52 research outputs found

    CCAP regulates feeding behavior via the NPF pathway in Drosophila adults

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    The intake of macronutrients is crucial for the fitness of any animal and is mainly regulated by peripheral signals to the brain. How the brain receives and translates these peripheral signals or how these interactions lead to changes in feeding behavior is not well-understood. We discovered that 2 crustacean cardioactive peptide (CCAP)-expressing neurons in Drosophila adults regulate feeding behavior and metabolism. Notably, loss of CCAP, or knocking down the CCAP receptor (CCAP-R) in 2 dorsal median neurons, inhibits the release of neuropeptide F (NPF), which regulates feeding behavior. Furthermore, under starvation conditions, flies normally have an increased sensitivity to sugar; however, loss of CCAP, or CCAP-R in 2 dorsal median NPF neurons, inhibited sugar sensitivity in satiated and starved flies. Separate from its regulation of NPF signaling, the CCAP peptide also regulates triglyceride levels. Additionally, genetic and optogenetic studies demonstrate that CCAP signaling is necessary and sufficient to stimulate a reflexive feeding behavior, the proboscis extension reflex (PER), elicited when external food cues are interpreted as palatable. Dopaminergic signaling was also sufficient to induce a PER. On the other hand, although necessary, NPF neurons were not able to induce a PER. These data illustrate that the CCAP peptide is a central regulator of feeding behavior and metabolism in adult flies, and that NPF neurons have an important regulatory role within this system

    Burkitt lymphoma with a granulomatous reaction: an M1/Th1-polarised microenvironment is associated with controlled growth and spontaneous regression

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    Aims: Burkitt lymphoma (BL) is an aggressive B-cell lymphoma that, in some instances, may show a granulomatous reaction associated with a favourable prognosis and occasional spontaneous regression. In the present study, we aimed to define the tumour microenvironment (TME) in four such cases, two of which regressed spontaneously. Methods and results: All cases showed aggregates of tumour cells with the typical morphology, molecular cytogenetics and immunophenotype of BL surrounded by a florid epithelioid granulomatous reaction. All four cases were Epstein–Barr virus (EBV)-positive with type I latency. Investigation of the TME showed similar features in all four cases. The analysis revealed a proinflammatory response triggered by Th1 lymphocytes and M1 polarised macrophages encircling the neoplastic cells with a peculiar topographic distribution. Conclusions: Our data provide an in-vivo picture of the role that specific immune cell subsets might play during the early phase of BL, which may be capable of maintaining the tumour in a self-limited state or inducing its regression. These novel results may provide insights into new potential therapeutic avenues in EBV-positive BL patients in the era of cellular immunotherapy

    Burkitt lymphoma with granulomatous reaction: A M1/TH1‐polarized microenvironment associates with controlled growth and spontaneous regression

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    AIMS: Burkitt lymphoma (BL) is an aggressive B-cell lymphoma, which in some instances, may show a granulomatous reaction associated with a favourable prognosis and occasional spontaneous regression. In the present study, we aimed to define the tumour microenvironment (TME) in four of such cases, two of which regressed spontaneously. METHODS AND RESULTS: All cases showed aggregates of tumour cells with the typical morphology, molecular cytogenetics and immunophenotype of BL surrounded by a florid epithelioid granulomatous reaction. All four cases were Epstein-Barr virus (EBV) positive with type I latency. The investigation of the tumour microenvironment (TME) showed similar features in all four cases. The analysis revealed a pro-inflammatory response triggered by Th1 lymphocytes and M1 polarized macrophages encircling the neoplastic cells with a peculiar topographic distribution. CONCLUSIONS: Our data provide an in vivo picture of the role that specific immune cell subsets might play during the early phase of BL, which may be capable of maintaining the tumour in a self-limited state or inducing its regression. These novel results may provide insights to explore new potential therapeutic avenues in EBV-positive BL patients in the era of cellular immunotherapy

    In Vivo Methods to Study Uptake of Nanoparticles into the Brain

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    Several in vivo techniques have been developed to study and measure the uptake of CNS compounds into the brain. With these techniques, various parameters can be determined after drug administration, including the blood-to-brain influx constant (Kin), the permeability-surface area (PS) product, and the brain uptake index (BUI). These techniques have been mostly used for drugs that are expected to enter the brain via transmembrane diffusion or by carrier-mediated transcytosis. Drugs that have limitations in entering the brain via such pathways have been encapsulated in nanoparticles (based on lipids or synthetic polymers) to enhance brain uptake. Nanoparticles are different from CNS compounds in size, composition and uptake mechanisms. This has led to different methods and approaches to study brain uptake in vivo. Here we discuss the techniques generally used to measure nanoparticle uptake in addition to the techniques used for CNS compounds. Techniques include visualization methods, behavioral tests, and quantitative methods

    Tolerance develops to the behavioural effects of ACTH-(1-24) during continuous i.c.v. infusion in rats, and is associated with increased hypothalamic levels of beta-endorphin.

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    In rats, the continuous infusion of ACTH-(1-24) into a brain lateral ventricle (0.5 micrograms/h in the volume of 1.11 microliters, for 7 days) caused a significant inhibition of the subsequent behavioural response to the acute intracerebroventricular injection of the same peptide. Tolerance developed to all the most typical signs of the ACTH-induced behavioural syndrome (grooming, stretching, yawning, penile erection, inhibition of food intake), and was associated with a significant increase in the hypothalamic levels of beta-endorphin immunoreactivity

    L-sulpiride, at antidepressant dosage, prevents conditioned-fear stress-induced gastric lesions in rats

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    It has been previously shown that long-term treatment with low doses of L-sulpiride is highly effective in rat models of depression and of anticipatory anxiety/panic behavior. The present study was aimed at investigating whether the same treatment can prevent the ulcerogenic effect of repeated inescapable stresses. In adult rats, the repeated (7 consecutive days) exposure to an uncontrollable stressful condition (inescapable 2.5 mA scrambled shock for 60 s) produced the development of gastric lesions (multiple punctiform telangiectasias in all rats, with superficial erosions or more severe ulcerations in 10 out 13 rats; score 4.67 +/- 0.44). L-sulpiride, intraperitoneally injected once a day at an antidepressant dose level (4 mg kg(-1) per day), starting 21 days before the beginning of the 7-day sequence of inescapable punishments (= 28 daily treatments), almost completely prevented the stress-induced gastric injury (score 1.67 +/- 0.29; P < 0.001 vs saline-treated rats, Mann-Whitney U test). These results show that, in rats, a long-term treatment with low doses of L-sulpiride prevents the development of gastric lesions induced by chronic exposure to uncontrollable stress. (C) 2000 Academic Press
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