Interleukin-8 mRNA synthesis and protein secretion are continuously up-regulated by respiratory syncytial virus persistently infected cells

The aim of this study was to investigate whether respiratory syncytial virus persistence regulates interleukin 8 (IL-8) mRNA synthesis and protein secretion in a human lung epithelial cell line (A549). Therefore, we established RSV persistence in these cells (A549per) and determined the levels of interleukin-8 mRNA by RT-PCR and of protein through ELISA. Interleukin-8 mRNA synthesis and protein secretion were continuously up-regulated in A549per cells during passages and in A549 cells that had been incubated with supernatants (cA549per) obtained from A549per passages. These results suggested that the enhancement of interleukin-8 was stimulated either by the presence of the RSV genome in the cell or by soluble mediator(s) induced by RSV, which, in turn, increased interleukin-8 mRNA synthesis and protein secretion. Soluble RSV F and G proteins were identified as mediators. Moreover, interleukin-8 enhancement was observed after 1-min incubation with the soluble mediators, thus suggesting that interleukin-8 up-regulation was triggered by receptor-ligand interaction.     

Somatic embryogenesis of Agave victoria-reginae Moore

Plant regeneration through direct somatic embryogenesis of leaf blade explants from in vitro propagated plants of Agave victoria-reginae Moore, is described. Somatic embryogenesis was evident in a 6-week period on agarsolidified MS medium supplemented with L2 vitamins and 2,4-dichlorophenoxyacetic acid (1,4 µM), and germination of somatic embryos was achieved after 8 weeks on half-strength MS medium and 4 weeks on half-strength SH medium, both lacking growth regulators. Hyperhydricity of somatic embryos and plantlets was reduced by the use of vented culture vessel lids during the last 4 weeks on SH medium. Shoot proliferation was obtained, and hyperhydricity was eliminated on a modified MS medium (with NH₄NO₃ reduced to 5 mN) supplemented with kinetin (4.6 µM) and 1-naphthaleneacetic acid (1.6 µM) and the use of vented culture vessel lids.Abbreviations 2,4-d 2,4-dichlorophenoxyacetic acid - NAA 1-naphthaleneacetic acid - MS Murashige and Skoog - LOG-1 MS modified medium by Castro-Concha et al. (1990) - L2 Phillips and Collins (1979) vitamins - SH Schenk and Hildebrandt     

Anxiety-like behavior induced by IL-1beta is modulated by alpha-MSH through central melanocortin-4 receptors

The proinflammatory cytokine interleukin-1beta (IL-1beta) influences neuroendocrine activity and produces other effects, including fever and behavioral changes such as anxiety. The melanocortin neuropeptides, such as alpha-melanocyte-stimulating hormone (alpha-MSH), antagonize many actions of IL-1, including fever, anorexia and hypothalamic-pituitary-adrenal (HPA) axis activation through specific melanocortin receptors (MC-R) in the central nervous system. The objective of the present study was to establish the effect of MSH peptides on IL-1beta-induced anxiety-like behavior and the melanocortin receptors involved. We evaluated the effects of intracerebroventricular (i.c.v.) administration of IL-1beta (30 ng) and melanocortin receptor agonists: alpha-MSH, an MC3/MC4-R agonist (0.2 microg) or gamma-MSH, an MC3-R agonist (2 microg) or HS014, an MC4-R antagonist (2 microg), on an elevated plus-maze (EPM) test. Injection of IL-1beta induced an anxiogenic-like response, as indicated by reduced open arms entries and time spent on open arms. The administration of alpha-MSH reversed IL-1beta-induced anxiety with co-administration of HS014 inhibiting the effect of alpha-MSH. However, the associated treatment with gamma-MSH did not affect the anxiety response to IL-1beta. These data suggest that alpha-MSH, through central MC4-R can modulate the anxiety-like behavior induced by IL-1beta.     

Characterization of free fatty acid receptors expression in an obesity rat model with high sucrose diet

Introduction/aims: In recent years, it has been shown that free fatty acids receptors (FFAR) of whose function in the cell surface plays a significant role in the regulation of cell function and nutrition as well are activated by various endogenous ligands, but mainly by fatty acids. Within FFAR of our interest are GPR 41, 43 and 120. The functions of these receptors are varied and dependent on the tissue where they are. The activation and signaling of these receptors, FFAR, are involved in many physiological processes, and currently the target of many drugs in metabolic disorders like obesity, diabetes and atherosclerosis.

Material and methods: Obesity was induced with hypercaloric diet (HD) in male Wistar rats for 20?weeks (n?=?10). At the end, adipose tissue (abdominal and subcutaneous) was taken to perform assays for relative quantification mRNA expression by end-point RT-PCR and protein level expression by Western blot.

Results: These present data have shown for the first time that total mRNA isolation and protein expression from both adipose tissues (abdominal and subcutaneous) of rat in obesity condition yield significative statistical difference among the control versus obese groups, showing that the diet high in carbohydrates modifies the total presence of mRNA and protein level expression of the receptors GPR41, 43 and 120.

Conclusions: Further comparative methods are in process to clarify whether or not the obesity changes the functional receptors in these two tissues for new pharmacological approaches.     

Comparative histology of the digestive tract in three new world marsupials

We compare the main histological features of the digestive tract of three selected New World didelphid marsupials (Mammalia, Metatheria, Didelphimorphia, Didelphidae): the White-eared Opossum Didelphis albiventris Lund, 1840, the Short-tailed Opossum Monodelphis dimidiata Wagner, 1847, and the Patagonian Opossum Lestodelphys halli Thomas, 1921. The three species have a geographic distribution restricted to south-eastern and southern South America, and have quite distinct body masses, adaptations and life histories. Our observations include the following: (i) submucosal glands are present throughout the oesophagus of D. albiventris, only in its first third in M. dimidiata, and are lacking in L. halli; (ii) in the stomach and duodenum, the serus coat coat in D. albiventris is cuboidal (simple, squamous mesothelial layer in the other two species); (iii) the duodenum in L. halli has large folds, short crypts and Brunner's glands (the other species lack folds and Brunner's glands); (iv) the colon's mucous membrane has short, scarce villi in D. albiventris (villi absent in the remaining species). Some of the observed differences can be due to ecological adaptations, especially in the relatively large-sized, extremely omnivorous D. albiventris (e.g., colon villi).