggiero, Vito; D'Urso, Claudio M.; Albertoni, Claudio; Campo, Silvia; Martelli, Edoardo Arrigoni

    1993-01-01

    The effect of L-carnitine and some of its acyl derivatives on serum TNF production and lethality in a murine experimental endotoxin shock model was investigated. In some instances, serum IL-6 production was also evaluated. In this experimental model, C57BL/6 mice received 30 mg/kg LPS (E. cell 055:B5) injected intraperitoneally, while L-carnitine and its derivatives were administered according to different schedules. Serum levels of TNF and IL-6 were evaluated 1 h following LPS injection. The treated animals were also monitored daily for differences in body temperature, feeding, and survival for 10 days after LPS injection. Although some derivatives were able to significantly affect TNF production, the marked decrease in serum TNF levels of LPS-treated mice was not paralleled by a substantial increase in survival. PMID:18475570

  14. Inhibition of LPS-induced activation of alveolar macrophages by high concentrations of LPS-binding protein

    Microsoft Academic Search

    Lutz Hamann; Cordula Stamme; Artur J Ulmer; Ralf R Schumann

    2002-01-01

    Lipopolysaccharide (LPS)-binding protein regulates the effects of LPS on immunocompetent cells. By catalyzing the binding of LPS to membrane CD14, LPS-binding protein (LBP) potentiates both the inflammatory response and internalization of LPS. LBP-mediated transport of LPS into high density lipoprotein particles participates in LPS clearance. Elevated serum levels of LBP have been shown to elicit protective effects in vivo. Because

  15. LPS-induced suppression of macrophage cholesterol efflux is mediated by adipocyte enhancer-binding protein 1

    Microsoft Academic Search

    Amin Majdalawieh; Hyo-Sung Ro

    2009-01-01

    Macrophages facilitate clearance of cholesterol from the body via reverse cholesterol transport (RCT). The first event in RCT is internalization of modified low density lipoprotein by macrophages, upon which PPAR?1 and LXR? signaling pathways are turned on, leading to the transactivation of a cascade of genes (e.g. ABCA1 and ABCG1), whose products promote macrophage cholesterol efflux. Down-regulation of macrophage cholesterol

  16. Inhibitors of nitric oxide synthetase prevent castor-oil-induced diarrhoea in the rat.

    PubMed Central

    Mascolo, N.; Izzo, A. A.; Barbato, F.; Capasso, F.

    1993-01-01

    1. Castor oil (2 ml orally) produced copious diarrhoea in rats 3 h after its administration. 2. Pretreatment (intraperitoneal, i.p.) of rats with the NO synthesis inhibitors NG-nitro-L-arginine methyl ester (L-NAME, 1-25 mg kg-1) and NG-monomethyl-L-arginine (L-NMMA, 2.5-100 mg kg-1) inhibited or prevented castor-oil-induced diarrhoea. L-Arginine (150-600 mg kg-1, i.p.) administered to rats pretreated with L-NAME 10 mg kg-1, drastically reduced the antidiarrhoeal activity of L-NAME in a dose-related manner. D-Arginine (900 mg kg-1) did not modify the protection by L-NAME. 3. Pretreatment (i.p.) of rats with L-NAME (2.5-25 mg kg-1) decreased the intestinal fluid accumulation and Na+ secretion induced by castor oil. L-Arginine (600 mg kg-1) but not D-arginine (900 mg kg-1) counteracted the inhibitory effect of L-NAME (10 mg kg-1). 4. L-NAME (10 and 25 mg kg-1) had no significant effect on the intestinal transit in normal rats or those given castor oil. 5. These results provide evidence that nitric oxide (NO) could play an important role in castor-oil-induced diarrhoea. PMID:7683565

  17. Involvement of Syk kinase in TNF-induced nitric oxide production by airway epithelial cells

    SciTech Connect

    Ulanova, Marina [Department of Medicine, University of Alberta, Edmonton, Alta. (Canada)]. E-mail: marina.ulanova@normed.ca; Marcet-Palacios, Marcelo [Department of Medicine, University of Alberta, Edmonton, Alta. (Canada); Munoz, Samira [Department of Medicine, University of Alberta, Edmonton, Alta. (Canada); Asfaha, Samuel [Department of Medicine, University of Alberta, Edmonton, Alta. (Canada); Kim, Moo-Kyung [University of Pennsylvania School of Medicine, Philadelphia, PA (United States); Schreiber, Alan D. [University of Pennsylvania School of Medicine, Philadelphia, PA (United States); Befus, A. Dean [Department of Medicine, University of Alberta, Edmonton, Alta. (Canada)

    2006-12-15

    We have recently found that Syk is widely expressed in lung epithelial cells (EC) and participates in {beta}1 integrin signaling. In this study, we assessed the role of Syk in regulation of NO production. Stimulation of human bronchial EC line HS-24 by TNF caused an increased expression of inducible nitric oxide synthase (iNOS). Inhibition of Syk using siRNA or piceatannol down-regulated the iNOS expression and reduced NO production. This effect occurred in EC simultaneously stimulated via {beta}1 integrins, suggesting that TNF and {beta}1 integrins provide co-stimulatory signals. Inhibition of Syk down-regulated TNF-induced p38 and p44/42 MAPK phosphorylation and nuclear translocation of p65 NF-{kappa}B. Thus, TNF-induced activation of pro-inflammatory signaling in EC leading to enhanced expression of iNOS and NO production was dependent on Syk. Syk-mediated signaling regulates NO production at least partly via activating the MAPK cascade. Understanding the role of Syk in airway EC may help in developing new therapeutic tools for inflammatory lung disorders.

  18. Vanadate-induced nitric oxide production: role in osteoblast growth and differentiation.

    PubMed

    Cortizo, A M; Caporossi, M; Lettieri, G; Etcheverry, S B

    2000-07-21

    Nitric oxide (NO) has been shown to act as a mediator of cytokines in bone tissue. We have previously demonstrated that vanadium compounds are insulin- and growth factor-mimetic compounds in osteoblasts in culture, although high doses are toxic to these cells. In this study, we measured NO production in two osteoblast-like cells (UMR106 and MC3T3E1) incubated with different concentrations (2.5-100 microM) of vanadate. Vanadate induced NO release in a biphasic manner, with levels being significantly increased at concentrations over 50 microM. The NO donor, sodium nitroprusside, mimicked the vanadate effect: it inhibited cell growth and alkaline phosphatase activity in a dose-dependent manner. Vanadate enhanced the NO synthases, the endothelial and inducible (eNOS and iNOS) isoforms, in a dose-dependent manner. Experiments performed with the ionophore A23187 and EGTA suggested that vanadate-induced NO production involves Ca(2+)-dependent and -independent mechanisms. Altogether, our results suggest that NO may play a critical role in the bioactivity of vanadium in osteoblast-like cells. PMID:10988345

  19. Inhibition by ginkgolides and bilobalide of the production of nitric oxide in macrophages (THP1) but not in endothelial cells (HUVEC) 1 1 Abbreviations: NO, nitric oxide; NOS, nitric oxide synthase; iNOS, inducible NOS; eNOS, endothelial NOS; EGb, extracts of Ginkgo biloba leaves; THP1, a human monocytic cell line; HUVEC, human umbilical vein endothelial cells; and RT–PCR, reverse transcription–polymerase chain reaction

    Microsoft Academic Search

    Filly Cheung; Yaw L. Siow; Karmin O

    2001-01-01

    Nitric oxide (NO) is a principal mediator in many physiological and pathological processes. NO produced by constitutive nitric oxide synthase in endothelial cells (eNOS) acts as a vasodilator, whereas excess NO production due to elevated expression of inducible nitric oxide synthase (iNOS) may produce cytotoxic effects to cells in the vascular wall. We demonstrated in our previous work that the

  20. Altered regulation of nitric oxide and natriuretic peptide system in cisplatin-induced nephropathy.

    PubMed

    Kim, Chang Seong; Choi, Joon Seok; Park, Jeong Woo; Bae, Eun Hui; Ma, Seong Kwon; Lee, Jongun; Kim, Soo Wan

    2012-02-10

    Cisplatin is a chemotherapeutic agent used for treating solid tumors. However, nephrotoxicity is the dose-limiting factor in its clinical use. The present study was aimed to determine whether altered regulation of the local nitric oxide (NO) and natriuretic peptide (NP) systems is involved in the pathogenesis of cisplatin-induced nephropathy. Cisplatin (6 mg/kg) was injected intraperitoneally into male Sprague-Dawley rats. The control group was not treated with cisplatin. Expression levels of nitric oxide synthase (NOS), nitrotyrosine, soluble guanylyl cyclase and neutral endopeptidase (NEP) in the kidneys were determined 4 days after treatment by semiquantitative immunoblotting. mRNA expression of NPs and natriuretic peptide receptors (NPRs) was determined by real-time polymerase chain reaction. The activities of soluble and particulate guanylyl cyclase were determined by measuring the amount of cyclic 3',5'-guanosine monophosphate (cGMP) generated in responses to sodium nitroprusside and atrial natriuretic peptide (ANP), respectively. In the test rats, creatinine clearance was decreased, while sodium and water excretion were increased. The expression of inducible NOS (iNOS) and nitrotyrosine was increased in the cortex/outer stripe of outer medullar and inner medullar, while that of endothelial and neuronal NOS was decreased in the inner medullar. Excretion of NO metabolites was increased in these rats. The catalytic activity of soluble guanyly cyclase was blunted in the papilla after cisplatin was administered. The mRNA expression of ANP, brain natriuretic peptide, and C-type natriuretic peptide was increased, while that of NPR-A and NPR-C were decreased in the test rats. The catalytic activity of soluble and particulate guanylyl cyclase in the papilla was blunted after cisplatin was administered. In conclusion, increased production of NO by iNOS may contribute to cytotoxic injury, resulting in cisplatin-induced nephropathy, while the up-regulation of renal natriuretic peptide synthesis together with the down-regulation of NEP and NPR-C may contribute to the natriuresis and diuresis seen in cisplatin-induced nephropathy. PMID:22209992

  1. Dual effect of interferon (IFN?)-induced nitric oxide on tumorigenesis and intracellular bacteria.

    PubMed

    Zea, Arnold H; Aiyar, Ashok; Tate, David

    2014-01-01

    Nitric oxide (NO) is a key messenger involved in numerous physiological functions including inflammatory and immune responses. The functions of NO and their underlying mechanisms have been elucidated by extensive studies over the past 10 years. However, the complexity of the interactions between different levels of NO and multiple aspects of tumor development/progression as well as bacterial pathogenesis has led to apparently conflicting findings. The precise role of NO in bacterial and tumor pathogenesis involves a multitude of inter- and intracellular signaling pathways in which interferon gamma signaling and L-arginine metabolism are the major pathways involved in NO synthesis and regulation. The availability of the amino acid L-Arg can be a key factor to control the expression of inducible nitric oxide synthase (NOS2) and cellular NO levels. The role played by the NOS2/NO system both in bacterial pathogenesis and in tumor development is complex due to the dual role these molecules can play promoting or inhibiting infections and cancer. This duality brings to the table a double challenge to determine the net impact of NO on cancer or bacterial behavior and to define the therapeutic role of NO-centered anticancer or antibacterial strategies. We believe that a comprehensive and dynamic understanding of the cascade of molecular and cellular events underlying tumor biology and bacterial pathogenesis that are affected by NO will allow researchers to exploit the potential antitumor and antibacterial properties of drugs interfering with NO metabolism. The contrasting roles of NO/NOS2 in these processes are clarified in this chapter. PMID:25189392

  2. Fourier transform infrared spectroscopy study of ligand photodissociation and migration in inducible nitric oxide synthase

    PubMed Central

    Horn, Michael; Nienhaus, Karin; Nienhaus, Gerd Ulrich

    2014-01-01

    Inducible nitric oxide synthase (iNOS) is a homodimeric heme enzyme that catalyzes the formation of nitric oxide (NO) from dioxygen and L-arginine (L-Arg) in a two-step process. The produced NO can either diffuse out of the heme pocket into the surroundings or it can rebind to the heme iron and inhibit enzyme action. Here we have employed Fourier transform infrared (FTIR) photolysis difference spectroscopy at cryogenic temperatures, using the carbon monoxide (CO) and NO stretching bands as local probes of the active site of iNOS. Characteristic changes were observed in the spectra of the heme-bound ligands upon binding of the cofactors. Unlike photolyzed CO, which becomes trapped in well-defined orientations, as indicated by sharp photoproduct bands, photoproduct bands of NO photodissociated from the ferric heme iron were not visible, indicating that NO does not reside in the protein interior in a well-defined location or orientation. This may be favorable for NO release from the enzyme during catalysis because it reduces self-inhibition. Moreover, we used temperature derivative spectroscopy (TDS) with FTIR monitoring to explore the dynamics of NO and carbon monoxide (CO) inside iNOS after photodissociation at cryogenic temperatures. Only a single kinetic photoproduct state was revealed, but no secondary docking sites as in hemoglobins. Interestingly, we observed that intense illumination of six-coordinate ferrous iNOS oxy-NO ruptures the bond between the heme iron and the proximal thiolate to yield five-coordinate ferric iNOS oxy-NO, demonstrating the strong trans effect of the heme-bound NO. PMID:25653844

  3. Inducible nitric oxide synthase expression in human colorectal cancer: correlation with tumor angiogenesis.

    PubMed

    Cianchi, Fabio; Cortesini, Camillo; Fantappiè, Ornella; Messerini, Luca; Schiavone, Nicola; Vannacci, Alfredo; Nistri, Silvia; Sardi, Iacopo; Baroni, Gianna; Marzocca, Cosimo; Perna, Federico; Mazzanti, Roberto; Bechi, Paolo; Masini, Emanuela

    2003-03-01

    To investigate the potential involvement of the nitric oxide (NO) pathway in colorectal carcinogenesis, we correlated the expression and the activity of inducible nitric oxide synthase (iNOS) with the degree of tumor angiogenesis in human colorectal cancer. Tumor samples and adjacent normal mucosa were obtained from 46 surgical specimens. Immunohistochemical expression of iNOS, vascular endothelial growth factor (VEGF), and CD31 was analyzed on paraffin-embedded tissue sections. iNOS activity and cyclic GMP levels were assessed by specific biochemical assays. iNOS protein expression was determined by Western blot analysis. iNOS and VEGF mRNA levels were evaluated using Northern blot analysis. Both iNOS and VEGF expressions correlated significantly with intratumor microvessel density (r(s) = 0.31, P = 0.02 and r(s) = 0.67, P < 0.0001, respectively). A significant correlation was also found between iNOS and VEGF expression (P = 0.001). iNOS activity and cyclic GMP production were significantly higher in the cancer specimens than in the normal mucosa (P < 0.0001 and P < 0.0001, respectively), as well as in metastatic tumors than in nonmetastatic ones (P = 0.002 and P = 0.04, respectively). Western and Northern blot analyses confirmed the up-regulation of the iNOS protein and gene in the tumor specimens as compared with normal mucosa. NO seems to play a role in colorectal cancer growth by promoting tumor angiogenesis. PMID:12598314

  4. Homocysteine stimulates inducible nitric oxide synthase expression in macrophages: antagonizing effect of ginkgolides and bilobalide.

    PubMed

    Woo, Connie W H; Cheung, Filly; Chan, Vincent W H; Siow, Yaw L; O, Karmin

    2003-01-01

    Hyperhomocysteinemia is an independent risk factor for atherosclerotic diseases. Inducible nitric oxide synthase (iNOS) is mainly expressed in macrophages upon stimulation. Overproduction of nitric oxide (NO) by iNOS can exacerbate the development of atherosclerosis. Our previous studies demonstrated that the extract of ginkgo biloba leaves (EGb) inhibited the iNOS-mediated NO production in monocyte-derived macrophage. We also reported that homocysteine could stimulate monocyte chemoattractant protein-1 (MCP-1) expression in vascular cells causing enhanced monocyte chemotaxis. The objective of the present study was to investigate the effect of homocysteine on iNOS-mediated NO production in macrophages and the antagonizing effect of EGb. Human monocytic cell (THP-1)-derived macrophages were incubated with homocysteine for various time periods. Homocysteine at concentrations of 0.05-0.1 mM significantly stimulated NO production and iNOS activity in macrophages via increased expression of iNOS mRNA and protein. The increased iNOS expression was associated with activation of nuclear factor-kappa B (NF-kappaB) arising from reduced expression of inhibitor protein (IkappaB alpha) mRNA as well as increased phosphorylation of IkappaB alpha protein in homocysteine-treated cells. EGb and its terpenoids (ginkgolide A, ginkgolide B and bilobalide) could antagonize the homocysteine effect on iNOS expression in macrophages via their antioxidant effect resulting in attenuation of NF-kappaB activation. Taken together, our results have demonstrated that homocysteine, at pathophysiological concentrations, stimulates iNOS-mediated NO production in macrophages. EGb and its terpenoids can antagonize such stimulatory effect via antioxidation and attenuation of NF-kappaB activation. PMID:12619887

  5. TNF-? dependent production of inducible nitric oxide is involved in PGE1 protection against acute liver injury

    PubMed Central

    Muntane, J; Rodriguez, F; Segado, O; Quintero, A; Lozano, J; Siendones, E; Pedraza, C; Delgado, M; O'Valle, F; Garcia, R; Montero, J; De la Mata, M; Mino, G

    2000-01-01

    BACKGROUND—Tumour necrosis factor ? (TNF-?) and nitric oxide modulate damage in several experimental models of liver injury. We have previously shown that protection against D-galactosamine (D-GalN) induced liver injury by prostaglandin E1 (PGE1) was accompanied by an increase in TNF-? and nitrite/nitrate in serum.?AIMS—The aim of the present study was to evaluate the role of TNF-? and nitric oxide during protection by PGE1 of liver damage induced by D-GalN.?METHODS—Liver injury was induced in male Wistar rats by intraperitoneal injection of 1 g/kg of D-GalN. PGE1 was administered 30 minutes before D-GalN. Inducible nitric oxide synthase (iNOS) was inhibited by methylisothiourea (MT), and TNF-? concentration in serum was lowered by administration of anti-TNF-? antibodies. Liver injury was evaluated by alanine aminotransferase activity in serum, and histological examination and DNA fragmentation in liver. TNF-? and nitrite/nitrate concentrations were determined in serum. Expression of TNF-? and iNOS was also assessed in liver sections.?RESULTS—PGE1 decreased liver injury and increased TNF-? and nitrite/nitrate concentrations in serum of rats treated with D-GalN. PGE1 protection was related to enhanced expression of TNF-? and iNOS in hepatocytes. Administration of anti-TNF-? antibodies or MT blocked the protection by PGE1 of liver injury induced by D-GalN.?CONCLUSIONS—This study suggests that prior administration of PGE1 to D-GalN treated animals enhanced expression of TNF-? and iNOS in hepatocytes, and that this was causally related to protection by PGE1 against D-GalN induced liver injury.???Keywords: tumour necrosis factor ?; nitric oxide; prostaglandin E1; methylisothiourea; D-galactosamine; liver injury PMID:10986217

  6. Comparison between the role of the neuronal and inducible nitric oxide synthase in methamphetamine-induced neurotoxicity and sensitization.

    PubMed

    Itzhak, Y; Martin, J L; Ali, S F

    2000-09-01

    The involvement of the neuronal and inducible nitric oxide synthase (nNOS and iNOS, respectively) in methamphetamine (METH)-induced dopaminergic neurotoxicity and behavioral sensitization was investigated. To determine METH-induced neurotoxicity, mice deficient in the nNOS and iNOS genes, nNOS(-/-) and iNOS(-/-) mice, and wild-type controls received either saline or METH (5 mg/kg x 3). After 72 h the level of striatal dopaminergic markers were measured. Administration of METH to nNOS(-/-) mice had no significant effect on the level of striatal dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), or dopamine transporter (DAT) binding sites. However, METH caused 25-40% depletion of dopaminergic markers in iNOS(-/-) mice and 63-69% depletion in the wild-type mice. METH-induced locomotor activity was measured following the administration of a low dose (1 mg/kg) on day 1. Subsequently animals received the high dose of METH (5 mg/kg x 3). On day 4, after a 68-72 h drug free period, animals were challenged with 1 mg/kg METH, and locomotor activity was recorded. The intensity of METH-induced locomotion in nNOS(-/-) mice on day 1 and 4 was similar, suggesting that locomotor sensitization did not develop. However, the intensity of METH-induced locomotion in the iNOS(-/-) and wild-type mice on day 4 was doubled compared to day 1, suggesting the development of sensitization. The present findings indicate that nNOS(-/-) mice are more resistant to METH-induced neurotoxicity and behavioral sensitization than iNOS(-/-) mice. These results suggest a major role for nNOS rather than iNOS in the effects of METH. PMID:11085313

  7. Role of Polymorphisms of Inducible Nitric Oxide Synthase and Endothelial Nitric Oxide Synthase in Idiopathic Environmental Intolerances

    PubMed Central

    De Luca, Chiara; Gugliandolo, Agnese; Calabrò, Carlo; Currò, Monica; Ientile, Riccardo; Raskovic, Desanka; Korkina, Ludmila; Caccamo, Daniela

    2015-01-01

    Oxidative stress and inflammation play a pathogenetic role in idiopathic environmental intolerances (IEI), namely, multiple chemical sensitivity (MCS), fibromyalgia (FM), and chronic fatigue syndrome (CFS). Given the reported association of nitric oxide synthase (NOS) gene polymorphisms with inflammatory disorders, we aimed to investigate the distribution of NOS2A ?2.5?kb (CCTTT)n as well as Ser608Leu and NOS3 ?786T>C variants and their correlation with nitrite/nitrate levels, in a study cohort including 170 MCS, 108 suspected MCS (SMCS), 89 FM/CFS, and 196 healthy subjects. Patients and controls had similar distributions of NOS2A Ser608Leu and NOS3 ?786T>C polymorphisms. Interestingly, the NOS3 ?786TT genotype was associated with increased nitrite/nitrate levels only in IEI patients. We also found that the NOS2A ?2.5?kb (CCTTT)11 allele represents a genetic determinant for FM/CFS, and the (CCTTT)16 allele discriminates MCS from SMCS patients. Instead, the (CCTTT)8 allele reduces by three-, six-, and tenfold, respectively, the risk for MCS, SMCS, and FM/CFS. Moreover, a short number of (CCTTT) repeats is associated with higher concentrations of nitrites/nitrates. Here, we first demonstrate that NOS3 ?786T>C variant affects nitrite/nitrate levels in IEI patients and that screening for NOS2A ?2.5?kb (CCTTT)n polymorphism may be useful for differential diagnosis of various IEI. PMID:25878398

  8. Bacillus anthracis-derived nitric oxide induces protein S-nitrosylation contributing to macrophage death.

    PubMed

    Chung, Myung-Chul; Narayanan, Aarthi; Popova, Taissia G; Kashanchi, Fatah; Bailey, Charles L; Popov, Serguei G

    2013-01-01

    Bacillus anthracis, a causative agent of anthrax, is able to germinate and survive within macrophages. A recent study suggested that B. anthracis-derived nitric oxide (bNO) is a key aspect of bacterial defense that protects bacterial DNA from oxidative burst in the macrophages. However, the virulent effect of bNO in host cells has not been investigated. Here, we report that bNO contributes macrophage killing by S-nitrosylation of bioenergetic-relating proteins within mitochondria. Toxigenic Sterne induces expression of the bnos gene and produces bNO during early stage of infection. Nitroso-proteomic analysis coupled with a biotin-switch technique demonstrated that toxigenic infection induces protein S-nitrosylation in B. anthracis-susceptible RAW264.7. For each target enzyme tested (complex I, complex III and complex IV), infection by B. anthracis Sterne caused enzyme inhibition. N?-nitro-L-arginine methyl ester, a NO synthase inhibitor, reduced S-nitrosylation and partially restored cell viability evaluated by intracellular ATP levels in macrophages. Our data suggest that bNO leads to energy depletion driven by impaired mitochondrial bioenergetic machinery that ultimately contributes to macrophage death. This novel mechanism of anthrax pathogenesis may offer specific approach to the development of therapeutics. PMID:23178574

  9. Does nitric oxide mediate circulatory failure induced by 35-GHz microwave heating?

    PubMed

    Ryan, K L; Frei, M R; Berger, R E; Jauchem, J R

    1996-07-01

    The purpose of this study was to determine whether nitric oxide (NO) contributes to the hypotensive state induced by exposure to radiofrequency radiation of millimeter-wavelength (MMW). This was accomplished using a synthetic analogue of L-arginine, N omega-nitro-L-arginine methyl ester (L-NAME), to competitively inhibit NO synthesis. Ketamine-anesthetized rats were instrumented for the measurement of arterial blood pressure, ECG, and temperature at five sites. Animals were exposed to 35-GHz radiofrequency radiation until mean arterial pressure (MAP) decreased to 75 mmHg. MMW exposure was then halted and either saline or L-NAME (1, 2.5, 5, or 10 mg/kg) was administered; each rat received only one dose. Following irradiation, L-NAME at each dose produced a peak increase in MAP that was smaller than that produced by the same dose of L-NAME in nonirradiated rats. There was no difference in post-MMW survival times between L-NAME-and saline-treated rats. These results indicate that bolus administration of L-NAME does not reverse hypotension induced by 35-GHz microwave heating, suggesting that excess levels of NO do not mediate this form of circulatory failure. PMID:8828089

  10. Astrocytes enhance lipopolysaccharide-induced nitric oxide production by microglial cells.

    PubMed

    Solà, Carme; Casal, Carme; Tusell, Josep M; Serratosa, Joan

    2002-10-01

    Several stimuli result in glial activation and induce nitric oxide (NO) production in microglial and astroglial cells. The bacterial endotoxin lipopolysaccharide (LPS) has been widely used to achieve glial activation in vitro, and several studies show that both microglial and, to a lesser extent, astroglial cell cultures produce NO after LPS treatment. However, NO production in endotoxin-treated astrocyte cultures is controversial. We characterized NO production in microglial, astroglial and mixed glial cell cultures treated with lipopolysaccharide, measured as nitrite accumulation in the culture media. We also identified the NO-producing cells by immunocytochemistry, using specific markers for the inducible NO synthase (iNOS) isoform, microglial and astroglial cells. Only microglial cells showed iNOS immunoreactivity. Thus, contaminating microglial cells were responsible for NO production in the secondary astrocyte cultures. We then analysed the effect of astrocytes on NO production by microglial cells using microglial-astroglial cocultures, and we observed that this production was clearly enhanced in the presence of astroglial cells. Soluble factors released by astrocytes did not appear to be directly responsible for such an effect, whereas nonsoluble factors present in the cell membrane of LPS-treated astrocytes could account, at least in part, for this enhancement. PMID:12405988

  11. Exogenous nitric oxide protect cucumber roots against oxidative stress induced by salt stress.

    PubMed

    Shi, Qinghua; Ding, Fei; Wang, Xiufeng; Wei, Min

    2007-08-01

    Mitochondria are subcellular organelles with an essentially oxidative type of metabolism. The production of reactive oxygen species (ROS) in it increases under stress conditions and causes oxidative damage. In the present study, effects of exogenous sodium nitroprusside (SNP), a nitric oxide (NO) donor, on both the ROS metabolism in mitochondria and functions of plasma membrane (PM) and tonoplast were studied in cucumber seedlings treated with 100mM NaCl. NaCl treatment induced significant accumulation of H(2)O(2) and led to serious lipid peroxidation in cucumber mitochondria, and the application of 50muM SNP stimulated ROS-scavenging enzymes and reduced accumulation of H(2)O(2) in mitochondria of cucumber roots induced by NaCl. As a result, lipid peroxidation of mitochondria decreased. Further investigation showed that application of SNP alleviated the inhibition of H(+)-ATPase and H(+)-PPase in PM and/or tonoplast by NaCl. While application of sodium ferrocyanide (an analog of SNP that does not release NO) did not show the effect of SNP, furthermore, the effects of SNP were reverted by addition of hemoglobin (a NO scavenger). PMID:17606379

  12. Orally administered melatonin prevents lipopolysaccharide-induced neural tube defects in mice.

    PubMed

    Fu, Lin; Yu, Zhen; Chen, Yuan-Hua; Xia, Mi-Zhen; Wang, Hua; Zhang, Cheng; Tao, Fang-Biao; Xu, De-Xiang

    2014-01-01

    Lipopolysaccharide (LPS) has been associated with adverse pregnant outcomes, including fetal demise, intra-uterine growth restriction (IUGR), neural tube defects (NTDs) and preterm delivery in rodent animals. Previous studies demonstrated that melatonin protected against LPS-induced fetal demise, IUGR and preterm delivery. The aim of the present study was to investigate the effects of melatonin on LPS-induced NTDs. All pregnant mice except controls were intraperitoneally injected with LPS (25 µg/kg) daily from gestational day (GD)8 to GD12. Some pregnant mice were orally administered with melatonin (MT, 50 mg/kg) before each LPS injection. A five-day LPS injection resulted in 27.5% of fetuses with anencephaly, exencephaly or encephalomeningocele. Additional experiment showed that maternal LPS exposure significantly down-regulated placental proton-coupled folate transporter (pcft) and disturbed folate transport from maternal circulation through the placentas into the fetus. Interestingly, melatonin significantly attenuated LPS-induced down-regulation of placental pcft. Moreover, melatonin markedly improved the transport of folate from maternal circulation through the placentas into the fetus. Correspondingly, orally administered melatonin reduced the incidence of LPS-induced anencephaly, exencephaly or encephalomeningocele. Taken together, these results suggest that orally administered melatonin prevents LPS-induced NTDs through alleviating LPS-induced disturbance of folate transport from maternal circulation through the placenta into the fetus. PMID:25420102

  13. Orally Administered Melatonin Prevents Lipopolysaccharide-Induced Neural Tube Defects in Mice

    PubMed Central

    Chen, Yuan-Hua; Xia, Mi-Zhen; Wang, Hua; Zhang, Cheng; Tao, Fang-Biao; Xu, De-Xiang

    2014-01-01

    Lipopolysaccharide (LPS) has been associated with adverse pregnant outcomes, including fetal demise, intra-uterine growth restriction (IUGR), neural tube defects (NTDs) and preterm delivery in rodent animals. Previous studies demonstrated that melatonin protected against LPS-induced fetal demise, IUGR and preterm delivery. The aim of the present study was to investigate the effects of melatonin on LPS-induced NTDs. All pregnant mice except controls were intraperitoneally injected with LPS (25 µg/kg) daily from gestational day (GD)8 to GD12. Some pregnant mice were orally administered with melatonin (MT, 50 mg/kg) before each LPS injection. A five-day LPS injection resulted in 27.5% of fetuses with anencephaly, exencephaly or encephalomeningocele. Additional experiment showed that maternal LPS exposure significantly down-regulated placental proton-coupled folate transporter (pcft) and disturbed folate transport from maternal circulation through the placentas into the fetus. Interestingly, melatonin significantly attenuated LPS-induced down-regulation of placental pcft. Moreover, melatonin markedly improved the transport of folate from maternal circulation through the placentas into the fetus. Correspondingly, orally administered melatonin reduced the incidence of LPS-induced anencephaly, exencephaly or encephalomeningocele. Taken together, these results suggest that orally administered melatonin prevents LPS-induced NTDs through alleviating LPS-induced disturbance of folate transport from maternal circulation through the placenta into the fetus. PMID:25420102

  14. Resveratrol Induces Hepatic Mitochondrial Biogenesis Through the Sequential Activation of Nitric Oxide and Carbon Monoxide Production

    PubMed Central

    Kim, Seul-Ki; Joe, Yeonsoo; Zheng, Min; Kim, Hyo Jeong; Yu, Jae-Kyoung; Cho, Gyeong Jae; Chang, Ki Churl; Kim, Hyoung Kyu; Han, Jin; Ryter, Stefan W.

    2014-01-01

    Abstract Aims: Nitric oxide (NO) can induce mitochondrial biogenesis in cultured cells, through increased guanosine 3?,5?-monophosphate (cGMP), and activation of peroxisome proliferator-activated receptor gamma coactivator-1? (PGC-1?). We sought to determine the role of NO, heme oxygenase-1 (HO-1), and its reaction product (carbon monoxide [CO]) in the induction of mitochondrial biogenesis by the natural antioxidant resveratrol. Results: S-nitroso-N-acetylpenicillamine (SNAP), an NO donor, induced mitochondrial biogenesis in HepG2 hepatoma cells, and in vivo, through stimulation of PGC-1?. NO-induced mitochondrial biogenesis required cGMP, and was mimicked by the cGMP analogue (8-bromoguanosine 3?,5?-cyclic monophosphate [8-Br-cGMP]). Activation of mitochondrial biogenesis by SNAP required HO-1, as it could be reversed by genetic interference of HO-1; and by treatment with the HO inhibitor tin-protoporphyrin-IX (SnPP) in vitro and in vivo. Cobalt protoporphyrin (CoPP)-IX, an HO-1 inducing agent, stimulated mitochondrial biogenesis in HepG2 cells, which could be reversed by the CO scavenger hemoglobin. Application of CO, using the CO-releasing molecule-3 (CORM-3), stimulated mitochondrial biogenesis in HepG2 cells, in a cGMP-dependent manner. Both CoPP and CORM-3-induced mitochondrial biogenesis required NF-E2-related factor-2 (Nrf2) activation and phosphorylation of Akt. The natural antioxidant resveratrol induced mitochondrial biogenesis in HepG2 cells, in a manner dependent on NO biosynthesis, cGMP synthesis, Nrf2-dependent HO-1 activation, and endogenous CO production. Furthermore, resveratrol preserved mitochondrial biogenesis during lipopolysaccharides-induced hepatic inflammation in vivo. Innovation and Conclusions: The complex interplay between endogenous NO and CO production may underlie the mechanism by which natural antioxidants induce mitochondrial biogenesis. Strategies aimed at improving mitochondrial biogenesis may be used as therapeutics for the treatment of diseases involving mitochondrial dysfunction. Antioxid. Redox Signal. 20, 2589–2605. PMID:24041027

  15. Arsenite induces endothelial cytotoxicity by down-regulation of vascular endothelial nitric oxide synthase

    SciTech Connect

    Tsou, T.-C. [Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 100 Shih-Chuan 1st Road, Kaohsiung 807 (China)]. E-mail: tctsou@nhri.org.tw; Tsai, F.-Y. [Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 100 Shih-Chuan 1st Road, Kaohsiung 807 (China); Hsieh, Y.-W. [Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 100 Shih-Chuan 1st Road, Kaohsiung 807 (China); Li, L.-A. [Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 100 Shih-Chuan 1st Road, Kaohsiung 807 (China); Yeh, S.C [Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 100 Shih-Chuan 1st Road, Kaohsiung 807 (China); Chang, L.W. [Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 100 Shih-Chuan 1st Road, Kaohsiung 807 (China)

    2005-11-01

    Epidemiological studies have demonstrated a high association of inorganic arsenic exposure with vascular diseases. Recent research has also linked this vascular damage to impairment of endothelial nitric oxide synthase (eNOS) function by arsenic exposure. However, the role of eNOS in regulating the arsenite-induced vascular dysfunction still remains to be clarified. In our present study, we investigated the effect of arsenite on Akt1 and eNOS and its involvement in cytotoxicity of vascular endothelial cells. Our study demonstrated that arsenite decreased the protein levels of both Akt1 and eNOS accompanied with increased levels of ubiquitination of total cell lysates. We found that inhibition of the ubiquitin-proteasome pathway by MG-132 could partially protect Akt1 and eNOS from degradation by arsenite together with a proportional protection from the arsenite-induced cytoxicity. Moreover, up-regulation of eNOS protein expression significantly attenuated the arsenite-induced cytotoxicity and eNOS activity could be significantly inhibited after incubation with arsenite for 24 h in a cell-free system. Our study indicated that endothelial eNOS activity could be attenuated by arsenite via the ubiquitin-proteasome-mediated degradation of Akt1/eNOS as well as via direct inhibition of eNOS activity. Our study also demonstrated that eNOS actually played a protective role in arsenite-induced cytoxicity. These observations supported the hypothesis that the impairment of eNOS function by arsenite is one of the mechanisms leading to vascular changes and diseases.

  16. The Mechanism of Helium-Induced Preconditioning: A Direct Role for Nitric Oxide in Rabbits

    PubMed Central

    Pagel, Paul S.; Krolikowski, John G.; Pratt, Phillip F.; Shim, Yon Hee; Amour, Julien; Warltier, David C.; Weihrauch, Dorothee

    2008-01-01

    BACKGROUND Helium produces preconditioning against myocardial infarction by activating prosurvival signaling, but whether nitric oxide (NO) generated by endothelial NO synthase plays a role in this phenomenon is unknown. We tested the hypothesis that NO mediates helium-induced cardioprotection in vivo. METHODS Rabbits (n = 62) instrumented for hemodynamic measurement were subjected to a 30-min left anterior descending coronary artery occlusion and 3 h reperfusion, and received 0.9% saline (control) or three cycles of 70% helium–30% oxygen administered for 5 min interspersed with 5 min of an air–oxygen mixture before left anterior descending coronary artery occlusion in the absence or presence of pretreatment with the nonselective NOS inhibitor N-nitro-l-arginine methyl ester (L-NAME; 10 mg/kg), the selective inducible NOS inhibitor aminoguanidine hydrochloride (AG; 300 mg/kg), or selective neuronal NOS inhibitor 7-nitroindazole (7-NI; 50 mg/kg). In additional rabbits, the fluorescent probe 4,5-diaminofluroscein diacetate (DAF-2DA) and confocal laser microscopy were used to detect NO production in the absence or presence of helium with or without L-NAME pretreatment. RESULTS Helium reduced (P < 0.05) infarct size (24% ± 4% of the left ventricular area at risk; mean ± sd) compared with control (46% ± 3%). L-NAME, AG, and 7-NI did not alter myocardial infarct size when administered alone. L-NAME, but not 7-NI or AG, abolished helium-induced cardioprotection. Helium enhanced DAF-2DA fluorescence compared with control (26 ± 8 vs 15 ± 5 U, respectively). Pretreatment with L-NAME abolished these helium-induced increases in DAF-2DA fluorescence. CONCLUSIONS The results indicate that cardioprotection by helium is mediated by NO that is probably generated by endothelial NOS in vivo. PMID:18713880

  17. Nitric oxide in central amygdala potentiates expression of conditioned withdrawal induced by morphine

    PubMed Central

    Karami, Manizheh; Rahimpour, Mahnaz; Karimi, Sara; Sahraei, Hedayat

    2014-01-01

    Objective: The aim of this study was to evaluate if nitric oxide (NO) in the central amygdala (CeA) is involved in the expression of withdrawal aspects induced by morphine. Materials and Methods: Male Wistar rats (weighing 200-250 g) were bilaterally cannulated in the CeA and conditioned to morphine using an unbiased paradigm. Morphine (2.5-10 mg/kg) was subcutaneously injected once a day throughout the conditioning phase of the procedure. This phase also included 3-saline paired sessions. Naloxone (0.1-0.4 mg/kg, intraperitoneally [i.p.]), an antagonist of opioid receptors, was administered i.p. 10 min prior to testing of morphine-induced withdrawal features. The NO precursor, L-arginine (0.3-3 ?g/rat) was intra-CeA injected prior to testing of naloxone response. To evaluate the involvement of NO system an inhibitor of NO synthase (NOS), NG-nitro-L-arginine methyl ester (L-NAME) (0.3-3 ?g/rat), was injected ahead of L-arginine. Control group received saline solely instead of drug. As a complementary study, the activation of NOS was studied by nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d). Results: Morphine induced a significant increase in wet dog shaking and grooming behaviors compared with controls. Injection of naloxone pre-testing of morphine response significantly reversed the response to morphine. However, pre-microinjection of L-arginine intra-CeA recovered the response to morphine. Injection of L-NAME intra-CeA ahead of L-arginine though had no effect behaviorally, but, inhibited the NOS which has been evidenced by NADPH-d. Conclusion: The present study shows that NO in the CeA potentiates the expression of conditioned withdrawal induced by morphine paired with naloxone. PMID:24550586

  18. Nitric Oxide-Induced p53 Accumulation and Regulation of Inducible Nitric Oxide Synthase Expression by Wild-Type p53

    Microsoft Academic Search

    Kathleen Forrester; Stefan Ambs; Shawn E. Lupold; Rachel B. Kapust; Elisa A. Spillare; Wendy C. Weinberg; Emanuela Felley-Bosco; Xin W. Wang; David A. Geller; Edith Tzeng; Timothy R. Billiar; Curtis C. Harris

    1996-01-01

    The tumor suppressor gene product p53 plays an important role in the cellular response to DNA damage from exogenous chemical and physical mutagens. Therefore, we hypothesized that p53 performs a similar role in response to putative endogenous mutagens, such as nitric oxide (NO). We report here that exposure of human cells to NO generated from an NO donor or from

  19. Convergence of Nitric Oxide and Lipid Signaling: Anti-Inflammatory Nitro-Fatty Acids

    PubMed Central

    Baker, Paul R.S.; Schopfer, Francisco J.; O’Donnell, Valerie B.; Freeman, Bruce A.

    2009-01-01

    The signaling mediators nitric oxide (·NO) and oxidized lipids, once viewed to transduce metabolic and inflammatory information via discrete and independent pathways, are now appreciated as interdependent regulators of immune response and metabolic homeostasis. The interactions between these two classes of mediators result in reciprocal control of mediator sythesis that is strongly influenced by the local chemical environment. The relationship between the two pathways extends beyond co-regulation of ·NO and eicosanoid formation to converge via the nitration of unsaturated fatty acids to yield nitro derivatives (NO2-FA). These pluripotent signaling molecules are generated in vivo as an adaptive response to oxidative inflammatory conditions and manifest predominantly anti-inflammatory signaling reactions. These actions of NO2-FA are diverse, with these species serving as a potential chemical reserve of ·NO, reacting with cellular nucleophiles to post-translationally modify protein structure, function and localization. In this regard these species act as potent endogenous ligands for peroxisome proliferator activated receptor ?. Functional consequences of these signaling mechanisms have been shown in multiple model systems, including the inhibition of platelet and neutrophil functions, induction of heme oxygenase-1, inhibition of LPS-induced cytokine release in monocytes, increased insulin sensitivity and glucose uptake in adipocytes and relaxation of pre-constricted rat aortic segments. These observations have propelled further in vitro and in vivo studies of mechanisms of NO2-FA signaling and metabolism, highlighting the therapeutic potential of this class of molecules as anti-inflammatory drug candidates. PMID:19200454

  20. New inhibitors of nitric oxide production from the seeds of Myristica fragrans.

    PubMed

    Cao, Gui-Yun; Yang, Xiu-Wei; Xu, Wei; Li, Fei

    2013-12-01

    Six dihydrobenzofuran type neolignans were isolated from the dried ripe seeds of Myristica fragrans Houtt. (family: Myristicaceae) and their chemical structures were identified as licarin B (1), 3'-methoxylicarin B (2), myrisfrageal A (3), isodihydrocainatidin (4), dehydrodiisoeugenol (5), and myrisfrageal B (6), respectively, on the basis of spectroscopic data analyses. Among them, compounds 3 and 6 are new compounds. Compounds 1-6 showed inhibition of nitric oxide production in lipopolysaccharide-activated murine monocyte-macrophage RAW264.7 with IC50 values of 53.6, 48.7, 76.0, 36.0, 33.6, and 45.0 ?M, respectively. These values were compared to those of the positive controls, indomethacin and L-N(6)-(1-iminoethyl)-lysine, which have IC50 values of 65.3 and 27.1 ?M, respectively. Further compounds 3, 5 and 6 suppressed LPS-induced iNOS mRNA expression in a does-dependent manner in RAW 264.7 cells assayed by real-time RT-PCR. Compounds 3, 5 and 6 may inhibit NO overproduction via inhibition of iNOS mRNA expression. The results provided valuable information for further investigation of compounds 1-6 as anti-inflammatory and chemopreventive agents. PMID:23994084

  1. YC-1 potentiates cAMP-induced CREB activation and nitric oxide production in alveolar macrophages

    SciTech Connect

    Hwang, Tsong-Long, E-mail: htl@mail.cgu.edu.tw [Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Taoyuan, Taiwan (China) [Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Taoyuan, Taiwan (China); Chinese Herbal Medicine Research Team, Healthy Aging Research Center, Chang Gung University, Kweishan, Taoyuan, Taiwan (China); Tang, Ming-Chi [Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Taoyuan, Taiwan (China)] [Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Taoyuan, Taiwan (China); Kuo, Liang-Mou [Department of General Surgery, Chang Gung Memorial Hospital at Chia-Yi, Taiwan (China)] [Department of General Surgery, Chang Gung Memorial Hospital at Chia-Yi, Taiwan (China); Chang, Wen-De; Chung, Pei-Jen; Chang, Ya-Wen; Fang, Yao-Ching [Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Taoyuan, Taiwan (China)] [Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Taoyuan, Taiwan (China)

    2012-04-15

    Alveolar macrophages play significant roles in the pathogenesis of several inflammatory lung diseases. Increases in exhaled nitric oxide (NO) are well documented to reflect disease severity in the airway. In this study, we investigated the effect of 3-(5?-hydroxymethyl-2?-furyl)-1-benzyl indazole (YC-1), a known activator of soluble guanylyl cyclase, on prostaglandin (PG)E{sub 1} (a stable PGE{sub 2} analogue) and forskolin (a adenylate cyclase activator) induced NO production and inducible NO synthase (iNOS) expression in rat alveolar macrophages (NR8383). YC-1 did not directly cause NO production or iNOS expression, but drastically potentiated PGE{sub 1}- or forskolin-induced NO production and iNOS expression in NR8383 alveolar macrophages. Combination treatment with YC-1 and PGE{sub 1} significantly increased phosphorylation of the cAMP response element-binding protein (CREB), but not nuclear factor (NF)-?B activation. The combined effect on NO production, iNOS expression, and CREB phosphorylation was reversed by a protein kinase (PK)A inhibitor (H89), suggesting that the potentiating functions were mediated through a cAMP/PKA signaling pathway. Consistent with this, cAMP analogues, but not the cGMP analogue, caused NO release, iNOS expression, and CREB activation. YC-1 treatment induced an increase in PGE{sub 1}-induced cAMP formation, which occurred through the inhibition of cAMP-specific phosphodiesterase (PDE) activity. Furthermore, the combination of rolipram (an inhibitor of PDE4), but not milronone (an inhibitor of PDE3), and PGE{sub 1} also triggered NO production and iNOS expression. In summary, YC-1 potentiates PGE{sub 1}-induced NO production and iNOS expression in alveolar macrophages through inhibition of cAMP PDE activity and activation of the cAMP/PKA/CREB signaling pathway. Highlights: ? YC-1 potentiated PGE1-induced iNOS expression in alveolar macrophages. ? The combination of YC-1 and PGE1 increased CREB but not NF?B activation. ? The combined effects were reversed by H89. ? The combination of rolipram and PGE1 triggered NO production and iNOS expression. ? Effect of YC-1 occurred through inhibition of cAMP-specific PDE.

  2. Involvement of nitric oxide in iodine deficiency-induced microvascular remodeling in the thyroid gland: role of nitric oxide synthase 3 and ryanodine receptors.

    PubMed

    Craps, J; Wilvers, C; Joris, V; De Jongh, B; Vanderstraeten, J; Lobysheva, I; Balligand, J-L; Sonveaux, P; Gilon, P; Many, M-C; Gérard, A-C; Colin, I M

    2015-02-01

    Iodine deficiency (ID) induces microvascular changes in the thyroid gland via a TSH-independent reactive oxygen species-hypoxia inducible factor (HIF)-1?-vascular endothelial growth factor (VEGF) pathway. The involvement of nitric oxide (NO) in this pathway and the role of calcium (Ca(2+)) and of ryanodine receptors (RYRs) in NO synthase 3 (NOS3) activation were investigated in a murine model of goitrogenesis and in 3 in vitro models of ID, including primary cultures of human thyrocytes. ID activated NOS3 and the production of NO in thyrocytes in vitro and increased the thyroid blood flow in vivo. Using bevacizumab (a blocking antibody against VEGF-A) in mice, it appeared that NOS3 is activated upstream of VEGF-A. L-nitroarginine methyl ester (a NOS inhibitor) blocked the ID-induced increase in thyroid blood flow in vivo and NO production in vitro, as well as ID-induced VEGF-A mRNA and HIF-1? expression in vitro, whereas S-nitroso-acetyl-penicillamine (a NO donor) did the opposite. Ca(2+) is involved in this pathway as intracellular Ca(2+) flux increased after ID, and thapsigargin activated NOS3 and increased VEGF-A mRNA expression. Two of the 3 known mammalian RYR isoforms (RYR1 and RYR2) were shown to be expressed in thyrocytes. RYR inhibition using ryanodine at 10?M decreased ID-induced NOS3 activation, HIF-1?, and VEGF-A expression, whereas RYR activation with ryanodine at 1nM increased NOS3 activation and VEGF-A mRNA expression. In conclusion, during the early phase of TSH-independent ID-induced microvascular activation, ID sequentially activates RYRs and NOS3, thereby supporting ID-induced activation of the NO/HIF-1?/VEGF-A pathway in thyrocytes. PMID:25406019

  3. Endotoxin-induced ileal Vo 2Do 2 alterations do not correlate with the severity of ileal injury

    Microsoft Academic Search

    Elliott D. Crouser; Mark W. Julian; Steven E. Weisbrode; Paul M. Dorinsky

    1997-01-01

    Purpose: Altered Vo2-Do2 relationships are most often noted to occur in the setting of sepsis or endotoxin (LPS)-induced systemic organ microvascular injury and are generally thought to be causally linked to that injury. However, we have recently shown that ileal microvascular injury is not associated with altered ileal Vo2-Do2 relationships. Thus, we hypothesized that the severity of LPS-induced systemic organ

  4. Retinoic acid attenuates lipopolysaccharide-induced inflammatory responses by suppressing TLR4\\/NF-?B expression in rat mammary tissue

    Microsoft Academic Search

    Beibei Gu; Jinfeng Miao; Yanmei Fa; Jingye Lu; Sixiang Zou

    2010-01-01

    The retinoids, a group of natural or synthetic derivatives of vitamin A, exert various anti-neoplastic and immunomodulatory actions. Recent studies have demonstrated that retinoic acid protects rats against lipopolysaccharide (LPS)-induced mastitis, but the mechanism of action is unclear. In the present study, an LPS-induced rat mastitis model and primary cultures of rat mammary epithelial cells were used to investigate the

  5. Pivotal Role of Reactive Oxygen Species in Differential Regulation of Lipopolysaccharide-Induced Prostaglandins Production in Macrophages

    PubMed Central

    Zhao, Guiqing; Yu, Rui; Deng, Jing; Zhao, Qiong; Li, Yongchao; Joo, Myungsoo; van Breemen, Richard B.; Christman, John W.

    2013-01-01

    Gram-negative bacterial endotoxin lipopolysaccharide (LPS) triggers the production of inflammatory cytokines, reactive oxygen species (ROS), and prostaglandins (PGs) by pulmonary macrophages. Here, we investigated if ROS influenced PGs production in response to LPS treatment in mouse bone marrow-derived macrophages (BMDM). We observed that pretreatment of BMDM with two structurally unrelated ROS scavengers, MnTMPyP and EUK-134, not only prevented LPS-induced ROS accumulation, but also attenuated the LPS-induced PGD2, but not PGE2, production. Conversely LPS-induced PGD2, but not PGE2, production, was potentiated with the cotreatment of BMDM with H2O2. These data suggest that ROS differentially regulate PGD2 and PGE2 production in BMDM. In addition, selective inhibition of the ROS generator NADPH oxidase (NOX) using either pharmacologic inhibitors or its p47phox subunit deficient mouse BMDM also attenuated LPS-induced PGD2, but not PGE2 production, suggesting the critical role of NOX-generated ROS in LPS-induced PGD2 production in BMDM. We further found that both hematopoietic PGD synthase (H-PGDS) siRNA and its inhibitor HQL-79, but not lipocalin PGDS (L-PGDS) siRNA and its inhibitor AT-56, significantly attenuated LPS-induced PGD2 production, suggesting that H-PGDS, but not L-PGDS, mediates LPS-induced PGD2 production in BMDM. Furthermore, data from our in vitro cell-free enzymatic studies showed that coincubation of the recombinant H-PGDS with either MnTMPyP, EUK-134, or catalase significantly decreased PGD2 production, whereas coincubation with H2O2 significantly increased PGD2 production. Taken together, our results show that LPS-induced NOX-generated ROS production differentially and specifically regulates the H-PGDS-mediated production of PGD2, but not PGE2, in mouse BMDM. PMID:23071105

  6. Pivotal role of reactive oxygen species in differential regulation of lipopolysaccharide-induced prostaglandins production in macrophages.

    PubMed

    Zhao, Guiqing; Yu, Rui; Deng, Jing; Zhao, Qiong; Li, Yongchao; Joo, Myungsoo; van Breemen, Richard B; Christman, John W; Xiao, Lei

    2013-01-01

    Gram-negative bacterial endotoxin lipopolysaccharide (LPS) triggers the production of inflammatory cytokines, reactive oxygen species (ROS), and prostaglandins (PGs) by pulmonary macrophages. Here, we investigated if ROS influenced PGs production in response to LPS treatment in mouse bone marrow-derived macrophages (BMDM). We observed that pretreatment of BMDM with two structurally unrelated ROS scavengers, MnTMPyP and EUK-134, not only prevented LPS-induced ROS accumulation, but also attenuated the LPS-induced PGD(2), but not PGE(2), production. Conversely LPS-induced PGD(2), but not PGE(2), production, was potentiated with the cotreatment of BMDM with H(2)O(2). These data suggest that ROS differentially regulate PGD(2) and PGE(2) production in BMDM. In addition, selective inhibition of the ROS generator NADPH oxidase (NOX) using either pharmacologic inhibitors or its p47(phox) subunit deficient mouse BMDM also attenuated LPS-induced PGD(2), but not PGE(2) production, suggesting the critical role of NOX-generated ROS in LPS-induced PGD(2) production in BMDM. We further found that both hematopoietic PGD synthase (H-PGDS) siRNA and its inhibitor HQL-79, but not lipocalin PGDS (L-PGDS) siRNA and its inhibitor AT-56, significantly attenuated LPS-induced PGD(2) production, suggesting that H-PGDS, but not L-PGDS, mediates LPS-induced PGD(2) production in BMDM. Furthermore, data from our in vitro cell-free enzymatic studies showed that coincubation of the recombinant H-PGDS with either MnTMPyP, EUK-134, or catalase significantly decreased PGD(2) production, whereas coincubation with H(2)O(2) significantly increased PGD(2) production. Taken together, our results show that LPS-induced NOX-generated ROS production differentially and specifically regulates the H-PGDS-mediated production of PGD(2), but not PGE(2), in mouse BMDM. PMID:23071105

  7. IL18-deficient mice are resistant to endotoxin-induced liver injury but highly susceptible to endotoxin shock

    Microsoft Academic Search

    Yoshimitsu Sakao; Kiyoshi Takeda; Hiroko Tsutsui; Tsuneyasu Kaisho; Fumiko Nomura; Haruki Okamura; Kenji Nakanishi; Shizuo Akira

    1999-01-01

    IL-18 is an IL-1-related cytokine which shares biological functions with IL-12. These include the activation of NK cells, induction of IFN-g production and Th1 cell differentiation. In this study we analyzed the effect of IL-18 deficiency on lipopolysaccharide (LPS)-induced liver injury and endotoxin shock in Propionibacterium acnes-primed mice. P. acnes-primed IL-18-deficient (IL-18KO) mice showed resistance to LPS-induced liver injury. Unexpectedly,

  8. Role of NPR-C natriuretic receptor in nitric oxide system activation induced by atrial natriuretic peptide

    Microsoft Academic Search

    Rosana Elesgaray; Ana María Balaszczuk; Cristina Arranz

    2006-01-01

    Atrial natriuretic peptide (ANP) exerts its hypotensive, natriuretic and diuretic effects, almost in part, through the activation of nitric oxide synthase (NOS). The aim was to investigate the natriuretic receptor type and the signaling cascade involved in NOS activation induced by ANP. Male Wistar rats were sacrificed and NOS activity was determined in kidney, aorta and heart with l-[U14C]-arginine, as

  9. Altered regulation of renal nitric oxide and atrial natriuretic peptide systems in angiotensin II-induced hypertension

    Microsoft Academic Search

    Eun Hui Bae; Seong Kwon Ma; JongUn Lee; Soo Wan Kim

    2011-01-01

    The present study was aimed to determine whether there is an altered role of local nitric oxide (NO) and atrial natriuretic peptide (ANP) systems in the kidney in association with the angiotensin (Ang) II-induced hypertension. Male Sprague–Dawley rats were used. Ang II (100ng·min?1·kg?1) was infused through entire time course. Thirteenth day after beginning the regimen, kidneys were taken. The protein

  10. Involvement of androgen receptor in nitric oxide production induced by icariin in human umbilical vein endothelial cells

    Microsoft Academic Search

    Hideki Koizumi; Jing Yu; Ryo Hashimoto; Yasuyoshi Ouchi; Tetsuro Okabe

    2010-01-01

    Icariin, a flavonoid isolated from Epimedii herba, stimulated phosphorylation of endothelial nitric oxide synthase (eNOS) at Ser1177, Akt (Ser473) and ERK1\\/2 (Thr202\\/Tyr204). The icariin-induced eNOS phosphorylation was abolished by an androgen receptor (AR) antagonist, nilutamide in human umbilical vein endothelial cells (HUVECs). Furthermore, it was also reduced in the cells transfected with small interfering RNA in which the expression of

  11. Role of inducible nitric oxide synthase in induction of RhoA expression in hearts from diabetic rats<