Neuropeptide Y

Hyperprolactinemia and hyperleptinemia occur during gestation and lactation with marked hyperphagia associated with leptin resistance. Prolactin (PRL) induces the expression of orexigenic neuropeptide Y (NPY) through the activation of JAK-2/STAT-3 signaling pathway in hypothalamic paraventricular nucleus (PVN) leading to hyperphagia. PRL may also act through the inhibition of anorexigenic effect of leptin via induction of suppressor of cytokine signaling 3 (SOCS-3). This paper aimed to co-localize PRL (PRL-R) and leptin (ObRb) receptors in the hypothalamus of female rats and investigate the possible cross-desensitization between PRL-R and ObRb. We showed that: 1) PRL-R and ObRb are expressed in the PVN and co-localized in the same neurons; 2) in lactating females leptin failed to activate JAK-2/STAT-3 signaling pathway; 3) in Chinese Hamster Ovary (CHO) stably co-expressing PRL-R and ObRb, overexposure to PRL did not affect leptin signaling but totally abolished PRL-dependent STAT-5...

We studied the regulation of brain acetyl CoA carboxylase (ACC) activity during food deprivation and under the influence of hormones of glucose homeostasis: glucagon and insulin. Mice were deprived of food and water for time periods of 1, 3, 6, 9, 12 and 24 hours and were then allowed to re-feed for 5, 30 and 60 minutes. Mice that were deprived for up to 6 h, and then re-fed for 60 min, consumed the same amount of food compared to the ad libitum (control) animals. However, after 9 h of deprivation, mice consumed only 50% of food present even after 1 h of re-feeding, compared to the controls. The ACC activity was measured in the whole mouse brain of controls and after 1, 3, 6, 9, 12, and 24 h of food deprivation. Brain extracts assayed from control mice expressed an ACC activity of 0.988 +/- 0.158 fmol/min/mg tissue without citrate and 0.941 +/- 0.175 fmol/min/mg tissue with citrate. After 1 h of food deprivation, the total ACC activity without citrate decreased to 0.575 +/- 0.087 fm...

Bombesin receptors are overexpressed on a variety of human tumors like prostate, breast, and lung cancer. The aim of this study was to develop radiolabeled (Indium-111, Lutetium-177, and Yttrium-90) bombesin analogues with affinity to the three bombesin receptor subtypes for targeted radiotherapy. The following structures were synthesized: diethylenetriaminepentaacetic acid-␥-aminobutyric acid-[D-Tyr 6 , ␤-Ala 11 , Thi 13 , Nle 14 ] bombesin (6 -14) (BZH1) and 1,4,7,10-tetraazacyclododecane-N,N,N؆,Nٟ -tetraacetic acid-␥-aminobutyric acid-[D-Tyr 6 , ␤-Ala 11 , Thi 13 , Nle 14 ] bombesin (6 -14) (BZH2). [ 111 In]-BZH1 and in particular [ 90 Y]-BZH2 were shown to have high affinity to all three human bombesin receptor subtypes with binding affinities in the nanomolar range. In human serum metabolic cleavage was found between ␤-Ala 11 and His 12 with an approx- imate half-life of 2 hours. The metabolic breakdown was inhibited by EDTA and ␤-Ala 11 -His 12 (carnosine) indicating that carnosinase is the active enzyme. Both 111 In-labeled peptides were shown to internalize into gastrinreleasing peptide-receptor-positive AR4 -2J and PC-3 cells with similar high rates, which were independent of the radiometal. The biodistribution studies of [ 111 In]-BZH1 and [ 111 In]-BZH2 ([ 177 Lu]-BZH2) in AR4 -2J tumor-bearing rats showed specific and high uptake in gastrin-releasing peptide-receptor-positive organs and in the AR4 -2J tumor. A fast clearance from blood and all of the nontarget organs except the kidneys was found. These radiopeptides were composed of the first pan-bombesin radioligands, which show great promise for the early diagnosis of tumors bearing not only gastrin-releasing peptide-receptors but also the other two bombesin receptor subtypes and may be of use in targeted radiotherapy of these tumors.

To determine the distribution of NPY and TH human choroidal innervation, choroidal whole-mounts were processed for indirect immunofluorescence. An antibody to a component of the neuronal cytoskeleton, neurofilament 200 kDa (NF-200) was used to identify neurons and axons. A double immunostaining was performed, antibodies against NF-200 being combined with antibodies against neuropeptide Y (NPY) and tyroxine hydroxylase (TH). Fibers containing both NPY and TH were distributed in three plexuses, one in the suprachoroid large-sized vessel layer, and two in the medium-sized vessel layer. Intrinsic choroidal neurons (ICNs) containing NPY and TH were observed in the suprachoroid. The TH(+) ICNs were located in the medium-sized vessel layer. Overall, NPY(+) and TH(+) ICNs were more frequent in the central temporal area, both in isolation and forming microganglia. We also detected small spindle elements intensely immunoreactive to TH(+) and distributed mainly in the suprachoroid from the equ...

Mesial temporal lobe epilepsy (MTLE) is the most common form of intractable seizure disorder in adults. It is associated with an asymmetrical pattern of neuron loss within the hilus and CA1 hippocampal subfields, with relative sparing of the dentate granule neurons and the CA2 subfields. The amygdalar nuclei and the cortical neurons are other areas that are rarely involved in MTLE. 1 The neuropathological changes that bring about focally evoked seizures in the adult are thought to begin in the early stages of neonatal life. A wide range of factors have been implicated in the causation of MTLE, such as febrile seizures and traumatic brain injury. 2 Some studies indicate that up to 74% of those who experience early life status epilepticus develop epilepsy at a later stage. 2 The objective of this study is to investigate the neuropathological changes induced by intra-amygdalar kainic acid (KA) microinjection in a postnatal day 10 (P10) rat model of Seizure induction by intra-amygdalar microinjection of KA was modified from experimental models developed by Henshall et al. 4 Pups received either 2µl of vehicle (phosphate buffer, pH 7.4; n=4) or 2µl KA (n=4). EEG was recorded for up to 90 minutes, during which behaviour associated with inter-ictal events were monitored. Immunofluorescence microscopy was performed on fresh frozen rat brains for glial fibrillary acidic protein (GFAP) (1:400), a marker of astrogliosis, and neuronal nuclei (NeuN) (1:400), a marker of neuronal nuclei. Flurojade B staining (FjB) was also performed to assay for neuronal cell death. Statistical analysis was carried out using non-paired student t-tests. Following injection of 2µg of KA, initial low amplitude, high frequency EEG developed to high amplitude, high frequency epileptiform EEG seizures consistent with status epilepticus. All KA-treated pups (n=4) displayed seizure-like behaviour, including initial masticatory movements and salivation, developing periods of forelimb myoclonus and progressing to wild swimming behaviours. Histological analysis of the rat brains treated with KA showed a reduction of the overall size of the ipsilateral hippocampus as well as atrophy of the pyramidal cell layers. Hydrocephalus ex vacuo of the ipsilateral lateral ventricle was also noted in one of four rat brains. Ipsilateral P10 CA3 NeuN counts in KA-treated rats were approximately 75% of that in the control group (n=4, p<0.01), demonstrating preferential CA3 subfield-specific neuronal cell death in KA-treated pups. Ipsilateral FjB-positive cell counts in treated animals were approximately 20 times greater than in the control animals (n=4, p<0.05). In addition, there was diffuse astrogliosis in the ipsilateral hippocampus of treated animals.

Adenosine modulates a variety of cellular functions including calcium-dependent exocytosis. Activation of adenosine A2A receptor (A2A-R) facilitates neurotransmitter release in some cell types, although the underlying mechanisms are not fully understood. In this study, we found that treatment of PC12 cells with the A2A-R agonist CGS21680 promotes calcium-evoked secretion of the fusion protein between neuropeptide Y and modified yellow fluorescence protein (NPY-Venus). CGS21680 treatment of PC12 cells transiently increased the phosphorylation of p38 and JNK MAP kinases and Akt, as well as that of ATF2 and CREB, reaching maximal levels at around 10-15 min of CGS21680 treatment. Importantly, pretreatment of PC12 cells with the PI3K inhibitor LY294002, together with the protein kinase A (PKA) inhibitor KT5720, significantly inhibited CGS21680 enhancement of calcium-dependent NPY-Venus release. Moreover, expression of a dominant-negative form of Akt and the PKA inhibitory polypeptide protein kinase inhibitor (PKI) co-operatively inhibited the facilitating effect of CGS21680 on secretion of NPY-Venus. These data suggest that the PI3K-Akt and PKA pathways play a critical role in A2A-R-mediated facilitation of calcium-dependent secretion. We also found that CGS21680 treatment promoted recruitment of the NPY-Venus-containing vesicles to the proximity of the plasma membrane at around 10-15 min of CGS21680 treatment, which may in part account for the facilitated secretion by A2A-R activation.

The neuropeptide Y family of peptides, which includes neuropeptide Y (NPY), peptide YY (PYY), and pancreatic polypeptide (PP), are found in the central and peripheral nervous system and display a wide array of biological activities. These actions are believed to be mediated through pharmacologically distinct G protein-coupled receptors, and, to date, three members of the NPY receptor family have been cloned. In this study we describe the cloning and expression of a novel NPY receptor from mouse genomic DNA. This receptor, designated NPY Y5, shares 60% amino acid identity to the murine NPY Y1 receptor. The pharmacology of this novel receptor resembles that of the NPY Y1 receptor and is distinct from that described for the NPY Y2, Y3, and Y4 receptors. In situ hybridization of mouse brain sections reveals expression of this receptor within discrete regions of the hypothalamus including the suprachiasmatic nucleus, anterior hypothalamus, bed nucleus stria terminalis, and the ventromedial nucleus with no localization apparent elsewhere in the brain.

This article summarizes the proceedings of a symposium held at the conference on "Alcoholism and Stress: A Framework for Future Treatment Strategies" in Volterra, Italy, May 6-9, 2008. Chaired by Markus Heilig and Roberto Ciccocioppo, this symposium offered a forum for the presentation of recent data linking neuropetidergic neurotransmission to the regulation of different alcohol related behaviours in animals and in humans. Dr. Donald Gehlert described the development of a new corticotrophin releasing factor (CRH) receptor 1 antagonist and showed its efficacy in reducing alcohol consumption and stress-induced relapse in different animal models of alcohol abuse. Dr. Andrey Ryabinin reviewed recent findings in his laboratory indicating a role of the urocortin 1 (Ucn) receptor system in the regulation of alcohol intake. Dr. Annika Thorsell showed data supporting the significance of the neuropetide Y (NPY) receptor system in the modulation of behaviours associated with a history of ethanol intoxication. Dr. Roberto Ciccocioppo focused his presentation on the nociceptin/orphanin FQ (N/OFQ) receptors as treatment targets for alcoholism. Finally, Dr. Markus Heilig showed recent preclinical and clinical evidence suggesting that neurokinin 1 (NK1) antagonism may represent a promising new treatment for alcoholism. Collectively, these investigators highlighted the significance of neuropeptidergic neurotransmission in the regulation of

The mole rat, Cryptomys hottentotus (Bathyergidae) is a gregarious subterranean rodent, which shows no entrainment to ambient light-dark cycles. The locomotor activity of individuals or of a whole colony, which shows no circadian rhythmicity. Since the lack of both synchronization to light-dark cycle and an endogenous rhythm of locomotor activity could be related to the organization of the circadian system, we have investigated the neuropeptidergic features of the SCN and IGL, and have used pseudorabies viral tracing methods to identify the visual and circadian pathways in this species. The precise topographic distribution of certain neuropeptide populations in the SCN differs from typical rodent pattern of organization and may be correlated with the apparent absence of light entrainment of activity and lack of endogenous rhythmicity. The IGL is highly reduced in size. This structure can nevertheless be identified by the presence of NPY and CALB positive neurons, as well as by a dense network of SP fibers. Viral tracing using intraocular injection of the PRV-Becker and PRV-Bartha strains, leads to differential infection of neurons in circadian and visual structures. With the Bartha strain, infected neurons are principally observed in the SCN, whereas the Becker strain leads primarily to infection of the dLGN and shows an anatomical regression of visual structures. Transsynaptic retrograde infection of the retina contralateral to the injected eye reveals a morphologically homogeneous population, which resemble to retinohypothalamic ganglion cells described in other mammals.

Neuropeptide Y (NPY) plays an important role in regulating appetite and hunger in vertebrates. In the hypothalamus, NPY stimulates food intake under the control of the nutritional status. Previous studies have shown the presence of NPY and receptors in rodent olfactory system, and suggested a neuroproliferative role. Interestingly, NPY was also shown to directly modulate olfactory responses evoked by a food-related odorant in hungry axolotls. We have recently demonstrated that another nutritional cue, insulin, modulates the odorant responses of the rat olfactory mucosa (OM). Therefore, the aim of the present study was to investigate the potential effect of NPY on rat OM responses to odorants, in relation to the animal's nutritional state. We measured the potential NPY modulation of OM responses to odorant, using electro-olfactogram (EOG) recordings, in fed and fasted adult rats. NPY application significantly and transiently increased EOG amplitudes in fasted but not in fed rats. The effects of specific NPY-receptor agonists were similarly quantified, showing that NPY operated mainly through Y1 receptors. These receptors appeared as heterogeneously expressed by olfactory neurons in the OM, and western blot analysis showed that they were overexpressed in fasted rats. These data provide the first evidence that NPY modulates the initial events of odorant detection in the rat OM. Because this modulation depends on the nutritional status of the animal, and is ascribed to NPY, the most potent orexigenic peptide in the central nervous system, it evidences a strong supplementary physiological link between olfaction and nutritional processes.

The blind mole rat, Spalax, is a subterranean rodent with atrophied, subcutaneous eyes. Whereas most of the visual system is highly degenerated, the retino-hypothalamic pathway in this species has remained intact. Although Spalax is considered to be visually blind, circadian locomotor rhythms are entrained by the light/dark cycle. In the present study we used anterograde tracing techniques to demonstrate retinal afferents to the suprachiasmatic nucleus (SCN) and immunohistochemistry to examine the distribution of neuropeptides that are known to be involved in the regulation or expression of circadian rhythmicity. Based on the localization of retinal afferents and neuropeptides, the SCN can be divided into two subdivisions. The ventral region, which receives retinal afferents, also contains vasoactive intestinal polypeptide (VIP)-containing neurons, and fibers that are immunopositive to neuropeptide Y (NPY) and serotonin (5-HT). The dorsal region contains vasopressinergic neurons, but this latter cell population is extremely sparse compared to that described in other rodents. The dorsal region is also characterized by numerous VIP-immunoreactive fibers. The presence of NPY and 5-HT fibers suggests that the SCN receives afferent projections from the intergeniculate leaflet and from the raphe nuclei, respectively. These neuroanatomical results, together with previous studies of behavior, visual tract tracing, and immediate early gene expression, confirm that an endogenous clock and the capacity for light entrainment of circadian rhythms are conserved in the blind mole rat.

The aim of the present study was to investigate the presence of sympathetic innervation in human muscle spindles, using antibodies against neuropeptide Y (NPY), NPY receptors and tyrosine hydroxylase (TH). A total of 232 muscle spindles were immunohistochemically examined. NPY and NPY receptors were found on the intrafusal fibers, on the blood vessels supplying muscle spindles and on free nerve endings in the periaxial space. TH-immunoreactivity was present mainly in the spindle nerve and vessel. This is, to our knowledge, the first morphological study concerning the sympathetic innervation of the human muscle spindles. The results provide anatomical evidence for direct sympathetic innervation of the intrafusal fibers and show that sympathetic innervation is not restricted to the blood vessels supplying spindles. Knowledge about direct sympathetic innervation of the muscle spindle might expand our understanding of motor and proprioceptive dysfunction under stress conditions, for example, chronic muscle pain syndromes.

The neuropeptides substance P, calcitonin gene-related peptide (CGRP) and vasoactive intestinal polypeptide (VIP) have been considered as important mediators in migraine and other primary headaches. plasma during attacks of migraine or cluster headache, and CGRP receptor antagonists have recently been shown to be effective in migraine therapy. Substance P and CGRP are produced from a subset of trigeminal afferents, whereas VIP derives from parasympathetic efferents. Release of these neuropeptides in the meninges can cause arterial vasodilatation, mast cell degranulation and plasma extravasation in animal experiments, but only CGRP seems to be relevant in migraine. Animal models have confirmed the important role of CGRP in meningeal nociception. The activity of spinal trigeminal neurons is a sensitive integrative measure of trigeminal activity and is partly under the control of CGRP, most likely via central mechanisms. CGRP released from central terminals of trigeminal afferents in the spinal trigeminal nucleus seems to facilitate nociceptive transmission via presynaptic mechanisms. The central effect of CGRP is substantiated by suppression of nociceptive c-fos activation and neuronal activity in the spinal trigeminal nucleus following CGRP receptor inhibition. These proposed functions are supported by the localization of CGRP receptor components in the rat cranial dura mater, trigeminal ganglion and spinal trigeminal nucleus. The currently available data indicate multiple sites of CGRP action in trigeminal nociception and the pathogenesis of migraine; however, central CGRP receptors are likely to be the essential targets in the treatment of migraine using CGRP receptor antagonists. (Keio J Med 60 (3) : 82-89,

Stable expression of G protein coupled receptors in cell lines is a crucial tool for the characterization of the molecular pharmacology of receptors and the screening for new antagonists. However, in some instances, many difficulties have been encountered to obtain stable cell lines expressing functional receptors. Here, we addressed the question of vector optimization to establish cell lines expressing the human neuropeptide Y receptor 5 (NPY5-R) or histamine receptor 4 (HH4R). We have compared bicistronic vectors containing viral or cellular Internal Ribosome Entry Sites (IRES), co-expressing the receptor and the neomycine resistance gene from a single mRNA, to a bigenic vector containing two distinct promoters upstream each different genes. This study is the first one to validate the use of three cellular IRESs for long term transgene expression. Our results demonstrate for both NPY5-R and HH4R that the bicistronic vectors with EMCV, VEGF, FGF1A or FGF2 IRES provide clones expressing functional receptors with yields between 25% and 100%. In contrast, the bigenic vector provided no functional clones, related to a low expression of NPY5R mRNA. The cell lines expressing active receptor were stable after more than 50 passages. These data indicate that IRES-based bicistronic vectors are particularly appropriate to establish cell clones expressing active G-coupled protein receptors with a high yield. In the case of NPY5, it was a new way to produce such a stable cell line. Furthermore, the characteristics -presented herein -of this receptor pharmacological property are perfectly in line with those reported in the literature.

Social play is a critical component of mammalian development, with disruptions linked to neurodevelopmental disorders such as autism spectrum disorder, ADHD, and schizophrenia. Arginine vasopressin (AVP), produced by magnocellular neurons of the hypothalamus, has been implicated in the regulation of social play, though its role appears context- and sex-dependent. This study investigated whether stimulation of AVP release through osmotic challenge influences juvenile social behavior. Male and female Long-Evans rats were administered intraperitoneal injections of hypertonic saline (1M or 3.5M), isotonic saline, or no injection prior to behavioral testing. Social play, huddling, aggression, and social approach were quantified in same-sex dyads. Results revealed that administration of 3.5M hypertonic saline significantly reduced play behavior and increased huddling, with no notable effects on aggression or social approach. Contrary to the initial hypothesis that AVP release would enhance play behavior, findings suggest that magnocellular AVP activity may exert inhibitory effects on play under osmotic stress. However, the observed increase in huddling and signs of sickness behavior raise the possibility that the effects reflect general malaise rather than AVP-specific mechanisms. These results highlight the complexity of AVP’s role in regulating juvenile social behaviors and underscore the need for refined experimental approaches that dissociate AVP’s behavioral effects from non-specific consequences of hyperosmolar challenge.

The social interaction test of anxiety was developed 25 years ago to provide an ethologically based test that was sensitive to both anxiolytic and anxiogenic effects. It is sensitive to a number of environmental and physiological factors that can affect anxiety. It has detected anxiogenic effects of peptides such as corticotropin-releasing factor (CRF) and adrenocorticotropic hormone (ACTH), and anxiolytic effects of neuropeptide Y and substance P receptor antagonists. It has successfully identified neuropharmacological sites of action of anxiogenic compounds and drug withdrawal. Effects of compounds acting on the g-aminobutyric acid (GABA) and 5-hydroxytryptamine (5-HT) systems have been extensively investigated after both systemic administration and microinjection into specific brain regions. The use of this test has, thus, played a crucial role in unravelling the neural basis of anxiety. It is hoped that in the next 25 years, the test will play a crucial role in determining the genetic basis of anxiety disorders.

Apoptosis of hypothalamic neurons is believed to play an important role in the development and perpetuation of obesity. Similar to the hippocampus, the hypothalamus presents constitutive and stimulated neurogenesis, suggesting that obesity-associated hypothalamic dysfunction can be repaired. Here, we explored the hypothesis that n-3 polyunsaturated fatty acids (PUFAs) induce hypothalamic neurogenesis. Both in the diet and injected directly into the hypothalamus, PUFAs were capable of increasing hypothalamic neurogenesis to levels similar or superior to the effect of brain-derived neurotrophic factor (BDNF). Most of the neurogenic activity induced by PUFAs resulted in increased numbers of proopiomelanocortin but not NPY neurons and was accompanied by increased expression of BDNF and G-protein–coupled receptor 40 (GPR40). The inhibition of GPR40 was capable of reducing the neurogenic effect of a PUFA, while the inhibition of BDNF resulted in the reduction of global hypothalamic cell. ...

During exocytosis, secretory granules fuse with the plasma membrane and discharge their content into the extracellular space. The exocytosed membrane is then reinternalized in a coordinated fashion. A role of clathrin-coated vesicles in this process is well established, whereas the involvement of a direct retrieval mechanism (often called kiss and run) is still debated. Here we report that a significant population of docked secretory granules in the neuroendocrine cell line PC12 fuses with the plasma membrane, takes up fluid-phase markers, and is retrieved at the same position. Fusion allows for complete discharge of small molecules, whereas GFP-labeled neuropeptide Y (molecular mass ≈35 kDa) is only partially released. Retrieved granules were preferentially associated with dynamin. Furthermore, recapture is inhibited by guanosine 5′-[γ-thio]triphosphate and peptides known to block dynamin function. We conclude that secretory granules can be recaptured immediately after formation of...

At advanced stages, Alzheimer's disease (AD) is characterized by an extensive neuronal loss. However, the early neurodegenerative deficiencies have not been yet identified. Here we report an extensive, selective and early neurodegeneration of the dendritic inhibitory interneurons (oriens-lacunosum moleculare, O-LM, and hilar perforant path-associated, HIPP, cells) in the hippocampus of a transgenic PS1 × APP AD model. At 6 months of age, from 22 different pre-and postsynaptic mRNA markers tested (including GABAergic, glutamatergic and cholinergic markers), only the expression of somatostatin (SOM) and NPY neuropeptides (O-LM and HIPP markers) displayed a significant decrease. Stereological cell counting demonstrated a profound diminution (50-60%) of SOM-immunopositive neurons, preceding the pyramidal cell loss in this AD model. SOM population co-expressing NPY was the most damaged cell subset. Furthermore, a linear correlation between SOM and/or NPY deficiency and Abeta content was also observed. Though the molecular mechanism of SOM neuronal loss remains to be determined, these findings might represent an early hippocampal neuropathology. Therefore, SOM and NPY neuropeptides could constitute important biomarkers to assess the efficacy of potential early AD treatments.

Neuropeptide Y (NPY), a powerful neurotransmitter of the central nervous system, is a key regulator of angiogenesis and biology of adipose depots. Intriguingly, its peripheral vascular and angiogenic powerful activity is strictly associated to platelets, which are source of clinical hemoderivates, such as platelet lysate (PL), routinely employed in several clinical applications as wound healing, and to preserve ex vivo the progenitor properties of the adipose stromal cells pool. So far, the presence of NPY in PL and its biological effects on the adipose stromal cell fraction (ASCs) have never been investigated. Here, we aimed to identify endogenous sources of NPY such as PL-based preparations and to investigate which biological properties PL-derived NPY is able to exert on ASCs. The results show that PL contains a high amount of NPY, which is in part also excreted by ASCs when stimulated with PL. The protein levels of the three main NPY subtype receptors (Y1, Y2, Y5) are unaltered b...

The pharmacological activity of neuropeptide Y (NPY) and some analogues in inhibiting the twitch contractions induced by electrical stimulation (single pulses at 25 V, 0.15 Hz, 1 ms) in the prostatic portion of the rat isolated vas deferens was investigated. The rank order of agonist potency was: PYY &gt; NPY2–36 &gt; NPY &gt;&gt; NPY13–36 &gt;&gt; NPY&gt;8–36 &gt;&gt;&gt; [Leu31, Pro34]NPY = hPP, which is consistent with the activation of a Y2 receptor. The putative Y1 and Y2 antagonist, benextramine (BXT), incubated at 100 μm for 10 or 60 min, was ineffective against PYY‐induced inhibition of the twitch response, suggesting that the prejunctional Y2 receptor in this tissue is different from the postjunctional one reported in the literature to be sensitive to BXT blockade. The putative NPY antagonist, PYX‐2, incubated at 1 μm for 20 min, was completely ineffective in antagonizing PYY‐induced inhibition of twitches. The twitch response was totally inhibited by suramin (100 μm) but w...

Background: It was recently reported that the mono-iodoacetate (MIA) experimental model of osteoarthritis (OA) courses with changes of neurons innervating the affected joints that are commonly interpreted as a neuronal response to axonal injury. To better characterize these changes, we evaluated the expression of two markers of neuronal damage, ATF-3 and NPY, and the growth associated protein GAP-43, in primary afferent neurons of OA animals injected with three different doses of MIA (0.3, 1 or 2 mg). Measurements were performed at days 3, 7, 14, 21 and 31 post-MIA injection. Results: OA animals showed the characteristic histopathological changes of the joints and the accompanying nociceptive behaviour, evaluated by the Knee-Bed and CatWalk tests. An increase of ATF-3 expression was detected in the DRG of OA animals as early as 3 days after the injection of 1 or 2 mg of MIA and 7 days after the injection of 0.3 mg. NPY expression was increased in animals injected with 1 or 2 mg of M...

Background. The management of pulmonary neuroendocrine tumours, with special reference to clinically aggressive carcinoids and large cell neuroendocrine carcinomas, is poorly standardized and data about somatostatin receptor expression or therapeutic guidelines for somatostatin analog administration are still debated. A series of 218 lung neuroendocrine tumours (24 metastatic typical carcinoids, 73 atypical carcinoids, 60 large cell neuroendocrine carcinomas and 61 surgically resected small cell carcinomas) was investigated for somatostatin receptor types 2A and 3 tissue distribution using immunohistochemistry, in correlation with clinicopathologic parameters, outcome, scintigraphy and treatment. Results. Somatostatin receptors were heterogeneously distributed with a significant progressive decrease from low to high grade forms. Somatostatin receptor type 2A was strikingly overexpressed in metastatic typical carcinoids as compared to atypical carcinoids and clinically benign typical carcinoids. Somatostatin receptor tissue immunolocalization correlated with octreotide scintigraphy in 20/28 cases. Conclusions. The immunohistochemical determination of somatostatin receptors, with special reference to low/intermediate grade tumors, may assist the clinical approach with somatostatin analog-based diagnostic and therapeutic procedures in clinically aggressive pulmonary neuroendocrine tumors.

None of the receptor ligands studied: the dopamine D2 antagonist eticlopride, D2/D3 antagonist haloperidol, alpha1-adrenergic antagonist prazosin, N-methyl-D-aspartate antagonist MK-801, 5-HT2/D2 antagonist mianserin, D2/D3 agonist quinpirole and alpha2-adrenergic agonist clonidine co-administrated with repeated amphetamine (AMPH) injections blocked the AMPH-induced decrease in the striatal and nucleus accumbens neuropeptide Y (NPY) levels. Only the D1/D5 receptor antagonist SCH 23390 insignificantly attenuated this effect what suggests that these dopamine receptor subtypes may partially mediate AMPH effect on NPY. Moreover, the results of multiple administrations of the receptor ligands to control rats indicate that the NPY systems in both structures under study are modulated in the same manner by dopaminergic activity and differentially by adrenergic, N-methyl-D-aspartate and serotonergic activity.

The effect of some agonists and antagonists of glutamatergic receptors (GluR) on neuropeptide Y (NPY) level in the rat hippocampus was investigated using radioimmunoassay method. The compounds were injected intraperitoneally (NMDA, ACPC and MPEP) or intrahippocampally (L-CCG, L-SOP, AIDA). It was found that NMDA induced a decrease in NPY-IR in the hippocampus. No significant changes were found after ACPC (a functional NMDA receptor antagonist) and MPEP (mGlu5 receptor antagonist). NPY-IR was significantly increased after intrahippocampal injections of group II and III mGluR agonists (L-CCG-I and L-SOP, respectively), as well as after group I mGluR antagonist AIDA. The obtained results indicate that glutamatergic metabotropic and NMDA receptors may regulate NPY expression in the hippocampus. This regulation may have some connection with modulation of anxiety by the studied compounds.

Repeated (+)-amphetamine sulfate (AMPH) administration (5 mg/kg sc twice daily for 6 days and once on day 7) markedly and reversibly decreased (until 96 h after the final dose) neuropeptide Y-like immunoreactivity (NPY-LI) in the rat striatum (caudate-putamen) and nucleus accumbens, and had no effect on NPY-LI in the hippocampus. No significant alterations were detected in the hybridization signal of NPY mRNA4 and 24 h after the end of AMPH treatment. A single dose of AMPH (5 mg/kg sc) administered to rats 4 and 24 h prior to sacrifice had no effect on NPY-LI in the brain structures studied. Moreover, AMPH injected 8 days after the last dose of repeated AMPH administration did not change NPY-LI up to 72 h. The minimal dose of haloperidol, the strong mixed dopaminergic D2/D1 receptor antagonist, (0.75 mg/kg injected ip 30 min before each of the multiple AMPH administrations) that was sufficient to completely block stereotypy and hyperlocomotion elicited by multiple AMPH administrations enhanced the AMPH-induced decrease in the striatal and accumbens NPY-LI. Our results suggest that NPY neurons in the striatum, nucleus accumbens and hippocampus are not directly involved in the acute behavioral response to AMPH (stereotypy and hyperlocomotion) as well as in the initiation and expression of AMPH-induced behavioral sensitization.

Neuropeptide Y (NPY) is known to play a role in the regulation of satiety, energy balance, body weight, and insulin release. Interleukin-1beta (IL1B) has been associated with loss of beta-cell mass in type-II diabetes (TIID). The present study attempts to investigate the association of NPY exon2 +1128 T/C (Leu7-Pro; rs16139), NPY promoter -399 T/C (rs16147) and IL1B -511 C/T (rs16944) polymorphisms with TIID and their correlation with plasma lipid levels, BMI, and IL1B transcript levels. PCR-RFLP was used for genotyping these polymorphisms in a case-control study involving 558 TIID patients and 1085 healthy age-matched controls from Gujarat. Linkage disequilibrium and haplotype analysis of the NPY polymorphic sites were performed to assess their association with TIID. IL1B transcript levels in PBMCs were also assessed in 108 controls and 101 patients using real-time PCR.

High intakes of multivitamins (HV) during pregnancy by Wistar rats increase food intake, body weight, and characteristics of the metabolic syndrome in male offspring. In this study, high-fat soluble vitamins were fed in combination during gestation to test the hypothesis that they partially account for the effects of the HV diet. Pregnant Wistar rats (14-16/group) were fed a recommended multivitamin diet (1-fold all vitamins) or high-fat soluble vitamin diet (HFS; 10-fold vitamins A, D, E, and K) during pregnancy. Offspring body weight, food intake, and preference as well as expression of selected genes in the hypothalamus and hippocampus were evaluated at birth, weaning, and 14 weeks postweaning. Body weight and food intake were not affected but sucrose preference decreased by 4% in those born to dams fed the HFS gestational diet. Gene expressions of the hypothalamic anorexogenic pro-opiomelanocortin (Pomc) and orexogenic neuropeptide Y (Npy) (∼30% p = 0.008, ∼40% p = 0.007) were i...

cause of metabolic syndrome, suggesting that some component(s) of the multivitamin preparation is impacting development of the feeding pathways in the brain. A possible explanation for altered development of intake regulatory systems resides in epigenetic mechanisms involving methyltransfer reactions. Because our recent data have demonstrated that the obesogenic phenotype of offspring of dams fed a HV diet is prevented by a post-weaning diet in either multivitamins or folate, 5 it can be suggested that folate alone within the multivitamin preparation is impacting the feeding neurocircuitry. Folate is a methyl metabolism co-factor in processes of DNA methylation, 6 which in turn can modify gene expression and function in regulatory systems. However, it is unknown whether folate alone in the HV gestational diet is responsible for the obesogenic phenotype in mature offspring, and whether folate in the pup diet can provide protection against these effects.

Catecholamines play an important regulatory role in cutaneous wound healing. The exact role of dopamine in human epidermis has yet to be fully elucidated. Current published evidence describes its differential effects on two separate families of G protein coupled receptors: D1-like and D2-like dopamine receptors. Dopamine may enhance angiogenesis and wound healing through its action on dopamine D1 receptors, while impairing wound healing when activating D2 receptors. This review summarizes the evidence for the role of dopamine in wound healing and describes potential mechanisms behind its action on D1 versus D2-like receptors in the skin.

Identification of the cellular players and molecular messengers that communicate neuronal activity to the vasculature driving cerebral hemodynamics is important for (1) the basic understanding of cerebrovascular regulation and (2) interpretation of functional Magnetic Resonance Imaging (fMRI) signals. Using a combination of optogenetic stimulation and 2-photon imaging in mice, we demonstrate that selective activation of cortical excitation and inhibition elicits distinct vascular responses and identify the vasoconstrictive mechanism as Neuropeptide Y (NPY) acting on Y1 receptors. The latter implies that task-related negative Blood Oxygenation Level Dependent (BOLD) fMRI signals in the cerebral cortex under normal physiological conditions may be mainly driven by the NPY-positive inhibitory neurons. Further, the NPY-Y1 pathway may offer a potential therapeutic target in cerebrovascular disease.

Kupffer cells (KC) and lipopolysaccharide (LPS) interaction is the initial event leading to hepatic inflammation and fibrosis in many types of liver injury. We studied chemokine secretion by KC activated with LPS and the possible effect of the somatostatin analogue octreotide, in the regulation of this process. 2 KC isolated from Sprague-Dawley rats were cultured in the presence of LPS added alone or with different concentrations of octreotide for 24 and 48 h, and chemokine production was assessed in culture supernatants by ELISA. CC chemokine mRNA expression was assessed by semiquantitative RT-PCR. 3 Vehicle-stimulated KC produced a basal amount of CC and CXC chemokines. LPS-stimulated KC secreted significantly increased amounts of IL-8 (GRO/CINC-1) (Po0.001), MIP-2 (Po0.001), MCP-1 (Po0.001), and RANTES (Po0.01). 4 Octreotide inhibited LPS-induced secretion of the CC chemokines MCP-1 (Po0.05) and RANTES (Po0.05), but not the CXC chemokines IL-8 (GRO/CINC-1) and MIP-2, in a concentration-dependent manner. Downregulation of basal and LPS-induced mRNA expression of the CC chemokines was also observed in the presence of octreotide. 5 Pretreatment with phosphatidylinositol 3 (PI3)-kinase inhibitors reduced chemokine production by LPS-treated KC in both the mRNA and protein level. Furthermore, it prevented the octreotide inhibitory effect on LPS-induced chemokine secretion, indicating a possible involvement of the PI3kinase pathway. 6 In conclusion, these data demonstrate that chemokine secretion by KC can be differentially regulated by octreotide, and suggest that this somatostatin analogue may have immunoregulatory effects on resident liver macrophages.

Background: Hypnoanesthesia is a state of anesthesia achieved through hypnosis techniques. Meanwhile, local anesthesia is anesthesia carried out by injecting local anesthetic drugs in or around the surgical site which causes temporary obstruction to the conduction of afferent impulses. Objective: This research was conducted to prove that there is no difference between hypnoanesthesia and local anesthesia in minor surgical procedures, with the indication of pain relief. Methods: The research subjects were patients with benign soft tissue tumors consisting of 40 people who were divided into 2 groups, namely treatment and control. Minor surgical procedures with hypnoanesthesia were performed in the treatment group, while in the control group, minor surgical procedures were performed with local anesthesia using 2% lidocaine. Pain is measured with FPS (Face Pain Scale) and monitored with a vital sign monitor. The intervention process was recorded with camcorder video. Changes in serum levels of excitatory neurotransmitters (Glutamic Acid and Substance P) and inhibitory (Beta Endorphin, Enkephalin, and Serotonin) before and after intervention were analyzed using ELISA (Enzym-Link Immunosorbent Assay) in both groups. Results: In the treatment group, it was discovered that patients did not feel pain after undergoing hypnoanesthesia intervention by providing suggestions for the relief of pain in the area where surgery would be performed. In the control group, patients also did not feel pain after local anesthetic intervention in the area to be operated on. However, the results of research and statistical tests showed that there was no significant difference in changes in Beta Endorphins, Enkephalin, and Serotonin as inhibitory neurotransmitters (p > 0.05) or Glutamic Acid and Substance P as excitatory neurotransmitters (p > 0.05) before and after the intervention in both groups of research subjects. Conclusion: the results of this study show that there is no significant difference between the treatment and control groups, they have equality in the final result, namely the relief of pain.

Sucrose-rich diets compared to starch-rich diets are known to stimulate overeating under chronic conditions. The present study in normal-weight rats established an acute "preload-to-test meal" paradigm for demonstrating sucrose-induced hyperphagia and investigating possible mechanisms that mediate this behavioral phenomenon. In this acute paradigm, the rats were first given a small (15 kcals) sucrose preload (30% sucrose) for 30 min compared to an equicaloric, starch preload (25% starch with 5% sucrose) and then allowed to freely consume a subsequent test meal of lab chow. The sucrose preload, when compared to a starch preload equal in energy density and palatability, consistently increased food intake in the subsequent test meal occurring between 60-120 min after the end of the preload. Measurements of hormones, metabolites and hypothalamic peptides immediately preceding this hyperphagia revealed marked differences between the sucrose vs starch groups that could contribute to the increase in food intake. Whereas the sucrose group compared to starch group immediately after the preload (at 10 min) had elevated levels of glucose in serum and cerebrospinal fluid (CSF) along with reduced expression of neuropeptide Y (NPY) and agouti-related protein (AgRP) in the arcuate nucleus (ARC), the subsequent effects (at 30-60 min) just preceding the test meal hyperphagia were the reverse. Along with lower levels of glucose, they included markedly elevated serum and CSF levels of corticosterone and mRNA levels of NPY and AgRP in the ARC. In addition to establishing an animal model for sucroseinduced hyperphagia, these results demonstrate peripheral and central mechanisms that may mediate this behavioral phenomenon.

While a high-fat diet when compared to low-fat diet is known to produce overeating and health complications, less is known about the effects produced by fat-rich diets differing in their specific composition of fat. This study examined the effects of a high-fat diet containing relatively high levels of saturated compared to unsaturated fatty acids (HiSat) to a high-fat diet with higher levels of unsaturated fatty acids (USat). A HiSat compared to USat meal caused rats to consume more calories in a subsequent chow test meal. The HiSat meal also increased circulating levels of triglycerides (TG) and expression of the orexigenic peptides, galanin (GAL) in the hypothalamic paraventricular nucleus (PVN) and orexin (OX) in the perifornical lateral hypothalamus (PFLH). A similar increase in TG levels and PVN GAL and PFLH OX was also seen in rats given chronic access to the HiSat compared to USat diet, while neuropeptide Y (NPY) and agouti-related protein (AgRP) in the arcuate nucleus showed decreased expression. The importance of TG in producing these changes was supported by the finding that the TG-lowering medication gemfibrozil as compared to vehicle, when peripherally administered before consumption of a HiSat meal, significantly decreased the expression of OX, while increasing the expression of NPY and AgRP. These findings substantiate the importance of the fat composition in a diet, indicating that those rich in saturated compared to unsaturated fatty acids may promote overeating by increasing circulating lipids and specific hypothalamic peptides, GAL and OX, known to preferentially stimulate the consumption of a fat-rich diet.

Obesity is a multifactorial disorder with high heritability (50-75%), which is probably higher in early-onset and severe cases. Although rare monogenic forms and several genes and regions of susceptibility, including copy number variants (CNVs), have been described, the genetic causes underlying the disease still remain largely unknown. We searched for rare CNVs (&gt;100kb in size, altering genes and present in &lt;1/2000 population controls) in 157 Spanish children with non-syndromic early-onset obesity (EOO: body mass index &gt;3 standard deviations above the mean at &lt;3 years of age) using SNP array molecular karyotypes. We then performed case control studies (480 EOO cases/480 non-obese controls) with the validated CNVs and rare sequence variants (RSVs) detected by targeted resequencing of selected CNV genes (n = 14), and also studied the inheritance patterns in available first-degree relatives. A higher burden of gain-type CNVs was detected in EOO cases versus controls (OR = ...

Neuropeptide Y (NPY) is expressed in the hypothalamus where it exerts orexigenic actions within the feeding control circuit. While NPY stimulates feeding in juvenile and adult animals, it is not known whether NPY influences food intake at earlier life stages. We investigated a role for NPY in regulating feeding at two stages of the life cycle of an amphibian, the Western spadefoot toad Spea hammondii. We administered NPY by intracerebroventricular (i.c.v.) injection to juvenile toads or prometamorphic tadpoles, and monitored locomotion, feeding behavior and/or food intake. Injection of NPY (20 or 200 ng/g BW) into juvenile toads decreased the latency to, and increased the number of strikes at prey, and the number of crickets eaten compared to uninjected or vehicle-injected controls. By contrast, injection of NPY (0.02-20 ng/g BW) into prometamorphic tadpoles caused a dose-dependent decrease in time spent foraging compared to controls. Blocking NPY signaling in the prometamorphic tadpole brain by i.c.v. injection of a general NPY receptor antagonist increased foraging, and partly blocked the action of exogenous NPY on foraging. Taken together, our findings show a developmental reversal in NPY actions on feeding in an amphibian, with the peptide having a characteristic orexigenic action in the juvenile toad, but an inhibitory action on foraging in the prometamorphic tadpole. The anorexigenic action of NPY in the tadpole correlates with a decrease in feeding that occurs at metamorphic climax when the tadpole's gut and cranium remodels for the transition to a carnivorous diet.

Anorexia nervosa (AN) is classically defined as a condition in which an abnormally low body weight is associated with an intense fear of gaining weight and distorted cognitions regarding weight, shape, and drive for thinness. This article reviews recent evidences from physiology, genetics, epigenetics, and brain imaging which allow to consider AN as an abnormality of reward pathways or an attempt to preserve mental homeostasis. Special emphasis is put on ghrelino-resistance and the importance of orexigenic peptides of the lateral hypothalamus, the gut microbiota and a dysimmune disorder of neuropeptide signaling. Physiological processes, secondary to underlying, and premorbid vulnerability factors-the "pondero-nutritional-feeding basements"-are also discussed.

The eects of NPY and related peptides were examined on basal contractile force and nervemediated inotropic responses to electrical ®eld stimulation of the guinea-pig isolated left atrium. 2 Electrical ®eld stimulus (EFS)-inotropic response curves were constructed by applying 1-64 trains of four ®eld pulses (200 Hz, 0.1 ms duration, 100 V) across isolated left atria (paced at 4 Hz, 2 ms, 1 ± 4 V) within the atrial refractory period. Curves were constructed in presence of vehicle, propranolol (1 mM) or atropine (1 mM) to determine appropriate stimulus conditions. 3 The eects of PYY (1 ± 10,000 nM), NPY (0.01 ± 10 mM), N-Ac-[Leu 28,31 ]NPY(24 ± 36) (N-A[L]NPY(24 ± 36); 0.01 ± 10 mM) and clonidine (0.1 ± 1000 nM) were examined on the positive and negative inotropic responses to EFS (eight trains, four pulses per refractory period). 4 NPY-related peptides had no eect on basal force of contraction nor on the inotropic concentration-response curves to bethanechol or isoprenaline. All three peptides inhibited vagallymediated negative inotropic responses; rank order of potency PYY4NPY5N-A[L]NPY(24 ± 36) was consistent with an action at prejunctional Y 2 -receptors. Clonidine concentration-dependently inhibited sympathetic inotropic responses. However, PYY, NPY and N-A[L]NPY(24 ± 36) failed to mediate any signi®cant inhibition of the positive inotropic response to EFS. 5 These data demonstrate that NPY is an eective inhibitor of vagal but not sympatheticallymediated inotropic responses in the guinea-pig isolated left atria. This may suggest that endogenously co-released NPY is important in mediating cross talk between eerent components of the autonomic nervous system modulating cardiac contractility, acting overall to sustain positive inotropic responses.

Background: Corticotropin-releasing factor overexpressing (CRF-OE) male mice showed an inhibited feeding response to a fast, and lower plasma acyl ghrelin and Fos expression in the arcuate nucleus compared to wild-type (WT) mice. We investigated whether hormones and hypothalamic feeding signals are impaired in CRF-OE mice and the influence of sex. Methods: Male and female CRF-OE mice and WT littermates (4-6 months old) fed ad libitum or overnight fasted were assessed for body, adrenal glands and perigonadal fat weights, food intake, plasma hormones, blood glucose, and mRNA hypothalamic signals. Results: Under fed conditions, compared to WT, CRF-OE mice have increased adrenal glands and perigonadal fat weight, plasma corticosterone, leptin and insulin, and hypothalamic leptin receptor and decreased plasma acyl ghrelin. Compared to male, female WT mice have lower body and perigonadal fat and plasma leptin but higher adrenal glands weights. CRF-OE mice lost these sex differences except for the adrenals. Male CRF-OE and WT mice did not differ in hypothalamic expression of neuropeptide Y (NPY) and proopiomelanocortin (POMC), while female CRF-OE compared to female WT and male CRF-OE had higher NPY mRNA levels. After fasting, female WT mice lost more body weight and ate more food than male WT, while CRF-OE mice had reduced body weight loss and inhibited food intake without sex difference. In male WT mice, fasting reduced plasma insulin and leptin and increased acyl ghrelin and corticosterone while female WT showed only a rise in corticosterone. In CRF-OE mice, fasting reduced insulin while leptin, acyl ghrelin and corticosterone were unchanged with no sex difference. Fasting blood glucose was higher in CRF-OE with female > male. In WT mice, fasting increased hypothalamic NPY expression in both sexes and decreased POMC only in males, while in CRF-OE mice, NPY did not change, and POMC decreased in males and increased in females. Conclusions: These data indicate that CRF-OE mice have abnormal basal and fasting circulating hormones and hypothalamic feeding-related signals. CRF-OE also abolishes the sex difference in body weight, abdominal fat, and fasting-induced feeding and changes in plasma levels of leptin and acyl ghrelin.

Previous studies have shown that infusion of a GABA A receptor antagonist, such as bicuculline (bic), into the ventral pallidum (VP) of rats elicits vigorous ingestion in sated subjects and abnormal pivoting movements. Here, we assessed if the ingestive effects generalize to the lateral preoptic area (LPO) and tested both effects for modulation by dopamine receptor signaling. Groups of rats received injections of the dopamine D2 receptor antagonist, haloperidol (hal), the D1 antagonist, SCH-23390 (SCH), or vehicle (veh) followed by infusions of bic or veh into the VP or LPO. Ingestion effects were not observed following LPO bic infusions. Compulsive ingestion associated with VP activation was attenuated by hal, but not SCH. VP bic-elicited pivoting was attenuated by neither hal, nor SCH.

Neuropeptides are subject of increased interest for their alleged role in various central nervous system processes. However, in vivo assessment of these compounds is complicated because of the generally low concentrations in the brain and the neuropeptides susceptibility to proteolytic degradation. This explains why so few microdialysis studies on neuropeptides have been published in the past. An additional problem is insufficient in vivo recovery of the neuropeptides when using microdialysis membranes. In this study we determined the recovery and dynamic behavior of several microdialysis membranes in vitro for three neuropeptides. For this purpose existing radio immuno assays (RIA) were optimized for Substance P (SP), vasopressin and corticotrophin releasing factor quantification in microdialysates. Finally, local potassium stimulation in freely moving rats was used to induce neurotransmitter release in order to assess the dynamic behavior of the membranes in vivo. Our results show...

Huntingtin-associated protein 1 (HAP1) is a determinant marker for the stigmoid body (STB), a neurocytoplasmic physiological inclusion. STB/HAP1 enriched areas in the brain/spinal cord are usually protected from neurodegenerative diseases, whereas the regions with tiny amounts or no STB/HAP1 are affected. In addition to the brain/spinal cord, HAP1 is highly expressed in the myenteric/submucosal plexuses of the enteric nervous system in the gastrointestinal tract. The tongue is attached to the pharynx by the hyoid bone as an extension of the gastrointestinal system. To date, the immunohistochemical distribution and neurochemical characterization of HAP1 have not been elucidated in the lingual ganglia. Using immunohistochemistry and light microscopy, our current study demonstrates the expression and immunohistochemical phenotype of HAP1 in the lingual ganglia of adult mice. We showed that HAP1 was profoundly distributed in the intralingual ganglion (ILG) and the ganglia near the root ...

The corticotropin-releasing hormone receptor 2 (CRHR2) gene encodes CRHR2, contributing to the hypothalamic–pituitary–adrenal stress response and to hyperglycemia and insulin resistance. CRHR2−/− mice are hypersensitive to stress, and the CRHR2 locus has been linked to type 2 diabetes and depression. While CRHR2 variants confer risk for mood disorders, MDD, and type 2 diabetes, they have not been investigated in familial T2D and MDD. In 212 Italian families with type 2 diabetes and depression, we tested 17 CRHR2 single nucleotide polymorphisms (SNPs), using two-point parametric-linkage and linkage-disequilibrium (i.e., association) analysis (models: dominant-complete-penetrance-D1, dominant-incomplete-penetrance-D2, recessive-complete-penetrance-R1, recessive-incomplete-penetrance-R2). We detected novel linkage/linkage-disequilibrium/association to/with depression (3 SNPs/D1, 2 SNPs/D2, 3 SNPs/R1, 3 SNPs/R2) and type 2 diabetes (3 SNPs/D1, 2 SNPs/D2, 2 SNPs/R1, 1 SNP/R2). All detect...

We have previously demonstrated that running-wheel access normalizes the food intake and body weight of Otsuka Long-Evens Tokushima Fatty (OLETF) rats. Following 6 wk of running-wheel access beginning at 8 wk of age, the body weight of OLETF rats remains reduced, demonstrating a lasting effect on their phenotype. In contrast, access to a high-fat diet exacerbates the hyperphagia and obesity of OLETF rats. To determine whether diet modulates the long-term effects of exercise, we examined the effects of high-fat diet on food intake and body weight in OLETF rats that had prior access to running wheels for 4 wk. We found that 4 wk of running exercise significantly decreased food intake and body weight of OLETF rats. Consistent with prior results, 4 wk of exercise also produced long-lasting effects on food intake and body weight in OLETF rats fed a regular chow. When running wheels were relocked, OLETF rats stabilized at lower levels of body weight than sedentary OLETF rats. However, access to a high-fat diet offset these effects. When OLETF rats were switched to a high-fat diet following wheel relocking, they significantly increased food intake and body weight, so that they reached levels similar to those of sedentary OLETF rats fed a high-fat diet. Gene expression determination of hypothalamic neuropeptides revealed changes that appeared to be appropriate responses to the effects of diet and running exercise. Together, these results demonstrate that high-fat diet modulates the long-lasting effects of exercise on food intake and body weight in OLETF rats.

Neuropeptide Y (NPY) and peptide YY (PYY) are regulatory peptides that have considerable sequence homology with pan- creatic polypeptide. Because (a) NPY has been shown to be colocalized with noradrenaline in peripheral as well as central catecholaminergic neurons, and (b) alpha2-adrenergic recep- tors of adipocytes play a major role in the regulation of lipoly- sis, we investigated the effect of NPY and PYY on isolated fat cells. In human fat cells NPY and PYY promoted a dose-depen- dent inhibition of lipolysis elicited by 2 jg/ml adenosine deam- inase (removal of adenosine) whatever the lipolytic index used (glycerol or nonesterified fatty acids). In dog fat cells NPY and PYY inhibited adenosine deaminase-, isoproterenoland for- skolin-induced lipolysis. In humans and dogs the effects of NPY or PYY were abolished by treatment of cells with Borde- tella pertussis toxin, clearly indicating the involvement of a Gi protein in the antilipolytic effects. This study indicates that, in addition to alpha2-adrenergic agonists, NPY and PYY are also involved in the regulation of lipolysis in human and dog adipose tissue as powerful antilipo- lytic agents. Further studies are needed to characterize the pharmacological nature of the receptor mediating the inhibi- tory effect of NPY and PYY in fat cells. (

Neuropeptide Y (NPY) and peptide YY (PYY) are regulatory peptides that have considerable sequence homology with pan- creatic polypeptide. Because (a) NPY has been shown to be colocalized with noradrenaline in peripheral as well as central catecholaminergic neurons, and (b) alpha2-adrenergic recep- tors of adipocytes play a major role in the regulation of lipoly- sis, we investigated the effect of NPY and PYY on isolated fat cells. In human fat cells NPY and PYY promoted a dose-depen- dent inhibition of lipolysis elicited by 2 jg/ml adenosine deam- inase (removal of adenosine) whatever the lipolytic index used (glycerol or nonesterified fatty acids). In dog fat cells NPY and PYY inhibited adenosine deaminase-, isoproterenoland for- skolin-induced lipolysis. In humans and dogs the effects of NPY or PYY were abolished by treatment of cells with Borde- tella pertussis toxin, clearly indicating the involvement of a Gi protein in the antilipolytic effects. This study indicates that, in addition to alpha2-adrenergic agonists, NPY and PYY are also involved in the regulation of lipolysis in human and dog adipose tissue as powerful antilipo- lytic agents. Further studies are needed to characterize the pharmacological nature of the receptor mediating the inhibi- tory effect of NPY and PYY in fat cells. (