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Kisspeptins have emerged as potent elicitors of gonadotropin secretion and, therefore, putative targets for pharmacological intervention. In this context, desensitization of gonadotropin responses to continuous administration of kisspeptins has begun to be characterized, but information so far available is mostly restricted to LH responses in males, whereas the similar phenomenon in females, of obvious therapeutic interest, remains virtually unexplored. We report herein LH and FSH responses to continuous intracerebral administration of kisspeptin in female rats at different developmental and metabolic states. Infusion of kisspeptin-10 to adult female rats induced a transient elevation in serum LH concentrations, followed by a precipitous drop and normalization of LH levels thereafter. Elevation of LH after kisspeptin infusion was prolonged in underfed animals; a phenomenon mimicked by leptin administration. Conversely, FSH levels were persistently heightened along continuous kisspeptin infusion, but duration of this response was shortened by undernutrition. In pubertal females, LH and FSH levels remained elevated at the end of a 7-day infusion of kisspeptin; responses whose magnitude was augmented by subnutrition but not mimicked by leptin. In all settings, terminal gonadotropin-releasing hormone responses were fully preserved, suggesting that eventual desensitization must occur upstream from the pituitary. In summary, our current data document the pharmacological consequences of continuous administration of kisspeptin to female rats, with remarkable differences being detected between LH and FSH responses, in different developmental and metabolic states. These observations of potential pharmacological interest might help also to delineate the physiological roles of kisspeptins in the dynamic regulation of gonadotropin secretion in the female. KiSS-1; G protein-coupled receptor 54; gonadotropin-releasing hormone; constant infusion; fasting; leptin; puberty; luteinizing hormone; follicle-stimulating hormone doi: 10.1152/ajpendo.90240.2008.

Reproductive function is exquisitely sensitive to adequacy of nutrition and fuel reserves, through mechanisms that are yet to be completely elucidated. Galanin-like peptide (GALP) has recently emerged as another neuropeptide link that couples reproduction and metabolism. However, although the effects of GALP on luteinizing hormone (LH) secretion have been studied, no systematic investigation on how these responses might differ along sexual maturation and between sexes has been reported. Moreover, the influence of metabolic status and potential interplay with other relevant neurotransmitters controlling LH secretion remain ill defined. These facets of GALP physiology were addressed herein. Intracerebral injection of GALP to male rats induced a dose-dependent increase in serum LH levels, the magnitude of which was significantly greater in pubertal than in adult males. In contrast, negligible LH responses to GALP were detected in pubertal or adult female rats at diestrus. Neonatal androgen treatment to females failed to 'masculinize' the pattern of LH response to GALP. In addition, metabolic stress by short-term tasting did not prevent but rather amplified LH responses to GALP in pubertal males, whereas these responses were abrogated by pharmacological inhibition of nitric oxide synthesis. We conclude that the ability of GALP to evoke LH secretion is sexually differentiated, with maximal responses at male puberty, a phenomenon which was not reverted by manipulation of sex steroid milieu during the critical neonatal period and was sensitive to metabolic stress. This state of LH hyperresponsiveness may prove relevant for the mechanisms relaying metabolic status to the reproductive axis in male puberty. gonadotropin-releasing hormone; kisspeptin; hypothalamus

Development and normal function of the reproductive axis requires a precise degree of body energy stores. Polypeptide YY-(3-36) [PYY-(3-36)] is a gastrointestinal secreted molecule recently shown to be involved in the control of food intake with agonistic activity on neuropeptide Y (NPY) receptor subtypes [Y.sup.2] and [Y.sub.5]. Notably, PYY-(3-36) has been recently demonstrated as putative regulator of gonadotropin secretion in the rat. However, the 'reproductive' facet of this factor remains to be fully elucidated, In this context, we report herein our analyses of the influence of the nutritional status on the effects of PYY-(3-36) upon GnRH and gonadotropin secretion. The major findings of our study are 1) the stimulatory effect of central administration of PYY-(3-36) on LH secretion was significantly enhanced after fasting and blocked by a GnRH antagonist: 2) besides central effects, PYY-(3-36) elicited LH and FSH secretion directly at the pituitary level, a response that is also augmented by fasting; 3) PYY-(3-36) inhibited GnRH secretion by hypothalamic fragments from male rats fed ad libitum, whereas a significant stimulatory effect was observed after fasting; and 4) the increase in the gonadotropin responsiveness to PYY-(3-36) in fasting was not associated with changes in the expression of [Y.sub.2] and [Y.sub.5] receptor genes at hypothalamus and/or pituitary. In conclusion, our study extends our previous observations suggesting a relevant, mostly stimulatory, role of PYY-(3-36) in the control of gonadotropin secretion. Strikingly, such an effect was significantly enhanced by fasting. Considering the proposed decrease in PYY-(3-36) levels after fasting, the possibility that reduced PYY-(3-36) secretion might contribute to defective function of the gonadotropic axis after food deprivation merits further investigation. polypeptide YY-(3-36); gonadotropin-releasing hormone; luteinizing hormone; follicle-stimulating hormone; fasting; pituitary

The human genome contains nearly 100 deubiquitinating enzymes (DUBs) responsible for removing ubiquitin moieties from a large variety of substrates. Which DUBs are responsible for targeting which substrates remain mostly unknown. Here we implement the bio Ub approach to identify DUB substrates in a systematic manner, combining gene silencing and proteomics analyses. Silencing of individual DUB enzymes is used to reduce their ubiquitin deconjugating activity, leading to an increase of the ubiquitination of their substrates, which can then be isolated and identified. We report here quantitative proteomic data of the putative substrates of 5 human DUBs. Furthermore, we have built a novel interactive database of DUB substrates to provide easy access to our data and collect DUB proteome data from other groups as a reference resource in the DUB substrates research field.

Mutations in genes encoding subunits of the SWI/SNF chromatin remodeling complex are frequently found in different human cancers. While the tumor suppressor function of this complex is widely established in solid tumors, its role in hematologic malignancies is largely unknown. Recurrent point mutations in BCL7A gene, encoding a subunit of the SWI/SNF complex, have been reported in diffuse large B-cell lymphoma (DLBCL), but their functional impact remains to be elucidated. Here we show that BCL7A often undergoes biallelic inactivation, including a previously unnoticed mutational hotspot in the splice donor site of intron one. The splice site mutations render a truncated BCL7A protein, lacking a portion of the amino-terminal domain. Moreover, restoration of wild-type BCL7A expression elicits a tumor suppressor-like phenotype in vitro and in vivo. In contrast, splice site mutations block the tumor suppressor function of BCL7A by preventing its binding to the SWI/SNF complex. We also show that BCL7A restoration induces transcriptomic changes in genes involved in B-cell activation. In addition, we report that SWI/SNF complex subunits harbor mutations in more than half of patients with germinal center B-cell (GCB)-DLBCL. Overall, this work demonstrates the tumor suppressor function of BCL7A in DLBCL, and highlights that the SWI/SNF complex plays a relevant role in DLBCL pathogenesis.

We have examined divergence times of the Antillean damselfly genus Hypolestes, to elucidate which mechanism of allopatric speciation, vicariance or long-distance dispersal, could better explain the currently observed disjunct distributions of this genus. Samples of the three extant species of the genus, Hypolestes clara (Jamaica), H. hatuey (Hispaniola) and H. trinitatis (Cuba), were collected. Mitochondrial and nuclear DNA gene fragments were amplified to reconstruct phylogenetic relationships and estimate divergence times in this genus. Hypolestes comprises currently three species, which consist in four geographically and genetically isolated lineages located in Jamaica, Hispaniola, Eastern Cuba and Central Cuba. Results of our analyses suggest that the three species diverged between ∼5.91 and 1.69 mya, and that the separation between the lineages from Central Cuba and Eastern Cuba occurred between ∼2.0 and 0.62 mya. Disjunct distributions in the genus Hypolestes can be better explained by a long-distance dispersal mechanism, since the divergence times of the three species do not coincide with the timeline formation of the geographic barriers between Cuba, Hispaniola and Jamaica. The Cuban lineages of H. trinitatis constitute different molecular operational taxonomic units (MOTU). The elevation of these MOTU to the species category requires the analysis of additional characters., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Lumbricidae taxonomy is vastly restricted by the morphological simplicity of earthworms and their lack of complex appendices. This has led to confusing results in the Lumbricidae classifications, which in turn, has hindered our ability to identify and assign new and cryptic species to the family. Here we propose the addition of a new Lumbricidae genus from the Zagros and Elburz Mountains of Iran, i.e. Philomontanus gen. nov, including three new species. Our taxonomic inferences were based on the phylogenetic analysis of two nuclear gene regions (28S rDNA and 18S rDNA) and 11 mitochondrial gene regions (16S rDNA, 12S rDNA, NADH dehydrogenase I, cytochrome oxidase subunits I and II and tRNAs Asn, Asp, Val, Leu, Ala and Ser). Philomontanus gen. nov comprises the earthworm species Philomontanus sarii sp. nov., Philomontanus mahmoudi sp. nov. and Philomontanus baloutchi sp. nov. These three species are morphologically similar to each other with only a few characters separating them (e.g. size, pigmentation and position of clitellum). Our findings support the adoption of an integrative approach including molecular information (e.g., DNA sequences) to aid earthworm classification and develop a robust taxonomy., Competing Interests: The authors have declared that no competing interests exist.

Objective: The present work proposes the shark teeth as a new source of bioapatites for bone filler applications in maxillary sinus elevation, periodontal regeneration or implants placement. This abundant fishing by-product provides an improved hydroxyapatite (HA) with fluorine contributions. The in vivo evaluation of osteointegration and bone mineral density levels promoted by these marine bioapatites was the main objective., Materials and Methods: Marine bioapatite granules of two sizes (1 mm, <20 μm) were obtained and characterized (XRD, SEM, ICP-OES) to determine morphology and composition. In vivo evaluation was performed, after bioapatites implantation in critical defects of parietal bone of 25 rats, for 3 weeks. Commercial synthetic HA/βTCP (60/40%) material and unfilled defects were used as controls. Radiology, micro-CT, histology and quantification of bone mineral density are presented., Results: These marine bioapatites presented a globular porous morphology. A biphasic composition ~70% apatitic (HA, apatite-CaF, fluorapatite) and ~30% non-apatitic phase (whitlockite, tricalcium bis(orthophosphate)), with contributions of F (1.0 ± 0.5%wt), Na (0.9 ± 0.2%wt) and Mg (0.65 ± 0.04%wt) was confirmed. After implantation period, higher osteointegration of 1-mm marine bioapatites than commercial synthetic granules was observed, together with bone formation from the defect surroundings but also at central area (potential osteoinductive properties). New bone cells penetrated inside pores and inter-granular cavities. Higher bone mineral density, in both 1-mm and <20-μm granules, than on commercial synthetic graft was determined, being significant in 1-mm bioapatites (a P < 0.05)., Conclusion: Shark teeth bioapatites were successfully validated as new functionally efficient bone filler in rat model, promoting significantly increased bone mineral density than synthetic control., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Tissue membranes are boundaries that isolate organs or cavities in the body. These semi-permeable membranes are responsible for passive protection that acts through the regulation of nutrient absorption, secretion and filtration of small molecules. These functions could be altered as a consequence of inflammation or trauma, which in turn could lead to changes in permeability, allowing the entrance of toxins, antigens, proteins or facilitating the spread of tumors. Membrane permeability therefore plays an important role in numerous diseases. However, current experimental techniques that are available to quantify membrane permeability in small animals have limited precision and temporal specificity. Improvements in such measurements would lead to a deeper understanding of disease pathogenesis and this may accelerate the development of specific therapies. The study reported here concerns the efficacy of a novel, non-invasive imaging analysis-based measurement method that significantly improves the quantification of tissue membrane permeability in small animals, while at the same time mitigating the adverse effects experienced by the animals under study.

Control of estrous cycle and reproductive capacity involves a large number of central and peripheral factors, integrating numerous nutritional and metabolic signals. Here we show that glucagon-like peptide-1 (GLP-1), a peptide with anorexigenic and insulinotropic actions, and the GLP-1 receptor agonist Exendin-4 (Ex4) exert a regulatory influence on the gonadal axis, in both adult and prepubertal female rats. In adult rats, Glp-1 receptor expression varies during the estrous cycle at the hypothalamus, pituitary, and ovary. Furthermore, acute treatment with GLP-1 in the morning proestrus doubled the amplitude of the preovulatory LH surge, as well as influencing estradiol and progesterone levels along the estrous cycle. These changes provoked an important increase in the number of Graafian follicles and corpora lutea, as well as in the litter size. Conversely, Ex4 diminished the levels of LH, later producing a partial blockade at the preovulatory surge, yet not affecting either the number of mature follicles or corpora lutea. Chronic administration of low doses of GLP-1 to prepubertal rats synchronized vaginal opening and increased LH levels on the 35th day of life, yet at these doses it did not modify their body weight, food intake, or ovarian and uterine weight. By contrast, chronic exposure to Ex4 produced a significant reduction in ovarian and uterine weight, and serum LH, and the animals treated chronically with Ex4 showed no vaginal opening in the period studied. Overall, our results demonstrate that GLP-1 and Ex4 act on the gonadal axis, involving the hypothalamic kisspeptin system, to influence reproductive efficiency in female rats.

Diabetes alters microvascular function in the vascular beds of organs, including the lungs. Cardiovascular complications of pulmonary vascular affectation may be a consequence of the overactivation of the vasoconstrictive and proliferative components of the renin-angiotensin system. We previously reported that pulmonary physiology and surfactant production is improved by the glucagon-like peptide 1 receptor (GLP-1R) agonist liraglutide (LIR) in a rat model of lung hypoplasia. Because we hypothesized that streptozotocin-induced diabetes rats would show deficiencies in lung function, including surfactant proteins, and develop an imbalance of the renin-angiotensin system in the lungs. This effect would in turn be prevented by long-acting agonists of the GLP-1R, such as LIR. The induction of diabetes reduced the surfactant protein A and B in the lungs and caused the vasoconstrictor component of the renin-angiotensin system to predominate, which in turn increased angiotensin II levels, and ultimately being associated with right ventricle hypertrophy. LIR restored surfactant protein levels and reversed the imbalance in the renin-angiotensin system in this type 1 diabetes mellitus rat model. Moreover, LIR provoked a strong increase in angiotensin-converting enzyme 2 expression in the lungs of both diabetic and control rats, and in the circulating angiotensin(1-7) in diabetic animals. These effects prompted complete reversion of right ventricle hypertrophy. The consequences of LIR administration were independent of glycemic control and of glucocorticoids, and they involved NK2 homeobox 1 signaling. This study demonstrates by first time that GLP-1R agonists, such as LIR, might improve the cardiopulmonary complications associated with diabetes.

Glucagon-like peptide-1 (GLP-1) and the GLP-1 receptor agonist, exendin-4 (Ex-4), potently stimulate hypothalamic-pituitary-adrenal (HPA) axis activity after either central or peripheral administration. Because several GLP-1 derivative drugs, including synthetic Ex-4, are currently in use to treat patients with type II diabetes mellitus, the characterization of Ex-4 effects on the HPA axis is highly relevant. Herein, the roles of CRH and AVP on these effects were investigated by administering the antagonists astressin and d(CH2)5Tyr(Me)AVP, respectively. The role of the sympathoadrenal system (SAS) was explored in bilateral adrenal enucleated and guanethidine-treated rats, whereas primary pituitary cell cultures were used to study direct effects on the corticotropes. Astressin completely abrogated (P < .05) the effects of Ex-4 central administration on ACTH secretion but only slightly reduced (by 35%) the ACTH response to Ex-4 peripheral administration. Moreover, astressin significantly (P < .05) decreased the corticosterone response to centrally but not peripherally administered Ex-4, suggesting different mechanisms depending on the route of administration. Pretreatment with d(CH2)5Tyr(Me)AVP failed to diminish either the ACTH or corticosterone response to Ex-4 and no direct effect of Ex-4 or GLP-1 was observed on pituitary cell cultures. In contrast, a significant (P < .05) reduction in the corticosterone response elicited by Ex-4 peripheral administration was observed in enucleated and guanethidine-treated rats, indicating a role of the SAS in the glucocorticoid stimulatory effects of Ex-4. Our data demonstrate that the effects of Ex-4 on the HPA axis are partially mediated by CRH and the sympathoadrenal system, and stress the relevance of Ex-4 as a corticosterone secretagogue.

Exendin-4 (Ex-4) is a natural agonist of the glucagon-like peptide-1 (GLP-1) receptor, currently being used as a treatment for type 2 diabetes mellitus due to its insulinotropic properties. Previous studies have revealed that acute administration of both GLP-1 and, in particular, Ex-4 potently stimulates hypothalamic-pituitary-adrenal (HPA) axis activity. In this work, the effects of prolonged Ex-4 exposure on HPA function were explored. To this end, Sprague-Dawley rats were subjected to a daily regimen of two Ex-4 injections (5 μg/kg sc) for a minimum of 7 days. We found that subchronic Ex-4 administration produced a number of effects that resemble chronic stress situations, including hyperactivation of the HPA axis during the trough hours, disruption of glucocorticoid circadian secretion, hypertrophy of the adrenal gland, decreased adrenal gland sensitivity, impaired pituitary-adrenal stress responses, and reductions in both food intake and body weight. In addition, a threefold increase in diuresis was observed followed by a 1.5-fold increase in water intake; these latter effects were abolished by adrenalectomy. Together, these findings indicate that Ex-4 induces a profound dysregulation of HPA axis activity that may also affect renal function.

The glucagon-like peptide-1 receptor (GLP-1R) is found in a variety of tissues outside of the pancreas. For example, GLP-1R is expressed in the lung, where it has been implicated in the regulation of the lipid fraction of surfactants, suggesting it fulfills an important role in lung function. Here, we show that GLP-1R expression is strongly up-regulated immediately after birth in neonatal rats, particular in male offspring. Moreover, administering long half-life GLP-1R agonists to the mother from gestational day 14 to birth (exendin-4 or liraglutide) increased surfactant protein (SP)-A and SP-B mRNA expression and the amount of SPs in the amniotic fluid at the end of pregnancy. These effects were similar or more potent to those induced by the glucocorticoid dexamethasone, which also increased GLP-1R expression in fetuses just before delivery. Lir increased fetal SP-A and GLP-1R expression in control rats and in a nitrofen-induced model of lung hypoplasia. Moreover, lung size increased in controls after Lir administration, which also prevented the decrease in lung weight and the poor neonatal survival of the offspring from nitrofen-treated dams, effects that were not produced by dexamethasone. Taken together, our results demonstrate the importance of the GLP-1 system in regulating SP production and lung development.

Purpose: This case demonstrates the use of carotid stents in off-label emergency condition where standard self-expandable stents doesn't fit to native artery and balloon-expandable stents could not be also recommended., Case Report: 56 years old patient, EVAR therapy performed 2 months before, suffering acute severe abdominal pain; emergency angioCT showed oclusion of superior mesenteric artery (SMA) and no complications related to previous EVAR. A percutaneuos supraselective trombolysis was performed. After 24 hours control DSA showed partial recanalization and tight stenoses in distal SMA with poor run-off to terminal branches. A 6-8 x 40 mm Carotid Stent (Acculink®, Abbot Vascular) was implanted with good inmediate technical result. After 6 months follow up both SMA and branches remain patent and no further treatment was required., Conclusions: tapered self expandable uncovered stents are a good treatment option to achieve better conformability to SMA,and bare metal stents do not compromise side-branches of this artery.

A method for the measurement of the phase and group velocities of guided acoustic waves is presented. For this purpose, a unique capability of a self-developed double-pulsed TV holography system to create movies of the propagation of guided acoustic wavetrains is used. Thereby, the experimental visualization of the evolution of Lamb and Rayleigh wavetrains in aluminum plates is shown, including several movies that illustrate different dispersive behaviors. Each movie shows the propagation of a narrowband wavetrain with a central frequency in the order of 1 MHz that consists of a carrier moving with the phase velocity, modulated by an envelope moving with the group velocity. Each snapshot is a two-dimensional map of the instantaneous out-of-plane displacement field of the surface points of the plate, with amplitudes in the order of several nanometers, acquired with the double-pulsed TV holography system. Then, by repeating the acquisition with successively increasing delays between the generation and detection instants, a sequence of maps is obtained from which a movie is composed. The phase and group velocities of the waves are accurately measured from the movies, yielding values that match well with the reference values for the same plates obtained from independent measurements.

S-adenosylhomocysteine (SAH), the metabolic precursor of homocysteine in the body, is a potent inhibitor of methylation reactions. Several methylation reactions play a major role in epigenetic regulation of protein expression, atherosclerosis, and cancer development. Here we studied the mechanisms responsible for the maintenance of circulating SAH levels by measurement of the arterio-venous differences across the kidney, splanchnic organs, and the lung in humans. The lungs did not remove or add any circulating SAH, whereas the liver released it into the hepatic veins. The kidney extracted 40% of SAH and the SAH arterio-venous difference across the kidney was directly and significantly related to its arterial levels. Thus, the kidney plays a major role in maintaining SAH levels and may, indirectly, control tissue transmethylation reactions. Our findings of a pivotal role for the human kidney in sulfur amino acid metabolism may also account for the increased plasma levels of SAH in patients with chronic kidney diseases.

Renal synthesis and excretion of ammonia are critical for efficient removal of acids from the body. Besides the rate of ammonia production, the intrarenal distribution of produced ammonia is a crucial step in the renal regulation of acid-base balance. Various acid-base disorders are associated not only with changes in ammonia production but also with its distribution between the urine and the renal veins. The final effect of ammonia production on acid-base balance largely depends on the events that determine the distribution of ammonia produced between urine and blood. Several factors, among which urine pH, urine flow, total ammonia production "per se" and renal blood flow may affect the percent of ammonia excreted into urines in humans with different acid-base disturbances. Among these factors, urine pH is the most important. An additional effect of stimulated ammoniagenesis is kidney hypertrophy. In tubule epithelial cells, the associated increase in ammonia production, rather than the acidosis per se, is responsible for favoring tubular hypertrophy. This effect is related to the inhibition of protein degradation, owing to changes in lysosomal pH and cathepsin activity, without effects on cell cycle. Both changes of PI-3 kinase pathway and the suppression of chaperone-mediated autophagy are candidate mechanism for ammonia-mediated inhibition of protein degradation in tubule cells. Available data in humans indicate that the response of kidney to metabolic acidosis includes both changes in amino acid uptake and suppression of protein degradation. The latter effect is associated with the increase in ammonia excretion and partition into the urine.

Resistance to the anabolic action of growth hormone may contribute to the loss of strength and muscle mass in adult patients with chronic kidney disease. We tested this hypothesis by infusing growth hormone in patients to levels necessary to saturate hormone receptors. This led to a significant decrease of plasma potassium and amino acid levels in control and hyperkalemic patients with chronic kidney disease. These effects were completely or partially blunted in patients with elevated C-reactive protein levels. In forearm perfusion studies, growth hormone caused a further decrease in the negative potassium and protein balance of hemodialysis patients without inflammation but no effect was seen in patients with inflammation. Only IL-6 levels and age were found to be independent correlates in these growth hormone-induced variations in plasma potassium and blood amino acids. This shows that although a resistance to pharmacologic doses of growth hormone is not a general feature of patients with chronic kidney disease, there is a subgroup characterized by blunted growth hormone action. Our results support the hypothesis that uremia with inflammation, but not uremia per se, inhibits downstream growth hormone signaling contributing to muscle atrophy.