Alterations in the masseter muscle and plasma IL-6 level following experimentally induced occlusal interference and chronic stress--a study in rats

This study was undertaken to examine the alteration of masseter and plasma interleukin-6 after inducing occlusal interference and chronic stress. Male Wistar rats were submitted to chronic stress procedure, exposed to occlusal interference, or exposed to both mentioned procedures. Whole blood and masseter tissue were collected to determine interleukin-6 level, measured by means of ELISA. Masseter pain was evaluated using the orofacial formalin test. Masseter interleukin-6 level was significantly higher in animals submitted to combination of occlusal interference and chronic stress than in the control group (p<0.05). There was positive and significant correlation between pain response and masseter interleukin-6 level (r=0.5741; p<0.0003). No significant differences in plasma interleukin-6 level were found between groups (p>0.05), as well as no correlation with pain (p>0.05). Combination of occlusal interference and chronic stress leads to strong local reaction characterized by high levels of masseter interleukine-6. High concentrations of muscle interleukin-6 and its correlation with pain point to inflammatory background of masticatory muscle pain.     

Possible role of RKIP in cytotrophoblast migration: immunohistochemical and in vitro studies

Raf kinase inhibitor protein (RKIP) regulates growth and differentiation signaling of mitogen-activated protein kinases (MAPK), GRK2 and NF-kappaB pathways each of which regulates cytotrophoblast differentiation and normal placental development. We show here that RKIP is expressed in human normal and preeclampic placentas as detected by immunostaining. RKIP was detected in villous cytotrophoblast in normal placenta and switched to syncytiotrophoblast in pre-eclampsia (PE)-complicated pregnancies. RKIP was also localized in extravillous cytotrophoblast of cell islands and cell columns both in normal and in PE placentas, although staining was less uniform in the latter specimens. In order to test RKIP involvement in cytotrophoblast function, we performed in vitro studies on HTR-8/SVneo cells, a first trimester cytotrophoblast cell line. We show that the RKIP inhibitor locostatin reduces ERK phosphorylation and impairs HTR-8/SV neo cells motility in wound closure experiments. We also document the presence of GRK2 mRNA, the reduction of phosphorylated RKIP expression by locostatin and the induction of PAI mRNA expression in HTR-8/SV neo cells, suggesting the involvement of GRK2 and NF-kappaB pathways in these cells. In conclusion, our work provides evidence that RKIP is a novel factor expressed in cytotrophoblast cells where it likely regulates cell migration.     

β₂ long-acting and anticholinergic drugs control TGF-β1-mediated neutrophilic inflammation in COPD

We quantified TGF-β1 and acetylcholine (ACh) concentrations in induced sputum supernatants (ISSs) from 18 healthy controls (HC), 22 healthy smokers (HS) and 21 COPDs. ISSs from HC, HS and COPD as well as rhTGF-β1 were also tested in neutrophil adhesion and in mAChR2, mAChR3 and ChAT expression experiments in human bronchial epithelial cells (16-HBE). Finally, we evaluated the effects of Olodaterol (a novel inhaled β(2)-adrenoceptor agonist) and Tiotropium Spiriva?, alone or in combination, on neutrophil adhesion and mAChRs and ChAT expression in stimulated 16-HBE. The results showed that 1) TGF-β1 and ACh concentrations are increased in ISSs from COPD in comparison to HC and HS, and TGF-β1 in HS is higher than in HC; 2) ISSs from COPD and HS caused increased neutrophil adhesion to 16-HBE when compared to ISSs from HC. The effect of ISSs from COPD was significantly reduced by TGF-β1 depletion or by the pretreatment with Olodaterol or Tiotropium alone or in combination, while the effect of ISSs from HS was significantly reduced by the pretreatment with Olodaterol alone; 3) mAChR2, mAChR3 and ChAT expression was increased in 16-HBE stimulated with ISSs from COPD and TGF-β1 depletion significantly reduced this effect on mAChR3 and ChAT expression; 4) rhTGF-β1 increased mAChR2, mAChR3 and ChAT expression in 16-HBE; 5) Olodaterol did not affect the expression of mAChRs and ChAT in 16-HBE. Our findings support the use of β? long-acting and anticholinergic drugs to control the bronchoconstriction and TGF-β1-mediated neutrophilic inflammation in COPD.     

Chronic methylphenidate administration alters antioxidant defenses and butyrylcholinesterase activity in blood of juvenile rats

Methylphenidate (MPH), a psychostimulant that affects both dopaminergic and noradrenergic systems, is one of the most frequently prescribed treatments for attention-deficit hyperactivity disorder. The present study investigated the effects of chronic administration of MPH on some parameters of oxidative stress, as well as on butyrylcholinesterase (BuChE) activity in blood of young rats. Rats received intraperitoneal injections of MPH (2.0 mg/kg) once a day, from the 15th to the 45th day of age or an equivalent volume of 0.9% saline solution (controls). Two hours after the last injection, animals were euthanized, and blood was collected. Results demonstrated that MPH did not alter the dichlorofluorescein formed, decreased both thiobarbituric acid reactive substances and total non-enzymatic radical-trapping antioxidant, and increased superoxide dismutase and catalase activities, suggesting that this psychostimulant may alter antioxidant defenses. BuChE activity was increased in blood of juvenile rats subjected to chronic MPH administration. These findings suggest that MPH may promote peripheral oxidative adaptations and cholinergic changes.     

IL-1RN VNTR polymorphism and genetic susceptibility to cervical cancer in Portugal

Human Papillomavirus infection is considered as the main etiological factor of cervical cancer (ICC), although, the role of host genetic factors in ICC susceptibility has been increasing. Immunological response is crucial for the prevention of viral associated diseases. Interleukin 1 receptor antagonist (IL-1RN) is considered to be an important regulator of host immunity and several studies have shown a potential role of a 86?bp VNTR polymorphism within intron 2 of the IL-1RN gene in host immune response variability. We investigated the role of this polymorphism in cervical cancer development in Portugal with a case–control study developed with peripheral blood samples from 196 healthy women and 340 women with cervical lesions from the Northern Region of Portugal. We observed that IL-1RN Allele 2 homozygosis was significantly higher in cases than in controls. In fact, IL-1RN A2*A2 homozygous revealed to be associated with an increased risk of HSIL?+?ICC (OR?=?1.90; 95?% IC 1.13–3.21; p?=?0.015). Furthermore, we also observed that median age of onset of HSIL?+?ICC was significantly different (46.0 vs 52.0) in IL-1RN A2*A2 homozygous comparing to non-A2*A2 (p?=?0.028). Our results indicated that IL-1RN A2 allele is associated with an increased susceptibility to cervical cancer development, probably by increasing predisposition to shorter immune responses.     

Quercetin and epigallocatechin gallate effects on the cell membranes biophysical properties correlate with their antioxidant potential

Quercetin and epigallocatechin gallate are two of the most abundant polyphenols in dietary plants, including apples, onions, red wine and green tea. The bioactivity of polyphenols is linked to their ability to interact with cell membranes without being internalized. The aim of the present study was to assess the short-time effect of these polyphenols on membrane anisotropy and transmembrane potential of U937 monocytes and Jurkat T lymphoblasts. Results showed that quercetin and epigallocatechin gallate induced, after 20 minutes cell exposure, a dose-dependent increase of membrane anisotropy and polarization. Anisotropy increase was correlated with the reduction of lipid peroxidation. Our results could indicate that the antioxidant capacity of the tested polyphenols is due to their stabilizing effect on the cell membranes, thus contributing to cell protection in various pathologies and as adjuvant therapy in highly toxic treatment regimens.     

Deconstructing the complexity of a microenvironmental niche

Cells acquire their fate in?vivo in the context of a complex microenvironmental "niche" comprised of?heterologous cell types, signaling molecules, extracellular matrix, biophysical forces, and metabolic substrates. Now Calderón and Boehm report the "refunctionalization" of a defective thymic epithelial niche, offering insights into how signaling molecules may be hierarchically organized to direct differentiation outcomes.     

Simultaneous detection of infectious human echoviruses and adenoviruses by an in situ nuclease-resistant molecular beacon-based assay

A multiplex methodology using two nuclease-resistant molecular beacons that target specific genomic regions of adenovirus 2 and echovirus 17 during simultaneous infection in A549 cells is presented. Using fluorescence microscopy, visualization of enteroviral and adenoviral replication was possible within 3 h postinfection.