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Sample records for bradykinin b1 receptor

  1. B1 bradykinin receptors and sensory neurones.

    PubMed Central

    Davis, C. L.; Naeem, S.; Phagoo, S. B.; Campbell, E. A.; Urban, L.; Burgess, G. M.

    1996-01-01

    1. The location of the B1 bradykinin receptors involved in inflammatory hyperalgesia was investigated. 2. No specific binding of the B1 bradykinin receptor ligand [3H]-des-Arg10-kallidin was detected in primary cultures of rat dorsal root ganglion neurones, even after treatment with interleukin-1 beta (100 iu ml-1). 3. In dorsal root ganglion neurones, activation of B2 bradykinin receptors stimulated polyphosphoinositidase C. In contrast, B1 bradykinin receptor agonists (des-Arg9-bradykinin up to 10 microM and des-Arg10-kallidin up to 1 microM) failed to activate polyphosphoinositidase C, even in neurones that had been treated with interleukin-1 beta (100 iu ml-1), prostaglandin E2 (1 microM) or prostaglandin I2 (1 microM). 4. Dorsal root ganglion neurones removed from rats (both neonatal and 14 days old) that had been pretreated with inflammatory mediators (Freund's complete adjuvant, or carrageenan) failed to respond to B1 bradykinin receptor selective agonists (des-Arg9-bradykinin up to 10 microM and des-Arg10-kallidin up to 1 microM). 5. Bradykinin (25 nM to 300 nM) evoked ventral root responses when applied to peripheral receptive fields or central terminals of primary afferents in the neonatal rat spinal cord and tail preparation. In contrast, des-Arg9-bradykinin (50 nM to 500 nM) failed to evoke ventral root depolarizations in either control rats or in animals that developed inflammation following ultraviolet irradiation of the tail skin. 6. The results of the present study imply that the B1 bradykinin receptors that contribute to hypersensitivity in models of persistent inflammatory hyperalgesia are located on cells other than sensory neurones where they may be responsible for releasing mediators that sensitize or activate the nociceptors. PMID:8832074

  2. Synthesis and biological evaluation of bradykinin B(1)/B(2) and selective B(1) receptor antagonists.

    PubMed

    Amblard, M; Bedos, P; Olivier, C; Daffix, I; Luccarini, J M; Dodey, P; Pruneau, D; Paquet, J L; Martinez, J

    2000-06-15

    We recently described a potent bradykinin B(2) receptor agonist (JMV1116) obtained by replacing the D-Tic-Oic dipeptide moiety of HOE140 by a (3S)-amino-5-(carbonylmethyl)-2,3-dihydro-1, 5-benzothiazepin-4(5H)-one (D-BT) moiety. This compound inhibited the specific binding of [(3)H]BK on membranes of CHO cells expressing the human cloned B(2) receptor with nanomolar affinity and contracted both isolated rat uterus and human umbilical vein. These data demonstrated that D-BT could be a good mimic of the Pro-Phe dipeptide. In the present study we characterized B(1) receptor antagonists containing the D-BT moiety. We prepared an analogue of compound JMV1116 deleting the C-terminal arginine residue. The resulting compound (1) had an affinity of 83 nM for the human cloned B(1) receptor. The most remarkable property of 1 is its ability to bind also the B(2) receptor with an affinity of 4.4 nM despite the absence of the C-terminal arginine residue. Modifications at the N-terminal part of 1 associated with the substitution of the thienylalanine residue by alpha-(2-indanyl)glycine resulted in analogues selectively binding to the B(1) receptor with an affinity in the picomolar range.

  3. A rational approach to the design and synthesis of a new bradykinin B(1) receptor antagonist.

    PubMed

    Bedos, P; Amblard, M; Subra, G; Dodey, P; Luccarini, J M; Paquet, J L; Pruneau, D; Aumelas, A; Martinez, J

    2000-06-15

    We have previously synthesized a potent and selective B(1) bradykinin receptor antagonist, JMV1645 (H-Lys-Arg-Pro-Hyp-Gly-Igl-Ser-D-BT-OH), containing a dipeptide mimetic ((3S)-amino-5-carbonylmethyl-2,3-dihydro-1, 5-benzothiazepin-4(5H)-one (D-BT) moiety) at the C-terminal. Analogues of this potent B(1) bradykinin receptor antagonist in which the central Pro(2)-Hyp(3)-Gly(4)-Igl(5) tetrapeptide has been replaced by constrained N-1-substituted-1,3,8-triazaspiro¿4. 5decan-4-one ring system were synthesized. Among these analogues, compound JMV1640 (1) was found to have an affinity of 24.10 +/- 9.48 nM for the human cloned B(1) receptor. It antagonized the ¿des-Arg(10)-kallidin-induced contraction of the human umbilical vein (pA(2) = 6.1 +/- 0.1). Compound 1 was devoid of agonist activity at the kinin B(1) receptor. Moreover, it did not bind to the human cloned B(2) receptor. Therefore, JMV1640 constitutes a lead compound for the rational search of nonpeptide B(1) receptor analogues based on the BK sequence.

  4. Inhibition of RNA synthesis by bradykinin involves both the B1 and B2 receptor subtypes.

    PubMed

    Yau, L; Pinsk, M; Zahradka, P

    1996-04-01

    The efficacy of angiotensin converting enzyme inhibitors in the treatment of heart disease is due in part to the accumulation of bradykinin (BK). Since BK can exert its effect by influencing cell proliferation, we chose to study the effect of BK on the growth of A10 vascular smooth muscle cells. Ligand binding studies to determine which BK receptor subtypes are present on A10 cells showed that both B1 and B2 receptors were present in approximately equal numbers. Examination of RNA synthesis demonstrated that BK inhibits uridine incorporation in a dose-dependent manner. This decrease in RNA synthesis was blocked by both B1 and B2 receptor antagonists, as well as by addition of indomethacin, a cyclooxygenase inhibitor. The latter result suggested that prostaglandins mediate the biological actions of BK. Consequently, we examined the direct effect of two prostaglandins, PGE2 and PGI2 (prostacyclin), on A10 cells. PGE2 caused a decrease in RNA synthesis, thus mimicking the effect of BK, while PGI2 did not. Therefore, the inhibition of RNA synthesis in A10 vascular smooth muscle cells by BK requires both B1 and B2 receptor subtypes and this action of BK is apparently mediated by de novo synthesis of prostaglandins.

  5. Blockade of hippocampal bradykinin B1 receptors improves spatial learning and memory deficits in middle-aged rats.

    PubMed

    Bitencourt, Rafael M; Guerra de Souza, Ana C; Bicca, Maíra A; Pamplona, Fabrício A; de Mello, Nelson; Passos, Giselle F; Medeiros, Rodrigo; Takahashi, Reinaldo N; Calixto, João B; Prediger, Rui D

    2017-01-01

    Previous studies have demonstrated that targeting bradykinin receptors is a promising strategy to counteract the cognitive impairment related with aging and Alzheimer's disease (AD). The hippocampus is critical for cognition, and abnormalities in this brain region are linked to the decline in mental ability. Nevertheless, the impact of bradykinin signaling on hippocampal function is unknown. Therefore, we sought to determine the role of hippocampal bradykinin receptors B1R and B2R on the cognitive decline of middle-aged rats. Twelve-month-old rats exhibited impaired ability to acquire and retrieve spatial information in the Morris water maze task. A single intra-hippocampal injection of the selective B1R antagonist des-Arg(9)-[Leu(8)]-bradykinin (DALBK, 3 nmol), but not the selective B2R antagonist D-Arg-[Hyp(3),Thi(5),D-Tic(7),Oic(8)]-BK (Hoe 140, 3 nmol), reversed the spatial learning and memory deficits on these animals. However, both drugs did not affect the cognitive function in 3-month-old rats, suggesting absence of nootropic properties. Molecular biology analysis revealed an up-regulation of B1R expression in the hippocampal CA1 sub-region and in the pre-frontal cortex of 12-month-old rats, whereas no changes in the B2R expression were observed in middle-aged rats. These findings provide new evidence that inappropriate hippocampal B1R expression and activation exert a critical role on the spatial learning and memory deficits in middle-aged rats. Therefore, selective B1R antagonists, especially orally active non-peptide antagonists, may represent drugs of potential interest to counteract the age-related cognitive decline.

  6. Identification of a nonpeptidic and conformationally restricted bradykinin B1 receptor antagonist with anti-inflammatory activity.

    PubMed

    D'Amico, Derin C; Aya, Toshi; Human, Jason; Fotsch, Christopher; Chen, Jian Jeffrey; Biswas, Kaustav; Riahi, Bobby; Norman, Mark H; Willoughby, Christopher A; Hungate, Randall; Reider, Paul J; Biddlecome, Gloria; Lester-Zeiner, Dianna; Staden, Carlo Van; Johnson, Eileen; Kamassah, Augustus; Arik, Leyla; Wang, Judy; Viswanadhan, Vellarkad N; Groneberg, Robert D; Zhan, James; Suzuki, Hideo; Toro, Andras; Mareska, David A; Clarke, David E; Harvey, Darren M; Burgess, Laurence E; Laird, Ellen R; Askew, Benny; Ng, Gordon

    2007-02-22

    We report the discovery of chroman 28, a potent and selective antagonist of human, nonhuman primate, rat, and rabbit bradykinin B1 receptors (0.4-17 nM). At 90 mg/kg s.c., 28 decreased plasma extravasation in two rodent models of inflammation. A novel method to calculate entropy is introduced and ascribed approximately 30% of the gained affinity between "flexible" 4 (Ki = 132 nM) and "rigid" 28 (Ki = 0.77 nM) to decreased conformational entropy.

  7. Design, synthesis and evaluation of (18)F-labeled bradykinin B1 receptor-targeting small molecules for PET imaging.

    PubMed

    Zhang, Zhengxing; Kuo, Hsiou-Ting; Lau, Joseph; Jenni, Silvia; Zhang, Chengcheng; Zeisler, Jutta; Bénard, François; Lin, Kuo-Shyan

    2016-08-15

    Two fluorine-18 ((18)F) labeled bradykinin B1 receptor (B1R)-targeting small molecules, (18)F-Z02035 and (18)F-Z02165, were synthesized and evaluated for imaging with positron emission tomography (PET). Z02035 and Z02165 were derived from potent antagonists, and showed high binding affinity (0.93±0.44 and 2.80±0.50nM, respectively) to B1R. (18)F-Z02035 and (18)F-Z02165 were prepared by coupling 2-[(18)F]fluoroethyl tosylate with their respective precursors, and were obtained in 10±5 (n=4) and 22±14% (n=3), respectively, decay-corrected radiochemical yield with >99% radiochemical purity. (18)F-Z02035 and (18)F-Z02165 exhibited moderate lipophilicity (LogD7.4=1.10 and 0.59, respectively), and were stable in mouse plasma. PET imaging and biodistribution studies in mice showed that both tracers enabled visualization of the B1R-positive HEK293T::hB1R tumor xenografts with better contrast than control B1R-negative HEK293T tumors. Our data indicate that small molecule antagonists can be used as pharmacophores for the design of B1R-targeting PET tracers.

  8. B1 receptor involvement in the effect of bradykinin on venular endothelial cell proliferation and potentiation of FGF-2 effects

    PubMed Central

    Morbidelli, Lucia; Parenti, Astrid; Giovannelli, Lisa; Granger, Harris J; Ledda, Fabrizio; Ziche, Marina

    1998-01-01

    Bradykinin (BK) contributes to the inflammatory response inducing vasodilation of postcapillary venules and has been demonstrated to induce neovascular growth in subcutaneous rat sponges. In this study the ability of BK to stimulate cell growth and migration in cultured endothelium from coronary postcapillary venules (CVEC) has been investigated. [3H]-thymidine incorporation in subconfluent and synchronised CVEC was used to monitor DNA synthesis over 24 h. BK promoted a concentration-dependent increase of DNA synthesis with maximal activity at 100 nM. At this concentration BK also induced 18 fold accumulation of c-Fos protein immunoreactivity in the nucleus within 1 h from peptide exposure. The total number of cells recovered after 48 h exposure to BK was increased in a concentration-dependent manner. Maximal effect was produced by 100 nM concentration of the peptide which produced 50% increase in cell number. The selective B1 receptor agonist Des-Arg9-BK mimicked the proliferative effect of BK, while the B2 receptor agonist kallidin was devoid of any activity. The proliferation induced by BK was abolished in a concentration-dependent manner by the addition of the B1 selective antagonist Des-Arg9-Leu8-BK, while the selective B2 receptor antagonist HOE140 did not modify BK-induced growth. DNA synthesis and growth promoted by a threshold concentration of fibroblast growth factor-2 (FGF-2) (0.25 nM) were potentiated by increasing concentrations of BK and Des-Arg9-BK. Endothelial cell migration assessed by the Boyden Chamber procedure was not promoted by BK or the selective B1 and B2 receptor agonists. These data are the first demonstration that BK promotes growth of endothelial cells from postcapillary venules. The mitogenic activity of BK involves c-Fos expression and potentiates the growth promoting effect of FGF-2. Only the B1 receptor appears to be responsible for the proliferation induced by BK and suggests that this type of receptor might be

  9. Blocking of bradykinin receptor B1 protects from focal closed head injury in mice by reducing axonal damage and astroglia activation.

    PubMed

    Albert-Weissenberger, Christiane; Stetter, Christian; Meuth, Sven G; Göbel, Kerstin; Bader, Michael; Sirén, Anna-Leena; Kleinschnitz, Christoph

    2012-09-01

    The two bradykinin receptors B1R and B2R are central components of the kallikrein-kinin system with different expression kinetics and binding characteristics. Activation of these receptors by kinins triggers inflammatory responses in the target organ and in most situations enhances tissue damage. We could recently show that blocking of B1R, but not B2R, protects from cortical cryolesion by reducing inflammation and edema formation. In the present study, we investigated the role of B1R and B2R in a closed head model of focal traumatic brain injury (TBI; weight drop). Increased expression of B1R in the injured hemispheres of wild-type mice was restricted to the later stages after brain trauma, i.e. day 7 (P<0.05), whereas no significant induction could be observed for the B2R (P>0.05). Mice lacking the B1R, but not the B2R, showed less functional deficits on day 3 (P<0.001) and day 7 (P<0.001) compared with controls. Pharmacological blocking of B1R in wild-type mice had similar effects. Reduced axonal injury and astroglia activation could be identified as underlying mechanisms, while inhibition of B1R had only little influence on the local inflammatory response in this model. Inhibition of B1R may become a novel strategy to counteract trauma-induced neurodegeneration.

  10. Activation of the human keratinocyte B1 bradykinin receptor induces expression and secretion of metalloproteases 2 and 9 by transactivation of epidermal growth factor receptor.

    PubMed

    Matus, Carola E; Ehrenfeld, Pamela; Pavicic, Francisca; González, Carlos B; Concha, Miguel; Bhoola, Kanti D; Burgos, Rafael A; Figueroa, Carlos D

    2016-09-01

    The B1 bradykinin receptor (BDKRB1) is a component of the kinin cascade localized in the human skin. Some of the effects produced by stimulation of BDKRB1 depend on transactivation of epidermal growth factor receptor (EGFR), but the mechanisms involved in this process have not been clarified yet. The primary purpose of this study was to determine the effect of a BDKRB1 agonist on wound healing in a mouse model and the migration and secretion of metalloproteases 2 and 9 from human HaCaT keratinocytes and delineate the signalling pathways that triggered their secretion. Although stimulation of BDKRB1 induces weak chemotactic migration of keratinocytes and wound closure in an in vitro scratch-wound assay, the BDKRB1 agonist improved wound closure in a mouse model. BDKRB1 stimulation triggers synthesis and secretion of both metalloproteases, effects that depend on the activity of EGFR and subsequent phosphorylation of ERK1/2 and p38 mitogen-activated protein kinases and PI3K/Akt. In the mouse model, immunoreactivity for both gelatinases was concentrated around wound borders. EGFR transactivation by BDKRB1 agonist involves Src kinases family and ADAM17. In addition to extracellular matrix degradation, metalloproteases 2 and 9 regulate cell migration and differentiation, cell functions that are associated with the role of BDKRB1 in keratinocyte differentiation. Considering that BDKRB1 is up-regulated by inflammation and/or by cytokines that are abundant in the inflammatory milieu, more stable BDKRB1 agonists may be of therapeutic value to modulate wound healing.

  11. Pronociceptive Actions of Dynorphin via Bradykinin Receptors

    PubMed Central

    Lai, Josephine; Luo, Miaw-chyi; Chen, Qingmin; Porreca, Frank

    2008-01-01

    The endogenous opioid peptide dynorphin A is distinct from other endogenous opioid peptides in having significant neuronal excitatory and neurotoxic effects that are not mediated by opioid receptors. Some of these non-opioid actions of dynorphin contribute to the development of abnormal pain resulting from a number of pathological conditions. Identifying the mechanisms and the sites of action of dynorphin is essential for understanding the pathophysiology of dynorphin and for exploring novel therapeutic targets for pain. This review will discuss the mechanisms that have been proposed and the recent finding that spinal dynorphin may be an endogenous ligand of bradykinin receptors under pathological conditions to promote pain. PMID:18450375

  12. Synthesis and pharmacological evaluation of dimer derivatives of the bradykinin receptor antagonist HOE-140.

    PubMed

    Daffix, I; Amblard, M; Bergé, G; Dodey, P; Pruneau, D; Paquet, J L; Fouchet, C; Franck, R M; Defrêne, E; Luccarini, J M; Bélichard, P; Martinez, J

    1998-07-01

    The synthesis and pharmacological evaluation of dimer derivatives of the C-terminal fragments of the potent bradykinin antagonist HOE-140, linked through their N-termini, were performed. The influence of peptide moiety length was studied using the succinyl moiety as a linker. Our attention focused on the dimer of the C-terminal tetrapeptide of HOE-140 (compound JMV 980), which displayed some inhibiting activity (IC50 = 247 nM) for bradykinin B2 receptors. Unexpectedly, it was orally active in inhibiting bradykinin-induced hypotension in the rat. Based on this tetrapeptide dimer model, we synthesized pseudotetrapeptide dimer bradykinin antagonists 29 and 33, which exhibited high affinity (Ki = 76 and 61 nM, respectively) for the human cloned B2 receptor. In addition, compound 29 inhibited bradykinin-induced contraction of the human umbilical vein giving a pKB value of 6.45. Compounds 29 and 33 were selective toward B2 receptors because they did not bind to the cloned human B1 receptor up to 10 microM.

  13. Regulation of bradykinin B2-receptor expression by oestrogen

    PubMed Central

    Madeddu, Paolo; Emanueli, Costanza; Varoni, Maria Vittoria; Demontis, Maria Piera; Anania, Vittorio; Gorioso, Nicola; Chao, Julie

    1997-01-01

    Tissue kallikrein is overexpressed in the kidney of female rats, this sexual dimorphism being associated with a greater effect of early blockade of bradykinin B2-receptors on female blood pressure phenotype. We evaluated the effect of ovariectomy and oestradiol benzoate (50 μg kg−1 every two days for two weeks) on the vasodepressor response to intra-arterial injection of bradykinin (150–900 ng kg−1) and on the expression of bradykinin B2-receptors.Ovariectomy reduced the magnitude of the vasodepressor response to bradykinin and unmasked a secondary vasopressor effect. Oestrogen replacement restored the vasodepressor response to bradykinin in ovariectomized rats.The vasodepressor responses to sodium nitroprusside (3–18 μg kg−1), acetylcholine (30–600 ng kg−1), desArg9-bradykinin (150–900 ng kg−1) or prostaglandin E2 (30–600 ng kg−1) were significantly reduced by ovariectomy. Oestrogen restored to normal the responses to desArg9-bradykinin, acetylcholine and prostaglandin E2, but not that to sodium nitroprusside.B2-receptor mRNA levels were decreased by ovariectomy in the aorta and kidney and they were restored to normal levels by oestrogen. Neither ovariectomy nor oestradiol affected receptor expression in the heart and uterus.These results indicate that oestrogen regulates B2-receptor gene expression and function. Since kinins exert a cardiovascular protective action, reduction in their vasodilator activity after menopause might contribute to the increased risk of pathological cardiovascular events. Conversely, the cardioprotective effects of oestrogen replacement might be, at least in part, mediated by activation of the kallikrein-kinin system. PMID:9283715

  14. Noradrenaline release from rat sympathetic neurones triggered by activation of B2 bradykinin receptors.

    PubMed

    Boehm, S; Huck, S

    1997-10-01

    1. The role of bradykinin receptors in the regulation of sympathetic transmitter release was investigated in primary cultures of neurones dissociated from superior cervical ganglia of neonatal rats. These cultures were loaded with [3H]-noradrenaline and the outflow of radioactivity was determined under continuous superfusion. 2. Bradykinin (100 nmol l[-1] applied for 10 min) caused a transient increase in tritium outflow that reached a peak within four minutes after the beginning of the application and then declined towards the baseline, despite the continuing presence of the peptide. ATP (100 micromol l[-1]) and nicotine (10 micromol l[-1]) caused elevations in 3H outflow with similar kinetics, whereas outflow remained elevated during a 10 min period of electrical field stimulation (0.5 ms, 50 mA, 50 V cm[-1], 1.0 Hz). 3. When bradykinin was applied for periods of 2 min, the evoked 3H overflow was half-maximal at 12 nmol l(-1) and reached a maximum of 2.3% of cellular radioactivity. The preferential B1 receptor agonist des-Arg9-bradykinin failed to alter 3H outflow. The B2 receptor antagonists, [D-Phe7]-bradykinin (1 micromol l[-1]) and Hoe 140 (10 nmol l[-1]), per se did not alter 3H outflow, but shifted the concentration-response curve for bradykinin-evoked 3H overflow to the right by a factor of 7.9 and 4.3, respectively. 4. Bradykinin-induced overflow was abolished in the absence of extracellular Ca2+ and in the presence of either 1 micromol l(-1) tetrodotoxin or 300 micromol l(-1) Cd2+, as was electrically-induced overflow. Activation of alpha2-adrenoceptors by 1 micromol l(-1) UK 14,304 reduced both bradykinin- and electrically-triggered overflow. The Ca2+-ATPase inhibitor thapsigargin (0.3 micromol l[-1]) failed to alter either type of stimulated overflow. Caffeine (10 mmol l[-1]) enhanced bradykinin-induced overflow, but reduced overflow triggered by electrical field stimulation. 5. Inclusion of Ba2+ (0.1 to 1 mmol l[-1]) in the superfusion medium enhanced

  15. Role of ERK1/2 activation on itch sensation induced by bradykinin B1 activation in inflamed skin

    PubMed Central

    Chen, Yuanzhen; Jiang, Shuyan; Liu, Yuying; Xiong, Jialing; Liang, Jiexian; Ji, Wenjin

    2016-01-01

    It has previously been demonstrated that bradykinin receptor B1 (B1R) agonists evoke an itch-related scratching response in inflamed skin via the B1 receptor; however, the mechanisms responsible for this abnormal itch sensation remain unclear. Therefore, the present study utilized a complete Freund's adjuvant (CFA)-induced mouse model of inflammation to elucidate the mechanisms responsible. Over a period of 30 min, scratching behavior was quantified by the number of hind limb scratches of the area surrounding the drug injection site on the neck. Furthermore, western blot analysis was used to investigate the potential role of extracellular signal-regulated kinase (ERK) 1/2 signaling as a mediator of itch in CFA-treated mice. The results demonstrated that CFA-induced inflammation at the back of the neck is associated with sustained enhancement of ERK1/2 activation in the spinal cord. Moreover, B1R agonist treatment resulted in increased expression of phosphorylated ERK1/2 in the spinal cord, which peaked at 45 min. Consistent with these findings, inhibition of either mitogen-activated protein/ERK kinase or ERK1/2, as well as inhibition of ERK1/2 activation following inflammation, attenuated B1 receptor-mediated scratching responses to a greater extent, as compared with control mice. Collectively, the results of the present study indicated that enhanced and persistent ERK1/2 activation in the spinal cord may be required to induce a scratching response to B1R agonists following CFA-induced inflammation. PMID:27446253

  16. Bradykinin as a pain mediator: receptors are localized to sensory neurons, and antagonists have analgesic actions

    SciTech Connect

    Steranka, L.R.; Manning, D.C.; DeHaas, C.J.; Ferkany, J.W.; Borosky, S.A.; Connor, J.R.; Vavrek, R.J.; Stewart, J.M.; Snyder, S.H.

    1988-05-01

    Autoradiographic studies localize (/sup 3/H)bradykinin receptor binding sites to the substantia gelatinosa, dorsal root, and a subset of small cells in both the dorsal root and trigeminal ganglia of the guinea pig. (/sup 3/H)Bradykinin labeling is also observed over myocardinal/coronary visceral afferent fibers. The localization of (/sup 3/H)bradykinin receptors to nociceptive pathways supports a role for bradykinin in pain mediation. Several bradkykinin antagonists block bradykinin-induced acute vascular pain in the rat. The bradykinin antagonists also relieve bradykinin- and urate-induced hyperalgesia in the rat paw. These results indicate that bradykinin is a physiologic mediator of pain and that bradykinin antagonists have analgesic activity in both acute and chronic pain models.

  17. Autoregulation of bradykinin receptors and bradykinin-induced prostacyclin formation in human fibroblasts.

    PubMed Central

    Roscher, A A; Manganiello, V C; Jelsema, C L; Moss, J

    1984-01-01

    The interaction of bradykinin (BK) with its specific receptors on intact cultured human fibroblasts results in production of prostaglandins, including prostacyclin (PGI2), and accumulation of cyclic AMP. Incubation of cells with 1 microM BK for 5 min at 37 degrees C led to a marked reduction (75-90%) in BK-induced PGI2 release and in total number of [3H]BK-binding sites with no change in dissociation constant (6.1 and 7.6 nM for control and BK-treated cells, respectively). The decrease in receptor number did not result from BK transferred from the first incubation into the binding assay. BK-induced receptor loss was temperature dependent; exposure of cells to BK at 4 degrees C had little or no effect on receptor number. After incubation with BK for approximately equal to 15 min, further incubation in the absence of BK for 30 min at 37 degrees C almost completely restored both receptor number and BK-induced PGI2 release. With more prolonged exposure to BK (greater than 1 h), restoration of receptors was inversely related to the length of exposure and the concentration of BK. Recovery was unaffected by cycloheximide. During prolonged incubation without removal of BK, cells began to recover receptors by 5 h; greater than 99% of the bradykinin initially present disappeared by 3 h. Bacitracin greatly retarded BK disappearance and totally prevented recovery. These observations provide direct evidence that the number of BK receptors on cultured human fibroblasts can be regulated by BK itself. In addition, it appears that BK-degrading systems, by influencing local concentrations of the peptide, may play an important role in the autoregulation of BK receptors. The presence of highly active degradation systems might serve to protect target tissues from developing chronic insensitivity to BK and, perhaps, similar peptides. PMID:6146639

  18. Angiotensin-converting enzyme inhibitors reduce oxidative stress intensity in hyperglicemic conditions in rats independently from bradykinin receptor inhibitors

    PubMed Central

    Mikrut, Kinga; Kupsz, Justyna; Koźlik, Jacek; Krauss, Hanna; Pruszyńska-Oszmałek, Ewa; Gibas-Dorna, Magdalena

    2016-01-01

    Aim To investigate whether bradykinin-independent antioxidative effects of angiotensin-converting enzyme inhibitors (ACEIs) exist in acute hyperglycemia. Methods Male Wistar rats were divided into the normoglycemic group (n = 40) and the hyperglycemic group (n = 40). Hyperglycemia was induced by a single intraperitoneal injection of streptozotocin (STZ, 65 mg/kg body weight) dissolved in 0.1 mol/L citrate buffer (pH 4.5) 72 hours before sacrifice. The normoglycemic group received the same volume of citrate buffer. Each group was divided into five subgroups (n = 8): control group, captopril group, captopril + bradykinin B1 and B2 receptor antagonists group, enalapril group, and enalapril + bradykinin B1 and B2 receptor antagonists group. Captopril, enalapril, B1 and B2 receptor antagonists, or 0.15 mol/L NaCl were given at 2 and 1 hour before sacrifice. Oxidative status was determined by measuring the concentration of malondialdehyde and H2O2, and the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). Results In STZ-induced hyperglycemic rats ACEIs significantly reduced H2O2 and MDA concentration, while they significantly enhanced SOD and GPx activity. The hyperglycemic group treated simultaneously with ACEIs and bradykinin B1 and B2 receptor antagonists showed a significant decrease in H2O2 concentration compared to the control hyperglycemic group. Conclusion These results suggest the existence of additional antioxidative effect of ACEIs in hyperglycemic conditions, which is not related to the bradykinin mediation and the structure of the drug molecule. PMID:27586552

  19. Upregulation of bradykinin receptors is implicated in the pain associated with caerulein-induced acute pancreatitis.

    PubMed

    Takemura, Yoshinori; Furuta, Sadayoshi; Hirayama, Shigeto; Miyashita, Kazuhiko; Imai, Satoshi; Narita, Michiko; Kuzumaki, Naoko; Tsukiyama, Yoshi; Yamazaki, Mitsuaki; Suzuki, Tsutomu; Narita, Minoru

    2011-07-01

    Although the way for pain management associated with acute pancreatitis has been searched for, there are not enough medications available for it. The aim of the present study was to investigate the role of bradykinin (BK) in pain related to acute pancreatitis. After repeated injections of caerulein (50 μg/kg and 6 times), mice showed edema in the pancreas, and blood concentrations of pancreatic enzymes (amylase and lipase) were clearly elevated. A histopathological study demonstrated that caerulein caused tissue damage characterized by edema, acinar cell necrosis, interstitial hemorrhage, and inflammatory cell infiltrates. Furthermore, the mRNA levels of interleukin-1β and monocyte chemotactic protein (MCP)-1 were significantly increased in the pancreas of caerulein-treated mice. The sensitivity of abdominal organs as measured by abdominal balloon distension was enhanced in caerulein-injected mice, suggesting that caerulein caused pancreatic hyperalgesia. Moreover, repeated treatment with caerulein resulted in cutaneous tactile allodynia of the upper abdominal region as demonstrated by the use of von Frey filaments, indicating that caerulein-treated mice exhibited referred pain. Under this condition, the mRNA levels of bradykinin B1 receptor (BKB1R) and bradykinin B2 receptor (BKB2R) were significantly increased in the dorsal root ganglion (DRG). Finally, we found that des-Arg⁹-(Leu⁸)-bradykinin (BKB1R antagonist) and HOE-140 (BKB2R antagonist) attenuated the acute pancreatitis pain-like state in caerulein-treated mice. These findings suggest that the upregulation of BK receptors in the DRG may, at least in part, contribute to the development of the acute pancreatitis pain-like state in mice.

  20. Enhancement of blood-tumor barrier permeability by Sar-[D-Phe8]des-Arg9BK, a metabolically resistant bradykinin B1 agonist, in a rat C6 glioma model

    PubMed Central

    Cardoso, Ronie Cleverson; Lobão-Soares, Bruno; Bianchin, Marino Muxfeldt; Carlotti, Carlos Gilberto; Walz, Roger; Alvarez-Silva, Márcio; Trentin, Andréa Gonçalves; Nicolau, Mauro

    2004-01-01

    Background While it is well known that bradykinin B2 agonists increase plasma protein extravasation (PPE) in brain tumors, the bradykinin B1 agonists tested thus far are unable to produce this effect. Here we examine the effect of the selective B1 agonist bradykinin (BK) Sar-[D-Phe8]des-Arg9BK (SAR), a compound resistant to enzymatic degradation with prolonged activity on PPE in the blood circulation in the C6 rat glioma model. Results SAR administration significantly enhanced PPE in C6 rat brain glioma compared to saline or BK (p < 0.01). Pre-administration of the bradykinin B1 antagonist [Leu8]-des-Arg (100 nmol/Kg) blocked the SAR-induced PPE in the tumor area. Conclusions Our data suggest that the B1 receptor modulates PPE in the blood tumor barrier of C6 glioma. A possible role for the use of SAR in the chemotherapy of gliomas deserves further study. PMID:15458573

  1. Bradykinin promotes Toll like receptor-4 expression in human gingival fibroblasts.

    PubMed

    Gutiérrez-Venegas, Gloria; Arreguín-Cano, Juan Antonio; Hernández-Bermúdez, Cristina

    2012-12-01

    Bacterial infections are a potent mechanism for enzymatic generation of kinins such as bradykinin (BK), a universal mediator for inducing inflammatory reaction by associating with the B2 receptor and stimulating liberation of arachidonic acid and synthesis of prostaglandin E2 (PGE2). In this study we evaluate the role of bradykinin in regulating the expression of TLR4 receptor in human gingival fibroblasts. We examine the ability of bradykinin to modulate inflammatory response of human gingival fibroblasts to Gram-negative components and evaluated the role of Toll-like receptors (TLR)-4 in the co-operation between bradykinin and bacterial pathogens. We show that treatment with bradykinin promotes TLR4 receptor expression in human gingival fibroblasts (HGF) and amplifies inflammatory responses to the bacterial components of Gram-negative bacteria. The TLR4 expression induced by bradykinin was blocked with Hoe 140, a B2R antagonist. When HGF cells were incubated with BK resulted of an increased in cyclooxygenase-2 (COX-2) expression and prostaglandin E2 synthesis. Bradykinin and lipopolysaccharide, a specific TLR4 ligand stimulated COX-2 expression. In other series of experiments we found that ERK, phosphatidylinositol-3 kinase, protein kinase C and NFkB are involved in BK promoted-increased in TLR4 expression. The results demonstrate that bradykinin up-regulates the expression of TLR4 and promotes an additive increase in inflammatory responses to lipopolysaccharides.

  2. Heterodimerization of human apelin and bradykinin 1 receptors: novel signal transduction characteristics.

    PubMed

    Bai, Bo; Liu, Lulu; Zhang, Ning; Wang, Chunmei; Jiang, Yunlu; Chen, Jing

    2014-07-01

    Apelin receptor (APJ) and bradykinin 1 receptor (B1R) are involved in a variety of important physiological processes, which share many similar characteristics in distribution and functions in the cardiovascular system. This study explored the possibility of heterodimerization between APJ and B1R, and investigated the impact of heterodimer on the signal transduction characteristics and the physiological functions in human endothelial cells after stimulation with their agonists. We first identified the endogenous expression of APJ and B1R in HUVECs and their co-localization on HEK293 membrane. The constitutive heterodimerization between the APJ and B1R was then demonstrated by BRET and FRET assays. Stimulation with Apelin-13 and des -Arg(9)-BK enhanced the phosphorylation of eNOS in HUVECs, which could be dampened by the knockdown of APJ or B1R, indicating the co-existence of APJ and B1R is critical for eNOS phosphorylation in HUVECs. Furthermore, APJ/B1R heterodimers were found to enhance the activity of PKC signaling pathway and increase intracellular Ca(2+) concentration in HEK293 cells, which might be the mechanism of APJ/B1R heterodimers promoting the phosphorylation of eNOS and leads to increased Gαq, PKC signal pathway activities and a significant increase in cell proliferation. The results provide a new theoretical and experimental base for revealed intracellular molecular mechanisms of physiological function involved in the APJ and B1R and provide potential new targets for the development of drugs and treating cardiovascular disease.

  3. Glioblastoma-mesenchymal stem cell communication modulates expression patterns of kinin receptors: Possible involvement of bradykinin in information flow.

    PubMed

    Pillat, Micheli M; Oliveira, Mona N; Motaln, Helena; Breznik, Barbara; Glaser, Talita; Lah, Tamara T; Ulrich, Henning

    2016-04-01

    The most aggressive subtype of brain tumors is glioma WHO grade IV, the glioblastoma (GBM). The present work aims to elucidate the role of kinin receptors in interactions between GBM cells and mesenchymal stem cells (MSC). The GBM cell line U87-MG was stably transfected to express dsRed protein, single cell cloned, expanded, and cultured with MSC, both in the direct co-cultures (DC) and indirect co-cultures (IC) at equal cell number ratio for 72 h. Up- and down-regulation of matrix metalloproteases (MMP)-9 expression in U87-MG and MSC cells, respectively, in direct co-culture points to possible MSC participation in tumor invasion. MMP9 expression is in line with significantly increased expression of kinin B1 (B1R) and B2 receptor (B2R) in U87-MG cells and their decreased levels in MSC, as confirmed by quantitative assessment using flow cytometric analysis. Similarly, in indirect cultures (IC), lacking the contact between GBM and MSC cells, an increase of B1 and B2 receptor expression was again noted in U87-MG cells, and no significant changes in kinin receptors in MSC was observed. Functionality of kinin-B1 and B2 receptors was evidenced by stimulation of intracellular calcium fluxes by their respective agonists, des-Arg9-bradykinin (DBK) and bradykinin (BK). Moreover, BK showed a feedback control on kinin receptor expression in mono-cultures, direct and indirect co-cultures. The treatment with BK resulted in down-regulation of B1 and B2 receptors in MSC, with simultaneous up-regulation of these receptors in U87-MG cells, suggesting that functions of BK in information flow between these cells is important for tumor progression and invasion. © 2015 International Society for Advancement of Cytometry.

  4. Kinin-B1 and B2 receptor activity in proliferation and neural phenotype determination of mouse embryonic stem cells.

    PubMed

    Nascimento, Isis C; Glaser, Talita; Nery, Arthur A; Pillat, Micheli M; Pesquero, João B; Ulrich, Henning

    2015-11-01

    The kinins bradykinin and des-arg(9) -bradykinin cleaved from kininogen precursors by kallikreins exert their biological actions by stimulating kinin-B2 and B1 receptors, respectively. In vitro models of neural differentiation such as P19 embryonal carcinoma cells and neural progenitor cells have suggested the involvement of B2 receptors in neural differentiation and phenotype determination; however, the involvement of B1 receptors in these processes has not been established. Here, we show that B1 and B2 receptors are differentially expressed in mouse embryonic E14Tg2A stem cells undergoing neural differentiation. Proliferation and differentiation assays, performed in the presence of receptor subtype-selective agonists and antagonists, revealed that B1 receptor activity is required for the proliferation of embryonic and differentiating cells as well as for neuronal maturation at later stages of differentiation, while the B2 receptor acts on neural phenotype choice, promoting neurogenesis over gliogenesis. Besides the elucidation of bradykinin functions in an in vitro model reflecting early embryogenesis and neurogenesis, this study contributes to the understanding of B1 receptor functions in this process.

  5. Kinin B1 Receptor in Adipocytes Regulates Glucose Tolerance and Predisposition to Obesity

    PubMed Central

    Motta, Fabiana Louise; Fonseca, Raphael Gomes; Alenina, Natalia; Guadagnini, Dioze; Schadock, Ines; Silva, Elton Dias; Torres, Hugo A. M.; dos Santos, Edson Lucas; Castro, Charlles Heldan; D’Almeida, Vânia; Andreotti, Sandra; Campaña, Amanda Baron; Sertié, Rogério A. L.; Saad, Mario J. A.; Lima, Fabio Bessa; Bader, Michael; Pesquero, João Bosco

    2012-01-01

    Background Kinins participate in the pathophysiology of obesity and type 2 diabetes by mechanisms which are not fully understood. Kinin B1 receptor knockout mice (B1−/−) are leaner and exhibit improved insulin sensitivity. Methodology/Principal Findings Here we show that kinin B1 receptors in adipocytes play a role in controlling whole body insulin action and glucose homeostasis. Adipocytes isolated from mouse white adipose tissue (WAT) constitutively express kinin B1 receptors. In these cells, treatment with the B1 receptor agonist des-Arg9-bradykinin improved insulin signaling, GLUT4 translocation, and glucose uptake. Adipocytes from B1−/− mice showed reduced GLUT4 expression and impaired glucose uptake at both basal and insulin-stimulated states. To investigate the consequences of these phenomena to whole body metabolism, we generated mice where the expression of the kinin B1 receptor was limited to cells of the adipose tissue (aP2-B1/B1−/−). Similarly to B1−/− mice, aP2-B1/B1−/− mice were leaner than wild type controls. However, exclusive expression of the kinin B1 receptor in adipose tissue completely rescued the improved systemic insulin sensitivity phenotype of B1−/− mice. Adipose tissue gene expression analysis also revealed that genes involved in insulin signaling were significantly affected by the presence of the kinin B1 receptor in adipose tissue. In agreement, GLUT4 expression and glucose uptake were increased in fat tissue of aP2-B1/B1−/− when compared to B1−/− mice. When subjected to high fat diet, aP2-B1/B1−/− mice gained more weight than B1−/− littermates, becoming as obese as the wild types. Conclusions/Significance Thus, kinin B1 receptor participates in the modulation of insulin action in adipocytes, contributing to systemic insulin sensitivity and predisposition to obesity. PMID:23024762

  6. Bradykinin B2 receptor contributes to the exaggerated muscle mechanoreflex in rats with femoral artery occlusion

    PubMed Central

    Lu, Jian; Xing, Jihong

    2013-01-01

    each group). In contrast, there was no significant difference in B1 receptor expression in both experimental groups, and arterial injection of R-715, a B1 receptors blocker, had no significant effects on RSNA and MAP responses evoked by muscle stretch. Accordingly, results obtained from this study support our hypothesis that heightened kinin B2 receptor expression in the sensory nerves contributes to the exaggerated muscle mechanoreflex in rats with femoral artery occlusion. PMID:23417862

  7. Ranakinestatin-PPF from the Skin Secretion of the Fukien Gold-Striped Pond Frog, Pelophylax plancyi fukienensis: A Prototype of a Novel Class of Bradykinin B2 Receptor Antagonist Peptide from Ranid Frogs

    PubMed Central

    Ma, Jie; Ge, Lilin; Zhang, Yingqi; Duan, Jinao; Shaw, Chris

    2014-01-01

    The defensive skin secretions of many amphibians are a rich source of bradykinins and bradykinin-related peptides (BRPs). Members of this peptide group are also common components of reptile and arthropod venoms due to their multiple biological functions that include induction of pain, effects on many smooth muscle types, and lowering systemic blood pressure. While most BRPs are bradykinin receptor agonists, some have curiously been found to be exquisite antagonists, such as the maximakinin gene-related peptide, kinestatin—a specific bradykinin B2-receptor antagonist from the skin of the giant fire-bellied toad, Bombina maxima. Here, we describe the identification, structural and functional characterization of a heptadecapeptide (DYTIRTRLHQGLSRKIV), named ranakinestatin-PPF, from the skin of the Chinese ranid frog, Pelophylax plancyi fukienensis, representing a prototype of a novel class of bradykinin B2-receptor specific antagonist. Using a preconstricted preparation of rat tail arterial smooth muscle, a single dose of 10−6 M of the peptide effectively inhibited the dose-dependent relaxation effect of bradykinin between 10−11 M and 10−5 M and subsequently, this effect was pharmacologically-characterized using specific bradykinin B1- (desArg-HOE140) and B2-receptor (HOE140) antagonists; the data from which demonstrated that the antagonism of the novel peptide was mediated through B2-receptors. Ranakinestatin—PPF—thus represents a prototype of an amphibian skin peptide family that functions as a bradykinin B2-receptor antagonist herein demonstrated using mammalian vascular smooth muscle. PMID:25161395

  8. Differential Distribution of Bradykinin B(2) Receptors in the Rat and Human Cardiovascular System.

    PubMed

    Figueroa, Carlos D.; Marchant, Alejandra; Novoa, Ulises; Förstermann, Ulrich; Jarnagin, Kurt; Schölkens, Bernward; Müller-Esterl, Werner

    2001-01-01

    -Bradykinin, a major vasodilator peptide, plays an important role in the local regulation of blood pressure, blood flow, and vascular permeability; however, the cellular distribution of the major bradykinin B(2) receptor in the cardiovascular system is not precisely known. Immunoblot analysis with an anti-peptide antibody to the bradykinin B(2) receptor or chemical cross-linkage with [(125)I]Tyr(0)-bradykinin revealed a band of 69+/-3 kDa at varying intensity in the homogenates of the endothelium and tunica media of the rat aorta and endocardium. Immunostaining showed that the B(2) receptor is abundant in the endothelial linings of the aorta, other elastic arteries, muscular arteries, capillaries, venules, and large veins, where it localizes preferentially to the luminal face of the endothelial cells. In marked contrast, small arterioles (ie, the principal blood-pressure regulating vessels) of the mesenterium, heart, urinary bladder, brain, salivary gland, and kidney had a different staining pattern in which B(2) receptor was prominent in the perivascular smooth muscle cells of the tunica media. A similar distribution pattern was found in mouse as well as in human tissues, indicating that the particular distribution pattern of the B(2) receptor in arterioles is not a species-specific phenomenon. During development, the distribution of B(2) receptor in the heart changes; for example, in the heart of newborn rats, the B(2) receptor was abundant in the myocardium, whereas in the adult heart, the receptor was present in the endocardium of atria, atrioventricular valves, and ventricles but not in the myocardium. Thus, B(2) receptors are localized differentially in different parts of the cardiovascular system: the arterioles have smooth muscle-localized B(2) receptors, and large elastic vessels have endothelium-localized receptors.

  9. Synthesis and characterization of bradykinin B(2) receptor agonists containing constrained dipeptide mimics.

    PubMed

    Amblard, M; Daffix, I; Bergé, G; Calmès, M; Dodey, P; Pruneau, D; Paquet, J L; Luccarini, J M; Bélichard, P; Martinez, J

    1999-10-07

    We have previously shown that substitution of the D-Tic-Oic dipeptide by a (3S)-[amino]-5-(carbonylmethyl)-2,3-dihydro-1, 5-benzothiazepin-4(5H)-one (D-BT) moiety in the bradykinin B(2) receptor antagonist HOE 140 resulted in a full potent and selective bradykinin B(2) receptor agonist (H-DArg-Arg-Pro-Hyp-Gly-Thi-Ser-D-BT-Arg-OH, JMV1116) exhibiting a high affinity for the human receptor (K(i) 0.7 nM). In the present study, we have investigated the effects of replacement of the D-Tic-Oic moiety by various constrained dipeptide mimetics. The resulting compounds were tested for their binding affinity toward the cloned human B(2) receptor and for their functional interaction with the bradykinin-induced contraction of isolated human umbilical vein. Subsequently, we have designed novel bradykinin B(2) receptor agonists which are likely to be resistant to enzymatic cleavage by endopeptidases and which might represent interesting new pharmacological tools. In an attempt to increase the potency of compound JMV1116, both its N-terminal part and the D-BT moiety were modified. Substitution of the D-arginine residue by a L-lysine residue led to a 10-fold more potent bradykinin B(2) ligand [compound 22 (JMV1465) (K(i) 0.07 nM)], retaining full agonist activity on human umbilical vein. Substitution of the D-BT moiety by a (3S)-[amino]-5-(carbonylmethyl)-2,3-dihydro-8-methyl-1, 5-benzothiazepin-4(5H)-one [D-BT(Me)] moiety led to compound 23 (JMV1609) which exhibited a higher agonist activity (pD(2) = 7.4) than JMV1116 (pD(2) = 6.8).

  10. New insights into the stereochemical requirements of the bradykinin B2 receptor antagonists binding

    NASA Astrophysics Data System (ADS)

    Lupala, Cecylia S.; Gomez-Gutierrez, Patricia; Perez, Juan J.

    2016-01-01

    Bradykinin (BK) is a member of the kinin family, released in response to inflammation, trauma, burns, shock, allergy and some cardiovascular diseases, provoking vasodilatation and increased vascular permeability among other effects. Their actions are mediated through at least two G-protein coupled receptors, B1 a receptor up-regulated during inflammation episodes or tissue trauma and B2 that is constitutively expressed in a variety of cell types. The goal of the present work is to carry out a structure-activity study of BK B2 antagonism, taking into account the stereochemical features of diverse non-peptide antagonists and the way these features translate into ligand anchoring points to complementary regions of the receptor, through the analysis of the respective ligand-receptor complex. For this purpose an atomistic model of the BK B2 receptor was built by homology modeling and subsequently refined embedded in a lipid bilayer by means of a 600 ns molecular dynamics trajectory. The average structure from the last hundred nanoseconds of the molecular dynamics trajectory was energy minimized and used as model of the receptor for docking studies. For this purpose, a set of compounds with antagonistic profile, covering maximal diversity were selected from the literature. Specifically, the set of compounds include Fasitibant, FR173657, Anatibant, WIN64338, Bradyzide, CHEMBL442294, and JSM10292. Molecules were docked into the BK B2 receptor model and the corresponding complexes analyzed to understand ligand-receptor interactions. The outcome of this study is summarized in a 3D pharmacophore that explains the observed structure-activity results and provides insight into the design of novel molecules with antagonistic profile. To prove the validity of the pharmacophore hypothesized a virtual screening process was also carried out. The pharmacophore was used as query to identify new hits using diverse databases of molecules. The results of this study revealed a set of new

  11. Effects of bradykinin B2 receptor antagonism on the hypotensive effects of ACE inhibition.

    PubMed Central

    Bouaziz, H; Joulin, Y; Safar, M; Benetos, A

    1994-01-01

    1. The aim of this study was to determine the participation of endogenous bradykinin (BK) in the antihypertensive effects of the angiotensin converting enzyme inhibitor (ACEI), perindoprilat, in the spontaneously hypertensive rat (SHR) on different salt diets. 2. Conscious SHRs receiving either a low or a high NaCl diet were used in order to evaluate the respective roles of angiotensin II suppression and bradykinin stimulation in the acute hypotensive effects of perindoprilat. Two different B2 receptor antagonists (B 4146 and Hoe 140) were used after bolus administration of 7 mg kg-1 of the ACEI, perindoprilat. In separate animals, Hoe 140 was administered before the injection of perindoprilat. In other experiments, the effects of Hoe 140 on the hypotensive effects of the calcium antagonist, nicardipine, were tested. 3. The different NaCl diets had no effect on baseline blood pressure. Hoe 140 injection before ACE inhibition did not modify blood pressure. Perindoprilat caused more marked hypotension in the low salt-fed rats than in the high salt animals (P < 0.01). Administration of Hoe 140 or B4146 after perindoprilat significantly reduced the antihypertensive effects of perindoprilat in the different groups, but this effect was more pronounced in high salt-fed rats. However, in SHRs receiving Hoe 140 before perindoprilat, the antihypertensive effect of perindoprilat was completely abolished in both high or low salt diet rats. In separate experiments we confirmed that Hoe 140 did not affect the hypotensive efficacy of the calcium antagonist, nicardipine. 4. Our study shows that inhibition of endogenous bradykinin degradation participates in the acute antihypertensive effects of perindoprilat in SHRs. The role of bradykinin is more pronounced following exposure to a high salt diet i.e., when the renin-angiotensin system is suppressed.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7858859

  12. The transient receptor potential ankyrin-1 mediates mechanical hyperalgesia induced by the activation of B1 receptor in mice.

    PubMed

    Meotti, Flavia Carla; Figueiredo, Cláudia Pinto; Manjavachi, Marianne; Calixto, João B

    2017-02-01

    The kinin receptor B1 and the transient receptor potential ankyrin 1 (TRPA1) work as initiators and gatekeepers of nociception and inflammation. This study reports that the nociceptive transmission induced by activation of B1 receptor is dependent on TRPA1 ion channel. The mechanical hyperalgesia was induced by intrathecal (i.t.) injection of B1 agonist des-Arginine(9)-bradykinin (DABK) or TRPA1 agonist cinnamaldehyde and was evaluated by the withdrawal response after von Frey Hair application in the hind paw. After behavioral experiments, lumbar spinal cord and dorsal root ganglia (DRG) were harvested to assess protein expression and mRNA by immunohistochemistry and real time-PCR, respectively. The pharmacological antagonism (HC030031) or the down-regulation of TRPA1 greatly inhibited the mechanical hyperalgesia induced by DABK. Intrathecal injection of DABK up regulated the ionized calcium binding adaptor molecule (Iba-1) in lumbar spinal cord (L5-L6); TRPA1 protein and mRNA in lumbar spinal cord; and B1 receptor mRNA in both lumbar spinal cord and DRG. The knockdown of TRPA1 prevented microglia activation induced by DABK. Furthermore, the mechanical hyperalgesia induced by either DABK or by cinnamaldehyde was significantly reduced by inhibition of cyclooxygenase (COX), protein kinase C (PKC) or phospholipase C (PLC). In summary, this study revealed that TRPA1 positively modulates the mechanical hyperalgesia induced by B1 receptor activation in the spinal cord and that the classical GPCR downstream molecules PLC, diacylglycerol (DAG), 3,4,5-inositide phosphate (IP3) and PKC are involved in the nociceptive transmission triggered by these two receptors.

  13. Heteromerization Between the Bradykinin B2 Receptor and the Angiotensin-(1-7) Mas Receptor: Functional Consequences.

    PubMed

    Cerrato, Bruno D; Carretero, Oscar A; Janic, Brana; Grecco, Hernán E; Gironacci, Mariela M

    2016-10-01

    Bradykinin B2 receptor (B2R) and angiotensin-(1-7) Mas receptor (MasR)-mediated effects are physiologically interconnected. The molecular basis for such cross talk is unknown. It is hypothesized that the cross talk occurs at the receptor level. We investigated B2R-MasR heteromerization and the functional consequences of such interaction. B2R fused to the cyan fluorescent protein and MasR fused to the yellow fluorescent protein were transiently coexpressed in human embryonic kidney293T cells. Fluorescence resonance energy transfer analysis showed that B2R and MasR formed a constitutive heteromer, which was not modified by their agonists. B2R or MasR antagonists decreased fluorescence resonance energy transfer efficiency, suggesting that the antagonist promoted heteromer dissociation. B2R-MasR heteromerization induced an 8-fold increase in the MasR ligand-binding affinity. On agonist stimulation, the heteromer was internalized into early endosomes with a slower sequestration rate from the plasma membrane, compared with single receptors. B2R-MasR heteromerization induced a greater increase in arachidonic acid release and extracellular signal-regulated kinase phosphorylation after angiotensin-(1-7) stimulation, and this effect was blocked by the B2R antagonist. Concerning serine/threonine kinase Akt activity, a significant bradykinin-promoted activation was detected in B2R-MasR but not in B2R-expressing cells. Angiotensin-(1-7) and bradykinin elicited antiproliferative effects only in cells expressing B2R-MasR heteromers, but not in cells expressing each receptor alone. Proximity ligation assay confirmed B2R-MasR interaction in human glomerular endothelial cells supporting the interaction between both receptors in vivo. Our findings provide an explanation for the cross talk between bradykinin B2R and angiotensin-(1-7) MasR-mediated effects. B2R-MasR heteromerization induces functional changes in the receptor that may lead to long-lasting protective properties.

  14. The effects of bradykinin and sequence-related analogs on the response properties of cutaneous nociceptors in monkeys.

    PubMed

    Khan, A A; Raja, S N; Manning, D C; Campbell, J N; Meyer, R A

    1992-01-01

    The endogenous peptide bradykinin is found in plasma and inflammatory exudates and has been implicated as a chemical mediator of inflammatory pain and hyperalgesia. Two subtypes of bradykinin receptors, B1 and B2, have been described, and antagonists for the receptor subtypes have been synthesized. The bradykinin analogs [desArg9,Leu8]BK and DArg[Hyp3,DPhe7]BK have been reported to have antagonist activity at the B1 and B2 bradykinin receptors in smooth muscle, respectively. Behavioral studies in rats indicate that the bradykinin analogs can block the algesic effects of bradykinin. We wished to determine the effects of bradykinin and the bradykinin analogs (B1 and B2 analogs, respectively) on cutaneous nociceptors in the monkey. In addition, we wished to determine the type of bradykinin receptor that mediates the sensitizing effects of bradykinin. Recordings were made from single C-fiber and A-fiber nociceptive afferents (CMHs and AMHs) that innervated hairy skin. Heat sensitivity before and after the injections was determined with a heat test sequence consisting of stimuli that ranged, in 1 degree C increments, from 41 degrees to 49 degrees C. Intradermal injections of vehicle (neutral normal saline) failed to alter the heat response of CMHs. Bradykinin (10 nmol in 10 microliters) evoked activity in 6 of 10 CMHs and sensitized all the fibers to heat stimuli. After the bradykinin injection, the mean heat threshold of the CMHs decreased from 44 +/- 0.5 degrees to 42.7 +/- 0.5 degrees C (mean +/- SEM, p less than 0.02), and the total response to the heat test sequence increased by 87% (p less than 0.002). In a related psychophysical study in human volunteers, the same dose of bradykinin resulted in a comparable (115%) increase in ratings of pain (Manning et al., 1991). Bradykinin also evoked activity in 10 of 17 AMHs and sensitized 8 AMHs to heat stimuli. Bradykinin failed to alter the threshold for activation of CMHs to mechanical stimuli as measured by application

  15. Bradykinin B2-receptor-mediated modulation of membrane currents in guinea-pig cardiomyocytes

    PubMed Central

    Sakamoto, Naoya; Uemura, Hiroko; Hara, Yukio; Saito, Toshihiro; Masuda, Yoshiaki; Nakaya, Haruaki

    1998-01-01

    In order to define the electrophysiological mechanism(s) responsible for bradykinin (BK)-induced positive inotropic and chronotropic responses in isolated guinea-pig atria, effects of BK on the membrane currents were examined in isolated atrial cells using patch clamp techniques.BK (0.1–1000 nM) increased the L-type Ca2+ current (ICa), which was recorded from enzymatically-dissociated atrial myocytes by the nystatin-perforated patch method, in a concentration-dependent fashion, and the calculated EC50 value for increasing ICa was 5.2 nM. In conventional ruptured patch experiments, BK inhibited the muscarinic acetylcholine receptor-operated K+ current (IK.ACh) that was activated by the muscarinic agonist carbachol (1 μM) with an EC50 value of 0.57 nM. Both the increase in ICa and the decrease in IK.ACh were blocked by HOE140, a selective bradykinin B2 receptor antagonist.The BK-induced inhibition of IK.ACh was significantly attenuated by staurosporine and calphostin C, protein kinase C inhibitors. In addition, the IK.ACh inhibition by BK was also attenuated by the tyrosine kinase inhibitor genistein or tyrphostin but not by daidzein, an inactive analogue of genistein. However, neither protein kinase C inhibitor nor tyrosine kinase inhibitor affected the BK-induced increase in ICa.In the presence and absence of muscarinic stimulation, BK prolonged the action potential recorded from the atrial cells in the current clamp mode.We conclude that BK increases ICa and decreases IK.ACh in atrial cells, resulting in positive inotropic and chronotropic responses in atrial preparations. Protein kinase C activation, and possibly tyrosine kinase activation, may be involved in the B2-receptor-mediated IK.ACh inhibition. PMID:9786500

  16. B-9972 (D-Arg-[Hyp3,Igl5,Oic7,Igl8]-bradykinin) is an inactivation-resistant agonist of the bradykinin B2 receptor derived from the peptide antagonist B-9430 (D-Arg-[Hyp3,Igl5,D-Igl7,Oic8]-bradykinin): pharmacologic profile and effective induction of receptor degradation.

    PubMed

    Bawolak, Marie-Thérèse; Gera, Lajos; Morissette, Guillaume; Stewart, John M; Marceau, François

    2007-11-01

    The bradykinin B(2) receptor is a heptahelical receptor regulated by a cycle of phosphorylation, endocytosis, and extensive recycling at the cell surface following agonist stimulation. B-9430 (d-Arg-[Hyp(3),Igl(5),D-Igl(7),Oic(8)]-bradykinin) is a second generation peptide antagonist found to be competitive at the human B(2) receptor and insurmountable at the rabbit B(2) receptor (contractility assays, isolated human umbilical and rabbit jugular veins). Two isomers of this peptide were prepared: B-10344 (D-Arg-[Hyp(3),Igl(5),Oic(7),D-Igl(8)]-bradykinin; inverted sequence Oic(7), D-Igl(8)) and B-9972 (D-Arg-[Hyp(3),Igl(5),Oic(7),Igl(8)]-bradykinin); they are low- and high-potency agonists, respectively, in vascular preparations. The potency gap between bradykinin and B-9972 is narrow in contractility assays, despite the fact that B-9972 affinity is 7-fold inferior at the rabbit B(2) receptor (radioligand binding competition assay). The effects of agonists on receptors were compared using two chimerical constructions based on rabbit B(2) receptors: conjugate of the B(2) receptor with green fluorescent protein (B(2)R-GFP) and the N-terminally tagged conjugate of the myc epitope with the B(2) receptor. Imaging and immunoblotting showed that B-9972 induced a persistent endocytosis of cell surface B(2) receptors in human embryonic kidney 293 cells with slow receptor degradation (weak after 3 h of treatment, important at 12 h) and B(2)R-GFP desensitization ([(3)H]bradykinin endocytosis and extracellular signal-regulated kinase 1/2 phosphorylation assays). Bradykinin was not active in this respect but when combined with captopril, induced some degradation. B-9430 reduced the endocytosis and degradation of B(2) receptors by the agonists. The results illustrate the agonist-antagonist transition in B(2) receptor peptide ligands with a constrained C-terminal structure, the importance of species in their pharmacological profile, and the possibility of selectively degrading

  17. Bradykinin-induced Ca2+ signaling in human subcutaneous fibroblasts involves ATP release via hemichannels leading to P2Y12 receptors activation

    PubMed Central

    2013-01-01

    Background Chronic musculoskeletal pain involves connective tissue remodeling triggered by inflammatory mediators, such as bradykinin. Fibroblast cells signaling involve changes in intracellular Ca2+ ([Ca2+]i). ATP has been related to connective tissue mechanotransduction, remodeling and chronic inflammatory pain, via P2 purinoceptors activation. Here, we investigated the involvement of ATP in bradykinin-induced Ca2+ signals in human subcutaneous fibroblasts. Results Bradykinin, via B2 receptors, caused an abrupt rise in [Ca2+]i to a peak that declined to a plateau, which concentration remained constant until washout. The plateau phase was absent in Ca2+-free medium; [Ca2+]i signal was substantially reduced after depleting intracellular Ca2+ stores with thapsigargin. Extracellular ATP inactivation with apyrase decreased the [Ca2+]i plateau. Human subcutaneous fibroblasts respond to bradykinin by releasing ATP via connexin and pannexin hemichannels, since blockade of connexins, with 2-octanol or carbenoxolone, and pannexin-1, with 10Panx, attenuated bradykinin-induced [Ca2+]i plateau, whereas inhibitors of vesicular exocytosis, such as brefeldin A and bafilomycin A1, were inactive. The kinetics of extracellular ATP catabolism favors ADP accumulation in human fibroblast cultures. Inhibition of ectonucleotidase activity and, thus, ADP formation from released ATP with POM-1 or by Mg2+ removal from media reduced bradykinin-induced [Ca2+]i plateau. Selective blockade of the ADP-sensitive P2Y12 receptor with AR-C66096 attenuated bradykinin [Ca2+]i plateau, whereas the P2Y1 and P2Y13 receptor antagonists, respectively MRS 2179 and MRS 2211, were inactive. Human fibroblasts exhibited immunoreactivity against connexin-43, pannexin-1 and P2Y12 receptor. Conclusions Bradykinin induces ATP release from human subcutaneous fibroblasts via connexin and pannexin-1-containing hemichannels leading to [Ca2+]i mobilization through the cooperation of B2 and P2Y12 receptors. PMID

  18. Multiple mechanisms in the motor responses of the guinea-pig isolated urinary bladder to bradykinin.

    PubMed Central

    Maggi, C. A.; Patacchini, R.; Santicioli, P.; Geppetti, P.; Cecconi, R.; Giuliani, S.; Meli, A.

    1989-01-01

    1. Bradykinin (1 nm-1 microM) produced a contraction of bladder strips excised from the dome of the guinea-pig urinary bladder, an effect which was greatly enhanced by removal of the mucosal layer or by thiorphan (10 microM). All subsequent experiments were performed in mucosa-free strips and in the presence of thiorphan. 2. In carbachol (5 microM)-contracted strips, bradykinin produced a concentration (1 nm-1 microM)-dependent transient relaxation. 3. Kallidin was slightly more potent than bradykinin in producing a contraction and a relaxation of the carbachol-induced tone. By contrast, [des-Arg9]-bradykinin, a selective B1 receptor agonist was barely effective up to 1 microM. 4. The contractile response to bradykinin was: (a) unaffected by either tetrodotoxin (1 microM), in vitro capsaicin desensitization (10 microM for 30 min) or apamin (0.1 microM); (b) antagonized by indomethacin (5 microM), the prostaglandin receptor antagonist SC-19220 (100 microM) or the B2 receptor antagonist [D-Arg0, Hyp3, Thi5,8, Phe7]-bradykinin (10 micron) and (c) almost abolished by nifedipine (1 microM). 5. The antagonism of the contractile response to bradykinin produced by indomethacin and SC-19220 was non-additive while that produced by indomethacin and the B2 receptor antagonist was additive. 6. The relaxant response to bradykinin was unaffected by tetrodotoxin, in vitro capsaicin desensitization or indomethacin but antagonized in a competitive manner by the B2 receptor antagonist. Further, this response was abolished by apamin (0.1 microM) but unaffected by glibenclamide (1 microM). 7. Bradykinin (10 microM) produced a consistent release of calcitonin gene-related peptide-like immunoreactivity (CGRP-LI) but not substance P-LI from the guinea-pig bladder muscle. CGRP-LI release by bradykinin was greatly reduced in bladders exposed to indomethacin. [des-Arg9]-bradykinin (10 microM) was ineffective. 8. We conclude that: (a) bradykinin-induced contraction involves activation of both

  19. Induction of B(1)-kinin receptors in vascular smooth muscle cells: cellular mechanisms of map kinase activation.

    PubMed

    Christopher, J; Velarde, V; Jaffa, A A

    2001-09-01

    Vascular smooth muscle cell (VSMC) proliferation is a prominent feature of the atherosclerotic process that occurs after endothelial injury. Although a vascular wall kallikrein-kinin system has been described, its contribution to vascular disease remains undefined. Because the B(1)-kinin receptor subtype (B1KR) is induced in VSMCs only in response to injury, we hypothesize that this receptor may be mediating critical events in the progression of vascular disease. In the present study, we provide evidence that des-Arg(9)-bradykinin (dABK) (10(-8) M), acting through B1KR, stimulates the phosphorylation of mitogen-activated protein kinase (MAPK) (p42(mapk) and p44(mapk)). Activation of MAPK by dABK is mediated via a cholera toxin-sensitive pathway and appears to involve protein kinase C, Src kinase, and MAPK kinase. These findings demonstrate that the activation of B1KR in VSMCs leads to the generation of second messengers that converge to activate MAPK and provide a rationale to investigate the mitogenic actions of dABK in vascular injury.

  20. Enhanced Ca(2+) response and stimulation of prostaglandin release by the bradykinin B2 receptor in human retinal pigment epithelial cells primed with proinflammatory cytokines.

    PubMed

    Catalioto, Rose-Marie; Valenti, Claudio; Maggi, Carlo Alberto; Giuliani, Sandro

    2015-09-15

    Kallikrein, kininogen and kinin receptors are present in human ocular tissues including the retinal pigment epithelium (RPE), suggesting a possible role of bradykinin (BK) in physiological and/or pathological conditions. To test this hypothesis, kinin receptors expression and function was investigated for the first time in human fetal RPE cells, a model close to native RPE, in both control conditions and after treatment with proinflammatory cytokines. Results showed that BK evoked intracellular Ca(2+) transients in human RPE cells by activating the kinin B2 receptor. Pretreatment of the cells with TNF-α and/or IL-1β enhanced Ca(2+) response in a time- and concentration-dependent additive manner, whereas the potency of BK and that of the selective B2 receptor antagonist, fasitibant chloride, both in the nanomolar range, remained unaffected. Cytokines have no significant effect on cell number and viability and on the activity of other GPCRs such as the kinin B1, acetylcholine, ATP and thrombin receptors. Immunoblot analysis and immunofluorescence studies revealed that cytokines treatment was associated with an increase in both kinin B2 receptor and COX-2 expression and with the secretion of prostaglandin E1 and E2 into the extracellular medium. BK, through activation of the kinin B2 receptor, potentiated the COX-2 mediated prostaglandin release in cytokines-primed RPE cells while new protein synthesis and prostaglandin production contribute to the potentiating effect of cytokines on BK-induced Ca(2+) response. In conclusion, overall data revealed a cross-talk between the kinin B2 receptor and cytokines in human RPE in promoting inflammation, a key feature in retinal pathologies including diabetic retinopathy and macular edema.

  1. Senescence-associated phenotypes in Akita diabetic mice are enhanced by absence of bradykinin B2 receptors

    PubMed Central

    Kakoki, Masao; Kizer, Catherine M.; Yi, Xianwen; Takahashi, Nobuyuki; Kim, Hyung-Suk; Bagnell, C. Robert; Edgell, Cora-Jean S.; Maeda, Nobuyo; Jennette, J. Charles; Smithies, Oliver

    2006-01-01

    We have previously reported that genetically increased angiotensin-converting enzyme levels, or absence of the bradykinin B2 receptor, increase kidney damage in diabetic mice. We demonstrate here that this is part of a more general phenomenon — diabetes and, to a lesser degree, absence of the B2 receptor, independently but also largely additively when combined, enhance senescence-associated phenotypes in multiple tissues. Thus, at 12 months of age, indicators of senescence (alopecia, skin atrophy, kyphosis, osteoporosis, testicular atrophy, lipofuscin accumulation in renal proximal tubule and testicular Leydig cells, and apoptosis in the testis and intestine) are virtually absent in WT mice, detectable in B2 receptor–null mice, clearly apparent in mice diabetic because of a dominant mutation (Akita) in the Ins2 gene, and most obvious in Akita diabetic plus B2 receptor–null mice. Renal expression of several genes that encode proteins associated with senescence and/or apoptosis (TGF-β1, connective tissue growth factor, p53, α-synuclein, and forkhead box O1) increases in the same progression. Concomitant increases occur in 8-hydroxy-2′-deoxyguanosine, point mutations and deletions in kidney mitochondrial DNA, and thiobarbituric acid–reactive substances in plasma, together with decreases in the reduced form of glutathione in erythrocytes. Thus, absence of the bradykinin B2 receptor increases the oxidative stress, mitochondrial DNA damage, and many senescence-associated phenotypes already present in untreated Akita diabetic mice. PMID:16604193

  2. Bradykinin Enhances AMPA and NMDA Receptor Activity in Spinal Cord Dorsal Horn Neurons by Activating Multiple Kinases to Produce Pain Hypersensitivity

    PubMed Central

    Kohno, Tatsuro; Wang, Haibin; Amaya, Fumimasa; Brenner, Gary J.; Cheng, Jen-Kun; Ji, Ru-Rong; Woolf, Clifford J.

    2009-01-01

    Bradykinin potentiates synaptic glutamate release and action in the spinal cord via presynaptic and postsynaptic B2 receptors, contributing thereby to activity-dependent central sensitization and pain hypersensitivity (Wang et al., 2005). We have now examined the signaling pathways that are responsible for the postsynaptic modulatory actions of bradykinin on glutamatergic action and transmission in superficial dorsal horn neurons. B2 receptors are coexpressed in dorsal horn neurons with protein kinase A (PKA) and the δ isoform of protein kinase C (PKC), and we find that the augmentation by bradykinin of AMPA and NMDA receptor-mediated currents in lamina II neurons requires coactivation of both PKC and PKA. The activation of PKA is downstream of COX1 (cyclooxygenase-1). Extracellular signal-regulated kinase (ERK) activation is involved after the PKC and PKA coactivation, and intrathecal administration of bradykinin induces a thermal hyperalgesia in vivo, which is reduced by inhibition of ERK, PKA, and PKC. We conclude that bradykinin, by activating multiple kinases in dorsal horn neurons, potentiates glutamatergic synaptic transmission to produce pain hypersensitivity. PMID:18434532

  3. Lys-[Leu8,des-Arg9]-bradykinin blocks lipopolysaccharide-induced SHR aorta hyperpolarization by inhibition of Ca(++)- and ATP-dependent K+ channels.

    PubMed

    Farias, Nelson C; Feres, Teresa; Paiva, Antonio C M; Paiva, Therezinha B

    2004-09-13

    The mediators involved in the hyperpolarizing effects of lipopolysaccharide and of the bradykinin B1 receptor agonist des-Arg9-bradykinin on the rat aorta were investigated by comparing the responses of aortic rings of spontaneously hypertensive and normotensive Wistar rats. Endothelized rings from hypertensive rats were hyperpolarized by des-Arg9-bradykinin and lipopolysaccharide, whereas de-endothelized rings responded to lipopolysaccharide but not to des-Arg9-bradykinin. In endothelized preparations, the responses to des-Arg9-bradykinin were inhibited by Nomega-nitro-L-arginine and iberiotoxin. De-endothelized ring responses to lipopolysaccharide were inhibited by iberiotoxin, glibenclamide and B1 antagonist Lys-[Leu8,des-Arg9]-bradykinin. This antagonist also inhibited hyperpolarization by des-Arg9-bradykinin and by the á2-adrenoceptor agonist, brimonidine. Our results indicate that Ca(2+)-sensitive K+ channels are the final mediators of the responses to des-Arg9-bradykinin, whereas both Ca(2+)- and ATP-sensitive K+ channels mediate the responses to lipopolysaccharide. The inhibitory effects of Lys-[Leu8,des-Arg9]-bradykinin is due to a direct action on Ca(2+)- and ATP-sensitive potassium channels.

  4. Design and synthesis of potent bradykinin agonists containing a benzothiazepine moiety.

    PubMed

    Amblard, M; Daffix, I; Bedos, P; Bergé, G; Pruneau, D; Paquet, J L; Luccarini, J M; Bélichard, P; Dodey, P; Martinez, J

    1999-10-07

    A bradykinin analogue (H-Arg-Pro-Pro-Gly-Phe-Ser-D-BT-Arg-OH, 3) in which the Pro-Phe dipeptide was replaced by the (3S)[amino]-5-(carbonylmethyl)-2,3-dihydro-1, 5-benzothiazepin-4(5H)-one (D-BT) moiety has been synthesized. The same modification was performed on the potent bradykinin B(2) receptor antagonist HOE 140 (H-D-Arg-Arg-Pro-Hyp-Gly-Thi-Ser-D-Tic-Oic-Arg-OH), in which the -D-Tic-Oic- moiety was replaced by D-BT to yield H-D-Arg-Arg-Pro-Hyp-Gly-Thi-Ser-D-BT-Arg-OH, 1 (JMV1116). These compounds were examined in vitro for their binding affinity toward bradykinin B(1) and B(2) receptors as well as for their ability to interfere with bradykinin-induced contraction of both human umbilical vein and rat uterus. The two compounds 3 and 1 competed with [(3)H]bradykinin binding to the human cloned B(2) receptor giving K(i) values of 13 +/- 2 and 0.7 +/- 0.1 nM, respectively. Unexpectedly, both compounds were full bradykinin B(2) receptor agonists on the human umbilical vein (pD(2) = 6.60 +/- 0.07 for 3 and 6.80 +/- 0.08 for 1) and rat uterus (pD(2) = 7.20 +/- 0.09 for 3 and 7.50 +/- 0.09 for 1) preparations with the same efficacy as bradykinin. In addition 1 induced a concentration-dependent phosphoinositide production in CHO cells expressing the human cloned B(2) receptor. These data provide evidence for a bioactive conformation of bradykinin constrained at the dipeptide Pro-Phe.

  5. Downregulation of kinin B1 receptor function by B2 receptor heterodimerization and signaling.

    PubMed

    Zhang, Xianming; Brovkovych, Viktor; Zhang, Yongkang; Tan, Fulong; Skidgel, Randal A

    2015-01-01

    Signaling through the G protein-coupled kinin receptors B1 (kB1R) and B2 (kB2R) plays a critical role in inflammatory responses mediated by activation of the kallikrein-kinin system. The kB2R is constitutively expressed and rapidly desensitized in response to agonist whereas kB1R expression is upregulated by inflammatory stimuli and it is resistant to internalization and desensitization. Here we show that the kB1R heterodimerizes with kB2Rs in co-transfected HEK293 cells and natively expressing endothelial cells, resulting in significant internalization and desensitization of the kB1R response in cells pre-treated with kB2R agonist. However, pre-treatment of cells with kB1R agonist did not affect subsequent kB2R responses. Agonists of other G protein-coupled receptors (thrombin, lysophosphatidic acid) had no effect on a subsequent kB1R response. The loss of kB1R response after pretreatment with kB2R agonist was partially reversed with kB2R mutant Y129S, which blocks kB2R signaling without affecting endocytosis, or T342A, which signals like wild type but is not endocytosed. Co-endocytosis of the kB1R with kB2R was dependent on β-arrestin and clathrin-coated pits but not caveolae. The sorting pathway of kB1R and kB2R after endocytosis differed as recycling of kB1R to the cell surface was much slower than that of kB2R. In cytokine-treated human lung microvascular endothelial cells, pre-treatment with kB2R agonist inhibited kB1R-mediated increase in transendothelial electrical resistance (TER) caused by kB1R stimulation (to generate nitric oxide) and blocked the profound drop in TER caused by kB1R activation in the presence of pyrogallol (a superoxide generator). Thus, kB1R function can be downregulated by kB2R co-endocytosis and signaling, suggesting new approaches to control kB1R signaling in pathological conditions.

  6. Involvement of B2 receptor in bradykinin-induced proliferation and proinflammatory effects in human nasal mucosa-derived fibroblasts isolated from chronic rhinosinusitis patients.

    PubMed

    Tsai, Yih-Jeng; Hao, Sheng-Po; Chen, Chih-Li; Lin, Brian J; Wu, Wen-Bin

    2015-01-01

    Chronic rhinosinusitis (CRS) is a chronic inflammatory disease of the sinonasal mucosa either accompanied by polyp formation (CRSwNP) or without polyps (CRSsNP). CRSsNP accounts for the majority of CRS cases and is characterized by fibrosis and neutrophilic inflammation. However, the pathogenesis of CRS, especially CRSsNP, remains unclear. Immunohistochemistry of CRSsNP specimens in the present study showed that the submucosa, perivascular areas, and the mucous glands were abundant in fibroblasts. Therefore, we investigated the effects bradykinin (BK), an autacoid known to participate in inflammation, on human CRSsNP nasal mucosa-derived fibroblasts (NMDFs). BK increased CXCL1 and -8 secretion and mRNA expression with EC50 ranging from 0.15~0.35 μM. Moreover, BK enhanced cell proliferation and upregulated the expressions of proinflammatory molecules, including cell adhesion molecules (CAMs) and cyclooxygenase (COX)-1 and -2. These functionally caused an increase in monocyte adhesion to fibroblast monolayer. Using pharmacological intervention and BKR siRNA knockdown, we demonstrated that the BK-induced CXCL chemokine release, cell proliferation and COX and CAM expressions were mainly through the B2 receptor (B2R). Accordingly, the B2R was preferentially expressed in the NMDFs than B1R. The B2R was highly expressed in the CRSsNP than the control specimens, while the B1R and kininogen (KNG)/BK expression slightly increased in the CRSsNP mucosa. Collectively, we report here for the first time that fibroblasts, KNG/BK, and BKRs are overexpressed in CRSsNP mucosa and BK upregulates chemokine expression, proliferation, and proinflammatory molecule expression in NMDFs via B2R activation, which lead to a functional increase in monocyte-fibroblast interaction. Our findings reveal a critical role of fibroblast, KNG/BK, and BKRs in the development of CRSsNP.

  7. Metallopeptidase inhibition potentiates bradykinin-induced hyperalgesia

    PubMed Central

    Gomez, Ruben; Por, Elaine D.; Berg, Kelly A.; Clarke, William P.; Glucksman, Marc J.; Jeske, Nathaniel A.

    2011-01-01

    The neuropeptide bradykinin (BK) sensitizes nociceptor activation following its release in response to inflammatory injury. Thereafter, the bioactivity of bradykinin is controlled by the enzymatic activities of circulating peptidases. One such enzyme, the metalloendopeptidase EC3.4.24.15 (EP24.15), is co-expressed with bradykinin receptors in primary afferent neurons. In this study, utilizing approaches encompassing pharmacology, biochemistry, cell biology and behavioral animal models, we discover a crucial role for EP24.15 and the closely-related EP24.16 in modulating bradykinin-mediated hyperalgesia. Pharmacological analyses indicate that EP24.15 and EP24.16 inhibition significantly enhances bradykinin type-2 receptor activation by bradykinin in primary trigeminal ganglia cultures. In addition, bradykinin-induced sensitization of TRPV1 activation is increased in the presence of the EP24.15/16 inhibitor JA-2. Furthermore, behavioral analyses illustrate a significant dose-response relationship between JA-2 and bradykinin-mediated thermal hyperalgesia. These results indicate an important physiological role for the metallopeptidases EP24.15 and EP24.16 in regulating bradykinin-mediated sensitization of primary afferent nociceptors. PMID:21458920

  8. Trypanosoma cruzi invades host cells through the activation of endothelin and bradykinin receptors: a converging pathway leading to chagasic vasculopathy

    PubMed Central

    Andrade, Daniele; Serra, Rafaela; Svensjö, Erik; Lima, Ana Paula C; Ramos Junior, Erivan S; Fortes, Fabio S; Morandini, Ana Carolina F; Morandi, Verônica; Soeiro, Maria de N; Tanowitz, Herbert B; Scharfstein, Julio

    2012-01-01

    BACKGROUND AND PURPOSE Independent studies in experimental models of Trypanosoma cruzi appointed different roles for endothelin-1 (ET-1) and bradykinin (BK) in the immunopathogenesis of Chagas disease. Here, we addressed the hypothesis that pathogenic outcome is influenced by functional interplay between endothelin receptors (ETAR and ETBR) and bradykinin B2 receptors (B2R). EXPERIMENTAL APPROACH Intravital microscopy was used to determine whether ETR/B2R drives the accumulation of rhodamine-labelled leucocytes in the hamster cheek pouch (HCP). Inflammatory oedema was measured in the infected BALB/c paw of mice. Parasite invasion was assessed in CHO over-expressing ETRs, mouse cardiomyocytes, endothelium (human umbilical vein endothelial cells) or smooth muscle cells (HSMCs), in the presence/absence of antagonists of B2R (HOE-140), ETAR (BQ-123) and ETBR (BQ-788), specific IgG antibodies to each GPCRs; cholesterol or calcium-depleting drugs. RNA interference (ETAR or ETBR genes) in parasite infectivity was investigated in HSMCs. KEY RESULTS BQ-123, BQ-788 and HOE-140 reduced leucocyte accumulation in HCP topically exposed to trypomastigotes and blocked inflammatory oedema in infected mice. Acting synergistically, ETAR and ETBR antagonists reduced parasite invasion of HSMCs to the same extent as HOE-140. Exogenous ET-1 potentiated T. cruzi uptake by HSMCs via ETRs/B2R, whereas RNA interference of ETAR and ETBR genes conversely reduced parasite internalization. ETRs/B2R-driven infection in HSMCs was reduced in HSMC pretreated with methyl-β-cyclodextrin, a cholesterol-depleting drug, or in thapsigargin- or verapamil-treated target cells. CONCLUSIONS AND IMPLICATIONS Our findings suggest that plasma leakage, a neutrophil-driven inflammatory response evoked by trypomastigotes via the kinin/endothelin pathways, may offer a window of opportunity for enhanced parasite invasion of cardiovascular cells. LINKED ARTICLE This paper is commented on by D'Orléans-Juste et al

  9. Activation of kinin B1 receptor increases the release of metalloproteases-2 and -9 from both estrogen-sensitive and -insensitive breast cancer cells.

    PubMed

    Ehrenfeld, Pamela; Conejeros, Ivan; Pavicic, Maria F; Matus, Carola E; Gonzalez, Carlos B; Quest, Andrew F G; Bhoola, Kanti D; Poblete, Maria T; Burgos, Rafael A; Figueroa, Carlos D

    2011-02-01

    The kinin B(1) receptor (B(1)R) agonist Lys-des[Arg(9)]-bradykinin (LDBK) increases proliferation of estrogen-sensitive breast cancer cells by a process involving activation of the epidermal growth factor receptor (EGFR) and downstream signaling via the ERK1/2 mitogen-activated protein kinase pathway. Here, we investigated whether B(1)R stimulation induced release of the extracellular matrix metalloproteases MMP-2 and MMP-9 via ERK-dependent pathway in both estrogen-sensitive MCF-7 and -insensitive MDA-MB-231 breast cancer cells. Cells were stimulated with 1-100nM of the B(1)R agonist for variable time-points. Western blotting and gelatin zymography were used to evaluate the presence of MMP-2 and MMP-9 in the extracellular medium. Stimulation of B(1)R with as little as 1 nM LDBK induced the accumulation of these metalloproteases in the medium within 5-30min of stimulation. In parallel, immunocytochemistry revealed that metalloprotease levels in the breast cancer cells declined after stimulation. This effect was blocked either by pre-treating the cells with a B(1)R antagonist or by transfecting with B(1)R-specific siRNA. Activation of the ERK1/2 pathway and EGFR transactivation was required for release of metalloproteases because both the MEK1 inhibitor, PD98059, and AG1478, an inhibitor of the EGFR-tyrosine kinase activity, blocked this event. The importance of EGFR-dependent signaling was additionally confirmed since transfection of cells with the dominant negative EGFR mutant HERCD533 blocked the release of metalloproteases. Thus, activation of B(1)R is likely to enhance breast cancer cells invasiveness by releasing enzymes that degrade the extracellular matrix and thereby favor metastasis.

  10. Kinin B1 receptor regulates interactions between neutrophils and endothelial cells by modulating the levels of Mac-1, LFA-1 and intercellular adhesion molecule-1.

    PubMed

    Figueroa, Carlos D; Matus, Carola E; Pavicic, Francisca; Sarmiento, Jose; Hidalgo, Maria A; Burgos, Rafael A; Gonzalez, Carlos B; Bhoola, Kanti D; Ehrenfeld, Pamela

    2015-04-01

    Kinins are pro-inflammatory peptides that mimic the cardinal features of inflammation. We examined the concept that expression levels of endothelial intercellular adhesion molecule-1 (ICAM-1) and neutrophil integrins Mac-1 and LFA-1 are modulated by the kinin B1 receptor (B1R) agonist, Lys-des[Arg(9)]bradykinin (LDBK). Stimulation of endothelial cells with LDBK increased the levels of ICAM-1 mRNA transcripts/protein, and also of E-selectin and platelet endothelial adhesion molecule-1. ICAM-1 levels increased in a magnitude comparable with that produced by TNF-α. This stimulatory effect was reduced when endothelial cells, which had been previously transfected with a B1R small interfering RNA, were stimulated with LDBK, under comparable conditions. Similarly, LDBK produced a significant increase in protein levels of LFA-1 and Mac-1 integrins in human neutrophils, an effect that was reversed by pretreatment of cells with 10 µg/ml cycloheximide or a B1R antagonist. Functional experiments performed with post-confluent monolayers of endothelial cells stimulated with LDBK and neutrophils primed with TNF-α, and vice versa, resulted in enhanced adhesiveness between both cells. Neutralizing Abs to ICAM-1 and Mac-1 reduced the adhesion between them. Our results indicate that kinin B1R is a novel modulator that promotes adhesion of leukocytes to endothelial cells, critically enhancing the movement of neutrophils from the circulation to sites of inflammation.

  11. Complete blockade of the vasorelaxant effects of angiotensin-(1–7) and bradykinin in murine microvessels by antagonists of the receptor Mas

    PubMed Central

    Peiró, Concepción; Vallejo, Susana; Gembardt, Florian; Palacios, Erika; Novella, Susana; Azcutia, Verónica; Rodríguez-Mañas, Leocadio; Hermenegildo, Carlos; Sánchez-Ferrer, Carlos F; Walther, Thomas

    2013-01-01

    The heptapeptide angiotensin-(1–7) is a biologically active metabolite of angiotensin II, the predominant peptide of the renin–angiotensin system. Recently, we have shown that the receptor Mas is associated with angiotensin-(1–7)-induced signalling and mediates, at least in part, the vasodilatory properties of angiotensin-(1–7). However, it remained controversial whether an additional receptor could account for angiotensin-(1–7)-induced vasorelaxation. Here, we used two different angiotensin-(1–7) antagonists, A779 and d-Pro-angiotensin-(1–7), to address this question and also to study their influence on the vasodilatation induced by bradykinin. Isolated mesenteric microvessels from both wild-type and Mas-deficient C57Bl/6 mice were precontracted with noradrenaline, and vascular reactivity to angiotensin-(1–7) and bradykinin was subsequently studied using a small-vessel myograph. Furthermore, mechanisms for Mas effects were investigated in primary human umbilical vein endothelial cells. Both angiotensin-(1–7) and bradykinin triggered a concentration-dependent vasodilatation in wild-type microvessels, which was absent in the presence of a nitric oxide synthase inhibitor. In these vessels, the pre-incubation with the Mas antagonists A779 or d-Pro-angiotensin-(1–7) totally abolished the vasodilatory capacity of both angiotensin-(1–7) and bradykinin, which was nitric oxide mediated. Accordingly, Mas-deficient microvessels lacked the capacity to relax in response to either angiotensin-(1–7) or bradykinin. Pre-incubation of human umbilical vein endothelial cells with A779 prevented bradykinin-mediated NO generation and NO synthase phosphorylation at serine 1177. The angiotensin-(1–7) antagonists A779 and d-Pro-angiotensin-(1–7) equally block Mas, which completely controls the angiotensin-(1–7)-induced vasodilatation in mesenteric microvessels. Importantly, Mas also appears to be a critical player in NO-mediated vasodilatation induced by

  12. Hypoalgesia and altered inflammatory responses in mice lacking kinin B1 receptors.

    PubMed

    Pesquero, J B; Araujo, R C; Heppenstall, P A; Stucky, C L; Silva, J A; Walther, T; Oliveira, S M; Pesquero, J L; Paiva, A C; Calixto, J B; Lewin, G R; Bader, M

    2000-07-05

    Kinins are important mediators in cardiovascular homeostasis, inflammation, and nociception. Two kinin receptors have been described, B1 and B2. The B2 receptor is constitutively expressed, and its targeted disruption leads to salt-sensitive hypertension and altered nociception. The B1 receptor is a heptahelical receptor distinct from the B2 receptor in that it is highly inducible by inflammatory mediators such as bacterial lipopolysaccharide and interleukins. To clarify its physiological function, we have generated mice with a targeted deletion of the gene for the B1 receptor. B1 receptor-deficient animals are healthy, fertile, and normotensive. In these mice, bacterial lipopolysaccharide-induced hypotension is blunted, and there is a reduced accumulation of polymorphonuclear leukocytes in inflamed tissue. Moreover, under normal noninflamed conditions, they are analgesic in behavioral tests of chemical and thermal nociception. Using whole-cell patch-clamp recordings, we show that the B1 receptor was not necessary for regulating the noxious heat sensitivity of isolated nociceptors. However, by using an in vitro preparation, we could show that functional B1 receptors are present in the spinal cord, and their activation can facilitate a nociceptive reflex. Furthermore, in B1 receptor-deficient mice, we observed a reduction in the activity-dependent facilitation (wind-up) of a nociceptive spinal reflex. Thus, the kinin B1 receptor plays an essential physiological role in the initiation of inflammatory responses and the modulation of spinal cord plasticity that underlies the central component of pain. The B1 receptor therefore represents a useful pharmacological target especially for the treatment of inflammatory disorders and pain.

  13. MATE-1 modulation by kinin B1 receptor enhances cisplatin efflux from renal cells.

    PubMed

    Estrela, Gabriel R; Wasinski, Frederick; Felizardo, Raphael J F; Souza, Laura L; Câmara, Niels O S; Bader, Michael; Araujo, Ronaldo C

    2017-04-01

    Cisplatin is a drug widely used in chemotherapy that frequently causes severe renal dysfunction. Organic transporters have an important role to control the absorption and excretion of cisplatin in renal cells. Deletion and blockage of kinin B1 receptor has already been show to protect against cisplatin-induced acute kidney injury. To test whether it exerts its protective function by modulating the organic transporters in kidney, we studied kinin B1 receptor knockout mice and treatment with a receptor antagonist at basal state and in presence of cisplatin. Cisplatin administration caused downregulation of renal organic transporters; in B1 receptor knockout mice, this downregulation of organic transporters in kidney was absent; and treatment by a B1 receptor antagonist attenuated the downregulation of the transporter MATE-1. Moreover, kinin B1 receptor deletion and blockage at basal state resulted in higher renal expression of MATE-1. Moreover we observed that kinin B1 receptor deletion and blockage result in less accumulation of platinum in renal tissue. Thus, we propose that B1 receptor deletion and blockage protect the kidney from cisplatin-induced acute kidney injury by upregulating the expression of MATE-1, thereby increasing the efflux of cisplatin from renal cells.

  14. Null mutations at the p66 and bradykinin 2 receptor loci induce divergent phenotypes in the diabetic kidney

    PubMed Central

    Vashistha, Himanshu; Singhal, Pravin C.; Malhotra, Ashwani; Husain, Mohammad; Mathieson, Peter; Saleem, Moin A.; Kuriakose, Cyril; Seshan, Surya; Wilk, Anna; DelValle, Luis; Peruzzi, Francesca; Giorgio, Marco; Pelicci, Pier Giuseppe; Smithies, Oliver; Kim, Hyung-Suk; Kakoki, Masao; Reiss, Krzysztof

    2012-01-01

    Candidate genes have been identified that confer increased risk for diabetic glomerulosclerosis (DG). Mice heterozygous for the Akita (Ins2+/C96Y) diabetogenic mutation with a second mutation introduced at the bradykinin 2 receptor (B2R−/−) locus express a disease phenotype that approximates human DG. Src homology 2 domain transforming protein 1 (p66) controls mitochondrial metabolism and cellular responses to oxidative stress, aging, and apoptosis. We generated p66-null Akita mice to test whether inactivating mutations at the p66 locus will rescue kidneys of Akita mice from disease-causing mutations at the Ins2 and B2R loci. Here we show null mutations at the p66 and B2R loci interact with the Akita (Ins2+/C96Y) mutation, independently and in combination, inducing divergent phenotypes in the kidney. The B2R−/− mutation induces detrimental phenotypes, as judged by increased systemic and renal levels of oxidative stress, histology, and urine albumin excretion, whereas the p66-null mutation confers a powerful protection phenotype. To elucidate the mechanism(s) of the protection phenotype, we turned to our in vitro system. Experiments with cultured podocytes revealed previously unrecognized cross talk between p66 and the redox-sensitive transcription factor p53 that controls hyperglycemia-induced ROS metabolism, transcription of p53 target genes (angiotensinogen, angiotensin II type-1 receptor, and bax), angiotensin II generation, and apoptosis. RNA-interference targeting p66 inhibits all of the above. Finally, protein levels of p53 target genes were upregulated in kidneys of Akita mice but unchanged in p66-null Akita mice. Taken together, p66 is a potential molecular target for therapeutic intervention in DG. PMID:23019230

  15. Kinin-B2 Receptor Exerted Neuroprotection After Diisopropylfluorophosphate-induced Neuronal Damage

    PubMed Central

    Torres-Rivera, Wilmarie; Pérez, Dinely; Park, Keon-Young; Carrasco, Marimée; Platt, Manu O.; Eterović, Vesna A.; Ferchmin, Pedro A.; Ulrich, Henning; Martins, Antonio H.

    2013-01-01

    The kinin-B2 receptor (B2BKR) activated by its endogenous ligand bradykinin participates in various metabolic processes including control of arterial pressure and inflammation. Recently, functions for this receptor in brain development and protection against glutamate-provoked excitotoxicity have been proposed. Here, we report neuroprotective properties for bradykinin against organophosphate poisoning using acute hippocampal slices as an in vitro model. Following slice perfusion for 10 min with diisopropylfluorophosphate (DFP) to initiate the noxious stimulus, responses of pyramidal neurons upon an electric impulse were reduced to less than 30 % of control amplitudes. Effects on synaptic-elicited population spikes were reverted when preparations had been exposed to bradykinin 30 min after challenging with DFP. Accordingly, bradykinin-induced population spike recovery was abolished by HOE-140, a B2BKR antagonist. However, the kinin-B1 receptor (B1BKR) agonist Lys-des-Arg9-bradykinin, inducing phosphorylation of MEK/MAPK and cell death, abolished bradykinin-mediated neuroprotection, an effect, which was reverted by the ERK inhibitor PD98059. In agreement with pivotal B1BKR functions in this process, antagonism of endogenous B1BKR activity alone was enough for restoring population spike activity. On the other hand pralidoxime, an oxime, reactivating AChE after organophosphate poisoning, induced population spike recovery after DFP exposure in the presence of bradykinin and Lys-des-Arg9-bradykinin. Lys-des-Arg9-bradykinin did not revert protection exerted by pralidoxime, however when instead bradykinin and Ly-des-Arg9-bradykinin were superfused together, recovery of population spikes diminished. These findings again confirm the neuroprotective feature of bradykinin, which is, diminished by its endogenous metabolites, stimulating the B1BKR, providing a novel understanding of physiological roles of these receptors. PMID:23735753

  16. Bradykinin promotes migration and invasion of human immortalized trophoblasts

    PubMed Central

    2011-01-01

    Having demonstrated that the bradykinin B2 receptor (B2R) is expressed in cells that participate in trophoblast invasion in humans and guinea-pigs, we investigated the role of bradykinin (BK) on cell migration and invasion in the HTR-8/SVneo trophoblast cell line using wound healing and invasion assays. First, we documented that HTR-8/SVneo cells expressed kallikrein, B2R, B1R, MMP-2 and MMP-9 using immunocytochemistry. Incubation with BK (10.0 microMol/L) for 18 hours increased the migration index 3-fold in comparison to controls or to cells preincubated with the B2R antagonist HOE-140. BK (10.0 microMol/L) incubation yielded a similar number of proliferating and viable cells as controls, therefore the enhanced closure of the wound cannot be attributed to proliferating cells. Incubation with BK (10.0 microMol/L) for 18 hours increased the invasion index 2-fold in comparison to controls or to cells preincubated with the antagonist of the B2R. Neither the B1R ligand Lys-des-Arg9 BK, nor its antagonist Lys-(des-Arg9-Leu8), modified migration and invasion. Further support for the stimulatory effect of B2R activation on migration and invasion is provided by the 3-fold increase in the number of filopodia per cell versus controls or cells preincubated with the B2R antagonist. Bradykinin had no effect on the cellular protein content of the B2R, nor the MMP-9 and MMP-2 gelatinase activity in the culture media varied after incubation with BK. This study adds bradykinin-acting on the B2R-to the stimuli of trophoblast migration and invasion, an effect that should be integrated to other modifications of the kallikrein-kinin system in normal and pathological pregnancies. PMID:21729302

  17. Ca2+ signals mediated by bradykinin type 2 receptors in normal pancreatic stellate cells can be inhibited by specific Ca2+ channel blockade

    PubMed Central

    Gryshchenko, Oleksiy; Gerasimenko, Julia V.

    2015-01-01

    Key points Bradykinin may play a role in the autodigestive disease acute pancreatitis, but little is known about its pancreatic actions.In this study, we have investigated bradykinin‐elicited Ca2+ signal generation in normal mouse pancreatic lobules.We found complete separation of Ca2+ signalling between pancreatic acinar (PACs) and stellate cells (PSCs). Pathophysiologically relevant bradykinin concentrations consistently evoked Ca2+ signals, via B2 receptors, in PSCs but never in neighbouring PACs, whereas cholecystokinin, consistently evoking Ca2+ signals in PACs, never elicited Ca2+ signals in PSCs.The bradykinin‐elicited Ca2+ signals were due to initial Ca2+ release from inositol trisphosphate‐sensitive stores followed by Ca2+ entry through Ca2+ release‐activated channels (CRACs). The Ca2+ entry phase was effectively inhibited by a CRAC blocker.B2 receptor blockade reduced the extent of PAC necrosis evoked by pancreatitis‐promoting agents and we therefore conclude that bradykinin plays a role in acute pancreatitis via specific actions on PSCs. Abstract Normal pancreatic stellate cells (PSCs) are regarded as quiescent, only to become activated in chronic pancreatitis and pancreatic cancer. However, we now report that these cells in their normal microenvironment are far from quiescent, but are capable of generating substantial Ca2+ signals. We have compared Ca2+ signalling in PSCs and their better studied neighbouring acinar cells (PACs) and found complete separation of Ca2+ signalling in even closely neighbouring PACs and PSCs. Bradykinin (BK), at concentrations corresponding to the slightly elevated plasma BK levels that have been shown to occur in the auto‐digestive disease acute pancreatitis in vivo, consistently elicited substantial Ca2+ signals in PSCs, but never in neighbouring PACs, whereas the physiological PAC stimulant cholecystokinin failed to evoke Ca2+ signals in PSCs. The BK‐induced Ca2+ signals were mediated by B2 receptors and B2

  18. Primary Role for Kinin B1 and B2 Receptors in Glioma Proliferation.

    PubMed

    Nicoletti, Natália Fontana; Sénécal, Jacques; da Silva, Vinicius Duval; Roxo, Marcelo R; Ferreira, Nelson Pires; de Morais, Rafael Leite T; Pesquero, João Bosco; Campos, Maria Martha; Couture, Réjean; Morrone, Fernanda Bueno

    2016-11-16

    This study investigated the role of kinins and their receptors in malignant brain tumors. As a first approach, GL-261 glioma cells were injected (2 × 10(5) cells in 2 μl/2 min) into the right striatum of adult C57/BL6 wild-type, kinin B1 and B2 receptor knockout (KOB1R and KOB2R) and B1 and B2 receptor double knockout mice (KOB1B2R). The animals received the selective B1R (SSR240612) and/or B2R (HOE-140) antagonists by intracerebroventricular (i.c.v.) route at 5, 10, and 15 days. The tumor size quantification, mitotic index, western blot analysis, quantitative autoradiography, immunofluorescence, and confocal microscopy were carried out in brain tumor samples, 20 days after tumor induction. Our results revealed an uncontrolled tumor growing in KOB1R or SSR240612-treated mice, which was blunted by B2R blockade with HOE-140, suggesting a crosstalk between B1R and B2R in tumor growing. Combined treatment with B1R and B2R antagonists normalized the upregulation of tumor B1R and decreased the tumor size and the mitotic index, as was seen in double KOB1B2R. The B1R was detected on astrocytes in the tumor, indicating a close relationship between this receptor and astroglial cells. Noteworthy, an immunohistochemistry analysis of tumor samples from 16 patients with glioma diagnosis revealed a marked B1R immunopositivity in low-grade gliomas or in older glioblastoma individuals. Furthermore, the clinical data revealed a significantly higher immunopositivity for B1R, when compared to a lower B2R immunolabeling. Taken together, our results show that blocking simultaneously both kinin receptors or alternatively stimulating B1R may be of therapeutic value in the treatment of brain glioblastoma growth and malignancy.

  19. Activation of the Kinin B1 Receptor Attenuates Melanoma Tumor Growth and Metastasis

    PubMed Central

    Dillenburg-Pilla, Patricia; Maria, Andrea G.; Reis, Rosana I.; Floriano, Elaine Medeiros; Pereira, Cacilda Dias; De Lucca, Fernando Luiz; Ramos, Simone Gusmão; Pesquero, João B.; Jasiulionis, Miriam G.; Costa-Neto, Claudio M.

    2013-01-01

    Melanoma is a very aggressive tumor that does not respond well to standard therapeutic approaches, such as radio- and chemotherapies. Furthermore, acquiring the ability to metastasize in melanoma and many other tumor types is directly related to incurable disease. The B1 kinin receptor participates in a variety of cancer-related pathophysiological events, such as inflammation and angiogenesis. Therefore, we investigated whether this G protein-coupled receptor plays a role in tumor progression. We used a murine melanoma cell line that expresses the kinin B1 receptor and does not express the kinin B2 receptor to investigate the precise contribution of activation of the B1 receptor in tumor progression and correlated events using various in vitro and in vivo approaches. Activation of the kinin B1 receptor in the absence of B2 receptor inhibits cell migration in vitro and decreases tumor formation in vivo. Moreover, tumors formed from cells stimulated with B1-specific agonist showed several features of decreased aggressiveness, such as smaller size and infiltration of inflammatory cells within the tumor area, higher levels of pro-inflammatory cytokines implicated in the host anti-tumor immune response, lower number of cells undergoing mitosis, a poorer vascular network, no signs of invasion of surrounding tissues or metastasis and increased animal survival. Our findings reveal that activation of the kinin B1 receptor has a host protective role during murine melanoma tumor progression, suggesting that the B1 receptor could be a new anti-tumor GPCR and provide new opportunities for therapeutic targeting. PMID:23691222

  20. Activation of the kinin B1 receptor attenuates melanoma tumor growth and metastasis.

    PubMed

    Dillenburg-Pilla, Patricia; Maria, Andrea G; Reis, Rosana I; Floriano, Elaine Medeiros; Pereira, Cacilda Dias; De Lucca, Fernando Luiz; Ramos, Simone Gusmão; Pesquero, João B; Jasiulionis, Miriam G; Costa-Neto, Claudio M

    2013-01-01

    Melanoma is a very aggressive tumor that does not respond well to standard therapeutic approaches, such as radio- and chemotherapies. Furthermore, acquiring the ability to metastasize in melanoma and many other tumor types is directly related to incurable disease. The B1 kinin receptor participates in a variety of cancer-related pathophysiological events, such as inflammation and angiogenesis. Therefore, we investigated whether this G protein-coupled receptor plays a role in tumor progression. We used a murine melanoma cell line that expresses the kinin B1 receptor and does not express the kinin B2 receptor to investigate the precise contribution of activation of the B1 receptor in tumor progression and correlated events using various in vitro and in vivo approaches. Activation of the kinin B1 receptor in the absence of B2 receptor inhibits cell migration in vitro and decreases tumor formation in vivo. Moreover, tumors formed from cells stimulated with B1-specific agonist showed several features of decreased aggressiveness, such as smaller size and infiltration of inflammatory cells within the tumor area, higher levels of pro-inflammatory cytokines implicated in the host anti-tumor immune response, lower number of cells undergoing mitosis, a poorer vascular network, no signs of invasion of surrounding tissues or metastasis and increased animal survival. Our findings reveal that activation of the kinin B1 receptor has a host protective role during murine melanoma tumor progression, suggesting that the B1 receptor could be a new anti-tumor GPCR and provide new opportunities for therapeutic targeting.

  1. The Role of Scavenger Receptor B1 in Infection with Mycobacterium tuberculosis in a Murine Model

    PubMed Central

    Schäfer, Georgia; Guler, Reto; Murray, Graeme; Brombacher, Frank; Brown, Gordon D.

    2009-01-01

    Background The interaction between Mycobacterium tuberculosis (Mtb) and host cells is complex and far from being understood. The role of the different receptor(s) implicated in the recognition of Mtb in particular remains poorly defined, and those that have been found to have activity in vitro were subsequently shown to be redundant in vivo. Methods and Findings To identify novel receptors involved in the recognition of Mtb, we screened a macrophage cDNA library and identified scavenger receptor B class 1 (SR-B1) as a receptor for mycobacteria. SR-B1 has been well-described as a lipoprotein receptor which mediates both the selective uptake of cholesteryl esters and the efflux of cholesterol, and has also recently been implicated in the recognition of other pathogens. We show here that mycobacteria can bind directly to SR-B1 on transfected cells, and that this interaction could be inhibited in the presence of a specific antibody to SR-B1, serum or LDL. We define a variety of macrophage populations, including alveolar macrophages, that express this receptor, however, no differences in the recognition and response to mycobacteria were observed in macrophages isolated from SR-B1−/− or wild type mice in vitro. Moreover, when wild type and SR-B1−/− animals were infected with a low dose of Mtb (100 CFU/mouse) there were no alterations in survival, bacterial burdens, granuloma formation or cytokine production in the lung. However, significant reduction in the production of TNF, IFNγ, and IL10 were observed in SR-B1−/− mice following infection with a high dose of Mtb (1000 CFU/mouse), which marginally affected the size of inflammatory foci but did not influence bacterial burdens. Deficiency of SR-B1 also had no effect on resistance to disease under conditions of varying dietary cholesterol. We did observe, however, that the presence of high levels of cholesterol in the diet significantly enhanced the bacterial burdens in the lung, but this was independent of SR-B

  2. Kinin B(1) and B(2) receptors contribute to orofacial heat hyperalgesia induced by infraorbital nerve constriction injury in mice and rats.

    PubMed

    Luiz, Ana Paula; Schroeder, Samilla Driessen; Chichorro, Juliana Geremias; Calixto, João Batista; Zampronio, Aleksander Roberto; Rae, Giles Alexander

    2010-04-01

    Mechanisms coupled to kinin B(1) and B(2) receptors have been implicated in sensory changes associated to various models of neuropathy. The current study aimed to investigate if kinins also participate in orofacial thermal hyperalgesia induced by constriction of the infraorbital nerve (CION), a model of trigeminal neuropathic pain which displays persistent hypersensitivity to orofacial sensory stimulation, in rats and mice. Male Swiss mice (30-35g) or Wistar rats (200-250g; n=6-10 per group in both cases) underwent CION or sham surgery and were submitted repeatedly to application of heat ( approximately 50 degrees C) to the ipsilateral or contralateral snout, delivered by a heat source placed 1cm from the vibrissal pad. Decreases in latency to display head withdrawal or vigorous snout flicking were considered indicative of heat hyperalgesia. CION caused long-lasting heat hyperalgesia which started on Day 2 after surgery in both species and lasted up to Day 17 in mice and Day 10 in rats. Administration of DALBK or HOE-140 (peptidic B(1) and B(2) receptor antagonists, respectively; each at 3nmol in 10microl) onto the exposed infraorbital nerve of mice at the moment of surgery delayed the development of the thermal hyperalgesia. Systemic treatment on Day 5 (mice) or Day 4 (rats) with Des-Arg(9), Leu(8)-Bradykinin (DALBK, B(1) receptor antagonist, 0.1-1micromol/kg, i.p.) or HOE-140 (B(2) receptor antagonist, 0.001-1micromol/kg, i.p.) transiently reduced heat hyperalgesia in both species. Due to the peptidic nature of DALBK and HOE-140, it is likely that their effects reported herein resulted from blockade of peripheral kinin receptors. Thus, mechanisms operated by kinin B(1) and B(2) receptors, contribute to orofacial heat hyperalgesia induced by CION in both mice and rats. Perhaps kinin B(1) and B(2) receptor antagonists might constitute effective preventive and curative treatments for orofacial thermal hyperalgesia induced by nerve injury.

  3. Toxicity of aflatoxin B1 towards the vitamin D receptor (VDR).

    PubMed

    Costanzo, Paola; Santini, Antonello; Fattore, Luigi; Novellino, Ettore; Ritieni, Alberto

    2015-02-01

    This research describes an unexpected toxicity of the aflatoxin B1 towards the vitamin D receptors. Rickets is a childhood disease, and calcium deficiency is the aetiological cause in Africa, being primarily associated with nutritional problems; in this research the contribution of aflatoxin B1 exposure during the early months of life is an interesting factor to deepen in order to prevent liver damages or the development of rickets. The results show that the expression of vitamin D receptor in osteosarcoma cell line SAOS-2 is significantly down-modulated by exposure to aflatoxin B1. This seems to suggest that Aflatoxin B1, toxic towards the vitamin D receptor, interferes with the actions of the vitamin D on calcium binding gene expression in the kidney and intestine. Experimental data indicate a 58% and 86% decrease if the cells are exposed to 5 ng/mL and 50 ng/mL of aflatoxin B1, respectively. These results seem to indicate that natural occurrence of the aflatoxin B1 and allelic variant of vitamin D receptor on (F allele) increase the risk of developing rickets of African children.

  4. Ramipril-induced delayed myocardial protection against free radical injury involves bradykinin B2 receptor-NO pathway and protein synthesis

    PubMed Central

    Jin, Zhu-Qiu; Chen, Xiu

    1998-01-01

    The aim of the present study was to examine whether ramipril induces delayed myocardial protection against free radical injuries ex vivo and to determine the possible role of the bradykinin B2–nitric oxide (NO) pathway, prostaglandins(PGs) and protein synthesis in this delayed adaptive response.Rats were pretreated with ramipril (10 or 50 μg kg−1, i.v.) and hearts were isolated after 24, 48 and 72 h. Langendorff hearts were subjected to 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical-induced injury.Left ventricular developed pressure (LVDP) and its maximal increase velocity (+dP/dtmax), coronary flow (CF), heart rate (HR), lactate dehydrogenase (LDH) in coronary effluent and thiobarbituric acid reactive substances (TBARS) in the myocardium were measured.The results showed that in the DPPH control group, 20 min after free radical-induced injury, LVDP, +dP/dtmax, CF, HR declined, whereas TBARS and LDH increased significantly. The above cardiac function parameters were significantly improved in RAM-pretreated rats after 24 and 48 h.Pretreatment with HOE 140, the selective bradykinin B2 receptor antagonist, NG-nitro-L-arginine, the NO synthase inhibitor, and actinomycin D, the RNA transcription inhibitor, prior to ramipril injection abolished the beneficial effects of ramipril at 24 h while indomethacin, a cyclooxygenase inhibitor, pretreatment had no effect on ramipril-induced delayed protection.In conclusion, ramipril induces delayed myocardial protection against free radical injury in the rat heart. This delayed protection was sustained for 48 h, is associated with the bradykinin B2 receptor–NO pathway and depends on protein but not prostaglandin synthesis. PMID:9806340

  5. Inhibition of kinin B1 receptors attenuates pulmonary hypertension and vascular remodeling.

    PubMed

    Murugesan, Priya; Hildebrandt, Tobias; Bernlöhr, Christian; Lee, Dongwon; Khang, Gilson; Doods, Henri; Wu, Dongmei

    2015-10-01

    This study examined whether the kinin B1 receptor is involved in the pathogenesis of pulmonary hypertension, and whether its inhibition could reduce inflammation, pulmonary hypertension, vascular remodeling, and right heart dysfunction. Male Wistar rats underwent left pneumonectomy. Seven days later, the rats were injected subcutaneously with monocrotaline (60 mg/kg). The rats were then randomly assigned to receive treatment with vehicle or with BI113823 (a selective B1 receptor antagonist, 30 mg/kg, twice per day) via oral gavage from the day of monocrotaline injection to day 28. By day 28, BI113823-treated rats had significantly lower mean pulmonary artery pressure, less right ventricular hypertrophy, and pulmonary arterial neointimal formation than that of the vehicle-treated rats. Real-time polymerase chain reaction revealed that there was a significant increase in mRNA expression of B1 receptors in the lungs of monocrotaline-challenged pneumonectomized rats. Treatment with BI113823 significantly reduced macrophage recruitment, as measured via bronchoalveolar lavage. It also markedly reduced CD-68 positive macrophages and proliferating cell nuclear antigen positive cells in the perivascular areas, reduced expression of inducible nitric oxide synthase, matrix metalloproteinase 2 and 9, and B1 receptors compared with measurements in vehicle-treated rats. These findings demonstrate that kinin B1 receptors represent a novel therapeutic target for pulmonary arterial hypertension.

  6. Effects of bradykinin on venous capacitance in health and treated chronic heart failure

    PubMed Central

    Gunaruwan, Prasad; Maher, Abdul; Williams, Lynne; Sharman, James; Schmitt, Matthias; Campbell, Ross; Frenneaux, Michael

    2008-01-01

    In the present study, we investigated the effects of basal and intra-arterial infusion of bradykinin on unstressed forearm vascular volume (a measure of venous tone) and blood flow in healthy volunteers (n=20) and in chronic heart failure patients treated with ACEIs [ACE (angiotensin-converting enzyme) inhibitors] (n=16) and ARBs (angiotensin receptor blockers) (n=14). We used radionuclide plethysmography to examine the effects of bradykinin and of the bradykinin antagonists B9340 [B1 (type 1)/B2 (type 2) receptor antagonist] and HOE140 (B2 antagonist). Bradykinin infusion increased unstressed forearm vascular volume in a similar dose-dependent manner in healthy volunteers and ARB-treated CHF patients (healthy volunteers maximum 12.3±2.1%, P<0.001 compared with baseline; ARB-treated CHF patients maximum 9.3±3.3%, P<0.05 compared with baseline; P=not significant for difference between groups), but the increase in unstressed volume in ACEI-treated CHF patients was higher (maximum 28.8±7.8%, P<0.001 compared with baseline; P<0.05 for the difference between groups). In contrast, while the increase in blood flow in healthy volunteers (maximum 362±9%, P<0.001) and in ACEI-treated CHF patients (maximum 376±12%, P<0.001) was similar (P=not significant for the difference between groups), the increase in ARB-treated CHF patients was less (maximum 335±7%, P<0.001; P<0.05 for the difference between groups). Infusion of each receptor antagonist alone similarly reduced basal unstressed volume and blood flow in ACEI-treated CHF patients, but not in healthy volunteers or ARB-treated CHF patients. In conclusion, bradykinin does not contribute to basal venous tone in health, but in ACEI-treated chronic heart failure it does. In ARB-treated heart failure, venous responses to bradykinin are preserved but arterial responses are reduced compared with healthy controls. Bradykinin-mediated vascular responses in both health and heart failure are mediated by the B2, rather than the B1

  7. Soluble hyaluronan receptor RHAMM induces mitotic arrest by suppressing Cdc2 and cyclin B1 expression

    PubMed Central

    1996-01-01

    The hyaluronan (HA) receptor RHAMM is an important regulator of cell growth. Overexpression of RHAMM is transforming and is required for H- ras transformation. The molecular mechanism underlying growth control by RHAMM and other extracellular matrix receptors remains largely unknown. We report that soluble RHAMM induces G2/M arrest by suppressing the expression of Cdc2/Cyclin B1, a protein kinase complex essential for mitosis. Down-regulation of RHAMM by use of dominant negative mutants or antisense of mRNA also decreases Cdc2 protein levels. Suppression of Cdc2 occurs as a result of an increased rate of cdc2 mRNA degradation. Moreover, tumor cells treated with soluble RHAMM are unable to form lung metastases. Thus, we show that mitosis is directly linked to RHAMM through control of Cdc2 and Cyclin B1 expression. Failure to sustain levels of Cdc2 and Cyclin B1 proteins leads to cell cycle arrest. PMID:8666924

  8. Scavenger receptor B1 facilitates macrophage uptake of silver nanoparticles and cellular activation

    NASA Astrophysics Data System (ADS)

    Aldossari, Abdullah A.; Shannahan, Jonathan H.; Podila, Ramakrishna; Brown, Jared M.

    2015-07-01

    Due to increased use of silver nanoparticles (AgNPs) for their antimicrobial activity, concerns have risen regarding potential adverse human health effects. Scavenger receptor B1 (SR-B1), a major receptor for high-density lipoprotein (HDL), is expressed by macrophages and has also been reported to play a role in recognition of negatively charged particles. We, therefore, hypothesized that SR-B1 mediates macrophage uptake of AgNPs and inflammatory activation. To test this hypothesis, we exposed a mouse macrophage cell line RAW264.7 (RAW) and bone marrow-derived macrophages (BMDM) to 20 nm citrate-suspended AgNPs. To verify the role of the SR-B1 receptor, we utilized a SR-B1 inhibitor (Blt2). In vitro studies demonstrated uptake of AgNPs and HDL-coated AgNPs by macrophages which were significantly reduced following pretreatment with Blt2. Inflammatory cytokine arrays revealed that macrophages exposed to AgNPs up-regulated expression of Tnf- α, Oncostatin m (OSM), Ccl4, Il17f, Ccl7, and Ccl2, whereas Il16 was found to be down-regulated. Macrophage activation was observed following AgNP and HDL-coated AgNP exposure as measured by OSM protein production and increased surface expression of CD86. These markers of activation were reduced with Blt2 pretreatment. The in vitro findings were confirmed in vivo through pulmonary instillation of AgNPs in mice. Pulmonary instillation of AgNPs resulted in a recruitment of inflammatory cells that were reduced in SR-B1-deficient mice or following Blt2 pretreatment. This study suggests that SR-B1 plays a major role in cellular recognition of AgNPs and the induction of cell responses that could contribute to inflammation caused by AgNP exposure.

  9. Effects of CYP7B1-mediated catalysis on estrogen receptor activation.

    PubMed

    Pettersson, Hanna; Lundqvist, Johan; Norlin, Maria

    2010-09-01

    Most of the many biological effects of estrogens are mediated via the estrogen receptors ERalpha and beta. The current study examines the role of CYP7B1-mediated catalysis for activation of ER. Several reports suggest that CYP7B1 may be important for hormonal action but previously published studies are contradictory concerning the manner in which CYP7B1 affects ERbeta-mediated response. In the current study, we examined effects of several CYP7B1-related steroids on ER activation, using an estrogen response element (ERE) reporter system. Our studies showed significant stimulation of ER by 5-androstene-3beta,17beta-diol (Aene-diol) and 5alpha-androstane-3beta,17beta-diol (3beta-Adiol). In contrast, the CYP7B1-formed metabolites from these steroids did not activate the receptor, indicating that CYP7B1-mediated metabolism abolishes the ER-stimulating effect of these compounds. The mRNA level of HEM45, a gene known to be stimulated by estrogens, was strongly up-regulated by Aene-diol but not by its CYP7B1-formed metabolite, further supporting this concept. We did not observe stimulation by dehydroepiandrosterone (DHEA) or 7alpha-hydroxy-DHEA, previously suggested to affect ERbeta-mediated response. As part of these studies we examined metabolism of Aene-diol in pig liver which is high in CYP7B1 content. These experiments indicate that CYP7B1-mediated metabolism of Aene-diol is of a similar rate as the metabolism of the well-known CYP7B1 substrates DHEA and 3beta-Adiol. CYP7B1-mediated metabolism of 3beta-Adiol has been proposed to influence ERbeta-mediated growth suppression. Our results indicate that Aene-diol also might be important for ER-related pathways. Our data indicate that low concentrations of Aene-diol can trigger ER-mediated response equally well for both ERalpha and beta and that CYP7B1-mediated conversion of Aene-diol into a 7alpha-hydroxymetabolite will result in loss of action.

  10. The SH2B1 adaptor protein associates with a proximal region of the erythropoietin receptor.

    PubMed

    Javadi, Mojib; Hofstätter, Edda; Stickle, Natalie; Beattie, Bryan K; Jaster, Robert; Carter-Su, Christin; Barber, Dwayne L

    2012-07-27

    Gene targeting experiments have shown that the cytokine erythropoietin (EPO), its cognate erythropoietin receptor (EPO-R), and associated Janus tyrosine kinase, JAK2, are all essential for erythropoiesis. Structural-functional and murine knock-in experiments have suggested that EPO-R Tyr-343 is important in EPO-mediated mitogenesis. Although Stat5 binds to EPO-R phosphotyrosine 343, the initial Stat5-deficient mice did not have profound erythroid abnormalities suggesting that additional Src homology 2 (SH2) domain-containing effectors may bind to EPO-R Tyr-343 and couple to downstream signaling pathways. We have utilized cloning of ligand target (COLT) screening to demonstrate that EPO-R Tyr(P)-343 and Tyr(P)-401 bind to the SH2 domain-containing adaptor protein SH2B1β. Immunoprecipitation and in vitro mixing experiments reveal that EPO-R binds to SH2B1 in an SH2 domain-dependent manner and that the sequence that confers SH2B1 binding to the EPO-R is pYXXL. Previous studies have shown that SH2B1 binds directly to JAK2, but we show that in hematopoietic cells, SH2B1β preferentially associates with the EPO-R. SH2B1 is capable of constitutive association with EPO-R, which is necessary for its optimal SH2-dependent recruitment to EPO-R-Tyr(P)-343/Tyr(P)-401. We also demonstrate that SH2B1 is responsive to EPO stimulation and becomes phosphorylated, most likely on serines/threonines, in an EPO dose- and time-dependent manner. In the absence of SH2B1, we observe enhanced activation of signaling pathways downstream of the EPO-R, indicating that SH2B1 is a negative regulator of EPO signaling.

  11. Targeting the SR-B1 Receptor as a Gateway for Cancer Therapy and Imaging

    PubMed Central

    Mooberry, Linda K.; Sabnis, Nirupama A.; Panchoo, Marlyn; Nagarajan, Bhavani; Lacko, Andras G.

    2016-01-01

    Malignant tumors display remarkable heterogeneity to the extent that even at the same tissue site different types of cells with varying genetic background may be found. In contrast, a relatively consistent marker the scavenger receptor type B1 (SR-B1) has been found to be consistently overexpressed by most tumor cells. Scavenger Receptor Class B Type I (SR-BI) is a high density lipoprotein (HDL) receptor that facilitates the uptake of cholesterol esters from circulating lipoproteins. Additional findings suggest a critical role for SR-BI in cholesterol metabolism, signaling, motility, and proliferation of cancer cells and thus a potential major impact in carcinogenesis and metastasis. Recent findings indicate that the level of SR-BI expression correlate with aggressiveness and poor survival in breast and prostate cancer. Moreover, genomic data show that depending on the type of cancer, high or low SR-BI expression may promote poor survival. This review discusses the importance of SR-BI as a diagnostic as well as prognostic indicator of cancer to help elucidate the contributions of this protein to cancer development, progression, and survival. In addition, the SR-B1 receptor has been shown to serve as a potential gateway for the delivery of therapeutic agents when reconstituted high density lipoprotein nanoparticles are used for their transport to cancer cells and tumors. Opportunities for the development of new technologies, particularly in the areas of cancer therapy and tumor imaging are discussed. PMID:28018216

  12. Aflatoxin B1 invokes apoptosis via death receptor pathway in hepatocytes.

    PubMed

    Mughal, Muhammad Jameel; Xi, Peng; Yi, Zhou; Jing, Fang

    2017-01-31

    The fungal metabolites produced by Aspergillus flavus and Aspergillus parasiticus cause detrimental health effects on humans and animals. Particularly aflatoxin B1 (AFB1) is the most studied and a well-known global carcinogen, producing hepatotoxic, genotoxic and immunotoxic effects in multiple species. AFB1 is shown to provoke liver dysfunctioning by causing hepatocytes apoptosis and disturbing cellular enzymatic activities. In liver, AFB1 causes apoptosis via extrinsic mechanism because of high expression of death receptor pathway. The detailed mechanism of AFB1 induced hepatocytes apoptosis, via death receptor pathway still remains elusive. So the present study was conducted to explore apoptotic mechanism initiated by death receptors and associated genes in aflatoxin B1 induced liver apoptosis in chickens fed with AFB1 for 3 weeks. Results from the present study displayed histopathological and ultrastructural changes in liver such as hydropic degeneration, fatty vacuolar degeneration and proliferation of bile duct in hepatocytes in AFB1 group, along with imbalance between reactive oxygen species (ROS) and antioxidant defense system upon AFB1 ingestion. Moreover, AFB1 intoxicated chickens showed upregulation of death receptors FAS, TNFR1 and associated genes and downregulation of inhibitory apoptotic proteins XIAP and BCL-2. The results obtained from this novel and comprehensive study including histopathological, ultrastructural, flow cytometrical and death receptor pathway gene expression profiles, will facilitate better understanding of mechanisms and involvement of death receptor pathway in hepatocytes apoptosis induced by AFB1 and ultimately may be helpful in bringing down the toxigenic potential of AFB1.

  13. [Skin reactions to bradykinin].

    PubMed

    Rihoux, J P; Ramboer, I; Fadel, R

    1995-10-01

    A large series of experiments carried out in animals and humans suggest that histamine release is not involved in the leakage phenomenon induced by bradykinin (BK) challenge. These experiments comprise in vitro studies on skin and bronchial human mast cells and in vivo studies on guinea pig airways and human skin using mepyramine, chlorpheniramine and terfenadine as reference H1-anti-histamines. Nevertheless, it has been shown recently that the H1 antagonist cetirizine 10 mg p.o. markedly inhibits skin reactions induced by BK challenge (intradermal injection of 212 micrograms BK in 10 microL saline and prick test with a solution of 21.2 micrograms/microL). In a guinea pig model, this drug also inhibited the bronchospasm induced by increasing concentrations of BK given by iv route (0.25 to 2 micrograms/Kg) and aerosol (3 to 300 micrograms/Kg). This inhibition was similar to the one obtained with the specific BK antagonist HOE 140 (15 pM/Kg). New data in the literature suggest the existence of various pharmacological mediators possibly involved in the BK-induced reaction: neuromediators, nitric oxyde and PAF. They also suggest that this reaction presents itself as a well defined sequence of pharmacological events. Since we could show that there is no binding of cetirizine to a human recombinant B2 receptor in vitro, some hypotheses are raised in order to explain this unexpected inhibiting effect of cetirizine.

  14. B1-kinin receptors modulate Mesobuthus tamulus venom-induced vasosensory reflex responses in anesthetized rats

    PubMed Central

    Singh, Sanjeev K.; Deshpande, Shripad B.

    2016-01-01

    Objective: Intra-arterial injection of Mesobuthus tamulus (BT) venom produces reflex vasosensory responses modulating cardiorespiratory parameters in albino rats. The present study was conducted to understand the role of kinin receptors in modulating vasosensory reflexes evoked by BT venom. Materials and Methods: In urethane-anesthetized rats, tracheostomy was performed to keep the airway patent. The femoral artery was cannulated proximally, as well as distally, to record the blood pressure (BP) and to inject the chemicals, respectively. Electrocardiographic and respiratory excursions were recorded to compute the heart rate (HR) and respiratory rate (RR). A group of animals was pretreated with saline/kinin receptor antagonists intra-arterially (B1/B2 receptor antagonists) before the injection of venom. Results: After intra-arterial injection of BT venom (1 mg/kg), there was an immediate increase in RR, which reached to 40% within 30 s, followed by a decrease of 40%. Further, there was sustained increase in RR (50%) up to 60 min. The BP started to increase at 40 s, peaking at 5 min (50%), and remained above the initial level up to 60 min. The bradycardiac response started after 5 min which peaked (50% of initial) at 25 min and remained at that level up to 60 min. In B1 receptor antagonist (des-Arg) pretreated animals, venom-induced cardiovascular responses were attenuated (by 20–25% in mean arterial pressure and HR) significantly but not in B2 receptor antagonist (Hoe-140) pretreated animals. Either of the antagonists failed to alter the RR responses. Conclusions: BT venom-induced vasosensory reflex responses modulating cardiovascular parameters are mediated via B1-kinin receptors in anesthetized rats. PMID:27756949

  15. The mitochondrial and death receptor pathways involved in the thymocytes apoptosis induced by aflatoxin B1

    PubMed Central

    Chi, Xiaofeng; Li, Xiaochong; Jiang, Min; Fang, Jing; Cui, Hengmin; Lai, Weimin; Zhou, Yi; Zhou, Shan

    2016-01-01

    Aflatoxin B1 (AFB1) is a potent immunosuppressive agent in endotherms, which can be related to the up-regulated apoptosis of immune organs. In this study, we investigated the roles of the mitochondrial, death receptor, and endoplasmic reticulum pathways in Aflatoxin B1 induced thymocytes apoptosis. Chickens were fed an aflatoxin B1 containing diet (0.6 mg/kg AFB1) for 3 weeks. Our results showed that (1) AFB1 diet induced the decrease of T-cell subsets, morphological changes, and excessive apoptosis of thymus. (2) The excessive apoptosis involved the mitochondrial pathway (up-regulation of Bax, Bak, cytC and down-regulation of Bcl-2 and Bcl-xL) and death receptor pathway (up-regulation of FasL, Fas and FADD). (3) Oxidative stress, an apoptosis inducer, was confirmed in the thymus. In conclusion, this is the first study to demonstrate that mitochondrial and death receptor pathways involved in AFB1 induced thymocytes apoptosis in broilers. PMID:26933817

  16. A cleavable signal peptide enhances cell surface delivery and heterodimerization of Cerulean-tagged angiotensin II AT1 and bradykinin B2 receptor

    SciTech Connect

    Quitterer, Ursula; Pohl, Armin; Langer, Andreas; Koller, Samuel; AbdAlla, Said

    2011-06-10

    Highlights: {yields} A new FRET-based method detects AT1/B2 receptor heterodimerization. {yields} First time application of AT1-Cerulean as a FRET donor. {yields} Method relies on signal peptide-enhanced cell surface delivery of AT1-Cerulean. {yields} A high FRET efficiency revealed efficient heterodimerization of AT1/B2R proteins. {yields} AT1/B2R heterodimers were functionally coupled to desensitization mechanisms. -- Abstract: Heterodimerization of the angiotensin II AT1 receptor with the receptor for the vasodepressor bradykinin, B2R, is known to sensitize the AT1-stimulated response of hypertensive individuals in vivo. To analyze features of that prototypic receptor heterodimer in vitro, we established a new method that uses fluorescence resonance energy transfer (FRET) and applies for the first time AT1-Cerulean as a FRET donor. The Cerulean variant of the green fluorescent protein as donor fluorophore was fused to the C-terminus of AT1, and the enhanced yellow fluorescent protein (EYFP) as acceptor fluorophore was fused to B2R. In contrast to AT1-EGFP, the AT1-Cerulean fusion protein was retained intracellularly. To facilitate cell surface delivery of AT1-Cerulean, a cleavable signal sequence was fused to the receptor's amino terminus. The plasma membrane-localized AT1-Cerulean resembled the native AT1 receptor regarding ligand binding and receptor activation. A high FRET efficiency of 24.7% between membrane-localized AT1-Cerulean and B2R-EYFP was observed with intact, non-stimulated cells. Confocal FRET microscopy further revealed that the AT1/B2 receptor heterodimer was functionally coupled to receptor desensitization mechanisms because activation of the AT1-Cerulean/B2R-EYFP heterodimer with a single agonist triggered the co-internalization of AT1/B2R. Receptor co-internalization was sensitive to inhibition of G protein-coupled receptor kinases, GRKs, as evidenced by a GRK-specific peptide inhibitor. In agreement with efficient AT1/B2R heterodimerization

  17. Interruption of the ionic lock in the bradykinin B2 receptor results in constitutive internalization and turns several antagonists into strong agonists.

    PubMed

    Leschner, Jasmin; Wennerberg, Goeran; Feierler, Jens; Bermudez, Marcel; Welte, Benjamin; Kalatskaya, Irina; Wolber, Gerhard; Faussner, Alexander

    2013-01-01

    The DRY motif with the highly conserved R3.50 is a hallmark of family A G protein-coupled receptors (GPCRs). The crystal structure of rhodopsin revealed a salt bridge between R135(3.50) and another conserved residue, E247(6.30), in helix 6. This ionic lock was shown to maintain rhodopsin in its inactive state. Thus far, little information is available on how interruption of this ionic bond affects signaling properties of nonrhodopsin GPCRs, because the focus has been on mutations of R3.50, although this residue is indispensable for G protein activation. To investigate the importance of an ionic lock for overall receptor activity in a nonrhodopsin GPCR, we mutated R128(3.50) and E238(6.30) in the bradykinin (BK) B(2) receptor (B(2)R) and stably expressed the constructs in HEK293 cells. As expected, mutation of R3.50 resulted in lack of G protein activation. In addition, this mutation led to considerable constitutive receptor internalization. Mutation of E6.30 (mutants E6.30A and E6.30R) also caused strong constitutive internalization. Most intriguingly, however, although the two E6.30 mutants displayed no increased basal phosphatidylinositol hydrolysis, they gave a response to three different B(2)R antagonists that was almost comparable to that obtained with BK. In contrast, swapping of R3.50 and E6.30, thus allowing the formation of an inverse ionic bond, resulted in rescue of the wild type phenotype. These findings demonstrate for the first time, to our knowledge, that interruption of the ionic lock in a family A GPCR can have distinctly different effects on receptor internalization and G protein stimulation, shedding new light on its role in the activation process.

  18. The BRAIN TRIAL: a randomised, placebo controlled trial of a Bradykinin B2 receptor antagonist (Anatibant) in patients with traumatic brain injury

    PubMed Central

    2009-01-01

    Background Cerebral oedema is associated with significant neurological damage in patients with traumatic brain injury. Bradykinin is an inflammatory mediator that may contribute to cerebral oedema by increasing the permeability of the blood-brain barrier. We evaluated the safety and effectiveness of the non-peptide bradykinin B2 receptor antagonist Anatibant in the treatment of patients with traumatic brain injury. During the course of the trial, funding was withdrawn by the sponsor. Methods Adults with traumatic brain injury and a Glasgow Coma Scale score of 12 or less, who had a CT scan showing an intracranial abnormality consistent with trauma, and were within eight hours of their injury were randomly allocated to low, medium or high dose Anatibant or to placebo. Outcomes were Serious Adverse Events (SAE), mortality 15 days following injury and in-hospital morbidity assessed by the Glasgow Coma Scale (GCS), the Disability Rating Scale (DRS) and a modified version of the Oxford Handicap Scale (HIREOS). Results 228 patients out of a planned sample size of 400 patients were randomised. The risk of experiencing one or more SAEs was 26.4% (43/163) in the combined Anatibant treated group, compared to 19.3% (11/57) in the placebo group (relative risk = 1.37; 95% CI 0·76 to 2·46). All cause mortality in the Anatibant treated group was 19% and in the placebo group 15.8% (relative risk 1.20, 95% CI 0.61 to 2.36). The mean GCS at discharge was 12.48 in the Anatibant treated group and 13.0 in the placebo group. Mean DRS was 11.18 Anatibant versus 9.73 placebo, and mean HIREOS was 3.94 Anatibant versus 3.54 placebo. The differences between the mean levels for GCS, DRS and HIREOS in the Anatibant and placebo groups, when adjusted for baseline GCS, showed a non-significant trend for worse outcomes in all three measures. Conclusion This trial did not reach the planned sample size of 400 patients and consequently, the study power to detect an increase in the risk of serious

  19. Localization of relaxin receptors in arteries and veins, and region-specific increases in compliance and bradykinin-mediated relaxation after in vivo serelaxin treatment.

    PubMed

    Jelinic, Maria; Leo, Chen-Huei; Post Uiterweer, Emiel D; Sandow, Shaun L; Gooi, Jonathan H; Wlodek, Mary E; Conrad, Kirk P; Parkington, Helena; Tare, Marianne; Parry, Laura J

    2014-01-01

    Relaxin is a potent vasodilator of small resistance arteries and modifies arterial compliance in some systemic vascular beds, yet receptors for relaxin, such as RXFP1, have only been localized to vascular smooth muscle. This study first aimed to localize RXFP1 in rat arteries and veins from different organ beds and determine whether receptors are present in endothelial cells. We then tested the hypothesis that region-specific vascular effects of relaxin may be influenced by the cellular localization of RXFP1 within different blood vessels. The aorta, vena cava, mesenteric artery, and vein had significantly higher (P<0.05) RXFP1 immunostaining in endothelial cells compared with vascular smooth muscle, whereas the femoral artery and vein and small pulmonary arteries had higher (P<0.01) RXFP1 immunostaining in the vascular smooth muscle. Male rats were treated subcutaneously with recombinant human relaxin-2 (serelaxin; 4 μg/h) for 5 d; vasodilation and compliance in mesenteric and femoral arteries and veins were compared with placebo controls. Serelaxin significantly (P=0.04) reduced wall stiffness and increased volume compliance in mesenteric arteries but not in the other vessels examined. This was associated with changes in geometrical properties, and not compositional changes in the extracellular matrix. Serelaxin treatment had no effect on acetylcholine-mediated relaxation but significantly (P<0.001) enhanced bradykinin (BK)-mediated relaxation in mesenteric arteries, involving enhanced nitric oxide but not endothelium-derived hyperpolarization or vasodilatory prostanoids. In conclusion, there is differential distribution of RXFP1 on endothelial and smooth muscle across the vasculature. In rats, mesenteric arteries exhibit the greatest functional response to chronic serelaxin treatment.

  20. Ex Vivo Smooth Muscle Pharmacological Effects of a Novel Bradykinin-Related Peptide, and Its Analogue, from Chinese Large Odorous Frog, Odorrana livida Skin Secretions

    PubMed Central

    Xiang, Jie; Wang, Hui; Ma, Chengbang; Zhou, Mei; Wu, Yuxin; Wang, Lei; Guo, Shaodong; Chen, Tianbao; Shaw, Chris

    2016-01-01

    Bradykinin-related peptides (BRPs) are one of the most extensively studied frog secretions-derived peptide families identified from many amphibian species. The diverse primary structures of BRPs have been proven essential for providing valuable information in understanding basic mechanisms associated with drug modification. Here, we isolated, identified and characterized a dodeca-BRP (RAP-L1, T6-BK), with primary structure RAPLPPGFTPFR, from the skin secretions of Chinese large odorous frogs, Odorrana livida. This novel peptide exhibited a dose-dependent contractile property on rat bladder and rat ileum, and increased the contraction frequency on rat uterus ex vivo smooth muscle preparations; it also showed vasorelaxant activity on rat tail artery smooth muscle. In addition, the analogue RAP-L1, T6, L8-BK completely abolished these effects on selected rat smooth muscle tissues, whilst it showed inhibition effect on bradykinin-induced rat tail artery relaxation. By using canonical antagonist for bradykinin B1 or B2 type receptors, we found that RAP-L1, T6-BK -induced relaxation of the arterial smooth muscle was very likely to be modulated by B2 receptors. The analogue RAP-L1, T6, L8-BK further enhanced the bradykinin inhibitory activity only under the condition of co-administration with HOE140 on rat tail artery, suggesting a synergistic inhibition mechanism by which targeting B2 type receptors. PMID:27690099

  1. Species-specific pharmacology of maximakinin, an amphibian homologue of bradykinin: putative prodrug activity at the human B2 receptor and peptidase resistance in rats

    PubMed Central

    Jean, Melissa

    2017-01-01

    Maximakinin (MK), an amphibian peptide possessing the C-terminal sequence of bradykinin (BK), is a BK B2 receptor (B2R) agonist eliciting prolonged signaling. We reinvestigated this 19-mer for species-specific pharmacologic profile, in vivo confirmation of resistance to inactivation by angiotensin converting enzyme (ACE), value as a module for the design of fusion proteins that bind to the B2R in mammalian species and potential activity as a histamine releaser. Competition of the binding of [3H]BK to recombinant human myc-B2Rs in cells that express these receptors revealed that MK possessed a tenuous fraction (<0.1%) of the affinity of BK, despite being only ∼20-fold less potent than BK in a contractility assay based on the human isolated umbilical vein. These findings are reconciled by the generation of C-terminal fragments, like Lys-Gly-Pro-BK and Gly-Pro-BK, when the latent MK is incubated with human venous tissue (LC-MS), supporting activation via hydrolysis upstream of the BK sequence. At the rat recombinant myc-B2R, MK had a lesser affinity than that of BK, but with a narrower margin (6.2-fold, radioligand binding competition). Accordingly, MK (10 nM) stimulated calcium transients in cells that expressed the rat receptors, but not the human B2R. Recombinant MRGPRX2, a receptor that mediates cationic peptide-induced mast cell secretion, minimally responded by increased [Ca+2]i to MK at 10 µM. Enhanced green fluorescent protein fused to MK (EGFP-MK) labeled cells that expressed rat, but not human B2Rs. Intravenous MK induced dose-dependent hypotensive, vasodilator and tachycardic responses in anesthetized rats and the effects were antagonized by pretreatment with icatibant but not modified by pyrilamine or enalaprilat. Strong species-specific responses to the toxin-derived peptide MK and its prodrug status in the isolated human vein were evidenced. Accordingly, MK in the EGFP-MK fusion protein is a pharmacophore module that confers affinity for the rat B2R

  2. Role of Mas Receptor Antagonist A799 in Renal Blood Flow Response to Ang 1-7 after Bradykinin Administration in Ovariectomized Estradiol-Treated Rats.

    PubMed

    Dehghani, Aghdas; Saberi, Shadan; Nematbakhsh, Mehdi

    2015-01-01

    Background. The accompanied role of Mas receptor (MasR), bradykinin (BK), and female sex hormone on renal blood flow (RBF) response to angiotensin 1-7 is not well defined. We investigated the role of MasR antagonist (A779) and BK on RBF response to Ang 1-7 infusion in ovariectomized estradiol-treated rats. Methods. Ovariectomized Wistar rats received estradiol (OVE) or vehicle (OV) for two weeks. Catheterized animals were subjected to BK and A799 infusion and mean arterial pressure (MAP), RBF, and renal vascular resistance (RVR) responses to Ang 1-7 (0, 100, and 300 ng kg(-1) min(-1)) were determined. Results. Percentage change of RBF (%RBF) in response to Ang1-7 infusion increased in a dose-dependent manner. In the presence of BK, when MasR was not blocked, %RBF response to Ang 1-7 in OVE group was greater than OV group significantly (P < 0.05). Infusion of 300 ng kg(-1) min(-1) Ang 1-7 increased RBF by 6.9 ± 1.9% in OVE group versus 0.9 ± 1.8% in OV group. However when MasR was blocked, %RBF response to Ang 1-7 in OV group was greater than OVE group insignificantly. Conclusion. Coadministration of BK and A779 compared to BK alone increased RBF response to Ang 1-7 in vehicle treated rats. Such observation was not seen in estradiol treated rats.

  3. Role of Mas Receptor Antagonist A799 in Renal Blood Flow Response to Ang 1-7 after Bradykinin Administration in Ovariectomized Estradiol-Treated Rats

    PubMed Central

    Dehghani, Aghdas; Saberi, Shadan; Nematbakhsh, Mehdi

    2015-01-01

    Background. The accompanied role of Mas receptor (MasR), bradykinin (BK), and female sex hormone on renal blood flow (RBF) response to angiotensin 1-7 is not well defined. We investigated the role of MasR antagonist (A779) and BK on RBF response to Ang 1-7 infusion in ovariectomized estradiol-treated rats. Methods. Ovariectomized Wistar rats received estradiol (OVE) or vehicle (OV) for two weeks. Catheterized animals were subjected to BK and A799 infusion and mean arterial pressure (MAP), RBF, and renal vascular resistance (RVR) responses to Ang 1-7 (0, 100, and 300 ng kg−1 min−1) were determined. Results. Percentage change of RBF (%RBF) in response to Ang1-7 infusion increased in a dose-dependent manner. In the presence of BK, when MasR was not blocked, %RBF response to Ang 1-7 in OVE group was greater than OV group significantly (P < 0.05). Infusion of 300 ng kg−1 min−1 Ang 1-7 increased RBF by 6.9 ± 1.9% in OVE group versus 0.9 ± 1.8% in OV group. However when MasR was blocked, %RBF response to Ang 1-7 in OV group was greater than OVE group insignificantly. Conclusion. Coadministration of BK and A779 compared to BK alone increased RBF response to Ang 1-7 in vehicle treated rats. Such observation was not seen in estradiol treated rats. PMID:26421009

  4. Angiotensin-(1-7)-dependent vasorelaxation of the renal artery exhibits unique angiotensin and bradykinin receptor selectivity.

    PubMed

    Yousif, Mariam H M; Benter, Ibrahim F; Diz, Debra I; Chappell, Mark C

    2017-02-10

    Angiotensin-(1-7) [Ang-(1-7)] exhibits blood pressure lowering actions, inhibits cell growth, and reduces tissue inflammation and fibrosis which may functionally antagonize an activated Ang II-AT1 receptor axis. Since the vascular actions of Ang-(1-7) and the associated receptor/signaling pathways vary in different vascular beds, the current study established the vasorelaxant properties of the heptapeptide in the renal artery of male Wistar male rats. Ang-(1-7) produced an endothelium-dependent vasodilator relaxation of isolated renal artery segments pre-contracted by a sub-maximal concentration of phenylephrine (PE) (3×10(-7)M). Ang-(1-7) induced vasodilation of the rat renal artery with an ED50 of 3±1nM and a maximal response of 42±5% (N=10). The two antagonists (10(-5)M each) for the AT7/Mas receptor (MasR) [D-Pro(7)]-Ang-(1-7) and [D-Ala(7)]-Ang-(1-7) significantly reduced the maximal response to 12±1% and 18±3%, respectively. Surprisingly, the AT2R receptor antagonist PD123319, the AT1R antagonist losartan and B2R antagonist HOE140 (10(-6)M each) also significantly reduced Ang-(1-7)-induced relaxation to 12±2%, 22±3% and 14±7%, respectively. Removal of the endothelium or addition of the soluble guanylate cyclase (sGC) inhibitor ODQ (10(-5)M) essentially abolished the vasorelaxant response to Ang-(1-7) (10±4% and 10±2%, P <0.05). Finally, the NOS inhibitor LNAME (10(-4)M) reduced the response to 13±2% (p<0.05), but the cyclooxygenase inhibitor indomethacin failed to block the Ang-(1-7) response. We conclude that Ang-(1-7) exhibits potent vasorelaxant actions in the isolated renal artery that are dependent on an intact endothelium and the apparent stimulation of a NO-sGC pathway. Moreover, Ang-(1-7)-dependent vasorelaxation was sensitive to antagonists against the AT7/Mas, AT1, AT2 and B2 receptor subtypes.

  5. Kinin B1 and B2 receptors are overexpressed in the hippocampus of humans with temporal lobe epilepsy.

    PubMed

    Perosa, Sandra Regina; Argañaraz, Gustavo Adolfo; Goto, Eduardo Massatoshi; Costa, Luciana Gilbert Pessoa; Konno, Ana Carla; Varella, Pedro Paulo Vasconcellos; Santiago, Joselita Ferreira Carvalho; Pesquero, João Bosco; Canzian, Mauro; Amado, Debora; Yacubian, Elza Marcia; Carrete, Henrique; Centeno, Ricardo Silva; Cavalheiro, Esper Abrão; Silva, Jose Antonio; Mazzacoratti, Maria da Graça Naffah

    2007-01-01

    Molecular biology tools have been employed to investigate the participation of peptides in human temporal lobe epilepsy (TLE). Active polypeptides and their receptors have been related to several brain processes, such as inflammation, apoptosis, brain development, K(+) and Ca(2+) channels' activation, cellular growth, and induction of neuronal differentiation. Previous works have shown a neuroprotector effect for kinin B2 receptor and a deleterious, pro-epileptogenic action for kinin B1 receptor in animal models of TLE. The present work was delineated to analyze the kinin B1 and B2 receptors expression in the hippocampus of patients presenting refractory mesial TLE. The hippocampi were removed during the patients surgery in a procedure used for seizure control and compared with tissues obtained after autopsy. Nissl staining was performed to study the tissue morphology and immunohistochemistry, and Western blot was used to compare the distribution and levels of both receptors in the hippocampus. In addition, real time PCR was employed to analyze the gene expression of these receptors. Nissl staining showed sclerotic hippocampi with hilar, granular, and pyramidal cell loss in TLE patients. Immunohistochemistry and Western blot analyses showed increased expression of kinin B1 and B2 receptors but the real-time PCR data demonstrated increased mRNA level only for kinin B2 receptors, when compared with controls. These data show for the first time a relationship between human TLE and the kallikrein-kinin system, confirming ours previous results, obtained from experimental models of epilepsy.

  6. The CYP1B1_1358_GG genotype is associated with estrogen receptor-negative breast cancer.

    PubMed

    Justenhoven, Christina; Pierl, Christiane B; Haas, Susanne; Fischer, Hans-Peter; Baisch, Christian; Hamann, Ute; Harth, Volker; Pesch, Beate; Brüning, Thomas; Vollmert, Caren; Illig, Thomas; Dippon, Jürgen; Ko, Yon-Dschun; Brauch, Hiltrud

    2008-09-01

    Cytochrome P450 1B1 (CYP1B1) is a major enzyme in the initial catabolic step of estradiol (E2) metabolism and belongs to the multitude of genes regulated by the estrogen receptor alpha (ERalpha). The common non-synonymous polymorphisms CYP1B1_1358_A>G and CYP1B1_1294_C>G increase CYP1B1 enzymatic activity. Given a relationship between CYP1B1 and breast tumor E2 level as well as E2 level and breast tumor ERalpha expression it is of interest to know whether CYP1B1 polymorphisms have an impact on the ERalpha status of breast cancer. We genotyped the GENICA population-based breast cancer case-control collection (1,021 cases, 1,015 controls) by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and investigated in cases the association between genotypes and tumor ERalpha status (739 ERalpha positive cases; 212 ERalpha negative cases) by logistic regression. We observed a significant association between the homozygous variant CYP1B1_1358_GG genotype and negative ERalpha status (P = 0.005; OR 2.82, 95% CI: 1.37-5.82) with a highly significant Ptrend for CYP1B1_1358_A>G and negative ERalpha status (P = 0.003). We also observed an association of CYP1B1_1358_GG and negative PR status (P = 0.015; OR 2.36, 95% CI: 1.18-4.70) and a Ptrend of 0.111 for CYP1B1_1358_A>G and negative progesterone receptor (PR) status. We conclude that the CYP1B1_1358_A>G polymorphism has an impact on ERalpha status in breast cancer in that the CYP1B1_1358_GG genotype known to encode higher CYP1B1 activity is associated with ERalpha negativity.

  7. The semaphorin receptor plexin-B1 specifically interacts with active Rac in a ligand-dependent manner

    PubMed Central

    Vikis, Haris G.; Li, Weiquan; He, Zhigang; Guan, Kun-Liang

    2000-01-01

    Semaphorin molecules serve as axon guidance signals that regulate the navigation of neuronal growth cones. Semaphorins have also been implicated in other biological processes, including the immune response. Plexins, acting either alone or in complex with neuropilins, have recently been identified as functional semaphorin receptors. However, the mechanisms of signal transduction by plexins remain largely unknown. We have demonstrated a direct interaction between plexin-B1 and activated Rac. Rac specifically interacts with the cytosolic domain of plexin-B1, but not with that of plexin-A3 or -C1. Neither RhoA nor Cdc42 interacts with plexin-B1, indicating that the Rac/plexin-B1 interaction is highly specific. The binding of GTP and the integrity of the Rac effector domain are required for the interaction with plexin-B1. Furthermore, we have identified that a Cdc42/Rac interactive binding (CRIB) motif in the cytosolic domain of plexin-B1 is essential for its interaction with active Rac. We have also observed that the semaphorin CD100, a ligand for plexin-B1, stimulates the interaction between plexin-B1 and active Rac. Our results support a model by which activated Rac plays a role in mediating semaphorin signals, resulting in reorganization of actin cytoskeletal structure. PMID:11035813

  8. The mechanism of action of two bradykinin-potentiating peptides on isolated smooth muscle.

    PubMed

    Ufkes, J G; Aarsen, P N; van der Meer, C

    1977-07-15

    Bradykinin-induced contractions in the guinea-pig ileum were potentiated by the peptides A-VI-5 (Val-Glu-Ser-Ser-Lys) and BPP5a (Pyr-Lys-Trp-Ala-Pro), while the contractions induced by other agonists were not affected. Neither peptide added alone caused any response. Previous addition of the peptides shortened the latent period following the addition of bradykinin to a value corresponding to the contraction height with an equivalent dose of bradykinin added alone. Bradykinin in contact with a piece of ileum was inactivated at a relatively slow rate. This inactivation was not inhibited by either A-VI-5 or BPP5a in doses causing potentiation. Suppression of the cholinergic activity by cooling, atropine, morphine or tetrodotoxin did not influence the potentiating activity. Addition of the peptides at the moment a submaximal contraction due to bradykinin had been fully established, increased the contraction height within seconds. The two peptides caused a parallel shift to the left of the dose-effect curve of bradykinin, whereas the maximum bradykinin effect remained unchanged. It is concluded that sensitization of bradykinin receptors due to an increased affinity of the receptor for bradykinin is the hypothesis which best fits the experimental findings.

  9. Characterization of 5-HT receptors mediating constriction of porcine carotid arteriovenous anastomoses; involvement of 5-HT1B/1D and novel receptors

    PubMed Central

    De Vries, Peter; Villalón, Carlos M; Heiligers, Jan P C; Saxena, Pramod R

    1998-01-01

    It was previously shown that porcine cranial arteriovenous anastomoses (AVAs) constrict to 5-hydroxytryptamine (5-HT), ergotamine, dihydroergotamine, as well as sumatriptan and that sumatriptan acts exclusively via 5-HT1B/1D receptors. The present study was devoted to establish the contribution of 5-HT1B/1D receptors in the constriction of AVAs elicited by 5-HT (in presence of 0.5 mg kg−1 ketanserin), ergotamine and dihydroergotamine in anaesthetized pigs.Intracarotid infusion of 5-HT (2 μg kg−1 min−1) and intravenous doses of ergotamine (2.5–20 μg kg−1) and dihydroergotamine (3–100 μg kg−1) reduced AVA and increased nutrient blood flows and vascular conductances. The vasodilator response to 5-HT, observed mainly in the skin and ear, was much more prominent than that of the ergot alkaloids.Treatment with the 5-HT1B/1D receptor antagonist GR127935 (0.5 mg kg−1, i.v.) significantly attenuated both ergot-induced AVA constriction and arteriolar dilatation, whereas GR127935 only slightly affected the carotid vascular effects of 5-HT.The results suggest that 5-HT constricts carotid AVAs primarily via receptors, which seem to differ from those (5-HT1B/1D) stimulated by sumatriptan. The ergot alkaloids produce AVA constriction for a substantial part via 5-HT1B/1D receptors, but also stimulate unidentified receptors. Both these non-5-HT1B/1D receptors may be targets for the development of novel antimigraine drugs.The moderate vasodilator response to the ergot derivatives seems to be mediated, at least in part, by 5-HT1B/1D receptors, whereas the arteriolar dilatation caused by 5-HT may be mediated by other, possibly 5-HT7 receptors. PMID:9605562

  10. Differential regulation of inducible and endothelial nitric oxide synthase by kinin B1 and B2 receptors

    PubMed Central

    Kuhr, F.; Lowry, J.; Zhang, Y.; Brovkovych, V.; Skidgel, R.A.

    2010-01-01

    Kinins are vasoactive peptides that play important roles in cardiovascular homeostasis, pain and inflammation. After release from their precursor kininogens, kinins or their C-terminal des-Arg metabolites activate two distinct G protein-coupled receptors (GPCR), called B2 (B2R) or B1 (B1R). The B2R is expressed constitutively with a wide tissue distribution. In contrast, the B1R is not expressed under normal conditions but is upregulated by tissue insult or inflammatory mediators. The B2R is considered to mediate many of the acute effects of kinins while the B1R is more responsible for chronic responses in inflammation. Both receptors can couple to Gαi and Gαq families of G proteins to release mediators such as nitric oxide (NO), arachidonic acid, prostaglandins, leukotrienes and endothelium derived hyperpolarizing factor and can induce the release of other inflammatory agents. The focus of this review is on the different transduction events that take place upon B2R and B1R activation in human endothelial cells that leads to generation of NO via activation of different NOS isoforms. Importantly, B2R-mediated eNOS activation leads to a transient (~ 5 min) output of NO in control endothelial cells whereas in cytokine-treated endothelial cells, B1R activation leads to very high and prolonged (~90 min) NO production that is mediated by a novel signal transduction pathway leading to post-translational activation of iNOS. PMID:20045558

  11. Bradykinin Induces TRPV1 Exocytotic Recruitment in Peptidergic Nociceptors.

    PubMed

    Mathivanan, Sakthikumar; Devesa, Isabel; Changeux, Jean-Pierre; Ferrer-Montiel, Antonio

    2016-01-01

    Transient receptor potential vanilloid I (TRPV1) sensitization in peripheral nociceptors is a prominent phenomenon that occurs in inflammatory pain conditions. Pro-algesic agents can potentiate TRPV1 activity in nociceptors through both stimulation of its channel gating and mobilization of channels to the neuronal surface in a context dependent manner. A recent study reported that ATP-induced TRPV1 sensitization in peptidergic nociceptors involves the exocytotic release of channels trafficked by large dense core vesicles (LDCVs) that cargo alpha-calcitonin gene related peptide alpha (αCGRP). We hypothesized that, similar to ATP, bradykinin may also use different mechanisms to sensitize TRPV1 channels in peptidergic and non-peptidergic nociceptors. We found that bradykinin notably enhances the excitability of peptidergic nociceptors, and sensitizes TRPV1, primarily through the bradykinin receptor 2 pathway. Notably, bradykinin sensitization of TRPV1 in peptidergic nociceptors was significantly blocked by inhibiting Ca(2+)-dependent neuronal exocytosis. In addition, silencing αCGRP gene expression, but not substance P, drastically reduced bradykinin-induced TRPV1 sensitization in peptidergic nociceptors. Taken together, these findings indicate that bradykinin-induced sensitization of TRPV1 in peptidergic nociceptors is partially mediated by the exocytotic mobilization of new channels trafficked by αCGRP-loaded LDCVs to the neuronal membrane. Our findings further imply a central role of αCGRP peptidergic nociceptors in peripheral algesic sensitization, and substantiate that inhibition of LDCVs exocytosis is a valuable therapeutic strategy to treat pain, as it concurrently reduces the release of pro-inflammatory peptides and the membrane recruitment of thermoTRP channels.

  12. Bradykinin Induces TRPV1 Exocytotic Recruitment in Peptidergic Nociceptors

    PubMed Central

    Mathivanan, Sakthikumar; Devesa, Isabel; Changeux, Jean-Pierre; Ferrer-Montiel, Antonio

    2016-01-01

    Transient receptor potential vanilloid I (TRPV1) sensitization in peripheral nociceptors is a prominent phenomenon that occurs in inflammatory pain conditions. Pro-algesic agents can potentiate TRPV1 activity in nociceptors through both stimulation of its channel gating and mobilization of channels to the neuronal surface in a context dependent manner. A recent study reported that ATP-induced TRPV1 sensitization in peptidergic nociceptors involves the exocytotic release of channels trafficked by large dense core vesicles (LDCVs) that cargo alpha-calcitonin gene related peptide alpha (αCGRP). We hypothesized that, similar to ATP, bradykinin may also use different mechanisms to sensitize TRPV1 channels in peptidergic and non-peptidergic nociceptors. We found that bradykinin notably enhances the excitability of peptidergic nociceptors, and sensitizes TRPV1, primarily through the bradykinin receptor 2 pathway. Notably, bradykinin sensitization of TRPV1 in peptidergic nociceptors was significantly blocked by inhibiting Ca2+-dependent neuronal exocytosis. In addition, silencing αCGRP gene expression, but not substance P, drastically reduced bradykinin-induced TRPV1 sensitization in peptidergic nociceptors. Taken together, these findings indicate that bradykinin-induced sensitization of TRPV1 in peptidergic nociceptors is partially mediated by the exocytotic mobilization of new channels trafficked by αCGRP-loaded LDCVs to the neuronal membrane. Our findings further imply a central role of αCGRP peptidergic nociceptors in peripheral algesic sensitization, and substantiate that inhibition of LDCVs exocytosis is a valuable therapeutic strategy to treat pain, as it concurrently reduces the release of pro-inflammatory peptides and the membrane recruitment of thermoTRP channels. PMID:27445816

  13. Pharmacological characterisation of a cell line expressing GABA B1b and GABA B2 receptor subunits.

    PubMed

    Hirst, Warren D; Babbs, Adam J; Green, Andrew; Minton, Jayne A L; Shaw, Tracy E; Wise, Alan; Rice, Simon Q; Pangalos, Menelas N; Price, Gary W

    2003-04-01

    The gamma-aminobutyric acid (GABA(B)) receptor has been shown to be a heterodimer consisting of two receptor subunits, GABA(B1) and GABA(B2). We have stably co-expressed these two subunits in a CHO cell line, characterised its pharmacology and compared it to the native receptor in rat brain membranes. Radioligand binding using [3H]CGP54626A demonstrated a similar rank order of potency between recombinant and native receptors: CGP62349>CGP54626A>SCH 50911>3-aminopropylphosphinicacid(3-APPA)>GABA>baclofen>saclofen>phaclofen. However, differences were observed in the affinity of agonists, which were higher at the native receptor, suggesting that in the recombinant system a large number of the receptors were in the low agonist affinity state. In contrast, [35S]GTPgammaS binding studies did not show any differences between recombinant and native receptors with the full agonists GABA and 3-APPA. Measurement of cAMP accumulation in the cells revealed a degree of endogenous coupling of the receptors to G-proteins. This is most likely to be due to the high expression levels of receptors (B(max)=22.5+/-2.5pmol/mg protein) in this experimental system. There was no evidence of GABA(B2) receptors, when expressed alone, binding [3H]CGP54626A, [3H]GABA, [3H]3-APPA nor of GABA having any effect on basal [35S]GTPgammaS binding or cAMP levels.

  14. Cell entry of hepatitis C virus requires a set of co-receptors that include the CD81 tetraspanin and the SR-B1 scavenger receptor.

    PubMed

    Bartosch, Birke; Vitelli, Alessandra; Granier, Christelle; Goujon, Caroline; Dubuisson, Jean; Pascale, Simona; Scarselli, Elisa; Cortese, Riccardo; Nicosia, Alfredo; Cosset, François-Loïc

    2003-10-24

    Several cell surface molecules have been proposed as receptor candidates, mediating cell entry of hepatitis C virus (HCV) on the basis of their physical association with virions or with soluble HCV E2 glycoproteins. However, due to the lack of infectious HCV particles, evidence that these receptor candidates support infection was missing. Using our recently described infectious HCV pseudotype particles (HCVpp) that display functional E1E2 glycoprotein complexes, here we show that HCV is a pH-dependent virus, implying that its receptor component(s) mediate virion internalization by endocytosis. Expression of the CD81 tetraspanin in non-permissive CD81-negative hepato-carcinoma cells was sufficient to restore susceptibility to HCVpp infection, confirming its critical role as a cell attachment factor. As a cell surface molecule likely to mediate endosomal trafficking, we demonstrate that the human scavenger receptor class B type 1 (SR-B1), a high-density lipoprotein-internalization molecule that we previously proposed as a novel HCV receptor candidate due to its affinity with E2 glycoproteins, is required for infection of CD81-expressing hepatic cells. By receptor competition assays, we found that SR-B1 antibodies that blocked binding of soluble E2 could prevent HCVpp infectivity. Furthermore, we establish that the hyper-variable region 1 of the HCV E2 glycoprotein is a critical determinant mediating entry in SR-B1-positive cells. Finally, by correlating expression of HCV receptors and infectivity, we suggest that, besides CD81 and SR-B1, additional hepatocyte-specific co-factor(s) are necessary for HCV entry.

  15. Comparative study on the mechanism of bradykinin potentiation induced by bradykinin-potentiating peptide 9a, enalaprilat and kinin-potentiating peptide.

    PubMed

    Rodrigues, M S; Schaffel, R; Assreuy, J

    1992-06-17

    The action of a kinin-potentiating peptide (KPP) obtained from tryptic digestion of human serum proteins was compared with that of bradykinin-potentiating peptide 9a (BPP9a; obtained from snake venom) and enalaprilat (a synthetic inhibitor of angiotensin-converting enzyme; ACE) as a means of understanding the mechanism of action of KPP on smooth muscle. KPP potentiated bradykinin-induced contractile effects in guinea-pig ileum and rat uterus, but not the bradykinin-induced relaxation of pre-contracted ileum, whereas BPP9a and enalaprilat potentiated both bradykinin effects. The receptor mediating both the contraction and the relaxation elicited by bradykinin in the ileum was found to be of the B2 type. KPP retained its potentiating effect in the presence of enalaprilat in the guinea-pig ileum and rat uterus, whereas the potentiation evoked by BPP9a was abolished. Enalaprilat inhibited the activity of purified ACE, whereas KPP was completely devoid of such an effect. The potentiating effect of KPP, but not that of BPP9a or enalaprilat, was blocked by compounds that inhibit phospholipase A2 and lipoxygenase activity but not by inhibitors of cyclo-oxygenase or phosphodiesterases. The results suggest that the potentiating effect of KPP (i) does not involve inhibition of ACE; (ii) is not due to an increased affinity of the receptor for bradykinin, and (iii) probably involves post-receptor events linked to phospholipase A2 and to the lipoxygenase pathway.

  16. The influence of angiotensin converting enzyme and bradykinin receptor B2 gene variants on voluntary fluid intake and fluid balance in healthy men during moderate-intensity exercise in the heat.

    PubMed

    Yau, Adora M W; Moss, Andrew D; James, Lewis John; Gilmore, William; Ashworth, Jason J; Evans, Gethin H

    2015-02-01

    Angiotensin converting enzyme (ACE) and bradykinin receptor B2 (B2R) genetic variation may affect thirst because of effects on angiotensin II production and bradykinin activity, respectively. To examine this, 45 healthy Caucasian men completed 60 min of cycle exercise at 62% ± 5% peak oxygen uptake in a room heated to 30.5 ± 0.3 °C with ad libitum fluid intake. Blood samples were collected pre-, mid-, and immediately post-cycle. Fluid intake, body mass loss (BML), sweat loss (determined via changes in body mass and fluid intake), and thirst sensation were recorded. All participants were genotyped for the ACE insert fragment (I) and the B2R insert sequence (P). Participants were homozygous for the wild-type allele (WW or MM), heterozygous (WI or MP) or homozygous for the insert (II or PP). No differences between genotype groups were found in mean (±SD) voluntary fluid intake (WW: 613 ± 388, WI: 753 ± 385, II: 862 ± 421 mL, p = 0.31; MM: 599 ± 322, MP: 745 ± 374, PP: 870 ± 459 mL, p = 0.20), percentage BML or any other fluid balance variables for both the ACE and B2R genes, respectively. Mean thirst perception in the B2R PP group, however, was higher (p < 0.05) than both MM and MP at 30, 45, and 60 min. In conclusion, the results of this study suggest that voluntary fluid intake and fluid balance in healthy men performing 60 min of moderate-intensity exercise in the heat are not predominantly influenced by ACE or B2R genetic variation.

  17. SULT2B1b sulfotransferase: induction by vitamin D receptor and reduced expression in prostate cancer.

    PubMed

    Seo, Young-Kyo; Mirkheshti, Nooshin; Song, Chung S; Kim, Soyoung; Dodds, Sherry; Ahn, Soon C; Christy, Barbara; Mendez-Meza, Rosario; Ittmann, Michael M; Abboud-Werner, Sherry; Chatterjee, Bandana

    2013-06-01

    An elevated tumor tissue androgen level, which reactivates androgen receptor in recurrent prostate cancer, arises from the intratumor synthesis of 5α-dihydrotestosterone through use of the precursor steroid dehydroepiandrosterone (DHEA) and is fueled by the steroidogenic enzymes 3β-hydroxysteroid dehydrogenase (3β-HSD1), aldoketoreductase (AKR1C3), and steroid 5-alpha reductase, type 1 (SRD5A1) present in cancer tissue. Sulfotransferase 2B1b (SULT2B1b) (in short, SULT2B) is a prostate-expressed hydroxysteroid SULT that converts cholesterol, oxysterols, and DHEA to 3β-sulfates. DHEA metabolism involving sulfonation by SULT2B can potentially interfere with intraprostate androgen synthesis due to reduction of free DHEA pool and, thus, conversion of DHEA to androstenedione. Here we report that in prostatectomy specimens from treatment-naive patients, SULT2B expression is markedly reduced in malignant tissue (P < .001, Mann-Whitney U test) compared with robust expression in adjacent nonmalignant glands. SULT2B was detected in formalin-fixed specimens by immunohistochemistry on individual sections and tissue array. Immunoblotting of protein lysates of frozen cancer and matched benign tissue confirmed immunohistochemistry results. An in-house-developed rabbit polyclonal antibody against full-length human SULT2B was validated for specificity and used in the analyses. Ligand-activated vitamin D receptor induced the SULT2B1 promoter in vivo in mouse prostate and increased SULT2B mRNA and protein levels in vitro in prostate cancer cells. A vitamin D receptor/retinoid X receptor-α-bound DNA element (with a DR7 motif) mediated induction of the transfected SULT2B1 promoter in calcitriol-treated cells. SULT2B knockdown caused an increased proliferation rate of prostate cancer cells upon stimulation by DHEA. These results suggest that the tumor tissue SULT2B level may partly control prostate cancer growth, and its induction in a therapeutic setting may inhibit disease

  18. Bradykinin-related peptides (BRPs) from skin secretions of three genera of phyllomedusine leaf frogs and their comparative pharmacological effects on mammalian smooth muscles.

    PubMed

    Jiang, Yingchun; Xi, Xinping; Ge, Lilin; Yang, Nan; Hou, Xiaojuan; Ma, Jie; Ma, Chengbang; Wu, Yuxin; Guo, Xiaoxiao; Li, Renjie; Zhou, Mei; Wang, Lei; Chen, Tianbao; Shaw, Chris

    2014-02-01

    While bradykinin has been identified in the skin secretions from several species of amphibian, bradykinin-related peptides (BRPs) are more common constituents. These peptides display a plethora of primary structural variations from the type peptide which include single or multiple amino acid substitutions, N- and/or C-terminal extensions and post-translational modifications such as proline hydroxylation and tyrosine sulfation. Such modified peptides have been reported in species from many families, including Bombinatoridae, Hylidae and Ranidae. The spectrum of these peptides in a given species is thought to be reflective of its predator profile from different vertebrate taxa. Here we report the isolation of BRPs and parallel molecular cloning of their respective biosynthetic precursor-encoding cDNAs from the skin secretions of the Mexican leaf frog (Pachymedusa dacnicolor), the Central American red-eyed leaf frog (Agalychnis callidryas) and the South American orange-legged leaf frog (Phyllomedusa hypochondrialis). Additionally, the eight different BRPs identified were chemically synthesized and screened for bioactivity using four different mammalian smooth muscle preparations and their effects and rank potencies were found to be radically different in these with some acting preferentially through bradykinin B1-type receptors and others through B(2)-type receptors.

  19. Bradykinin and histamine-induced cytosolic calcium increase in capillary endothelial cells of bovine adrenal medulla.

    PubMed

    Vinet, Raúl; Cortés, Magdalena P; Alvarez, Rocío; Delpiano, Marco A

    2014-09-01

    We have assessed the effect of bradykinin and histamine on the cytosolic free calcium concentration ([Ca(2+)]i ) of bovine adrenal medulla capillary endothelial cells (BAMCECs). To measure [Ca(2+)]i changes in BAMCECs the intracellular fluorescent probe, fluo-3 AM, was used. Bradykinin (3 µM) produced a transient monophasic increase in [Ca(2+)]i , which was depressed by B1650 (0.1 µM), a B2-bradykinin receptor antagonist (D-Arg-[Hyp(3), Thi(5,8) , D-Phe(7)]-Bradykinin). Similarly, increase in [Ca(2+)]i induced by histamine was also depressed by tripolidine (0.1 µM), an H1-histamine receptor antagonist. [Ca(2+)]i increase induced by both agonists was unaffected in the absence of extracellular Ca(2+) or presence of antagonists of voltage operated Ca(2+) channels (VOCCs). Thapsigargin (1 µM) did not abolish the increase of [Ca(2+)]i produced by bradykinin, but abolished that of histamine. In contrast, caffeine (100 µM), abolished the [Ca(2+)]i response induced by bradykinin (3 µM), but did not affect the [Ca(2+)]i increase induced by histamine (100 µM). The results indicate the presence of B2 bradykinin- and H1 histamine-receptors in BAMCECs. Liberation of Ca(2+) induced by both agonists occurs through 2 different intracellular mechanisms. While bradykinin activates a sarco(endo) plasmic reticulum (SER) containing a SER Ca(2+) -ATPase (SERCA) thapsigargin-insensitive, histamine activates a SER containing a SERCA thapsigargin-sensitive. We suggest that the increase in [Ca(2+)]i induced by bradykinin and histamine could be of physiological relevance, modulating adrenal gland microcirculation.

  20. Allosteric Inhibition of a Semaphorin 4D Receptor Plexin B1 by a High-Affinity Macrocyclic Peptide.

    PubMed

    Matsunaga, Yukiko; Bashiruddin, Nasir K; Kitago, Yu; Takagi, Junichi; Suga, Hiroaki

    2016-11-17

    Semaphorin axonal guidance factors are multifunctional proteins that play important roles in immune response, cancer cell proliferation, and organogenesis, making semaphorins and their signaling receptor plexins important drug targets for various diseases. However, the large and flat binding surface of the semaphorin-plexin interaction interface is difficult to target by traditional small-molecule drugs. Here, we report the discovery of a high-affinity plexin B1 (PlxnB1)-binding macrocyclic peptide, PB1m6 (KD = 3.5 nM). PB1m6 specifically inhibited the binding of physiological ligand semaphorin 4D (Sema4D) in vitro and completely suppressed Sema4D-induced cell collapse. Structural studies revealed that PB1m6 binds at a groove between the fifth and sixth blades of the sema domain in PlxnB1 distant from the Sema4D-binding site, indicating the non-competitive and allosteric nature of the inhibitory activity. The discovery of this novel allosteric site can potentially be used to target plexin family proteins for the development of drugs that modulate semaphorin and plexin signaling.

  1. Bradykinin Release Avoids High Molecular Weight Kininogen Endocytosis

    PubMed Central

    Nascimento, Fabio D.; Souza, Daianne S. P.; Araujo, Mariana S.; Souza, Sinval E. G.; Sampaio, Misako U.; Nader, Helena B.; Tersariol, Ivarne L. S.; Motta, Guacyara

    2015-01-01

    Human H-kininogen (120 kDa) plays a role in many pathophysiological processes and interacts with the cell surface through protein receptors and proteoglycans, which mediate H-kininogen endocytosis. In the present work we demonstrate that H-kininogen containing bradykinin domain is internalized and different endogenous kininogenases are present in CHO-K1 cells. We used CHO-K1 (wild type) and CHO-745 (mutant deficient in proteoglycans biosynthesis) cell lines. H-kininogen endocytosis was studied using confocal microscopy, and its hydrolysis by cell lysate fraction was determined by immunoblotting. Bradykinin release was also measured by radioimmunoassay. H-kininogen interaction with the cell surface of CHO-745 cells resulted in bradykinin release by serine proteases. In CHO-K1 cells, which produce heparan and chondroitin sulfate proteoglycans, internalization of H-kininogen through its bradykinin domain can occur on lipid raft domains/caveolae. Nevertheless bradykinin-free H-kininogen was not internalized by CHO-K1 cells. The H-kininogen present in acidic endosomal vesicles in CHO-K1 was approximately 10-fold higher than the levels in CHO-745. CHO-K1 lysate fractions were assayed at pH 5.5 and intact H-kininogen was totally hydrolyzed into a 62 kDa fragment. By contrast, at an assay pH 7.4, the remained fragments were 115 kDa, 83 kDa, 62 kDa and 48 kDa in size. The antipain-Sepharose chromatography separated endogenous kininogenases from CHO-K1 lysate fraction. No difference was detected in the assays at pH 5.5 or 7.4, but the proteins in the fraction bound to the resin released bradykinin from H-kininogen. However, the proteins in the unbound fraction cleaved intact H-kininogen at other sites but did not release bradykinin. H-kininogen can interact with extravascular cells, and is internalized dependent on its bradykinin domain and cell surface proteoglycans. After internalization, H-kininogen is proteolytically processed by intracellular kininogenases. The present

  2. TGF-α/HA complex promotes tympanic membrane keratinocyte migration and proliferation via ErbB1 receptor

    SciTech Connect

    Mei Teh, Bing; Redmond, Sharon L.; Shen, Yi; Atlas, Marcus D.; Marano, Robert J.; Dilley, Rodney J.

    2013-04-01

    Tympanic membrane perforations are common and represent a management challenge to clinicians. Current treatments for chronic perforations involve a graft surgery and require general anaesthesia, including associated costs and morbidities. Bioactive molecules (e.g. growth factors, cytokines) play an important role in promoting TM wound healing following perforation and the use of growth factors as a topical treatment for tympanic membrane perforations has been suggested as an alternative to surgery. However, the choice of bioactive molecules best suited to promote wound healing has yet to be identified. We investigated the effects of hyaluronic acid, vitronectin, TGF-α, IL-24 and their combinations on migration, proliferation and adhesion of cultured human tympanic membrane-derived keratinocytes (hTM), in addition to their possible mechanisms of action. We found that TGF-α, TGF-α/HA and TGF-α/IL-24 promoted wound healing by significantly increasing both migration and proliferation. TGF-α and/or HA treated cells showed comparable cell–cell adhesion whilst maintaining an epithelial cell phenotype. With the use of receptor binding inhibitors for ErbB1 (AG1478) and CD44 (BRIC235), we revealed that the activation of ErbB1 is required for TGF-α/HA-mediated migration and proliferation. These results suggest factors that may be incorporated into a tissue-engineered membrane or directly as topical treatment for tympanic membrane perforations and hence reduce the need for a surgery. - Highlights: ► TGF-α, TGF-α/HA and TGF-α/IL-24 improved hTM keratinocyte migration and proliferation. ► TGF-α and/or HA maintained epithelial cell phenotype. ► TGF-α/HA-mediated migration and proliferation requires activation of ErbB1 receptor.

  3. Exploring the link between scavenger receptor B1 expression and chronic obstructive pulmonary disease pathogenesis.

    PubMed

    Valacchi, Giuseppe; Maioli, Emanuela; Sticozzi, Claudia; Cervellati, Franco; Pecorelli, Alessandra; Cervellati, Carlo; Hayek, Joussef

    2015-03-01

    Chronic obstructive pulmonary disease (COPD) has been recognized as one of the major causes of morbidity and mortality in the United States; it is the third leading cause of deaths in the United States, with approximately 15 million Americans affected with COPD. Although exposure to cigarette smoke has been shown to be the main, if not the only, risk factor for COPD, the mechanisms underlying this association remain unclear. Most smokers do not develop COPD, suggesting that a combination of exposure and susceptibility (genetic background) is required. Several mechanisms contribute to the pathogenesis of COPD, such as influx of inflammatory cells into the lung, imbalance between proteolytic and antiproteolytic molecules, disruption of the balance between apoptosis and replenishment of structural cells in the lung, and disruption of oxidant/antioxidant balance. The scavenger receptor BI (SRB1) plays an important role in mediating the uptake of high-density lipoprotein (HDL)-derived cholesterol and cholesteryl ester in tissues. In addition to its role as the HDL receptor, SRB1 is also involved in pathogen recognition, identification of apoptotic cells, tissue antioxidant uptake (tocopherol and carotenoids), and lung surfactant composition, all factors involved in COPD pathogenesis. Therefore, it is possible that lung SRB1 levels are involved in the development of COPD.

  4. Characterisation and mechanisms of bradykinin-evoked pain in man using iontophoresis

    PubMed Central

    Paterson, Kathryn J.; Zambreanu, Laura; Bennett, David L.H.; McMahon, Stephen B.

    2013-01-01

    Bradykinin (BK) is an inflammatory mediator that can evoke oedema and vasodilatation, and is a potent algogen signalling via the B1 and B2 G-protein coupled receptors. In naïve skin, BK is effective via constitutively expressed B2 receptors (B2R), while B1 receptors (B1R) are purported to be upregulated by inflammation. The aim of this investigation was to optimise BK delivery to investigate the algesic effects of BK and how these are modulated by inflammation. BK iontophoresis evoked dose- and temperature-dependent pain and neurogenic erythema, as well as thermal and mechanical hyperalgesia (P < 0.001 vs saline control). To differentiate the direct effects of BK from indirect effects mediated by histamine released from mast cells (MCs), skin was pretreated with compound 4880 to degranulate the MCs prior to BK challenge. The early phase of BK-evoked pain was reduced in degranulated skin (P < 0.001), while thermal and mechanical sensitisation, wheal, and flare were still evident. In contrast to BK, the B1R selective agonist des-Arg9-BK failed to induce pain or sensitise naïve skin. However, following skin inflammation induced by ultraviolet B irradiation, this compound produced a robust pain response. We have optimised a versatile experimental model by which BK and its analogues can be administered to human skin. We have found that there is an early phase of BK-induced pain which partly depends on the release of inflammatory mediators by MCs; however, subsequent hyperalgesia is not dependent on MC degranulation. In naïve skin, B2R signaling predominates, however, cutaneous inflammation results in enhanced B1R responses. PMID:23422725

  5. Bradykinin stimulation of phosphoinositide hydrolysis in guinea-pig ileum longitudinal muscle.

    PubMed Central

    Ransom, R. W.; Goodman, C. B.; Young, G. S.

    1992-01-01

    1. Bradykinin (BK)-induced contraction of ileal smooth muscle is assumed to be due to phosphoinositide hydrolysis but this has never been reported. We have investigated whether BK receptors are linked to this transduction mechanism in guinea-pig ileum longitudinal muscle and determined whether these receptors are equivalent to those labelled in [3H]-BK binding assays. 2. In membranes prepared from longitudinal muscle, [3H]-BK bound to a single class of sites with high affinity. Characterization of the binding with BK analogues indicated that the radioligand selectivity labelled a B2 type receptor. 3. BK significantly elevated tissue levels of [3H]-inositol phosphates in longitudinal muscle slices preincubated with [3H]-myo-inositol. The agonists potencies of BK, Lys-BK, Met-Lys-BK, Tyr5-BK and Tyr8-BK were in agreement with their relative potencies in the binding assay. The B1 receptor agonist des-Arg9-BK, did not stimulate inositol phosphate production. The response to BK was blocked by known B2 receptor antagonists but not by the B1 antagonist des-Arg9, Leu8-BK. 4. BK-induced phosphoinositide hydrolysis was unaffected by exposure of muscle slices to either atropine or indomethacin. 5. The results indicate that the B2 receptors linked to phosphoinositide turnover in ileal longitudinal muscle exhibit properties similar to those involved in contractile responses. Also, the receptor mediating the phosphoinositide response is likely to be that labelled in the [3H]-BK binding studies. PMID:1324057

  6. The expression of GABA(B1) and GABA(B2) receptor subunits in the cNS differs from that in peripheral tissues.

    PubMed

    Calver, A R; Medhurst, A D; Robbins, M J; Charles, K J; Evans, M L; Harrison, D C; Stammers, M; Hughes, S A; Hervieu, G; Couve, A; Moss, S J; Middlemiss, D N; Pangalos, M N

    2000-01-01

    GABA(B) receptors are G-protein-coupled receptors that mediate the slow and prolonged synaptic actions of GABA in the CNS via the modulation of ion channels. Unusually, GABA(B) receptors form functional heterodimers composed of GABA(B1) and GABA(B2) subunits. The GABA(B1) subunit is essential for ligand binding, whereas the GABA(B2) subunit is essential for functional expression of the receptor dimer at the cell surface. We have used real-time reverse transcriptase-polymerase chain reaction to analyse expression levels of these subunits, and their associated splice variants, in the CNS and peripheral tissues of human and rat. GABA(B1) subunit splice variants were expressed throughout the CNS and peripheral tissues, whereas surprisingly GABA(B2) subunit splice variants were neural specific. Using novel antisera specific to individual GABA(B) receptor subunits, we have confirmed these findings at the protein level. Analysis by immunoblotting demonstrated the presence of the GABA(B1) subunit, but not the GABA(B2) subunit, in uterus and spleen. Furthermore, we have shown the first immunocytochemical analysis of the GABA(B2) subunit in the brain and spinal cord using a GABA(B2)-specific antibody. We have, therefore, identified areas of non-overlap between GABA(B1) and GABA(B2) subunit expression in tissues known to contain functional GABA(B) receptors. Such areas are of interest as they may well contain novel GABA(B) receptor subunit isoforms, expression of which would enable the GABA(B1) subunit to reach the cell surface and form functional GABA(B) receptors.

  7. Bradykinin promotes TLR2 expression in human gingival fibroblasts.

    PubMed

    Gutiérrez-Venegas, Gloria; Arreguín-Cano, Juan Antonio

    2011-12-01

    Bradykinin (BK) is implicated in the sensation of pain, vasodilation, increases in vascular permeability and pathogenic processes associated with inflammation. Studies have shown that BK promotes the intracellular movement of calcium in human gingival fibroblasts by binding to the B2 receptor. In this study we investigated the effect of BK on regulation of Toll-like receptor 2 (TLR2) expression. Our results show that BK stimulates TLR2 receptor transcription and translation by activation of protein kinase C as well as AKT. Our study contributes important information on the regulation and expression of molecules that promote chronic inflammatory processes, which lead to periodontitis and consequently to loss of the dental organ.

  8. Effects of the 5-HT receptor antagonists GR127935 (5-HT1B/1D) and MDL100907 (5-HT2A) in the consolidation of learning.

    PubMed

    Meneses, A; Terrón, J A; Hong, E

    1997-12-01

    We have previously reported that 5-HT1B/1D and 5-HT2A/2B/2C receptors play a role in learning and memory. The present investigation was devoted to analyze further in the autoshaping learning task: (1) the effects of the 5-HT1A/1B/1D receptor agonist, GR46611, the 5-HT1B/1D receptor antagonist, GR127935, and the selective 5-HT2A receptor antagonist, MDL100907. Consistent with a role of 5-HT1B/1D receptors in learning, the post-training injection of GR46611 (1-10 mg/kg) decreased the consolidation of learning whereas GR127935 (10 mg/kg) increased it; the effects of both drugs were reversed by PCA pretreatment. GR127935 abolished the decrease induced by GR46611, TFMPP and mCPP, whereas MDL100907 (0.1-3.0 mg/kg) had no effect by itself but abolished the effects of DOI, ketanserin and TFMPP and moderately inhibited the effects elicited by mCPP, 1-NP and mesulergine. Neither did GR127935 nor MDL100907 significantly modify the increase in the consolidation of learning induced by 8-OH-DPAT. Thus, the present findings suggest that stimulation of presynaptic 5-HT1B/1D receptors impairs the consolidation of learning whilst stimulation of 5-HT2A/2C receptors enhances it; the blockade of 5-HT2A receptors has no effects. In addition, 5-HT2 receptors seem to modulate this cognitive stage.

  9. Cardiovascular actions of lungfish bradykinin in the unanaesthetised African lungfish, Protopterus annectens.

    PubMed

    Balment, Richard J; Masini, Maria A; Vallarino, Mauro; Conlon, J Michael

    2002-02-01

    Bradykinin (BK) isolated from plasma of the African lungfish, Protopterus annectens, contains four amino acid substitutions compared with BK from mammals (Arg(1)-->Tyr, Pro(2)-->Gly, Pro(7)-->Ala, Phe(8)-->Pro). Bolus intra-arterial injections of synthetic lungfish BK (1-1000 pmol/kg body wt.) into unanaesthetised, juvenile lungfish (n=5) produced a dose-dependent increase in arterial blood pressure and pulse pressure. The maximum pressor response occurred 2-3 min after injection and persisted for up to 15 min. The threshold dose producing a significant (P<0.01) rise in pressure was 50 pmol/kg and the maximum increase, following injection of 300 pmol/kg, was 9.3 +/- 2.3 mmHg. Injection of the higher doses of lungfish BK produced a significant (P<0.05) increase in heart rate (2.8 +/- 0.8 beats/min at 100 pmol/kg). In contrast, bolus intra-arterial injections of mammalian BK, in doses up to 1000 pmol/kg, produced no significant cardiovascular effects in the lungfish. The data support the existence of a functioning kallikrein-kinin system in the lungfish and demonstrate that the ligand-binding properties of the receptor(s) mediating the cardiovascular actions of lungfish BK are appreciably different from mammalian B1 and B2 receptors.

  10. The physiological expression of scavenger receptor SR-B1 in canine endometrial and placental epithelial cells and its potential involvement in pathogenesis of pyometra.

    PubMed

    Gabriel, C; Becher-Deichsel, A; Hlavaty, J; Mair, G; Walter, I

    2016-06-01

    Pyometra, the purulent inflammation of the uterus, is a common uterine disease of bitches that has potentially life-threatening consequences. The opportunistic bacterial infection of the uterus often progresses into the serious systemic inflammatory response syndrome. In a previous study, we characterized epithelial foam cells in the canine endometrial surface occurring in metestrus, and we regularly observed pronounced epithelial foam-cell formations in pyometra-affected uteri. Therefore, it was assumed that the mechanism behind lipid droplet accumulation in surface epithelial cells might even increase bacterial binding capacity and promote pyometra development. Lipid droplet accumulation in epithelial cells is accomplished via specialized lipid receptors called scavenger receptors (SR). Scavenger receptor class B type 1 (SR-B1) is an important receptor for lipid accumulation in diverse cell types, but it is also a strong binding partner for bacteria, and thereby enhances bacterial adhesion and clinical signs of systemic inflammatory response syndrome. In the present study, after the isolation of metestrous surface epithelial cells from canine uteri by laser capture microdissection, SR-B1 was identified at the messenger RNA (mRNA) level by quantitative real time polymerase chain reaction and also at the protein level by means of immunohistochemistry. In pyometra-affected uteri, SR-B1 mRNA expression was higher than that in the healthy control samples, and SR-B1 protein was expressed in the surface and crypt epithelial cells. Furthermore, to understand the physiological role of SR-B1 expression in the metestrus surface epithelial cells, we investigated its expression in the epithelial cells of the glandular chambers of canine placenta in different stages of gestation because these cells are also characterized by lipid droplet accumulation. SR-B1 was present in the placental epithelial cells of the glandular chambers from 25 to 30 and 45 to 50 days of gestation

  11. Induction of selective blood-tumor barrier permeability and macromolecular transport by a biostable kinin B1 receptor agonist in a glioma rat model.

    PubMed

    Côté, Jérôme; Bovenzi, Veronica; Savard, Martin; Dubuc, Céléna; Fortier, Audrey; Neugebauer, Witold; Tremblay, Luc; Müller-Esterl, Werner; Tsanaclis, Ana-Maria; Lepage, Martin; Fortin, David; Gobeil, Fernand

    2012-01-01

    Treatment of malignant glioma with chemotherapy is limited mostly because of delivery impediment related to the blood-brain tumor barrier (BTB). B1 receptors (B1R), inducible prototypical G-protein coupled receptors (GPCR) can regulate permeability of vessels including possibly that of brain tumors. Here, we determine the extent of BTB permeability induced by the natural and synthetic peptide B1R agonists, LysdesArg(9)BK (LDBK) and SarLys[dPhe(8)]desArg(9)BK (NG29), in syngeneic F98 glioma-implanted Fischer rats. Ten days after tumor inoculation, we detected the presence of B1R on tumor cells and associated vasculature. NG29 infusion increased brain distribution volume and uptake profiles of paramagnetic probes (Magnevist and Gadomer) at tumoral sites (T(1)-weighted imaging). These effects were blocked by B1R antagonist and non-selective cyclooxygenase inhibitors, but not by B2R antagonist and non-selective nitric oxide synthase inhibitors. Consistent with MRI data, systemic co-administration of NG29 improved brain tumor delivery of Carboplatin chemotherapy (ICP-Mass spectrometry). We also detected elevated B1R expression in clinical samples of high-grade glioma. Our results documented a novel GPCR-signaling mechanism for promoting transient BTB disruption, involving activation of B1R and ensuing production of COX metabolites. They also underlined the potential value of synthetic biostable B1R agonists as selective BTB modulators for local delivery of different sized-therapeutics at (peri)tumoral sites.

  12. Induction of Selective Blood-Tumor Barrier Permeability and Macromolecular Transport by a Biostable Kinin B1 Receptor Agonist in a Glioma Rat Model

    PubMed Central

    Côté, Jérôme; Bovenzi, Veronica; Savard, Martin; Dubuc, Céléna; Fortier, Audrey; Neugebauer, Witold; Tremblay, Luc; Müller-Esterl, Werner; Tsanaclis, Ana-Maria; Lepage, Martin; Fortin, David; Gobeil, Fernand

    2012-01-01

    Treatment of malignant glioma with chemotherapy is limited mostly because of delivery impediment related to the blood-brain tumor barrier (BTB). B1 receptors (B1R), inducible prototypical G-protein coupled receptors (GPCR) can regulate permeability of vessels including possibly that of brain tumors. Here, we determine the extent of BTB permeability induced by the natural and synthetic peptide B1R agonists, LysdesArg9BK (LDBK) and SarLys[dPhe8]desArg9BK (NG29), in syngeneic F98 glioma-implanted Fischer rats. Ten days after tumor inoculation, we detected the presence of B1R on tumor cells and associated vasculature. NG29 infusion increased brain distribution volume and uptake profiles of paramagnetic probes (Magnevist and Gadomer) at tumoral sites (T1-weighted imaging). These effects were blocked by B1R antagonist and non-selective cyclooxygenase inhibitors, but not by B2R antagonist and non-selective nitric oxide synthase inhibitors. Consistent with MRI data, systemic co-administration of NG29 improved brain tumor delivery of Carboplatin chemotherapy (ICP-Mass spectrometry). We also detected elevated B1R expression in clinical samples of high-grade glioma. Our results documented a novel GPCR-signaling mechanism for promoting transient BTB disruption, involving activation of B1R and ensuing production of COX metabolites. They also underlined the potential value of synthetic biostable B1R agonists as selective BTB modulators for local delivery of different sized-therapeutics at (peri)tumoral sites. PMID:22629405

  13. Functional Pairing of Class B1 Ligand-GPCR in Cephalochordate Provides Evidence of the Origin of PTH and PACAP/Glucagon Receptor Family

    PubMed Central

    On, Jason S.W.; Duan, Cumming; Chow, Billy K.C.; Lee, Leo T.O.

    2015-01-01

    Several hypotheses have been proposed regarding the origin and evolution of the secretin family of peptides and receptors. However, identification of homologous ligand–receptor pairs in invertebrates and vertebrates is difficult because of the low levels of sequence identity between orthologs of distant species. In this study, five receptors structurally related to the vertebrate class B1 G protein-coupled receptor (GPCR) family were characterized from amphioxus (Branchiostoma floridae). Phylogenetic analysis showed that they clustered with vertebrate parathyroid hormone receptors (PTHR) and pituitary adenylate cyclase-activating polypeptide (PACAP)/glucagon receptors. These PTHR-like receptors shared synteny with several PTH and PACAP/glucagon receptors identified in spotted gar, Xenopus, and human, indicating that amphioxus preserves the ancestral chordate genomic organization of these receptor subfamilies. According to recent data by Mirabeau and Joly, amphioxus also expresses putative peptide ligands including homologs of PTH (bfPTH1 and 2) and PACAP/GLUC-like peptides (bfPACAP/GLUCs) that may interact with these receptors. Functional analyses showed that bfPTH1 and bfPTH2 activated one of the amphioxus receptors (bf98C) whereas bfPACAP/GLUCs strongly interacted with bf95. In summary, our data confirm the presence of PTH and PACAP/GLUC ligand–receptor pairs in amphioxus, demonstrating that functional homologs of vertebrate PTH and PACAP/glucagon GPCR subfamilies arose before the cephalochordate divergence from the ancestor of tunicates and vertebrates. PMID:25841489

  14. Functional Pairing of Class B1 Ligand-GPCR in Cephalochordate Provides Evidence of the Origin of PTH and PACAP/Glucagon Receptor Family.

    PubMed

    On, Jason S W; Duan, Cumming; Chow, Billy K C; Lee, Leo T O

    2015-08-01

    Several hypotheses have been proposed regarding the origin and evolution of the secretin family of peptides and receptors. However, identification of homologous ligand-receptor pairs in invertebrates and vertebrates is difficult because of the low levels of sequence identity between orthologs of distant species. In this study, five receptors structurally related to the vertebrate class B1 G protein-coupled receptor (GPCR) family were characterized from amphioxus (Branchiostoma floridae). Phylogenetic analysis showed that they clustered with vertebrate parathyroid hormone receptors (PTHR) and pituitary adenylate cyclase-activating polypeptide (PACAP)/glucagon receptors. These PTHR-like receptors shared synteny with several PTH and PACAP/glucagon receptors identified in spotted gar, Xenopus, and human, indicating that amphioxus preserves the ancestral chordate genomic organization of these receptor subfamilies. According to recent data by Mirabeau and Joly, amphioxus also expresses putative peptide ligands including homologs of PTH (bfPTH1 and 2) and PACAP/GLUC-like peptides (bfPACAP/GLUCs) that may interact with these receptors. Functional analyses showed that bfPTH1 and bfPTH2 activated one of the amphioxus receptors (bf98C) whereas bfPACAP/GLUCs strongly interacted with bf95. In summary, our data confirm the presence of PTH and PACAP/GLUC ligand-receptor pairs in amphioxus, demonstrating that functional homologs of vertebrate PTH and PACAP/glucagon GPCR subfamilies arose before the cephalochordate divergence from the ancestor of tunicates and vertebrates.

  15. Ah receptor, CYP1A1, CYP1A2 and CYP1B1 gene polymorphisms are not involved in the risk of recurrent pregnancy loss.

    PubMed

    Saijo, Y; Sata, F; Yamada, H; Suzuki, K; Sasaki, S; Kondo, T; Gong, Y Y; Kato, E H; Shimada, S; Morikawa, M; Minakami, H; Kishi, R

    2004-10-01

    The etiology of recurrent pregnancy loss (RPL) remains unclear, but it may be related to a possible genetic predisposition together with involvement of environmental factors. We examined the relation between RPL and polymorphisms in four genes, human aryl hydrocarbon (Ah) receptor, cytochrome P450 (CYP) 1A1, CYP1A2 and CYP1B1, which are involved in the metabolism of a wide range of environmental toxins and carcinogens. All cases and controls were women resident in Sapporo, Japan and the surrounding area. The Ah receptor, CYP1A1, CYP1A2 and CYP1B1 genotypes were assessed in 113 Japanese women with recurrent pregnancy loss (RPL) and 203 ethnically matched women experiencing at least one live birth and no spontaneous abortion (control). No significant differences in Ah receptor, CYP1A1, CYP1A2 and CYP1B1 genotype frequencies were found between the women with RPL and the controls [Ah receptor: Arg/Arg (reference); Arg/Lys and Lys/Lys, odds ratio (OR)=0.67; 95% confidence interval (CI)=0.40-1.11, CYP1A1: m1m1 (reference); m1m2 and m2m2, OR = 0.86; 95% CI = 0.53-1.40, CYP1A2: C/C and C/A (reference); A/A, OR = 1.16; 95% CI = 0.71-1.88, CYP1B1: Leu/Leu (reference); Leu/Val and Val/Val, OR = 1.18; 95% CI = 0.68-2.02]. The present study suggests that the Ah receptor, CYP1A1, CYP1A2 and CYP1B1 gene polymorphisms are not major genetic regulators in RPL.

  16. Role of spinal 5-HT5A, and 5-HT1A/1B/1D, receptors in neuropathic pain induced by spinal nerve ligation in rats.

    PubMed

    Avila-Rojas, Sabino Hazael; Velázquez-Lagunas, Isabel; Salinas-Abarca, Ana Belen; Barragán-Iglesias, Paulino; Pineda-Farias, Jorge Baruch; Granados-Soto, Vinicio

    2015-10-05

    Serotonin (5-HT) participates in pain modulation by interacting with different 5-HT receptors. The role of 5-HT5A receptor in neuropathic pain has not previously studied. The purpose of this study was to investigate: A) the role of 5-HT5A receptors in rats subjected to spinal nerve injury; B) the expression of 5-HT5A receptors in dorsal spinal cord and dorsal root ganglia (DRG). Neuropathic pain was induced by L5/L6 spinal nerve ligation. Tactile allodynia in neuropathic rats was assessed with von Frey filaments. Western blot methodology was used to determine 5-HT5A receptor protein expression. Intrathecal administration (on day 14th) of 5-HT (10-100 nmol) or 5-carboxamidotryptamine (5-CT, 0.03-0.3 nmol) reversed nerve injury-induced tactile allodynia. Intrathecal non-selective (methiothepin, 0.1-0.8 nmol) and selective (SB-699551, 1-10 nmol) 5-HT5A receptor antagonists reduced, by ~60% and ~25%, respectively, the antiallodynic effect of 5-HT (100 nmol) or 5-CT (0.3 nmol). Moreover, both selective 5-HT1A and 5-HT1B/1D receptor antagonists, WAY-100635 (0.3-1 nmol) and GR-127935 (0.3-1 nmol), respectively, partially diminished the antiallodynic effect of 5-HT or 5-CT by about 30%. Injection of antagonists, by themselves, did not affect allodynia. 5-HT5A receptors were expressed in the ipsilateral dorsal lumbar spinal cord and DRG and L5/L6 spinal nerve ligation did not modify 5-HT5A receptor protein expression in those sites. Results suggest that 5-HT5A receptors reduce pain processing in the spinal cord and that 5-HT and 5-CT reduce neuropathic pain through activation of 5-HT5A and 5-HT1A/1B/1D receptors. These receptors could be an important part of the descending pain inhibitory system.

  17. Metformin suppresses CYP1A1 and CYP1B1 expression in breast cancer cells by down-regulating aryl hydrocarbon receptor expression

    SciTech Connect

    Do, Minh Truong; Kim, Hyung Gyun; Tran, Thi Thu Phuong; Khanal, Tilak; Choi, Jae Ho; Chung, Young Chul; Jeong, Tae Cheon; Jeong, Hye Gwang

    2014-10-01

    Induction of cytochrome P450 (CYP) 1A1 and CYP1B1 by environmental xenobiotic chemicals or endogenous ligands through the activation of the aryl hydrocarbon receptor (AhR) has been implicated in a variety of cellular processes related to cancer, such as transformation and tumorigenesis. Here, we investigated the effects of the anti-diabetes drug metformin on expression of CYP1A1 and CYP1B1 in breast cancer cells under constitutive and inducible conditions. Our results indicated that metformin down-regulated the expression of CYP1A1 and CYP1B1 in breast cancer cells under constitutive and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced conditions. Down-regulation of AhR expression was required for metformin-mediated decreases in CYP1A1 and CYP1B1 expression, and the metformin-mediated CYP1A1 and CYP1B1 reduction is irrelevant to estrogen receptor α (ERα) signaling. Furthermore, we found that metformin markedly down-regulated Sp1 protein levels in breast cancer cells. The use of genetic and pharmacological tools revealed that metformin-mediated down-regulation of AhR expression was mediated through the reduction of Sp1 protein. Metformin inhibited endogenous AhR ligand-induced CYP1A1 and CYP1B1 expression by suppressing tryptophan-2,3-dioxygenase (TDO) expression in MCF-7 cells. Finally, metformin inhibits TDO expression through a down-regulation of Sp1 and glucocorticoid receptor (GR) protein levels. Our findings demonstrate that metformin reduces CYP1A1 and CYP1B1 expression in breast cancer cells by down-regulating AhR signaling. Metformin would be able to act as a potential chemopreventive agent against CYP1A1 and CYP1B1-mediated carcinogenesis and development of cancer. - Graphical abstract: Schematic of the CYP1A1 and CYP1B1 gene regulation by metformin. - Highlights: • Metformin inhibits CYP1A1 and CYP1B1 expression. • Metformin down-regulates the AhR signaling. • Metformin reduces Sp1 protein expression. • Metformin suppresses TDO expression.

  18. Dissociation of bradykinin-induced prostaglandin formation from phosphatidylinositol turnover in Swiss 3T3 fibroblasts: evidence for G protein regulation of phospholipase A/sub 2/

    SciTech Connect

    Burch, R.M.; Axelrod, J.

    1987-09-01

    In Swiss 3T3 fibroblasts bradykinin stimulated inositol phosphate (InsP) formation and prostaglandin E/sub 2/ (PGE/sub 2/) synthesis. The EC/sub 50/ values for stimulation of PGE/sub 2/ synthesis and InsP formation by bradykinin were similar, 200 pM and 275 pM, respectively. Guanosine-5'-(..gamma..-thio)triphosphate stimulated PGE/sub 2/ synthesis and InsP formation, and guanosine-5'-(..beta..-thio)diphosphate inhibited both PGE/sub 2/ synthesis and InsP formation stimulated by bradykinin. Neither bradykinin-stimulated PGE/sub 2/ synthesis nor InsP formation was sensitive to pertussis toxin. Phorbol ester, dexamethasone, and cycloheximide distinguished between bradykinin-stimulated PGE/sub 2/ synthesis and InsP formation. Phorbol 12-myristate 13-acetate enhanced bradykinin-stimulated PGE/sub 2/ synthesis but inhibited bradykinin-stimulated InsP formation. Pretreatment of cells with dexamethasone for 24 hr inhibited bradykinin-stimulated PGE/sub 2/ synthesis but was without effect on bradykinin-stimulated InsP formation. Cycloheximide inhibited on bradykinin-stimulated InsP formation. When bradykinin was added to cells prelabeled with (/sup 3/H) choline, the phospholipase A/sub 2/ products lysophosphatidylcholine and glycerophosphocholine were generated. The data suggest that bradykinin receptors are coupled by GTP-binding proteins to both phospholipase C and phospholipase A/sub 2/ and that phospholipase A/sub 2/ is the enzyme that catalyzes release of arachidonate for prostaglandin synthesis.

  19. Receptor specificity and trigemino-vascular inhibitory actions of a novel 5-HT1B/1D receptor partial agonist, 311C90 (zolmitriptan)

    PubMed Central

    Martin, G R; Robertson, A D; MacLennan, S J; Prentice, D J; Barrett, V J; Buckingham, J; Honey, A C; Giles, H; Moncada, S

    1997-01-01

    311C90 (zolmitriptan zomig: (S)-4[[3-[2-(dimethylamino)ethyl]-1H-indol-5-yl]methyl]-2-oxazolidinone) is a novel 5-HT1B/1D receptor agonist with proven efficacy in the acute treatment of migraine. Here, we describe the receptor specificity of the drug and its actions on trigeminal-evoked plasma protein extravasation into the dura mater of the anaesthetized guinea-pig. At the ‘5-HT1B-like' receptor mediating vascular contraction (rabbit saphenous vein), the compound was a potent (p[A50]=6.79±0.06) partial agonist achieving 77±4% of the maximum effect to 5-hydroxytryptamine (5-HT). In the same experiments, sumatriptan (p[A50]=6.48±0.04) was half as potent as 311C90 and produced 97±2% of the 5-HT maximum effect. Studies in which receptor inactivation methods were used to estimate the affinity (pKA) and efficacy relative to 5-HT (τrel.) for each agonist confirmed that 311C90 exhibits higher affinity than sumatriptan (pKA=6.63±0.04 and 6.16±0.03, respectively) and that both drugs are partial agonists relative to 5-HT (τrel=0.61±0.03 and 0.63±0.10, respectively, compared to 5-HT=1.0). Consistent with its effects in rabbit saphenous vein, 311C90 also produced concentration-dependent contractions of primate basilar artery and human epicardial coronary artery rings. In basilar artery, agonist potency (p[A50]=6.92±0.07) was similar to that demonstrated in rabbit saphenous vein, again being 2–3 fold higher than for sumatriptan (p[A50]=6.46±0.03). Both agonists produced about 50% of the maximum response obtained with 5-HT in the same preparations. In rings of human coronary artery, the absolute potency of 311C90 and sumatriptan was higher than in primate basilar artery (p[A50]=7.3±0.1 and 6.7±0.1, respectively), but maximum effects relative to 5-HT were lower (37±8% and 35±7%, respectively). In both types of vessel, the inability of 5-HT1B/1D agonists to achieve the same maximum as the endogenous agonist 5-HT is explained by the additional presence of 5-HT2A

  20. Pathways for Modulating Exosome Lipids Identified By High-Density Lipoprotein-Like Nanoparticle Binding to Scavenger Receptor Type B-1.

    PubMed

    Angeloni, Nicholas L; McMahon, Kaylin M; Swaminathan, Suchitra; Plebanek, Michael P; Osman, Iman; Volpert, Olga V; Thaxton, C Shad

    2016-03-11

    Exosomes are produced by cells to mediate intercellular communication, and have been shown to perpetuate diseases, including cancer. New tools are needed to understand exosome biology, detect exosomes from specific cell types in complex biological media, and to modify exosomes. Our data demonstrate a cellular pathway whereby membrane-bound scavenger receptor type B-1 (SR-B1) in parent cells becomes incorporated into exosomes. We tailored synthetic HDL-like nanoparticles (HDL NP), high-affinity ligands for SR-B1, to carry a fluorescently labeled phospholipid. Data show SR-B1-dependent transfer of the fluorescent phospholipid from HDL NPs to exosomes. Modified exosomes are stable in serum and can be directly detected using flow cytometry. As proof-of-concept, human serum exosomes were found to express SR-B1, and HDL NPs can be used to label and isolate them. Ultimately, we discovered a natural cellular pathway and nanoparticle-receptor pair that enables exosome modulation, detection, and isolation.

  1. Central nervous system activity associated with the pain evoked by bradykinin and its alteration by morphine and aspirin.

    PubMed

    Lim, R K; Krauthamer, G; Guzman, F; Fulp, R R

    1969-07-01

    Synthetic bradykinin, a nonapeptide formed from alpha-2 globulin in plasma, injected intra-arterially or intraperitoneally in cats in doses of 10-50 mug, evoked activity in the central nervous system in pathways associated with the signaling of pain. Similar injections of bradykinin in intact normal cats and dogs evoked manifestations of pain, and in conscious humans elicited verbal reports of pain perceived in the area of injection. Single unit activity was recorded in the medial reticular formation of the brainstem, in the medial thalamus and, more laterally, among the posterior group nuclei and the suprageniculate nucleus. Bradykinin did not evoke any cortical or subcortical slow potentials such as those evoked by electrical stimulation of the foot pads. When bradykinin was given together with the electrical stimulus, the responses evoked by the latter were blocked. Morphines uppressed bradykinin-evoked activity. Aspirin caused marked fluctuations in activity, unrelated to the bradykinin injection; the bradykinin block of evoked potentials could no longer be observed after aspirin dosage. The results are discussed in terms of the peripheral and central sites of analgesic action and the likelihood of the existence of chemosensitive pain receptors.

  2. CENTRAL NERVOUS SYSTEM ACTIVITY ASSOCIATED WITH PAIN EVOKED BY BRADYKININ AND ITS ALTERATION BY MORPHINE AND ASPIRIN

    PubMed Central

    Lim, R. K. S.; Krauthamer, G.; Guzman, F.; Fulp, R. R.

    1969-01-01

    Synthetic bradykinin, a nonapeptide formed from α-2 globulin in plasma, injected intra-arterially or intraperitoneally in cats in doses of 10-50 μg, evoked activity in the central nervous system in pathways associated with the signaling of pain. Similar injections of bradykinin in intact normal cats and dogs evoked manifestations of pain, and in conscious humans elicited verbal reports of pain perceived in the area of injection. Single unit activity was recorded in the medial reticular formation of the brainstem, in the medial thalamus and, more laterally, among the posterior group nuclei and the suprageniculate nucleus. Bradykinin did not evoke any cortical or subcortical slow potentials such as those evoked by electrical stimulation of the foot pads. When bradykinin was given together with the electrical stimulus, the responses evoked by the latter were blocked. Morphines uppressed bradykinin-evoked activity. Aspirin caused marked fluctuations in activity, unrelated to the bradykinin injection; the bradykinin block of evoked potentials could no longer be observed after aspirin dosage. The results are discussed in terms of the peripheral and central sites of analgesic action and the likelihood of the existence of chemosensitive pain receptors. PMID:5259760

  3. Protein kinase mediated upregulation of endothelin A, endothelin B and 5-hydroxytryptamine 1B/1D receptors during organ culture in rat basilar artery

    PubMed Central

    Hansen-Schwartz, Jacob; Svensson, Carl-Lennart; Xu, Cang-Bao; Edvinsson, Lars

    2002-01-01

    Organ culture has been shown to upregulate both endothelin (ET) and 5-hydroxytryptamine 1B/1D (5-HT1B/1D) receptors in rat cerebral arteries. The purpose of the present study was to investigate the involvement of protein kinases, especially protein kinases C (PKC) and A (PKA) in this process. The effect of inhibiting protein kinases during organ culture with staurosporine (unspecific protein kinase inhitor), RO 31-7549 (specific inhibitor of classical PKC's) and H 89 (specific inhibitor of PKA) was examined using in vitro pharmacological examination of cultured vessel segments with ET-1 (unspecific ETA and ETB agonist), S6c (specific ETB agonist) and 5-CT (5-HT1 agonist). Levels of mRNA coding for the ETA, ETB, 5-HT1B and 5-HT1D receptors were analysed using real-time RT–PCR. Classical PKC's are critically involved in the appearance of the ETB receptor; co-culture with RO 31-7549 abolished the contractile response (6.9±1.8%) and reduced the ETB receptor mRNA by 44±4% as compared to the cultured control. Correlation between decreased ETB receptor mRNA and abolished contractile function indicates upstream involvement of PKC. Inhibition of PKA generally had an enhancing effect on the induced changes giving rise to a 7–25% increase in Emax in response to ET-1, S6c and 5-CT as compared to the cultured control. Staurosporine inhibited the culture induced upregulation of the response of both the ETA and the 5-HT1B/1D receptors, but had no significant effect on the mRNA levels of these receptors. This lack of correlation indicates an additional downstream involvement of protein kinases. PMID:12183337

  4. Antiproliferative effect of the Ginkgo biloba extract is associated with the enhancement of cytochrome P450 1B1 expression in estrogen receptor-negative breast cancer cells.

    PubMed

    Zhao, Xiao-Dan; Dong, Ni; Man, Hong-Tao; Fu, Zhong-Lin; Zhang, Mei-Hong; Kou, Shuang; Ma, Shi-Liang

    2013-09-01

    Ginkgo biloba is a dioecious tree and its extract is a complex mixture that has been used for thousands of years to treat a variety of ailments in traditional Chinese medicine. The aim of this study was to present our observations on the inhibitory effects of different Ginkgo biloba extracts on human breast cancer cell proliferation and growth. Our results demonstrated that treatment of MCF-7 and MDA-MB-231 human breast cancer cells with Ginkgo biloba leaves and ginkgo fruit extract inhibited cell proliferation. It was also observed that this inhibition was accompanied by the enhancement of cytochrome P450 (CYP) 1B1 expression in MDA-MB-231 cells. In addition, treatment with ginkgo fruit extract resulted in a higher CYP1B1 expression in MDA-MB-231 cells compared to treatment with the Ginkgo biloba leaves extract. Our results suggested that the inhibitory effects of the Ginkgo biloba extract on estrogen receptor-negative breast cancer proliferation and the induction of CYP1B1 expression may be exerted through an alternative pathway, independent of the estrogen receptor or the aryl hydrocarbon receptor pathway.

  5. Antiproliferative effect of the Ginkgo biloba extract is associated with the enhancement of cytochrome P450 1B1 expression in estrogen receptor-negative breast cancer cells

    PubMed Central

    ZHAO, XIAO-DAN; DONG, NI; MAN, HONG-TAO; FU, ZHONG-LIN; ZHANG, MEI-HONG; KOU, SHUANG; MA, SHI-LIANG

    2013-01-01

    Ginkgo biloba is a dioecious tree and its extract is a complex mixture that has been used for thousands of years to treat a variety of ailments in traditional Chinese medicine. The aim of this study was to present our observations on the inhibitory effects of different Ginkgo biloba extracts on human breast cancer cell proliferation and growth. Our results demonstrated that treatment of MCF-7 and MDA-MB-231 human breast cancer cells with Ginkgo biloba leaves and ginkgo fruit extract inhibited cell proliferation. It was also observed that this inhibition was accompanied by the enhancement of cytochrome P450 (CYP) 1B1 expression in MDA-MB-231 cells. In addition, treatment with ginkgo fruit extract resulted in a higher CYP1B1 expression in MDA-MB-231 cells compared to treatment with the Ginkgo biloba leaves extract. Our results suggested that the inhibitory effects of the Ginkgo biloba extract on estrogen receptor-negative breast cancer proliferation and the induction of CYP1B1 expression may be exerted through an alternative pathway, independent of the estrogen receptor or the aryl hydrocarbon receptor pathway. PMID:24649031

  6. Role of 5-HT5A and 5-HT1B/1D receptors in the antinociception produced by ergotamine and valerenic acid in the rat formalin test.

    PubMed

    Vidal-Cantú, Guadalupe C; Jiménez-Hernández, Mildred; Rocha-González, Héctor I; Villalón, Carlos M; Granados-Soto, Vinicio; Muñoz-Islas, Enriqueta

    2016-06-15

    Sumatriptan, dihydroergotamine and methysergide inhibit 1% formalin-induced nociception by activation of peripheral 5-HT1B/1D receptors. This study set out to investigate the pharmacological profile of the antinociception produced by intrathecal and intraplantar administration of ergotamine (a 5-HT1B/1D and 5-HT5A/5B receptor agonist) and valerenic acid (a partial agonist at 5-HT5A receptors). Intraplantar injection of 1% formalin in the right hind paw resulted in spontaneous flinching behavior of the injected hindpaw of female Wistar rats. Intrathecal ergotamine (15nmol) or valerenic acid (1 nmol) blocked in a dose dependent manner formalin-induced nociception. The antinociception by intrathecal ergotamine (15nmol) or valerenic acid (1nmol) was partly or completely blocked by intrathecal administration of the antagonists: (i) methiothepin (non-selective 5-HT5A/5B; 0.01-0.1nmol); (ii) SB-699551 (selective 5-HT5A; up to 10nmol); (iii) anti-5-HT5A antibody; (iv) SB-224289 (selective 5-HT1B; 0.1-1nmol); or (v) BRL-15572 (selective 5-HT1D; 0.1-1nmol). Likewise, antinociception by intraplantar ergotamine (15nmol) and valerenic acid (10nmol) was: (i) partially blocked by methiothepin (1nmol), SB-699551 (10nmol) or SB-224289 (1nmol); and (ii) abolished by BRL-15572 (1nmol). The above doses of antagonists (which did not affect per se the formalin-induced nociception) were high enough to completely block their respective receptors. Our results suggest that ergotamine and valerenic acid produce antinociception via 5-HT5A and 5-HT1B/1D receptors located at both spinal and peripheral sites. This provides new evidence for understanding the modulation of nociceptive pathways in inflammatory pain.

  7. Modeling the Effects of HER/ErbB1-3 Coexpression on Receptor Dimerization and Biological Response

    SciTech Connect

    Shankaran, Harish; Wiley, H. S.; Resat, Haluk

    2006-06-01

    The human epidermal growth factor receptor (HER/ErbB) system comprises the epidermal growth factor receptor (EGFR/HER1) and three other homologues viz. HERs2-4. This receptor system plays a critical role in cell proliferation and differentiation. Over-expression of these receptors can be associated with poor prognosis in cancers of the epithelium. It is believed that the dimerization pattern among members of the HER family may play a key role in controlling downstream signaling and the eventual biological response. Here, we examine the effect of co-expressing varying levels of HERs1-3 on the receptor dimerization patterns using mathematical modeling. The model integrates biochemical reactions such as ligand binding, receptor dimerization and phosphorylation with biophysical trafficking reactions to predict the concentrations of activated receptors in various cellular compartments. Our results indicate that co-expression of EGFR with HER2 or HER3 biases signaling to the cell surface and retards signal down-regulation. In addition, simultaneous co-expression of HERs1-3 leads to preferential formation of HER2-HER3 heterodimers, which are known to be potent inducers of cell growth and transformation. We further examined the effect of receptor dimerization patterns on cell phenotype using a simple phenomenological model. Results indicate that co-expression of HER2 and HER3 at low to moderate levels may enable cells to match the phenotype of a high HER2 expresser.

  8. Antidiabetic efficacy of bradykinin antagonist R-954 on glucose tolerance test in diabetic type 1 mice.

    PubMed

    Catanzaro, Orlando L; Dziubecki, Damian; Obregon, Pablo; Rodriguez, Ricardo R; Sirois, Pierre

    2010-04-01

    Insulin-dependent diabetes mellitus (type 1 diabetes) is an inflammatory autoimmune disease associated with many complications including nephropathy, retinopathy, neuropathy and hyperalgesia. Experimental evidence has shown that the bradykinin B1 receptor (BKB1-R) is involved in the development of type 1 diabetes and found to be upregulated alongside the disease. In the present study the effects of the selective BKB1-R antagonist the R-954 (Ac-Orn-[Oic(2), alpha-MePhe(5), D-beta Nal(7), Ile(8) ]des-Arg(9)-BK and the BKB1-R agonist des Arg(9)-BK (DBK) were studied on diabetic hyperglycemia. Diabetic type 1 was induced in C57 BL/KsJ mdb male mice by five consecutives doses of STZ (45mg/kg i.p.). A glucose tolerance test (GTT) was performed by an intraperitoneal administration of glucose, 8, 12 and 18days after the diabetes induction. The induction of type 1 diabetes provoked a significant hyperglycemia levels in diabetic mice at 12 and 18days after STZ. The administration of R-954 (400microg/kg i.p.) at 12 and 18days after STZ returned the glycemia levels of this animals to normal values. In addition the administration of DKB (300microg/kg i.p.) significantly potentiated the diabetes-induced hyperglycemia; this effect that was totally reversed by R-954. These results provide further evidence for the implication of BKB1-R in the type 1 diabetes mellitus (insulitis).

  9. Modeling the effects of HER/ErbB1-3 co-expression on receptor dimerization and biological response

    SciTech Connect

    Shankaran, Harish; Wiley, H. S.; Resat, Haluk

    2006-06-01

    The human epidermal growth factor receptor (HER/ErbB) system comprises the epidermal growth factor receptor (EGFR/HER1) and three other homologues viz. HER2-4. This receptor system plays a critical role in cell proliferation and differentiation and receptor over-expression can be associated with poor prognosis in cancers of the epithelium. Here, we examine the effect of co-expressing varying levels of HER1-3 on the receptor dimerization patterns using a detailed kinetic model for ErbB heterodimerization and trafficking. Our results indicate that co-expression of EGFR with HER2 or HER3 biases signaling to the cell surface and retards signal down-regulation. In addition, simultaneous co-expression of HER1-3 leads to preferential formation of HER2-HER3 heterodimers, which are known to be potent inducers of cell growth and transformation. Analysis of the parameter dependencies in the model reveals that measurements of HER3 phosphorylation and HER2 internalization ratio may prove to be especially useful for the estimation of critical model parameters. Further, we examined the effect of receptor dimerization patterns on cell phenotype using a simple phenomenological model. Results indicate that co-expression of EGFR with HER2 and HER3 at low to moderate levels may enable cells to match the phenotype of a high HER2 expresser.

  10. Requirement of UNC93B1 reveals a critical role for Toll-Like Receptor 7 in host resistance to primary infection with Trypanosoma cruzi1,2

    PubMed Central

    Caetano, Braulia C.; Carmo, Bianca B.; Melo, Mariane B.; Cerny, Anna; dos Santos, Sara L.; Bartholomeu, Daniella C.; Golenbock, Douglas T.; Gazzinelli, Ricardo T.

    2011-01-01

    UNC93B1 associates with Toll-Like Receptor (TLR) 3, 7 and 9, mediating their translocation from the endoplasmic reticulum to the endolysosome, thus allowing proper activation by microbial nucleic acids. We found that the triple deficient ‘3d’ mice, which lack functional UNC93B1 as well as functional endossomal TLRs, are highly susceptible to infection with Trypanosoma cruzi. The enhanced parasitemia and mortality in 3d animals were associated with impaired pro-inflammatory response, including reduced levels of IL-12p40 and IFN-γ. Importantly, the phenotype of 3d mice was intermediary between MyD88−/− (highly susceptible) and TLR9−/− (less susceptible), indicating the involvement of an additional UN93B1-dependent-TLR(s) on host resistance to T. cruzi. Hence, our experiments also revealed that TLR7 is a critical innate immune receptor involved in recognition of parasite RNA, induction of IL-12p40 by dendritic cells, and consequent IFN-γ by T lymphocytes. Furthermore, we show that upon T. cruzi infection triple TLR3/7/9−/− mice had similar phenotype than 3d mice. These data imply that the nucleic acid-sensing TLRs are critical determinants of host resistance to primary infection with T. cruzi. PMID:21753151

  11. Bradykinin and angiotensin-converting enzyme inhibition in cardioprotection

    PubMed Central

    Jancso, G; Jaberansari, MT; Gasz, B; Szanto, Z; Cserepes, B; Röth, E

    2004-01-01

    OBJECTIVES: To show that angiotensin-converting enzyme (ACE) inhibition potentiates subthreshold ischemic preconditioning (IPC) via the elevation of bradykinin activity, leading to a fully delayed cardioprotective response. METHODS: On day 1 of the experiment, pigs were subjected to sham (group 1, controls) or IPC protocols. In groups 2 and 3, 4×5 min and 2×2 min of IPC, respectively, were elicited by occluding the left anterior descending coronary artery with percutaneous transluminal coronary angioplasty inflatable balloon catheter. Group 4 was subjected to the ACE inhibitor perindoprilate only. In group 5, the pigs were pretreated with perindoprilate (0.06 mg/kg) and then subjected to 2×2 min IPC. In group 6, intracoronary HOE 140 (a selective bradykinin B2 receptor antagonist) was added before the perindoprilateaugmented subthreshold (2×2 min) PC stimulus. On the second day, all animals underwent 40 min left anterior descending coronary artery ligation and 3 h reperfusion, followed by infarct size analysis using triphenyl tetrazolium chloride staining. RESULTS: The rates of infarct size and risk zone were the following in the experimental groups: group 1, 42.8%; group 2,19.5% (P<0.05); group 3, ischemia/reperfusion (I/R) 33.4%; group 4, I/R 18.4% (P<0.05); group 5, I/R 31.2%; and group 6, I/R 36.3%. A significant increase of nuclear factor kappa B activation in groups 2 and 4 was seen. CONCLUSIONS: Results confirm that ACE inhibitors do not give total pharmacological IPC, but they enhance the induction effect of small ischemic insults, which raises the ischemic tolerance of myocardium. It was determined that enhanced bradykinin activity leads to downstream nuclear factor kappa B activation in this model. PMID:19641692

  12. Carnosol, a Constituent of Zyflamend, Inhibits Aryl Hydrocarbon Receptor-Mediated Activation of CYP1A1 and CYP1B1 Transcription and Mutagenesis

    PubMed Central

    Mohebati, Arash; Guttenplan, Joseph B.; Kochhar, Amit; Zhao, Zhong-Lin; Kosinska, Wieslawa; Subbaramaiah, Kotha; Dannenberg, Andrew J.

    2012-01-01

    The aryl hydrocarbon receptor (AhR), a ligand-activated member of the basic-helix-loop-helix family of transcription factors, plays a significant role in polycyclic aromatic hydrocarbon (PAH) induced carcinogenesis. In the upper aerodigestive tract of humans, tobacco smoke, a source of PAHs, activates the AhR leading to increased expression of CYP1A1 and CYP1B1, which encode proteins that convert PAHs to genotoxic metabolites. Inhibitors of Hsp90 ATPase cause a rapid decrease in levels of AhR, an Hsp90 client protein, and thereby block PAH-mediated induction of CYP1A1 and CYP1B1. The main objective of this study was to determine whether Zyflamend, a polyherbal preparation, suppressed PAH-mediated induction of CYP1A1 and CYP1B1 and inhibited DNA adduct formation and mutagenesis. We also investigated whether carnosol, one of multiple phenolic antioxidants in Zyflamend, had similar inhibitory effects. Treatment of cell lines derived from oral leukoplakia (MSK-Leuk1) and skin (HaCaT) with benzo[a]pyrene (B[a]P), a prototypic PAH, induced CYP1A1 and CYP1B1 transcription, resulting in enhanced levels of message and protein. Both Zyflamend and carnosol suppressed these effects of B[a]P. Notably, both Zyflamend and carnosol inhibited Hsp90 ATPase activity and caused a rapid reduction in AhR levels. The formation of B[a]P induced DNA adducts and mutagenesis were also inhibited by Zyflamend and carnosol. Collectively, these results show that Zyflamend and carnosol inhibit Hsp90 ATPase leading to reduced levels of AhR, suppression of B[a]P-mediated induction of CYP1A1 and CYP1B1 and inhibition of mutagenesis. Carnosol-mediated inhibition of Hsp90 ATPase activity can help explain the chemopreventive activity of herbs such as Rosemary, which contain this phenolic antioxidant. PMID:22374940

  13. Canine external carotid vasoconstriction to methysergide, ergotamine and dihydroergotamine: role of 5-HT1B/1D receptors and α2-adrenoceptors

    PubMed Central

    Villalón, Carlos M; De Vries, Peter; Rabelo, Gonzalo; Centurión, David; Sánchez-López, Araceli; Saxena, Pramod

    1999-01-01

    The antimigraine drugs methysergide, ergotamine and dihydroergotamine (DHE) produce selective vasoconstriction in the external carotid bed of vagosympathectomized dogs anaesthetized with pentobarbital and artificially respired, but the receptors involved have not yet been completely characterized. Since the above drugs display affinity for several binding sites, including α-adrenoceptors and several 5-HT1 and 5-HT2 receptor subtypes, this study has analysed the mechanisms involved in the above responses. Intracarotid (i.c.) infusions during 1 min of methysergide (31–310 μg min−1), ergotamine (0.56–5.6 μg min−1) or DHE (5.6–31 μg min−1) dose-dependently reduced external carotid blood flow (ECBF) by up to 46±4, 37±4 and 49±5%, respectively. Blood pressure and heart rate remained unchanged. The reductions in ECBF by methysergide were abolished and even reversed to increases in animals pre-treated with GR127935 (10 μg kg−1, i.v.). The reductions in ECBF by ergotamine and DHE remained unchanged in animals pre-treated (i.v.) with prazosin (300 μg kg−1), but were partly antagonized in animals pre-treated with either GR127935 (10 or 30 μg kg−1) or yohimbine (1000 μg kg−1). Pre-treatment with a combination of GR127935 (30 μg kg−1) and yohimbine (1000 μg kg−1) abolished the responses to both ergotamine and DHE. The above doses of antagonists were shown to produce selective antagonism at their respective receptors. These results suggest that the external carotid vasoconstrictor responses to methysergide primarily involve 5-HT1B/1D receptors, whereas those to ergotamine and DHE are mediated by 5-HT1B/1D receptors as well as α2-adrenoceptors. PMID:10188968

  14. Plasma Kallikrein Promotes Epidermal Growth Factor Receptor Transactivation and Signaling in Vascular Smooth Muscle through Direct Activation of Protease-activated Receptors*

    PubMed Central

    Abdallah, Rany T.; Keum, Joo-Seob; Lee, Mi-Hye; Wang, Bing; Gooz, Monika; Luttrell, Deirdre K.; Luttrell, Louis M.; Jaffa, Ayad A.

    2010-01-01

    The kallikrein-kinin system, along with the interlocking renin-angiotensin system, is a key regulator of vascular contractility and injury response. The principal effectors of the kallikrein-kinin system are plasma and tissue kallikreins, proteases that cleave high molecular weight kininogen to produce bradykinin. Most of the cellular actions of kallikrein (KK) are thought to be mediated by bradykinin, which acts via G protein-coupled B1 and B2 bradykinin receptors on VSMCs and endothelial cells. Here, we find that primary aortic vascular smooth muscle but not endothelial cells possess the ability to activate plasma prekallikrein. Surprisingly, exposing VSMCs to prekallikrein leads to activation of the ERK1/2 mitogen-activated protein kinase cascade via a mechanism that requires kallikrein activity but does not involve bradykinin receptors. In transfected HEK293 cells, we find that plasma kallikrein directly activates G protein-coupled protease-activated receptors (PARs) 1 and 2, which possess consensus kallikrein cleavage sites, but not PAR4. In vascular smooth muscles, KK stimulates ADAM (a disintegrin and metalloprotease) 17 activity via a PAR1/2 receptor-dependent mechanism, leading sequentially to release of the endogenous ADAM17 substrates, amphiregulin and tumor necrosis factor-α, metalloprotease-dependent transactivation of epidermal growth factor receptors, and metalloprotease and epidermal growth factor receptor-dependent ERK1/2 activation. These results suggest a novel mechanism of bradykinin-independent kallikrein action that may contribute to the regulation of vascular responses in pathophysiologic states, such as diabetes mellitus. PMID:20826789

  15. Bradykinin-potentiating peptides: beyond captopril.

    PubMed

    Camargo, Antonio C M; Ianzer, Danielle; Guerreiro, Juliano R; Serrano, Solange M T

    2012-03-15

    The identification of novel endogenous and exogenous molecules acting in the complex mechanism of regulating the vascular tonus has always been of great interest. The discovery of bradykinin (1949) and the bradykinin-potentiating peptides (1965) had a pivotal influence in the field, respectively, in understanding cardiovascular pathophysiology and in the development of captopril, the first active-site directed inhibitor of angiotensin-converting enzyme, and used worldwide to treat human hypertension. Both discoveries originated from studies of envenoming by the snake Bothrops jararaca. The aim of the present article is to reveal that the snake proline-rich oligopeptides, known as bradykinin-potentiating peptides, are still a source of surprising scientific discoveries, some of them useful not only to reveal potential new targets but also to introduce prospective lead molecules for drug development. In particular, we emphasize argininosuccinate synthetase as a new functional target for one of bradykinin-potentiating peptides found in B. jararaca, Bj-BPP-10c. This decapeptide leads to argininosuccinate synthetase activation, consequently sustaining increased nitric oxide production, a critical endogenous molecule to reduce the arterial blood pressure.

  16. Dopamine D2-Receptor Antagonists Down-Regulate CYP1A1/2 and CYP1B1 in the Rat Liver

    PubMed Central

    Harkitis, P.; Lang, M. A.; Marselos, M.; Fotopoulos, A.; Albucharali, G.; Konstandi, M.

    2015-01-01

    Dopaminergic systems regulate the release of several hormones including growth hormone (GH), thyroid hormones, insulin, glucocorticoids and prolactin (PRL) that play significant roles in the regulation of various Cytochrome P450 (CYP) enzymes. The present study investigated the role of dopamine D2-receptor-linked pathways in the regulation of CYP1A1, CYP1A2 and CYP1B1 that belong to a battery of genes controlled by the Aryl Hydrocarbon Receptor (AhR) and play a crucial role in the metabolism and toxicity of numerous environmental toxicants. Inhibition of dopamine D2-receptors with sulpiride (SULP) significantly repressed the constitutive and benzo[a]pyrene (B[a]P)-induced CYP1A1, CYP1A2 and CYP1B expression in the rat liver. The expression of AhR, heat shock protein 90 (HSP90) and AhR nuclear translocator (ARNT) was suppressed by SULP in B[a]P-treated livers, whereas the AhRR expression was increased by the drug suggesting that the SULP-mediated repression of the CYP1 inducibility is due to inactivation of the AhR regulatory system. At signal transduction level, the D2-mediated down-regulation of constitutive CYP1A1/2 and CYP1B1 expression appears to be mediated by activation of the insulin/PI3K/AKT pathway. PRL-linked pathways exerting a negative control on various CYPs, and inactivation of the glucocorticoid-linked pathways that positively control the AhR-regulated CYP1 genes, may also participate in the SULP-mediated repression of both, the constitutive and induced CYP1 expression. The present findings indicate that drugs acting as D2-dopamine receptor antagonists can modify several hormone systems that regulate the expression of CYP1A1, CYP1A2 and CYP1B1, and may affect the toxicity and carcinogenicity outcome of numerous toxicants and pre-carcinogenic substances. Therefore, these drugs could be considered as a part of the strategy to reduce the risk of exposure to environmental pollutants and pre-carcinogens. PMID:26466350

  17. Involvement of bradykinin, cytokines, sympathetic amines and prostaglandins in formalin-induced orofacial nociception in rats

    PubMed Central

    Chichorro, Juliana G; Lorenzetti, Berenice B; Zampronio, Aleksander R

    2004-01-01

    This study characterises some of the mechanisms and mediators involved in the orofacial nociception triggered by injection of formalin into the upper lip of the rat, by assessing the influence of various treatments on behavioural nociceptive responses (duration of facial rubbing) elicited either by a low subthreshold (i.e. non-nociceptive; 0.63%) or a higher concentration of the algogen (2.5%). The kininase II inhibitor captopril (5 mg kg−1, s.c.) and prostaglandin(PG) E2 (100 ng lip−1) potentiated both phases of the response to 0.63% formalin, whereas tumour necrosis factor (TNFα; 5 pg lip−1), interleukin(IL)-1β (0.5 pg lip−1), IL-6 (2 ng lip−1) and IL-8 (200 pg lip−1), or the indirectly acting sympathomimetic drug tyramine (200 μg lip−1), each augmented only the second phase of nociception. Conversely, both phases of nociception induced by 2.5% formalin were inhibited by the bradykinin (BK) B2 receptor antagonist HOE140 (5 μg lip−1) or the selective β1-adrenoceptor antagonist atenolol (100 μg lip−1). However, the BK B1 receptor antagonist des-Arg9-Leu8-BK (1 and 2 μg lip−1), antibody and/or antiserum against each of the cytokines, the adrenergic neurone blocker guanethidine (30 mg kg−1 day−1, s.c., for 3 days) and the cyclooxygenase(COX)-2 inhibitor celecoxib (50 and 200 μg lip−1, s.c.; or 1 and 3 mg kg−1, i.p.) reduced only the second phase of the response. The nonselective COX inhibitor indomethacin and the 5-lipoxygenase activating protein inhibitor MK886 did not change formalin-induced nociception. Our results indicate that BK, TNF-α, IL-1β, IL-6, IL-8, sympathetic amines and PGs (but not leukotrienes) contribute significantly to formalin-induced orofacial nociception in the rat and the response seems to be more susceptible to inhibition by B2 receptor antagonist and selective COX-2 inhibitor than by B1 receptor antagonist or nonselective COX inhibitor. PMID:15006904

  18. Evidence for 5-HT1B/1D and 5-HT2A receptors mediating constriction of the canine internal carotid circulation

    PubMed Central

    Centurión, David; Ortiz, Mario I; Sánchez-López, Araceli; De Vries, Peter; Saxena, Pramod R; Villalón, Carlos M

    2001-01-01

    The present study has investigated the preliminary pharmacological profile of the receptors mediating vasoconstriction to 5-hydroxytryptamine (5-HT) in the internal carotid bed of vagosympathectomised dogs. One minute intracarotid infusions of the agonists 5-HT (0.1–10 μg min−1), sumatriptan (0.3–10 μg min−1; 5-HT1B/1D), 5-methoxytryptamine (1–100 μg min−1; 5-HT1, 5-HT2, 5-HT4, 5-ht6 and 5-HT7) or DOI (0.31–10 μg min−1; 5-HT2), but not 5-carboxamidotryptamine (0.01–0.3 μg min−1; 5-HT1, 5-ht5A and 5-HT7), 1-(m-chlorophenyl)-biguanide (mCPBG; 1–1000 μg min−1; 5-HT3) or cisapride (1–1000 μg min−1; 5-HT4), resulted in dose-dependent decreases in internal carotid blood flow, without changing blood pressure or heart rate. The vasoconstrictor responses to 5-HT, which remained unaffected after saline, were resistant to blockade by i.v. administration of the antagonists ritanserin (100 μg kg−1; 5-HT2A/2B/2C) in combination with tropisetron (3000 μg kg−1; 5-HT3/4) or the cyclo-oxygenase inhibitor, indomethacin (5000 μg kg−1), but were abolished by the 5-HT1B/1D receptor antagonist, GR127935 (30 μg kg−1). Interestingly, after administration of GR127935, the subsequent administration of ritanserin unmasked a dose-dependent vasodilator component. GR127935 or saline did not practically modify the vasoconstrictor effects of 5-MeO-T. In animals receiving GR127935, the subsequent administration of ritanserin abolished the vasoconstrictor responses to 5-MeO-T unmasking a dose-dependent vasodilator component. The vasoconstriction induced by sumatriptan was antagonized by GR127935, but not by ritanserin. Furthermore, ritanserin (100 μg kg−1) or ketanserin (100 μg kg−1; 5-HT2A), but not GR127935, abolished DOI-induced vasoconstrictor responses. The above results suggest that 5-HT-induced internal carotid vasoconstriction is predominantly mediated by 5-HT1B/1D and 5-HT2A receptors

  19. Hepatic lipase promotes the selective uptake of high density lipoprotein-cholesteryl esters via the scavenger receptor B1.

    PubMed

    Lambert, G; Chase, M B; Dugi, K; Bensadoun, A; Brewer, H B; Santamarina-Fojo, S

    1999-07-01

    Hepatic lipase (HL) plays a major role in high-density lipoprotein (HDL) metabolism both as a lipolytic enzyme and as a ligand. To investigate whether HL enhances the uptake of HDL-cholesteryl ester (CE) via the newly described scavenger receptor BI (SR-BI), we measured the effects of expressing HL and SR-BI on HDL-cell association as well as uptake of 125I-labeled apoA-I and [3H]CE-HDL, by embryonal kidney 293 cells. As expected, HDL cell association and CE selective uptake were increased in SR-BI transfected cells by 2- and 4-fold, respectively, compared to controls (P < 0.001). Cells transfected with HL alone or in combination with SR-BI expressed similar amounts of HL, 20% of which was bound to cell surface proteoglycans. HL alone increased HDL cell association by 2-fold but had no effect on HDL-CE uptake in 293 cells. However, in cells expressing SR-BI, HL further enhanced the selective uptake of CE from HDL by 3-fold (P < 0.001). To determine whether the lipolytic and/or ligand function of HL are required in this process, we generated a catalytically inactive form of HL (HL-145G). Cells co-transfected with HL-145G and SR-BI increased their HDL cell association and HDL-CE selective uptake by 1.4-fold compared to cells expressing SR-BI only (P < 0.03). Heparin abolished the effect of HL-145G on SR-BI-mediated HDL-CE selective uptake.Thus, the enhanced uptake of HDL-CE by HL is mediated by both its ligand role, which requires interaction with proteoglycans, and by lipolysis with subsequent HDL particle remodeling. These results establish HL as a major modulator of SR-BI mediated selective uptake of HDL-CE.

  20. Extra-epitopic hepatitis C virus polymorphisms confer resistance to broadly neutralizing antibodies by modulating binding to scavenger receptor B1

    PubMed Central

    El-Diwany, Ramy; Mankowski, Madeleine C.; Wasilewski, Lisa N.; Brady, Jillian K.; Snider, Anna E.; Osburn, William O.; Murrell, Ben; Ray, Stuart C.

    2017-01-01

    Broadly-neutralizing monoclonal antibodies (bNAbs) may guide vaccine development for highly variable viruses including hepatitis C virus (HCV), since they target conserved viral epitopes that could serve as vaccine antigens. However, HCV resistance to bNAbs could reduce the efficacy of a vaccine. HC33.4 and AR4A are two of the most potent anti-HCV human bNAbs characterized to date, binding to highly conserved epitopes near the amino- and carboxy-terminus of HCV envelope (E2) protein, respectively. Given their distinct epitopes, it was surprising that these bNAbs showed similar neutralization profiles across a panel of natural HCV isolates, suggesting that some viral polymorphisms may confer resistance to both bNAbs. To investigate this resistance, we developed a large, diverse panel of natural HCV envelope variants and a novel computational method to identify bNAb resistance polymorphisms in envelope proteins (E1 and E2). By measuring neutralization of a panel of HCV pseudoparticles by 10 μg/mL of each bNAb, we identified E1E2 variants with resistance to one or both bNAbs, despite 100% conservation of the AR4A binding epitope across the panel. We discovered polymorphisms outside of either binding epitope that modulate resistance to both bNAbs by altering E2 binding to the HCV co-receptor, scavenger receptor B1 (SR-B1). This study is focused on a mode of neutralization escape not addressed by conventional analysis of epitope conservation, highlighting the contribution of extra-epitopic polymorphisms to bNAb resistance and presenting a novel mechanism by which HCV might persist even in the face of an antibody response targeting multiple conserved epitopes. PMID:28235087

  1. Bradykinin enhances invasion of malignant glioma into the brain parenchyma by inducing cells to undergo amoeboid migration

    PubMed Central

    Seifert, Stefanie; Sontheimer, Harald

    2014-01-01

    Abstract The molecular and cellular mechanisms governing cell motility and directed migration in response to the neuropeptide bradykinin are largely unknown. Here, we demonstrate that human glioma cells whose migration is guided by bradykinin generate bleb-like protrusions. We found that activation of the B2 receptor leads to a rise in free Ca2+ from internal stores that activates actomyosin contraction and subsequent cytoplasmic flow into protrusions forming membrane blebs. Furthermore Ca2+ activates Ca2+-dependent K+ and Cl− channels, which participate in bleb regulation. Treatment of gliomas with bradykinin in situ increased glioma growth by increasing the speed of cell migration at the periphery of the tumour mass. To test if bleb formation is related to bradykinin-promoted glioma invasion we blocked glioma migration with blebbistatin, a blocker of myosin kinase II, which is necessary for proper bleb retraction. Our findings suggest a pivotal role of bradykinin during glioma invasion by stimulating amoeboid migration of glioma cells. PMID:25194042

  2. Endothelium-dependent relaxation and hyperpolarization evoked by bradykinin in canine coronary arteries: enhancement by exercise-training.

    PubMed Central

    Mombouli, J. V.; Nakashima, M.; Hamra, M.; Vanhoutte, P. M.

    1996-01-01

    bradykinin were also shifted to the left by perindoprilat. The shift induced by the ACE-inhibitor in either type of preparation was not significantly different. 8. These findings demonstrate that exercise-training augments the sensitivity of the coronary artery of the dog to the endothelium-dependent effects of bradykinin. This sensitization to bradykinin may reflect an increased role of both NO and EDHF, and is not the consequence of differences in ACE activity in the receptor compartment. PMID:8821528

  3. MRP transporters as membrane machinery in the bradykinin-inducible export of ATP.

    PubMed

    Zhao, Yumei; Migita, Keisuke; Sun, Jing; Katsuragi, Takeshi

    2010-04-01

    Adenosine triphosphate (ATP) plays the role of an autocrine/paracrine signal molecule in a variety of cells. So far, however, the membrane machinery in the export of intracellular ATP remains poorly understood. Activation of B2-receptor with bradykinin-induced massive release of ATP from cultured taenia coli smooth muscle cells. The evoked release of ATP was unaffected by gap junction hemichannel blockers, such as 18alpha-glycyrrhetinic acid and Gap 26. Furthermore, the cystic fibrosis transmembrane regulator (CFTR) coupled Cl(-) channel blockers, CFTR(inh)172, 5-nitro-2-(3-phenylpropylamino)-benzoic acid, Gd3(+) and glibenclamide, failed to suppress the export of ATP by bradykinin. On the other, the evoked release of ATP was greatly reduced by multidrug resistance protein (MRP) transporter inhibitors, MK-571, indomethacin, and benzbromarone. From western blotting analysis, blots of MRP 1 protein only, but not MRP 2 and MRP 3 protein, appeared at 190 kD. However, the MRP 1 protein expression was not enhanced after loading with 1 muM bradykinin for 5 min. Likewise, niflumic acid and fulfenamic acid, Ca2(+)-activated Cl(-) channel blockers, largely abated the evoked release of ATP. The possibility that the MRP transporter system couples with Ca2(+)-activated Cl(-) channel activities is discussed here. These findings suggest that MRP transporters, probably MRP 1, unlike CFTR-Cl(-) channels and gap junction hemichannels, may contribute as membrane machinery to the export of ATP induced by G-protein-coupled receptor stimulation.

  4. A comparative study of kinin, kallidin, and bradykinin

    PubMed Central

    Holdstock, D. J.; Mathias, A. P.; Schachter, M.

    1957-01-01

    Partially purified kinin, a polypeptide in wasp venom, has been found to be a potent smooth-muscle stimulating and hypotensive agent. Such a preparation was 10 to 100 times more effective than histamine in enhancing capillary permeability on intradermal injection, and 10 times more effective than acetylcholine in evoking pain on a cutaneous blister base. Some differences between the actions of salivary kallikrein and trypsin in releasing kallidin or bradykinin have been observed, and some modifications of previous methods of preparing crude kallidin and bradykinin are suggested. Kallidin and bradykinin are effective enhancers of capillary permeability in the guinea-pig and rabbit. Chemical and pharmacological tests failed to differentiate between kallidin and bradykinin which must be, therefore, closely similar compounds. The possible role of kallidin and bradykinin in physiological or pathological conditions is discussed. ImagesFIG. 3FIG. 4FIG. 7 PMID:13446366

  5. SH2B1beta (SH2-Bbeta) enhances expression of a subset of nerve growth factor-regulated genes important for neuronal differentiation including genes encoding urokinase plasminogen activator receptor and matrix metalloproteinase 3/10.

    PubMed

    Chen, Linyi; Maures, Travis J; Jin, Hui; Huo, Jeffrey S; Rabbani, Shafaat A; Schwartz, Jessica; Carter-Su, Christin

    2008-02-01

    Previous work showed that the adapter protein SH2B adapter protein 1beta (SH2B1) (SH2-B) binds to the activated form of the nerve growth factor (NGF) receptor TrkA and is critical for both NGF-dependent neurite outgrowth and maintenance. To identify SH2B1beta-regulated genes critical for neurite outgrowth, we performed microarray analysis of control PC12 cells and PC12 cells stably overexpressing SH2B1beta (PC12-SH2B1beta) or the dominant-negative SH2B1beta(R555E) [PC12-SH2B1beta(R555E)]. NGF-induced microarray expression of Plaur and Mmp10 genes was greatly enhanced in PC12-SH2B1beta cells, whereas NGF-induced Plaur and Mmp3 expression was substantially depressed in PC12-SH2B1beta(R555E) cells. Plaur, Mmp3, and Mmp10 are among the 12 genes most highly up-regulated after 6 h of NGF. Their protein products [urokinase plasminogen activator receptor (uPAR), matrix metalloproteinase 3 (MMP3), and MMP10] lie in the same pathway of extracellular matrix degradation; uPAR has been shown previously to be critical for NGF-induced neurite outgrowth. Quantitative real-time PCR analysis revealed SH2B1beta enhancement of NGF induction of all three genes and the suppression of NGF induction of all three when endogenous SH2B1 was reduced using short hairpin RNA against SH2B1 and in PC12-SH2B1beta(R555E) cells. NGF-induced levels of uPAR and MMP3/10 and neurite outgrowth through Matrigel (MMP3-dependent) were also increased in PC12-SH2B1beta cells. These results suggest that SH2B1beta stimulates NGF-induced neuronal differentiation at least in part by enhancing expression of a specific subset of NGF-sensitive genes, including Plaur, Mmp3, and/or Mmp10, required for neurite outgrowth.

  6. Skatole (3-Methylindole) Is a Partial Aryl Hydrocarbon Receptor Agonist and Induces CYP1A1/2 and CYP1B1 Expression in Primary Human Hepatocytes

    PubMed Central

    Balaguer, Patrick; Ekstrand, Bo; Daujat-Chavanieu, Martine; Gerbal-Chaloin, Sabine

    2016-01-01

    Skatole (3-methylindole) is a product of bacterial fermentation of tryptophan in the intestine. A significant amount of skatole can also be inhaled during cigarette smoking. Skatole is a pulmonary toxin that induces the expression of aryl hydrocarbon receptor (AhR) regulated genes, such as cytochrome P450 1A1 (CYP1A1), in human bronchial cells. The liver has a high metabolic capacity for skatole and is the first organ encountered by the absorbed skatole; however, the effect of skatole in the liver is unknown. Therefore, we investigated the impact of skatole on hepatic AhR activity and AhR-regulated gene expression. Using reporter gene assays, we showed that skatole activates AhR and that this is accompanied by an increase of CYP1A1, CYP1A2 and CYP1B1 expression in HepG2-C3 and primary human hepatocytes. Specific AhR antagonists and siRNA-mediated AhR silencing demonstrated that skatole-induced CYP1A1 expression is dependent on AhR activation. The effect of skatole was reduced by blocking intrinsic cytochrome P450 activity and indole-3-carbinole, a known skatole metabolite, was a more potent inducer than skatole. Finally, skatole could reduce TCDD-induced CYP1A1 expression, suggesting that skatole is a partial AhR agonist. In conclusion, our findings suggest that skatole and its metabolites affect liver homeostasis by modulating the AhR pathway. PMID:27138278

  7. Combined inhibition of ErbB1/2 and Notch receptors effectively targets breast ductal carcinoma in situ (DCIS) stem/progenitor cell activity regardless of ErbB2 status.

    PubMed

    Farnie, Gillian; Willan, Pamela M; Clarke, Robert B; Bundred, Nigel J

    2013-01-01

    Pathways involved in DCIS stem and progenitor signalling are poorly understood yet are critical to understand DCIS biology and to develop new therapies. Notch and ErbB1/2 receptor signalling cross talk has been demonstrated in invasive breast cancer, but their role in DCIS stem and progenitor cells has not been investigated. We have utilised 2 DCIS cell lines, MCF10DCIS.com (ErbB2-normal) and SUM225 (ErbB2-overexpressing) and 7 human primary DCIS samples were cultured in 3D matrigel and as mammospheres in the presence, absence or combination of the Notch inhibitor, DAPT, and ErbB1/2 inhibitors, lapatinib or gefitinib. Western blotting was applied to assess downstream signalling. In this study we demonstrate that DAPT reduced acini size and mammosphere formation in MCF10DCIS.com whereas there was no effect in SUM225. Lapatinb reduced acini size and mammosphere formation in SUM225, whereas mammosphere formation and Notch1 activity were increased in MCF10DCIS.com. Combined DAPT/lapatinib treatment was more effective at reducing acini size in both DCIS cell lines. Mammosphere formation in cell lines and human primary DCIS was reduced further by DAPT/lapatinib or DAPT/gefitinib regardless of ErbB2 receptor status. Our pre-clinical human models of DCIS demonstrate that Notch and ErbB1/2 both play a role in DCIS acini growth and stem cell activity. We report for the first time that cross talk between the two pathways in DCIS occurs regardless of ErbB2 receptor status and inhibition of Notch and ErbB1/2 was more efficacious than either alone. These data provide further understanding of DCIS biology and suggest treatment strategies combining Notch and ErbB1/2 inhibitors should be investigated regardless of ErbB2 receptor status.

  8. Cardiovascular actions of rattlesnake bradykinin ([Val1,Thr6]bradykinin) in the anesthetized South American rattlesnake Crotalus durissus terrificus.

    PubMed

    Galli, Gina L J; Skovgaard, Nini; Abe, Augusto S; Taylor, Edwin W; Conlon, J Michael; Wang, Tobias

    2005-02-01

    Incubation of heat-denatured plasma from the rattlesnake Crotalus atrox with trypsin generated a bradykinin (BK) that contained two amino acid substitutions (Arg1 --> Val and Ser6 --> Thr) compared with mammalian BK. Bolus intra-arterial injections of synthetic rattlesnake BK (0.01-10 nmol/kg) into the anesthetized rattlesnake, Crotalus durissus terrificus, produced a pronounced and concentration-dependent increase in systemic vascular conductance (Gsys). This caused a fall in systemic arterial blood pressure (Psys) and an increase in blood flow. Heart rate and stroke volume also increased. This primary response was followed by a significant rise in Psys and pronounced tachycardia (secondary response). Pretreatment with N(G)-nitro-L-arginine methyl ester reduced the NK-induced systemic vasodilatation, indicating that the effect is mediated through increased NO synthesis. The tachycardia associated with the late primary and secondary response to BK was abolished with propranolol and the systemic vasodilatation produced in the primary phase was also significantly attenuated by pretreatment, indicating that the responses are caused, at least in part, by release of cathecholamines and subsequent stimulation of beta-adrenergic receptors. In contrast, the pulmonary circulation was relatively unresponsive to BK.

  9. Phospholipase C and protein kinase A mediate bradykinin sensitization of TRPA1: a molecular mechanism of inflammatory pain.

    PubMed

    Wang, Shenglan; Dai, Yi; Fukuoka, Tetsuo; Yamanaka, Hiroki; Kobayashi, Kimiko; Obata, Koichi; Cui, Xiuyu; Tominaga, Makoto; Noguchi, Koichi

    2008-05-01

    Bradykinin is an inflammatory mediator that plays a pivotal role in pain and hyperalgesia in inflamed tissues by exciting and/or sensitizing nociceptors. TRPA1 is an important component of the transduction machinery through which environmental irritants and endogenous proalgesic agents depolarize nociceptors to elicit inflammatory pain. Here, using electrophysiological, immunocytochemical and behavioural analyses, we showed a functional interaction of these two inflammation-related molecules in both heterologous expressing systems and primary sensory neurons. We found that bradykinin increased the TRPA1 currents evoked by allyl isothiocyanate (AITC) or cinnamaldehyde in HEK293 cells expressing TRPA1 and bradykinin receptor 2 (B2R). This potentiation was inhibited by phospholipase C (PLC) inhibitor or protein kinase A (PKA) inhibitor, and mimicked by PLC or PKA activator. The functional interaction between B2R and TRPA1, as well as the modulation mechanism, was also observed in rat dorsal root ganglia neurons. In an occlusion experiment, the PLC activator could enhance AITC-induced TRPA1 current further even in saturated PKA-mediated potentiation, indicating the additive potentiating effects of the PLC and PKA pathways. These data for the first time indicate that a cAMP-PKA signalling is involved in the downstream from B2R in dorsal root ganglia neurons in addition to PLC. Finally, subcutaneous pre-injection of a sub-inflammatory dose of bradykinin into rat hind paw enhanced AITC-induced pain behaviours, which was consistent with the observations in vitro. Collectively, these results represent a novel mechanism through which bradykinin released in response to tissue inflammation might trigger the sensation of pain by TRPA1 activation.

  10. The effect of the juvenile hormone analog, fenoxycarb, on ecdysone receptor B1 expression in the midgut of Bombyx mori during larval-pupal metamorphosis.

    PubMed

    Goncu, Ebru; Parlak, Osman

    2012-04-24

    The Bombyx mori (Lepidoptera: Bombycidae) midgut undergoes remodeling during the larval-pupal metamorphosis. All metamorphic events in insects are controlled by mainly two hormones: 20-hydroxyecdysone (20E) and juvenile hormone (JH). Fenoxycarb, O-ethyl N-(2-(4-phenoxyphenoxy)-ethyl) carbamate, has been shown to be one of the most potent juvenile hormone analogs against a variety of insect species. In this study, the effect of fenoxycarb on EcR-B1 protein expression in the midgut of Bombyx mori during the remodeling processwas investigated. Fenoxycarb was topically treated to the beginning of the fifth instar Bombyx larvae. Its application prolonged the last instar and prevented metamorphic events. Analyses were performed from day 6 of the fifth instar to 24 hr after pupation in controls and to day 14 of the fifth instar in the fenoxycarb treated group. According to our results, the presence of EcR-B1 in the midguts of the fenoxycarb treated group during the feeding period suggested that EcR-B1 was involved in the functioning of larval cells and during this period fenoxycarb did not affect EcR-B1 status. Immediately after termination of the feeding stage, the amount of EcR-B1 protein increased, which indicated that it may strengthen the ecdysone signal for commitment of remodeling process. In the fenoxycarb treated group, its upregulation was delayed, which may be related to the inhibition of ecdysone secretion from the prothoracic gland.

  11. Bradykinin may be involved in neuropeptide Y-induced diuresis, natriuresis, and calciuresis.

    PubMed

    Bischoff, A; Rascher, W; Michel, M C

    1998-10-01

    Neuropeptide Y (NPY) can cause diuresis, natriuresis, and calciuresis in rats independently of the pressure-natriuresis mechanism (A. Bischoff and M. C. Michel. Pflügers Arch. 435: 443-453, 1998). Because this is seen in systemic but not intrarenal NPY infusion, we have investigated the possible mediator of tubular NPY effects in anesthetized rats. In the present study, infusion of NPY (2 micrograms . kg-1 . min-1) enhanced renovascular resistance by approximately 8 mmHg . ml-1 . min and enhanced urine and sodium excretion by approximately 450 microliter/15 min and approximately 60-85 micromol/15 min, respectively. Acute renal denervation did not alter renovascular or tubular NPY effects, indicating that a neuronally released mediator is not involved. Treatment with the angiotensin II-receptor antagonist losartan prevented the decline of the renovascular response with time but did not modify tubular NPY effects. The bradykinin B2-receptor antagonist icatibant accelerated the decline of the renovascular NPY effects with time; concomitantly, it attenuated NPY-induced diuresis and natriuresis and abolished NPY-induced calciuresis. The converting-enzyme inhibitor ramiprilat prevented the decline of the renovascular response with time; concomitantly, it magnified the NPY-induced diuresis, natriuresis, and calciuresis. We conclude that bradykinin may be involved in NPY-induced diuresis, natriuresis, and, in particular, calciuresis.

  12. Diabetes modulates the expression of glomerular kinin receptors.

    PubMed

    Christopher, Julie; Jaffa, Ayad A

    2002-12-01

    The localization of kinin receptors within the kidney implicates this system in the regulation of glomerular hemodynamics. We reported that diabetes alters the activity of the renal kallikrein-kinin system, and that these alterations contribute to the development of microvascular complications of diabetes. The present study examined the influence of diabetes on the expression of glomerular B1 and B2-kinin receptors, and assessed the cellular signaling of kinin receptor activation. Rats made diabetic with streptozocin (85 mg/kg), displayed plasma glucose levels in the range of 350-500 mg/dl. At 3, 7, and 21 days, B1 and B2-kinin receptor mRNA levels were measured in isolated glomeruli from control and diabetic rats by RT-PCR. Glomeruli revealed a differential pattern of expression between the two kinin receptors. The constitutively expressed B2-receptor was increased three-fold at day 3, but returned to normal levels at day 7; whereas, the inducible B1-receptor was maximally expressed (20-fold) at day 7 and remained elevated (10-fold) at day 21. To test whether the induction of kinin receptors by diabetes translates into increased responsiveness, we measured mitogen-activated protein kinase (MAPK) phosphorylation (p42, p44) in glomeruli isolated from control and diabetic rats stimulated with B1-receptor agonist (des-Arg9-bradykinin, 10(-8) M). A three-fold increase in phosphorylation of MAPK was observed in response to B1-receptor agonist challenge in glomeruli isolated form diabetic rats compared to controls. These findings demonstrate for the first time that glomerular kinin receptors are induced by diabetes, and provide a rationale to study the contribution of these receptors to the development of glomerular injury in diabetes.

  13. Effects of chlorobutanol and bradykinin on myocardial excitation.

    PubMed

    Hermsmeyer, K; Aprigliano, O

    1976-02-01

    The negative inotropic effect of a commonly used formulation of bradykinin (Sandoz BRS-640) was found to be due to chlorobutanol, a constituent of the preparation. Solutions containing up to 100 mug of crystalline bradykinin/ml had no effect on tension or action-potential shape. Chlorobutanol (500 mug/ml) caused a 30% decrease in contraction amplitude and a 20% increase in action-potential duration. Chlorobutanol lowered conduction velocity and induced conduction failure and automaticity within isolated ventricular muscle strips. Chlorobutanol affected neither positive nor negative treppe. We conclude that bradykinin has no direct action on toad, frog, or rat myocardium. However, chlorobutanol does have direct effects on myocardial cells, acting on the cell membrane and decreasing isometric tension produced by the heart.

  14. Interactions of histamine and bradykinin on polymodal C-fibres in isolated rat skin.

    PubMed

    Koppert, W; Martus, P; Reeh, P W

    2001-01-01

    Patients suffering from pruritus due to atopic dermatitis show, in asymptomatic skin, reduced itch and flare responses to histamine, the major pruritogenic mediator. We hypothesized that this apparent loss in histamine sensitivity may be overcompensated in inflamed skin and investigated the interactions between histamine and bradykinin, the major inflammatory mediator. The studies were performed using the isolated rat skin-nerve preparation. Forty-two fibres were tested following four different experimental protocols. After characterization of the sensory properties, six fibres were treated repetitively with histamine (HIS1, HIS2) to exclude the possibility that the responses (spikes/min) increase simply by repetition. In 12 other units, histamine (HIS1) was followed by a wash-out period prior to bradykinin (BK) stimulation; in another 12 units, BK followed immediately after HIS1. A further 12 fibres were examined without preceding heat stimulation in order to avoid possible sensitization. If BK was administered after a wash-out period following HIS1, the BK responses were significantly higher than the HIS1 response. The BK response showed a peak discharge which was absent if BK followed directly upon HIS1. If HIS2 was applied directly following BK, the induced discharge was significantly larger than the first histamine response and not different from the BK response, whereas a washout period before HIS2 abolished the sensitizing effect of previous BK.A unidirectional sensitization by previous bradykinin or heat stimulation on the histamine responsiveness of polymodal nociceptors has been demonstrated. If 'itch fibres' in humans were subject to similar interactions of histamine with inflammatory mediators, this may compensate for a down-regulation of histamine receptors in eczematic skin and possibly account for the pruritus.

  15. Avermectin B1

    Integrated Risk Information System (IRIS)

    Avermectin B1 ; CASRN 65195 - 55 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic E

  16. Triclosan activates aryl hydrocarbon receptor (AhR)-dependent apoptosis and affects Cyp1a1 and Cyp1b1 expression in mouse neocortical neurons.

    PubMed

    Szychowski, Konrad A; Wnuk, Agnieszka; Kajta, Małgorzata; Wójtowicz, Anna K

    2016-11-01

    Triclosan (TCS) is an antimicrobial agent that is used extensively in personal care and in sanitizing products, such as soaps, toothpastes, and hair products. A number of studies have revealed the presence of TCS in human tissues, such as fat, liver and brain, in addition to blood and breast milk. The aim of the present study was to investigate the impact of TCS on AhR and Cyp1a1/Cyp1b1 signaling in mouse neocortical neurons in primary cultures. In addition to the use of selective ligands and siRNAs, expression levels of mRNA and proteins as well as caspase-3 activity, reactive oxygen species (ROS) formation, and lactate dehydrogenase (LDH) release have been measured. We also studied the involvement of the AhR in TCS-induced LDH release and caspase-3 activation as well as the effect of TCS on ROS generation. Cultures of neocortical neurons were prepared from Swiss mouse embryos on day 15/16 of gestation. The cells were cultured in phenol red-free Neurobasal medium with B27 and glutamine, and the neurons were exposed to 1 and 10µM TCS. Our experiments showed that the expression of AhR and Cyp1a1 mRNA decreased in cells exposed to 10µM TCS for 3 or 6h. In the case of Cyp1b1, mRNA expression remained unchanged compared with the control group following 3h of exposure to TCS, but after 6h, the mRNA expression of Cyp1b1 was decreased. Our results confirmed that the AhR is involved in the TCS mechanism of action, and our data demonstrated that after the cells were transfected with AhR siRNA, the cytotoxic and pro-apoptotic properties of TCS were decreased. The decrease in Cyp1a1 mRNA and protein expression levels accompanied by a decrease in its activity. The stimulation of Cyp1a1 activity produced by the application of an AhR agonist (βNF) was attenuated by TCS, whereas the addition of AhR antagonist (αNF) reversed the inhibitory effects of TCS. In our experiments, TCS diminished Cyp1b1 mRNA and enhanced its protein expression. In case of Cyp1a1 we observed

  17. Determination of bradykinin and arg-bradykinin in rat muscle tissue by microdialysis and capillary column-switching liquid chromatography with mass spectrometric detection.

    PubMed

    Wilson, Steven Ray; Boix, Fernando; Holm, Anders; Molander, Pål; Lundanes, Elsa; Greibrokk, Tyge

    2005-09-01

    Quantification of bradykinin peptides in limited amounts of rat muscle tissue dialysate has been performed using a packed capillary LC-ESI-TOF-MS method. The micro dialysate samples (450 microL) with added internal standard were loaded onto a 1 mm x 5 mm loading column packed with 5 microm Kromasil C18 particles by a carrier solution of 0.1% formic acid in ACN/water (5:95, v/v) at a flow rate of 250 microL/min for online preconcentration of the analytes. Back-flushed elution onto a 150 mm x 0.5 mm Zorbax C18 column packed with 5 microm particles was conducted using a linear solvent ACN/H2O gradient containing 0.1% formic acid. (Tyr8)-bradykinin was used as an internal standard and was added to the dialysis sample prior to injection. Baseline separation of bradykinin, arg-bradykinin and (tyr8)-bradykinin was achieved within 10 min. Positive ESI was performed in the m/z range of 200-1300. The method was validated in the range 0.2-1.0 ng/mL dialysate, yielding correlation coefficients of 0.995 and 0.990 for bradykinin and arg-bradykinin, respectively. The within-assay and between-assay precisions were between 4.3-9.6% and 6.2-10.6%, respectively. Both arg-bradykinin and bradykinin were detected in dialysate from rat muscle tissue, at concentrations of 0.1 and 0.4 ng/mL for bradykinin and arg-bradykinin, respectively, confirming the presence of arg-bradykinin in rat muscles.

  18. Estrogen Receptor α Increases Basal and Cigarette Smoke Extract-Induced Expression of CYP1A1 and CYP1B1, but not GSTP1, in Normal Human Bronchial Epithelial Cells

    PubMed Central

    Han, W; Pentecost, BT; Pietropaolo, RL; Fasco, MJ; Spivack, SD

    2005-01-01

    Gender-specific estrogen receptor α (ERα) expression may plausibly influence lung carcinogenesis in females. Initial genome-wide microarray studies confirmed that carcinogen metabolism genes (CYP1A1, CYP1B1) were those most responsive to cigarette smoke extract (CSE) in normal bronchial epithelial (NHBE) cells. These two genes encoding phase I bioactivating enzymes and the GSTP1 gene encoding a phase II deactivating enzyme were then tested for induction by ERα. NHBE cells (native ERα−) were transfected with wild-type ERα-adenoviral constructs, and then exposed to CSE, 17β-estradiol (E2), and/or the ERα inhibitor, ICI 182,780. The expression levels of CYP1A1, CYP1B1 and GSTP1 were then determined by RNA-specific quantitative RT-PCR and immunoassay. ERα increased the basal expression of CYP1B1 4.04-fold (p<0.01) at the mRNA level and 6.5-fold at the protein level. ERα also increased the CSE-induced mRNA expression of CYP1B1 2.26-fold (p<0.01), but not the protein expression. ERα did not alter the CYP1A1 mRNA levels, but did increase protein expression 2.0-fold (p<0.01) on CSE exposure, and 6.2-fold (p<0.01) upon E2 exposure. These effects could be inhibited by ICI 182,780. ERα did not alter the expression of GSTP1. ChIP assay confirmed ERα binding to CYP1B1 promoter near the transcription start site. These results suggest that ERα regulates the CYP1B1 expression at a transcriptional level, and CYP1A1 expression at a translational level. These data raise the possibility that inter-gender differences in expression of ERα that are known to exist in human lung may contribute to inter-individual expression differences in CYP1A1 and CYP1B1, and to differences in carcinogen metabolism and mutation. PMID:16010691

  19. Identification and functional analysis of a novel bradykinin inhibitory peptide in the venoms of New World Crotalinae pit vipers.

    PubMed

    Graham, Robert Leslie James; Graham, Ciaren; McClean, Stephen; Chen, Tianbao; O'Rourke, Martin; Hirst, David; Theakston, David; Shaw, Chris

    2005-12-23

    A novel undecapeptide has been isolated and structurally characterized from the venoms of three species of New World pit vipers from the subfamily, Crotalinae. These include the Mexican moccasin (Agkistrodon bilineatus), the prairie rattlesnake (Crotalus viridis viridis), and the South American bushmaster (Lachesis muta). The peptide was purified from all three venoms using a combination of gel permeation chromatography and reverse-phase HPLC. Automated Edman degradation sequencing and MALDI-TOF mass spectrometry established its peptide primary structure as: Thr-Pro-Pro-Ala-Gly-Pro-Asp-Val-Gly-Pro-Arg-OH, with a non-protonated molecular mass of 1063.18 Da. A synthetic replicate of the peptide was found to be an antagonist of bradykinin action at the rat vascular B2 receptor. This is the first bradykinin inhibitory peptide isolated from snake venom. Database searching revealed the peptide to be highly structurally related (10/11 residues) with a domain residing between the bradykinin-potentiating peptide and C-type natriuretic peptide domains of a recently cloned precursor from tropical rattlesnake (Crotalus durissus terrificus) venom gland. BIP thus represents a novel biological entity from snake venom.

  20. Identification and functional analysis of a novel bradykinin inhibitory peptide in the venoms of New World Crotalinae pit vipers

    SciTech Connect

    James Graham, Robert Leslie . E-mail: rl.graham@ulster.ac.uk; Graham, Ciaren; McClean, Stephen; Chen, Tianbao; O'Rourke, Martin; Hirst, David; Theakston, David; Shaw, Chris

    2005-12-23

    A novel undecapeptide has been isolated and structurally characterized from the venoms of three species of New World pit vipers from the subfamily, Crotalinae. These include the Mexican moccasin (Agkistrodon bilineatus), the prairie rattlesnake (Crotalus viridis viridis), and the South American bushmaster (Lachesis muta). The peptide was purified from all three venoms using a combination of gel permeation chromatography and reverse-phase HPLC. Automated Edman degradation sequencing and MALDI-TOF mass spectrometry established its peptide primary structure as: Thr-Pro-Pro-Ala-Gly-Pro-Asp-Val-Gly-Pro-Arg-OH, with a non-protonated molecular mass of 1063.18 Da. A synthetic replicate of the peptide was found to be an antagonist of bradykinin action at the rat vascular B2 receptor. This is the first bradykinin inhibitory peptide isolated from snake venom. Database searching revealed the peptide to be highly structurally related (10/11 residues) with a domain residing between the bradykinin-potentiating peptide and C-type natriuretic peptide domains of a recently cloned precursor from tropical rattlesnake (Crotalus durissus terrificus) venom gland. BIP thus represents a novel biological entity from snake venom.

  1. Kinin Receptors Sensitize TRPV4 Channel and Induce Mechanical Hyperalgesia: Relevance to Paclitaxel-Induced Peripheral Neuropathy in Mice.

    PubMed

    Costa, Robson; Bicca, Maíra A; Manjavachi, Marianne N; Segat, Gabriela C; Dias, Fabiana Chaves; Fernandes, Elizabeth S; Calixto, João B

    2017-03-10

    Kinin B1 (B1R) and B2 receptors (B2R) and the transient receptor potential vanilloid 4 (TRPV4) channel are known to play a critical role in the peripheral neuropathy induced by paclitaxel (PTX) in rodents. However, the downstream pathways activated by kinin receptors as well as the sensitizers of the TRPV4 channel involved in this process remain unknown. Herein, we investigated whether kinins sensitize TRPV4 channels in order to maintain PTX-induced peripheral neuropathy in mice. The mechanical hyperalgesia induced by bradykinin (BK, a B2R agonist) or des-Arg(9)-BK (DABK, a B1R agonist) was inhibited by the selective TRPV4 antagonist HC-067047. Additionally, BK was able to sensitize TRPV4, thus contributing to mechanical hyperalgesia. This response was dependent on phospholipase C/protein kinase C (PKC) activation. The selective kinin B1R (des-Arg(9)-[Leu(8)]-bradykinin) and B2R (HOE 140) antagonists reduced the mechanical hyperalgesia induced by PTX, with efficacies and time response profiles similar to those observed for the TRPV4 antagonist (HC-067047). Additionally, both kinin receptor antagonists inhibited the overt nociception induced by hypotonic solution in PTX-injected animals. The same animals presented lower PKCε levels in skin and dorsal root ganglion samples. The selective PKCε inhibitor (εV1-2) reduced the hypotonicity-induced overt nociception in PTX-treated mice with the same magnitude observed for the kinin receptor antagonists. These findings suggest that B1R or B2R agonists sensitize TRPV4 channels to induce mechanical hyperalgesia in mice. This mechanism of interaction may contribute to PTX-induced peripheral neuropathy through the activation of PKCε. We suggest these targets represent new opportunities for the development of effective analgesics to treat chronic pain.

  2. Cloning of the GABAB Receptor Subunits B1 and B2 and their Expression in the Central Nervous System of the Adult Sea Lamprey

    PubMed Central

    Romaus-Sanjurjo, Daniel; Fernández-López, Blanca; Sobrido-Cameán, Daniel; Barreiro-Iglesias, Antón; Rodicio, María Celina

    2016-01-01

    In vertebrates, γ-aminobutyric acid (GABA) is the main inhibitory transmitter in the central nervous system (CNS) acting through ionotropic (GABAA) and metabotropic (GABAB) receptors. The GABAB receptor produces a slow inhibition since it activates second messenger systems through the binding and activation of guanine nucleotide-binding proteins [G-protein-coupled receptors (GPCRs)]. Lampreys are a key reference to understand molecular evolution in vertebrates. The importance of the GABAB receptor for the modulation of the circuits controlling locomotion and other behaviors has been shown in pharmacological/physiological studies in lampreys. However, there is no data about the sequence of the GABAB subunits or their expression in the CNS of lampreys. Our aim was to identify the sea lamprey GABAB1 and GABAB2 transcripts and study their expression in the CNS of adults. We cloned two partial sequences corresponding to the GABAB1 and GABAB2 cDNAs of the sea lamprey as confirmed by sequence analysis and comparison with known GABAB sequences of other vertebrates. In phylogenetic analyses, the sea lamprey GABAB sequences clustered together with GABABs sequences of vertebrates and emerged as an outgroup to all gnathostome sequences. We observed a broad and overlapping expression of both transcripts in the entire CNS. Expression was mainly observed in neuronal somas of the periventricular regions including the identified reticulospinal cells. No expression was observed in identifiable fibers. Comparison of our results with those reported in other vertebrates indicates that a broad and overlapping expression of the GABAB subunits in the CNS is a conserved character shared by agnathans and gnathostomes. PMID:28008311

  3. Bradykinin-activated transmembrane signals are coupled via N/sub o/ or N/sub i/ to production of inositol 1,4,5-trisphosphate, a second messenger in NG108-15 neuroblastoma-glioma hybrid cells

    SciTech Connect

    Higashida, H.; Streaty, R.A.; Klee, W.; Nirenberg, M.

    1986-02-01

    The addition of bradykinin to NG108-15 cells results in a transient hyperpolarization followed by prolonged cell depolarization. Injection of inositol 1,4,5-trisphosphate or CaS into the cytoplasm of NG108-15 cells also elicits cell hyperpolarization followed by depolarization. Tetraethylammonium ions inhibit the hyperpolarizing response of cells to bradykinin or inositol 1,4,5-trisphosphate. Thus, the hyperpolarizing phase of the cell response may be due to inositol 1,4,5-trisphosphate-dependent release of stored UVCa-labelled CaS into the cytoplasm, which activates CaS -dependent K channels. The depolarizing phase of the cell response to bradykinin is due largely to inhibition of M channels, thereby decreasing the rate of K efflux from cells and, to a lesser extent, to activation of CaS -dependent ion channels and CaS channels. In contrast, injection of inositol 1,4,5-trisphosphate or CaS into the cytosol did not alter M channel activity. Incubation of NG108-15 cells with pertussis toxin inhibits bradykinin-dependent cell hyperpolarization and depolarization. Bradykinin stimulates low K/sub m/ GTPase activity and inhibits adenylate cyclase in NG108-15 membrane preparations but not in membranes prepared from cells treated with pertussis toxin. These results show that (bradykinin-receptor) complexes interact with N/sub o/ or N/sub i/ and suggest that N/sub o/ and/or N/sub i/ mediate the transduction of signals from bradykinin receptors to phospholipase C and adenylate cyclase.

  4. Boeing XF2B-1 (F2B-1)

    NASA Technical Reports Server (NTRS)

    1931-01-01

    Boeing XF2B-1 (F2B-1): Serving as the prototype for the F2B-1 shipboard fighter, the XF2B-1 differed visually in having a pointed spinner and an unbalanced rudder. Like many aircraft of its day, the Boeing model 69 was powered by a Pratt & Whitney Wasp radial engine.

  5. Regulation of glucose transport by insulin, bombesin, and bradykinin in Swiss 3T3 fibroblasts: Involvement of protein kinase C-dependent and -independent mechanisms

    SciTech Connect

    Dettori, C.; Meldolesi, J. )

    1989-05-01

    Glucose transport stimulation by insulin, bombesin, and bradykinin in Swiss 3T3 fibroblasts was compared with the phosphoinositide hydrolysis effects of the same stimulants in a variety of experimental paradigms known to affect generation and/or functioning of intracellular second messengers: short- and long-term treatments with phorbol dibutyrate, that cause activation and down-regulation of protein kinase C, respectively; cell loading with high (quin2), that causes clamping of (Ca{sup 2+}){sub i} near the resting level; poisoning with pertussis toxin, that affects the GTP binding proteins of the Go/Gi class; treatment with Ca{sup 2+} ionophores. ({sup 14}C) glucose transport stimulation by maximal (insulin) was affected by neither pertussis toxin nor protein kinase C down-regulation. This result correlates with the lack of effect of insulin on phosphoinositide hydrolysis. In contrast, part of the glucose transport responses induced by bombesin and bradykinin appeared to be mediated by protein kinase C in proportion with the stimulation induced by these peptides on the phosphoinositide hydrolysis. The protein kinase C-independent portion of the response to bradykinin was found to be inhibitable by pertussis toxin. This latter result might suggest an interaction between the bradykinin receptor and a glucose transporter, mediated by a protein of the Go/Gi class.

  6. Ligand-dependent regulation of the activity of the orphan nuclear receptor, small heterodimer partner (SHP), in the repression of bile acid biosynthetic CYP7A1 and CYP8B1 genes.

    PubMed

    Miao, Ji; Choi, Sung-E; Seok, Sun Mi; Yang, Linda; Zuercher, William J; Xu, Yong; Willson, Timothy M; Xu, H Eric; Kemper, Jongsook Kim

    2011-07-01

    Small heterodimer partner (SHP) plays important roles in diverse biological processes by directly interacting with transcription factors and inhibiting their activities. SHP has been designated an orphan nuclear receptor, but whether its activity can be modulated by ligands has been a long-standing question. Recently, retinoid-related molecules, including 4-[3-(1-adamantyl)-4-hydroxyphenyl]-3-chlorocinnamic acid (3Cl-AHPC), were shown to bind to SHP and enhance apoptosis. We have examined whether 3Cl-AHPC acts as an agonist and increases SHP activity in the repression of bile acid biosynthetic CYP7A1 and CYP8B1 genes and delineated the underlying mechanisms. Contrary to this expectation, micromolar concentrations of 3Cl-AHPC increased CYP7A1 expression but indirectly via p38 kinase signaling. Nanomolar concentrations, however, repressed CYP7A1 expression and decreased bile acid levels in HepG2 cells, and little repression was observed when SHP was down-regulated by small hairpin RNA. Mechanistic studies revealed that 3Cl-AHPC bound to SHP, increased the interaction of SHP with liver receptor homologue (LRH)-1, a hepatic activator for CYP7A1 and CYP8B1 genes, and with repressive cofactors, Brahma, mammalian Sin3a, and histone deacetylase-1, and, subsequently, increased the occupancy of SHP and these cofactors at the promoters. Mutation of Leu-100, predicted to contact 3Cl-AHPC within the SHP ligand binding pocket by molecular modeling, severely impaired the increased interaction with LRH-1, and repression of LRH-1 activity mediated by 3Cl-AHPC. 3Cl-AHPC repressed SHP metabolic target genes in a gene-specific manner in human primary hepatocytes and HepG2 cells. These data suggest that SHP may act as a ligand-regulated receptor in metabolic pathways. Modulation of SHP activity by synthetic ligands may be a useful therapeutic strategy.

  7. DNA-Encoded Library Screening Identifies Benzo[b][1,4]oxazepin-4-ones as Highly Potent and Monoselective Receptor Interacting Protein 1 Kinase Inhibitors.

    PubMed

    Harris, Philip A; King, Bryan W; Bandyopadhyay, Deepak; Berger, Scott B; Campobasso, Nino; Capriotti, Carol A; Cox, Julie A; Dare, Lauren; Dong, Xiaoyang; Finger, Joshua N; Grady, LaShadric C; Hoffman, Sandra J; Jeong, Jae U; Kang, James; Kasparcova, Viera; Lakdawala, Ami S; Lehr, Ruth; McNulty, Dean E; Nagilla, Rakesh; Ouellette, Michael T; Pao, Christina S; Rendina, Alan R; Schaeffer, Michelle C; Summerfield, Jennifer D; Swift, Barbara A; Totoritis, Rachel D; Ward, Paris; Zhang, Aming; Zhang, Daohua; Marquis, Robert W; Bertin, John; Gough, Peter J

    2016-03-10

    The recent discovery of the role of receptor interacting protein 1 (RIP1) kinase in tumor necrosis factor (TNF)-mediated inflammation has led to its emergence as a highly promising target for the treatment of multiple inflammatory diseases. We screened RIP1 against GSK's DNA-encoded small-molecule libraries and identified a novel highly potent benzoxazepinone inhibitor series. We demonstrate that this template possesses complete monokinase selectivity for RIP1 plus unique species selectivity for primate versus nonprimate RIP1. We elucidate the conformation of RIP1 bound to this benzoxazepinone inhibitor driving its high kinase selectivity and design specific mutations in murine RIP1 to restore potency to levels similar to primate RIP1. This series differentiates itself from known RIP1 inhibitors in combining high potency and kinase selectivity with good pharmacokinetic profiles in rodents. The favorable developability profile of this benzoxazepinone template, as exemplified by compound 14 (GSK'481), makes it an excellent starting point for further optimization into a RIP1 clinical candidate.

  8. The chromatographic behaviour of wasp venom kinin, kallidin and bradykinin.

    PubMed

    MATHIAS, A P; SCHACHTER, M

    1958-09-01

    Wasp venom kinin which has hitherto appeared to be homogeneous can be resolved by ionexchange chromatography into a single major and two minor components. These are indistinguishable by their action on smooth muscle and by their rapid inactivation by chymotrypsin. All three components of wasp kinin are chromatographically different from kallidin or bradykinin. The close similarity of the latter compounds is confirmed by their identical behaviour on an ion-exchange resin.

  9. Mechanism of contraction induced by bradykinin in the rabbit saphenous vein

    PubMed Central

    Eguchi, Daihiko; Nishimura, Junji; Kobayashi, Sei; Komori, Kimihiro; Sugimachi, Keizo; Kanaide, Hideo

    1997-01-01

    By using fura-PE3 fluorometry and receptor-coupled permeabilization by α-toxin, the mechanism of the bradykinin (BK)-induced contraction was determined in the rabbit saphenous vein (RSV). The receptor subtype responsible for the BK-induced contraction of RSV was determined by means of a pharmacological blocker study and reverse transcription polymerase chain reaction (RT-PCR).In the presence of extracellular Ca2+ (1.25 mM), BK (10−11–3×10−7 M) induced increases in both the cytosolic Ca2+ concentration ([Ca2+]i) and force, in a concentration-dependent manner. Both the release of Ca2+ from the store site and the influx of extracellular Ca2+ contribute to an increase in [Ca2+]i induced by BK.In the absence of extracellular Ca2+, the application of 10−7 M BK induced transient elevations of [Ca2+]i and force, both of which thereafter declined to the levels observed before the application of BK. When extracellular Ca2+ was replenished (1.25 mM), [Ca2+]i and force increased to form a peak, followed by a sustained elevation in the presence of BK. When an RSV strip was pretreated with 10−5 M thapsigargin for 20 min, the BK-induced transient increases in both [Ca2+]i and force were markedly inhibited.These responses induced by BK were inhibited by Hoe 140 (D-Arg-[Hyp3, Thi5, D-Tic7, Oic8] bradykinin), a highly specific bradykinin B2 receptor antagonist, in a concentration-dependent manner. In RT-PCR, B2-receptor mRNA was expressed in the smooth muscle of RSV.The [Ca2+]i-force relationships, which were determined by cumulative applications of extracellular Ca2+ (0–5 mM) during 118 mM K+-depolarization, shifted to the upper left in the presence of BK, thus indicating that BK induced a greater force than 118 mM K+-depolarization for a given level of [Ca2+]i.In α-toxin-permeabilized preparations of RSV, application of 10−7 M BK after a steady state contraction had been induced by a mixture of 5×10−7 M Ca2+, 10−6 M GTP and 10−6

  10. Relationship between bradykinin-induced relaxation and endogenous epoxyeicosanoid synthesis in human bronchi.

    PubMed

    Tabet, Yacine; Sirois, Marco; Sirois, Chantal; Rizcallah, Edmond; Rousseau, Éric

    2013-04-15

    Epoxyeicosanoids (EETs) are produced by cytochrome P-450 epoxygenase; however, it is not yet known what triggers their endogenous production in epithelial cells. The relaxing effects of bradykinin are known to be related to endogenous production of epithelial-derived hyperpolarizing factors (EpDHF). Because of their effects on membrane potential, EETs have been reported to be EpDHF candidates (Benoit C, Renaudon B, Salvail D, Rousseau E. Am J Physiol Lung Cell Mol Physiol 280: L965-L973, 2001.). Thus, we hypothesized that bradykinin (BK) may stimulate endogenous EET production in human bronchi. To test this hypothesis, the relaxing and hyperpolarizing effects of BK and 14,15-EET were quantified on human bronchi, as well as the effects of various enzymatic inhibitors on these actions. One micromolar BK or 1 μM 14,15-EET induced a 45% relaxation on the tension induced by 30 nM U-46619 [a thromboxane-prostanoid (TP)-receptor agonist]. These BK-relaxing effects were reduced by 42% upon addition of 10 nM iberiotoxin [a large-conductance Ca(2+)-sensitive K(+) (BK(Ca)) channel blocker], by 27% following addition of 3 μM 14,15-epoxyeicosa-5(Z)-enoic acid (an EET antagonist), and by 32% with 3 μM N-methanesulfonyl-6-(2-propargyloxyphenyl)hexanamide (MS-PPOH, an epoxygenase inhibitor). Hence, BK and 14,15-EET display net hyperpolarizing effects on airway smooth muscle cells that are related to the activation of BK(Ca) channels and ultimately yielding to relaxation. Data also indicate that 3 μM MS-PPOH reduced the hyperpolarizing effects of BK by 43%. Together, the present data support the current hypothesis suggesting a direct relationship between BK and the production of EET regioisomers. Because of its potent anti-inflammatory and relaxing properties, epoxyeicosanoid signaling may represent a promising target in asthma and chronic obstructive pulmonary disease.

  11. Neurophysiological mechanisms of bradykinin-evoked mucosal chloride secretion in guinea pig small intestine

    PubMed Central

    Qu, Mei-Hua; Ji, Wan-Sheng; Zhao, Ting-Kun; Fang, Chun-Yan; Mao, Shu-Mei; Gao, Zhi-Qin

    2016-01-01

    AIM: To investigate the mechanism for bradykinin (BK) to stimulate intestinal secretomotor neurons and intestinal chloride secretion. METHODS: Muscle-stripped guinea pig ileal preparations were mounted in Ussing flux chambers for the recording of short-circuit current (Isc). Basal Isc and Isc stimulated by BK when preincubated with the BK receptors antagonist and other chemicals were recorded using the Ussing chamber system. Prostaglandin E2 (PGE2) production in the intestine was determined by enzyme immunologic assay (EIA). RESULTS: Application of BK or B2 receptor (B2R) agonist significantly increased the baseline Isc compared to the control. B2R antagonist, tetrodotoxin and scopolamine (blockade of muscarinic receptors) significantly suppressed the increase in Isc evoked by BK. The BK-evoked Isc was suppressed by cyclooxygenase (COX)-1 or COX-2 specific inhibitor as well as nonselective COX inhibitors. Preincubation of submucosa/mucosa preparations with BK for 10 min significantly increased PGE2 production and this was abolished by the COX-1 and COX-2 inhibitors. The BK-evoked Isc was suppressed by nonselective EP receptors and EP4 receptor antagonists, but selective EP1 receptor antagonist did not have a significant effect on the BK-evoked Isc. Inhibitors of PLC, PKC, calmodulin or CaMKII failed to suppress BK-induced PGE2 production. CONCLUSION: The results suggest that BK stimulates neurogenic chloride secretion in the guinea pig ileum by activating B2R, through COX increasing PGE2 production. The post-receptor transduction cascade includes activation of PLC, PKC, CaMK, IP3 and MAPK. PMID:26909238

  12. Bradykinin-induced chemotaxis of human gliomas requires the activation of KCa3.1 and ClC-3

    PubMed Central

    Cuddapah, Vishnu Anand; Turner, Kathryn L.; Seifert, Stefanie; Sontheimer, Harald

    2013-01-01

    Previous reports demonstrate that cell migration in the nervous system is associated with stereotypic changes in intracellular calcium concentration ([Ca2+]i), yet the target of these changes are largely unknown. We examined chemotactic migration/invasion of human gliomas to study how [Ca2+]i regulates cellular movement and to identify downstream targets. Gliomas are primary brain cancers which spread exclusively within the brain, frequently migrating along blood vessels to which they are chemotactically attracted by bradykinin activating G protein-coupled receptors. Using simultaneous Fura-2 Ca2+ imaging and amphotericin B perforated patch-clamp electrophysiology, we find that bradykinin raises [Ca2+]i and induces a biphasic voltage response. This voltage response is mediated by the coordinated activation of Ca2+-dependent, TRAM-34-sensitive KCa3.1 channels, and Ca2+-depdenent, DIDS- and gluconate-sensitive Cl− channels. A significant portion of these Cl− currents can be attributed to Ca2+/calmodulin-dependent protein kinase II (CaMKII) activation of ClC-3, a voltage-gated Cl−channel/transporter, since pharmacological inhibition of CaMKII or shRNA-mediated knockdown of ClC-3 inhibited Ca2+-activated Cl− currents. Western blots show that KCa3.1 and ClC-3 are expressed in tissue samples obtained from patients diagnosed with Grade IV gliomas. Both KCa3.1 and ClC-3 co-localize to the invading processes of glioma cells. Importantly, inhibition of either channel abrogates bradykinin-induced chemotaxis and reduces tumor expansion in mouse brain slices in situ. These channels should be further explored as future targets for anti-invasive drugs. Furthermore, this data elucidates a novel mechanism placing cation and anion channels downstream of ligand-mediated [Ca2+]i increases, which likely play similar roles in other migratory cells in the nervous system. PMID:23345219

  13. Endothelium-Derived Hyperpolarizing Factor Mediates Bradykinin Stimulated Tissue Plasminogen Activator Release In Humans

    PubMed Central

    Rahman, Ayaz M.; Murrow, Jonathan R.; Ozkor, Muhiddin A.; Kavtaradze, Nino; Lin, Ji; De Staercke, Christine; Hooper, W. Craig; Manatunga, Amita; Hayek, Salim; Quyyumi, Arshed A.

    2014-01-01

    Aims Bradykinin stimulates tissue plasminogen activator (t-PA) release from human endothelium. Although bradykinin stimulates both nitric oxide and endothelium-derived hyperpolarizing factor (EDHF) release, the role of EDHF in t-PA release remains unexplored. This study sought to determine the mechanisms of bradykinin-stimulated t-PA release in the forearm vasculature of healthy human subjects. Methods In 33 healthy subjects (age 40.3±1.9 years) forearm blood flow (FBF) and t-PA release were measured at rest, and after intra-arterial infusions of bradykinin (400ng/min) and sodium nitroprusside (3.2 mg/min). Measurements were repeated after intra-arterial infusion of TEA (1 μmol/min), fluconazole (0.4 μmol.min-1.L-1), and NG-monomethyl-L-arginine (L-NMMA, 8 μmol/min) to block nitric oxide, and their combination in separate studies. Results Bradykinin significantly increased net t-PA release across the forearm (P<0.0001). Fluconazole attenuated both bradykinin-mediated vasodilation (-23.3±2.7% FBF, P<0.0001) and t-PA release (from 50.9±9.0 to 21.3±8.9 ng/min/100ml, P=0.02). TEA attenuated FBF (-14.7±3.2%, P=0.002) and abolished bradykinin-stimulated t-PA release (from 22.9+5.7 to - 0.8±3.6 ng/min/100ml, P=0.0002). L-NMMA attenuated FBF (P<0.0001), but did not inhibit bradykinin-induced t-PA release (P=NS). Conclusion Bradykinin-stimulated t-PA release is partly due to cytochrome P450-derived epoxides, and is inhibited by K+ca channel blockade. Thus, bradykinin stimulates both EDHF-dependent vasodilation and t-PA release. PMID:24925526

  14. Boeing F3B-1

    NASA Technical Reports Server (NTRS)

    1930-01-01

    Boeing F3B-1: While most Boeing F3B-1s served aboard the U. S. Navy aircraft carriers Lexington and Saratoga, this example flew in NACA hands at the Langley Memorial Aeronautical Laboratory in the late 1920's. Also known as the Boeing Model 77, the aircraft was powered by a Pratt & Whitney Wasp radial engine.

  15. Noxious cold ion channel TRPA1 is activated by pungent compounds and bradykinin.

    PubMed

    Bandell, Michael; Story, Gina M; Hwang, Sun Wook; Viswanath, Veena; Eid, Samer R; Petrus, Matt J; Earley, Taryn J; Patapoutian, Ardem

    2004-03-25

    Six members of the mammalian transient receptor potential (TRP) ion channels respond to varied temperature thresholds. The natural compounds capsaicin and menthol activate noxious heat-sensitive TRPV1 and cold-sensitive TRPM8, respectively. The burning and cooling perception of capsaicin and menthol demonstrate that these ion channels mediate thermosensation. We show that, in addition to noxious cold, pungent natural compounds present in cinnamon oil, wintergreen oil, clove oil, mustard oil, and ginger all activate TRPA1 (ANKTM1). Bradykinin, an inflammatory peptide acting through its G protein-coupled receptor, also activates TRPA1. We further show that phospholipase C is an important signaling component for TRPA1 activation. Cinnamaldehyde, the most specific TRPA1 activator, excites a subset of sensory neurons highly enriched in cold-sensitive neurons and elicits nociceptive behavior in mice. Collectively, these data demonstrate that TRPA1 activation elicits a painful sensation and provide a potential molecular model for why noxious cold can paradoxically be perceived as burning pain.

  16. Bradykinin promotes vascular endothelial growth factor expression and increases angiogenesis in human prostate cancer cells.

    PubMed

    Yu, Hsin-Shan; Wang, Shih-Wei; Chang, An-Chen; Tai, Huai-Ching; Yeh, Hung-I; Lin, Yu-Min; Tang, Chih-Hsin

    2014-01-15

    Prostate cancer is the most commonly diagnosed malignancy in men and shows a tendency for metastasis to distant organs. Angiogenesis is required for metastasis. Bradykinin (BK) is an inflammatory mediator involved in tumor growth and metastasis, but its role in vascular endothelial growth factor (VEGF) expression and angiogenesis in human prostate cancer remains unknown. The aim of this study was to examine whether BK promotes prostate cancer angiogenesis via VEGF expression. We found that exogenous BK increased VEGF expression in prostate cancer cells and further promoted tube formation in endothelial progenitor cells and human umbilical vein endothelial cells. Pretreatment of prostate cancer with B2 receptor antagonist or small interfering RNA (siRNA) reduced BK-mediated VEGF production. The Akt and mammalian target of rapamycin (mTOR) pathways were activated after BK treatment, and BK-induced VEGF expression was abolished by the specific inhibitor and siRNA of the Akt and mTOR cascades. BK also promoted nuclear factor-κB (NF-κB) and activator protein 1 (AP-1) activity. Importantly, BK knockdown reduced VEGF expression and abolished prostate cancer cell conditional medium-mediated angiogenesis. Taken together, these results indicate that BK operates through the B2 receptor, Akt, and mTOR, which in turn activate NF-κB and AP-1, activating VEGF expression and contributing to angiogenesis in human prostate cancer cells.

  17. Cardiovascular actions of python bradykinin and substance P in the anesthetized python, Python regius.

    PubMed

    Wang, T; Axelsson, M; Jensen, J; Conlon, J M

    2000-08-01

    The cardiovascular actions of python bradykinin (BK) and substance P (SP) have been investigated in the anesthetized ball python, Python regius. Bolus intra-arterial injections of python BK (0.03-3 nmol/kg) produced concentration-dependent increases in arterial blood pressure, heart rate (HR), and cardiac output concomitant with small decreases in systemic resistance and stroke volume. Intra-arterial injection of 3 nmol/kg python BK produced a tenfold increase in circulating concentration of norepinephrine, but epinephrine levels did not change. BK-induced tachycardia was attenuated (>90%) by the beta-adrenergic receptor antagonist sotalol, and the hypertensive response was attenuated (>70%) by the alpha-adrenergic receptor antagonist prazosin, indicating that effects of python BK are mediated at least in part by activation of the extensive network of adrenergic neurons present in vascular tissues. Bolus intra-arterial injections of python SP in the range 0. 01-30 pmol/kg produced concentration-dependent decreases in arterial blood pressure and systemic peripheral resistance concomitant with increases in cardiac output and stroke volume but with only minor effects on HR. The data suggest that kinins play a physiologically important role in cardiovascular regulation in the python.

  18. Sensitization of neonatal rat lumbar motoneuron by the inflammatory pain mediator bradykinin

    PubMed Central

    Bouhadfane, Mouloud; Kaszás, Attila; Rózsa, Balázs; Harris-Warrick, Ronald M; Vinay, Laurent; Brocard, Frédéric

    2015-01-01

    Bradykinin (Bk) is a potent inflammatory mediator that causes hyperalgesia. The action of Bk on the sensory system is well documented but its effects on motoneurons, the final pathway of the motor system, are unknown. By a combination of patch-clamp recordings and two-photon calcium imaging, we found that Bk strongly sensitizes spinal motoneurons. Sensitization was characterized by an increased ability to generate self-sustained spiking in response to excitatory inputs. Our pharmacological study described a dual ionic mechanism to sensitize motoneurons, including inhibition of a barium-sensitive resting K+ conductance and activation of a nonselective cationic conductance primarily mediated by Na+. Examination of the upstream signaling pathways provided evidence for postsynaptic activation of B2 receptors, G protein activation of phospholipase C, InsP3 synthesis, and calmodulin activation. This study questions the influence of motoneurons in the assessment of hyperalgesia since the withdrawal motor reflex is commonly used as a surrogate pain model. DOI: http://dx.doi.org/10.7554/eLife.06195.001 PMID:25781633

  19. Acute effect of inhaled bradykinin on tracheobronchial clearance in normal humans.

    PubMed Central

    Polosa, R; Hasani, A; Pavia, D; Agnew, J E; Lai, C K; Clarke, S W; Holgate, S T

    1992-01-01

    BACKGROUND: Bradykinin, a nonapeptide that contributes as a mediator to the pathogenesis of asthma, may affect lung mucociliary clearance, as it has been shown to be a potent secretagogue in canine airways and in human nasal mucosa in vivo. To evaluate this possibility the effect of inhaled bradykinin on mucociliary clearance has been studied in 10 healthy volunteers. METHODS: Subjects attended the laboratory on two occasions to take part in tracheobronchial clearance studies using a non-invasive radioisotopic technique. Inhalation of radioaerosol was followed 30 minutes later by inhalation of either bradykinin (8 mg/ml) or vehicle placebo in a randomised, double blind fashion. After each inhalation the number of coughs was recorded. Whole lung radioactivity was measured every half hour for six hours with two collimated scintillation counters, and a tracheobronchial clearance curve was plotted for each subject on each occasion. RESULTS: Mucociliary clearance, expressed as the area under the tracheobronchial radioaerosol retention curve calculated for the first six hours (AUC0-6h), was greater in nine out of 10 subjects after inhalation of bradykinin than after placebo. The median values (range) for AUC0-6h were significantly reduced from 126% (78-232%)/h with placebo to 87% (51-133%)/h with bradykinin. CONCLUSION: It is concluded that acute exposure to inhaled bradykinin accelerates tracheobronchial clearance in normal human airways. PMID:1465754

  20. Metalloendopeptidases EC 3.4.24.15/16 regulate bradykinin activity in the cerebral microvasculature.

    PubMed

    Norman, M Ursula; Lew, Rebecca A; Smith, A Ian; Hickey, Michael J

    2003-06-01

    Bradykinin is a vasoactive peptide that has been shown to increase the permeability of the cerebral microvasculature to blood-borne macromolecules. The two zinc metalloendopeptidases EC (EP 24.15) and EC (EP 24.16) degrade bradykinin in vitro and are highly expressed in the brain. However, the role that these enzymes play in bradykinin metabolism in vivo remains unclear. In the present study, we investigated the role of EP 24.15 and EP 24.16 in the regulation of bradykinin-induced alterations in microvascular permeability. Permeability of the cerebral microvasculature was assessed in anesthetized Sprague-Dawley rats by measuring the clearance of 70-kDa FITC dextran from the brain. Inhibition of EP 24.15 and EP 24.16 by the specific inhibitor N-[1-(R,S)-carboxy-3-phenylpropyl]-Ala-Aib-Tyr-p-aminobenzoate (JA-2) resulted in the potentiation of bradykinin-induced increases in cerebral microvessel permeability. The level of potentiation was comparable to that achieved by the inhibition of angiotensin-converting enzyme. These findings provide the first evidence of an in vivo role for EP 24.15/EP 24.16 in brain function, specifically in regulating alterations in microvessel permeability induced by exogenous bradykinin.

  1. Multiple bradykinin-related peptides from the capture web of the spider Nephila clavipes (Araneae, Tetragnatidae).

    PubMed

    Volsi, Evelyn C F R; Mendes, Maria Anita; Marques, Maurício Ribeiro; dos Santos, Lucilene Delazari; Santos, Keity Souza; de Souza, Bibiana Monson; Babieri, Eduardo Feltran; Palma, Mario Sergio

    2006-04-01

    Three bradykinin-related peptides (nephilakinins-I to -III) and bradykinin itself were isolated from the aqueous washing extract of the capture web of the spider Nephila clavipes by gel permeation chromatography on a Sephacryl S-100 column, followed by chromatography in a Hi-Trap Sephadex-G25 Superfine column. The novel peptides occurred in low concentrations and were sequenced through ESI-MS/MS analysis: nephilakinin-I (G-P-N-P-G-F-S-P-F-R-NH2), nephilakinin-II (E-A-P-P-G-F-S-P-F-R-NH2) and nephilakinin-III (P-S-P-P-G-F-S-P-F-R-NH2). Synthetic peptides replicated the novel bradykinin-related peptides, which were submitted to biological characterizations. Nephilakinins were shown to cause constriction on isolated rat ileum preparations and relaxation on rat duodenum muscle preparations at amounts higher than bradykinin; apparently these peptides constitute B2-type agonists of ileal and duodenal smooth muscles. All peptides including the bradykinin were moderately lethal to honeybees. These bradykinin peptides may be related to the predation of insects by the webs of N. clavipes.

  2. Developmental acceleration of bradykinin-dependent relaxation by prenatal chronic hypoxia impedes normal development after birth

    PubMed Central

    Blum-Johnston, Carla; Thorpe, Richard B.; Wee, Chelsea; Romero, Monica; Brunelle, Alexander; Blood, Quintin; Blood, Arlin B.; Francis, Michael; Taylor, Mark S.; Longo, Lawrence D.; Pearce, William J.; Wilson, Sean M.

    2015-01-01

    Bradykinin-induced activation of the pulmonary endothelium triggers nitric oxide production and other signals that cause vasorelaxation, including stimulation of large-conductance Ca2+-activated K+ (BKCa) channels in myocytes that hyperpolarize the plasma membrane and decrease intracellular Ca2+. Intrauterine chronic hypoxia (CH) may reduce vasorelaxation in the fetal-to-newborn transition and contribute to pulmonary hypertension of the newborn. Thus we examined the effects of maturation and CH on the role of BKCa channels during bradykinin-induced vasorelaxation by examining endothelial Ca2+ signals, wire myography, and Western immunoblots on pulmonary arteries isolated from near-term fetal (∼140 days gestation) and newborn, 10- to 20-day-old, sheep that lived in normoxia at 700 m or in CH at high altitude (3,801 m) for >100 days. CH enhanced bradykinin-induced relaxation of fetal vessels but decreased relaxation in newborns. Endothelial Ca2+ responses decreased with maturation but increased with CH. Bradykinin-dependent relaxation was sensitive to 100 μM nitro-l-arginine methyl ester or 10 μM 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, supporting roles for endothelial nitric oxide synthase and soluble guanylate cyclase activation. Indomethacin blocked relaxation in CH vessels, suggesting upregulation of PLA2 pathways. BKCa channel inhibition with 1 mM tetraethylammonium reduced bradykinin-induced vasorelaxation in the normoxic newborn and fetal CH vessels. Maturation reduced whole cell BKCa channel α1-subunit expression but increased β1-subunit expression. These results suggest that CH amplifies the contribution of BKCa channels to bradykinin-induced vasorelaxation in fetal sheep but stunts further development of this vasodilatory pathway in newborns. This involves complex changes in multiple components of the bradykinin-signaling axes. PMID:26637638

  3. Modulation of bradykinin signaling by EP24.15 and EP24.16 in cultured trigeminal ganglia.

    PubMed

    Jeske, Nathaniel A; Berg, Kelly A; Cousins, Joanne C; Ferro, Emer S; Clarke, William P; Glucksman, Marc J; Roberts, James L

    2006-04-01

    Metalloendopeptidases expressed in neural tissue are characterized in terms of their neuropeptide substrates. One such neuropeptide, bradykinin (BK), is an important inflammatory mediator that activates the type-2 BK receptor (B2R) on the terminal endings of specialized pain-sensing neurons known as nociceptors. Among several metalloendopeptidases that metabolize and inactivate BK, EP24.15 and EP24.16 are known to associate with the plasma membrane in several immortalized cell lines. Potentially, the colocalization of EP24.15/16 and B2R at plasma membrane microdomains known as lipid rafts in a physiologically relevant nociceptive system would allow for discrete, peptidase regulation of BK signaling. Western blot analysis of crude subcellular fractions and lipid raft preparations of cultured rat trigeminal ganglia demonstrate similar expression profiles between EP24.15/16 and B2R on a subcellular level. Furthermore, the treatment of primary cultures of trigeminal ganglia with inhibitors of EP24.15/16 led to the potentiation of several bradykinin-induced events that occur downstream of B2R activation. EP24.15/16 inhibition by N-[1(R,S)-carboxy-3-phenylpropyl]-Ala-AlalTyr-p-aminobenzoate (cFP) resulted in a 1000-fold increase in B2R sensitivity to BK as measured by inositol phosphate accumulation. In addition, cFP treatment resulted in a 31.1+/-5.0% potentiation of the ability of BK to inhibit protein kinase B (Akt) activity. Taken together, these data demonstrate that EP24.15/16 modulate intracellular, peptidergic signaling cascades through B2R in a physiologically relevant nociceptive system.

  4. Bradykinin-induced bronchoconstriction: inhibition by nedocromil sodium and sodium cromoglycate.

    PubMed Central

    Dixon, C M; Barnes, P J

    1989-01-01

    1. The effects of inhaled nedocromil sodium and sodium cromoglycate on bradykinin-induced bronchoconstriction have been studied in a double-blind, placebo controlled study, in eight mild asthmatic subjects. 2. The subjects attended on four occasions. Fifteen minutes after drug pre-treatment a bradykinin challenge was performed. Increasing concentrations were inhaled until a greater than 40% fall in expiratory flow at 30% of vital capacity from a partial flow volume manoeuvre (V p30) was demonstrated. 3. Inhaled bradykinin (0.06-8.0 mg ml-1) caused dose-related bronchoconstriction with the geometric mean cumulative dose causing a 40% fall in V p30 (PD40) of 0.035 (95% CI: 0.02-0.07) mumol, after placebo inhalation, which was similar to that measured before the trial (0.04: 0.02-0.09 mumol). 4. Both nedocromil sodium (4 mg) and sodium cromoglycate (10 mg) gave significant protection (P less than 0.05) against bradykinin-induced bronchoconstriction (PD40 0.37: 0.19-0.72 mumol after nedocromil sodium and 0.22: 0.11-0.49 after sodium cromoglycate). 5. Since bradykinin-induced bronchoconstriction is probably neurally mediated we conclude that both nedocromil sodium and sodium cromoglycate have an action on neural pathways which may be useful in the control of asthma symptoms. PMID:2547408

  5. Afferent fibers involved in the bradykinin-induced cardiovascular reflexes from the ovary in rats.

    PubMed

    Uchida, Sae; Kagitani, Fusako; Hotta, Harumi

    2015-12-01

    Bleeding or rupture of the ovary often accompanies ovarian cysts and causes severe pain and autonomic responses such as hypotension. It would be expected that ovarian afferents contribute to cardiovascular responses induced by ovarian failure. The present study examined cardiovascular responses to noxious chemical stimulation of the ovary by bradykinin, an algesic substance released by tissue damage, and explored the role of ovarian afferents in the ovarian-cardiovascular responses in anesthetized rats. Non-pregnant adult rats were anesthetized with pentobarbital and artificially ventilated. The carotid artery was cannulated to monitor blood pressure and heart rate. Noxious chemical stimulation was achieved by applying a small piece of cotton soaked with bradykinin to the surface of the ovary for 30s. Application of bradykinin (10(-4) M) to the ovary decreased heart rate and blood pressure. These cardiovascular responses were not significantly influenced by severance of the vagal nerves or the superior ovarian nerve, but were abolished by severance of the ovarian nerve plexus (ONP). Application of bradykinin (10(-4) M) to the ovary evoked afferent activity of the ONP both in vivo and in vitro preparations. These results indicate that the decreases in heart rate and blood pressure following chemical noxious stimulation of the ovary with bradykinin are reflex responses, whose afferent nerve pathway is mainly through afferent fibers in the ONP.

  6. Local L-NG-monomethyl-arginine attenuates the vasodilator action of bradykinin in the human forearm.

    PubMed Central

    O'Kane, K P; Webb, D J; Collier, J G; Vallance, P J

    1994-01-01

    1. Studies in animals indicate that bradykinin relaxes blood vessels directly through an action on smooth muscle and indirectly through the release of endothelium-derived mediators. Its precise mechanism of action in the human arterial circulation is not yet known. 2. In this study the effects of a specific inhibitor of nitric oxide synthase, L-NG-monomethyl-arginine (L-NMMA) and noradrenaline on the vasodilator responses to bradykinin were examined in the forearm arterial bed of healthy volunteers. Noradrenaline was used as a control for vasoconstriction by L-NMMA; glyceryl trinitrate (GTN) as a control vasodilator acting independently of the NO synthase enzyme. 3. L-NMMA (4 mumol min-1; 5 min) alone reduced resting forearm blood flow by 44% (P < 0.01; n = 6) confirming that nitric oxide plays an important role in regulating vascular tone. 4. Bradykinin (10 and 100 pmol min-1; 3 min each dose) and GTN (2 and 5 nmol min-1; 3 min each dose) increased forearm blood flow in a dose-dependent manner (percentage changes 171 +/- 17% and 398 +/- 35%, and 176 +/- 21% and 268 +/- 42%, respectively; n = 6). 5. The response to bradykinin, but not that to GTN, was attenuated by L-NMMA compared with noradrenaline (P < 0.05; n = 6), suggesting that bradykinin-induced vasodilatation in the forearm is mediated, at least in part, by stimulating release of nitric oxide. PMID:7833219

  7. SerpinB1 Promotes Pancreatic β Cell Proliferation

    SciTech Connect

    El Ouaamari, Abdelfattah; Dirice, Ercument; Gedeon, Nicholas; Hu, Jiang; Zhou, Jian-Ying; Shirakawa, Jun; Hou, Lifei; Goodman, Jessica; Karampelias, Christos; Qiang, Guifeng; Boucher, Jeremie; Martinez, Rachael; Gritsenko, Marina A.; De Jesus, Dario F.; Kahraman, Sevim; Bhatt, Shweta; Smith, Richard D.; Beer, Hans-Dietmar; Jungtrakoon, Prapaporn; Gong, Yanping; Goldfine, Allison B.; Liew, Chong Wee; Doria, Alessandro; Andersson, Olov; Qian, Wei-Jun; Remold-O’Donnell, Eileen; Kulkarni, Rohit N.

    2016-01-01

    Compensatory β-cell growth in response to insulin resistance is a common feature in diabetes. We recently reported that liver-derived factors participate in this compensatory response in the liver insulin receptor knockout (LIRKO) mouse, a model of significant islet hyperplasia. Here we show that serpinB1 is a liver-derived secretory protein that controls β-cell proliferation. SerpinB1 is abundant in the hepatocyte secretome and sera derived from LIRKO mice. SerpinB1 and small molecule compounds that partially mimic serpinB1 activity enhanced proliferation of zebrafish, mouse and human β-cells. We report that serpinB1-induced β-cell replication requires protease inhibition activity and mice lacking serpinB1 exhibit attenuated β-cell replication in response to insulin resistance. Finally, SerpinB1-treatment of islets modulated signaling proteins in growth and survival pathways such as MAPK, PKA and GSK3. Together, these data implicate SerpinB1 as a protein that can potentially be harnessed to enhance functional β-cell mass in patients with diabetes.

  8. Inflammatory mediator bradykinin increases population of sensory neurons expressing functional T-type Ca2+ channels

    PubMed Central

    Huang, Dongyang; Liang, Ce; Zhang, Fan; Men, Hongchao; Du, Xiaona; Gamper, Nikita; Zhang, Hailin

    2016-01-01

    T-type Ca2+ channels are important regulators of peripheral sensory neuron excitability. Accordingly, T-type Ca2+ currents are often increased in various pathological pain conditions, such as inflammation or nerve injury. Here we investigated effects of inflammation on functional expression of T-type Ca2+ channels in small-diameter cultured dorsal root ganglion (DRG) neurons. We found that overnight treatment of DRG cultures with a cocktail of inflammatory mediators bradykinin (BK), adenosine triphosphate (ATP), norepinephrine (NE) and prostaglandin E2 (PGE2) strongly increased the population size of the small-diameter neurons displaying low-voltage activated (LVA, T-type) Ca2+ currents while having no effect on the peak LVA current amplitude. When applied individually, BK and ATP also increased the population size of LVA-positive neurons while NE and PGE2 had no effect. The PLC inhibitor U-73122 and B2 receptor antagonist, Hoe-140, both abolished the increase of the population of LVA-positive DRG neurons. Inflammatory treatment did not affect CaV3.2 mRNA or protein levels in DRG cultures. Furthermore, an ubiquitination inhibitor, MG132, did not increase the population of LVA-positive neurons. Our data suggest that inflammatory mediators BK and ATP increase the abundance of LVA-positive DRG neurons in total neuronal population by stimulating the recruitment of a ‘reserve pool’ of CaV3.2 channels, particularly in neurons that do not display measurable LVA currents under control conditions. PMID:26944020

  9. Mechanisms of bradykinin-induced expression of connective tissue growth factor and nephrin in podocytes.

    PubMed

    Abou Msallem, J; Chalhoub, H; Al-Hariri, M; Saad, L; Jaffa, M A; Ziyadeh, F N; Jaffa, A A

    2015-12-01

    Diabetic nephropathy (DN) is the main cause of morbidity and mortality in diabetes and is characterized by mesangial matrix deposition and podocytopathy, including podocyte loss. The risk factors and mechanisms involved in the pathogenesis of DN are still not completely defined. In the present study, we aimed to understand the cellular mechanisms through which activation of B2 kinin receptors contribute to the initiation and progression of DN. Stimulation of cultured rat podocytes with bradykinin (BK) resulted in a significant increase in ROS generation, and this was associated with a significant increase in NADPH oxidase (NOX)1 and NOX4 protein and mRNA levels. BK stimulation also resulted in a signicant increase in the phosphorylation of ERK1/2 and Akt, and this effect was inhibited in the presence of NOX1 and Nox4 small interfering (si)RNA. Furthermore, podocytes stimulated with BK resulted in a significant increase in protein and mRNA levels of connective tissue growth factor (CTGF) and, at the same time, a significant decrease in protein and mRNA levels of nephrin. siRNA targeted against NOX1 and NOX4 significantly inhibited the BK-induced increase in CTGF. Nephrin expression was increased in response to BK in the presence of NOX1 and NOX4 siRNA, thus implicating a role for NOXs in modulating the BK response in podocytes. Moreover, nephrin expression in response to BK was also significantly increased in the presence of siRNA targeted against CTGF. These findings provide novel aspects of BK signal transduction pathways in pathogenesis of DN and identify novel targets for interventional strategies.

  10. Exudation of plasma and production of thromboxane in human bronchi after local bradykinin challenge.

    PubMed

    Arvidsson, P; Löfdahl, C G; Skoogh, B E; Lötvall, J

    2001-05-01

    Plasma exudation has been suggested to be an important component of the inflammatory response in asthma. Bradykinin elicits many of the features of asthma, including bronchoconstriction, cough, plasma exudation and mucus secretion. In an attempt to quantify local plasma exudation, we have employed a novel low-trauma technique with the aim of challenging and lavaging a central part of the bronchial tree, by selecting a medium sized bronchus. A fibreoptic bronchoscopy was performed in non-smoking healthy volunteers. The instrument was placed proximally in the right upper lobe bronchus. A plastic catheter, equipped with an inflatable latex balloon, was inflated with air (2-4 cmH2O). A solution (100 microl of either two different concentrations of bradykinin: 0.09 and 0.9 mg ml(-1) or normal saline) was instilled through the catheter and distal to the balloon. Eight minutes later a lavage procedure with 10 ml of saline was performed through the catheter. The procedure was then repeated twice, with the other solutions, but from the lingular and middle lobe bronchi. All solutions were given in a blinded fashion, and two different studies were performed. Lavage concentrations of albumin and IgG were quantified as measurements of plasma exudation. In our first study we found that bradykinin challenge significantly increased concentrations of albumin and IgG. In study two, there was no numeric increase in plasma proteins after local bradykinin challenge, but the concentration of thromboxane was significantly increased in lavages from bradykinin-challenged bronchi. Thus, local bronchial administration of bradykinin has the capacity to induce exudation of large plasma macromolecules into the bronchial lumen, as well as local thromboxane production.

  11. Specific immunotherapy with mugwort pollen allergoid reduce bradykinin release into the nasal fluid

    PubMed Central

    Grzanka, Alicja; Jawor, Barbara; Czecior, Eugeniusz

    2016-01-01

    Introduction A pathomechanism of allergic rhinitis is complex. A neurogenic mechanism seems to play a significant role in this phenomenon. Aim The evaluation of influence of specific immunotherapy of mugwort pollen allergic patients on the bradykinin concentration in the nasal lavage fluid. Material and methods The study included 22 seasonal allergic rhinitis patients. Thirty persons with monovalent allergy to mugwort pollen, confirmed with skin prick tests and allergen-specific immunoglobulin E, underwent a 3-year-long allergen immunotherapy with the mugwort extract (Allergovit, Allergopharma, Germany). The control group was composed of 9 persons with polyvalent sensitivity to pollen, who were treated with pharmacotherapy. Before the allergen-specific immunotherapy (AIT) and in subsequent years before the pollen seasons, a provocation allergen test with the mugwort extract was performed, together with collection of nasal fluids, where bradykinin concentration was determined according to Proud method. Results There were similar levels of bradykinin in both groups at baseline prior to therapy (AIT group: 584.0 ±87.2 vs. controls 606.3 ±106.5 pg/ml) and changes after allergen challenge 1112.4 ±334.8 vs. 1013.3 ±305.9 pg/ml as well. The bradykinin concentration in nasal lavage fluid after mugwort challenge in 1 year was lower in the AIT group (824.1 ±184.2 pg/ml vs. 1000.4 ±411.5 pg/l; p < 005) with a further significant decrease after the 2nd and 3rd year of specific immunotherapy. Significant reduction of symptoms and medications use was observed in hyposensitized patients. Conclusions A decreased level of bradykinin as a result of AIT suggests that some of the symptomatic benefits of AIT may be related to the reduced release of bradykinin into nasal secretions. These values correlate with clinical improvement within the course of treatment. PMID:27605897

  12. Bradykinin-like immunoreactive neuronal systems localized histochemically in rat brain.

    PubMed Central

    Corrêa, F M; Innis, R B; Uhl, G R; Snyder, S H

    1979-01-01

    Bradykinin-like immunoreactive structures were localized in rat brain by the indirect immunofluorescence method. Specificity of staining was demonstrated by: (i) the absence of fluorescence when preimmune serum was used, (ii) the disappearance of fluorescence when sera were preadsorbed with bradykinin, and (iii) the presence of identical staining with two different antisera. Immunoreactive neuronal cells are observed only in the hypothalamus, with especially dense clusters overlying the periventricular and dorsomedial nuclei. Fibers and varicose processes are observed in the periaqueductal gray matter, hypothalamus, perirhinal and cingulate cortices, the ventral portion of caudate-putamen, and the lateral septal area. Images PMID:375238

  13. [Treatment of drugs-associated non-hereditary angioedema mediated by bradykinin].

    PubMed

    Muller, Yannick; Harr, Thomas

    2016-01-13

    Angioedema is a deep intradermal or sub-cutaneous edema, which can be mediated by histamine, bradykinin or mixture of both components. The aims of this review are to describe the clinical approach and diagnosis of non-hereditary bradykinin-mediated angioedema induced by drugs such as: angiotensin-converting inhibitor, sartan, gliptins, rapamycin or some thrombolytic reagents and renin inhibitors. Furthermore, we will discuss the drug management of these angioedema, which is mainly based on C1 inhibitor concentrate or icatibant administration.

  14. Improvement of skin wound healing in diabetic mice by kinin B2 receptor blockade.

    PubMed

    Desposito, Dorinne; Chollet, Catherine; Taveau, Christopher; Descamps, Vincent; Alhenc-Gelas, François; Roussel, Ronan; Bouby, Nadine; Waeckel, Ludovic

    2016-01-01

    Impaired skin wound healing is a major medical problem in diabetic subjects. Kinins exert a number of vascular and other actions limiting organ damage in ischaemia or diabetes, but their role in skin injury is unknown. We investigated, through pharmacological manipulation of bradykinin B1 and B2 receptors (B1R and B2R respectively), the role of kinins in wound healing in non-diabetic and diabetic mice. Using two mouse models of diabetes (streptozotocin-induced and db/db mice) and non-diabetic mice, we assessed the effect of kinin receptor activation or inhibition by subtype-selective pharmacological agonists (B1R and B2R) and antagonist (B2R) on healing of experimental skin wounds. We also studied effects of agonists and antagonist on keratinocytes and fibroblasts in vitro. Levels of Bdkrb1 (encoding B1R) and Bdkrb2 (encoding B2R) mRNAs increased 1-2-fold in healthy and wounded diabetic skin compared with in non-diabetic skin. Diabetes delayed wound healing. The B1R agonist had no effect on wound healing. In contrast, the B2R agonist impaired wound repair in both non-diabetic and diabetic mice, inducing skin disorganization and epidermis thickening. In vitro, B2R activation unbalanced fibroblast/keratinocyte proliferation and increased keratinocyte migration. These effects were abolished by co-administration of B2R antagonist. Interestingly, in the two mouse models of diabetes, the B2R antagonist administered alone normalized wound healing. This effect was associated with the induction of Ccl2 (encoding monocyte chemoattractant protein 1)/Tnf (encoding tumour necrosis factor α) mRNAs. Thus stimulation of kinin B2 receptor impairs skin wound healing in mice. B2R activation occurs in the diabetic skin and delays wound healing. B2R blockade improves skin wound healing in diabetic mice and is a potential therapeutic approach to diabetic ulcers.

  15. Genistein prevents calcium mobilization evoked by platelet-derived growth factor without affecting calcium release by cadmium or bradykinin

    SciTech Connect

    Rong-Ming Lyu; Barnes, S.; Smith, J.B. )

    1991-03-11

    Cadmium (Cd) strikingly increases ({sup 3}H)inositol trisphosphate and evokes a spike in cytosolic free Ca (Ca{sub i}) in human dermal fibroblasts as described previously. Cd apparently activates a membrane receptor by binding to a zinc site in its external domain. Two classes of receptors are known to induce inositol phosphate formation and release stored Ca: those that are coupled to phospholipase C via GTP-binding proteins, e.g., the bradykinin (BK) receptor; and those that are tyrosine kinases, e.g. the receptor for platelet-derived growth factor (PDGF). Cd, 100 nM BK, and 10 ng/ml PDGF increased Ca{sub i} from 142 {plus minus} 24 nM to 809 {plus minus} 36, 964 {plus minus} 74, and 401 {plus minus} 52 nM (n = 5), respectively. Cd and BK immediately increased Ca{sub i}, however, there was a lag between the addition of PDGF compared to 15 {plus minus} 1 sec for Cd and 9 {plus minus} 1 sec for BK (all n = 10). Genistein (40 {mu}M, 40 min), which selectively inhibits tyrosine kinases, had no significant effect on the Ca{sub i} spike evoked by Cd or BK. In the presence of genistein Cd and BK increased Ca{sub i} from 165 {plus minus} 14 nM to 726 {plus minus} 23 and 876 {plus minus} 31 nM (n = 4), respectively. In contrast to Cd and BK, PDGF only slightly increased Ca{sub i} in the presence of 40 {mu}M genistein. The concentration of genistein that inhibited the Ca{sub i} response to PDGF by 50% was 8 {mu}M. These findings suggest that the Cd triggers a G protein-coupled receptor rather than a tyrosine kinase.

  16. Hypotensive effects of hemopressin and bradykinin in rabbits, rats and mice. A comparative study.

    PubMed

    Blais, Paul-André; Côté, Jérôme; Morin, Josée; Larouche, Annie; Gendron, Gabrielle; Fortier, Audrey; Regoli, Domenico; Neugebauer, Witold; Gobeil, Fernand

    2005-08-01

    Hemopressin is a novel vasoactive nonapeptide derived from hemoglobin's alpha-chain as recently reported by Rioli et al. [Rioli V, Gozzo FC, Heimann AS, Linardi A, Krieger JE, Shida CS, et al. Novel natural peptide substrates for endopeptidase 24.15, neurolysin, and angiotensin-converting enzyme. J Biol Chem 2003;278(10):8547-55]. In anesthetized male Wistar rats, this peptide exhibited hypotensive actions similar to those of bradykinin (BK) when administered intravenously (i.v.), and was found to be metabolized both in vitro and in vivo by several peptidases, including the angiotensin-converting enzyme (ACE). In this study, these findings were expanded upon by examining: (i) the degradation kinetics following incubation with ACE purified from rabbit lung and (ii) the blood pressure lowering effects of HP and BK injected i.v. or intra-arterially (i.a.) in male rabbits, rats, and mice. Our findings demonstrate that, in vitro, HP and BK are both degraded by ACE, but at different velocity rates. Furthermore, both HP and BK induced transient hypotension in all animals tested, although the responses to HP relative to the administration sites were significantly lower (by 10-100-fold) on an equimolar basis compared to those of BK. In rabbits, the decrease of blood pressure induced by HP (10-100 nmol/kg) did not differ whether it was administered i.v. or i.a., suggesting an absence of pulmonary/cardiac inactivation in contrast to BK (0.1-1 nmol/kg). The in vivo effect of HP was significantly potentiated in rabbits immunostimulated with bacterial lipopolysaccharide (LPS), but was unaffected by both the B2 receptor antagonist HOE 140 (0.1 micromol/kg) and captopril (100 microg/kg), contrary to BK. Therefore, HP acts as a weak hypotensive mediator, which does not activate kinin B2 receptors, but uses a functional site and/or signaling paths appearing to be up-regulated by LPS.

  17. 18 CFR 1b.1 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

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  18. 18 CFR 1b.1 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

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  19. 18 CFR 1b.1 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Definitions. 1b.1 Section 1b.1 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.1 Definitions. For purposes of this part—...

  20. 18 CFR 1b.1 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Definitions. 1b.1 Section 1b.1 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.1 Definitions. For purposes of this part—...

  1. 18 CFR 1b.1 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

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  2. 45 CFR 5b.1 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Definitions. 5b.1 Section 5b.1 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION PRIVACY ACT REGULATIONS § 5b.1 Definitions. As used in this part: (a) Access means availability of a record to a subject individual. (b) Agency means the Department of Health and...

  3. 34 CFR 5b.1 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

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  4. Plexin B1 inhibits MET through direct association and regulates Shp2 expression in melanocytes.

    PubMed

    Soong, Joanne; Scott, Glynis

    2013-01-15

    Plexin B1, the receptor for Semaphorin 4D (Sema4D), is expressed by melanocytes in the skin. We recently showed that Sema4D suppresses activation of the hepatocyte growth factor receptor, MET, in melanocytes, and that knockdown of Plexin B1 results in activation of MET. MET signaling mediates proliferation, survival and migration in melanocytes, and its activation is associated with transformation of melanocytes to melanoma. In this report we investigated the mechanism by which Plexin B1 inhibits MET activation. Our results show that Plexin B1 and MET exist as an oligomeric receptor-receptor complex in melanocytes, and that receptor association is increased by Sema4D. MET and Plexin B1 receptor complexes were identified along the cell body of melanocytes, and Sema4D increased receptor association on dendrites, suggesting that Sema4D regulates MET-dependent processes at precise locations on the melanocyte. Despite activation of MET, Plexin B1 knockdowns proliferated slowly and showed increased apoptosis compared with controls. Shp2, a non-receptor protein tyrosine phosphatase, translates growth and survival signals from MET and other receptor tyrosine kinases. Plexin B1 knockdowns had markedly lower levels of Shp2 compared with controls, and Sema4D upregulated Shp2 expression at the protein and message level in normal melanocytes. Functional studies showed that blockade of Shp2 activity abrogated MET-dependent activation of Erk1/Erk2 and Akt in melanocytes. These results suggest a complex role for Sema4D and Plexin B1 in orchestrating signaling from the MET receptor in melanocytes. Because Shp2 is a downstream adaptor protein for multiple receptors, Sema4D may control the effects of several growth factors on melanocytes through regulation of Shp2.

  5. Stimulation of phosphatidylinositol hydrolysis, protein kinase C translocation, and mitogen-activated protein kinase activity by bradykinin in rat ventricular myocytes: dissociation from the hypertrophic response.

    PubMed Central

    Clerk, A; Gillespie-Brown, J; Fuller, S J; Sugden, P H

    1996-01-01

    In ventricular myocytes cultured from neonatal rat hearts, bradykinin (BK), kallidin or BK(1-8) [(Des-Arg9)BK] stimulated PtdinsP2 hydrolysis by 3-4-fold. EC50 values were 6 nM (BK), 2 nM (kallidin), and 14 microM [BK(1-8)]. BK or kallidin stimulated the rapid (less than 30 s) translocation of more than 80% of the novel protein kinase C (PKC) isoforms nPKC-delta and nPKC-epsilon from the soluble to the particulate fraction. EC50 values for nPKC-delta translocation by BK or kallidin were 10 and 2 nM respectively. EC50 values for nPKC-epsilon translocation by BK or kallidin were 2 and 0.6 nM respectively. EC50 values for the translocation of nPKC-delta and nPKC-epsilon by BK(1-8) were more than 5 microM. The classical PKC, cPKC-alpha, and the atypical PKC, nPKC-zeta, did not translocate. BK caused activation and phosphorylation of p42-mitogen-activated protein kinase (MAPK) (maximal at 3-5 min, 30-35% of p42-MAPK phosphorylated). p44-MAPK was similarly activated. EC50 values for p42/p44-MAPK activation by BK were less than 1 nM whereas values for BK(1-8) were more than 10 microM. The order of potency [BK approximately equal to kallidin >> BK (1-8)] for the stimulation of PtdInsP2 hydrolysis, nPKC-delta and nPKC-epsilon translocation, and p42/p44-MAPK activities suggests involvement of the B2 BK receptor subtype. In addition, stimulation of all three processes by BK was inhibited by the B2BK receptor-selective antagonist HOE140 but not by the B1-selective antagonist Leu8BK(1-8). Exposure of cells to phorbol 12-myristate 13-acetate for 24 h inhibited subsequent activation of p42/p44-MAPK by BK suggesting participation of nPKC (and possibly cPKC) isoforms in the activation process. Thus, like hypertrophic agents such as endothelin-1 (ET-1) and phenylephrine (PE), BK activates PtdInsP2 hydrolysis, translocates nPKC-delta, and nPKC-epsilon, and activates p42/p44-MAPK. However, in comparison with ET-1 and PE, BK was only weakly hypertrophic as assessed by cell morphology

  6. Suppression of Lipid Accumulation by Indole-3-Carbinol Is Associated with Increased Expression of the Aryl Hydrocarbon Receptor and CYP1B1 Proteins in Adipocytes and with Decreased Adipocyte-Stimulated Endothelial Tube Formation

    PubMed Central

    Wang, Mei-Lin; Lin, Shyh-Hsiang; Hou, Yuan-Yu; Chen, Yue-Hwa

    2016-01-01

    This study investigated the effects of indole-3-carbinol (I3C) on adipogenesis- and angiogenesis-associated factors in mature adipocytes. The cross-talk between mature adipocytes and endothelial cells (ECs) was also explored by cultivating ECs in a conditioned medium (CM) by using I3C-treated adipocytes. The results revealed that I3C significantly inhibited triglyceride accumulation in mature adipocytes in association with significantly increased expression of AhR and CYP1B1 proteins as well as slightly decreased nuclear factor erythroid-derived factor 2–related factor 2, hormone-sensitive lipase, and glycerol-3-phosphate dehydrogenase expression by mature adipocytes. Furthermore, I3C inhibited CM-stimulated endothelial tube formation, which was accompanied by the modulated secretion of angiogenic factors in adipocytes, including vascular endothelial growth factor, interleukin-6, matrix metalloproteinases, and nitric oxide. In conclusion, I3C reduced lipid droplet accumulation in adipocytes and suppressed adipocyte-stimulated angiogenesis in ECs, suggesting that I3C is a potential therapeutic agent for treating obesity and obesity-associated disorders. PMID:27527145

  7. Bradykinin-stimulated calcium influx in cultured bovine aortic endothelial cells

    SciTech Connect

    Schilling, W.P.; Ritchie, A.K.; Navarro, L.T.; Eskin, S.G. Univ. of Texas Medical Branch, Galveston )

    1988-08-01

    Bradykinin (BK)-stimulated release of endothelium-derived relaxing factor has been linked to a rise in cytosolic Ca{sup 2+} concentration and a change of K{sup +} permeability of the endothelial cell. In the present study, measurement of BK-induced changes in fura-2 fluorescence and {sup 86}Rb{sup +} efflux were used to monitor changes in cytosolic Ca{sup 2+} and K{sup +} permeability in cultured bovine aortic endothelial cells. In the presence of normal extracellular Ca{sup 2+}, BK induced a fourfold increase in cytosolic Ca{sup 2+}, which peaked at 20 s and declined within 1 min to a value that was 50% of the peak level. Subsequently, cytosolic Ca{sup 2+} decreased and approached basal levels within 8 min. In the absence of Ca{sup 2+}, BK produced a 1.5- to 2-fold increase in cytosolic Ca{sup 2+} that peaked within 20 s and declined to basal levels within 2 min. Addition of Ca{sup 2+} to the Ca-free reaction buffer 3-5 min after addition of BK resulted in a two-to three-fold increase in cytosolic Ca{sup 2+} that declined slowly back to basal levels. Thus Ca{sup 2+} influx can occur in response to BK at a time when there is minimal elevation of cytosolic Ca{sup 2+} above the resting level. Under all conditions tested, {sup 86}Rb{sup +} efflux paralleled changes in the cytosolic Ca{sup 2+}, suggesting that efflux occurred through Ca{sup 2+}-activated K{sup +} channels. Isosmotic substitution of Na{sup +} with N-methyl-D-glucamine did not affect the BK-stimulated changes in cytosolic Ca{sup 2+} or {sup 86}Rb{sup +} efflux, suggesting that Na{sup +}-Ca{sup 2+} exchange plays little role in the BK response. These results suggest that BK stimulates Ca{sup 2+} influx via a BK receptor-operated channel or a channel activated by some internal messenger other than Ca{sup 2+}.

  8. Contribution of TRPV1 to the bradykinin-evoked nociceptive behavior and excitation of cutaneous sensory neurons.

    PubMed

    Katanosaka, Kimiaki; Banik, Ratan Kumar; Giron, Rocio; Higashi, Tomohiro; Tominaga, Makoto; Mizumura, Kazue

    2008-11-01

    Bradykinin (BK), a major inflammatory mediator, excites and sensitizes nociceptor neurons/fibers, thus evoking pain and hyperalgesia. The cellular signaling mechanisms underlying these actions have remained unsolved, especially in regard to the identity of channels that mediate acute excitation. Here, to clarify the contribution of transient receptor potential vanilloid 1 (TRPV1), a heat-sensitive ion channel, to the BK-evoked nociceptor excitation and pain, we examined the behavioral and physiological BK-responses in TRPV1-deficient (KO) mice. A nocifencive behavior after BK injection (100 pmol/site) into mouse sole was reduced in TRPV1-KO mice compared with wild-type (WT). A higher dose of BK (1 nmol/site), however, induced the response in TRPV1-KO mice indistinguishable from that in the WT. BK-evoked excitation of cutaneous C-fibers in TRPV1-KO mice was comparable to that in WT. BK clearly increased intracellular calcium in cultured dorsal root ganglion (DRG) neurons of TRPV1-KO mice, although the incidence of BK-sensitive neurons was reduced. BK has been reported to activate TRPA1 indirectly, yet a considerable part of BK-sensitive DRG neurons did not respond to a TRPA1 agonist, mustard oil. These results suggest that BK-evoked nociception/nociceptor response would not be simply explained by activation of TRPV1 and A1, and that BK-evoked nociceptor excitation would be mediated by several ionic mechanisms.

  9. Bradykinin activates ADP-ribosyl cyclase in neuroblastoma cells: intracellular concentration decrease in NAD and increase in cyclic ADP-ribose.

    PubMed

    Higashida, Haruhiro; Salmina, Alla; Hashii, Minako; Yokoyama, Shigeru; Zhang, Jia-Sheng; Noda, Mami; Zhong, Zen-Guo; Jin, Duo

    2006-09-04

    ADP-ribosyl cyclase activity in the crude membrane fraction of neuroblastomaxglioma NGPM1-27 hybrid cells was measured by monitoring [(3)H] cyclic ADP-ribose (cADPR) formation from [(3)H] NAD(+). Bradykinin (BK) at 100nM increased ADP-ribosyl cyclase activity by about 2.5-fold. Application of 300nM BK to living NGPM1-27 cells decreased NAD(+) to 78% of the prestimulation level at 30s. In contrast, intracellular cADPR concentrations were increased by 2-3-fold during the period from 30 to 120s after the same treatment. Our results suggest that cADPR is one of the second messengers downstream of B(2) BK receptors.

  10. Iodination of (Tyr8)-bradykinin-comparison of chloramine-T and lactoperoxidase techniques

    SciTech Connect

    Redman, L.W.; Tustanoff, E.R.

    1984-01-01

    Antigen-antibody kinetics were studied using a hapten which was iodinated by two unique procedures. Using bradykinin, a vasopressor hormone as a model peptide, radioactive iodination (/sup 125/I) of its 8-tyrosyl analogue was carried out both enzymatically and chemically using modified procedures. Two distinct chemical species were obtained which were characterized on a chromatographic, chemical as well as charge basis as a mono-iodinated form of (Tyr8)-bradykinin using the lactoperoxidase procedure and a di-iodinated entity using chloramine-T technique. The addition of a second iodine atom to the antigen lowers its immunoreactivity for its antibody and thus alters the kinetics of this reaction. Further experiments on the stability (temperature, time of storage, and chemical environment) of these iodinated peptides are described.

  11. Neuronal SH2B1 is essential for controlling energy and glucose homeostasis.

    PubMed

    Ren, Decheng; Zhou, Yingjiang; Morris, David; Li, Minghua; Li, Zhiqin; Rui, Liangyou

    2007-02-01

    SH2B1 (previously named SH2-B), a cytoplasmic adaptor protein, binds via its Src homology 2 (SH2) domain to a variety of protein tyrosine kinases, including JAK2 and the insulin receptor. SH2B1-deficient mice are obese and diabetic. Here we demonstrated that multiple isoforms of SH2B1 (alpha, beta, gamma, and/or delta) were expressed in numerous tissues, including the brain, hypothalamus, liver, muscle, adipose tissue, heart, and pancreas. Rat SH2B1beta was specifically expressed in neural tissue in SH2B1-transgenic (SH2B1(Tg)) mice. SH2B1(Tg) mice were crossed with SH2B1-knockout (SH2B1(KO)) mice to generate SH2B1(TgKO) mice expressing SH2B1 only in neural tissue but not in other tissues. Systemic deletion of the SH2B1 gene resulted in metabolic disorders in SH2B1(KO) mice, including hyperlipidemia, leptin resistance, hyperphagia, obesity, hyperglycemia, insulin resistance, and glucose intolerance. Neuron-specific restoration of SH2B1beta not only corrected the metabolic disorders in SH2B1(TgKO) mice, but also improved JAK2-mediated leptin signaling and leptin regulation of orexigenic neuropeptide expression in the hypothalamus. Moreover, neuron-specific overexpression of SH2B1 dose-dependently protected against high-fat diet-induced leptin resistance and obesity. These observations suggest that neuronal SH2B1 regulates energy balance, body weight, peripheral insulin sensitivity, and glucose homeostasis at least in part by enhancing hypothalamic leptin sensitivity.

  12. Pulmonary oedema producing toxin from Mesobuthus tamulus venom augments cardio-respiratory reflexes through B2 kinin receptors.

    PubMed

    Alex, Anitha B; Akella, Aparna; Tiwari, Anil K; Deshpande, Shripad B

    2014-01-01

    The current study was undertaken to compare the effects of pulmonary oedema producing toxin (PO-Tx) isolated from Mesobuthus tamulus venom on cardio-respiratory reflexes with exogenously administered bradykinin (BK) and to delineate the type of BK receptors mediating these responses. Jugular venous injection of phenyldiguanide (PDG) in anaesthetized rats produced reflex bradycardia, hypotension and apnoea. The PDG-induced reflex was augmented (two folds) by PO-Tx. The pulmonary water content in PO-Tx treated group was also increased. The PO-Tx-induced reflex changes as well as pulmonary oedema were blocked by-Hoe-140 implicating the involvement of B2 kinin receptors. Exogenous BK also produced augmentation (two folds) of the PDG-induced reflexes and increased the pulmonary water content. The BK-induced augmentation was blocked by pre-treatment with des-Arg10 Hoe 140 (a B1 receptor antagonist) and Hoe 140 (B2 receptor antagonist). However, these antagonists did not prevent the development of BK-induced pulmonary oedema. Present results indicate that PO-Tx augmented the PDG-induced reflex responses similar to BK and the PO-Tx induced augmentation of reflexes is mediated through B2 receptors.

  13. Differential regulation of collagen secretion by kinin receptors in cardiac fibroblast and myofibroblast

    SciTech Connect

    Catalán, Mabel; Smolic, Christian; Contreras, Ariel; Ayala, Pedro; Olmedo, Ivonne; Copaja, Miguel; Boza, Pía; Vivar, Raúl; Avalos, Yennifer; Lavandero, Sergio; Velarde, Victoria; Díaz-Araya, Guillermo

    2012-06-15

    Kinins mediate their cellular effects through B1 (B1R) and B2 (B2R) receptors, and the activation of B2R reduces collagen synthesis in cardiac fibroblasts (CF). However, the question of whether B1R and/or B2R have a role in cardiac myofibroblasts remains unanswered. Methods: CF were isolated from neonate rats and myofibroblasts were generated by an 84 h treatment with TGF-β1 (CMF). B1R was evaluated by western blot, immunocytochemistry and radioligand assay; B2R, inducible nitric oxide synthase (iNOS), endothelial nitric oxide synthase (eNOS), and cyclooxygenases 1and 2 (COX-1, and COX-2) were evaluated by western blot; intracellular Ca{sup +2} levels were evaluated with Fluo-4AM; collagen secretion was measured in the culture media using the picrosirius red assay kit. Results: B2R, iNOS, COX-1 and low levels of B1R but not eNOS, were detected by western blot in CF. Also, B1R, B2R, and COX-2 but not iNOS, eNOS or COX-1, were detected by western blot in CMF. By immunocytochemistry, our results showed lower intracellular B1R levels in CF and higher B1R levels in CMF, mainly localized on the cell membrane. Additionally, we found B1R only in CMF cellular membrane through radioligand displacement assay. Bradykinin (BK) B2R agonist increased intracellular Ca{sup 2+} levels and reduced collagen secretion both in CF and CMF. These effects were blocked by HOE-140, and inhibited by L-NAME, 1400W and indomethacin. Des-Arg-kallidin (DAKD) B1R agonist did not increase intracellular Ca{sup 2+} levels in CF; however, after preincubation for 1 h with DAKD and re-stimulation with the same agonist, we found a low increase in intracellular Ca{sup 2+} levels. Finally, DAKD increased intracellular Ca{sup 2+} levels and decreased collagen secretion in CMF, being this effect blocked by the B1R antagonist des-Arg9-Leu8-kallidin and indomethacin, but not by L-NAME or 1400 W. Conclusion: B1R, B2R, iNOS and COX-1 were expressed differently between CF and CMF, and collagen secretion was

  14. Procollagen C-endopeptidase Enhancer Protein 2 (PCPE2) Reduces Atherosclerosis in Mice by Enhancing Scavenger Receptor Class B1 (SR-BI)-mediated High-density Lipoprotein (HDL)-Cholesteryl Ester Uptake.

    PubMed

    Pollard, Ricquita D; Blesso, Christopher N; Zabalawi, Manal; Fulp, Brian; Gerelus, Mark; Zhu, Xuewei; Lyons, Erica W; Nuradin, Nebil; Francone, Omar L; Li, Xiang-An; Sahoo, Daisy; Thomas, Michael J; Sorci-Thomas, Mary G

    2015-06-19

    Studies in human populations have shown a significant correlation between procollagen C-endopeptidase enhancer protein 2 (PCPE2) single nucleotide polymorphisms and plasma HDL cholesterol concentrations. PCPE2, a 52-kDa glycoprotein located in the extracellular matrix, enhances the cleavage of C-terminal procollagen by bone morphogenetic protein 1 (BMP1). Our studies here focused on investigating the basis for the elevated concentration of enlarged plasma HDL in PCPE2-deficient mice to determine whether they protected against diet-induced atherosclerosis. PCPE2-deficient mice were crossed with LDL receptor-deficient mice to obtain LDLr(-/-), PCPE2(-/-) mice, which had elevated HDL levels compared with LDLr(-/-) mice with similar LDL concentrations. We found that LDLr(-/-), PCPE2(-/-) mice had significantly more neutral lipid and CD68+ infiltration in the aortic root than LDLr(-/-) mice. Surprisingly, in light of their elevated HDL levels, the extent of aortic lipid deposition in LDLr(-/-), PCPE2(-/-) mice was similar to that reported for LDLr(-/-), apoA-I(-/-) mice, which lack any apoA-I/HDL. Furthermore, LDLr(-/-), PCPE2(-/-) mice had reduced HDL apoA-I fractional clearance and macrophage to fecal reverse cholesterol transport rates compared with LDLr(-/-) mice, despite a 2-fold increase in liver SR-BI expression. PCPE2 was shown to enhance SR-BI function by increasing the rate of HDL-associated cholesteryl ester uptake, possibly by optimizing SR-BI localization and/or conformation. We conclude that PCPE2 is atheroprotective and an important component of the reverse cholesterol transport HDL system.

  15. 18 CFR 3b.1 - Purpose.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Purpose. 3b.1 Section 3b.1 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES COLLECTION, MAINTENANCE, USE, AND DISSEMINATION OF RECORDS OF IDENTIFIABLE...

  16. 45 CFR 73b.1 - Scope.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... the Public Health Service, because of violation of the post-employment restrictions of the conflict of... 45 Public Welfare 1 2010-10-01 2010-10-01 false Scope. 73b.1 Section 73b.1 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION DEBARMENT OR SUSPENSION OF FORMER...

  17. 45 CFR 73b.1 - Scope.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... the Public Health Service, because of violation of the post-employment restrictions of the conflict of... 45 Public Welfare 1 2012-10-01 2012-10-01 false Scope. 73b.1 Section 73b.1 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION DEBARMENT OR SUSPENSION OF FORMER...

  18. B-1 cells temper endotoxemic inflammatory responses.

    PubMed

    Barbeiro, Denise Frediani; Barbeiro, Hermes Vieira; Faintuch, Joel; Ariga, Suely K Kubo; Mariano, Mario; Popi, Ana Flávia; de Souza, Heraldo Possolo; Velasco, Irineu Tadeu; Soriano, Francisco Garcia

    2011-03-01

    Sepsis syndrome is caused by inappropriate immune activation due to bacteria and bacterial components released during infection. This syndrome is the leading cause of death in intensive care units. Specialized B-lymphocytes located in the peritoneal and pleural cavities are known as B-1 cells. These cells produce IgM and IL-10, both of which are potent regulators of cell-mediated immunity. It has been suggested that B-1 cells modulate the systemic inflammatory response in sepsis. In this study, we conducted in vitro and in vivo experiments in order to investigate a putative role of B-1 cells in a murine model of LPS-induced sepsis. Macrophages and B-1 cells were studied in monocultures and in co-cultures. The B-1 cells produced the anti-inflammatory cytokine IL-10 in response to LPS. In the B-1 cell-macrophage co-cultures, production of proinflammatory mediators (TNF-α, IL-6 and nitrite) was lower than in the macrophage monocultures, whereas that of IL-10 was higher in the co-cultures. Co-culture of B-1 IL-10(-/-) cells and macrophages did not reduce the production of the proinflammatory mediators (TNF-α, IL-6 and nitrite). After LPS injection, the mortality rate was higher among Balb/Xid mice, which are B-1 cell deficient, than among wild-type mice (65.0% vs. 0.0%). The Balb/Xid mice also presented a proinflammatory profile of TNF-α, IL-6 and nitrite, as well as lower levels of IL-10. In the early phase of LPS stimulation, B-1 cells modulate the macrophage inflammatory response, and the main molecular pathway of that modulation is based on IL-10-mediated intracellular signaling.

  19. Rhythmic control of activity and sleep by class B1 GPCRs

    PubMed Central

    Kunst, Michael; Tso, Matthew C.F.; Ghosh, D. Dipon; Herzog, Erik D.; Nitabach, Michael N.

    2015-01-01

    Members of the class B1 family of G-protein coupled receptors (GPCRs) whose ligands are neuropeptides have been implicated in regulation of circadian rhythms and sleep in diverse metazoan clades. This review discusses the cellular and molecular mechanisms by which class B1 GPCRs, especially the mammalian VPAC2 receptor and its functional homologue PDFR in Drosophila and C. elegans, regulate arousal and daily rhythms of sleep and wake. There are remarkable parallels in the cellular and molecular roles played by class B1 intercellular signaling pathways in coordinating arousal and circadian timekeeping across multiple cells and tissues in these very different genetic model organisms. PMID:25410535

  20. Observation of B Meson decays to b1pi and b1K.

    PubMed

    Aubert, B; Bona, M; Boutigny, D; Karyotakis, Y; Lees, J P; Poireau, V; Prudent, X; Tisserand, V; Zghiche, A; Tico, J Garra; Grauges, E; Lopez, L; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Pegna, D Lopes; Lynch, G; Mir, L M; Orimoto, T J; Osipenkov, I L; Ronan, M T; Tackmann, K; Tanabe, T; Wenzel, W A; Del Amo Sanchez, P; Hawkes, C M; Watson, A T; Held, T; Koch, H; Pelizaeus, M; Schroeder, T; Steinke, M; Walker, D; Asgeirsson, D J; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Barrett, M; Khan, A; Saleem, M; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Liu, F; Long, O; Shen, B C; Zhang, L; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Schalk, T; Schumm, B A; Seiden, A; Wilson, M G; Winstrom, L O; Chen, E; Cheng, C H; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Gabareen, A M; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Klose, V; Kobel, M J; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Lombardo, V; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Watson, J E; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Santoro, V; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Dauncey, P D; Flack, R L; Nash, J A; Vazquez, W Panduro; Tibbetts, M; Behera, P K; Chai, X; Charles, M J; Mallik, U; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Lae, C K; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Béquilleux, J; D'Orazio, A; Davier, M; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wang, W F; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; George, K A; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Paramesvaran, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Salvati, E; Saremi, S; Cowan, R; Dujmic, D; Fisher, P H; Koeneke, K; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Zhao, M; Zheng, Y; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; De Nardo, G; Fabozzi, F; Lista, L; Monorchio, D; Sciacca, C; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; Losecco, J M; Benelli, G; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gagliardi, N; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Ben-Haim, E; Briand, H; Calderini, G; Chauveau, J; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; Leruste, Ph; Malclès, J; Ocariz, J; Perez, A; Prendki, J; Gladney, L; Biasini, M; Covarelli, R; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Carpinelli, M; Cenci, R; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Mazur, M A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Haire, M; Biesiada, J; Elmer, P; Lau, Y P; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Baracchini, E; Bellini, F; Cavoto, G; Del Re, D; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Gioi, L Li; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Castelli, G; Franek, B; Olaiya, E O; Ricciardi, S; Roethel, W; Wilson, F F; Emery, S; Escalier, M; Gaidot, A; Ganzhur, S F; de Monchenault, G Hamel; Kozanecki, W; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Berger, N; Claus, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Glanzman, T; Gowdy, S J; Graham, M T; Grenier, P; Hast, C; Hryn'ova, T; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Luitz, S; Luth, V; Lynch, H L; Macfarlane, D B; Marsiske, H; Messner, R; Muller, D R; O'Grady, C P; Ofte, I; Perazzo, A; Perl, M; Pulliam, T; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Stelzer, J; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; van Bakel, N; Wagner, A P; Weaver, M; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Yi, K; Young, C C; Burchat, P R; Edwards, A J; Majewski, S A; Petersen, B A; Wilden, L; Ahmed, S; Alam, M S; Bula, R; Ernst, J A; Jain, V; Pan, B; Saeed, M A; Wappler, F R; Zain, S B; Krishnamurthy, M; Spanier, S M; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Izen, J M; Lou, X C; Ye, S; Bianchi, F; Gallo, F; Gamba, D; Pelliccioni, M; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, Sw; Bhuyan, B; Hamano, K; Kowalewski, R; Nugent, I M; Roney, J M; Sobie, R J; Harrison, P F; Ilic, J; Latham, T E; Mohanty, G B; Band, H R; Chen, X; Dasu, S; Flood, K T; Hollar, J J; Kutter, P E; Pan, Y; Pierini, M; Prepost, R; Wu, S L; Neal, H

    2007-12-14

    We present the results of searches for decays of B mesons to final states with a b1 meson and a charged pion or kaon. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 382x10(6) BB[over ] pairs produced in e+e- annihilation. The results for the branching fractions are, in units of 10(-6), B(B+-->b1(0)pi+)=6.7+/-1.7+/-1.0, B(B+-->b1(0)K+)=9.1+/-1.7+/-1.0, B(B0-->b1(-/+)pi(+/-))=10.9+/-1.2+/-0.9, and B(B0-->b1(-)K+)=7.4+/-1.0+/-1.0, with the assumption that B(b1-->omega pi)=1. We also measure charge and flavor asymmetries A(ch)(B+-->b1(0)pi+)=0.05+/-0.16+/-0.02, Ach(B+-->b1(0)K+)=-0.46+/-0.20+/-0.02, A(ch)(B0-->b1(-/+)pi(+/-))=-0.05+/-0.10+/-0.02, C(B0-->b1(-/+)pi(+/-))=-0.22+/-0.23+/-0.05, DeltaC(B0-->b1(-/+)pi(+/-))=-1.04+/-0.23+/-0.08, and A(ch)(B0-->b1(-)K+)=-0.07+/-0.12+/-0.02. The first error quoted is statistical, and the second systematic.

  1. Surface densities of ephrin-B1 determine EphB1-coupled activation of cell attachment through alphavbeta3 and alpha5beta1 integrins.

    PubMed Central

    Huynh-Do, U; Stein, E; Lane, A A; Liu, H; Cerretti, D P; Daniel, T O

    1999-01-01

    Receptors of the Eph family and their ligands (ephrins) mediate developmental vascular assembly and direct axonal guidance. Migrating cell processes identify appropriate targets within migratory fields based on topographically displayed ephrin gradients. Here, EphB1 regulated cell attachment by discriminating the density at which ephrin-B1 was displayed on a reconstituted surface. EphB1-ephrin-B1 engagement did not promote cell attachment through mechanical tethering, but did activate integrin-mediated attachment. In endothelial cells, attachment to RGD peptides or fibrinogen was mediated through alphavbeta3 integrin. EphB1 transfection conferred ephrin-B1-responsive activation of alpha5beta1 integrin-mediated cell attachment in human embryonic kidney cells. Activation-competent but signaling-defective EphB1 point mutants failed to stimulate ephrin-B1 dependent attachment. These findings lead us to propose that EphB1 functions as a 'ligand density sensor' to signal integrin-mediated cell-matrix attachment. PMID:10205170

  2. The double life of a B-1 cell: self-reactivity selects for protective effector functions.

    PubMed

    Baumgarth, Nicole

    2011-01-01

    During their development, B and T cells with self-reactive antigen receptors are generally deleted from the repertoire to avoid autoimmune diseases. Paradoxically, innate-like B-1 cells in mice are positively selected for self-reactivity and form a pool of long-lived, self-renewing B cells that produce most of the circulating natural IgM antibodies. This Review provides an overview of the developmental processes that shape the B-1 cell pool in mice, outlines the functions of B-1 cells in both the steady state and during host defence, and discusses possible functional B-1 cell homologues that exist in humans.

  3. SH2B1 and IRSp53 proteins promote the formation of dendrites and dendritic branches.

    PubMed

    Chen, Chien-Jen; Shih, Chien-Hung; Chang, Yu-Jung; Hong, Shao-Jing; Li, Tian-Neng; Wang, Lily Hui-Ching; Chen, Linyi

    2015-03-06

    SH2B1 is an adaptor protein known to enhance neurite outgrowth. In this study, we provide evidence suggesting that the SH2B1 level is increased during in vitro culture of hippocampal neurons, and the β isoform (SH2B1β) is the predominant isoform. The fact that formation of filopodia is prerequisite for neurite initiation suggests that SH2B1 may regulate filopodium formation and thus neurite initiation. To investigate whether SH2B1 may regulate filopodium formation, the effect of SH2B1 and a membrane and actin regulator, IRSp53 (insulin receptor tyrosine kinase substrate p53), is investigated. Overexpressing both SH2B1β and IRSp53 significantly enhances filopodium formation, neurite outgrowth, and branching. Both in vivo and in vitro data show that SH2B1 interacts with IRSp53 in hippocampal neurons. This interaction depends on the N-terminal proline-rich domains of SH2B1. In addition, SH2B1 and IRSp53 co-localize at the plasma membrane, and their levels increase in the Triton X-100-insoluble fraction of developing neurons. These findings suggest that SH2B1-IRSp53 complexes promote the formation of filopodia, neurite initiation, and neuronal branching.

  4. SH2B1 and IRSp53 Proteins Promote the Formation of Dendrites and Dendritic Branches*

    PubMed Central

    Chen, Chien-Jen; Shih, Chien-Hung; Chang, Yu-Jung; Hong, Shao-Jing; Li, Tian-Neng; Wang, Lily Hui-Ching; Chen, Linyi

    2015-01-01

    SH2B1 is an adaptor protein known to enhance neurite outgrowth. In this study, we provide evidence suggesting that the SH2B1 level is increased during in vitro culture of hippocampal neurons, and the β isoform (SH2B1β) is the predominant isoform. The fact that formation of filopodia is prerequisite for neurite initiation suggests that SH2B1 may regulate filopodium formation and thus neurite initiation. To investigate whether SH2B1 may regulate filopodium formation, the effect of SH2B1 and a membrane and actin regulator, IRSp53 (insulin receptor tyrosine kinase substrate p53), is investigated. Overexpressing both SH2B1β and IRSp53 significantly enhances filopodium formation, neurite outgrowth, and branching. Both in vivo and in vitro data show that SH2B1 interacts with IRSp53 in hippocampal neurons. This interaction depends on the N-terminal proline-rich domains of SH2B1. In addition, SH2B1 and IRSp53 co-localize at the plasma membrane, and their levels increase in the Triton X-100-insoluble fraction of developing neurons. These findings suggest that SH2B1-IRSp53 complexes promote the formation of filopodia, neurite initiation, and neuronal branching. PMID:25586189

  5. Cyp1b1 exerts opposing effects on intestinal tumorigenesis via exogenous and endogenous substrates

    PubMed Central

    Halberg, Richard B.; Larsen, Michele Campaigne; Elmergreen, Tammy L.; Ko, Alex Y.; Irving, Amy A.; Clipson, Linda; Jefcoate, Colin R.

    2008-01-01

    Cytochrome P450 1B1 (Cyp1b1) metabolism contributes to physiological functions during embryogenesis, but also to carcinogenic activation of polycyclic aromatic hydrocarbons (PAH). We generated Cyp1b1-deficient mice carrying the Min allele of the Adenomatous polyposis coli gene. These Cyp1b1-deficient Min mice developed twice as many tumors as Min controls, which, however, remained similar in size and histology. Tumors from older (130 day) Cyp1b1-deficient Min mice exhibited focal areas of nuclear atypia associated with less organized epithelia. The metabolism of endogenous substrates by Cyp1b1, therefore, suppresses tumor initiation, but also affects progression. Treatment of Min mice with 7,12-dimethylbenzanthracene (DMBA) doubled both tumor multiplicity and size within 20 days, but not when mice lacked Cyp1b1. This was paralleled by an abnormal staining of crypts with β catenin, phospho-IKK, and ReIA, which may represent an early stage of tumorigenesis similar to aberrant crypt formation. Cyp1b1 deletion did not affect circulating DMBA and metabolites. Cyp1b1 expression was higher in the tumors compared to normal small intestines. Increased tumorigenesis may, therefore, arise from generation of DMBA metabolites by Cyp1b1 in the developing tumors. Benzo(a)pyrene (BP), which is similarly activated by Cyp1b1 in vitro, did not affect tumorigenesis in Min mice. By contrast, BP and DMBA each suppressed tumor multiplicity in absence of Cyp1b1. Cyp1b1 metabolism of DMBA and endogenous oxygenation products may each impact a tumor promoting NF-κB. activation, whereas Ah receptor activation by PAH effects suppression. Tumorigenesis may, therefore, depend on activation of PAH by Cyp1b1, and on off-setting suppression by Cyp1b1 of endogenous tumor-enhancing substrates. PMID:18794127

  6. Large dynamic range relative B1+ mapping

    PubMed Central

    Hess, Aaron T.; Aljabar, Paul; Malik, Shaihan J.; Jezzard, Peter; Robson, Matthew D.; Hajnal, Joseph V.; Koopmans, Peter J.

    2015-01-01

    Purpose Parallel transmission (PTx) requires knowledge of the B1+ produced by each element. However, B1+ mapping can be challenging when transmit fields exhibit large dynamic range. This study presents a method to produce high quality relative B1+ maps when this is the case. Theory and Methods The proposed technique involves the acquisition of spoiled gradient echo (SPGR) images at multiple radiofrequency drive levels for each transmitter. The images are combined using knowledge of the SPGR signal equation using maximum likelihood estimation, yielding an image for each channel whose signal is proportional to the B1+ field strength. Relative B1+ maps are then obtained by taking image ratios. The method was tested using numerical simulations, phantom imaging, and through in vivo experiments. Results The numerical simulations demonstrated that the proposed method can reconstruct relative transmit sensitivities over a wide range of B1+ amplitudes and at several SNR levels. The method was validated at 3 Tesla (T) by comparing it with an alternative B1+ mapping method, and demonstrated in vivo at 7T. Conclusion Relative B1+ mapping in the presence of large dynamic range has been demonstrated through numerical simulations, phantom imaging at 3T and experimentally at 7T. The method will enable PTx to be applied in challenging imaging scenarios at ultrahigh field. Magn Reson Med 76:490–499, 2016. © 2015 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. PMID:26308375

  7. MR fingerprinting with simultaneous B1 estimation

    PubMed Central

    Sawiak, Stephen J.

    2015-01-01

    Purpose MR fingerprinting (MRF) can be used for quantitative estimation of physical parameters in MRI. Here, we extend the method to incorporate B1 estimation. Methods The acquisition is based on steady state free precession MR fingerprinting with a Cartesian trajectory. To increase the sensitivity to the B1 profile, abrupt changes in flip angle were introduced in the sequence. Slice profile and B1 effects were included in the dictionary and the results from two‐ and three‐dimensional (3D) acquisitions were compared. Acceleration was demonstrated using retrospective undersampling in the phase encode directions of 3D data exploiting redundancy between MRF frames at the edges of k‐space. Results Without B1 estimation, T2 and B1 were inaccurate by more than 20%. Abrupt changes in flip angle improved B1 maps. T1 and T2 values obtained with the new MRF methods agree with classical spin echo measurements and are independent of the B1 field profile. When using view sharing reconstruction, results remained accurate (error <10%) when sampling under 10% of k‐space from the 3D data. Conclusion The methods demonstrated here can successfully measure T1, T2, and B1. Errors due to slice profile can be substantially reduced by including its effect in the dictionary or acquiring data in 3D. Magn Reson Med 76:1127–1135, 2016. © 2015 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial‐NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non‐commercial and no modifications or adaptations are made. PMID:26509746

  8. B-1a Lymphocytes Attenuate Insulin Resistance

    PubMed Central

    Shen, Lei; Chng, MH; Alonso, Michael N.; Yuan, Robert

    2015-01-01

    Obesity-associated insulin resistance, a common precursor of type 2 diabetes, is characterized by chronic inflammation of tissues, including visceral adipose tissue (VAT). Here we show that B-1a cells, a subpopulation of B lymphocytes, are novel and important regulators of this process. B-1a cells are reduced in frequency in obese high-fat diet (HFD)-fed mice, and EGFP interleukin-10 (IL-10) reporter mice show marked reductions in anti-inflammatory IL-10 production by B cells in vivo during obesity. In VAT, B-1a cells are the dominant producers of B cell–derived IL-10, contributing nearly half of the expressed IL-10 in vivo. Adoptive transfer of B-1a cells into HFD-fed B cell–deficient mice rapidly improves insulin resistance and glucose tolerance through IL-10 and polyclonal IgM-dependent mechanisms, whereas transfer of B-2 cells worsens metabolic disease. Genetic knockdown of B cell–activating factor (BAFF) in HFD-fed mice or treatment with a B-2 cell–depleting, B-1a cell–sparing anti-BAFF antibody attenuates insulin resistance. These findings establish B-1a cells as a new class of immune regulators that maintain metabolic homeostasis and suggest manipulation of these cells as a potential therapy for insulin resistance. PMID:25249575

  9. Subtype-specific role of phospholipase C-beta in bradykinin and LPA signaling through differential binding of different PDZ scaffold proteins.

    PubMed

    Choi, Jung Woong; Lim, Seyoung; Oh, Yong-Seok; Kim, Eung-Kyun; Kim, Sun-Hee; Kim, Yun-Hee; Heo, Kyun; Kim, Jaeyoon; Kim, Jung Kuk; Yang, Yong Ryul; Ryu, Sung Ho; Suh, Pann-Ghill

    2010-07-01

    Among phospholipase C (PLC) isozymes (beta, gamma, delta, epsilon, zeta and eta), PLC-beta plays a key role in G-protein coupled receptor (GPCR)-mediated signaling. PLC-beta subtypes are often overlapped in their distribution, but have unique knock-out phenotypes in organism, suggesting that each subtype may have the different role even within the same type of cells. In this study, we examined the possibility of the differential coupling of each PLC-beta subtype to GPCRs, and explored the molecular mechanism underlying the specificity. Firstly, we found that PLC-beta1 and PLC-beta 3 are activated by bradykinin (BK) or lysophosphatidic acid (LPA), respectively. BK-triggered phosphoinositides hydrolysis and subsequent Ca(2+) mobilization were abolished specifically by PLC-beta1 silencing, whereas LPA-triggered events were by PLC-beta 3 silencing. Secondly, we showed the evidence that PDZ scaffold proteins is a key mediator for the selective coupling between PLC-beta subtype and GPCR. We found PAR-3 mediates physical interaction between PLC-beta1 and BK receptor, while NHERF2 does between PLC-beta 3 and LPA(2) receptor. Consistently, the silencing of PAR-3 or NHERF2 blunted PLC signaling induced by BK or LPA respectively. Taken together, these data suggest that each subtype of PLC-beta is selectively coupled to GPCR via PDZ scaffold proteins in given cell types and plays differential role in the signaling of various GPCRs.

  10. Comparative immunohistochemical localisation of GABA(B1a), GABA(B1b) and GABA(B2) subunits in rat brain, spinal cord and dorsal root ganglion.

    PubMed

    Charles, K J; Evans, M L; Robbins, M J; Calver, A R; Leslie, R A; Pangalos, M N

    2001-01-01

    GABA(B) receptors are G-protein-coupled receptors mediating the slow onset and prolonged synaptic actions of GABA in the CNS. The recent cloning of two genes, GABA(B1) and GABA(B2), has revealed a novel requirement for GABA(B) receptor signalling. Studies have demonstrated that the two receptor subunits associate as a GABA(B1)/GABA(B2) heterodimer to form a functional GABA(B) receptor. In this study we have developed polyclonal antisera specific to two splice variants of the GABA(B1) subunit, GABA(B1a) and GABA(B1b), as well as an antiserum to the GABA(B2) subunit. Using affinity-purified antibodies derived from these antisera we have mapped out the distribution profile of each subunit in rat brain, spinal cord and dorsal root ganglion. In brain the highest areas of GABA(B1a), GABA(B1b) and GABA(B2) subunit expression were found in neocortex, hippocampus, thalamus, cerebellum and habenula. In spinal cord, GABA(B1) and GABA(B2) subunits were expressed in the superficial layers of the dorsal horn, as well as in motor neurones in the deeper layers of the ventral horn. GABA(B) receptor subunit immunoreactivity in dorsal root ganglion suggested that expression of GABA(B1b) was restricted to the large diameter neurones, in contrast to GABA(B1a) and GABA(B2) subunits which were expressed in both large and small diameter neurones. Although expression levels of GABA(B1) and GABA(B2) subunits varied we found no areas in which GABA(B1) was expressed in the absence of GABA(B2). This suggests that most, if not all, GABA(B1) immunoreactivity may represent functional GABA(B) receptors. Although our data are in general agreement with functional studies, some discrepancies in GABA(B1) subunit expression occurred with respect to other immunohistochemical studies. Overall our data suggest that GABA(B) receptors are widely expressed throughout the brain and spinal cord, and that GABA(B1a) and GABA(B1b) subunits can associate with GABA(B2) to form both pre- and post-synaptic receptors.

  11. Aflatoxin B1 in common Egyptian foods.

    PubMed

    Selim, M I; Popendorf, W; Ibrahim, M S; el Sharkawy, S; el Kashory, E S

    1996-01-01

    Samples of common Egyptian foods (17 nuts and seeds, 10 spices, 31 herbs and medicinal plants, 12 dried vegetables, and 28 cereal grains) were collected from markets in Cairo and Giza. A portion of each sample was extracted with chloroform, and the concentrated extract was cleaned by passing through a silica gel column. Aflatoxin B1 was determined by reversed-phase liquid chromatography with UV detection. The highest prevalence of aflatoxin B1 was in nuts and seeds (82%), followed by spices (40%), herbs and medicinal plants (29%), dried vegetables (25%), and cereal grains (21%). The highest mean concentration of aflatoxin B1 was in herb and medicinal plants (49 ppb), followed by cereals (36 ppb), spices (25 ppb), nuts and seeds (24 ppb), and dried vegetables (20 ppb). Among nuts and seeds, the prevalence of aflatoxin B1 was highest (100%) in watermelon seeds, inshell peanuts, and unshelled peanuts. The lowest prevalence and concentrations were in hommos (garbanzo beans). The highest concentrations of aflatoxin B1 were detected in foods that had no potential for field contamination but required drying during processing and storage, such as pomegranate peel, watermelon seeds, and molokhia.

  12. Effect of an inhaled neutral endopeptidase inhibitor, phosphoramidon, on baseline airway calibre and bronchial responsiveness to bradykinin in asthma.

    PubMed Central

    Crimi, N.; Polosa, R.; Pulvirenti, G.; Magrì, S.; Santonocito, G.; Prosperini, G.; Mastruzzo, C.; Mistretta, A.

    1995-01-01

    BACKGROUND--Bradykinin is a potent vasoactive peptide which has been proposed as an important inflammatory mediator in asthma since it provokes potent bronchoconstriction in asthmatic subjects. Little is known at present about the potential role of lung peptidases in modulating bradykinin-induced airway dysfunction in vivo in man. The change in bronchial reactivity to bradykinin was therefore investigated after treatment with inhaled phosphoramidon, a potent neutral endopeptidase (NEP) inhibitor, in a double blind, placebo controlled, randomised study of 10 asthmatic subjects. METHODS--Subjects attended on six separate occasions at the same time of day during which concentration-response studies with inhaled bradykinin and histamine were carried out, without treatment and after each test drug. Subjects received nebulised phosphoramidon sodium salt (10(-5) M, 3 ml) or matched placebo for 5-7 minutes using an Inspiron Mini-neb nebuliser 5 minutes before the bronchoprovocation test with bradykinin or histamine. Agonists were administered in increasing concentrations as an aerosol generated from a starting volume of 3 ml in a nebuliser driven by compressed air at 8 1/min. Changes in airway calibre were measured as forced expiratory volume in one second (FEV1) and responsiveness as the provocative concentration causing a 20% fall in FEV1 (PC20). RESULTS--Phosphoramidon administration caused a transient fall in FEV1 from baseline, FEV1 values decreasing 6.3% and 5.3% on the bradykinin and histamine study days, respectively. When compared with placebo, phosphoramidon elicited a small enhancement of the airways response to bradykinin, the geometric mean PC20 value (range) decreasing from 0.281 (0.015-5.575) to 0.136 (0.006-2.061) mg/ml. In contrast, NEP blockade failed to alter the airways response to a subsequent inhalation with histamine, the geometric mean (range) PC20 histamine value of 1.65 (0.17-10.52) mg/ml after placebo being no different from that of 1.58 (0

  13. SH2B1 regulation of energy balance, body weight, and glucose metabolism.

    PubMed

    Rui, Liangyou

    2014-08-15

    The Src homology 2B (SH2B) family members (SH2B1, SH2B2 and SH2B3) are adaptor signaling proteins containing characteristic SH2 and PH domains. SH2B1 (also called SH2-B and PSM) and SH2B2 (also called APS) are able to form homo- or hetero-dimers via their N-terminal dimerization domains. Their C-terminal SH2 domains bind to tyrosyl phosphorylated proteins, including Janus kinase 2 (JAK2), TrkA, insulin receptors, insulin-like growth factor-1 receptors, insulin receptor substrate-1 (IRS1), and IRS2. SH2B1 enhances leptin signaling by both stimulating JAK2 activity and assembling a JAK2/IRS1/2 signaling complex. SH2B1 promotes insulin signaling by both enhancing insulin receptor catalytic activity and protecting against dephosphorylation of IRS proteins. Accordingly, genetic deletion of SH2B1 results in severe leptin resistance, insulin resistance, hyperphagia, obesity, and type 2 diabetes in mice. Neuron-specific overexpression of SH2B1β transgenes protects against diet-induced obesity and insulin resistance. SH2B1 in pancreatic β cells promotes β cell expansion and insulin secretion to counteract insulin resistance in obesity. Moreover, numerous SH2B1 mutations are genetically linked to leptin resistance, insulin resistance, obesity, and type 2 diabetes in humans. Unlike SH2B1, SH2B2 and SH2B3 are not required for the maintenance of normal energy and glucose homeostasis. The metabolic function of the SH2B family is conserved from insects to humans.

  14. Dynamic Transition States of ErbB1 Phosphorylation Predicted by Spatial Stochastic Modeling

    PubMed Central

    Pryor, Meghan McCabe; Low-Nam, Shalini T.; Halász, Ádám M.; Lidke, Diane S.; Wilson, Bridget S.; Edwards, Jeremy S.

    2013-01-01

    ErbB1 overexpression is strongly linked to carcinogenesis, motivating better understanding of erbB1 dimerization and activation. Recent single-particle-tracking data have provided improved measures of dimer lifetimes and strong evidence that transient receptor coconfinement promotes repeated interactions between erbB1 monomers. Here, spatial stochastic simulations explore the potential impact of these parameters on erbB1 phosphorylation kinetics. This rule-based mathematical model incorporates structural evidence for conformational flux of the erbB1 extracellular domains, as well as asymmetrical orientation of erbB1 cytoplasmic kinase domains during dimerization. The asymmetric dimer model considers the theoretical consequences of restricted transactivation of erbB1 receptors within a dimer, where the N-lobe of one monomer docks with the C-lobe of the second monomer and triggers its catalytic activity. The dynamic nature of the erbB1 phosphorylation state is shown by monitoring activation states of individual monomers as they diffuse, bind, and rebind after ligand addition. The model reveals the complex interplay between interacting liganded and nonliganded species and the influence of their distribution and abundance within features of the membrane landscape. PMID:24048005

  15. Presenilin-dependent intramembrane cleavage of ephrin-B1

    PubMed Central

    Tomita, Taisuke; Tanaka, Sayaka; Morohashi, Yuichi; Iwatsubo, Takeshi

    2006-01-01

    Background Presenilin-dependent γ-secretase cleavage of several transmembrane proteins, including amyloid-β precursor protein and Notch, mediates the intramembrane proteolysis to liberate their intracellular domains that are involved in cellular signaling. Considering γ-secretase inhibitors as therapeutics for Alzheimer's disease, understanding the physiologically and biologically important substrate for γ-secretase activity in brains is emerging issue. To elucidate the molecular mechanism and physiological role of γ-secretase, we screened candidate molecules for γ-secretase substrates. Results We show that ephrin-B1, that participates in cell-cell repulsive and attractive signaling together with its Eph receptor, constitutively undergoes ectodomain shedding and that the residual membrane-tethered fragment is sequentially cleaved by γ-secretase to release the intracellular domain. Furthermore, overexpression of membrane-tethered ephrin-B1 caused protrusion of numerous cellular processes consisted of F-actin, that required the preservation of the most C-terminal region of ephrin-B1. In contrast, soluble intracellular domain translocated into the nucleus and had no effect on cell morphology. Conclusion Our findings suggest that ephrin-B is a genuine substrate for γ-secretase and regulates the cytoskeletal dynamics through intramembrane proteolysis. PMID:16930449

  16. H/D exchange of gas phase bradykinin ions in a linear quadrupole ion trap.

    PubMed

    Mao, Dunmin; Douglas, D J

    2003-02-01

    The gas phase H/D exchange reaction of bradykinin ions, as well as fragment ions of bradykinin generated through collisions in an orifice skimmer region, have been studied with a linear quadrupole ion trap (LIT) reflectron time-of-flight (rTOF) mass spectrometer system. The reaction in the trap takes only tens of seconds at a pressure of few mTorr of D2O or CD3OD. The exchange rate and hydrogen exchange level are not sensitive to the trapping q value over a broad range, provided q is not close to the stability boundary (q = 0.908). The relative rates and hydrogen exchange levels of protonated and sodiated +1 and +2 ions are similar to those observed previously by others with a Fourier transform ion cyclotron resonance (FTICR) mass spectrometer system. The doubly and triply protonated ions show multimodal isotopic distributions, suggesting the presence of several different conformations. The y fragment ions show greater exchange rates and levels than a or b ions, and when water or ammonia is lost from the fragment ions, no exchange is observed.

  17. 7 CFR 1b.1 - Purpose.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Secretary of Agriculture NATIONAL ENVIRONMENTAL POLICY ACT § 1b.1 Purpose. (a) This part supplements the regulations for implementation of the National Environmental Policy Act (NEPA), for which regulations were published by the Council on Environmental Quality (CEQ) in 40 CFR parts 1500 through 1508. This...

  18. Predictive value of serum bradykinin and desArg9-bradykinin levels for chemotherapeutic responses in active tuberculosis patients: A retrospective case series

    PubMed Central

    Qian, Xu; Nguyen, Duc T.M.; Li, Yaojun; Lyu, Jianxin; Graviss, Edward A.; Hu, Tony Y.

    2016-01-01

    Background There is an urgent need for methods that can rapidly and accurately assess therapeutic responses in patients with active tuberculosis (TB) in order to predict treatment outcomes. Exposure to bacterial pathogens can rapidly activate the plasma contact system, triggering the release of bradykinin (BK) and its metabolite desArg9-bradykinin (DABK) to induce inflammation and innate immune responses. We hypothesized that serum BK and DABK levels might act as sensitive immune response signatures for changes in Mycobacterium tuberculosis (Mtb) burden, and therefore examined how serum levels of these markers corresponded with anti-TB therapy in a small cohort of active TB cases. Methods Nanotrap Mass-Spectrometry (MS) was used to analyze serial blood specimens from 13 HIV-negative adults with microbiologically confirmed active TB who were treated with first-line anti-TB chemotherapy. MS signal for BK (m/z 1060.5) and DABK (m/z 904.5) serum peptides were evaluated at multiple time-points (before, during, and after treatment) to evaluate how BK and DABK levels corresponded with disease status. Results Serum BK levels declined from pretreatment baseline levels during the early stage anti-TB therapy (induction phase) and tended to remain below baseline levels during extended treatment (consolidation phase) and after therapy completion. BK levels were consistent with induction phase sputum culture conversions indicative of decreased Mtb burden reflecting good treatment responses. Serum DABK levels tended to increase during the induction phase and decrease at consolidation and post-therapy time points, which may indicate a shift from active disease to chronic inflammation to a disease free state. Elevated BK and DABK levels after treatment completion in one patient may be related to the subsequent recurrent TB disease. Conclusions Our pilot data suggests that changes in the circulating BK and DABK levels in adult TB patients can be used as potential surrogate markers

  19. Human airway smooth muscle cells secrete amphiregulin via bradykinin/COX-2/PGE2, inducing COX-2, CXCL8, and VEGF expression in airway epithelial cells

    PubMed Central

    Knox, Alan J.

    2015-01-01

    Human airway smooth muscle cells (HASMC) contribute to asthma pathophysiology through an increased smooth muscle mass and elevated cytokine/chemokine output. Little is known about how HASMC and the airway epithelium interact to regulate chronic airway inflammation and remodeling. Amphiregulin is a member of the family of epidermal growth factor receptor (EGFR) agonists with cell growth and proinflammatory roles and increased expression in the lungs of asthma patients. Here we show that bradykinin (BK) stimulation of HASMC increases amphiregulin secretion in a mechanism dependent on BK-induced COX-2 expression, increased PGE2 output, and the stimulation of HASMC EP2 and EP4 receptors. Conditioned medium from BK treated HASMC induced CXCL8, VEGF, and COX-2 mRNA and protein accumulation in airway epithelial cells, which were blocked by anti-amphiregulin antibodies and amphiregulin siRNA, suggesting a paracrine effect of HASMC-derived amphiregulin on airway epithelial cells. Consistent with this, recombinant amphiregulin induced CXCL8, VEGF, and COX-2 in airway epithelial cells. Finally, we found that conditioned media from amphiregulin-stimulated airway epithelial cells induced amphiregulin expression in HASMC and that this was dependent on airway epithelial cell COX-2 activity. Our study provides evidence of a dynamic axis of interaction between HASMC and epithelial cells that amplifies CXCL8, VEGF, COX-2, and amphiregulin production. PMID:26047642

  20. Human SH2B1 mutations are associated with maladaptive behaviors and obesity.

    PubMed

    Doche, Michael E; Bochukova, Elena G; Su, Hsiao-Wen; Pearce, Laura R; Keogh, Julia M; Henning, Elana; Cline, Joel M; Saeed, Sadia; Dale, Anne; Cheetham, Tim; Barroso, Inês; Argetsinger, Lawrence S; O'Rahilly, Stephen; Rui, Liangyou; Carter-Su, Christin; Farooqi, I Sadaf

    2012-12-01

    Src homology 2 B adapter protein 1 (SH2B1) modulates signaling by a variety of ligands that bind to receptor tyrosine kinases or JAK-associated cytokine receptors, including leptin, insulin, growth hormone (GH), and nerve growth factor (NGF). Targeted deletion of Sh2b1 in mice results in increased food intake, obesity, and insulin resistance, with an intermediate phenotype seen in heterozygous null mice on a high-fat diet. We identified SH2B1 loss-of-function mutations in a large cohort of patients with severe early-onset obesity. Mutation carriers exhibited hyperphagia, childhood-onset obesity, disproportionate insulin resistance, and reduced final height as adults. Unexpectedly, mutation carriers exhibited a spectrum of behavioral abnormalities that were not reported in controls, including social isolation and aggression. We conclude that SH2B1 plays a critical role in the control of human food intake and body weight and is implicated in maladaptive human behavior.

  1. Ca(2+)-dependent non-selective cation and potassium channels activated by bradykinin in pig coronary artery endothelial cells.

    PubMed Central

    Baron, A; Frieden, M; Chabaud, F; Bény, J L

    1996-01-01

    1. Using the cell-attached and inside-out modes of the patch-clamp technique, we studied the Ca(2+)-dependent ionic channels activated by bradykinin in cultured pig coronary artery endothelial cells to further understand electrophysiological events underlying cellular activation. 2. In the cell-attached mode, bradykinin (94 nM) activated two types of Ca(2+)-dependent channels: a high conductance K+ channel (285 pS in high symmetrical K+), whose open state probability was increased by depolarization, and a lower conductance inwardly rectifying non-selective cation channel (44 pS in high symmetrical K+). 3. The 285 pS K+ channel was half-maximally activated by cytosolic Ca2+ levels of 1.6 and 4.5 microM at +10 and -30 mV, respectively. Such local concentrations should be reached in the presence of bradykinin, which induces a mean maximal cytosolic Ca2+ rise of 1.3 microM. 4. The 285 pS K+ channel was inhibited by d-tubocurarine, which acted by reducing the mean open time duration (flickering pattern), finally reducing the channel conductance. 5. Divalent cations such as Ca2+ could flow through the 44 pS non-selective cation channel, with nearly the same permeability (P) as monovalent cations (PK: PNa: PCa = 1:1:0.7). 6. The cation channel appeared to be more sensitive to Ca2+ than the K+ channel, with a half-maximal open probability induced by 0.7 microM Ca2+ on the intracellular side of the membrane. 7. In contrast to the K+ channel, the cation channel mean open time was clearly increased by bradykinin. This effect was delayed compared with the increase in the channel open state probability and was rapidly lost in the inside-out configuration. Caffeine also activated the cation channel but more transiently than bradykinin and without any effect on the open duration. 8. In the absence of extracellular Ca2+, the bradykinin-induced increase in cytosolic free Ca2+ was shortened temporally by 52% and reduced in amplitude by 88%, whereas the bradykinin

  2. Functional characterisation of a TLR accessory protein, UNC93B1, in Atlantic salmon (Salmo salar).

    PubMed

    Lee, P T; Zou, J; Holland, J W; Martin, S A M; Scott, C J W; Kanellos, T; Secombes, C J

    2015-05-01

    Toll-like receptors (TLRs) are indispensable components of the innate immune system, which recognise conserved pathogen associated molecular patterns (PAMPs) and induce a series of defensive immune responses to protect the host. Biosynthesis, localisation and activation of TLRs are dependent on TLR accessory proteins. In this study, we identified the accessory protein, UNC93B1, from Atlantic salmon (Salmo salar) whole-genome shotgun (WGS) contigs aided by the conserved gene synteny of genes flanking UNC93B1 in fish, birds and mammals. Phylogenetic analysis showed that salmon UNC93B1 grouped with other vertebrate UNC93B1 molecules, and had highest amino acid identity and similarity to zebrafish UNC93B1. The salmon UNC93B1 gene organisation was also similar in structure to mammalian UNC93B1. Our gene expression studies revealed that salmon UNC93B1 was more highly expressed in spleen, liver and gill tissues but was expressed at a lower level in head kidney tissue in post-smolts relative to parr. Moreover, salmon UNC93B1 mRNA transcripts were up-regulated in vivo in spleen tissue from polyI:C treated salmon and in vitro in polyI:C or IFNγ stimulated Salmon Head Kidney-1 (SHK-1) cells. Initial studies into the functional role of salmon UNC93B1 in fish TLR signalling found that both wild type salmon UNC93B1 and a molecule with a site-directed mutation (H424R) co-immunoprecipitated with salmon TLR19, TLR20a and TLR20d. Overall, these data illustrate the potential importance of UNC93B1 as an accessory protein in fish TLR signalling.

  3. Feasibility Study B-1 Power Controller.

    DTIC Science & Technology

    1979-11-01

    Study performed by the Autonetics Strategic Systems Division ( ASSD ) of Rockwell International on Contract N62269-79-C-0294. The objective of this study...Modify the design of the ASSD B-1 SSPC, Part Number 12880-507-1, to be a 115 Vac quadruple SSPC unit, with a SOSTEL compatible interface. 3.1.2 115 Vac...Primary Power Modifications. The ASSD SSPC Unit, Appendix A, contains four identical PC’s operating from 230 Vac primary power. Referring to Figure 1

  4. B-1 AFT Nacelle Flow Visualization Study

    NASA Technical Reports Server (NTRS)

    Celniker, Robert

    1975-01-01

    A 2-month program was conducted to perform engineering evaluation and design tasks to prepare for visualization and photography of the airflow along the aft portion of the B-1 nacelles and nozzles during flight test. Several methods of visualizing the flow were investigated and compared with respect to cost, impact of the device on the flow patterns, suitability for use in the flight environment, and operability throughout the flight. Data were based on a literature search and discussions with the test personnel. Tufts were selected as the flow visualization device in preference to several other devices studied. A tuft installation pattern has been prepared for the right-hand aft nacelle area of B-1 air vehicle No.2. Flight research programs to develop flow visualization devices other than tufts for use in future testing are recommended. A design study was conducted to select a suitable motion picture camera, to select the camera location, and to prepare engineering drawings sufficient to permit installation of the camera. Ten locations on the air vehicle were evaluated before the selection of the location in the horizontal stabilizer actuator fairing. The considerations included cost, camera angle, available volume, environmental control, flutter impact, and interference with antennas or other instrumentation.

  5. Nematode and Arthropod Genomes Provide New Insights into the Evolution of Class 2 B1 GPCRs

    PubMed Central

    Cardoso, João C. R.; Félix, Rute C.; Power, Deborah M.

    2014-01-01

    Nematodes and arthropods are the most speciose animal groups and possess Class 2 B1 G-protein coupled receptors (GPCRs). Existing models of invertebrate Class 2 B1 GPCR evolution are mainly centered on Caenorhabditis elegans and Drosophila melanogaster and a few other nematode and arthropod representatives. The present study reevaluates the evolution of metazoan Class 2 B1 GPCRs and orthologues by exploring the receptors in several nematode and arthropod genomes and comparing them to the human receptors. Three novel receptor phylogenetic clusters were identified and designated cluster A, cluster B and PDF-R-related cluster. Clusters A and B were identified in several nematode and arthropod genomes but were absent from D. melanogaster and Culicidae genomes, whereas the majority of the members of the PDF-R-related cluster were from nematodes. Cluster A receptors were nematode and arthropod-specific but shared a conserved gene environment with human receptor loci. Cluster B members were orthologous to human GCGR, PTHR and Secretin members with which they probably shared a common origin. PDF-R and PDF-R related clusters were present in representatives of both nematodes and arthropods. The results of comparative analysis of GPCR evolution and diversity in protostomes confirm previous notions that C. elegans and D. melanogaster genomes are not good representatives of nematode and arthropod phyla. We hypothesize that at least four ancestral Class 2 B1 genes emerged early in the metazoan radiation, which after the protostome-deuterostome split underwent distinct selective pressures that resulted in duplication and deletion events that originated the current Class 2 B1 GPCRs in nematode and arthropod genomes. PMID:24651821

  6. Nematode and arthropod genomes provide new insights into the evolution of class 2 B1 GPCRs.

    PubMed

    Cardoso, João C R; Félix, Rute C; Power, Deborah M

    2014-01-01

    Nematodes and arthropods are the most speciose animal groups and possess Class 2 B1 G-protein coupled receptors (GPCRs). Existing models of invertebrate Class 2 B1 GPCR evolution are mainly centered on Caenorhabditis elegans and Drosophila melanogaster and a few other nematode and arthropod representatives. The present study reevaluates the evolution of metazoan Class 2 B1 GPCRs and orthologues by exploring the receptors in several nematode and arthropod genomes and comparing them to the human receptors. Three novel receptor phylogenetic clusters were identified and designated cluster A, cluster B and PDF-R-related cluster. Clusters A and B were identified in several nematode and arthropod genomes but were absent from D. melanogaster and Culicidae genomes, whereas the majority of the members of the PDF-R-related cluster were from nematodes. Cluster A receptors were nematode and arthropod-specific but shared a conserved gene environment with human receptor loci. Cluster B members were orthologous to human GCGR, PTHR and Secretin members with which they probably shared a common origin. PDF-R and PDF-R related clusters were present in representatives of both nematodes and arthropods. The results of comparative analysis of GPCR evolution and diversity in protostomes confirm previous notions that C. elegans and D. melanogaster genomes are not good representatives of nematode and arthropod phyla. We hypothesize that at least four ancestral Class 2 B1 genes emerged early in the metazoan radiation, which after the protostome-deuterostome split underwent distinct selective pressures that resulted in duplication and deletion events that originated the current Class 2 B1 GPCRs in nematode and arthropod genomes.

  7. 118-B-1 excavation treatability test procedures

    SciTech Connect

    Frain, J.M.

    1994-08-01

    This treatability study has two purposes: to support development of the approach to be used for burial ground remediation, and to provide specific engineering information for the design of burial grounds receiving waste generated from the 100 Area removal actions. Data generated from this test will also provide performance and cost information necessary for detailed analysis of alternatives for burial ground remediation. Further details on the test requirements, milestones and data quality objectives are described in detail in the 118-B-1 Excavation Treatability Test Plan (DOE/RL-94-43). These working procedures are intended for use by field personnel to implement the requirements of the milestone. A copy of the detailed Test Plan will be kept on file at the on-site field support trailer, and will be available for review by field personnel.

  8. 118-B-1 excavation treatability test plan

    SciTech Connect

    Not Available

    1994-07-01

    The Hanford 118-B-1 Burial Ground Treatability Study has been required by milestone change request {number_sign}M-15-93-04, dated September 30, 1993. The change request requires that a treatability test be conducted at the 100-B Area to obtain additional engineering information for remedial design of burial grounds receiving waste from 100 Area removal actions. This treatability study has two purposes: (1) to support development of the Proposed Plan (PP) and Record of Decision (ROD), which will identify the approach to be used for burial ground remediation, and (2) to provide specific engineering information for receiving waste generated from the 100 Area removal actions. Data generated from this test also will provide critical performance and cost information necessary for remedy evaluation in the detailed analysis of alternatives during preparation of the focused feasibility study (FFS). This treatability testing supports the following 100 Area alternatives: (1) excavation and disposal, and (2) excavation, sorting, (treatment), and disposal.

  9. Neurotransmitter-blocking agents influence antinociceptive effects of carbamazepine, baclofen, pentazocine and morphine on bradykinin-induced trigeminal pain.

    PubMed

    Foong, F W; Satoh, M

    1984-06-01

    The influence of naloxone (a narcotic antagonist), bicuculline (a GABA antagonist), phentolamine (an alpha-blocking agent), propranolol (a beta-adrenergic blocking agent), haloperidol (a dopaminergic blocking agent), methysergide (a serotonergic blocking agent) and atropine (a muscarinic blocking agent), on the antinociceptive effects induced by carbamazepine, baclofen, pentazocine and morphine, were investigated with a new antinociception test, using the trigeminal pain induced by application of bradykinin onto the tooth pulp of the rat. The antinociceptive effect of carbamazepine was significantly inhibited by bicuculline, phentolamine, propranolol and haloperidol but not by naloxone, methysergide and atropine. The effect of baclofen was significantly reduced by naloxone, bicuculline, propranolol and atropine but not by phentolamine, haloperidol and methysergide. The antinociceptive actions of pentazocine and morphine on trigeminal pain were significantly reduced by naloxone and phentolamine, and by naloxone alone, respectively. These results suggest the involvement of different neurotransmitters in the antinociceptive effects of the four analgesic drugs on trigeminal pain induced by bradykinin.

  10. An Overview of B-1 Cells as Antigen-Presenting Cells

    PubMed Central

    Popi, Ana F.; Longo-Maugéri, Ieda M.; Mariano, Mario

    2016-01-01

    The role of B cells as antigen-presenting cells (APCs) has been extensively studied, mainly in relation to the activation of memory T cells. Considering the B cell subtypes, the role of B-1 cells as APCs is beginning to be explored. Initially, it was described that B-1 cells are activated preferentially by T-independent antigens. However, some reports demonstrated that these cells are also involved in a T-dependent response. The aim of this review is to summarize information about the ability of B-1 cells to play a role as APCs and to briefly discuss the role of the BCR and toll-like receptor signals in this process. Furthermore, some characteristics of B-1 cells, such as natural IgM production and phagocytic ability, could interfere in the participation of these cells in the onset of an adaptive response. PMID:27148259

  11. IL-15 temporally reorients IL-10 biased B-1a cells toward IL-12 expression.

    PubMed

    Kanti Ghosh, Amlan; Sinha, Debolina; Mukherjee, Subhadeep; Biswas, Ratna; Biswas, Tapas

    2016-03-01

    Interleukin (IL)-15 is known to strongly modulate T-cell function; however, its role in controlling mucosal immunity, including its ability to modulate B-1a cell activity, remains to be elucidated. Here, we show that IL-15 upregulates activation molecules and the costimulatory molecule CD80 on viable B-1a cells. Cell activation was accompanied by the depletion of sialic acid-binding immunoglobulin-like lectin (Siglec)-G, an inhibitor of cell activation that is present on B-1a cells. The IL-15 receptor CD122 was stimulated on B-1a cells by the cytokine showing its direct involvement in IL-15-mediated responses. IL-10 is responsible for the long term survival of B-1a cells in culture, which is initially promoted by IL-15. The upregulation of IL-10 was followed by the appearance of suppressor of cytokine signaling (SOCS)1 in the presence of IL-15 and the loss of IL-10. This resulted in the cells switching to IL-12 expression. This anti-inflammatory to pro-inflammatory shift in the B-1a cell character was independent of the cell-specific marker CD5, which remained highly expressed throughout the in vitro life of the cells. The presence of the immunosuppressive receptor programmed cell death (PD)-1 and its ligand PD-L2 were features of a predominantly IL-10 response. PD-1 and PD-L2 can mediate juxtacrine signaling. However, the abrogation of PD-1 and its ligand was observed when the cells expressed IL-12. This demonstrates an inverse relationship between the receptor and ligand and the pro-inflammatory cytokine. The induction of IgM and IgA, which can play pivotal roles in mucosal immunity, was promoted in the presence of IL-15. Collectively, the data implicate IL-15 as the master cytokine that induces B-1a cells to mount a mucosal immune response.

  12. Resveratrol protects SR-B1 levels in keratinocytes exposed to cigarette smoke.

    PubMed

    Sticozzi, C; Belmonte, G; Cervellati, F; Muresan, X M; Pessina, F; Lim, Y; Forman, H J; Valacchi, G

    2014-04-01

    Cigarette smoking (CS) has been strongly linked to several health conditions including heart disease, lung cancer, and other respiratory and circulatory ailments. Deleterious effects of cigarette smoking on skin have also been well documented, but unlike effects on other organs, damage does not depend upon inhalation. The upper layer of the skin, the stratum corneum (rich in cholesterol fatty acids and ceramide), is very susceptible to damage induced by exposure to environmental stressors that can modify its lipid composition and thereby affect its function of protecting skin from dehydration. Scavenger receptor B1 (SR-B1) is involved in the uptake of cholesterol in several tissues including skin. We previously demonstrated that CS exposure induces formation of aldehyde (HNE) adducts that decrease SR-B1 expression. As topical resveratrol, a well-known polyphenolic stilbene, has been demonstrated to show benefits against skin disorders, we investigated its possible role as a protective agent against CS-induced reduction of SR-B1 expression in cutaneous tissue. In this study, we demonstrate that resveratrol at doses ranging from 0.5 to 10 μM is not toxic and is able to increase SR-B1 protein levels in a dose-dependent manner in human keratinocytes. Moreover, when the cells that were pretreated with various doses of resveratrol were exposed to CS, the loss of SR-B1 was prevented in a dose-dependent manner. In addition, in keratinocytes, resveratrol was also able to prevent an increase in HNE-protein adducts induced by CS. In particular resveratrol was able to prevent HNE-SR-B1 adduct formation. Thus, resveratrol seems to be a natural compound that could provide skin with a defense against exogenous stressors by protecting the essential cholesterol receptor, SR-B1.

  13. Analgesic and anti-inflammatory actions on bradykinin route of a polysulfated fraction from alga Ulva lactuca.

    PubMed

    de Araújo, Ianna Wivianne Fernandes; Rodrigues, José Ariévilo Gurgel; Quinderé, Ana Luíza Gomes; Silva, Jane de Fátima Teixeira; Maciel, Gabrielle de Freitas; Ribeiro, Natássia Albuquerque; de Sousa Oliveira Vanderlei, Edfranck; Ribeiro, Kátia Alves; Chaves, Hellíada Vasconcelos; Pereira, Karuza Maria Alves; Bezerra, Mirna Marques; Benevides, Norma Maria Barros

    2016-11-01

    We investigated structural features of polysaccharides from Ulva lactuca and their effects on the classical models of nociception and inflammation. Crude extract was obtained by enzymatic digestion and isolated by ion exchange chromatography on DEAE-cellulose. The fraction with higher yield was used in the tests (SP-Ul). Swiss mice received SP-Ul (1, 3 or 9mg/kg; i.v.), 30min prior to injection of 0.8%-acetic acid or 1%-formalin or prior to a thermal stimulus. At same doses, SP-Ul was tested on Wistar rats on paw edema elicited by different irritants (carrageenan, dextran, bradykinin, histamine or serotonin). The results of infrared characterization indicated the presence of hydroxyl groups, sulfate, uronic acid and glycosidic linkages in all SP fractions spectrums. SP-Ul decreased significantly the antinociception in response to acetic acid or formalin (second phase), but not in the hot-plate test, suggesting that its analgesia occurs through a peripheral mechanism. SP-Ul did not reduce carrageenan-induced paw edema as supported by both histological and myeloperoxidase activity assessments. However, SP-Ul (1mg/kg; s.c.) reduced dextran-elicited edema, showing vascular anti-inflammatory effect, with bradykinin as major target because it did not reduce histamine- and serotonin-induced paw edemas. Therefore, SP-Ul acts on bradykinin pathway in its antinociceptive and anti-inflammatory responses.

  14. In vivo Metabolism of Hydrolyzed Fumonisin B1 and Fumonisin B1

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fumonisin B1 (FB1) is the most prevalent fumonisin mycotoxin found in corn and corn-based foods. It inhibits ceramide synthase, disrupts sphingolipid metabolism and function, is toxic to animals, causes cancer in rodents, and induces neural tube defects in some mouse strains. Its human health effect...

  15. Transcapillary exchange in the cat salivary gland during secretion, bradykinin infusion and after chronic duct ligation.

    PubMed Central

    Mann, G E; Smaje, L H; Yudilevich, D L

    1979-01-01

    1. Capillary permeability-surface area products for 86Rb, [51Cr]EDTA (mol. wt. 357), [57Co]cyanocobalamin (mol. wt. 1353) and [125I]insulin (approximate mol. wt. 6000) have been measured using the single-circulation, multiple-tracer dilution technique in the in situ perfused submandibular salivary gland during parasympathetic nerve stimulation, close-arterial bradykinin infusion and following chronic duct ligation. 2. In glands with a natural blood supply, permeability-surface area for 86Rb and [51Cr]EDTA increased during parasympathetic stimulation, but this was shown to be related to the concomitant increase in blood flow rather than to a change in capillary permeability or in surface area. 3. In glands perfused at constant flow, parasympathetic stimulation led to a decrease in permeability-surface area for EDTA (-19.1 +/- 5.2%, mean +/- S.E., n = 5, P less than 0.05) cyanocobalamin (-12.3 +/- 6.0, n = 12, P less than 0.05), and insulin (-15.3 +/- 4.8, n = 11, P less than 0.02). It is suggested that this may be the result of a redistribution of flow from the acinar microcirculation to a less permeable ductal vasculature. 4. Bradykinin infusion had no significant effect on permeability-surface area for EDTA and cyanocobalamin in perfused glands. 5. In perfused glands, ligation of the submandibular duct for 3--12 days reduced permeability-surface area (ml.min-1.g-1) for [51Cr]EDTA from 5.26 +/- 0.60 (mean +/- S.E., n = 9) to 4.20 +/- 0.12 (n = 4, P less than 0.30), [57Co]cyanocobalamin from 3.22 +/- 0.12 (n = 48) to 2.02 +/- 0.08 (n = 15, P less than 0.001) and [125I]insulin from 1.52 +/- 0.07 (n = 39) to 0.72 +/- 0.23 (n = 11, P less than 0.001). PMID:119844

  16. Vitamin B1 (thiamine) and dementia.

    PubMed

    Gibson, Gary E; Hirsch, Joseph A; Fonzetti, Pasquale; Jordan, Barry D; Cirio, Rosanna T; Elder, Jessica

    2016-03-01

    The earliest and perhaps best example of an interaction between nutrition and dementia is related to thiamine (vitamin B1). Throughout the last century, research showed that thiamine deficiency is associated with neurological problems, including cognitive deficits and encephalopathy. Multiple similarities exist between classical thiamine deficiency and Alzheimer's disease (AD) in that both are associated with cognitive deficits and reductions in brain glucose metabolism. Thiamine-dependent enzymes are critical components of glucose metabolism that are reduced in the brains of AD patients and by thiamine decline, and a decrease in their levels could account for the reduction in glucose metabolism. In preclinical models, reduced thiamine can drive AD-like abnormalities, including memory deficits, neuritic plaques, and hyperphosphorylation of tau. Furthermore, excess thiamine diminishes AD-like pathologies. In addition to dietary deficits, drugs or other manipulations that interfere with thiamine absorption can cause thiamine deficiency. Elucidating the reasons why the brains of AD patients are functionally thiamine deficient and determining the effects of thiamine restoration may provide critical information to help treat patients with AD.

  17. Vitamin B1 (thiamine) and dementia

    PubMed Central

    Gibson, Gary E.; Hirsch, Joseph A.; Fonzetti, Pasquale; Jordon, Barry D.; Cirio, Rosanna T.; Elder, Jessica

    2016-01-01

    The earliest and perhaps best example of an interaction between nutrition and dementia is related to thiamine (vitamin B1). Throughout the last century, research showed that thiamine deficiency is associated with neurological problems, including cognitive deficits and encephalopathy. Multiple similarities exist between classical thiamine deficiency and Alzheimer’s disease (AD) in that both are associated with cognitive deficits and reductions in brain glucose metabolism. Thiamine-dependent enzymes are critical components of glucose metabolism that are reduced in the brains of AD patients and by thiamine deficiency, and their decline could account for the reduction in glucose metabolism. In preclinical models, reduced thiamine can drive AD-like abnormalities, including memory deficits, plaques, and hyperphosphorylation of tau. Furthermore, excess thiamine diminishes AD-like pathologies. In addition to dietary deficits, drugs, or other manipulations that interfere with thiamine absorption can cause thiamine deficiency. Elucidating the reasons why the brains of AD patients are functionally thiamine deficient and determining the effects of thiamine restoration may provide critical information to help treat patients with AD. PMID:26971083

  18. Tobacco smoke induces CYP1B1 in the aerodigestive tract.

    PubMed

    Port, Jeffrey L; Yamaguchi, Kentaro; Du, Baoheng; De Lorenzo, Mariana; Chang, Mindy; Heerdt, Paul M; Kopelovich, Levy; Marcus, Craig B; Altorki, Nasser K; Subbaramaiah, Kotha; Dannenberg, Andrew J

    2004-11-01

    Several members of the P450 family, including cytochrome P450 1B1 (CYP1B1), can convert tobacco smoke (TS) procarcinogens, including benzo[a]pyrene (B[a]P), to carcinogenic intermediates. In this study we investigated the effects of TS condensate and B[a]P on the expression of CYP1B1 in vitro and in vivo. CYP1B1 mRNA and protein were induced by both TS condensate and B[a]P in cell lines derived from the human aerodigestive tract. Treatment with TS condensate stimulated binding of the aryl hydrocarbon receptor (AhR) to an oligonucleotide containing a canonical xenobiotic response element (XRE) site and induced XRE-luciferase activity. These findings are consistent with prior evidence that polycyclic aromatic hydrocarbons, known ligands of the AhR, stimulate CYP1B1 transcription by an XRE-dependent mechanism. To determine whether these in vitro findings applied in vivo, both murine and human studies were carried out. Short-term exposure to TS induced CYP1B1 in the tongue, esophagus, lung and colon of experimental mice. In contrast, CYP1B1 was not induced by TS in the aorta of these mice. Levels of CYP1B1 mRNA were also elevated in the bronchial mucosa of human tobacco smokers versus never smokers (P < 0.05). Taken together, these results support a role for CYP1B1 in TS-induced carcinogenesis in the aerodigestive tract.

  19. Lotus corniculatus regulates the inflammation induced by bradykinin in a murine model of pleurisy.

    PubMed

    Pereira, Diana Ana; Dalmarco, Juliana Bastos; Wisniewski, Alberto; Simionatto, Edésio Luiz; Pizzolatti, Moacir Geraldo; Fröde, Tânia Silvia

    2011-03-23

    This study evaluated the anti-inflammatory efficacy of the crude extract (CE), the fractions derived from hexane (HEX), ethyl acetate (AcOEt), n-butanol (BuOH), and aqueous (Aq) and isolated compounds (oleanolic acid or kaempferitrin) obtained from the aerial parts of Lotus corniculatus var. São Gabriel in mice with bradykinin-induced pleurisy. Swiss mice were used for the In Vivo experiments. Inflammatory parameters [leukocytes; exudate concentrations; myeloperoxidase and adenosine-deaminase activities, and nitric oxide and interleukin-17 levels] were evaluated 4 h after pleurisy induction. The crude extract of Lotus corniculatus, its derived fractions, and isolated compounds inhibited leukocytes and the exudate. This inhibitory effect was associated with decreased of myeloperoxidase and adenosine-deaminase activities, nitric oxide products, and IL-17A levels. Lotus corniculatus presented important anti-inflammatory action by inhibiting leukocyte influx and exudate concentrations. This effect was directly related to the inhibition of nitric oxide and interleukinin17 levels. Oleanolic acid and kaempferitrin can account for these anti-inflammatory effects.

  20. Role of chloride channels in bradykinin-induced guinea pig airway vagal C-fibre activation.

    PubMed

    Lee, Min-Goo; Macglashan, Donald W; Undem, Bradley J

    2005-07-01

    We tested the hypothesis that an ionic current carried by chloride ions contributes to bradykinin (BK)-induced membrane depolarization and activation of vagal afferent C-fibres. In an ex vivo innervated trachea/bronchus preparation, BK (1 microM) consistently produced action potential discharge in vagal afferent C-fibres with receptive fields in the trachea or main stem bronchus. The Ca2+-activated Cl- channel (CLCA) inhibitor, niflumic acid (NFA, 100 microM), significantly reduced BK-induced action potential discharge to 21 +/- 7% of the control BK response. NFA did not inhibit capsaicin-induced or citric-acid-induced action potential discharge in tracheal C-fibres. The inhibitory effect of NFA was mimicked by another CLCA inhibitor, 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB, 100 microM). NFA also inhibited the BK-induced inward current in gramicidin-perforated whole-cell patch-clamp recordings of capsaicin-sensitive jugular ganglion neurones retrogradely labelled from the airways. NFA did not inhibit the BK-induced increase in intracellular free Ca2+. The TRPV1 inhibitor, iodo-resiniferatoxin (1 microM), also partially inhibited BK-induced action potential discharge, and the combination of iodo-resiniferatoxin and NFA virtually abolished the BK-induced action potential discharge. We concluded that in vagal afferent C-fibres, BK evokes membrane depolarization and action potential discharge through the additive effects of TRPV1 and Cl- channel activation.

  1. Functional characterization of obesity-associated variants involving the α and β isoforms of human SH2B1.

    PubMed

    Pearce, Laura R; Joe, Ray; Doche, Michael E; Su, Hsiao-Wen; Keogh, Julia M; Henning, Elana; Argetsinger, Lawrence S; Bochukova, Elena G; Cline, Joel M; Garg, Sumedha; Saeed, Sadia; Shoelson, Steven; O'Rahilly, Stephen; Barroso, Inês; Rui, Liangyou; Farooqi, I Sadaf; Carter-Su, Christin

    2014-09-01

    We have previously reported rare variants in sarcoma (Src) homology 2 (SH2) B adaptor protein 1 (SH2B1) in individuals with obesity, insulin resistance, and maladaptive behavior. Here, we identify 4 additional SH2B1 variants by sequencing 500 individuals with severe early-onset obesity. SH2B1 has 4 alternatively spliced isoforms. One variant (T546A) lies within the N-terminal region common to all isoforms. As shown for past variants in this region, T546A impairs SH2B1β enhancement of nerve growth factor-induced neurite outgrowth, and the individual with the T546A variant exhibits mild developmental delay. The other 3 variants (A663V, V695M, and A723V) lie in the C-terminal tail of SH2B1α. SH2B1α variant carriers were hyperinsulinemic but did not exhibit the behavioral phenotype observed in individuals with SH2B1 variants that disrupt all isoforms. In in vitro assays, SH2B1α, like SH2B1β, enhances insulin- and leptin-induced insulin receptor substrate 2 (IRS2) phosphorylation and GH-induced cell motility. None of the variants affect SH2B1α enhancement of insulin- and leptin-induced IRS2 phosphorylation. However, T546A, A663V, and A723V all impair the ability of SH2B1α to enhance GH-induced cell motility. In contrast to SH2B1β, SH2B1α does not enhance nerve growth factor-induced neurite outgrowth. These studies suggest that genetic variants that disrupt isoforms other than SH2B1β may be functionally significant. Further studies are needed to understand the mechanism by which the individual isoforms regulate energy homeostasis and behavior.

  2. Fumonisin B(1): a neurotoxic mycotoxin.

    PubMed

    Domijan, Ana-Marija

    2012-12-01

    Fumonisin B(1) (FB(1)) is a mycotoxin produced by Fusarium spp. moulds that contaminate crop, predominantly maize, all around the world. More than 15 types of fumonisins have been indentified so far, but FB(1) is the most abundant and toxicologically the most significant one. FB(1) has a wide range of toxic effects, depending on animal species. In horses FB(1) causes equine leukoencephalomalacia (ELEM), in pigs pulmonary oedema and in experimental rodents nephrotoxicity and hepatotoxicity. In humans exposure to FB(1) is linked with higher incidence of primary liver cancer and oesophageal cancer, which are frequent in certain regions of the world (such as Transkei region in South Africa) where maize is staple food. The occurrence of neural tube defect in children in some countries of Central America (such as Mexico and Honduras) is connected with the consumption of FB(1)-contaminated maize-based food. However, possible involvement of FB(1) in the development of human diseases is not clear. Nevertheless, the International Agency for Research on Cancer (IARC) has classified FB(1) as a possible carcinogen to humans (group 2B). FB(1) is a causative agent of ELEM, a brain disorder in equines, indicating that brain is a target organ of FB(1) toxicity. Several studies on experimental animals or on cell cultures of neural origin have established that FB(1) has a neurodegenerative potential, although the mechanism of its neurotoxicity is still vague. The aim of this article is to give an overview of available literature on FB(1) neurotoxicity and involved mechanisms, and to offer a new perspective for future studies.

  3. PDGF enhances IRES-mediated translation of Laminin B1 by cytoplasmic accumulation of La during epithelial to mesenchymal transition.

    PubMed

    Petz, Michaela; Them, Nicole C C; Huber, Heidemarie; Mikulits, Wolfgang

    2012-10-01

    The extracellular matrix protein Laminin B1 (LamB1) regulates tumor cell migration and invasion. Carcinoma cells acquire invasive properties by epithelial to mesenchymal transition (EMT), which is a fundamental step in dissemination of metastatic cells from the primary tumor. Recently, we showed that enhanced translation of LamB1 upon EMT of malignant hepatocytes is mediated by an internal ribosome entry site (IRES). We demonstrated that the IRES transacting factor La binds the minimal IRES motif and positively modulates IRES activity of LamB1. Here, we show that platelet-derived growth factor (PDGF) enhances IRES activity of LamB1 by the increasing cytoplasmic localization of La during EMT. Accordingly, cells expressing dominant negative PDGF receptor display reduced cytoplasmic accumulation of La and show no elevation of IRES activity or endogenous LamB1 levels after stimulation with PDGF. Furthermore, La-mediated regulation of LamB1 IRES activity predominantly depends on MAPK/ERK signaling downstream of PDGF. Notably, LamB1 expression is not significantly downregulated by the impairment of the translation initiation factor eIF4E. In vivo, knockdown of La associated with decreased LamB1 expression and reduced tumor growth. Together, these data suggest that PDGF is required for the cytoplasmic accumulation of La that triggers IRES-dependent translation of LamB1 during EMT.

  4. Antigen-specific memory in B-1a and its relationship to natural immunity.

    PubMed

    Yang, Yang; Ghosn, Eliver Eid Bou; Cole, Leah E; Obukhanych, Tetyana V; Sadate-Ngatchou, Patricia; Vogel, Stefanie N; Herzenberg, Leonard A; Herzenberg, Leonore A

    2012-04-03

    In the companion article by Yang and colleagues [Yang Y, et al. (2012) Proc Natl Acad Sci USA, 109, 10.1073/pnas.1121631109], we have shown that priming with glycolipid (FtL) from Francisella tularensis live-vaccine strain (i) induces FtL-specific B-1a to produce robust primary responses (IgM >IgG); (ii) establishes persistent long-term production of serum IgM and IgG anti-FtL at natural antibody levels; and (iii) elicits FtL-specific B-1a memory cells that arise in spleen but rapidly migrate to the peritoneal cavity, where they persist indefinitely but divide only rarely. Here, we show that FtL rechallenge alone induces these PerC B-1a memory cells to divide extensively and to express a unique activation signature. However, FtL rechallenge in the context of a Toll-like receptor 4 agonist-stimulated inflammatory response readily induces these memory cells to migrate to spleen and initiate production of dominant IgM anti-FtL secondary responses. Thus, studies here reveal unique mechanisms that govern B-1a memory development and expression, and introduce B-1a memory as an active participant in immune defenses. In addition, at a practical level, these studies suggest previously unexplored vaccination strategies for pathogen-associated antigens that target the B-1a repertoire.

  5. SH2B1beta adaptor is a key enhancer of RET tyrosine kinase signaling.

    PubMed

    Donatello, S; Fiorino, A; Degl'Innocenti, D; Alberti, L; Miranda, C; Gorla, L; Bongarzone, I; Rizzetti, M G; Pierotti, M A; Borrello, M G

    2007-10-04

    The RET gene encodes two main isoforms of a receptor tyrosine kinase (RTK) implicated in various human diseases. Activating germ-line point mutations are responsible for multiple endocrine neoplasia type 2-associated medullary thyroid carcinomas, inactivating germ-line mutations for Hirschsprung's disease, while somatic rearrangements (RET/PTCs) are specific to papillary thyroid carcinomas. SH2B1beta, a member of the SH2B adaptors family, and binding partner for several RTKs, has been recently described to interact with proto-RET. Here, we show that both RET isoforms and its oncogenic derivatives bind to SH2B1beta through the SRC homology 2 (SH2) domain and a kinase activity-dependent mechanism. As a result, RET phosphorylates SH2B1beta, which in turn enhances its autophosphorylation, kinase activity, and downstream signaling. RET tyrosine residues 905 and 981 are important determinants for functional binding of the adaptor, as removal of both autophosphorylation sites displaces its recruitment. Binding of SH2B1beta appears to protect RET from dephosphorylation by protein tyrosine phosphatases, and might represent a likely mechanism contributing to its upregulation. Thus, overexpression of SH2B1beta, by enhancing phosphorylation/activation of RET transducers, potentiates the cellular differentiation and the neoplastic transformation thereby induced, and counteracts the action of RET inhibitors. Overall, our results identify SH2B1beta as a key enhancer of RET physiologic and pathologic activities.

  6. 26 CFR 1.367(b)-1 - Other transfers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 4 2010-04-01 2010-04-01 false Other transfers. 1.367(b)-1 Section 1.367(b)-1...) INCOME TAXES Effects on Corporation § 1.367(b)-1 Other transfers. (a) Scope. The regulations promulgated... earnings and profits, basis of stock or securities, basis of assets, or other relevant tax attributes....

  7. 26 CFR 1.267(b)-1 - Relationships.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 3 2010-04-01 2010-04-01 false Relationships. 1.267(b)-1 Section 1.267(b)-1...) INCOME TAXES Items Not Deductible § 1.267(b)-1 Relationships. (a) In general. (1) The persons referred to... partnership separately. Therefore, if the other person and a partner are within any one of the...

  8. 26 CFR 1.7702B-1 - Consumer protection provisions.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 13 2011-04-01 2011-04-01 false Consumer protection provisions. 1.7702B-1 Section 1.7702B-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) General Actuarial Valuations § 1.7702B-1 Consumer...

  9. 26 CFR 31.3306(b)-1 - Wages.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 15 2010-04-01 2010-04-01 false Wages. 31.3306(b)-1 Section 31.3306(b)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) EMPLOYMENT TAXES AND... Unemployment Tax Act (Chapter 23, Internal Revenue Code of 1954) § 31.3306(b)-1 Wages. (a) Applicable law...

  10. 40 CFR Figure B-1 to Subpart B of... - Example

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 6 2014-07-01 2014-07-01 false Example B Figure B-1 to Subpart B of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED... of Automated Methods for SO2, CO, O3, and NO2 Pt. 53, Subpt. B, Fig. B-1 Figure B-1 to Subpart B...

  11. 40 CFR Figure B-1 to Subpart B of... - Example

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 6 2012-07-01 2012-07-01 false Example B Figure B-1 to Subpart B of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED... of Automated Methods for SO2, CO, O3, and NO2 Pt. 53, Subpt. B, Fig. B-1 Figure B-1 to Subpart B...

  12. 40 CFR Figure B-1 to Subpart B of... - Example

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 6 2013-07-01 2013-07-01 false Example B Figure B-1 to Subpart B of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED... of Automated Methods for SO2, CO, O3, and NO2 Pt. 53, Subpt. B, Fig. B-1 Figure B-1 to Subpart B...

  13. Effects of forskolin analogs, phosphodiesterase inhibitors and 8-bromo cyclic AMP on plasma exudations induced with bradykinin and prostaglandin E/sub 1/ in rat skin

    SciTech Connect

    Sugio, K.; Daly, J.W.

    1984-01-09

    The effects of forskolin analogs, phosphodiesterase inhibitors and 8-bromo cyclic AMP on plasma exudations induced with bradykinin and prostaglandin E/sub 1/ in rat skin were investigated using (/sup 125/I) bovine serum albumin (/sup 125/I-BSA). Forskolin, forskolin 7-ethyl carbonate and 7-desacetylforskolin, which are potent activators of adenylate cyclase, greatly potentiated the bradykinin-induced plasma exudation and inhibited the prostaglandin E/sub 1/-induced response. The phosphodiesterase inhibitors, ZK 627ll, dipyridamole, HL 725, and 3-isobutyl-1-methylxanthine potentiated the bradykinin-induced plasma exudation and inhibited and prostaglandin E/sub 1/-induced response. 8-Bromo cyclic AMP in the doses of 0.01 to 1 ..mu..g potentiated the bradykinin-induced plasma exudation, but had no effect at doses of 10 and 100 ..mu..g. 8-bromo cyclic AMP at all doses significantly inhibited the prostaglandin E/sub 1/-induced response. The results suggest that the effects of forskolin and its analogs on plasma exudations induced with bradykinin and prostaglandin E/sub 1/ in rat skin derive from activation of cyclic AMP-generating systems.

  14. Bradykinin antagonists and thiazolidinone derivatives as new potential anti-cancer compounds.

    PubMed

    Avdieiev, Stanislav; Gera, Lajos; Havrylyuk, Dmytro; Hodges, Robert S; Lesyk, Roman; Ribrag, Vincent; Vassetzky, Yegor; Kavsan, Vadym

    2014-08-01

    Glioblastoma (GB), the most aggressive brain tumour, and mantle cell lymphoma (MCL), a rare but very aggressive type of lymphoma, are highly resistant to chemotherapy. GB and MCL chemotherapy gives very modest results, the vast majority of patients experience recurrent disease. To find out the new treatment modality for drug-resistant GB and MCL cells, combining of bradykinin (BK) antagonists with conventional temozolomide (TMZ) treatment, and screening of thiazolidinones derivatives were the main objectives of this work. As it was revealed here, BKM-570 was the lead compound among BK antagonists under investigation (IC50 was 3.3 μM) in human GB cells. It strongly suppressed extracellular signal-regulated kinases 1/2 (ERK1/2) and protein kinase B (AKT) phosphorylation. BK antagonists did not decrease the viability of MCL cells, thus showing the cell-specific mode, while thiazolidinone derivatives, a novel group of promising anti-tumour compounds inhibited proliferation of MCL cells: IC₅₀ of ID 4526 and ID 4527 compounds were 0.27 μM and 0.16 μM, correspondingly. However, single agents are often not effective in clinic due to activation of collateral pathways in tumour cells. We demonstrated a strong synergistic effect after combinatorial treatment by BKM-570 together with TMZ that drastically increased cytotoxic action of this drug in rat and human glioma cells. Small proportion of cells was still viable after such treatment that could be explained by presence of TMZ-resistant cells in the population. It is possible to expect that the combined therapy aimed simultaneously at different elements of tumourigenesis will be more effective with lower drug concentrations than the first-line drug temozolomide used alone in clinics.

  15. Bradykinin decreases K+ and increases Cl− conductances in vagal afferent neurones of the guinea pig

    PubMed Central

    Oh, Eun Joo; Weinreich, Daniel

    2004-01-01

    Bradykinin (BK) is an inflammatory mediator that can excite and sensitize primary afferent neurones. The nature of the ionic channels underlying the excitatory actions of BK is still incompletely understood. Using whole-cell patch-clamp recording from acutely dissociated nodose ganglion neurones (NGNs) we have examined the ionic mechanism responsible for BK's excitatory effect. Bath-applied BK (0.1 μm) depolarized the membrane potential (29 ± 3.1 mV, n = 7), evoked action potentials, and induced an inward ionic current (IBK) with two distinctive membrane conductances (gm). Initially, gm decreased; the ionic current associated with this gm had a reversal potential (Erev) value of −87 ± 1.1 mV (n = 26), a value close to EK (−89 mV). Subsequently, gm increased; the ionic current associated with this gm had an estimated Erev of 49 ± 4.3 mV (n = 23). When the second component was isolated from the first component, by replacing [K+]o with Cs+, Erev was 20 ± 4.7 mV (n = 10). Replacing external NaCl with NMDG-Cl or choline-Cl, or reducing [Ca2+]o did not significantly diminish IBK. After replacing external NaCl with sodium isethionate, Erev for the second component shifted to 56 ± 8.8 mV (n = 4), a value close to the ECl (66 mV). The second component was inhibited by intracellular BAPTA or by bath application of niflumic acid (100 μm), a Ca2+-activated Cl− channel blocker. These results suggest that the first and second components of IBK are produced by a decrease in K+ conductance and an increase in Ca2+-activated Cl− conductance, respectively. The BK-evoked Cl− conductance in NGNs may be the first demonstration of an inflammatory mediator exciting primary afferents via an anion channel. PMID:15169850

  16. Effect of captopril and the bradykinin-PKC pathway on ROS production in type 1 diabetic rats.

    PubMed

    Rodrigues de Araujo, Glaucy; Granato de Faria, Karine; Lima, Wanderson Geraldo; Pádua, Bruno da Cruz; Rossoni, Joamyr Victor; Souza, Aline Arlindo; Chianca-Júnior, Deoclecio; Silva, Marcelo Eustáquio; Pedrosa, Maria Lucia; Chaves, Miriam Martins; Costa, Daniela Caldeira

    2011-12-01

    The aim of this study was to investigate the possible effects of captopril as a promoter in modulating the oxidant-antioxidant balance in rats with type 1 diabetes, and the influence of protein kinase C (PKC) pathways in the production of reactive oxygen species (ROS) induced by bradykinin in type 1 diabetic rats. This study evaluated the redox status in both the cardiac tissue and at the cellular level (neutrophils). Two concentrations of captopril were utilized: (i) 5 mg·(kg body mass)(-1), which was considered a therapeutic dose; and (ii) 10 mg·(kg body mass)(-1). Body mass, plasma glucose, and serum insulin were evaluated. To investigate the redox status of the cardiac tissue, we analyzed lipid peroxidation, concentration of carbonylated protein, catalase activity, and the concentration of glutathione. For a more accurate assessment of the possible antioxidant effect of captopril, we also analyzed ROS in neutrophils (in vivo), and ROS production induced by bradykinin and the influence of the PKC pathway in this production (in vitro). Our data show that the hearts of diabetic animals have increased oxidative damage, exemplified by the increased concentration of carbonylated protein and thiobarbituric acid reactive substances (TBARS). However, animals treated with captopril at both concentrations showed lower concentrations of carbonylated protein compared with untreated diabetic animals. We found an increase of catalase activity in the heart of diabetic rats, which was reversed by captopril treatment at both of the dosages tested. Our data showed that captopril was able to reduce ROS production in the neutrophils of diabetic rats at a dose of 10 mg captopril·(kg body mass)(-1). However, the antioxidant effect of captopril is independent of bradykinin. Diabetes induces oxidative stress, and these results suggest that captopril has an antioxidant effect and can modulate the production of ROS in circulating neutrophils.

  17. Reactive Oxygen Species-Dependent c-Fos/Activator Protein 1 Induction Upregulates Heme Oxygenase-1 Expression by Bradykinin in Brain Astrocytes.

    PubMed

    Hsieh, Hsi-Lung; Wang, Hui-Hsin; Wu, Cheng-Ying; Yang, Chuen-Mao

    2010-12-15

    Heme oxygenase-1 (HO-1) plays a crucial role in tissue pathological changes such as brain injuries. Our previous studies have demonstrated that bradykinin (BK) induces the expression of several inflammatory proteins, including matrix metalloproteinase-9 and COX-2, via mitogen-activated protein kinases and nuclear factor-κB (NF-κB) in rat brain astrocytes (RBA-1). However, the molecular mechanisms underlying BK-induced HO-1 expression in RBA-1 cells remain poorly defined. Here we demonstrated that BK induced HO-1 expression and enzymatic activity via a B(2) BK receptor-activated reactive oxygen species (ROS)-dependent signaling pathway. NADPH oxidase (Nox)-dependent ROS generation led to activation of extracellular signal-regulated kinase 1/2 (ERK1/2) and c-Jun-N-terminal kinase (JNK) and then activated the downstream molecules NF-κB and c-Jun, respectively. The c-Fos, an activator protein 1 (AP-1) subunit, was upregulated by activation of NF-κB and c-Jun, which bound to HO-1 promoter and thereby turned on transcription of HO-1 gene. The rat HO-1 promoter containing a putative AP-1 cis-binding site was identified as a crucial domain linking to BK action. Taken together, these results suggested that in RBA-1 cells, activation of ERK/NF-κB and JNK/c-Jun cascades by a Nox/ROS-dependent event enhancing c-Fos/AP-1 activity is essential for HO-1 upregulation and activation induced by BK. Moreover, ROS-dependent NF-E2-related factor 2 activation also contributes to HO-1 induction by BK in astrocytes.

  18. Effects of aflatoxin B(1) and fumonisin B(1) on blood biochemical parameters in broilers.

    PubMed

    Tessari, Eliana N C; Kobashigawa, Estela; Cardoso, Ana Lúcia S P; Ledoux, David R; Rottinghaus, George E; Oliveira, Carlos A F

    2010-04-01

    The individual and combined effects of dietary aflatoxin B(1 )(AFB(1)) and fumonisin B(1) (FB(1)) on liver pathology, serum levels of aspartate amino-transferase (AST) and plasma total protein (TP) of broilers were evaluated from 8 to 41 days of age. Dietary treatments included a 3 × 3 factorial arrangement with three levels of AFB(1 )(0, 50 and 200 μg AFB(1)/kg), and three levels of FB(1 )(0, 50 and 200 mg FB(1)/kg). At 33 days post feeding, with the exception of birds fed 50 mg FB(1 )only, concentrations of AST were higher (p < 0.05) in all other treatment groups when compared with controls. Plasma TP was lower (p < 0.05) at six days post feeding in groups fed 200 μg AFB(1)/kg alone or in combination with FB(1). At day 33 days post feeding, with the exception of birds fed the highest combination of AFB(1 )and FB(1 )which had higher plasma TP than control birds(, )plasma TP of birds fed other dietary treatments were similar to controls. Broilers receiving the highest levels of AFB(1) and FB(1) had bile duct proliferation and trabecular disorder in liver samples. AFB(1) singly or in combination with FB at the levels studied, caused liver damage and an increase in serum levels of AST.

  19. Modulation of the cell membrane expression of the kininogens regulates the rate of bradykinin delivery to cells.

    PubMed

    Schmaier, A H

    1992-01-01

    The kininogens were first recognized as the parent molecules for bradykinin. Their relative physiologic importance in plasma hemostasis and fibrinolysis and tissue cysteine protease inhibition has not been clarifed. Recent studies on the structure and function of the plasma kininogens, their interaction with cells of the intravascular compartment, and clinical investigations on contact system activation have refocused the physiologic importance of these proteins to kinin delivery for the maintance of vasodilatory tone. Kininogen expression on platelets slows the rate of kinin liberation, and kinins upregulate kininogen expression on endothelial cells. Regulation of kinin delivery by influencing kininogen expression may provide for new agents to manipulate blood pressure.

  20. Chronic Moderate Alcohol Intakes Accelerate SR-B1 Mediated Reverse Cholesterol Transport

    PubMed Central

    Li, Menghua; Diao, Yan; Liu, Ying; Huang, Hui; Li, Yanze; Tan, Peizhu; Liang, Huan; He, Qi; Nie, Junhui; Dong, Xingli; Wang, Yang; Zhou, Lingyun; Gao, Xu

    2016-01-01

    Cholesterol is essential for all animal life. However, a high level of cholesterol in the body is strongly associated with the progression of various severe diseases. In our study, the potential involvement of alcohol in the regulation of high density lipoprotein (HDL) receptor scavenger receptor class B and type I (SR-B1)-mediated reverse cholesterol transport was investigated. We separated male C57BL/6 mice into four diets: control, alcohol, Control + HC and alcohol + HC. The SR-B1 level and 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate- high- density lipoprotein (DiI-HDL) uptake were also measured in AML12 cells and HL7702 cells treated with alcohol. The control + HC diet led to increased hepatic triglyceride and cholesterol levels while alcohol + HC led no significant change. Compared with that of the control group, the SR-B1 mRNA level was elevated by 27.1% (P < 0.05), 123.8% (P < 0.001) and 343.6% (P < 0.001) in the alcohol, control + HC and alcohol + HC groups, respectively. In AML12 and HL7702 cells, SR-B1 level and DiI-HDL uptake were repressed by SR-B1 siRNA or GW9662. However, these effects were reversed through alcohol treatment. These data suggest that a moderate amount of alcohol plays a novel role in reverse cholesterol transport, mainly mediated by PPARγ and SR-B1. PMID:27618957

  1. New function of the adaptor protein SH2B1 in brain-derived neurotrophic factor-induced neurite outgrowth.

    PubMed

    Shih, Chien-Hung; Chen, Chien-Jen; Chen, Linyi

    2013-01-01

    Neurite outgrowth is an essential process for the establishment of the nervous system. Brain-derived neurotrophic factor (BDNF) binds to its receptor TrkB and regulates axonal and dendritic morphology of neurons through signal transduction and gene expression. SH2B1 is a signaling adaptor protein that regulates cellular signaling in various physiological processes. The purpose of this study is to investigate the role of SH2B1 in the development of the central nervous system. In this study, we show that knocking down SH2B1 reduces neurite formation of cortical neurons whereas overexpression of SH2B1β promotes the development of hippocampal neurons. We further demonstrate that SH2B1β promotes BDNF-induced neurite outgrowth and signaling using the established PC12 cells stably expressing TrkB, SH2B1β or SH2B1β mutants. Our data indicate that overexpressing SH2B1β enhances BDNF-induced MEK-ERK1/2, and PI3K-AKT signaling pathways. Inhibition of MEK-ERK1/2 and PI3K-AKT pathways by specific inhibitors suggest that these two pathways are required for SH2B1β-promoted BDNF-induced neurite outgrowth. Moreover, SH2B1β enhances BDNF-stimulated phosphorylation of signal transducer and activator of transcription 3 at serine 727. Finally, our data indicate that the SH2 domain and tyrosine phosphorylation of SH2B1β contribute to BDNF-induced signaling pathways and neurite outgrowth. Taken together, these findings demonstrate that SH2B1β promotes BDNF-induced neurite outgrowth through enhancing pathways involved MEK-ERK1/2 and PI3K-AKT.

  2. SH2B1 enhances leptin signaling by both Janus kinase 2 Tyr813 phosphorylation-dependent and -independent mechanisms.

    PubMed

    Li, Zhiqin; Zhou, Yingjiang; Carter-Su, Christin; Myers, Martin G; Rui, Liangyou

    2007-09-01

    Leptin controls body weight by activating its long form receptor (LEPRb). LEPRb binds to Janus kinase 2 (JAK2), a cytoplasmic tyrosine kinase that mediates leptin signaling. We previously reported that genetic deletion of SH2B1 (previously known as SH2-B), a JAK2-binding protein, results in severe leptin-resistant and obese phenotypes, indicating that SH2B1 is a key endogenous positive regulator of leptin sensitivity. Here we show that SH2B1 regulates leptin signaling by multiple mechanisms. In the absence of leptin, SH2B1 constitutively bound, via its non-SH2 domain region(s), to non-tyrosyl-phosphorylated JAK2, and inhibited JAK2. Leptin stimulated JAK2 phosphorylation on Tyr(813), which subsequently bound to the SH2 domain of SH2B1. Binding of the SH2 domain of SH2B1 to phospho-Tyr(813) in JAK2 enhanced leptin induction of JAK2 activity. JAK2 was required for leptin-stimulated phosphorylation of insulin receptor substrate 1 (IRS1), an upstream activator of the phosphatidylinositol 3-kinase pathway. Overexpression of SH2B1 enhanced both JAK2- and JAK2(Y813F)-mediated tyrosine phosphorylation of IRS1 in response to leptin, even though SH2B1 did not enhance JAK2(Y813F) activation. Leptin promoted the interaction of SH2B1 with IRS1. These data suggest that constitutive SH2B1-JAK2 interaction, mediated by the non-SH2 domain region(s) of SH2B1 and the non-Tyr(813) region(s) in JAK2, increases the local concentration of SH2B1 close to JAK2 and inhibits JAK2 activity. Leptin-stimulated SH2B1-JAK2 interaction, mediated by the SH2 domain of SH2B1 and phospho-Tyr(813) in JAK2, promotes JAK2 activation, thus globally enhancing leptin signaling. SH2B1-IRS1 interaction facilitates IRS1 phosphorylation by recruiting IRS1 to JAK2 and/or by protecting IRS1 from dephosphorylation, thus specifically enhancing leptin stimulation of the phosphatidylinositol 3-kinase pathway.

  3. Isolated rat stomach ECL cells generate prostaglandin E(2) in response to interleukin-1 beta, tumor necrosis factor-alpha and bradykinin.

    PubMed

    Lindström, E; Lerner, U H; Håkanson, R

    2001-03-30

    The ECL cells control parietal cells by releasing histamine in their immediate vicinity. Gastrin and pituitary adenylate cyclase-activating peptide (PACAP) stimulate histamine secretion from isolated ECL cells, while somatostatin and galanin inhibit stimulated secretion. Prostaglandin E2 and related prostaglandins likewise suppress ECL-cell histamine secretion. Conceivably, that is how they inhibit acid secretion. In the present study, we examined if prostaglandin E2 can be generated by isolated ECL cells. Rat stomach ECL cells were purified (>90% purity) by counterflow elutriation and gradient centrifugation and cultured for 48 h. ECL cell stimulants (gastrin and PACAP) and inflammatory agents (interleukin-1 beta, tumor necrosis factor-alpha and bradykinin) were tested for their ability to induce prostaglandin E2 accumulation (24-h incubation), measured by radioimmunoassay. Gastrin and PACAP did not affect prostaglandin E2 accumulation but interleukin-1 beta (300 pg/ml), tumor necrosis factor-alpha (10 ng/ml) and bradykinin (1 microM) induced a 2- to 3-fold increase in the amount of prostaglandin E2 accumulated. While the combination of interleukin-1 beta and bradykinin induced a 9-fold increase, the combination interleukin-1 beta+tumor necrosis factor-alpha and bradykinin + tumor necrosis factor-alpha induced additive effects only. The combination of interleukin-1 beta + tumor necrosis factor-alpha + bradykinin did not induce a greater effect than interleukin-1 beta + bradykinin. The effect of interleukin-1 beta + bradykinin was abolished by adding 10 nM hydrocortisone (suppressing phospholipase A2 and cyclooxygenase) or 1 microM indomethacin (inhibiting cyclooxygenase). Incubating ECL cells in the presence of interleukin-1 beta+bradykinin for 24 h reduced their ability to secrete histamine in response to gastrin. The inhibitory effect was reversed by 1 microM indomethacin. Also, increasing the concentrations of hydrocortisone in the medium resulted in an

  4. SH2B1 orchestrates signaling events to filopodium formation during neurite outgrowth.

    PubMed

    Chen, Kuan-Wei; Chang, Yu-Jung; Chen, Linyi

    2015-01-01

    Morphogenesis during development is fundamental to the differentiation of several cell types. As neurite outgrowth marks neuritogenesis, formation of filopodia precede the formation of dendrites and axons. While the structure of filopodia is well-known, the initiation of filopodia during neurite outgrowth is not clear. SH2B1 is known to promote neurite outgrowth of PC12 cells, hippocampal and cortical neurons. As a signaling adaptor protein, SH2B1 interacts with several neurotrophin receptors, and regulates signaling as well as gene expression. Our recent findings suggest that SH2B1 can be recruited to the plasma membrane and F-actin fractions by IRSp53. IRSp53 bends plasma membrane and facilitates actin bundling to set the stage for filopodium formation. We further demonstrate that SH2B1-IRSp53 complexes enhance the formation of filopodia, dendrites and dendritic branches of hippocampal and cortical neurons. While the molecular mechanism underlying filopodium initiation is not clear, we propose that SH2B1-neurotrophin interacting sites may mark the putative sites of filopodium initiation.

  5. SH2B1 orchestrates signaling events to filopodium formation during neurite outgrowth

    PubMed Central

    Chen, Kuan-Wei; Chang, Yu-Jung; Chen, Linyi

    2015-01-01

    Morphogenesis during development is fundamental to the differentiation of several cell types. As neurite outgrowth marks neuritogenesis, formation of filopodia precede the formation of dendrites and axons. While the structure of filopodia is well-known, the initiation of filopodia during neurite outgrowth is not clear. SH2B1 is known to promote neurite outgrowth of PC12 cells, hippocampal and cortical neurons. As a signaling adaptor protein, SH2B1 interacts with several neurotrophin receptors, and regulates signaling as well as gene expression. Our recent findings suggest that SH2B1 can be recruited to the plasma membrane and F-actin fractions by IRSp53. IRSp53 bends plasma membrane and facilitates actin bundling to set the stage for filopodium formation. We further demonstrate that SH2B1-IRSp53 complexes enhance the formation of filopodia, dendrites and dendritic branches of hippocampal and cortical neurons. While the molecular mechanism underlying filopodium initiation is not clear, we propose that SH2B1-neurotrophin interacting sites may mark the putative sites of filopodium initiation. PMID:26479731

  6. SH2B1 (SH2-B) and JAK2: a multifunctional adaptor protein and kinase made for each other.

    PubMed

    Maures, Travis J; Kurzer, Jason H; Carter-Su, Christin

    2007-01-01

    Src homology 2 (SH2) B adaptor protein 1 (SH2B1; originally named SH2-B) is a member of a family of adaptor proteins that influences a variety of signaling pathways mediated by Janus kinase (JAK) and receptor tyrosine kinases. Although SH2B1 performs classical adaptor functions, such as recruitment of specific proteins to activated receptors, it also demonstrates a unique ability to enhance the kinase activity of the cytokine receptor-associated tyrosine kinase JAK2, as well as that of several receptor tyrosine kinases. SH2B1 is also among a small number of adaptor proteins shown to undergo nucleocytoplasmic shuttling, although its exact role within the nucleus is not yet clear. Deletion of the SH2B1 gene results in severe obesity and both leptin and insulin resistance, as well as infertility, which might be a consequence of resistance to insulin-like growth factor I. Thus, knockout mice support a role for SH2B1 as a positive regulator of JAK2 signaling pathways initiated by leptin, as well as of pathways initiated by insulin and, potentially, by insulin-like growth factor I.

  7. Genetic variation of Cytochrome P450 1B1 (CYP1B1) and risk of breast cancer among Polish women.

    PubMed

    Gaudet, Mia M; Chanock, Stephen; Lissowska, Jolanta; Berndt, Sonja I; Yang, Xiaohong Rose; Peplonska, Beata; Brinton, Louise A; Welch, Robert; Yeager, Meredith; Bardin-Mikolajczak, Alicja; Sherman, Mark E; Sutter, Thomas R; Garcia-Closas, Montserrat

    2006-08-01

    Four single nucleotide polymorphisms (SNPs) in CYP1B1 (Ex2 + 143 C > G, Ex2 + 356 G > T, Ex3 + 251 G > C, Ex3 + 315 A > G) cause amino acid changes (R48G, A119S, L432V and N453S, respectively) and are associated with increased formation of catechol estrogens; however, epidemiologic evidence only weakly supports an association between these variants and breast cancer risk. Because genetic variability conferring increased susceptibility could exist beyond these putative functional variants, we comprehensively examined the common genetic variability within CYP1B1. A total of eight haplotype-tagging (ht)SNPs (including Ex3 + 315 A > G), in addition to two putatively functional SNPs (Ex2 + 143 C > G and Ex3 + 251 G > C), were selected and genotyped in a large case-control study of Polish women (1995 cases and 2296 controls). Haplotypes were estimated using the expectation-maximization algorithm, and overall differences in the haplotype distribution between cases and controls were assessed using a global score test. We also evaluated levels of tumor CYP1B1 protein expression in a subset of 841 cases by immunohistochemistry, and their association with genetic variants. In the Polish population, we observed two linkage disequilibrium (LD)-defined blocks. Neither haplotypes (global P-value of 0.99 and 0.67 for each block of LD, respectively), nor individual SNPs (including three putatively functional SNPs) were associated with breast cancer risk. CYP1B1 was expressed in most tumor tissues (98%), and the level of expression was not related to the studied genetic variants. We found little evidence for modification of the estimated effect of haplotypes or individual SNPs by age, family history of breast cancer, or tumor hormone receptor status. The present study provides strong evidence against the existence of a substantial overall association between common genetic variation in CYP1B1 and breast cancer risk.

  8. Quinazoline derivatives as selective CYP1B1 inhibitors.

    PubMed

    Mohd Siddique, Mohd Usman; McCann, Glen J P; Sonawane, Vinay R; Horley, Neill; Gatchie, Linda; Joshi, Prashant; Bharate, Sandip B; Jayaprakash, Venkatesan; Sinha, Barij N; Chaudhuri, Bhabatosh

    2017-04-21

    CYP1B1 is implicated to have a role in the development of breast, ovarian, renal, skin and lung carcinomas. It has been suggested that identification of potent and specific CYP1B1 inhibitors can lead to a novel treatment of cancer. Flavonoids have a compact rigid skeleton which fit precisely within the binding cavity of CYP1B1. Systematic isosteric replacement of flavonoid 'O' atom with 'N' atom led to the prediction that a 'quinazoline' scaffold could be the basis for designing potential CYP1B1 inhibitors. A total of 20 quinazoline analogs were synthesized and screened for CYP1B1 and CYP1A1 inhibition in Sacchrosomes™. IC50 determinations of six compounds with capability of inhibiting CYP1B1 identified quinazolines 5c and 5h as the best candidates for CYP1B1 inhibition, with IC50 values in the nM range. Further selectivity studies with homologous CYPs, belonging to the CYP1, CYP2 and CYP3 family of enzymes, showed that the compounds are likely to be free from critical drug-drug interaction liability. Molecular modelling studies were performed to rationalize the observed enzymatic inhibitions. Further biological studies in live yeast and human cells, harboring CYP1A1 and CYP1B1 enzymes, have illustrated the most potent compounds' cellular permeability and capability of potently inhibiting CYP1B1 enzyme expressed within live cells.

  9. Homology modeling, vasorelaxant and bradykinin-potentiating activities of a novel hypotensin found in the scorpion venom from Tityus stigmurus.

    PubMed

    Machado, Richele J A; Junior, Leônidas G M; Monteiro, Norberto K V; Silva-Júnior, Arnóbio A; Portaro, Fernanda C V; Barbosa, Euzébio G; Braga, Valdir A; Fernandes-Pedrosa, Matheus F

    2015-07-01

    In a recent work by our group involving a transcriptomics approach applied to the venom glands from Tityus stigmurus we identified a new family of peptides called Hypotensins (TSTI0006C) (Almeida et al., 2012). The cluster TSTI0006C was analyzed in the main 25 amino acid residues and named T. stigmurus Hypotensin (TistH), showing a molecular mass of 2.7 kDa, an absence of cysteines and the presence of two C-terminal proline residues, which are a bradykinin-potentiating peptide (BPP) signature. Here, we describe the homology modeling of the three-dimensional structure of TistH. In addition, we evaluated the cardiovascular effects elicited by TistH in normotensive rats. Firstly, TistH showed no cytotoxic effect on horse erythrocyte. Furthermore, in normotensive rats TistH was able to potentiate the hypotensive action of bradykinin (BK) and induced a vasorelaxant effect in mesenteric artery rings by endothelium-dependent release of nitric oxide (NO) and demonstrated independent inhibition of angiotensin converting enzyme (ACE). Our data can contribute to a better understanding of the structural and functional characteristics of TistH and suggest its potential use in cardiovascular diseases.

  10. Surface- and tip-enhanced Raman scattering of bradykinin onto the colloidal suspended Ag surface.

    PubMed

    Swiech, D; Ozaki, Y; Kim, Y; Proniewicz, E

    2015-07-14

    In this paper, surface- (SERS) and tip-enhanced Raman scattering (TERS) techniques were used to determine the adsorption mode of bradykinin (BK), a small peptide implicated in, for example, carcinoma growth, onto colloidal suspended Ag surfaces under various environmental conditions, including: peptide concentrations (10(-5)-10(-7) M), excitation wavelengths (514.5 and 785.0 nm), and pH of aqueous sol solutions (from pH = 3 to pH = 11). The metal surface plasmon and rheology of the colloidal suspended Ag surface were explored by ultraviolet-visible (UV-Vis) spectroscopy and atomic force/scanning electron microscopy (AFM/SEM). The SERS results indicated that the peptide concentration of 10(-5) M was the optimal peptide concentration for monolayer colloidal coverage. The Phe(5/8) and Arg(9) residues of BK generally participated in the interactions with colloidal suspended Ag surfaces. The amide group appeared to be arranged in the same manner to the Ag surface in the pH range of 3 to 11. At acidic pH of the solution (pH = 3 to 5), the BK -COO(-) terminal group binds to the Ag surface as a bidentate (at pH = 3) or monodentate (at pH = 5) chelating ligand. At pH = 11, the imino group of Arg(9), probably due to its -C[double bond, length as m-dash]N(⊕)H2 protonation state, was not involved in the interaction with Ag. The reduction in the solution alkalinity (pH = 9) produced the deprotonation of the -C=N(⊕)H2 group followed by group rearrangement in a way favoring the interaction between the lone electron pair on N and Ag. The TERS studies confirmed the proposed, on the basis of SERS, behavior of BK onto the colloidal suspended Ag at pH = 7 and showed that in different points of the colloidal suspended Ag surface the same peptide fragments approximately having the same orientations with respect to this surface interact with it.

  11. Loss of endophilin-B1 exacerbates Alzheimer's disease pathology.

    PubMed

    Wang, David B; Kinoshita, Yoshito; Kinoshita, Chizuru; Uo, Takuma; Sopher, Bryce L; Cudaback, Eiron; Keene, C Dirk; Bilousova, Tina; Gylys, Karen; Case, Amanda; Jayadev, Suman; Wang, Hong-Gang; Garden, Gwenn A; Morrison, Richard S

    2015-07-01

    Endophilin-B1, also known as Bax-interacting factor 1 (Bif-1, and encoded by SH3GLB1), is a multifunctional protein involved in apoptosis, autophagy and mitochondrial function. We recently described a unique neuroprotective role for neuron-specific alternatively spliced isoforms of endophilin-B1. To examine whether endophilin-B1-mediated neuroprotection could be a novel therapeutic target for Alzheimer's disease we used a double mutant amyloid precursor protein and presenilin 1 (APPswe/PSEN1dE9) mouse model of Alzheimer's disease and observed that expression of neuron-specific endophilin-B1 isoforms declined with disease progression. To determine if this reduction in endophilin-B1 has a functional role in Alzheimer's disease pathogenesis, we crossed endophilin-B1(-/-) mice with APPswe/PSEN1dE9 mice. Deletion of endophilin-B1 accelerated disease onset and progression in 6-month-old APPswe/PSEN1dE9/endophilin-B1(-/-) mice, which showed more plaques, astrogliosis, synaptic degeneration, cognitive impairment and mortality than APPswe/PSEN1dE9 mice. In mouse primary cortical neuron cultures, overexpression of neuron-specific endophilin-B1 isoforms protected against amyloid-β-induced apoptosis and mitochondrial dysfunction. Additionally, protein and mRNA levels of neuron-specific endophilin-B1 isoforms were also selectively decreased in the cerebral cortex and in the synaptic compartment of patients with Alzheimer's disease. Flow sorting of synaptosomes from patients with Alzheimer's disease demonstrated a negative correlation between amyloid-β and endophilin-B1 levels. The importance of endophilin-B1 in neuronal function was further underscored by the development of synaptic degeneration and cognitive and motor impairment in endophilin-B1(-/-) mice by 12 months. Our findings suggest that endophilin-B1 is a key mediator of a feed-forward mechanism of Alzheimer's disease pathogenesis where amyloid-β reduces neuron-specific endophilin-B1, which in turn enhances amyloid

  12. MLL Histone Methylases Regulate Expression of HDLR-SR-B1 in Presence of Estrogen and Control Plasma Cholesterol in Vivo

    PubMed Central

    Ansari, Khairul I.; Kasiri, Sahba; Hussain, Imran; Bobzean, Samara A. Morris; Perrotti, Linda I.

    2013-01-01

    High-density lipoprotein receptors scavenger receptor class B type I [HDLR-SR-B1 (SR-B1)] is a key player in reverse cholesterol transport and maintaining blood cholesterol. We demonstrated that human SR-B1 is transcriptionally activated by 17β-estradiol (E2) in HEPG2 and JAR cells. SR-B1 promoter contains multiple estrogen response elements (ERE half-sites) along with some Sp1 binding sites. Knockdown of estrogen receptor (ER)α and ERβ down-regulated E2-induced SR-B1 expression. ERs were bound to SR-B1 promoter EREs in an E2-dependent manner. Along with ERs, mixed-lineage leukemia (MLL) histone methylases, especially MLL1 and MLL2, play key roles in E2-mediated SR-B1 activation. MLL1 and MLL2 bind to SR-B1 promoter in an E2-dependent manner and control the assembly of transcription pre-initiation complex and RNA polymerase II (RNAPII) recruitment. ERs and MLLs play critical roles in determining the cholesterol uptake by steroidogenic tissues/cells, and their knockdown suppressed the E2-induced cholesterol uptake efficiencies of the cells. Intriguingly, MLL2 knockdown in mice resulted in a 33% increase in plasma cholesterol level and also reduced SR-B1 expression in mice liver, demonstrating its crucial functions in controlling plasma cholesterol in vivo. PMID:23192982

  13. 26 CFR 1.665(b)-1A - Accumulation distributions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Accumulation distributions. 1.665(b)-1A Section... TAX (CONTINUED) INCOME TAXES Treatment of Excess Distributions of Trusts Applicable to Taxable Years Beginning on Or After January 1, 1969 § 1.665(b)-1A Accumulation distributions. (a) In general. (1) For...

  14. 26 CFR 48.4061(b)-1 - Imposition of tax.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 16 2013-04-01 2013-04-01 false Imposition of tax. 48.4061(b)-1 Section 48.4061... EXCISE TAXES MANUFACTURERS AND RETAILERS EXCISE TAXES Motor Vehicles, Tires, Tubes, Tread Rubber, and Taxable Fuel Automotive and Related Items § 48.4061(b)-1 Imposition of tax. (a) In general. Section...

  15. 26 CFR 1.643(b)-1 - Definition of income.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Definition of income. 1.643(b)-1 Section 1.643(b)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX... of subparts A through D, part I, subchapter J, chapter 1 of the Internal Revenue Code, “income,”...

  16. 26 CFR 48.4061(b)-1 - Imposition of tax.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 16 2010-04-01 2010-04-01 true Imposition of tax. 48.4061(b)-1 Section 48.4061(b)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) MISCELLANEOUS EXCISE TAXES MANUFACTURERS AND RETAILERS EXCISE TAXES Motor Vehicles, Tires, Tubes, Tread Rubber,...

  17. 26 CFR 1.168(b)-1 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 2 2013-04-01 2013-04-01 false Definitions. 1.168(b)-1 Section 1.168(b)-1... tangible, depreciable property that is placed in service after December 31, 1986 (or after July 31, 1986, if the taxpayer made an election under section 203(a)(1)(B) of the Tax Reform Act of 1986; 100...

  18. 38 CFR 18b.1 - Scope of rules.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Scope of rules. 18b.1 Section 18b.1 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS (CONTINUED) PRACTICE AND PROCEDURE UNDER TITLE VI OF THE CIVIL RIGHTS ACT OF 1964 AND PART 18 OF THIS CHAPTER General...

  19. 76 FR 38371 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

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  20. 75 FR 42708 - 36(b)(1) Arms Sales Notifications

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    ... of the Secretary 36(b)(1) Arms Sales Notifications AGENCY: Defense Security Cooperation Agency, DoD... 36(b)(1) arms sales notifications to fulfill the requirements of section 155 of Public Law 104-164, dated 21 July 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English, DSCA/DBO/CFM, (703)...

  1. 76 FR 61673 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

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    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  2. 77 FR 46419 - 36(b)(1) Arms Sales Notification

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    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  3. 76 FR 30667 - 36(b)(1) Arms Sales Notification

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    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated 21 July 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  4. 76 FR 68429 - 36(b)(1) Arms Sales Notification

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    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B....

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    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

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    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

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    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B....

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    ... Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B....

  9. 78 FR 26330 - 36(b)(1) Arms Sales Notification

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    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B....

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  12. 75 FR 62767 - 36(b)(1) Arms Sales Notifications

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    ... of the Secretary 36(b)(1) Arms Sales Notifications AGENCY: Defense Security Cooperation Agency, DoD... 36(b)(1) arms sales notifications to fulfill the requirements of section 155 of Public Law 104-164, dated 21 July 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English, DSCA/DBO/CFM, (703)...

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    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

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    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. ] This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B....

  15. 76 FR 77809 - 36(b)(1) Arms Sales Notification

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    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B....

  16. 78 FR 48424 - 36(b)(1) Arms Sales Notification

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    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B....

  17. 76 FR 32958 - 36(b)(1) Arms Sales Notification

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    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B....

  18. 78 FR 66340 - 36(b)(1) Arms Sales Notification

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    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

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    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  20. 75 FR 62792 - 36(b)(1) Arms Sales Notifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-13

    ... of the Secretary 36(b)(1) Arms Sales Notifications AGENCY: Defense Security Cooperation Agency, DoD... 36(b)(1) arms sales notifications to fulfill the requirements of section 155 of Public Law 104-164, dated 21 July 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English, DSCA/DBO/CFM, (703)...

  1. 78 FR 78941 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-27

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  2. 77 FR 46423 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-03

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B....

  3. 76 FR 79658 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-22

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  4. 76 FR 26707 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-09

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements...

  5. 76 FR 76954 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-09

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  6. 78 FR 42051 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-15

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  7. 76 FR 69707 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-09

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  8. 78 FR 26324 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-06

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B....

  9. 77 FR 35362 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-13

    ... Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  10. 78 FR 78939 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-27

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  11. 75 FR 114 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-04

    ...-68, 09-71 and 09-78] 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, Do... section 36(b)(1) arms sales notifications to fulfill the requirements of section 155 of Public Law 104-164 dated 21 July 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English, DSCA/DBO/CFM, (703)...

  12. 78 FR 49482 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-14

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  13. 76 FR 65701 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-24

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  14. 77 FR 49432 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-16

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  15. 76 FR 68432 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-04

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B....

  16. 77 FR 46415 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-03

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  17. 76 FR 66044 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-25

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  18. 76 FR 66046 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-25

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  19. 75 FR 20571 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-20

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, DoD...(b)(1) arms sales notifications to fulfill the requirements of section 155 of Public Law 104-164 dated 21 July 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English, DSCA/DBO/CFM, (703)...

  20. 78 FR 66338 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-05

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  1. 78 FR 26328 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-06

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B....

  2. 77 FR 53182 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-31

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B....

  3. 77 FR 49430 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-16

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B....

  4. 77 FR 49434 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-16

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  5. 76 FR 28956 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-19

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of...

  6. 77 FR 49436 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-16

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  7. 78 FR 46579 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-01

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21, 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English,...

  8. 17 CFR 260.10b-1 - Calculation of percentages.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Calculation of percentages. 260.10b-1 Section 260.10b-1 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION... Calculation of percentages. The percentages of voting securities and other securities specified in section...

  9. 26 CFR 1.269B-1 - Stapled foreign corporations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 3 2010-04-01 2010-04-01 false Stapled foreign corporations. 1.269B-1 Section 1... (CONTINUED) INCOME TAXES Items Not Deductible § 1.269B-1 Stapled foreign corporations. (a) Treatment as a domestic corporation—(1) General rule. Except as otherwise provided, if a foreign corporation is a...

  10. 26 CFR 301.269B-1 - Stapled foreign corporations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Stapled foreign corporations. 301.269B-1....269B-1 Stapled foreign corporations. In accordance with section 269B(a)(1), a stapled foreign corporation is subject to the same taxes that apply to a domestic corporation under Title 26 of the...

  11. 26 CFR 1.677(b)-1 - Trusts for support.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Trusts for support. 1.677(b)-1 Section 1.677(b... (CONTINUED) INCOME TAXES Grantors and Others Treated As Substantial Owners § 1.677(b)-1 Trusts for support. (a) Section 677(b) provides that a grantor is not treated as the owner of a trust merely because...

  12. 76 FR 60467 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-29

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of...: a Foreign Military Sales Order II (FMSO II) to provide funds for blanket order requisitions,...

  13. 76 FR 56181 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-12

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section.... (vi) Sales Commission, Fee, etc., Paid, Offered, or Agreed to be Paid: None. (vii) Sensitivity...

  14. Mycobacterium tuberculosis WhiB1 is an essential DNA-binding protein with a nitric oxide-sensitive iron-sulfur cluster.

    PubMed

    Smith, Laura J; Stapleton, Melanie R; Fullstone, Gavin J M; Crack, Jason C; Thomson, Andrew J; Le Brun, Nick E; Hunt, Debbie M; Harvey, Evelyn; Adinolfi, Salvatore; Buxton, Roger S; Green, Jeffrey

    2010-12-15

    Mycobacterium tuberculosis is a major pathogen that has the ability to establish, and emerge from, a persistent state. Wbl family proteins are associated with developmental processes in actinomycetes, and M. tuberculosis has seven such proteins. In the present study it is shown that the M. tuberculosis H37Rv whiB1 gene is essential. The WhiB1 protein possesses a [4Fe-4S]2+ cluster that is stable in air but reacts rapidly with eight equivalents of nitric oxide to yield two dinuclear dinitrosyl-iron thiol complexes. The [4Fe-4S] form of WhiB1 did not bind whiB1 promoter DNA, but the reduced and oxidized apo-WhiB1, and nitric oxide-treated holo-WhiB1 did bind to DNA. Mycobacterium smegmatis RNA polymerase induced transcription of whiB1 in vitro; however, in the presence of apo-WhiB1, transcription was severely inhibited, irrespective of the presence or absence of the CRP (cAMP receptor protein) Rv3676, which is known to activate whiB1 expression. Footprinting suggested that autorepression of whiB1 is achieved by apo-WhiB1 binding at a region that overlaps the core promoter elements. A model incorporating regulation of whiB1 expression in response to nitric oxide and cAMP is discussed with implications for sensing two important signals in establishing M. tuberculosis infections.

  15. CYP1B1 and hormone-induced cancer.

    PubMed

    Gajjar, Ketan; Martin-Hirsch, Pierre L; Martin, Francis L

    2012-11-01

    Cancers in hormone-responsive tissues (e.g., breast, ovary, endometrium, prostate) occur at high incidence rates worldwide. However, their genetic basis remains poorly understood. Studies to date suggest that endogenous/exogenous oestrogen and environmental carcinogens may play a role in development and/or progression of hormone-induced cancers via oxidative oestrogen metabolism. Cytochrome P450 1B1 is a key enzyme in its oestrogen metabolism pathway, giving rise to hydroxylation and conjugation. Although CYP1B1 is expressed in many cancers, particularly high levels of expression are observed in oestrogen-mediated disease. CYP1B1 is more readily found in tumour tissue compared to normal. Given the role of CYP1B1 in pro-carcinogen and oestrogen metabolism, polymorphisms in CYP1B1 could result in modifications in its enzyme activity and subsequently lead to hormone-mediated carcinogenesis. CYP1B1 may also be involved in progression of the disease by altering the tissue response to hormones and clinical response to chemotherapy. The exact mechanism behind these events is complex and unclear. Only a few functional single nucleotide polymorphisms of CYP1B1 are known to result in amino acid substitutions and have been extensively investigated. Studies examining the contribution of different CYP1B1 alleles to hormone-mediated cancer risks are inconsistent. The main focus of this review is to appraise the available studies linking the pathogenesis of the hormone-induced cancers to various CYP1B1 polymorphisms. Additionally, we explore the role of a neuronal protein, γ-synuclein, in CYP1B1-mediated pathogenesis.

  16. The Role of B-1 Cells in Inflammation

    PubMed Central

    Aziz, Monowar; Holodick, Nichol E.; Rothstein, Thomas L.; Wang, Ping

    2015-01-01

    B-1 lymphocytes exhibit unique phenotypic, ontogenic, and functional characteristics that differ from the conventional B-2 cells. B-1 cells spontaneously secrete germline-like, repertoire skewed polyreactive natural antibody, which acts as a first line of defense by neutralizing a wide range of pathogens before launching of the adaptive immune response. Immunomodulatory molecules, such as interleukin-10 (IL-10), adenosine, granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-3, and IL-35 are also produced by B-1 cells in the presence or absence of stimulation, which regulate acute and chronic inflammatory diseases. Considerable progress has been made during the past three decades since the discovery of B-1 cells, which has not only improved our understanding of their phenotypic and ontogenic uniqueness but also their role in various inflammatory diseases including influenza, pneumonia, sepsis, atherosclerosis, inflammatory bowel disease (IBD), autoimmunity, obesity and diabetes mellitus. Recent identification of human B-1 cells widens the scope of this field, leading to novel innovations that can be implemented from bench to bedside. Among the vast number of studies on B-1 cells, we have carried out a literature review highlighting current trends in the study of B-1 cell involvement during inflammation, which may result in a paradigm shift towards sustainable therapeutics in various inflammatory diseases. PMID:26427372

  17. CYP1B1: a unique gene with unique characteristics.

    PubMed

    Faiq, Muneeb A; Dada, Rima; Sharma, Reetika; Saluja, Daman; Dada, Tanuj

    2014-01-01

    CYP1B1, a recently described dioxin inducible oxidoreductase, is a member of the cytochrome P450 superfamily involved in the metabolism of estradiol, retinol, benzo[a]pyrene, tamoxifen, melatonin, sterols etc. It plays important roles in numerous physiological processes and is expressed at mRNA level in many tissues and anatomical compartments. CYP1B1 has been implicated in scores of disorders. Analyses of the recent studies suggest that CYP1B1 can serve as a universal/ideal cancer marker and a candidate gene for predictive diagnosis. There is plethora of literature available about certain aspects of CYP1B1 that have not been interpreted, discussed and philosophized upon. The present analysis examines CYP1B1 as a peculiar gene with certain distinctive characteristics like the uniqueness in its chromosomal location, gene structure and organization, involvement in developmentally important disorders, tissue specific, not only expression, but splicing, potential as a universal cancer marker due to its involvement in key aspects of cellular metabolism, use in diagnosis and predictive diagnosis of various diseases and the importance and function of CYP1B1 mRNA in addition to the regular translation. Also CYP1B1 is very difficult to express in heterologous expression systems, thereby, halting its functional studies. Here we review and analyze these exceptional and startling characteristics of CYP1B1 with inputs from our own experiences in order to get a better insight into its molecular biology in health and disease. This may help to further understand the etiopathomechanistic aspects of CYP1B1 mediated diseases paving way for better research strategies and improved clinical management.

  18. 6β-hydroxytestosterone, a cytochrome P450 1B1 metabolite of testosterone, contributes to angiotensin II-induced hypertension and its pathogenesis in male mice.

    PubMed

    Pingili, Ajeeth K; Kara, Mehmet; Khan, Nayaab S; Estes, Anne M; Lin, Zongtao; Li, Wei; Gonzalez, Frank J; Malik, Kafait U

    2015-06-01

    Previously, we showed that Cyp1b1 gene disruption minimizes angiotensin II-induced hypertension and associated pathophysiological changes in male mice. This study was conducted to test the hypothesis that cytochrome P450 1B1-generated metabolites of testosterone, 6β-hydroxytestosterone and 16α-hydroxytestosterone, contribute to angiotensin II-induced hypertension and its pathogenesis. Angiotensin II infusion for 2 weeks increased cardiac cytochrome P450 1B1 activity and plasma levels of 6β-hydroxytestosterone, but not 16α-hydroxytestosterone, in Cyp1b1(+/+) mice without altering Cyp1b1 gene expression; these effects of angiotensin II were not observed in Cyp1b1(-/-) mice. Angiotensin II-induced increase in systolic blood pressure and associated cardiac hypertrophy, and fibrosis, measured by intracardiac accumulation of α-smooth muscle actin, collagen, and transforming growth factor-β, and increased nicotinamide adenine dinucleotide phosphate oxidase activity and production of reactive oxygen species; these changes were minimized in Cyp1b1(-/-) or castrated Cyp1b1(+/+) mice, and restored by treatment with 6β-hydroxytestoterone. In Cyp1b1(+/+) mice, 6β-hydroxytestosterone did not alter the angiotensin II-induced increase in systolic blood pressure; the basal systolic blood pressure was also not affected by this agent in either genotype. Angiotensin II or castration did not alter cardiac, angiotensin II type 1 receptor, angiotensin-converting enzyme, Mas receptor, or androgen receptor mRNA levels in Cyp1b1(+/+) or in Cyp1b1(-/-) mice. These data suggest that the testosterone metabolite, 6β-hydroxytestosterone, contributes to angiotensin II-induced hypertension and associated cardiac pathogenesis in male mice, most probably by acting as a permissive factor. Moreover, cytochrome P450 1B1 could serve as a novel target for developing agents for treating renin-angiotensin and testosterone-dependent hypertension and associated pathogenesis in males.

  19. 76 FR 46754 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-03

    ...The Department of Defense is publishing the unclassified text of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21,...

  20. 78 FR 36538 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-18

    ...The Department of Defense is publishing the unclassified text of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21,...

  1. 77 FR 77043 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-31

    ...The Department of Defense is publishing the unclassified text of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21,...

  2. 78 FR 41039 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-09

    ...The Department of Defense is publishing the unclassified text of a section 36(b)(1) arms sales notification. This is published to fulfill the requirements of section 155 of Public Law 104-164 dated July 21,...

  3. Properties of L=1 B(1) and B(2)* mesons.

    PubMed

    Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Aguilo, E; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Ancu, L S; Andeen, T; Anderson, S; Andrieu, B; Anzelc, M S; Arnoud, Y; Arov, M; Arthaud, M; Askew, A; Asman, B; Assis Jesus, A C S; Atramentov, O; Autermann, C; Avila, C; Ay, C; Badaud, F; Baden, A; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, S; Banerjee, P; Barberis, E; Barfuss, A-F; Bargassa, P; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Bellavance, A; Benitez, J A; Beri, S B; Bernardi, G; Bernhard, R; Berntzon, L; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Biscarat, C; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Borissov, G; Bos, K; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Buchanan, N J; Buchholz, D; Buehler, M; Buescher, V; Burdin, S; Burke, S; Burnett, T H; Buszello, C P; Butler, J M; Calfayan, P; Calvet, S; Cammin, J; Caron, S; Carvalho, W; Casey, B C K; Cason, N M; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chan, K; Chandra, A; Charles, F; Cheu, E; Chevallier, F; Cho, D K; Choi, S; Choudhary, B; Christofek, L; Christoudias, T; Cihangir, S; Claes, D; Clément, C; Clément, B; Coadou, Y; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M-C; Crépé-Renaudin, S; Cutts, D; Cwiok, M; da Motta, H; Das, A; Davies, G; De, K; de Jong, S J; de Jong, P; De La Cruz-Burelo, E; Martins, C De Oliveira; Degenhardt, J D; Déliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Dominguez, A; Dong, H; Dudko, L V; Duflot, L; Dugad, S R; Duggan, D; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Ermolov, P; Evans, H; Evdokimov, A; Evdokimov, V N; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Ford, M; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Galyaev, E; Garcia, C; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Gelé, D; Gerber, C E; Gershtein, Y; Gillberg, D; Ginther, G; Gollub, N; Gómez, B; Goussiou, A; Grannis, P D; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, J; Guo, F; Gutierrez, P; Gutierrez, G; Haas, A; Hadley, N J; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Hanagaki, K; Hansson, P; Harder, K; Harel, A; Harrington, R; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hoeth, H; Hohlfeld, M; Hong, S J; Hooper, R; Hossain, S; Houben, P; Hu, Y; Hubacek, Z; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jarvis, C; Jesik, R; Johns, K; Johnson, C; Johnson, M; Jonckheere, A; Jonsson, P; Juste, A; Käfer, D; Kahn, S; Kajfasz, E; Kalinin, A M; Kalk, J R; Kalk, J M; Kappler, S; Karmanov, D; Kasper, J; Kasper, P; Katsanos, I; Kau, D; Kaur, R; Kaushik, V; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y M; Khatidze, D; Kim, H; Kim, T J; Kirby, M H; Kirsch, M; Klima, B; Kohli, J M; Konrath, J-P; Kopal, M; Korablev, V M; Kothari, B; Kozelov, A V; Krop, D; Kryemadhi, A; Kuhl, T; Kumar, A; Kunori, S; Kupco, A; Kurca, T; Kvita, J; Lacroix, F; Lam, D; Lammers, S; Landsberg, G; Lazoflores, J; Lebrun, P; Lee, W M; Leflat, A; Lehner, F; Lellouch, J; Lesne, V; Leveque, J; Lewis, P; Li, J; Li, Q Z; Li, L; Lietti, S M; Lima, J G R; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobo, L; Lobodenko, A; Lokajicek, M; Lounis, A; Love, P; Lubatti, H J; Lyon, A L; Maciel, A K A; Mackin, D; Madaras, R J; Mättig, P; Magass, C; Magerkurth, A; Makovec, N; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martin, B; McCarthy, R; Melnitchouk, A; Mendes, A; Mendoza, L; Mercadante, P G; Merkin, M; Merritt, K W; Meyer, J; Meyer, A; Michaut, M; Millet, T; Mitrevski, J; Molina, J; Mommsen, R K; Mondal, N K; Moore, R W; Moulik, T; Muanza, G S; Mulders, M; Mulhearn, M; Mundal, O; Mundim, L; Nagy, E; Naimuddin, M; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Neustroev, P; Nilsen, H; Nomerotski, A; Novaes, S F; Nunnemann, T; O'Dell, V; O'Neil, D C; Obrant, G; Ochando, C; Onoprienko, D; Oshima, N; Osta, J; Otec, R; Y Garzón, G J Otero; Owen, M; Padley, P; Pangilinan, M; Parashar, N; Park, S-J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Penning, B; Perea, P M; Peters, K; Peters, Y; Pétroff, P; Petteni, M; Piegaia, R; Piper, J; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M-E; Polozov, P; Pompos, A; Pope, B G; Popov, A V; Potter, C; da Silva, W L Prado; Prosper, H B; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rakitine, A; Rangel, M S; Rani, K J; Ranjan, K; Ratoff, P N; Renkel, P; Reucroft, S; Rich, P; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Robinson, S; Rodrigues, R F; Royon, C; Rubinov, P; Ruchti, R; Safronov, G; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Santoro, A; Savage, G; Sawyer, L; Scanlon, T; Schaile, D; Schamberger, R D; Scheglov, Y; Schellman, H; Schieferdecker, P; Schliephake, T; Schmitt, C; Schwanenberger, C; Schwartzman, A; Schwienhorst, R; Sekaric, J; Sengupta, S; Severini, H; Shabalina, E; Shamim, M; Shary, V; Shchukin, A A; Shivpuri, R K; Shpakov, D; Siccardi, V; Simak, V; Sirotenko, V; Skubic, P; Slattery, P; Smirnov, D; Smith, R P; Snow, J; Snow, G R; Snyder, S; Söldner-Rembold, S; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Souza, M; Spurlock, B; Stark, J; Steele, J; Stolin, V; Stone, A; Stoyanova, D A; Strandberg, J; Strandberg, S; Strang, M A; Strauss, M; Strauss, E; Ströhmer, R; Strom, D; Strovink, M; Stutte, L; Sumowidagdo, S; Svoisky, P; Sznajder, A; Talby, M; Tamburello, P; Tanasijczuk, A; Taylor, W; Telford, P; Temple, J; Tiller, B; Tissandier, F; Titov, M; Tokmenin, V V; Tomoto, M; Toole, T; Torchiani, I; Trefzger, T; Tsybychev, D; Tuchming, B; Tully, C; Tuts, P M; Unalan, R; Uvarov, S; Uvarov, L; Uzunyan, S; Vachon, B; van den Berg, P J; van Eijk, B; Van Kooten, R; van Leeuwen, W M; Varelas, N; Varnes, E W; Vartapetian, A; Vasilyev, I A; Vaupel, M; Verdier, P; Vertogradov, L S; Verzocchi, M; Villeneuve-Seguier, F; Vint, P; Vokac, P; Von Toerne, E; Voutilainen, M; Vreeswijk, M; Wagner, R; Wahl, H D; Wang, L; Wang, M H L S; Warchol, J; Watts, G; Wayne, M; Weber, M; Weber, G; Weerts, H; Wenger, A; Wermes, N; Wetstein, M; White, A; Wicke, D; Wilson, G W; Williams, M R J; Wimpenny, S J; Wobisch, M; Wood, D R; Wyatt, T R; Xie, Y; Yacoob, S; Yamada, R; Yan, M; Yasuda, T; Yatsunenko, Y A; Yip, K; Yoo, H D; Youn, S W; Yu, J; Yu, C; Yurkewicz, A; Zatserklyaniy, A; Zeitnitz, C; Zhang, D; Zhao, T; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zieminski, A; Zivkovic, L; Zutshi, V; Zverev, E G

    2007-10-26

    This Letter presents the first strong evidence for the resolution of the excited B mesons B(1) and B(2)* as two separate states in fully reconstructed decays to B(+)(*)pi(-). The mass of B(1) is measured to be 5720.6+/-2.4+/-1.4 MeV/c(2) and the mass difference DeltaM between B(2)* and B(1) is 26.2+/-3.1+/-0.9 MeV/c;{2}, giving the mass of the B(2)* as 5746.8+/-2.4+/-1.7 MeV/c(2). The production rate for B(1) and B(2)* mesons is determined to be a fraction (13.9+/-1.9+/-3.2)% of the production rate of the B+ meson.

  4. Supercritical Fluid Extraction of Aflatoxin B 1 from Soil

    EPA Science Inventory

    This research describes the development of a Supercritical Fluid Extraction (SFE) method to recover aflatoxin B1 from fortified soil. The effects of temperature, pressure, modifier (identity and percentage), and extraction type were assessed. Using the optimized SFE conditions, ...

  5. Hepato- and nephroprotective effects of bradykinin potentiating factor from scorpion (Buthus occitanus) venom on mercuric chloride-treated rats

    PubMed Central

    Salman, Muhammad M. A.; Kotb, Ahmed M.; Haridy, Mohie A. M.; Hammad, Seddik

    2016-01-01

    Bioactive peptides such as bradykinin potentiating factor (BPF), have, anti-oxidative, anti-inflammatory, immunomodulatory and ameliorative effects in chronic diseases and play a potential role in cancer prevention. It is known that the liver and kidney accumulate inorganic mercury upon exposure, which often leads to mercury intoxication in these organs. In this study, we investigated the effect of bradykinin potentiating factor (BPF), a scorpion venom peptide, on mercuric chloride-induced hepatic and renal toxicity in rats. We used 20 adult male Albino rats divided into four equal groups: the first group was injected with saline (control); the second group was administered daily with mercuric chloride (HgCl2) for 2 weeks; the third group was administered with BPF twice weekly for 2 successive weeks, while the fourth group was exposed to BPF followed by HgCl2. We observed that HgCl2 treated rats had a significant increase in serum ALT, AST, ALP, creatinine and urea levels compared to control. Furthermore, HgCl2 treated rats showed a marked decrease in total proteins, albumin and uric acids compared to control. The previously studied parameters were not significantly changed in BPF pretreated rats compared to control. Moreover, a significant decrease in the activities of glutathione perioxidase (GSH), superoxide dismutase (SOD), and catalase (CAT), in addition to a significant increase in the level of malondialdehyde (MDA) were observed in hepatic and renal tissues of rats after HgCl2 treatment. In contrast, the HgCl2/BPF treated rats showed a significant elevation in the activity of GSH, SOD, and CAT accompanied with a significant regression in the level of MDA compared to the HgCl2 exposed rats. We conclude that treatment with BPF is a promising prophylactic approach for the management of mercuric chloride-induced hepato- and nephro-toxicities. PMID:28337111

  6. Bowman-Birk protease inhibitor from Vigna unguiculata seeds enhances the action of bradykinin-related peptides.

    PubMed

    da Cunha Morales Álvares, Alice; Schwartz, Elisabeth Ferroni; Amaral, Nathalia Oda; Trindade, Neidiane Rosa; Pedrino, Gustavo Rodrigues; Silva, Luciano Paulino; de Freitas, Sonia Maria

    2014-10-30

    The hydrolysis of bradykinin (Bk) by different classes of proteases in plasma and tissues leads to a decrease in its half-life. Here, Bk actions on smooth muscle and in vivo cardiovascular assays in association with a protease inhibitor, Black eyed-pea trypsin and chymotrypsin inhibitor (BTCI) and also under the effect of trypsin and chymotrypsin were evaluated. Two synthetic Bk-related peptides, Bk1 and Bk2, were used to investigate the importance of additional C-terminal amino acid residues on serine protease activity. BTCI forms complexes with Bk and analogues at pH 5.0, 7.4 and 9.0, presenting binding constants ranging from 103 to 104 M-1. Formation of BTCI-Bk complexes is probably driven by hydrophobic forces, coupled with slight conformational changes in BTCI. In vitro assays using guinea pig (Cavia porcellus) ileum showed that Bk retains the ability to induce smooth muscle contraction in the presence of BTCI. Moreover, no alteration in the inhibitory activity of BTCI in complex with Bk and analogous was observed. When the BTCI and BTCI-Bk complexes were tested in vivo, a decrease of vascular resistance and consequent hypotension and potentiating renal and aortic vasodilatation induced by Bk and Bk2 infusions was observed. These results indicate that BTCI-Bk complexes may be a reliable strategy to act as a carrier and protective approach for Bk-related peptides against plasma serine proteases cleavage, leading to an increase in their half-life. These findings also indicate that BTCI could remain stable in some tissues to inhibit chymotrypsin or trypsin-like enzymes that cleave and inactivate bradykinin in situ.

  7. Bradykinin and vasopressin stimulate Na/sup +/-K/sup +/-Cl/sup -/ cotransport in cultured endothelial cells

    SciTech Connect

    Brock, T.A.; Brugnara, C.; Canessa, M.; Gimbrone, M.A. Jr.

    1986-06-01

    The authors have characterized a Na/sup +/-K/sup +/-Cl/sup -/ cotransporter in vascular endothelial cells (EC) cultured from different blood vessels and species that is inhibited by the diuretics furosemide and bumentanide. Inward /sup 86/Rb influx transported by the Na/sup +/-K/sup +/ pump in cultured EC from bovine and pig aorta, bovine vena cava, and baboon cephalic vein but not in human umbilical or saphenous vein EC. External Na/sup +/ or Cl/sup -/-stimulated, ouabain-insensitive /sup 86/Rb influx is equal to furosemide or bumetanide-sensitive /sup 86/Rb influx. Ouabain-insensitive /sup 22/Na influx is also partially inhibited by these drugs and stimulated by increasing external K/sup +/ or Cl/sup -/. Net Na/sup +/ extrusion occurs via the Na/sup +/-K/sup +/-Cl/sup -/ cotransporter in the absence of external K/sup +/, whereas net Na/sup +/ influx occurs at higher external K/sup +/. Maximal concentrations (100 nM) of bradykinin and vasopressin increase the initial rate of bumetanide-sensitive /sup 86/Rb influx by approx.60 and 70%. Addition of either ethyleneglycol-bis(..beta..-aminotethylether)-N,N'-tetraacetic acid or LaCl/sub 3/ (to block calcium influx) prevents bradykinin-stimulated /sup 86/Rb influx. When intracellular calcium is elevated using ionomycin (100 nM), a Ca/sup 2 +/ionophore, bumetanide-sensitive /sup 86/Rb influx increases approx.twofold. In contrast, isoproterenol (100 ..mu..M) and forskolin (50 /sup +/M), adenylate cyclase stimulators, decrease furosemide-sensitive /sup 86/Rb influx. Thus in certain types of cultured EC, a Na/sup +/-K/sup +/-Cl/sup -/ cotransporter mediates a fraction of K/sup +/ influx quantitatively as important as the Na/sup +/-K/sup +/ pump (ouabain-sensitive /sup 86/Rb influx) and appears to be modulated by Ca/sup 2 +/ and cyclic nucleotides.

  8. Resetting of renal tissular renin-angiotensin and bradykinin-kallikrein systems after unilateral kidney denervation in rats.

    PubMed

    Bohlender, Jürgen M; Nussberger, Jürg; Birkhäuser, Frédéric; Grouzmann, Eric; Thalmann, George N; Imboden, Hans

    2017-02-20

    The renal tissular renin-angiotensin and bradykinin-kallikrein systems control kidney function together with the renal sympathetic innervation but their interaction is still unclear. To further elucidate this relationship, we investigated these systems in rats 6 days after left kidney denervation (DNX, n = 8) compared to sham-operated controls (CTR, n = 8). Plasma renin concentration was unchanged in DNX vs. CTR (p = NS). Kidney bradykinin (BK) and angiotensin (Ang) I and II concentrations decreased bilaterally in DNX vs. CTR rats (~20 to 40%, p < 0.05) together with Ang IV and V concentrations that were extremely low (p = NS). Renin, Ang III and dopamine concentrations decreased by ~25 to 50% and norepinephrine concentrations by 99% in DNX kidneys (p < 0.05) but were unaltered in opposite kidneys. Ang II/I and KA were comparable in DNX, contralateral and CTR kidneys. Ang III/II increased in right vs. DNX or CTR kidneys (40-50%, p < 0.05). Ang II was mainly located in tubular epithelium by immunocytological staining and its cellular distribution was unaffected by DNX. Moreover, the angiotensinergic and catecholaminergic innervation of right kidneys was unchanged vs. CTR. We found an important dependency of tissular Ang and BK levels on the renal innervation that may contribute to the resetting of kidney function after DNX. The DNX-induced peptide changes were not readily explained by kidney KA, renin or plasma Ang I generation. However, tissular peptide metabolism and compartmentalization may have played a central role. The mechanisms behind the concentration changes remain unclear and deserve further clarification.

  9. Hematopoietic stem cell-independent B-1a lineage.

    PubMed

    Ghosn, Eliver Eid Bou; Yang, Yang

    2015-12-01

    The accepted dogma has been that a single long-term hematopoietic stem cell (LT-HSC) can reconstitute all components of the immune system. However, our single-cell transfer studies have shown that highly purified LT-HSCs selectively fail to reconstitute B-1a cells in otherwise fully reconstituted hosts (i.e., LT-HSCs fully reconstitute follicular, marginal zone, and B-1b B cells, but not B-1a cells). These results suggest that B-1a cells are a separate B cell lineage that develops independently of classical LT-HSCs. We provide an evolutionary two-pathway development model (HSC independent versus HSC dependent), and suggest that this lineage separation is employed not only by B cells but by all hematopoietic lineages. Collectively, these findings challenge the current notion that LT-HSCs can reconstitute all components of the immune system and raise key questions about human HSC transplantation. We discuss the implications of these findings in light of our recent studies demonstrating the ability of B-1a cells to elicit antigen-specific responses that differ markedly from those mounted by follicular B cells. These findings have implications for vaccine development, in particular vaccines that may elicit the B-1a repertoire.

  10. CYP1B1-mediated Pathobiology of Primary Congenital Glaucoma.

    PubMed

    Faiq, Muneeb A; Dada, Rima; Qadri, Rizwana; Dada, Tanuj

    2015-01-01

    CYP1B1 is a dioxin-inducible enzyme belonging to the cytochrome P450 superfamily. It has been observed to be important in a variety of developmental processes including in utero development of ocular structures. Owing to its role in the developmental biology of eye, its dysfunction can lead to ocular developmental defects. This has been found to be true and CYP1B1 mutations have been observed in a majority of primary congenital glaucoma (PCG) patients from all over the globe. Primary congenital glaucoma is an irreversibly blinding childhood disorder (onset at birth or early infancy) typified by anomalous development of trabecular meshwork (TM). How CYP1B1 causes PCG is not known; however, some basic investigations have been reported. Understanding the CYP1B1 mediated etiopathomechanism of PCG is very important to identify targets for therapy and preventive management. In this perspective, we will make an effort to reconstruct the pathomechanism of PCG in the light of already reported information about the disease and the CYP1B1 gene. How to cite this article: Faiq MA, Dada R, Qadri R, Dada T. CYP1 B1-mediated Pathobiology of Primary Congenital Glaucoma. J Curr Glaucoma Pract 2015;9(3):77-80.

  11. CYP1B1-mediated Pathobiology of Primary Congenital Glaucoma

    PubMed Central

    Faiq, Muneeb A; Dada, Rima; Qadri, Rizwana

    2015-01-01

    ABSTRACT CYP1B1 is a dioxin-inducible enzyme belonging to the cytochrome P450 superfamily. It has been observed to be important in a variety of developmental processes including in utero development of ocular structures. Owing to its role in the developmental biology of eye, its dysfunction can lead to ocular developmental defects. This has been found to be true and CYP1B1 mutations have been observed in a majority of primary congenital glaucoma (PCG) patients from all over the globe. Primary congenital glaucoma is an irreversibly blinding childhood disorder (onset at birth or early infancy) typified by anomalous development of trabecular meshwork (TM). How CYP1B1 causes PCG is not known; however, some basic investigations have been reported. Understanding the CYP1B1 mediated etiopathomechanism of PCG is very important to identify targets for therapy and preventive management. In this perspective, we will make an effort to reconstruct the pathomechanism of PCG in the light of already reported information about the disease and the CYP1B1 gene. How to cite this article: Faiq MA, Dada R, Qadri R, Dada T. CYP1 B1-mediated Pathobiology of Primary Congenital Glaucoma. J Curr Glaucoma Pract 2015;9(3):77-80. PMID:26997841

  12. Phosphorylation of the adaptor protein SH2B1β regulates its ability to enhance growth hormone-dependent macrophage motility.

    PubMed

    Su, Hsiao-Wen; Lanning, Nathan J; Morris, David L; Argetsinger, Lawrence S; Lumeng, Carey N; Carter-Su, Christin

    2013-04-15

    Previous studies have shown that growth hormone (GH) recruits the adapter protein SH2B1β to the GH-activated, GH receptor-associated tyrosine kinase JAK2, implicating SH2B1β in GH-dependent actin cytoskeleton remodeling, and suggesting that phosphorylation at serines 161 and 165 in SH2B1β releases SH2B1β from the plasma membrane. Here, we examined the role of SH2B1β in GH regulation of macrophage migration. We show that GH stimulates migration of cultured RAW264.7 macrophages, and primary cultures of peritoneal and bone marrow-derived macrophages. SH2B1β overexpression enhances, whereas SH2B1 knockdown inhibits, GH-dependent motility of RAW macrophages. At least two independent mechanisms regulate the SH2B1β-mediated changes in motility. In response to GH, tyrosines 439 and 494 in SH2B1β are phosphorylated. Mutating these tyrosines in SH2B1β decreases both basal and GH-stimulated macrophage migration. In addition, mutating the polybasic nuclear localization sequence (NLS) in SH2B1β or creating the phosphomimetics SH2B1β(S161E) or SH2B1β(S165E), all of which release SH2B1β from the plasma membrane, enhances macrophage motility. Conversely, SH2B1β(S161/165A) exhibits increased localization at the plasma membrane and decreased macrophage migration. Mutating the NLS or the nearby serine residues does not alter GH-dependent phosphorylation on tyrosines 439 and 494 in SH2B1β. Mutating tyrosines 439 and 494 does not affect localization of SH2B1β at the plasma membrane or movement of SH2B1β into focal adhesions. Taken together, these results suggest that SH2B1β enhances GH-stimulated macrophage motility via mechanisms involving phosphorylation of SH2B1β on tyrosines 439 and 494 and movement of SH2B1β out of the plasma membrane (e.g. as a result of phosphorylation of serines 161 and 165).

  13. Enhancement of arachidonic acid signaling pathway by nicotinic acid receptor HM74A.

    PubMed

    Tang, Yuting; Zhou, Lubing; Gunnet, Joseph W; Wines, Pamela G; Cryan, Ellen V; Demarest, Keith T

    2006-06-23

    HM74A is a G protein-coupled receptor for nicotinic acid (niacin), which has been used clinically to treat dyslipidemia for decades. The molecular mechanisms whereby niacin exerts its pleiotropic effects on lipid metabolism remain largely unknown. In addition, the most common side effect in niacin therapy is skin flushing that is caused by prostaglandin release, suggesting that the phospholipase A(2) (PLA(2))/arachidonic acid (AA) pathway is involved. Various eicosanoids have been shown to activate peroxisome-proliferator activated receptors (PPAR) that play a diverse array of roles in lipid metabolism. To further elucidate the potential roles of HM74A in mediating the therapeutic effects and/or side effects of niacin, we sought to explore the signaling events upon HM74A activation. Here we demonstrated that HM74A synergistically enhanced UTP- and bradykinin-mediated AA release in a pertussis toxin-sensitive manner in A431 cells. Activation of HM74A also led to Ca(2+)-mobilization and enhanced bradykinin-promoted Ca(2+)-mobilization through Gi protein. While HM74A increased ERK1/2 activation by the bradykinin receptor, it had no effects on UTP-promoted ERK1/2 activation.Furthermore, UTP- and bradykinin-mediated AA release was significantly decreased in the presence of both MAPK kinase inhibitor PD 098059 and PKC inhibitor GF 109203X. However, the synergistic effects of HM74A were not dramatically affected by co-treatment with both inhibitors, indicating the cross-talk occurred at the receptor level. Finally, stimulation of A431 cells transiently transfected with PPRE-luciferase with AA significantly induced luciferase activity, mimicking the effects of PPARgamma agonist rosiglitazone, suggesting that alteration of AA signaling pathway can regulate gene expression via endogenous PPARs.

  14. Enhancement of arachidonic acid signaling pathway by nicotinic acid receptor HM74A

    SciTech Connect

    Tang, Yuting . E-mail: ytang@prdus.jnj.com; Zhou, Lubing; Gunnet, Joseph W.; Wines, Pamela G.; Cryan, Ellen V.; Demarest, Keith T.

    2006-06-23

    HM74A is a G protein-coupled receptor for nicotinic acid (niacin), which has been used clinically to treat dyslipidemia for decades. The molecular mechanisms whereby niacin exerts its pleiotropic effects on lipid metabolism remain largely unknown. In addition, the most common side effect in niacin therapy is skin flushing that is caused by prostaglandin release, suggesting that the phospholipase A{sub 2} (PLA{sub 2})/arachidonic acid (AA) pathway is involved. Various eicosanoids have been shown to activate peroxisome-proliferator activated receptors (PPAR) that play a diverse array of roles in lipid metabolism. To further elucidate the potential roles of HM74A in mediating the therapeutic effects and/or side effects of niacin, we sought to explore the signaling events upon HM74A activation. Here we demonstrated that HM74A synergistically enhanced UTP- and bradykinin-mediated AA release in a pertussis toxin-sensitive manner in A431 cells. Activation of HM74A also led to Ca{sup 2+}-mobilization and enhanced bradykinin-promoted Ca{sup 2+}-mobilization through Gi protein. While HM74A increased ERK1/2 activation by the bradykinin receptor, it had no effects on UTP-promoted ERK1/2 activation.Furthermore, UTP- and bradykinin-mediated AA release was significantly decreased in the presence of both MAPK kinase inhibitor PD 098059 and PKC inhibitor GF 109203X. However, the synergistic effects of HM74A were not dramatically affected by co-treatment with both inhibitors, indicating the cross-talk occurred at the receptor level. Finally, stimulation of A431 cells transiently transfected with PPRE-luciferase with AA significantly induced luciferase activity, mimicking the effects of PPAR{gamma} agonist rosiglitazone, suggesting that alteration of AA signaling pathway can regulate gene expression via endogenous PPARs.

  15. Novel Roles for Kv7 Channels in Shaping Histamine-Induced Contractions and Bradykinin-Dependent Relaxations in Pig Coronary Arteries.

    PubMed

    Chen, Xingjuan; Li, Wennan; Hiett, S Christopher; Obukhov, Alexander G

    2016-01-01

    Voltage-gated Kv7 channels are inhibited by agonists of Gq-protein-coupled receptors, such as histamine. Recent works have provided evidence that inhibition of vascular Kv7 channels may trigger vessel contractions. In this study, we investigated how Kv7 activity modulates the histamine-induced contractions in "healthy" and metabolic syndrome (MetS) pig right coronary arteries (CAs). We performed isometric tension and immunohistochemical studies with domestic, lean Ossabaw, and MetS Ossabaw pig CAs. We found that neither the Kv7.2/Kv7.4/Kv7.5 activator ML213 nor the general Kv7 inhibitor XE991 altered the tension of CA rings under preload, indicating that vascular Kv7 channels are likely inactive in the preloaded rings. Conversely, ML213 potently dilated histamine-pre-contracted CAs, suggesting that Kv7 channels are activated during histamine applications and yet partially inhibited by histamine. Immunohistochemistry analysis revealed strong Kv7.4 immunostaining in the medial and intimal layers of the CA wall, whereas Kv7.5 immunostaining intensity was strong in the intimal but weak in the medial layers. The medial Kv7 immunostaining was significantly weaker in MetS Ossabaw CAs as compared to lean Ossabaw or domestic CAs. Consistently, histamine-pre-contracted MetS Ossabaw CAs exhibited attenuated ML213-dependent dilations. In domestic pig CAs, where medial Kv7 immunostaining intensity was stronger, histamine-induced contractions spontaneously decayed to ~31% of the peak amplitude within 4 minutes. Oppositely, in Ossabaw CAs, where Kv7 immunostaining intensity was weaker, the histamine-induced contractions were more sustained. XE991 pretreatment significantly slowed the decay rate of histamine-induced contractions in domestic CAs, supporting the hypothesis that increased Kv7 activity correlates with a faster rate of histamine-induced contraction decay. Alternatively, XE991 significantly decreased the amplitude of bradykinin-dependent dilations in pre-contracted CAs

  16. Novel Roles for Kv7 Channels in Shaping Histamine-Induced Contractions and Bradykinin-Dependent Relaxations in Pig Coronary Arteries

    PubMed Central

    Chen, Xingjuan; Li, Wennan; Hiett, S. Christopher; Obukhov, Alexander G.

    2016-01-01

    Voltage-gated Kv7 channels are inhibited by agonists of Gq-protein-coupled receptors, such as histamine. Recent works have provided evidence that inhibition of vascular Kv7 channels may trigger vessel contractions. In this study, we investigated how Kv7 activity modulates the histamine-induced contractions in “healthy” and metabolic syndrome (MetS) pig right coronary arteries (CAs). We performed isometric tension and immunohistochemical studies with domestic, lean Ossabaw, and MetS Ossabaw pig CAs. We found that neither the Kv7.2/Kv7.4/Kv7.5 activator ML213 nor the general Kv7 inhibitor XE991 altered the tension of CA rings under preload, indicating that vascular Kv7 channels are likely inactive in the preloaded rings. Conversely, ML213 potently dilated histamine-pre-contracted CAs, suggesting that Kv7 channels are activated during histamine applications and yet partially inhibited by histamine. Immunohistochemistry analysis revealed strong Kv7.4 immunostaining in the medial and intimal layers of the CA wall, whereas Kv7.5 immunostaining intensity was strong in the intimal but weak in the medial layers. The medial Kv7 immunostaining was significantly weaker in MetS Ossabaw CAs as compared to lean Ossabaw or domestic CAs. Consistently, histamine-pre-contracted MetS Ossabaw CAs exhibited attenuated ML213-dependent dilations. In domestic pig CAs, where medial Kv7 immunostaining intensity was stronger, histamine-induced contractions spontaneously decayed to ~31% of the peak amplitude within 4 minutes. Oppositely, in Ossabaw CAs, where Kv7 immunostaining intensity was weaker, the histamine-induced contractions were more sustained. XE991 pretreatment significantly slowed the decay rate of histamine-induced contractions in domestic CAs, supporting the hypothesis that increased Kv7 activity correlates with a faster rate of histamine-induced contraction decay. Alternatively, XE991 significantly decreased the amplitude of bradykinin-dependent dilations in pre

  17. Evidence for the eta_b(1S) in the Decay Upsilon(2S)-> gamma eta_b(1S)

    SciTech Connect

    Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Lopez, L.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Battaglia, M.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Karlsruhe U., EKP /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /INFN, Naples /Naples U. /INFN, Naples /INFN, Naples /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /Pennsylvania U. /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DSM, DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

    2009-12-14

    We have performed a search for the {eta}{sub b}(1S) meson in the radiative decay of the {Upsilon}(2S) resonance using a sample of 91.6 million {Upsilon}(2S) events recorded with the BABAR detector at the PEP-II B factory at the SLAC National Accelerator Laboratory. We observe a peak in the photon energy spectrum at E{sub {gamma}} = 610.5{sub -4.3}{sup +4.5}(stat) {+-} 1.8(syst) MeV, corresponding to an {eta}{sub b}(1S) mass of 9392.9{sub -4.8}{sup +4.6}(stat) {+-} 1.9(syst) MeV/c{sup 2}. The branching fraction for the decay {Upsilon}(2S) {yields} {gamma}{eta}{sub b}(1S) is determined to be (4.2{sub -1.0}{sup +1.1}(stat) {+-} 0.9(syst)) x 10{sup -4}. The ratio {Beta}({Upsilon}(2S) {yields} {gamma}{eta}{sub b}(1S))/{Beta}({Upsilon}(3S) {yields} {gamma}{eta}{sub b}(1S)) = 0.89{sub -0.23}{sup +0.25}(stat){sub -0.16}{sup +0.12}(syst) is consistent with the ratio expected for magnetic dipole transitions to the {eta}{sub b}(1S) meson.

  18. The 1990 vertical distribution of two important halons (F-12B1 and F-13B1) in the tropics

    NASA Technical Reports Server (NTRS)

    Singh, O. N.; Borchers, R.; Lal, Shyam; Subbarya, B. H.; Krueger, Bernd C.; Fabian, Peter

    1994-01-01

    The first vertical profiles of F-12B1 and F-13B1 had been obtained in the tropical troposphere and stratosphere by us in 1987. The measurement of these substances responsible for almost the entire anthropogenic contribution to the stratospheric BrO(x) budget is important in the tropics, as tropical upwelling provides their injection along with that of other pollutants, into the stratosphere. To ascertain the trends of these distributions and foster the data, the 1987 experiment was repeated in April 1990. Like 1987, the MPAE cryogenic whole air sampler was launched on a balloon from Hyderabad, India (17.5 deg N), and 14 samples were collected between 10 and 35 km altitude. The results obtained by means of GC and GC-MS analyses showed that the atmospheric abundance of both F-12B1 and F-13B1 is increasing at a fast rate, respectively by about 15 percent and 10 percent per year. From 1987 to 1990, F-12B1 and F-13B1 tropospheric mixing ratios have been growing from 1.2 and 1.3 ppt to 1.8 and 1.7 ppt, respectively. The vertical profiles will be discussed.

  19. B1 Mapping by Bloch-Siegert Shift

    PubMed Central

    Sacolick, Laura I.; Wiesinger, Florian; Hancu, Ileana; Vogel, Mika W.

    2010-01-01

    A novel method for B1+ field mapping based on the Bloch-Siegert shift is presented. Unlike conventionally applied double-angle or other signal magnitude-based methods it encodes the B1 information into signal phase, resulting in important advantages in terms of acquisition speed, accuracy and robustness. The Bloch Siegert frequency shift is caused by irradiating with an off-resonance RF pulse following conventional spin excitation. When applying the off-resonance RF in the kHz range, spin nutation can be neglected and the primarily observed effect is a spin precession frequency shift. This shift is proportional to the square of the RF field magnitude B12. Adding gradient image encoding following the off-resonance pulse allows one to acquire spatially resolved B1 maps. The frequency shift from the Bloch-Siegert effect gives a phase shift in the image that is proportional to B12. The phase difference of two acquisitions, with the RF pulse applied at two frequencies symmetrically around the water resonance is used to eliminate undesired off-resonance effects due to B0 inhomogeneity and chemical shift. In-vivo Bloch Siegert B1 mapping with 25 seconds / slice is demonstrated to be quantitatively comparable to a 21 minute double-angle map. As such this method enables robust, high resolution B1+ mapping in a clinically acceptable time frame. PMID:20432302

  20. Occurrence of aflatoxin B1 in natural products

    PubMed Central

    Prado, Guilherme; Altoé, Aline F.; Gomes, Tatiana C. B.; Leal, Alexandre S.; Morais, Vanessa A. D.; Oliveira, Marize S.; Ferreira, Marli B.; Gomes, Mateus B.; Paschoal, Fabiano N.; von S. Souza, Rafael; Silva, Daniela A.; Cruz Madeira, Jovita E. G.

    2012-01-01

    The media claims for the consumption of natural resource-based food have gradually increased in both developing and developed countries. The interest in the safety of these products is partially due to the possible presence of toxigenic fungi acting as mycotoxin producers, such as aflatoxins produced during the secondary metabolism of Aspergillus flavus, A. parasiticus and A. nomius. Aflatoxins, mainly aflatoxin B1, are directly associated with liver cancer in human beings. This paper is aimed at evaluating the presence of aflatoxin B1 in a few vegetable drugs, dried plant extracts and industrialized products traded in 2010 in the city of Belo Horizonte, State of Minas Gerais, Brazil. The method used for the quantification of aflatoxin B1 was based on extraction through acetone:water (85:15), immunoaffinity column purification followed by separation and detection in high efficiency liquid chromatography. Under the conditions of analysis, the Limits of Detection and Quantification were 0.6 µg kg-1 and 1.0 µg kg-1 respectively. The complete sets of analyses were carried out in duplicate. Aflatoxin B1 was noticed in a single sample (< 1.0 µg kg-1). The results revealed low aflatoxin B1 contamination in the products under analysis. However, it is required to establish a broad monitoring program in order to obtain additional data and check up on the actual extension of contamination. PMID:24031973

  1. Phosphorylation controls a dual-function polybasic nuclear localization sequence in the adapter protein SH2B1β to regulate its cellular function and distribution.

    PubMed

    Maures, Travis J; Su, Hsiao-Wen; Argetsinger, Lawrence S; Grinstein, Sergio; Carter-Su, Christin

    2011-05-01

    An intriguing question in cell biology is what targets proteins to, and regulates their translocation between, specific cellular locations. Here we report that the polybasic nuclear localization sequence (NLS) required for nuclear entry of the adapter protein and candidate human obesity gene product SH2B1β, also localizes SH2B1β to the plasma membrane (PM), most probably via electrostatic interactions. Binding of SH2B1β to the PM also requires its dimerization domain. Phosphorylation of serine residues near this polybasic region, potentially by protein kinase C, releases SH2B1β from the PM and enhances nuclear entry. Release of SH2B1β from the PM and/or nuclear entry appear to be required for SH2B1β enhancement of nerve growth factor (NGF)-induced expression of urokinase plasminogen activator receptor gene and neurite outgrowth of PC12 cells. Taken together, our results provide strong evidence that the polybasic NLS region of SH2B1 serves the dual function of localizing SH2B1 to both the nucleus and the PM, the latter most probably through electrostatic interactions that are enhanced by SH2B1β dimerization. Cycling between the different cellular compartments is a consequence of the phosphorylation and dephosphorylation of serine residues near the NLS and is important for physiological effects of SH2B1, including NGF-induced gene expression and neurite outgrowth.

  2. EphB1 and EphB2 intracellular domains regulate the formation of the corpus callosum and anterior commissure.

    PubMed

    Robichaux, Michael A; Chenaux, George; Ho, Hsin-Yi Henry; Soskis, Michael J; Greenberg, Michael E; Henkemeyer, Mark; Cowan, Christopher W

    2016-04-01

    The two cortical hemispheres of the mammalian forebrain are interconnected by major white matter tracts, including the corpus callosum (CC) and the posterior branch of the anterior commissure (ACp), that bridge the telencephalic midline. We show here that the intracellular signaling domains of the EphB1 and EphB2 receptors are critical for formation of both the ACp and CC. We observe partial and complete agenesis of the corpus callosum, as well as highly penetrant ACp misprojection phenotypes in truncated EphB1/2 mice that lack intracellular signaling domains. Consistent with the roles for these receptors in formation of the CC and ACp, we detect expression of these receptors in multiple brain regions associated with the formation of these forebrain structures. Taken together, our findings suggest that a combination of forward and reverse EphB1/2 receptor-mediated signaling contribute to ACp and CC axon guidance.

  3. Evaluation of particulate air samplers for airborne aflatoxin B1

    SciTech Connect

    Silas, J.C.; Harrison, M.A.; Carpenter, J.A.

    1986-01-01

    Five air samplers (Millipore, all-glass impinger, centrifugal, Andersen, and absorbent cotton) were evaluated for their ability to collect airborne grain particles contaminated with aflatoxin B1. Corn dust containing 100 micrograms aflatoxin B1/g was aerosolized within a containment system. Each device sampled 100 I air, thus exchanging the air in the chamber two times. Aflatoxin B1 was extracted from all sampling matrices and was detected and quantitated with thin-layer chromatography and scanning fluorodensitometry. The highest efficiency was obtained with the Millipore sampler, while the efficiencies of the centrifugal and the cotton samplers were almost identical. Efficiency of an Andersen was less, with no toxin recovered from an all-glass impinger. Measurement of particle size was accomplished with the Andersen sampler.

  4. B1-Metallo-beta-Lactamases: Where do we stand?

    PubMed Central

    Mojica, Maria F.; Bonomo, Robert A.; Fast, Walter

    2015-01-01

    Metallo-beta-Lactamases (MBLs) are class B β-lactamases that hydrolyze almost all clinically-available β-lactam antibiotics. MBLs feature the distinctive αβ/βα sandwich fold of the metallo-hydrolase / oxidoreductase superfamily and possess a shallow active-site groove containing one or two divalent zinc ions, flanked by flexible loops. According to sequence identity and zinc ion dependence, MBLs are classified into three subclasses (B1, B2 and B3), of which the B1 subclass enzymes have emerged as the most clinically significant. Differences among the active site architectures, the nature of zinc ligands, and the catalytic mechanisms have limited the development of a common inhibitor. In this review, we will describe the molecular epidemiology and structural studies of the most prominent representatives of class B1 MBLs (NDM-1, IMP-1 and VIM-2) and describe the implications for inhibitor design to counter this growing clinical threat. PMID:26424398

  5. Hyperoxic gassing with Tiron enhances bradykinin-induced endothelium-dependent and EDH-type relaxation through generation of hydrogen peroxide.

    PubMed

    Wong, Pui San; Roberts, Richard E; Randall, Michael D

    2015-01-01

    Oxygenation with 95%O2 is routinely used in organ bath studies. However, hyperoxia may affect tissue responses, particularly in studies which involve reactive oxygen species (ROS). Here, the effects of the antioxidant, Tiron, were investigated under different gassing conditions in the porcine isolated coronary artery (PCA). Distal PCAs from male and female pigs were mounted in a wire myograph gassed with either 95%O2/5%CO2 or 95% air/5%CO2 and pre-contracted with U46619. Concentration-response curves to bradykinin were constructed in the presence of Tiron (1mM), a cell permeable superoxide scavenger and catalase (1000Uml(-1)) to breakdown H2O2. The H2O2 level in Krebs'-Henseleit solution was detected using Amplex Red. Bradykinin produced concentration-dependent vasorelaxations in male and female PCAs when gassed with either 95%O2 or air, with no differences in the Rmax or EC50. Tiron increased the potency of bradykinin only when gassed with 95%O2 in PCAs from both sexes. At 95%O2, catalase prevented the leftward shift caused by Tiron in both sexes indicating that catalase prevented the formation of H2O2 by Tiron. In female PCAs, addition of catalase to Tiron significantly reduced the Rmax. In the EDH-type response (using L-NAME and indomethacin), Tiron enhanced the potency of the bradykinin-induced vasorelaxation when gassed with 95%O2 in PCAs from both sexes. Biochemical analysis using Amplex Red demonstrated that H2O2 was generated in Krebs'-Henseleit solution when gassed with 95%O2, but not with air. Therefore, hyperoxic gassing conditions could alter the environment generating superoxide within the Krebs'-Henseleit buffer, which may, in turn, influence the in vitro pharmacological responses.

  6. Nucleocytoplasmic shuttling of the adapter protein SH2B1beta (SH2-Bbeta) is required for nerve growth factor (NGF)-dependent neurite outgrowth and enhancement of expression of a subset of NGF-responsive genes.

    PubMed

    Maures, Travis J; Chen, Linyi; Carter-Su, Christin

    2009-07-01

    The adapter protein SH2B1 (SH2-B, PSM) is recruited to multiple ligand-activated receptor tyrosine kinases, including the receptors for nerve growth factor (NGF), insulin, and IGF-I as well as the cytokine receptor-associated Janus kinase family kinases. In this study, we examine SH2B1's function in NGF signaling. We show that depleting endogenous SH2B1 using short hairpin RNA against SH2B1 inhibits NGF-dependent neurite outgrowth, but not NGF-mediated phosphorylation of Akt or ERKs 1/2. SH2B1 has been hypothesized to localize and function at the plasma membrane. We identify a nuclear localization signal within SH2B1 and show that it is required for nuclear translocation of SH2B1beta. Mutation of the nuclear localization signal has no effect on NGF-induced activation of TrkA and ERKs 1/2 but prevents SH2B1beta from enhancing NGF-induced neurite outgrowth. Disruption of SH2B1beta nuclear import also prevents SH2B1beta from enhancing NGF-induced transcription of genes important for neuronal differentiation, including those encoding urokinase plasminogen activator receptor, and matrix metalloproteinases 3 and 10. Disruption of SH2B1beta nuclear export by mutation of its nuclear export sequence similarly prevents SH2B1beta enhancement of NGF-induced transcription of those genes. Nuclear translocation of the highly homologous family member SH2B2(APS) was not observed. Together, these data suggest that rather than simply acting as an adapter protein linking signaling proteins to the activated TrkA receptor at the plasma membrane, SH2B1beta must shuttle between the plasma membrane and nucleus to function as a critical component of NGF-induced gene expression and neuronal differentiation.

  7. The Ras-related protein Cdc42Hs and bradykinin promote formation of peripheral actin microspikes and filopodia in Swiss 3T3 fibroblasts.

    PubMed Central

    Kozma, R; Ahmed, S; Best, A; Lim, L

    1995-01-01

    The Ras-related protein Cdc42 plays a role in yeast cell budding and polarity. Two related proteins, Rac1 and RhoA, promote formation in mammalian cells of membrane ruffles and stress fibers, respectively, which contain actin microfilaments. We now show that microinjection of the related human Cdc42Hs into Swiss 3T3 fibroblasts induced the formation of peripheral actin microspikes, determined by staining with phalloidin. A proportion of these microspikes was found to be components of filopodia, as analyzed by time-lapse phase-contrast microscopy. The formation of filopodia was also found to be promoted by Cdc42Hs microinjection. This was followed by activation of Rac1-mediated membrane ruffling. Treatment with bradykinin also promoted formation of microspikes and filopodia as well as subsequent effects similar to that seen upon Cdc42Hs microinjection. These effects of bradykinin were specifically inhibited by prior microinjection of dominant negative Cdc42HsT17N, suggesting that bradykinin acts by activating cellular Cdc42Hs. Since filopodia have been ascribed an important sensory function in fibroblasts and are required for guidance of neuronal growth cones, these results indicate that Cdc42Hs plays an important role in determining mammalian cell morphology. PMID:7891688

  8. Leptin induces CYP1B1 expression in MCF-7 cells through ligand-independent activation of the ERα pathway

    SciTech Connect

    Khanal, Tilak; Kim, Hyung Gyun; Do, Minh Truong; Choi, Jae Ho; Won, Seong Su; Kang, Wonku; Chung, Young Chul; Jeong, Tae Cheon; Jeong, Hye Gwang

    2014-05-15

    Leptin, a hormone with multiple biological actions, is produced predominantly by adipose tissue. Among its functions, leptin can stimulate tumour cell growth. Oestrogen receptor α (ERα), which plays an essential role in breast cancer development, can be transcriptionally activated in a ligand-independent manner. In this study, we investigated the effect of leptin on CYP1B1 expression and its mechanism in breast cancer cells. Leptin induced CYP1B1 protein, messenger RNA expression and promoter activity in ERα-positive MCF-7 cells but not in ERα-negative MDA-MB-231 cells. Additionally, leptin increased 4-hydroxyoestradiol in MCF-7 cells. Also, ERα knockdown by siRNA significantly blocked the induction of CYP1B1 expression by leptin, indicating that leptin induced CYP1B1 expression via an ERα-dependent mechanism. Transient transfection with CYP1B1 deletion promoter constructs revealed that the oestrogen response element (ERE) plays important role in the up-regulation of CYP1B1 by leptin. Furthermore, leptin stimulated phosphorylation of ERα at serine residues 118 and 167 and increased ERE-luciferase activity, indicating that leptin induced CYP1B1 expression by ERα activation. Finally, we found that leptin activated ERK and Akt signalling pathways, which are upstream kinases related to ERα phosphorylation induced by leptin. Taken together, our results indicate that leptin-induced CYP1B1 expression is mediated by ligand-independent activation of the ERα pathway as a result of the activation of ERK and Akt in MCF-7 cells. - Highlights: • Leptin increased 4-hydroxyoestradiol in MCF-7 breast cancer cells. • Leptin activated ERK and Akt kinases related to ERα phosphorylation. • Leptin induces phosphorylation of ERα at serine residues 118 and 167. • Leptin induces ERE-luciferase activity.

  9. 78 FR 699 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-04

    ... Proposed Issuance of Letter of Offer Pursuant to Section 36(b)(1) of the Arms Export Control Act, as... Control Act. (iii) Description and Quantity or Quantities of Articles or Services under Consideration for... ground moving target indicator. The ground segment includes a mission control element and a launch...

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    Federal Register 2010, 2011, 2012, 2013, 2014

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  11. 26 CFR 1.7702B-1 - Consumer protection provisions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

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  12. In vivo formation of N-acyl-fumonisin B1

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fumonisins are fungal toxins found in corn and in corn-based foods. Fumonisin B1 (FB1) is the most common and is toxic to animals, causes cancer in rodents, and is a suspected risk factor for cancer and birth defects in humans. The hydrolyzed form of FB1 (HFB1) also occurs in foods and is metabolize...

  13. 26 CFR 54.4980B-1 - COBRA in general.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... for topics not addressed in §§ 54.4980B-1 through 54.4980B-10? A-2: For purposes of section 4980B, for topics relating to the COBRA continuation coverage requirements of section 4980B that are not...

  14. 78 FR 15004 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

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  1. 78 FR 62590 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

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  4. 26 CFR 1.669(b)-1 - Information requirements.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Beginning Before January 1, 1969 § 1.669(b)-1 Information requirements. The election of a beneficiary who is... unless the beneficiary, at or before the time the election is made, supplies, in a letter addressed to.... person for each of the preceding taxable years, on the last day of which an amount is deemed...

  5. 75 FR 48947 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

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    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of a section...

  6. 75 FR 11865 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-12

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of a section...

  7. 75 FR 30787 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-02

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of a section...

  8. 76 FR 27022 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-10

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, Department of Defense. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified...

  9. 76 FR 43659 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-21

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security Cooperation Agency. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text...

  10. 76 FR 37078 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-24

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security Cooperation Agency. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text...

  11. 75 FR 23247 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-03

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of a section...

  12. 75 FR 69957 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-16

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security Cooperation Agency. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text...

  13. 75 FR 69938 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-16

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, Department of Defense. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified...

  14. 76 FR 40703 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-11

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security Cooperation Agency. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text...

  15. 78 FR 36534 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-18

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... security of the United States, by helping to improve the security of a friendly country which has been,...

  16. 75 FR 69931 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-16

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, Department of Defense. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified...

  17. 78 FR 42758 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-17

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security Cooperation Agency. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of... $250 million. This proposed sale will contribute to the foreign policy and national security of...

  18. 77 FR 60391 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-03

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of a section...

  19. 75 FR 60424 - 36(b)(1) Arms Sales Notifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-30

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notifications AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of two section...

  20. 75 FR 61440 - 36(b)(1) Arms Sales Notifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-05

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notifications AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of three...

  1. 75 FR 48646 - 36(b)(1) Arms Sales Notifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-11

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notifications AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of three...

  2. 75 FR 69926 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-16

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, Department of Defense. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified...

  3. 75 FR 74011 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-30

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security Cooperation Agency. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text...

  4. 75 FR 4785 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-29

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of a section...

  5. 75 FR 47275 - 36(b)(1) Arms Sales Notifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-05

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notifications AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of two section...

  6. 75 FR 76408 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-08

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, Department of Defense. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified...

  7. 75 FR 76412 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-08

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, Department of Defense. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified...

  8. 75 FR 76415 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-08

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, Department of Defense. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified...

  9. 76 FR 107 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-03

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, Department of Defense. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified...

  10. 75 FR 41820 - 36(b)(1) Arms Sales Notifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-19

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notifications AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of five section...

  11. 75 FR 69960 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-16

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security Cooperation Agency. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text...

  12. 75 FR 69922 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-16

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, Department of Defense. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified...

  13. 76 FR 103 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-03

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, Department of Defense. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified...

  14. 76 FR 30676 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-26

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, Department of Defense. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified...

  15. 75 FR 74014 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-30

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security Cooperation Agency. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text...

  16. 75 FR 27314 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-14

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of a section...

  17. 75 FR 76418 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-08

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security Cooperation Agency. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text...

  18. 77 FR 60384 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-03

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of a section...

  19. 78 FR 41040 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-09

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... sale will contribute to the foreign policy and national security of the United States by helping to improve the security of a friendly country that has been, and continues to be, an important force...

  20. 77 FR 71401 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-30

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... proposed sale will contribute to the foreign policy and national security of the United States by helping to improve the security of a friendly country that has been, and continues to be, an important...

  1. 75 FR 69953 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-16

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security Cooperation Agency. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text...

  2. 76 FR 29212 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-20

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, Department of Defense. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified...

  3. 75 FR 29998 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-28

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of a section...

  4. 76 FR 17111 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-28

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security Cooperation Agency. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text...

  5. 76 FR 27026 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-10

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, Department of Defense. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified...

  6. 75 FR 69971 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-16

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security Cooperation Agency. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text...

  7. 77 FR 14767 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-13

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security Cooperation Agency. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of.... This proposed sale will contribute to the foreign policy and national security of the United States...

  8. 76 FR 37075 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-24

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security Cooperation Agency. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text...

  9. 78 FR 50045 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-16

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... regional security objectives and interoperability with the United States. This proposed sale is...

  10. 76 FR 37071 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-24

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security Cooperation Agency. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text...

  11. 77 FR 60387 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-03

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of a section...

  12. 75 FR 5971 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-05

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of six section...

  13. 77 FR 40028 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-06

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security Cooperation Agency. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of... contribute to the foreign policy and national security of the United States by helping to improve...

  14. 75 FR 69947 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-16

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, Department of Defense. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified...

  15. 76 FR 30670 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-26

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, Department of Defense. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified...

  16. 75 FR 81993 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-29

    ...(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security Cooperation Agency. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of a section 36(b... Law 104-164 dated 21 July 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English, DSCA/DBO/CFM,...

  17. 76 FR 8716 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-15

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of a section...

  18. 76 FR 18726 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-05

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, DoD ACTION: Notice SUMMARY: The Department of Defense is publishing the unclassified text of a section 36(b... Law 104-164 dated 21 July 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English, DSCA/DBO/CFM,...

  19. 75 FR 107 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-04

    ... No: E9-31159] DEPARTMENT OF DEFENSE Office of the Secretary [Transmittal Nos. 09-67 and 09-72] 36(b...: The Department of Defense is publishing the unclassified text of two section 36(b)(1) arms sales... INFORMATION CONTACT: Ms. B. English, DSCA/DBO/CFM, (703) 601-3740. SUPPLEMENTARY INFORMATION: The...

  20. 76 FR 18731 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-05

    ... Office of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of a section 36(b... Law 104-164 dated 21 July 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English, DSCA/DBO/CFM,...

  1. 75 FR 9182 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-01

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of a section 36(b... July 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English, DSCA/DBO/CFM, (703) 601-3740....

  2. 75 FR 51445 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-20

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency, DoD. ACTION: Notice. SUMMARY: The Department of Defense is publishing the unclassified text of a section 36(b... July 1996. FOR FURTHER INFORMATION CONTACT: Ms. B. English, DSCA/DBO/CFM, (703) 601-3740....

  3. 76 FR 55651 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-08

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Department of Defense, Defense Security... Representatives, Transmittals 11-33 with attached transmittal, policy justification, and Sensitivity of Technology... installation of 4 AN/USQ-78B Acoustic Processor Technology Refresh (APTR), 4 AN/ASQ- 227 Aircraft...

  4. 78 FR 50047 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-16

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... for Purchase: 19 Mobile Troposcatter Radio Systems, 10 Mobile Microwave Radio Systems, spare and... Technology Contained in the Defense Article or Defense Services Proposed to be Sold: None (viii) Date...

  5. 78 FR 50043 - 36(b)(1) Arms Sales Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-16

    ... of the Secretary 36(b)(1) Arms Sales Notification AGENCY: Defense Security Cooperation Agency... Representatives, Transmittals 12-67 with attached transmittal, policy justification, and Sensitivity of Technology... Illuminator Radars, 216 MIM-23P HAWK Tactical Missiles, 2 Mobile Battalion Operation Centers (BOC), 3 HAWK...

  6. Role of Lamin B1 in Chromatin Instability

    PubMed Central

    Butin-Israeli, Veronika; Adam, Stephen A.; Jain, Nikhil; Otte, Gabriel L.; Neems, Daniel; Wiesmüller, Lisa; Berger, Shelly L.

    2014-01-01

    Nuclear lamins play important roles in the organization and structure of the nucleus; however, the specific mechanisms linking lamin structure to nuclear functions are poorly defined. We demonstrate that reducing nuclear lamin B1 expression by short hairpin RNA-mediated silencing in cancer cell lines to approximately 50% of normal levels causes a delay in the cell cycle and accumulation of cells in early S phase. The S phase delay appears to be due to the stalling and collapse of replication forks. The double-strand DNA breaks resulting from replication fork collapse were inefficiently repaired, causing persistent DNA damage signaling and the assembly of extensive repair foci on chromatin. The expression of multiple factors involved in DNA replication and repair by both nonhomologous end joining and homologous repair is misregulated when lamin B1 levels are reduced. We further demonstrate that lamin B1 interacts directly with the promoters of some genes associated with DNA damage response and repair, including BRCA1 and RAD51. Taken together, the results suggest that the maintenance of lamin B1 levels is required for DNA replication and repair through regulation of the expression of key factors involved in these essential nuclear functions. PMID:25535332

  7. Nicotine impairs cyclooxygenase-2-dependent kinin-receptor-mediated murine airway relaxations

    SciTech Connect

    Xu, Yuan Cardell, Lars-Olaf

    2014-02-15

    Introduction: Cigarette smoke induces local inflammation and airway hyperreactivity. In asthmatics, it worsens the symptoms and increases the risk for exacerbation. The present study investigates the effects of nicotine on airway relaxations in isolated murine tracheal segments. Methods: Segments were cultured for 24 h in the presence of vehicle, nicotine (10 μM) and/or dexamethasone (1 μM). Airway relaxations were assessed in myographs after pre-contraction with carbachol (1 μM). Kinin receptors, cyclooxygenase (COX) and inflammatory mediator expressions were assessed by real-time PCR and confocal-microscopy-based immunohistochemistry. Results: The organ culture procedure markedly increased bradykinin- (selective B{sub 2} receptor agonist) and des-Arg{sup 9}-bradykinin- (selective B{sub 1} receptor agonist) induced relaxations, and slightly increased relaxation induced by isoprenaline, but not that induced by PGE{sub 2}. The kinin receptor mediated relaxations were epithelium-, COX-2- and EP2-receptor-dependent and accompanied by drastically enhanced mRNA levels of kinin receptors, as well as inflammatory mediators MCP-1 and iNOS. Increase in COX-2 and mPGES-1 was verified both at mRNA and protein levels. Nicotine selectively suppressed the organ-culture-enhanced relaxations induced by des-Arg{sup 9}-bradykinin and bradykinin, at the same time reducing mPGES-1 mRNA and protein expressions. α7-nicotinic acetylcholine receptor inhibitors α-bungarotoxin and MG624 both blocked the nicotine effects on kinin B{sub 2} receptors, but not those on B{sub 1}. Dexamethasone completely abolished kinin-induced relaxations. Conclusion: It is tempting to conclude that a local inflammatory process per se could have a bronchoprotective component by increasing COX-2 mediated airway relaxations and that nicotine could impede this safety mechanism. Dexamethasone further reduced airway inflammation together with relaxations. This might contribute to the steroid resistance seen in

  8. Effects of Aflatoxin B1 and Fumonisin B1 on the Viability and Induction of Apoptosis in Rat Primary Hepatocytes

    PubMed Central

    Ribeiro, Deise H. B.; Ferreira, Fabiane L.; da Silva, Valéria N.; Aquino, Simone; Corrêa, Benedito

    2010-01-01

    The present study evaluated the effect of aflatoxin B1 (AFB1) and fumonisin B1 (FB1) either alone, or in association, on rat primary hepatocyte cultures. Cell viability was assessed by flow cytometry after propidium iodine intercalation. DNA fragmentation and apoptosis were assessed by agarose gel electrophoresis and acridine orange and ethidium bromide staining. At the concentrations of AFB1 and FB1 used, the toxins did not decrease cell viability, but did induce apoptosis in a concentration and time-dependent manner. PMID:20480051

  9. A new structurally atypical bradykinin-potentiating peptide isolated from Crotalus durissus cascavella venom (South American rattlesnake).

    PubMed

    Lopes, Denise M; Junior, Norberto E G; Costa, Paula P C; Martins, Patrícia L; Santos, Cláudia F; Carvalho, Ellaine D F; Carvalho, Maria D F; Pimenta, Daniel C; Cardi, Bruno A; Fonteles, Manassés C; Nascimento, Nilberto R F; Carvalho, Krishnamurti M

    2014-11-01

    Venom glands of some snakes synthesize bradykinin-potentiating peptides (BPP's) which increase bradykinin-induced hypotensive effect and decrease angiotensin I vasopressor effect by angiotensin-converting enzyme (ACE) inhibition. The present study shows a new BPP (BPP-Cdc) isolated from Crotalus durissus cascavella venom: Pro-Asn-Leu-Pro-Asn-Tyr-Leu-Gly-Ile-Pro-Pro. Although BPP-Cdc presents the classical sequence IPP in the C-terminus, it has a completely atypical N-terminal sequence, which shows very low homology with all other BPPs isolated to date. The pharmacological effects of BPP-Cdc were compared to BBP9a from Bothrops jararaca and captopril. BPP-Cdc (1 μM) significantly increased BK-induced contractions (BK; 1 μM) on the guinea pig ileum by 267.8% and decreased angiotensin I-induced contractions (AngI; 10 nM) by 62.4% and these effects were not significantly different from those of BPP9a (1 μM) or captopril (200 nM). Experiments with 4-week hypertensive 2K-1C rats show that the vasopressor effect of AngI (10 ng) was decreased by 50 μg BPP-Cdc (69.7%), and this result was similar to that obtained with 50 μg BPP9a (69.8%). However, the action duration of BPP-Cdc (60 min) was 2 times greater than that of BPP-9a (30 min). On the other hand, the hypotensive effect of BK (250 ng) was significantly increased by 176.6% after BPP-Cdc (50 μg) administration, value 2.5 times greater than that obtained with BPP9a administered at the same doses (71.4%). In addition, the duration of the action of BPP-Cdc (120 min) was also at least 4 times greater than that of BPP-9a (30 min). Taken together, these results suggest that BPP-Cdc presents more selective action on arterial blood system than BPP9a. Besides the inhibition of ACE, it may present other mechanisms of action yet to be elucidated.

  10. Sema4D, the ligand for Plexin B1, suppresses c-Met activation and migration and promotes melanocyte survival and growth

    PubMed Central

    Soong, Joanne; Chen, Yulin; Shustef, Elina; Scott, Glynis

    2011-01-01

    Semaphorins are secreted and membrane bound proteins involved in neural pathfinding, organogenesis, and tumor progression, through Plexin and neuropilins receptors. We recently reported that Plexin B1, the Semaphorin 4D receptor, is a tumor suppressor protein for melanoma, in part, through inhibition of the oncogenic c-Met tyrosine kinase receptor. In this report we show that Sema4D is a protective paracrine factor for normal human melanocyte survival in response to ultraviolet irradiation, that it stimulates proliferation, and regulates the activity of the c-Met receptor. c-Met receptor signaling stimulates melanocyte migration, in part through down-regulation of the cell adhesion molecule E-cadherin. Sema4D suppressed activation of c-Met in response to its ligand hepatocyte growth factor (HGF), and partially blocked the suppressive effects of HGF on E-cadherin expression in melanocytes and HGF-dependent migration. These data demonstrate a role for Plexin B1 in maintenance of melanocyte survival and proliferation in the skin, and suggest that Semaphorin 4D and Plexin B1 act cooperatively with HGF and c-Met to regulate c-Met dependent effects in human melanocytes. Because our data show that Plexin B1 is profoundly down-regulated by UVB in melanocytes, loss of Plexin B1 may accentuate HGF dependent effects on melanocytes, including melanocyte migration. PMID:22189792

  11. ErbB1-4-dependent EGF/neuregulin signals and their cross talk in the central nervous system: pathological implications in schizophrenia and Parkinson's disease

    PubMed Central

    Iwakura, Yuriko; Nawa, Hiroyuki

    2013-01-01

    Ligands for ErbB1-4 receptor tyrosine kinases, such as epidermal growth factor (EGF) and neuregulins, regulate brain development and function. Thus, abnormalities in their signaling are implicated in the etiology or pathology of schizophrenia and Parkinson's disease. Among the ErbB receptors, ErbB1, and ErbB4 are expressed in dopamine and GABA neurons, while ErbB1, 2, and/or 3 are mainly present in oligodendrocytes, astrocytes, and their precursors. Thus, deficits in ErbB signaling might contribute to the neurological and psychiatric diseases stemming from these cell types. By incorporating the latest cancer molecular biology as well as our recent progress, we discuss signal cross talk between the ErbB1-4 subunits and their neurobiological functions in each cell type. The potential contribution of virus-derived cytokines (virokines) that mimic EGF and neuregulin-1 in brain diseases are also discussed. PMID:23408472

  12. Bradykinin modulates potassium and calcium currents in neuroblastoma hybrid cells via different pertussis toxin-insensitive pathways.

    PubMed

    Wilk-Blaszczak, M A; Gutowski, S; Sternweis, P C; Belardetti, F

    1994-01-01

    In NG108-15 cells, bradykinin (BK) activates a potassium current (IK,BK) and inhibits the voltage-dependent calcium current (ICa,V). BK also stimulates a phosphatidylinositol-specific phospholipase C (PI-PLC). The subsequent release of inositol 1,4,5-trisphosphate and increase in intracellular calcium contribute to IK,BK, through activation of a calcium-dependent potassium current. In membranes from these cells, stimulation of PI-PLC by BK is mediated by Gq and/or G11, two homologous, pertussis toxin-insensitive G proteins. Here, we have investigated the role of Gq/11 in the electrical responses to BK. GTP gamma S mimicked and occluded both actions of BK, and both effects were insensitive to pertussis toxin. Perfusion of an anti-Gq/11 alpha antibody into the pipette suppressed IK,BK, but not the inhibition of ICa,V by BK. Thus, BK couples to IK,BK via Gq/11, but coupling to ICa,V is most likely via a different, pertussis toxin-insensitive G protein.

  13. The effects of captopril on cardiac regression, blood pressure and bradykinin components in diabetic Wistar Kyoto rats.

    PubMed

    Sharma, J N; Kesavarao, U

    2011-01-01

    The present study examined the left ventricular wall thickness (LVWT), total urinary kallikrein, total plasma kininogen and mean arterial blood pressure (MABP) in diabetic and non-diabetic Wistar Kyoto (WKY) rats. The MABP was significantly raised (P<0.01) in diabetic WKY rats compared to the respective controls. The LVWT was also significantly (P<0.01) increased in diabetic WKY rats than that of control WKY rats. The mean total urinary kallikrein level and the mean total plasma kininogen level were higher (P<0.01) in diabetic WKY rats, when these rats were treated with captopril (40 mg/kg and 80 mg/kg) against the mean value obtained from control WKY rats. In conclusion, this investigation suggests that diabetes induced in these rats can cause hypertension, increased LVWT and changes in the BK-forming components. Captopril treatment caused reduction in MABP, regression of LVWT and alterations in bradykinin (BK)-forming components. The possible significance of these observations is discussed.

  14. ErbB2, but not ErbB1, reinitiates proliferation and induces luminal repopulation in epithelial acini

    SciTech Connect

    Muthuswamy, Senthil K; Li, Dongmei; Lelievre, Sophie; Bissell, Mina J; Brugge, Joan S

    2001-08-08

    Both ErbB1 and ErbB2 are overexpressed or amplified in breast tumors. To examine the effects of activating ErbB receptors in a context that mimics polarized epithelial cells in vivo, we activated ErbB1 and ErbB2 homodimers in preformed, growth-arrested mammary acini cultured in three-dimensional basement membrane gels. Activation of ErbB2, but not that of ErbB1, led to a reinitiation of cell proliferation and altered the properties of mammary acinar structures. These altered structures share several properties with early-stage tumors, including a loss of proliferative suppression, an absence of lumen, retention of the basement membrane and a lack of invasive properties. ErbB2 activation also disrupted tight junctions and the cell polarity of polarized epithelia, whereas ErbB1 activation did not have any effect. Our results indicate that ErbB receptors differ in their ability to induce early stages of mammary carcinogenesis in vitro and this three-dimensional model system can reveal biological activities of oncogenes that cannot be examined in vitro in standard transformation assays.

  15. Photophysics and photochemistry of aflatoxins B1 and B2.

    PubMed

    Netto-Ferreira, J C; Heyne, B; Scaiano, J C

    2011-10-01

    Aflatoxins are mycotoxins produced by fungi of the genus Aspergillus, which is widely spread in the tropics and subtropics. To date, aflatoxin phototoxicity has been recognized, but the mechanism responsible for this phototoxicity has not been fully characterized. In the present paper, nanosecond laser flash photolysis studies allowed us to elucidate the photochemical processes undergone by two mycotoxins, namely aflatoxin B(1) and B(2), upon UV irradiation. In brief, photolysis (308 nm) of the aflatoxins leads to intersystem crossing, giving rise to their triplet excited state. The triplet state can readily be quenched by indole and hydroquinone, and also by molecular oxygen yielding singlet oxygen (singlet oxygen quantum yields of 0.51 and 0.59 were found for aflatoxin B(1) and B(2), respectively). In addition, our data indicate the ability of the two aflatoxins to photoionize upon 248 nm excitation. The photoionization quantum yield for aflatoxin B(1) and B(2) have been estimated to be 0.11 and 0.29, respectively.

  16. DAX1/NR0B1 was expressed during mammalian gonadal development and gametogenesis before it was recruited to the eutherian X chromosome.

    PubMed

    Stickels, Robert; Clark, Kevin; Heider, Thomas N; Mattiske, Deidre M; Renfree, Marilyn B; Pask, Andrew J

    2015-01-01

    The nuclear receptor subfamily 0, group B, member 1 (NR0B1) gene is an orphan nuclear receptor that is X-linked in eutherian mammals and plays a critical role in the establishment and function of the hypothalamic-pituitary-adrenal-gonadal axis. Duplication or overexpression of NR0B1 in eutherian males causes male to female sex reversal, and mutation and deletions of NR0B1 cause testicular defects. Thus, gene dosage is critical for the function of NR0B1 in normal gonadogenesis. However, NR0B1 is autosomal in all noneutherian vertebrates, including marsupials and monotreme mammals, and two active copies of the gene are compatible with both male and female gonadal development. In the current study, we examined the evolution and expression of autosomal NR0B1 during gonadal development in a marsupial (the tammar wallaby) as compared to the role of its X-linked orthologues in a eutherian (the mouse). We show that NR0B1 underwent rapid evolutionary change when it relocated from its autosomal position in the nonmammalian vertebrates, monotremes, and marsupials to an X-linked location in eutherian mammals. Despite the acquisition of a novel genomic location and a unique N-terminal domain, NR0B1 protein distribution was remarkably similar between mice and marsupials both throughout gonadal development and during gamete formation. A conserved accumulation of NR0B1 protein was observed in developing oocytes, where its function appears to be critical in the early embryo, prior to zygotic genome activation. Together these findings suggest that NR0B1 had a conserved role in gonadogenesis that existed long before it moved to the X chromosome and despite undergoing significant evolutionary change.

  17. Estrogen and Cytochrome P450 1B1 Contribute to Both Early- and Late-Stage Head and Neck Carcinogenesis

    PubMed Central

    Shatalova, Ekaterina G.; Klein-Szanto, Andres J.P.; Devarajan, Karthik; Cukierman, Edna; Clapper, Margie L.

    2010-01-01

    Squamous cell carcinoma of the head and neck (HNSCC) is the sixth most common type of cancer in the U.S. The goal of this study was to evaluate the contribution of estrogens to the development of HNSCCs. Various cell lines derived from early- and late-stage head and neck lesions were used to: characterize the expression of estrogen synthesis and metabolism genes, including cytochrome P450 (CYP)1B1, examine the effect of estrogen on gene expression and evaluate the role of CYP1B1 and/or estrogen in cell motility, proliferation and apoptosis. Estrogen metabolism genes (CYP1B1, CYP1A1, catechol-o-methyltransferase, UDP-glucuronosyltransferase 1A1, and glutathione-S-transferase P1) and estrogen receptor (ER)β were expressed in cell lines derived from both premalignant (MSK-Leuk1) and malignant (HNSCC) lesions. Exposure to estrogen induced CYP1B1 2.3 to 3.6 fold relative to vehicle-treated controls (P=0.0004) in MSK-Leuk1 cells but not in HNSCC cells. CYP1B1 knockdown by shRNA reduced the migration and proliferation of MSK-Leuk1 cells by 57% and 45%, respectively. Exposure of MSK-Leuk1 cells to estrogen inhibited apoptosis by 26%, while supplementation with the antiestrogen fulvestrant restored estrogen-dependent apoptosis. Representation of the estrogen pathway in human head and neck tissues from 128 patients was examined using tissue microarrays. The majority of the samples exhibited immunohistochemical staining for ERβ (91.9%), CYP1B1 (99.4%) and 17β-estradiol (88.4%). CYP1B1 and ERβ were elevated in HNSCCs relative to normal epithelium (P=0.024 and 0.008, respectively). These data provide novel insight into the mechanisms underlying head and neck carcinogenesis and facilitate the identification new targets for chemopreventive intervention. PMID:21205741

  18. Regulation of prostaglandin EP1 and EP4 receptor signaling by carrier-mediated ligand reuptake

    PubMed Central

    Chi, Yuling; Suadicani, Sylvia O; Schuster, Victor L

    2014-01-01

    After synthesis and release from cells, prostaglandin E2 (PGE2) undergoes reuptake by the prostaglandin transporter (PGT), followed by cytoplasmic oxidation. Although genetic inactivation of PGT in mice and humans results in distinctive phenotypes, and although experiments in localized environments show that manipulating PGT alters downstream cellular events, a direct mechanistic link between PGT activity and PGE2 (EP) receptor activation has not been made. Toward this end, we created two reconstituted systems to examine the effect of PGT expression on PGE2 signaling via two of its receptors (EP1 and EP4). In human embryonic kidney cells engineered to express the EP1 receptor, exogenous PGE2 induced a dose-dependent increase in cytoplasmic Ca2+. When PGT was expressed at the plasma membrane, the PGE2 dose–response curve was right-shifted, consistent with reduction in cell surface PGE2 availability; a potent PGT inhibitor acutely reversed this shift. When bradykinin was used to induce endogenous PGE2 release, PGT expression similarly induced a reduction in Ca2+ responses. In separate experiments using Madin–Darby Canine Kidney cells engineered to express the PGE2 receptor EP4, bradykinin again induced autocrine PGE2 signaling, as judged by an abrupt increase in intracellular cAMP. As in the EP1 experiments, expression of PGT at the plasma membrane caused a reduction in bradykinin-induced cAMP accumulation. Pharmacological concentrations of exogenous PGE2 induced EP4 receptor desensitization, an effect that was mitigated by PGT. Thus, at an autocrine/paracrine level, plasma membrane PGT regulates PGE2 signaling by decreasing ligand availability at cell surface receptors. PMID:25505603

  19. Cytochrome P1B1 (CYP1B1) polymorphisms and cancer risk: a meta-analysis of 52 studies.

    PubMed

    Li, Cuiping; Long, Bingshuang; Qin, Xianjing; Li, Weixiong; Zhou, Yang

    2015-01-02

    CYP1B1 plays a critical role in the oxidative metabolism of a variety of exogenous compounds, including carcinogenic compounds, which may be activated during metabolism. There are only a few studies that have examined the association between the two polymorphisms and cancer, and that these studies have been inconclusive. Hence, the aim of the present meta-analysis was to evaluate the relationship between polymorphisms in CYP1B1 G119T and A453G and cancer risk. We performed a detailed search using the PubMed and EMBASE libraries to obtain all relevant published reports on the relationship between the G119T and A453G polymorphisms in CYP1B1 and cancer risk. Combined odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated by Stata version 11.2. We conducted stratified analyses based on cancer types, ethnicity, source of controls, and quality assessments. We also made assessments of heterogeneity tests, sensitivity analyses, and publication bias. There were a total of 25 articles with 15,376 cases and 18,382 controls concerning CYP1B1 G119T and 40 articles with 27,983 cases and 35,839 controls concerning A453G polymorphisms. Regarding G119T, the combined results indicate that the variant genotypes were significantly associated with a slightly increased cancer risk in comparison to the homozygote (TT versus GG: p=0.006, OR=1.231, 95% CI: 1.061-1.428), especially for breast cancer and prostate cancer. Moreover, significantly increased associations with cancer risk were demonstrated in Asians in all genetic models. The combined results indicated no association of A453G with cancer risk; however, an association was observed specifically for prostate cancer. This meta-analysis suggests that the CYP1B1 G119T polymorphism may confer to genetic susceptibility to cancer in Asians, especially to breast cancer and prostate cancer. The A453G polymorphism was found to modify the risk of prostate cancer.

  20. Cytochrome P1B1 (CYP1B1) polymorphisms and ovarian cancer risk: a meta-analysis.

    PubMed

    Gajjar, Ketan; Owens, Gemma; Sperrin, Matthew; Martin-Hirsch, Pierre L; Martin, Francis L

    2012-12-16

    CYP1B1 is a key P450 enzyme involved in the metabolism of exogenous and endogenous substrates and plays a key role in hormone-induced carcinogenesis. Risk factors for ovarian cancer are related to hormonal exposure and reproduction, and polymorphisms within genes involved in metabolism of oestrogen and certain xenobiotics may influence the risk of developing ovarian cancer. Current meta-analysis evaluated four CYP1B1 polymorphisms (Leu432Val, Arg48Gly, Ala119Ser and Asn453Ser) for their association with ovarian cancer risk. A search of the MEDLINE bibliographic database for the period up to April 2012 identified five relevant studies. With regards to Leu432Val polymorphism, all of the five studies were eligible (1199 cases and 2596 controls) for analysis, while for Arg48Gly (799 cases and 1169 controls), Ala119Ser (799 cases and 1172 controls) and Asn453Ser (361cases and 1577 controls) only two studies were eligible for analysis. Fixed-effect models were used to estimate pooled odds ratios (OR) with 95% confidence intervals (95% CI) and chi-square based Q-test was used to test for heterogeneity. The pooled OR (95% CI) for CYP1B1_Leu432Val polymorphism were 1.1 (0.84-1.31) for heterozygous subjects and 0.82 (0.57-1.17) for homozygous Val subjects. In a recessive model, homozygous carriers of Leu432Val showed a weak trend towards reduced risk as compared to 'wild type' and heterozygous carriers (OR 0.8, 95% CI; 0.66-0.99); however, this association was of limited significance. Regarding Arg48Gly, the pooled OR (95% CI) were 1.06 (0.89-1.27) for heterozygous and 0.98 (1.72-1.33) for homozygous Gly subjects. With respect to Ala119Ser and Asn453Ser, the pooled OR were 1.06 (0.87-1.29) and 1.24 (0.94-1.63) for heterozygous and 1.1 (0.8-1.52) and 1.09 (0.5-2.34) for homozygous respectively. In conclusion, this meta-analysis suggests that CYP1B1 polymorphisms are not associated with ovarian cancer risk. Studies evaluating CYP1B1_Leu432Val polymorphism are required to

  1. Stability of aflatoxin B-1 and ochratoxin A in brewing.

    PubMed

    Chu, F S; Chang, C C; Ashoor, S H; Prentice, N

    1975-03-01

    The stability of aflatoxin B-1 and ochratoxin A in brewing was investigated by adding the purified toxins to the raw materials at 1 and 10 mug/g levels during mashing in a conventional micro-brewing process. The results indicate that both toxins are stable to heat and are insensitive to cooker mash treatment. Both mycotoxins were partially removed in the mashing and brewing processes. About 14 to 18% and 27 to 28% of the added toxins were found in the final beers brewed from starting materials containing 1 and 10 mug, respectively, of either toxin per g. The possible route of transmission of mycotoxins into beer is discussed.

  2. Estrogen therapy may counterbalance eutrophic remodeling of coronary arteries and increase bradykinin relaxation in a rat model of menopausal hypertension

    PubMed Central

    Matrai, Mate; Hetthéssy, Judit R.; Nadasy, Gyorgy L.; Szekacs, Bela; Mericli, Metin; Acs, Nandor; Monos, Emil; Arbib, Nissim; Varbiro, Szabolcs

    2016-01-01

    Abstract Objective: Hypertension causes adverse remodeling and vasomotor alterations in coronaries. Hormones such as estrogen may help counterbalance some of these effects. The aim of this study was to analyze the effects of ovariectomy and estrogen therapy in a rat model of menopausal hypertension induced by angiotensin II (AII). Methods: We investigated diameter, tone, and mechanics of intramural coronaries taken from ovariectomized female rats (n = 11) that received chronic AII treatment to induce hypertension, and compared the results with those found in female rats that were also given estrogen therapy (n = 11). The “hypertensive control” group (n = 11) underwent an abdominal sham operation, and received AII. After 4 weeks of AII treatment, side branches of left anterior descendent coronary (approximately 200 μm in diameter) were isolated, cannulated with plastic microcannulas at both ends, and studied in vitro in a vessel chamber. The inner and outer diameter of the arteries were measured by microangiometry, and spontenuous tone, wall thickness, wall cross-sectional area, tangential stress, incremental distensibility, circumferential incremental elastic modulus, thromboxane agonist-induced tone, and bradykinin-induced dilation were calculated. Results: In hypertension, intramural small coronaries show inward eutrophic remodeling after ovariectomy comparing with hypertensive controls. Estrogen therapy had an opposite effect on vessel diameter. Hormone therapy led to an increase in spontaneous tone, allowing for greater dilatative capacity. Conclusions: Estrogen may therefore be considered to counterbalance some of the adverse changes seen in the wall of intramural coronaries in the early stages of chronic hypertension. PMID:27187011

  3. Vasoinhibins Prevent Bradykinin-Stimulated Endothelial Cell Proliferation by Inactivating eNOS via Reduction of both Intracellular Ca2+ Levels and eNOS Phosphorylation at Ser1179

    PubMed Central

    Thebault, Stéphanie; González, Carmen; García, Celina; Zamarripa, David Arredondo; Nava, Gabriel; Vaca, Luis; López-Casillas, Fernando; de la Escalera, Gonzalo Martínez; Clapp, Carmen

    2011-01-01

    Vasoinhibins, a family of antiangiogenic peptides derived from prolactin proteolysis, inhibit the vascular effects of several proangiogenic factors, including bradykinin (BK). Here, we report that vasoinhibins block the BK-induced proliferation of bovine umbilical vein endothelial cells. This effect is mediated by the inactivation of endothelial nitric oxide synthase (eNOS), as the NO donor DETA-NONOate reverted vasoinhibin action. It is an experimentally proven fact that the elevation of intracellular Ca2+ levels ([Ca2+]i) upon BK stimulation activates eNOS, and vasoinhibins blocked the BK-mediated activation of phospholipase C and the formation of inositol 1,4,5-triphosphate leading to a reduced release of Ca2+ from intracellular stores. The [Ca2+]i rise evoked by BK also involves the influx of extracellular Ca2+ via canonical transient receptor potential (TRPC) channels. Vasoinhibins likely interfere with TRPC-mediated Ca2+ entry since La3+, which is an enhancer of TRPC4 and TRPC5 channel activity, prevented vasoinhibins from blocking the stimulation by BK of endothelial cell NO production and proliferation, and vasoinhibins reduced the BK-induced increase of TRPC5 mRNA expression. Finally, vasoinhibins prevented the BK-induced phosphorylation of eNOS at Ser1179, a post-translational modification that facilitates Ca2+-calmodulin activation of eNOS. Together, our data show that vasoinhibins, by lowering NO production through the inhibition of both [Ca2+]i mobilization and eNOS phosphorylation, prevent the BK-induced stimulation of endothelial cell proliferation. Thus, vasoinhibins help to regulate BK effects on angiogenesis and vascular homeostasis.

  4. (HFR-B1 experiment reporting and capsule disassembly)

    SciTech Connect

    Myers, B.F.

    1991-02-22

    The traveler visited the Joint Research Centre (JRC), Petten, The Netherlands, the Forschungszentrum GmbH (KFA), Juelich, Germany; and the Zentralinstitut fuer Kernforschung (ZfK), Rossendorf, Germany, during the period January 28 through February 9. At JRC, the analysis of the experiment HFR-B1 was discussed; a new schedule for issuance of the final data report was established. Other discussions at JRC concerned the capabilities of Petten to conduct two reactor experiments being proposed under the US/FRG cooperative program and the initial results of a proof test of Germany fuel spheres. At KFA, the main emphasis was on the disassembly of capsules 2 and 3 of the HFR-B1 experiment and agreement on the examinations and tests to be conducted with the disassembled components. The disassembly of capsule 3 was observed. Extensive discussions were conducted on the work, both experimental and analytical, being conducted in the Institut fuer Sicherheitsforschung und Reaktor Technologie. A major portion of the experimental work is being conducted at ZfK and a visit to this laboratory, sponosored by the KFA, was made on February 6 and 7. Cooperation with the US on the experimental and analytical work in the safety area was strongly emphasized. 1 tab.

  5. Screening and Initial Binding Assessment of Fumonisin B1 Aptamers

    PubMed Central

    McKeague, Maureen; Bradley, Charlotte R.; De Girolamo, Annalisa; Visconti, Angelo; Miller, J. David; DeRosa, Maria C.

    2010-01-01

    Fumonisins are mycotoxins produced by Fusarium verticillioides and F. proliferatum, fungi that are ubiquitous in corn (maize). Insect damage and some other environmental conditions result in the accumulation of fumonisins in corn-based products worldwide. Current methods of fumonisin detection rely on the use of immunoaffinity columns and high-performance liquid chromatography (HPLC). The use of aptamers offers a good alternative to the use of antibodies in fumonisin cleanup and detection due to lower costs and improved stability. Aptamers are single-stranded oligonucleotides that are selected using Systematic Evolution of Ligands by EXponential enrichment (SELEX) for their ability to bind to targets with high affinity and specificity. Sequences obtained after 18 rounds of SELEX were screened for their ability to bind to fumonisin B1. Six unique sequences were obtained, each showing improved binding to fumonisin B1 compared to controls. Sequence FB1 39 binds to fumonisin with a dissociation constant of 100 ± 30 nM and shows potential for use in fumonisin biosensors and solid phase extraction columns. PMID:21614178

  6. Enhancement of neural and thermal vasoconstriction by prostaglandin B1.

    PubMed

    Engelbrecht, J A; Greenberg, S; Wilson, W R

    1975-03-01

    The vascular effects of prostaglandin B1 (PGB1) were studied during constant-flow perfusion of the canine hindpaw. The effects of PGB1 (50-200 ng/kg/min ia) on systemic and hindpaw perfusion pressures and on responses to local cooling (4 degrees C for 90 sec) and local heating (45 degrees C for 60 sec) were measured in 15 dogs. PGB1 (50-100 ng/kg/min) decreased perfusion pressure without any significant effect on systemic arterial pressure. Higher concentrations of PGB1 (200 ng/kg/min) elevated perfusion pressure to control values. The pressor responses to local cooling were increased from 11 to 32 mmHg while the dilator responses to local heating and nitroglycerin were reduced during infusions of PGB1. PGB1 also enhanced the pressor responses to norepinephrine or tyramine. These findings support the conclusions that (1) low concentrations of prostaglandin B1 enhance neurotransmitter release with minimal effects on vascular smooth muscle cells and (2) these effects are not secondary to increased perfusion pressures or vascular wall stresses since infusions of PGB1 resulted in vasodilation.

  7. Hepatitis in Mice Infected with Coxsackie Virus B1*

    PubMed Central

    Burch, G. E.; Tsui, C. Y.; Harb, J. M.

    1973-01-01

    The livers of mice of different ages were readily damaged by Coxsackie virus B1 infection. The severity of liver damage decreased as the age of the mice increased. Coxsackie B1<