296 research outputs found
Anxiolytic-like effects of nociceptin/orphanin FQ in the elevated plus maze and in the conditioned defensive burying test in rats
Different reports suggest that nociceptin/orphanin FQ (N/OFQ) may have either anxiolytic- or anxiogenic-like effect in rodents. Since N/OFQ elicits hypolocomotion, which undergoes rapid tolerance, and hypolocomotion may be associated to emotional consequences, the present study was designed to investigate the effect of N/OFQ on anxiety after development of tolerance to its hypolocomotor effect. The effect of single or double intracerebroventricular (i.c.v.) injection of N/OFQ was evaluated on anxiety-related behaviors in rats, in the elevated plus maze (EPM) and conditioned defensive burying (CDB) tests. After single administration, N/OFQ displayed an anxiogenic-like pattern of response on the elevated plus maze but hypolocomotion was also observed. Conversely, in the CDB test, N/OFQ induced a clear-cut anxiolytic pattern. To produce tolerance to N/OFQ-induced hypolocomotion the peptide was administered by two i.c.v. injections separated by 120 min; in these conditions it decreased the expression of anxiety-related behaviors in both tests without affecting locomotor activity. The nociceptin/orphanin FQ peptide (NOP) receptor antagonist UFP-101 significantly reduced the effects of N/OFQ to control values in either tests. Corticosterone levels were significantly increased after a single N/OFQ administration (not in a dose-dependent manner) but this increase did not reach significance after double administration (1 nmol/rat). Our results support the idea that N/OFQ may act as an anxiolytic-like agent in the rat; the apparent anxiogenic-like effect observed following its single administration in the EPM may be consequent to its, effect on locomotion. (c) 2006 Elsevier Inc. All rights reserved
SYNBIO® Probiotic and Antioxidant Dietary Supplementation: Clinical Trial Evaluation of Potential Effects on Airline Flight Crew Members' Well-Being
The irregular lifestyle of airline crew members, wide/adverse job-related exposures, and the impact of temporary hypoxia on gut microbiota well-being have increased concern about the daily recommended dose of certain nutrients among flight crew. The aim of this study was to determine if daily consumption of a SYNBIO (R) probiotics-elderberry extract supplement (ACTIVE) may contribute to the well-being of flight attendants. Forty healthy crew members enrolled in a double-blind, randomized, placebo-controlled study consumed one ACTIVE capsule/day or placebo for 30 days. Bowel well-being, health-related quality of life, and gastrointestinal tolerance were assessed by validated questionnaires. Saliva and fecal samples were analyzed to determine secretory immunoglobulin-A (sIgA) levels and to characterize gut microbiota composition, respectively. ACTIVE subjects presented a physiological improvement and a statistically significant higher Psychological General Well-Being Index (PGWBI) global score compared to PLACEBO subjects. The ACTIVE subjects showed significantly increased levels of lactobacilli and bifidobacteria compared to the PLACEBO group, while a significant increase in lactobacilli and a significant reduction in Enterobacteriaceae were registered when compared with the beginning of supplementation, confirming the persistence of probiotics in the gastrointestinal tract and the direct antagonism and competitive exclusion effects. Additionally, sIgA levels were significantly higher in the ACTIVE group compared to the baseline and to the PLACEBO group at the end of supplementation. The ACTIVE supplementation might be beneficial to airline crew members, improving their physiological state, their immune defenses, and the strength and efficiency of their gastrointestinal tract when responding to stressful conditions
Mixed modeling for large-eddy simulation: The single-layer and two-layer minimum-dissipation-Bardina models
Predicting the behavior of turbulent flows using large-eddy simulation
requires modeling of the subgrid-scale stress tensor. This tensor can be
approximated using mixed models, which combine the dissipative nature of
functional models with the capability of structural models to approximate
out-of-equilibrium effects. We propose a mathematical basis to mix (functional)
eddy-viscosity models with the (structural) Bardina model. By taking an
anisotropic minimum-dissipation (AMD) model for the eddy viscosity, we obtain
the (single-layer) AMD-Bardina model. In order to also obtain a
physics-conforming model for wall-bounded flows, we further develop this mixed
model into a two-layer approach: the near-wall region is parameterized with the
AMD-Bardina model, whereas the outer region is computed with the Bardina model.
The single-layer and two-layer AMD-Bardina models are tested in turbulent
channel flows at various Reynolds numbers, and improved predictions are
obtained when the mixed models are applied in comparison to the computations
with the AMD and Bardina models alone. The results obtained with the two-layer
AMD-Bardina model are particularly remarkable: both first- and second-order
statistics are extremely well predicted and even the inflection of the mean
velocity in the channel center is captured. Hence, a very promising model is
obtained for large-eddy simulations of wall-bounded turbulent flows at moderate
and high Reynolds numbers.Comment: 29 pages, 14 figures, 3 tables; revised, accepted manuscrip
CDC in brief 2013
With the start of the 113th Congress, we\u2019d like to take an opportunity to (re)introduce the Centers for Disease Control and Prevention (CDC), and provide some helpful information about our agency and its work. This E-Brief contains links to useful information about CDC\u2019s science, budget, and presence on the ground. For quick access to additional information about CDC\u2019s work, please contact the CDC Washington Office at (202) 245-0600, and see below for information about how CDC Washington can help you.CS238048-6What CDC does -- Fast facts -- CDC on the ground -- How can CDC Washington help you?201
EXTRA-HYPOTHALAMIC CRF-1 RECEPTOR MECHANISMS IN A MODEL OF BINGE-LIKE PALATABLE FOOD CONSUMPTION IN FEMALE RATS
Purpose: The present study evaluated the effect of the corticotrophin releasing factor (CRF)1 receptor antagonist R121919 and the corticosterone synthesis inhibitor metyrapone in female rats, in which binge eating for highly palatable food was evoked by frustration stress and cycles of food restrictions. Methods: We used 4 groups of rats that were first exposed or not exposed to repeated intermittent cycles of regular chow food restriction during which they were also given intermittent access to high-caloric palatable food. On the test day, we either exposed or did not expose the rats to the sight of the palatable food for 15 min, without allowing access to it (frustration stress) before assessing food consumption for 2 h. Results: We found that systemic injections of the CRF1 receptor antagonist R121919 but not of the metyrapone blocked binge-like eating behavior. Moreover, corticosterone injection did not induce binge eating in non-stressed rats. Restricted and stressed rats showed up regulation of CRH1 receptor mRNA signal in dorsal BNST and in CeA but not in PVN. Injection of CRF receptor antagonist D-Phe-CRF(12– 41) in CeA blocked binge-like eating behavior. Conclusions: These findings demonstrate that extra-hypothalamic CRF1 receptors, rather than those involved in endocrine functions, are involved in binge eating. Selective antagonism at CRF1 receptor may represent a novel pharmacological treatment for bingeing-related eating disorders
Olfactory receptor 984: a new target for obesity in rats and humans?
Aims: Obesity is a complex multifactorial and heterogeneous condition with an important genetic component matched with behavioral and environmental factors. Feeding behavior and body weight are controlled through complex interactions between the central nervous system (CNS) and peripheral organs. The aim of the present study was to identify and functionally characterize candidate gene/s involved in the development of resistance to diet-induced obesity (DIO) in rats.
Methods: RNA Chip-Technology and genotype analysis was done in 10 visceral adipose tissue samples of DR (n=5) and DIO (n=5) rats. The most promising candidate gene, OR6C3 (orthologous with the rat Olr984 and mouse Olfr788) was measured by quantitative real-time PCR in adipocytes and stromal vascular fraction (SVF) from paired samples of human visceral and subcutaneous adipose tissue (AT) (n=225). Moreover, Olfr788 expression in 3T3-L1 adipocytes was measured after treatment with various hormones and cytokines.
Results: Gene expression analyses showed Olr984 differently regulated in DIO-resistant rats. In the subcutaneous AT of human samples we found a down-regulation of OR6C3 compared to the visceral AT of the same population, independent of gender, glucose tolerance or type 2 diabetes. OR6C3 is more expressed in SVF than in adipocytes. Interestingly, treatment of 3T3-L1 cells with insulin decreased Olfr788 expression mRNA compared to untreated controls.
Conclusions: Olr984 is a novel candidate gene related to diet-induced obesity in rats. Moreover, variation in human mRNA expression in AT is related to obesity parameters and glucose homeostasis, which might be attributed to the regulatory role of insulin on the Olr984
Effects of the satiety signal oleoylethanolamide on binge-like food consumption in female rats
Several lines of evidence document the association between eating disorders and modern lifestyle, encompassing calorie-rich diets and psychological stress. Binge-eating disorder (BED) is a eating disorder characterized by excessive consumption of food in a short period of time, along with loss of control and psychological distress. Among the networks that partake in the neurobiological bases of BED a large body of evidence supports the activation of the hypothalamic-pituitary-adrenal stress (HPA) axis. Pharmacological treatments for BED are limited thus highlighting the need to identify novel targets that could lead to the development of more effective therapies. A large body of evidence has accumulated on the role played by the lipid signal oleoylethanolamide (OEA) as a pharmacological target for controlling aberrant eating disorders. As a drug, OEA reduces food intake and body weight gain in laboratory rodents by inducing a state of satiety. Additionaly, OEA dampens the hyperactivity of the HPA axis and ameliorates the effects of stress. On the bases of these premises, in the present study we investigated the effects of OEA on high palatable food (HPF) intake in a rat model of BED. Moreover, we assessed the impact of OEA on the corticotropin-releasing factor (CRF) system which plays a critical role in stress and on the oxytocinergic system which is crucial in mediating the pro-satiety effect of OEA. We used female rats with a history of intermittent food restriction which show binge-like palatable food consumption after the exposure to a “frustration stress”. On the test day, we either exposed or did not expose the rats to the sight of the palatable food (frustration stress) before assessing food consumption. OEA was administered at three different doses (2.5, 5, 10 mg/kg i.p.) and HPF intake was monitored over 2h. After the behavioural experiment brains were collected and in-situ hybridization experiment was performed to analyse CRF and oxytocin mRNA expression in selected brain areas. Our results demonstrate that OEA (10 mg/kg) was able to selectively prevent binge eating; the antibinge effect was accompained by a reduction of CRF mRNA within the central-amygdala. Finally, in keeping with our previous observations we found that the antibinge effect of OEA was accompanied by a significant increase of oxytocin mRNA at hypothalamic level. In the current study, we provide for the first time evidence to support that the endogenous fatty-gut lipid OEA exerts a selective inhibitory effects on binge-like eating behavior in female rats, supporting the hypothesis that OEA might represent a novel potential pharmacological target for the treatment of aberrant eating patterns
Pharmacological Inhibition of FAK-Pyk2 Pathway Protects Against Organ Damage and Prolongs the Survival of Septic Mice
Sepsis and septic shock are associated with high mortality and are considered one of the major public health concerns. The onset of sepsis is known as a hyper-inflammatory state that contributes to organ failure and mortality. Recent findings suggest a potential role of two non-receptor protein tyrosine kinases, namely Focal adhesion kinase (FAK) and Proline-rich tyrosine kinase 2 (Pyk2), in the inflammation associated with endometriosis, cancer, atherosclerosis and asthma. Here we investigate the role of FAK-Pyk2 in the pathogenesis of sepsis and the potential beneficial effects of the pharmacological modulation of this pathway by administering the potent reversible dual inhibitor of FAK and Pyk2, PF562271 (PF271) in a murine model of cecal ligation and puncture (CLP)-induced sepsis. Five-month-old male C57BL/6 mice underwent CLP or Sham surgery and one hour after the surgical procedure, mice were randomly assigned to receive PF271 (25 mg/kg, s.c.) or vehicle. Twenty-four hours after surgery, organs and plasma were collected for analyses. In another group of mice, survival rate was assessed every 12 h over the subsequent 5 days. Experimental sepsis led to a systemic cytokine storm resulting in the formation of excessive amounts of both pro-inflammatory cytokines (TNF-α, IL-1β, IL-17 and IL-6) and the anti-inflammatory cytokine IL-10. The systemic inflammatory response was accompanied by high plasma levels of ALT, AST (liver injury), creatinine, (renal dysfunction) and lactate, as well as a high, clinical severity score. All parameters were attenuated following PF271 administration. Experimental sepsis induced an overactivation of FAK and Pyk2 in liver and kidney, which was associated to p38 MAPK activation, leading to increased expression/activation of several pro-inflammatory markers, including the NLRP3 inflammasome complex, the adhesion molecules ICAM-1, VCAM-1 and E-selectin and the enzyme NOS-2 and myeloperoxidase. Treatment with PF271 inhibited FAK-Pyk2 activation, thus blunting the inflammatory abnormalities orchestrated by sepsis. Finally, PF271 significantly prolonged the survival of mice subjected to CLP-sepsis. Taken together, our data show for the first time that the FAK-Pyk2 pathway contributes to sepsis-induced inflammation and organ injury/dysfunction and that the pharmacological modulation of this pathway may represents a new strategy for the treatment of sepsis
Modulation of pain sensitivity by chronic consumption of highly palatable food followed by abstinence: emerging role of fatty acid amide hydrolase
There is a strong relationship between palatable diet and pain sensitivity, and the cannabinoid and opioid systems might play an important role in this correlation. The palatable diet used in many animal models of obesity is the cafeteria (CAF) diet, based on human food with high sugar, salt, and fat content. In this study, we investigated whether long-term exposure to a CAF diet could modify pain sensitivity and explored the role of the cannabinergic system in this modification. Male Sprague–Dawley rats were divided into two groups: one fed with standard chow only (CO) and the other with extended access (EA) to a CAF diet. Hot plate and tail flick tests were used to evaluate pain sensitivity. At the end of a 40-day CAF exposure, EA rats showed a significant increase in the pain threshold compared to CO rats, finding probably due to up-regulation of CB1 and mu-opioid receptors. Instead, during abstinence from palatable foods, EA animals showed a significant increase in pain sensibility, which was ameliorated by repeated treatment with a fatty acid amide hydrolase inhibitor, PF-3845 (10 mg/kg, intraperitoneally), every other day for 28 days. Ex vivo analysis of the brains of these rats clearly showed that this effect was mediated by mu-opioid receptors, which were up-regulated following repeated treatment of PF-3845. Our data add to the knowledge about changes in pain perception in obese subjects, revealing a key role of CB1 and mu-opioid receptors and their possible pharmacological crosstalk and reinforcing the need to consider this modulation in planning effective pain management for obese patients
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