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1.
Article in English | MEDLINE | ID: mdl-36126860

ABSTRACT

6-Nitrodopamine (6-ND) is a novel catecholamine that is released from human umbilical cord vessels and Chelonoidis carbonaria aortic rings. The synthesis/release of 6-ND is inhibited by either pre-incubation of the vessels with the nitric oxide (NO) synthase inhibitor L-NAME or by mechanical removal of the endothelium. 6-ND causes powerful vasorelaxation, acting as a potent and selective dopamine D2-like receptor antagonist. Basal release of 6-ND from Panterophis guttatus endothelium intact and denuded aortic rings was quantified by LC-MS/MS. In order to evaluate the interaction of 6-ND with other catecholamines, aortic rings were suspended vertically between two metal hooks in 10-mL organ baths containing Krebs-Henseleit's solution and attached to isometric transducers. Endothelium intact aortic rings presented basal release of 6-ND, which was significantly reduced by previous incubation with L-NAME (100 µM). In endothelin-1 (3 nM) pre-contracted endothelium intact aortic rings, 6-ND (10pM-1 µM) and the dopamine D2-receptor antagonist L-761,626 (10 pM-1 µM) induced concentration-dependent relaxations, which were not affected by incubation with L-NAME but greatly reduced in endothelium-removed aortic rings. 6-ND (0.1-1 µM) produced significant rightward shifts of the concentration-response curves to dopamine in L-NAME pre-treated endothelium-intact (pA2 7.01) rings. Contractions induced by noradrenaline and adrenaline were not affected by pre-incubation with 6-ND (1 µM). The EFS-induced contractions of L-NAME pre-treated endothelium-intact aortic rings were significantly inhibited by incubation with 6-ND (1 µM). The results indicate that 6-ND released from Pantherophis guttatus aortic rings is coupled to NO release and represents a new mechanism by which NO can modulate vascular reactivity independently of cGMP production.


Subject(s)
Dopamine , Nitric Oxide , Aorta, Thoracic , Chromatography, Liquid , Dopamine/analogs & derivatives , Endothelin-1/pharmacology , Epinephrine , Humans , NG-Nitroarginine Methyl Ester/pharmacology , Norepinephrine/pharmacology , Tandem Mass Spectrometry
2.
Biol Open ; 10(1)2021 01 20.
Article in English | MEDLINE | ID: mdl-33277238

ABSTRACT

The contractions of Chelonoidis carbonaria aortic rings induced by electrical field stimulation (EFS) are not inhibited by blockade of the voltage-gated sodium channels by tetrodotoxin but almost abolished by the α1/α2-adrenoceptor antagonist phentolamine. The objective of this study was to identify the mediator(s) responsible for the EFS-induced contractions of Chelonoidis carbonaria aortic rings. Each ring was suspended between two wire hooks and mounted in isolated 10 ml organ chambers filled with oxygenated and heated Krebs-Henseleit's solution. Dopamine, noradrenaline and adrenaline concentrations were analysed by liquid chromatography coupled to tandem mass spectrometry. The contractions caused by dopamine and EFS were done in absence and presence of the nitric oxide (NO) synthesis inhibitor L-NAME, the NO-sensitive guanylyl cyclase inhibitor ODQ, the D1-like receptor antagonist SCH-23390, the D2-like receptor antagonists risperidone, quetiapine, haloperidol, and the tyrosine hydroxylase inhibitors salsolinol and 3-iodo-L-tyrosine. Basal concentrations of dopamine, noradrenaline and adrenaline were detected in Krebs-Henseleit solution containing the aortic rings. The catecholamine concentrations were significantly reduced in endothelium-denuded aortic rings. L-NAME and ODQ significantly potentiated the dopamine-induced contractions. The D2-like receptor antagonists inhibited the EFS-induced contractions of the aortic rings treated with L-NAME, whereas SCH 23390 had no effect. Similar results were observed in the contractions induced by dopamine in L-NAME treated aortic rings. These results indicate that catecholamines released by endothelium regulate the EFS-induced contractions. This may constitute a suitable mechanism by which reptilia modulate specific organ blood flow distribution.This paper has an associated First Person interview with the first author of the article.


Subject(s)
Aorta/physiology , Catecholamines/biosynthesis , Electric Stimulation , Endothelium, Vascular/metabolism , Muscle Contraction , Animals , Chromatography, Liquid , Dopamine/metabolism , Immunohistochemistry , Receptors, Dopamine/metabolism , Tandem Mass Spectrometry , Turtles
3.
Eur J Pharmacol ; 890: 173636, 2021 Jan 05.
Article in English | MEDLINE | ID: mdl-33053380

ABSTRACT

Inflammatory arthritis, such as rheumatoid arthritis (RA), stands out as one of the main sources of pain and impairment to the quality of life. The use of hemopressin (PVNFKFLSH; Hp), an inverse agonist of type 1 cannabinoid receptor, has proven to be effective in producing analgesia in pain models, but its effect on neuro-inflammatory aspects of RA is limited. In this study, antigen-induced arthritis (AIA) was evoked by the intraarticular (i.art.) injection of methylated bovine serum albumin (mBSA) in male Sprague Dawley rats. Phosphate buffered saline (PBS)-injected ipsilateral knee joints or AIA contralateral were used as control. Nociceptive and inflammatory parameters such as knee joint oedema and leukocyte influx and histopathological changes were carried out in addition to the local measurement of interleukins (IL) IL-6, IL-1ß, tumor necrosis factor-α and the immunoreactivity of the neuropeptides substance P (SP) and calcitonin gene related peptide (CGRP) in the spinal cord (lumbar L3-5 segments) of AIA rats. For 4 days, AIA rats were treated daily with a single administration of saline, Hp injected (10 or 20 µg/day, i.art.), Hp given orally (20 µg/Kg, p.o.) or indomethacin (Indo; 5 mg/Kg, i.p.). In comparison to the PBS control group, the induction of AIA produced a significant and progressive mono-arthritis condition. The degree of AIA severity progressively compromised the normal walking pattern and impaired mobility over the next four days in relation to PBS-injected rats or contralateral knee joints. In AIA rats, the reduction of the distance between footprints and disturbances of gait evidenced signs of nociception. This response worsened at day 4, and a loss of footprint from the ipsilateral hind paw was evident. Daily treatment of the animals with Hp either i.art. (10 and 20 µg/knee) or p.o. (20 µg/Kg) as well as Indo (5 mg/Kg, i.p.) ameliorated the impaired mobility in a time-dependent manner (P < 0.05). In parallel, the AIA-injected ipsilateral knee joints reach a peak of swelling 24 h after AIA induction, which persisted over the next four days in relation to PBS-injected rats or contralateral knee joints. There was a significant but not dose-dependent inhibitory effect produced by all dosages and routes of Hp treatments on AIA-induced knee joint swelling (P < 0.05). In addition, the increased synovial levels of MPO activity, total leukocytes number and IL-6, but not IL-1ß, were significantly reduced by the lower i.art. dose of Hp. In conclusion, these results successfully demonstrate that Hp may represent a novel therapeutic strategy to treat RA, an effect which is unrelated to the proinflammatory actions of the neuropeptides CGRP and SP.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Arthritis, Experimental/drug therapy , Arthritis, Rheumatoid/drug therapy , Hemoglobins/pharmacology , Nociceptive Pain/prevention & control , Peptide Fragments/pharmacology , Administration, Oral , Animals , Anti-Inflammatory Agents/administration & dosage , Behavior, Animal/drug effects , Cytokines/metabolism , Edema/drug therapy , Gait/drug effects , Hemoglobins/administration & dosage , Inflammation/drug therapy , Injections, Intra-Articular , Knee Joint/drug effects , Knee Joint/metabolism , Knee Joint/pathology , Leukocytes/drug effects , Male , Peptide Fragments/administration & dosage , Rats, Sprague-Dawley , Receptors, Calcitonin Gene-Related Peptide/metabolism , Substance P/metabolism
4.
Pharmacol Res Perspect ; 8(4): e00612, 2020 08.
Article in English | MEDLINE | ID: mdl-32567793

ABSTRACT

Electrical field stimulation (EFS) induces contractions of both snake aorta and human umbilical cord vessels (HUCV) which were dependent on the presence of the endothelium. This study aimed to establish the nature of the mediator(s) responsible for EFS-induced contractions in HUCV. Rings with or without endothelium from human umbilical artery (HUA) or vein (HUV) were mounted in organ bath chambers containing oxygenated, heated Krebs-Henseleit's solution. Basal release of dopamine (DA), noradrenaline, and adrenaline was measured by LC-MS-MS. Cumulative concentration-response curves were performed with dopamine in the absence and in the presence of L-NAME or of dopamine antagonists. EFS studies were performed in the presence and absence of L-NAME, the α-adrenergic blockers prazosin and idazoxan, and the dopamine antagonists SCH-23390 and haloperidol. Tyrosine hydroxylase (TH) and dopa-decarboxylase (DDC) were studied by immunohistochemistry and fluorescence in situ hybridizations. Basal release of dopamine requires an intact endothelium in both HUA and HUV. TH and DDC are present only in the endothelium of both HUA and HUV as determined by immunohistochemistry. Dopamine induced contractions in HUA only in the presence of L-NAME. Dopamine-induced contractions in HUV were strongly potentiated by L-NAME. The EFS-induced contractions in both HUA and HUV were potentiated by L-NAME and inhibited by the D2-like receptor antagonist haloperidol. The α-adrenergic antagonists prazosin and idazoxan and the D1-like receptor antagonist SCH-23390 had no effect on the EFS-induced contractions of HUA and HUV. Endothelium-derived dopamine is a major modulator of HUCV reactivity in vitro.


Subject(s)
Dopamine/metabolism , Electric Stimulation , Umbilical Arteries/metabolism , Umbilical Veins/metabolism , Adolescent , Adrenergic alpha-Antagonists/pharmacology , Adult , Chromatography, Liquid , Dopamine Antagonists/pharmacology , Endothelium, Vascular/physiology , Epinephrine/metabolism , Female , Humans , Middle Aged , Norepinephrine/metabolism , Tandem Mass Spectrometry , Young Adult
5.
Eur J Pharmacol, v. 890, 173636, jan. 2020
Article in English | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3856

ABSTRACT

Inflammatory arthritis, such as rheumatoid arthritis (RA), stands out as one of the main sources of pain and impairment to the quality of life. The use of hemopressin (PVNFKFLSH; Hp), an inverse agonist of type 1 cannabinoid receptor, has proven to be effective in producing analgesia in pain models, but its effect on neuro-inflammatory aspects of RA is limited. In this study, antigen-induced arthritis (AIA) was evoked by the intraarticular (i.art.) injection of methylated bovine serum albumin (mBSA) in male Sprague Dawley rats. Phosphate buffered saline (PBS)-injected ipsilateral knee joints or AIA contralateral were used as control. Nociceptive and inflammatory parameters such as knee joint oedema and leukocyte influx and histopathological changes were carried out in addition to the local measurement of interleukins (IL) IL-6, IL-1β, tumor necrosis factor-α and the immunoreactivity of the neuropeptides substance P (SP) and calcitonin gene related peptide (CGRP) in the spinal cord (lumbar L3-5 segments) of AIA rats. For 4 days, AIA rats were treated daily with a single administration of saline, Hp injected (10 or 20 μg/day, i.art.), Hp given orally (20 μg/Kg, p.o.) or indomethacin (Indo; 5 mg/Kg, i.p.). In comparison to the PBS control group, the induction of AIA produced a significant and progressive mono-arthritis condition. The degree of AIA severity progressively compromised the normal walking pattern and impaired mobility over the next four days in relation to PBS-injected rats or contralateral knee joints. In AIA rats, the reduction of the distance between footprints and disturbances of gait evidenced signs of nociception. This response worsened at day 4, and a loss of footprint from the ipsilateral hind paw was evident. Daily treatment of the animals with Hp either i.art. (10 and 20 μg/knee) or p.o. (20 μg/Kg) as well as Indo (5 mg/Kg, i.p.) ameliorated the impaired mobility in a time-dependent manner (P < 0.05). In parallel, the AIA-injected ipsilateral knee joints reach a peak of swelling 24 h after AIA induction, which persisted over the next four days in relation to PBS-injected rats or contralateral knee joints. There was a significant but not dose-dependent inhibitory effect produced by all dosages and routes of Hp treatments on AIA-induced knee joint swelling (P < 0.05). In addition, the increased synovial levels of MPO activity, total leukocytes number and IL-6, but not IL-1β, were significantly reduced by the lower i.art. dose of Hp. In conclusion, these results successfully demonstrate that Hp may represent a novel therapeutic strategy to treat RA, an effect which is unrelated to the proinflammatory actions of the neuropeptides CGRP and SP

6.
Appl Immunohistochem Mol Morphol ; 26(10): 760-768, 2018.
Article in English | MEDLINE | ID: mdl-28719381

ABSTRACT

INTRODUCTION: Experimental evidences from the last 2 decades supports the existence of a special type of neoplastic cell with stem-like features [cancer stem cell (CSC)] and their role in the pathophysiology and therapeutic resistance of breast cancer. However, their clinical value in human breast cancer has not been fully determined. MATERIALS AND METHODS: An immunohistochemistry panel of 10 putative CSC markers (CD34, C-KIT, CD10, SOX-2, OCT 3/4, p63, CD24, CD44, CD133, and ESA/EPCAM) was applied to 74 cases of breast cancer, followed in a Regional Cancer Center of Minas Gerais State, Brazil, from 2004 to 2006. Possible associations between CSC markers and classic variables of clinicopathologic relevance were investigated. RESULTS: The most frequently positive CSC markers were CD44, CD24, CD133, and ESA (the others were present in <15% of the cases). Two CSC profiles were defined: CD24/CD44 (CSC-1) and CD133/ESA (CSC-2). CSC-1 was significantly associated to patients older than 40 years, tumors of <2.0 cm in diameter, early clinical stages (P<0.05), and increased death risk of 4 times (P=0.03; 95% confidence interval, 1.09-14.41). CSC-2 was related to increased relapse risk of 3.75 times (P=0.04; 95% confidence interval, 1.02-13.69). CONCLUSION: The detection of the most frequently positive CSC markers by immunohistochemistry is of clinicopathologic and prognostic relevance.


Subject(s)
Biomarkers, Tumor/metabolism , Carcinoma, Ductal, Breast , Neoplasm Proteins/metabolism , Adult , Age Factors , Aged , Aged, 80 and over , Brazil , Breast Neoplasms/metabolism , Breast Neoplasms/mortality , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/metabolism , Carcinoma, Ductal, Breast/mortality , Carcinoma, Ductal, Breast/pathology , Disease-Free Survival , Female , Humans , Immunohistochemistry , Middle Aged , Neoplasm Invasiveness , Risk Factors , Survival Rate
8.
Breast Cancer (Auckl) ; 9(Suppl 2): 45-55, 2015.
Article in English | MEDLINE | ID: mdl-26609237

ABSTRACT

The present review is focused on the current role of neoplastic stem and progenitor-like cells as primary targets in the pharmacotherapy of cancer as well as in the development of new anticancer drugs. We begin by summarizing the main characteristics of these tumor-initiating cells and key concepts that support their participation in therapeutic failure. In particular, we discuss the differences between the major carcinogenesis models (ie, clonal evolution vs cancer stem cell (CSC) model) with emphasis on breast cancer (given its importance to the study of CSCs) and their implications for the development of new treatment strategies. In addition, we describe the main ways to target these cells, including the main signaling pathways that are more activated or altered in CSCs. Finally, we provide a comprehensive compilation of the most recently tested drugs.

9.
Am J Physiol Lung Cell Mol Physiol ; 304(10): L639-45, 2013 May 15.
Article in English | MEDLINE | ID: mdl-23475769

ABSTRACT

Bone marrow (BM) eosinopoiesis is a common feature during allergen exposure in atopic individuals. Airway exposure to staphylococcal superantigens aggravates allergic airway disease and increases the output of BM eosinophils. However, the exact mechanisms regulating eosinophil mobilization and trafficking to the peripheral circulation and airways remain to be elucidated. Therefore, this study aimed to investigate the mechanisms determining the BM eosinopoiesis in allergic mice under exposure to staphylococcal enterotoxin A (SEA). Ovalbumin (OVA)-sensitized male BALB/C mice were intranasally exposed to SEA (1 µg), and at 4, 12, 24, and 48 h later animals were challenged with OVA (10 µg, twice a day). Measurement of IL-5, eotaxin, and granulocyte-macrophage colony-stimulating factor (GM-CSF) levels, flow cytometry for CCR3(+), VLA4(+), and CCR3(+)VLA4(+), as well as adhesion assays to VCAM-1 were performed in BM. Prior airway exposure to SEA time dependently increased the BM eosinophil number in OVA-challenged mice. Eosinophils gradually disappear from peripheral blood, being recruited over time to the airways, where they achieve a maximal infiltration at 24 h. SEA exposure increased the levels of IL-5 and eotaxin (but not GM-CSF) in BM of OVA-challenged mice. Marked increases in CCR3(+) and CCR3(+)VLA4(+) expressions in BM eosinophils of OVA-challenged mice were observed, an effect largely reduced by prior exposure to SEA. Adhesion of BM eosinophils to VCAM-1 was increased in OVA-challenged mice, but prior SEA exposure abrogated this enhanced cell adhesion. Accumulation of BM eosinophils by airway SEA exposure takes place through IL-5- and CCR3-dependent mechanisms, along with downregulation of CCR3/VL4 and impaired cell adhesion to VCAM-1.


Subject(s)
Allergens/immunology , Bone Marrow/immunology , Cell Movement/immunology , Enterotoxins/immunology , Eosinophilia/immunology , Respiratory System/immunology , Allergens/metabolism , Animals , Bone Marrow/metabolism , Bone Marrow/pathology , Eosinophilia/metabolism , Eosinophilia/pathology , Eosinophils/immunology , Eosinophils/metabolism , Eosinophils/pathology , Granulocyte-Macrophage Colony-Stimulating Factor/immunology , Granulocyte-Macrophage Colony-Stimulating Factor/metabolism , Integrin alpha4beta1/immunology , Integrin alpha4beta1/metabolism , Interleukin-5/immunology , Interleukin-5/metabolism , Male , Mice , Mice, Inbred BALB C , Ovalbumin/immunology , Receptors, CCR3/immunology , Receptors, CCR3/metabolism , Respiratory System/metabolism , Respiratory System/pathology , Vascular Cell Adhesion Molecule-1/immunology , Vascular Cell Adhesion Molecule-1/metabolism
10.
Article in English | MEDLINE | ID: mdl-22134054

ABSTRACT

We characterized the nitric oxide (NO)-cyclic GMP-phosphodiesterase-5 (PDE5) pathway in Crotalus durissus terrificus aorta. Concentration responses curves to acetylcholine (ACh), sodium nitroprusside (SNP), BAY41-2272 (soluble guanylyl cyclase [sGC] stimulator), BAY60-2770 (sGC activator) and tadalafil (PDE5 inhibitor) were constructed in phenylephrine (10 µM)-precontracted tissues with intact (E(+)) or denuded (E(-)) endothelium. ACh (0.0001-10 µM) and SNP (0.0001-10 µM) relaxed aorta, which were reduced by the NO synthase (L-NAME,100 µM) or the sGC inhibitors (ODQ, 10 µM). Tadalafil (0.0001-10 µM) relaxed E(+) rings with potency (pEC(50)) and maximal response (E(max)) values of 7.34±0.02 and 105±8%, respectively. E(-) or ODQ treatment significantly (P<0.05) reduced tadalafil relaxations (66±18% and 71±7%, respectively). BAY41-2272 (0.0001-300 nM) produced concentration-dependent relaxations in E(+) rings, which were reduced by addition of either ODQ or L-NAME (16.0- and 5.2-fold rightward shifts, respectively). The relaxation of BAY60-2770 was markedly potentiated by ODQ and L-NAME (41.0- and 9.7-fold leftward shifts, respectively), whereas in E(-) the pEC(50) values were shifted by 7-fold to the right. Immunohistochemistry, followed validation by transcriptomic analysis, revealed the presence of eNOS in endothelium, whereas nNOS was observed only in perivascular nerves. sGC and PDE5 were expressed in smooth muscle. Thus, NO-sGC-PDE5 pathway is evolutionarily present in Crotalus sp. vessels, and has a remarkable degree of functional similarity to mammalian vessels.


Subject(s)
Aorta/physiology , Crotalus/physiology , Cyclic Nucleotide Phosphodiesterases, Type 5/metabolism , Nitric Oxide/metabolism , Signal Transduction , Acetylcholine/pharmacology , Animals , Aorta/cytology , Aorta/drug effects , Aorta/metabolism , Carbolines/pharmacology , Crotalus/genetics , Crotalus/metabolism , Endothelium, Vascular/cytology , Endothelium, Vascular/metabolism , Endothelium, Vascular/physiology , Gene Expression Profiling , Guanylate Cyclase/antagonists & inhibitors , Guanylate Cyclase/metabolism , Immunohistochemistry/methods , In Vitro Techniques , Male , Muscle, Smooth, Vascular/metabolism , Muscle, Smooth, Vascular/physiology , NG-Nitroarginine Methyl Ester/pharmacology , Nitric Oxide Synthase Type III/genetics , Nitric Oxide Synthase Type III/metabolism , Nitroprusside/pharmacology , Phenylephrine/pharmacology , Pyrazoles/pharmacology , Pyridines/pharmacology , Receptors, Cytoplasmic and Nuclear/antagonists & inhibitors , Receptors, Cytoplasmic and Nuclear/metabolism , Soluble Guanylyl Cyclase , Tadalafil , Vasodilation
11.
Neurourol Urodyn ; 30(7): 1392-402, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21661033

ABSTRACT

AIMS: Association between arterial hypertension and urinary bladder dysfunction has been reported in humans and spontaneously hypertensive rats. However, no study exists evaluating the bladder dysfunction in conditions of renovascular hypertension. The purpose of this study was to characterize the bladder dysfunction in two kidney-one clip (2K-1C) hypertensive rats. METHODS: A silver clip was placed around the renal artery of male Wistar rats. After 8 weeks, cystometric study, concentration-response curves to contractile and relaxant agents, frequency-dependent contractions, histomorphometry, muscarinic M(2) /M(3) mRNA expression and cyclic AMP measurements were performed. RESULTS: 2K-1C rats showed enhanced bladder volume, wall thickness and smooth muscle density. 2K-1C rats also exhibited increases in bladder capacity and non-void contractions, and decreases in the inter-contraction intervals. In isolated detrusor smooth muscle (DSM), contractions to carbachol and electrical-field stimulation (EFS) were significantly greater in 2K-1C rats. The Rho-kinase inhibitor Y27632 (10 µM) significantly reduced the carbachol-induced contractions in SHAM and 2K-1C rats, but DSM remained overactive in 2K-1C rats in presence of Y27632. Concentration-dependent contractions to the P2X receptor agonist α,ß-methylene ATP, KCl and extracellular Ca(2+) did not change between SHAM and 2K-1C groups. In 2K-1C rats, isoproterenol, metaproterenol and BRL 37-344 (non-selective, ß(2) - and ß(3) -selective adrenoceptor agonists, respectively) produced significantly lower relaxations and decreased cAMP levels, whereas relaxant responses to sodium nitroprusside and BAY 41-2272 remained unchanged. Muscarinic M(3) mRNA expression receptors were higher in 2K-1C group. CONCLUSIONS: Renovascular hypertensive rats exhibit bladder dysfunction that involves tissue remodeling and enhanced muscarinic M(3) -mediated contractions associated with reduced ß-adrenoceptor-mediated signal transduction.


Subject(s)
Hypertension, Renovascular/complications , Muscle Contraction , Muscle Relaxation , Muscle, Smooth/physiopathology , Urinary Bladder Diseases/etiology , Urinary Bladder/physiopathology , Adrenergic beta-Agonists/pharmacology , Animals , Cholinergic Agonists/pharmacology , Cyclic AMP/metabolism , Disease Models, Animal , Dose-Response Relationship, Drug , Electric Stimulation , Hypertension, Renovascular/physiopathology , Male , Muscle Contraction/drug effects , Muscle Relaxation/drug effects , Muscle, Smooth/drug effects , Muscle, Smooth/innervation , Muscle, Smooth/metabolism , Muscle, Smooth/pathology , Neuromuscular Agents/pharmacology , Protein Kinase Inhibitors/pharmacology , Purinergic P2X Receptor Agonists/pharmacology , RNA, Messenger/metabolism , Rats , Rats, Wistar , Receptor, Muscarinic M3/genetics , Signal Transduction , Time Factors , Up-Regulation , Urinary Bladder/drug effects , Urinary Bladder/innervation , Urinary Bladder/metabolism , Urinary Bladder/pathology , Urinary Bladder Diseases/metabolism , Urinary Bladder Diseases/pathology , Urinary Bladder Diseases/physiopathology , Urodynamics , rho-Associated Kinases/antagonists & inhibitors
12.
J Sex Med ; 8(6): 1616-25, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21477017

ABSTRACT

INTRODUCTION: Coitus in snakes may last up to 28 hours; however, the mechanisms involved are unknown. AIM: To evaluate the relevance of the nitric oxide (NO)-cyclic guanosine monophosphate (cGMP)-phosphodiesterase type 5 (PDE5) system in snake corpus cavernosum reactivity. METHODS: Hemipenes were removed from anesthetized South American rattlesnakes (Crotalus durissus terrificus) and studied by light and scanning electronic microscopy. Isolated Crotalus corpora cavernosa (CCC) were dissected from the non-spiny region of the hemipenises, and tissue reactivity was assessed in organ baths. MAIN OUTCOME MEASURES: Cumulative concentration-response curves were constructed for acetylcholine (ACh), sodium nitroprusside (SNP), 5-cyclopropyl-2-[1-(2-fluorobenzyl)-1H-pyrazolo[3,4-b]pyridine-3-yl]pyrimidin-4-ylamine (BAY 41-2272), and tadalafil in CCC precontracted with phenylephrine. Relaxation induced by electrical field stimulation (EFS) was also done in the absence and presence of N(ω) nitro-L-arginine methyl ester (L-NAME; 100 µM), 1H-[1, 2, 4] oxadiazolo[4,3-a]quinoxalin-1-one (ODQ; 10 µM) and tetrodotoxin (TTX; 1 µM). RESULTS: The hemipenes consisted of two functionally concentric corpora cavernosa, one of them containing radiating bundles of smooth muscle fibers (confirmed by α-actin immunostaining). Endothelial and neural nitric oxide synthases were present in the endothelium and neural structures, respectively; whereas soluble guanylate cyclase and PDE5 were expressed in trabecular smooth muscle. ACh and SNP relaxed isolated CCC, with the relaxations being markedly reduced by L-NAME and ODQ, respectively. BAY 41-2272 and tadalafil caused sustained relaxations with potency (pEC(50) ) values of 5.84 ± 0.17 and 5.10 ± 0.08 (N=3-4), respectively. In precontracted CCC, EFS caused frequency-dependent relaxations that lasted three times longer than those in mammalian CC. Although these relaxations were almost abolished by either L-NAME or ODQ, they were unaffected by TTX. In contrast, EFS-induced relaxations in marmoset CC were abolished by TTX. CONCLUSIONS: Rattlesnake CC relaxation is mediated by the NO-cGMP-PDE5 pathway in a manner similar to mammals. The novel TTX-resistant Na channel identified here may be responsible for the slow response of smooth muscle following nerve stimulation and could explain the extraordinary duration of snake coitus.


Subject(s)
Cyclic GMP/metabolism , Nitrergic Neurons/drug effects , Nitric Oxide Synthase/metabolism , Penis/blood supply , Penis/innervation , Sodium Channel Blockers/pharmacology , Sodium Channels/drug effects , Sodium Channels/physiology , Tetrodotoxin/pharmacology , Acetylcholine/pharmacology , Animals , Callithrix , Carbolines/pharmacology , Crotalus , Cyclic Nucleotide Phosphodiesterases, Type 5/metabolism , Dose-Response Relationship, Drug , Endothelium, Vascular/anatomy & histology , Endothelium, Vascular/drug effects , In Vitro Techniques , Male , Microscopy, Electron, Scanning , NG-Nitroarginine Methyl Ester/pharmacology , Nitroprusside/pharmacology , Oxadiazoles/pharmacology , Penis/anatomy & histology , Pyrazoles/pharmacology , Pyridines/pharmacology , Quinoxalines/pharmacology , Tadalafil , Vasodilator Agents/pharmacology
13.
Int Immunopharmacol ; 11(6): 740-7, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21315171

ABSTRACT

DMTI-II (23-kDa trypsin inhibitor purified from Dimorphandra mollis seeds) promotes acute inflammation accompanied by an early infiltration of eosinophils, a critical cell type involved in allergic diseases. We have evaluated here the capacity of DMTI-II to enhance the allergic pulmonary inflammation, looking over time to the leukocyte trafficking from bone marrow to peripheral blood, and their recruitment into the allergic airways. Male Wistar rats were sensitized and challenged with ovalbumin (OVA). At 2 to 16h prior to OVA challenge, animals were exposed to DMTI-II (10µg). Bronchoalveolar lavage fluid (BAL), circulating blood and bone marrow were examined at 24h post-OVA challenge. Challenge with OVA significantly increased the influx of total inflammatory cells, neutrophils and eosinophils in BAL and lung tissue. Pre-exposure to DMTI-II potentiated total inflammatory cell and neutrophil recruitment (p<0.05). Neutropoiesis and neutrophilia accompanied pulmonary cell influx. Pre-exposure to DMTI-II also significantly increased eosinophil recruitment to BAL, an effect starting at 4h, remaining markedly elevated at 16h (p<0.05). Eosinopoiesis and eosinophilia (seen within 2 to 4h) were also observed. Exposure to DMTI-II alone increased the IL-4 levels, and further increased the IL-4 levels in OVA-challenged rats. The levels of IgE, LTB(4) and eotaxin in OVA-challenged rats were greater compared with non-sensitized rats, but DMTI-II exposure failed to further enhance such levels. In summary, our study shows that DMTI-II itself presents granulocytopoietic activity, and enhances allergen-induced neutrophil and eosinophil mobilization from bone marrow to lung tissues that is accompanied by enhanced IL-4 production.


Subject(s)
Interleukin-4/metabolism , Lung/drug effects , Neutrophils/metabolism , Plant Proteins/administration & dosage , Pneumonia/drug therapy , Trypsin Inhibitors/administration & dosage , Animals , Bronchoalveolar Lavage , Cell Differentiation/drug effects , Cell Movement/drug effects , Cell Proliferation/drug effects , Eosinophils/pathology , Fabaceae , Humans , Immunoglobulin E/blood , Lung/immunology , Lung/metabolism , Lung/pathology , Male , Neutrophils/immunology , Neutrophils/pathology , Ovalbumin/administration & dosage , Plant Proteins/chemistry , Pneumonia/chemically induced , Pneumonia/metabolism , Pneumonia/pathology , Rats , Rats, Wistar , Seeds , Trypsin Inhibitors/chemistry
14.
BJU Int ; 107(10): 1628-34, 2011 May.
Article in English | MEDLINE | ID: mdl-20942830

ABSTRACT

OBJECTIVE: • Obesity induced by high-fat diet (HFD) is one of the most important risk factor for the development of erectile dysfunction (ED) in man. This study aimed to characterize the ED resulting from obesity associated with HFD in mice. MATERIALS AND METHODS: • C57BL/6 mice fed for 10 weeks with either HFD to induce obesity or a standard-chow diet (SD) were used. Corpus cavernosum was surgically dissected free, and strips were mounted in 10-mL organ baths containing Krebs solution. • Functional responses to endothelium-dependent and -independent agents, as well as to electrical-field stimulation were measured in the cavernosal tissue. Levels of cGMP in erectile tissue were detected by enzyme immunoassay assay. RESULTS: • The potency (pEC(50)) and maximal response (E(max)) to acetylcholine were significantly lower in the HFD group compared with the SD group. A marked decrease in the non-adrenergic non-cholinergic (nitrergic) cavernosal relaxations in the HFD group was also detected. There were no significant differences between the SD and HFD groups for the cavernosal relaxations in response to sodium nitroprusside. • The contractile responses elicited by the α(1) -adrenoceptor agonist phenylephrine were significantly greater in the HFD group compared with the SD group. • Similarly, the electrical-field stimulation (2-8 Hz)-induced adrenergic contractions were markedly greater in HFD mice. The pEC(50) for endothelin-1 was about 6.9-fold higher in the HFD compared with SD group. • The basal cGMP content was 47% lower in HFD strips compared with SD group. There were no morphological alterations in erectile tissue of HFD group compared with SD mice. CONCLUSION: • Obesity associated with HFD favours ED as result of impaired endothelial and nitrergic cavernosal relaxations along with increased contractile responses to adrenergic stimulation and endothelin-1 receptor activation.


Subject(s)
Dietary Fats/adverse effects , Impotence, Vasculogenic/etiology , Nitric Oxide/metabolism , Obesity/complications , Penile Erection/physiology , Penis/physiopathology , Animals , Cyclic GMP , Impotence, Vasculogenic/physiopathology , Male , Mice , Mice, Inbred C57BL , Obesity/etiology , Obesity/physiopathology , Receptor, Endothelin A/physiology
15.
Tumour Biol ; 31(5): 489-93, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20563767

ABSTRACT

It is well established that hypoxic microenvironment contributes to breast cancer progression by activation of transcriptional genes that promote angiogenesis. By promoting the antioxidant activity of glutathione, glutathione S-transferases (GSTs) are likely to facilitate the hypoxia-inducible factor-1α (HIF-1α) activity, therefore stimulating the angiogenesis. We investigated herein the influence of the GSTM1 and GSTT1 polymorphisms in the intratumoral angiogenesis of 87 patients with sporadic breast cancer. The intratumoral microvessel density (IMVD) of formalin-fixed paraffin-embedded tissues samples from all patients was determined by immunohistochemistry. The high IMVD was defined as a median microvessel counting higher than 18.7 after the analysis of histogram with all the results. The high IMVD was more common in patients with the GSTT1 wild genotype than in those with the GSTT1 null genotype (P = 0.04). Our results suggest, for the first time, that the GSTT1 polymorphism constitutes an inherited determinant of intratumoral angiogenesis in sporadic breast cancer.


Subject(s)
Breast Neoplasms/blood supply , Breast Neoplasms/genetics , Glutathione Transferase/genetics , Neovascularization, Pathologic/genetics , Polymorphism, Genetic , Breast Neoplasms/pathology , Female , Genetic Predisposition to Disease , Humans , Immunohistochemistry , Microvessels/enzymology , Middle Aged , Neoplasm Staging
16.
BMC Cancer ; 9: 109, 2009 Apr 08.
Article in English | MEDLINE | ID: mdl-19356249

ABSTRACT

BACKGROUND: Sentinel lymph node (SLN) biopsy is a widely used diagnostic procedure in the management of early breast cancer. When SLN is free of metastasis, complete axillary dissection may be skipped for staging in clinically N0 patients, allowing a more conservative procedure. Histological tumor features that could reliably predict SLN status have not yet been established. Since the degree of tumor lymphangiogenesis and vascularization may theoretically be related to the risk of lymph node metastasis, we sought to evaluate the relationship between lymph vessel invasion (LVI), lymphatic microvascular density (LVD), microvascular density (MVD) and VEGF-A expression, with SLN status and other known adverse clinical risk factors. METHODS: Protein expression of D2-40, CD34, and VEGF-A was assessed by immunohistochemistry on paraffin-embedded sections of primary breast cancer specimens from 92 patients submitted to SLN investigation. The presence of LVI, the highest number of micro vessels stained for D2-40 and CD34, and the protein expression of VEGF-A were compared to SLN status, clinicopathological features and risk groups. RESULTS: LVI was detected in higher ratios by immunostaining with D2-40 (p < 0.0001), what would have changed the risk category from low to intermediate in four cases (4.3%). There was no association between LVI and other angiogenic parameters determined by immunohistochemistry with SLN macrometastases, clinical features or risk categories. CONCLUSION: Assessment of LVI in breast carcinoma may be significantly increased by immunostaining with D2-40, but the clinical relevance of altering the risk category using this parameter may not be advocated according to our results, neither can the use of LVI and LVD as predictors of SLN macrometastasis in early breast cancer.


Subject(s)
Antibodies, Monoclonal/analysis , Breast Neoplasms/diagnosis , Lymphangiogenesis , Membrane Glycoproteins/analysis , Neovascularization, Pathologic/diagnosis , Adult , Aged , Antibodies, Monoclonal, Murine-Derived , Antigens, CD34/analysis , Biomarkers, Tumor/analysis , Biomarkers, Tumor/immunology , Breast Neoplasms/blood supply , Breast Neoplasms/metabolism , Female , Humans , Immunohistochemistry , Logistic Models , Lymphatic Metastasis , Membrane Glycoproteins/immunology , Middle Aged , Neovascularization, Pathologic/metabolism , Predictive Value of Tests , Risk Factors , Sentinel Lymph Node Biopsy , Vascular Endothelial Growth Factor A/analysis
17.
BMC Cancer ; 8: 291, 2008 Oct 08.
Article in English | MEDLINE | ID: mdl-18840301

ABSTRACT

BACKGROUND: In order to elucidate tumoral progression and drug resistance, cultured cell lines are valuable tools applied on tumor related assays provided they are well established and characterized. Our laboratory settled the NG97 cell line derived from a human astrocytoma grade III, which started to develop and express important phenotypical characteristics of an astrocytoma grade IV after injection in the flank of nude mice. Astrocytomas are extremely aggressive malignancies of the Central Nervous System (CNS) and account for 46% of all primary malignant brain tumors. Progression to worse prognosis occurs in 85% of the cases possibly due to changes in cell tumor microenvironment and through biological pathways that are still unclear. METHODS: This work focused on characterizing the NG97 cell line specifically after being recovered from the xenotransplant, who maintained their undifferentiated characteristics along the following 60th passages in vitro. These cells were subcultivated to evaluate the possible contribution of these undifferentiated characteristics to the malignant progression phenotype. These characteristics were the expression of molecules involved in the processes of migration, dedifferentiation and chromosomal instability. RESULTS: Results showed that NG97(ht) had an decrease in doubling time through sub cultivation, which was characterized by a converse modulation between the expression of glial fibrillary acidic protein (GFAP) and vimentin. In addition, beta1 integrins were present in intermediate levels while alpha5 integrins had a high expression profile as well as fibronectin and laminin. Cytogenetic analysis of NG97(ht) revealed several chromosomal abnormalities, 89% of the cells showed to be hyperdiploid and the modal number was assigned to be 63. Several acrocentric chromosomes were visualized and at least 30 figures were attributed to be murine. These findings suggest a possible fusion between the original NG97 cells with stromal murine cells in the xenotransplant. CONCLUSION: In this study the NG97(ht) cells were characterized to embryonic recovery patterns of intermediate filaments, adhesion molecules expression, chromosomal imbalances and murine chromosomes. In the latter case, these presumably chromosomes were originated as fusions between murine stroma cells and NG97 cell lineage in the xenotransplant. Our results emphasize important queries about astrocytomas tumor progression.


Subject(s)
Astrocytoma/pathology , Animals , Astrocytoma/genetics , Astrocytoma/metabolism , Cell Growth Processes/physiology , Cell Line, Tumor , Chromosome Aberrations , Flow Cytometry , Glial Fibrillary Acidic Protein/biosynthesis , Humans , Integrin beta1/biosynthesis , Mice , Mice, Nude , Neoplasm Transplantation , Transplantation, Heterologous , Vimentin/biosynthesis
18.
Diabetes ; 56(8): 1986-98, 2007 08.
Article in English | MEDLINE | ID: mdl-17519423

ABSTRACT

Obesity is associated with insulin resistance and a state of abnormal inflammatory response. The Toll-like receptor (TLR)4 has an important role in inflammation and immunity, and its expression has been reported in most tissues of the body, including the insulin-sensitive ones. Because it is activated by lipopolysaccharide and saturated fatty acids, which are inducers of insulin resistance, TLR4 may be a candidate for participation in the cross-talk between inflammatory and metabolic signals. Here, we show that C3H/HeJ mice, which have a loss-of-function mutation in TLR4, are protected against the development of diet-induced obesity. In addition, these mice demonstrate decreased adiposity, increased oxygen consumption, a decreased respiratory exchange ratio, improved insulin sensitivity, and enhanced insulin-signaling capacity in adipose tissue, muscle, and liver compared with control mice during high-fat feeding. Moreover, in these tissues, control mice fed a high-fat diet show an increase in IkappaB kinase complex and c-Jun NH(2)-terminal kinase activity, which is prevented in C3H/HeJ mice. In isolated muscles from C3H/HeJ mice, protection from saturated fatty acid-induced insulin resistance is observed. Thus, TLR4 appears to be an important mediator of obesity and insulin resistance and a potential target for the therapy of these highly prevalent medical conditions.


Subject(s)
Insulin Resistance , Obesity/metabolism , Obesity/prevention & control , Toll-Like Receptor 4/metabolism , Adipose Tissue/pathology , Adipose Tissue/ultrastructure , Animal Feed , Animals , Blood Glucose/metabolism , Body Weight , Cell Shape , Dietary Fats/pharmacology , Enzyme Activation , Fatty Acids/pharmacology , I-kappa B Kinase/metabolism , Insulin/metabolism , Insulin Receptor Substrate Proteins , Insulin Resistance/genetics , JNK Mitogen-Activated Protein Kinases/metabolism , Liver/drug effects , Liver/metabolism , Male , Mice , Microscopy, Electron, Transmission , Muscles/drug effects , Muscles/metabolism , Mutation/genetics , Obesity/genetics , Obesity/pathology , Phosphoproteins/metabolism , Phosphoserine/metabolism , Signal Transduction , Toll-Like Receptor 4/deficiency , Toll-Like Receptor 4/genetics , Triglycerides/metabolism
19.
Arq. neuropsiquiatr ; 63(4): 1084-1089, dez. 2005. ilus
Article in English | LILACS | ID: lil-419024

ABSTRACT

INTRODUÇÃO: Neurocitoma central é um tumor neuroectodérmico raro, geralmente localizado nos ventrículos laterais. RELATO DE CASOS: Uma mulher de 26 anos e um homem de 33 anos apresentaram-se com hipertensão intracraniana. Exames de imagem revelaram tumor intraventricular heterogêneo, que impregnava por contraste, ocupando os ventrículos laterais e causando hidrocefalia. A mulher faleceu no pós-operatório e o homem está livre de recidiva após três anos. HISTOPATOLOGIA: Ambos os tumores eram sólidos, com células arredondadas, lembrando oligodendroglia, positivas para sinaptofisina, cromogranina e NSE e algumas para GFAP, vimentina e proteína S-100. Microscopia eletrônica mostrou neurópilo entre os corpos celulares, mas sinapses eram raras.


Subject(s)
Adult , Female , Humans , Male , Cerebral Ventricle Neoplasms/diagnosis , Neurocytoma/diagnosis , Cerebral Ventricle Neoplasms/surgery , Cerebral Ventricle Neoplasms/ultrastructure , Immunohistochemistry , Microscopy, Electron , Neurocytoma/surgery , Neurocytoma/ultrastructure
20.
Cell Mol Neurobiol ; 25(5): 929-41, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16133944

ABSTRACT

1. A human glioma cell line, NG97, was established by Grippo et al. in 2001 from tissue obtained from a grade III astrocytoma (WHO, 2000). In this first study, the cell line grew as two morphologically distinct subpopulations: dendritic/spindle cells and small round cells. The injection of NG97 cells into nude mice induced an aggressive tumor characterized by: severe cytological atypia, vascular proliferation and pseudopalisading necrosis (glioblastoma multiforme features). 2. The purpose of the present study was to characterize the immunophenotype and ultrastructural aspects of this cell line, using the parental tumor, cultured cells and the xenotransplant, in order to assess its glial nature and possible divergent differentiation. 3. NG97 cells and xenotransplant expressed the main neuroglial markers (GFAP, S-100 protein, NSE and Leu-7) and showed no aberrant expression of other histogenetic markers. GFAP was similarly expressed in the parental tumor and in the cells in culture, but decreased in the xenotransplant. NSE expression was reduced in NG97 cells, but substantially recovered in the xenotransplant. This variability in expression of GFAP and NSE was interpreted as either a phenomenon of dedifferentiation or to microenvironmental selection of specific subclones. S-100 was equally expressed in the three contexts. The xenotransplant's ultrastructural features were those of a highly undifferentiated tumor. No significant immunophenotypic or ultrastructural differences between the two morphologically distinct populations were found. 4. Thus, our data demonstrate that NG97 cells constitute a pure glial-committed cell line, which may prove useful as a malignant glioma model in studies addressing pathophysiological, diagnostic and therapeutic issues.


Subject(s)
Brain Neoplasms/pathology , Cell Culture Techniques/standards , Cell Line, Tumor , Glioblastoma/pathology , Animals , Biomarkers , Cell Differentiation , Cell Line, Tumor/ultrastructure , Humans , Immunophenotyping , Mice , Mice, Nude , Microscopy, Electron , Neoplasm Transplantation , Neuroglia/cytology , Reproducibility of Results , Transplantation, Heterologous
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