Hypothalamic Levels Research Articles

Changes of plasma concentration and gene expression of ghrelin and leptin in rats receiving kisspeptin and morphine.

Kisspeptin is a hypothalamic peptide which stimulates hypothalamus- pituitary- gonadal (HPG) axis. Morphine is an alkaloid which suppresses reproduction. Ghrelin and leptin are metabolic peptides which play role in relaying information to the HPG axis. In the present study, the interaction effects of kisspeptin and morphine were investigated on plasma and gene expression levels of leptin and ghrelin. Twenty adult male Wistar rats randomized in four groups were received injection of saline, kisspeptin (1.00 nmol), morphine (5.00 mg kg-1) or Kisspeptin + morphine. Rats were received kisspeptin and morphine via third cerebral ventricular and subcutaneous injection, respectively. Ten male rats in two groups were received intravenous injection of saline or kisspeptin (7.50 nmol). Blood samples, hypothalamic and adipose tissue samples were collected. Plasma and gene expression levels of ghrelin and leptin were measured using the methods of enzyme-linked immunosorbent assay and real time-PCR, respectively. Morphine significantly increased plasma concentration and hypothalamic mRNA levels of ghrelin compared to saline while kisspeptin significantly decreased them compared to saline. Morphine significantly decreased plasma and mRNA levels of leptin in adipose tissue compared to saline, however, kisspeptin did not increase plasma and mRNA levels of leptin in adipose tissue compared to saline. Kisspeptin significantly decreased the effects of morphine on plasma concentration and hypothalamic gene expression levels of ghrelin compared to morphine alone, however, it did not affect morphine influence on plasma and leptin gene expression levels compared to morphine alone. Kisspeptin and morphine might partly be involved in the regulation of reproductive activity via regulation the metabolic hormones synthesis.

Cloning and expression of kiss genes and regulation of feeding in Siberian sturgeon (Acipenser baerii).

In 1996, kiss was reported to regulate feeding in mammals, but studies are limited in fish. Our study aimed to explore the possible role of kiss in the regulation of feeding in Siberian sturgeon (Acipenser baerii). kiss1 and kiss2 were cloned, and the expression patterns were analyzed in Siberian sturgeon. The complete coding regions of kiss1 and kiss2 genes were 393 and 471bp. Both kiss1 and kiss2 showed the highest expression level in the hypothalamus. During the periprandial and fasting experiments, the expression of kiss1 and kiss2 highly significantly increased in the hypothalamus after feeding (P < 0.01). Compared with the feeding group, in hypothalamus, kiss1 expression in the fasting group highly significantly decreased (P < 0.01). In contrast, kiss2 expression had no significant difference on days 1 and 7 (P > 0.05) but highly significantly increased on day 14 (P < 0.01). Subsequently, the feeding function was verified by intraperitoneal (i.p.) injection of Kp1(10) and Kp1(10) into fish. The resultsshowed that i.p. injection of 1µg/g BW Kp1(10) or 0.01µg/g BW Kp2(10) could significantly reduce 0-1h food intake (P < 0.05) and affected the expression levels of apelin, ghrelin, leptin, nmu, etc. in the hypothalamus. Theseresultssuggested that kiss1 plays an anorexic role in both short- and long-term feeding regulation, while kiss2 plays a short-term anorexic and long-term orexigenic role. This study described kiss as a novel regulator of appetite in fish and laid the groundwork for further studies focused on physiological function. HIGHLIGHTS: • The kiss1 and kiss2 of Siberian sturgeon were cloned. • The expression levels of kiss1 and kiss2 mRNA were the highest in the hypothalamus. • Postprandial hypothalamic kiss1 and kiss2 expression levels increased in the periprandial experiment. • In the fasting test, the expression of hypothalamic kiss1 decreased after fasting, while the expression of kiss2 increased after fasting on the 14th day. • Siberian sturgeon food intake was reduced, and appetite factors expression levels in the hypothalamus were altered after intraperitoneal injection of Kp1(10) and Kp2(10).

Effect of rapid eye movement sleep deprivation during pregnancy on glucocorticoid receptor regulation of HPA axis function in female offspring

Poor maternal sleep quality during the different phases of pregnancy acts as a prenatal stress and is critical for fetal development. Despite the potential adverse effects of maternal stress on the behavior and physiology of the offspring, the mechanisms remain poorly understood. The present study investigates the effects of maternal sleep deprivation (SD) at different stages of pregnancy on the hypothalamic–pituitary–adrenal (HPA) axis in female offspring. The pregnant rats were subjected to sleep deprivation of 12 h per day at different stages; early (ESD), mid (MSD), and late (LSD) stages, on pregnancy days 1–7, 8–14, and 14–20, respectively. At postnatal day 60, levels of corticosterone (CORT), hypothalamic corticotropin-releasing factor receptor 1 (CRF-R1), and hippocampal glucocorticoid receptors (GR) were evaluated in the offspring. Although the hypothalamic CRF-R1 level was increased in the offspring of SD dams, immunohistochemical staining showed reduced immunoreactivity of GR in ESD and LSD offspring hippocampal area. Altogether, the data suggests that a critical period for adverse effects of SD on the HPA axis in female offspring of Wistar rats may be during early and late pregnancy.

Effects of saturated versus unsaturated fatty acids on metabolism, gliosis, and hypothalamic leptin sensitivity in male mice

ABSTRACT Background Development of obesity and its comorbidities is not only the result of excess energy intake, but also of dietary composition. Understanding how hypothalamic metabolic circuits interpret nutritional signals is fundamental to advance towards effective dietary interventions. Objective We aimed to determine the metabolic response to diets enriched in specific fatty acids. Methods Male mice received a diet enriched in unsaturated fatty acids (UOLF) or saturated fatty acids (SOLF) for 8 weeks. Results UOLF and SOLF mice gained more weight and adiposity, but with no difference between these two groups. Circulating leptin levels increased on both fatty acid-enriched diet, but were higher in UOLF mice, as were leptin mRNA levels in visceral adipose tissue. In contrast, serum non-esterified fatty acid levels only rose in SOLF mice. Hypothalamic mRNA levels of NPY decreased and of POMC increased in both UOLF and SOLF mice, but only SOLF mice showed signs of hypothalamic astrogliosis and affectation of central fatty acid metabolism. Exogenous leptin activated STAT3 in the hypothalamus of all groups, but the activation of AKT and mTOR and the decrease in AMPK activation in observed in controls and UOLF mice was not found in SOLF mice. Conclusions Diets rich in fatty acids increase body weight and adiposity even if energy intake is not increased, while increased intake of saturated and unsaturated fatty acids differentially modify metabolic parameters that could underlie more long-term comorbidities. Thus, more understanding of how specific nutrients affect metabolism, weight gain, and obesity associated complications is necessary.

Does Sertraline Affect Hypothalamic Food Intake Peptides in the Rat Experimental Model of Chronic Mild Stress-Induced Depression?

Depression is a chronic, recurrent and life-threatening disease affecting approximately 15% of the world population. Depression is responsible for neuropathologies like decreased neurogenesis and increased dendritic atrophy. Antidepressant treatments increase hippocampal neurogenesis and neurotrophic factor expression. Based on this information, it was aimed to investigate effect of sertraline on depression in rats with chronic mild stress (CMS) model and to determine how it affects cell proliferation and hypothalamic peptide levels in hypothalamus. 56 adult male Wistar albino; control, depression(D), depression + sertraline, sertraline were divided into groups. Various stressors were applied to D for 30days. Open field test (OFT) and forced swimming test (FST) were conducted to check whether the animals were depressed. On the 16th day osmotic minipump was placed subcutaneously and sertraline (10mg/kg/day) was administered for 15days. Behavior tests were done. Hypothalamic peptide gene expression levels were analyzed by quantitative RT-PCR. Statistical evaluations were made using ANOVA. It caused a decrease in the percentage of movement in the D and control groups in the OFT, an increase in the immobility time in the D group in the FST, and an increase in the swimming behavior in the DS group. Animals did not show any anxiological behavior based on the elevated plus maze test results. CMS caused a decrease in GLUT2 and NPY gene expression in the hypothalamus of animals, an increase in POMC and FGFR2, and an increase in IGFIR and GLUT2 gene expression in the DS group. Sertraline has been shown to ameliorate the effects of CMS-induced depression. Sertraline is thought to have a positive regulatory effect on both the formation of neural precursor cells and the survival of newly formed neurons in the hypothalamus. Newly formed neurons in the hypothalamus express food intake-related NPY, POMC, GLUT2 neurons, and thus hypothalamic tanycytes may play a key role in the control of energy metabolism.

Hypothalamic expression of huntingtin causes distinct metabolic changes in Huntington's disease mice

ObjectiveIn Huntington's disease (HD), the disease-causing huntingtin (HTT) protein is ubiquitously expressed and causes both central and peripheral pathology. In clinical HD, a higher body mass index has been associated with slower disease progression, indicating the role of metabolic changes in disease pathogenesis. Underlying mechanisms of metabolic changes in HD remain poorly understood, but recent studies suggest the involvement of hypothalamic dysfunction. The present study aimed to investigate whether modulation of hypothalamic HTT levels would affect metabolic phenotype and disease features in HD using mouse models. MethodsWe used the R6/2 and BACHD mouse models that express different lengths of mutant HTT to develop lean- and obese phenotypes, respectively. We utilized adeno-associated viral vectors to overexpress either mutant or wild-type HTT in the hypothalamus of R6/2, BACHD, and their wild-type littermates. The metabolic phenotype was assessed by body weight measurements over time and body composition analysis using dual-energy x-ray absorptiometry at the endpoint. R6/2 mice were further characterized using behavioral analyses, including rotarod, nesting-, and hindlimb clasping tests during early- and late-time points of disease progression. Finally, gene expression analysis was performed in R6/2 mice and wild-type littermates in order to assess transcriptional changes in the hypothalamus and adipose tissue. ResultsHypothalamic overexpression of mutant HTT induced significant gender-affected body weight gain in all models, including wild-type mice. In R6/2 females, early weight gain shifted to weight loss during the corresponding late stage of disease despite increased fat accumulation. Body weight changes were accompanied by behavioral alterations. During the period of early weight gain, R6/2 mice displayed a comparable locomotor capacity to wild-type mice. When assessing behavior just prior to weight loss onset in R6/2 mice, decreased locomotor performance was observed in R6/2 females with hypothalamic overexpression of mutant HTT. Transcriptional downregulation of beta-3 adrenergic receptor (B3AR), adipose triglyceride lipase (ATGL), and peroxisome proliferator-activated receptor-gamma (PPARγ) in gonadal white adipose tissue was accompanied by distinct alterations in hypothalamic gene expression profiles in R6/2 females after mutant HTT overexpression. No significant effect on metabolic phenotype in R6/2 was seen in response to wild-type HTT overexpression. ConclusionsTaken together, our findings provide further support for the role of HTT in metabolic control via hypothalamic neurocircuits. Understanding the specific central neurocircuits and their peripheral link underlying metabolic imbalance in HD may open up avenues for novel therapeutic interventions.

Интраназально вводимый инсулин, но не С-пептид проинсулина, нормализует гормональные показатели и экспрессию гипоталамических генов у самцов крыс с диабетом 2-го типа и ожирением

Type 2 diabetes mellitus (DM2) is characterised by changes in brain signalling systems, including those regulated by insulin. Intranasally administered insulin (II) can be used to restore brain insulin signalling. The effectiveness of II, as we have shown earlier in DM1 and insulin-deficient DM2, increases when combined with intranasally administered C-peptide (IC). The aim of this work was to study the effect of a 9-day treatment of rats with diet-induced DM2, obesity and hyperinsulinemia with II (0.5 IU/rat/day) and combined II and IC (36 μg/rat/day) on rats’ metabolic parameters, basal and glucose-stimulated levels of insulin, adipokines, glucagon-like peptide-1 and ghrelin, hormonal status of the thyroid and gonadal systems, intrahypothalamic insulin and leptin levels, and expression of hypothalamic genes encoding receptors and nutritional factors. II monotherapy normalised hypothalamic insulin levels lowered in DM2, improved glucose homeostasis, thyroid status and insulin, leptin and incretin responses to glucose, restored the expression of hypothalamic proopiomelanocortin and M4-melanocortin receptor genes responsible for reducing appetite, and reduced the gene expression of orexigenic neuropeptide Y. The combined use of II and IC did not improve the effect of II. IC monotherapy was ineffective and even worsened subject metabolic parameters. Thus, in DM2 rats with hyperinsulinemia, II improved metabolic and hormonal parameters. This is due to normalisation of the brain insulin levels that had been reduced as a result of weaker receptor-mediated transport of insulin across the blood-brain barrier. IC, however, was ineffective, including in combination with II.

The activation of hypothalamic AMP-activated protein kinase by oxidative stress is related to hyperphagia in diabetic rats.

During diabetes, there are increased blood glucose levels and oxidative stress. The relationship between oxidative stress and the phosphorylation of AMP-activated protein kinase at the hypothalamic level has been little studied. The objective of this study was to analyze the relationship between oxidative stress and AMP-activated protein kinase activation in Wistar rats with hyperphagia and hyperglycemia. Rats at 7, 14, and 28 days with diabetes were used. Control rats were included. Food intake was calculated to determine hyperphagia. The hypothalamus was extracted to evaluate oxidative stress markers by spectrophotometry; phosphorylation of AMP-activated protein kinase, growth hormone receptor 1a, and neuropeptide Y expression were determined by Western blot. There was a significant increase in the consumption of food in the experimental groups. The level of malondialdehyde decreased in the 7-day group (33%) and increased significantly in the 28-day group (90%), glutathione peroxidase activity increased in the 7-day group (70%) and decreased in the 28-day group (34%), and the phosphorylation of AMP-activated protein kinase increased significantly in the 28-day group (86%). Under ex-vivo conditions in animals with 28 days of hyperglycemia, glutathione peroxidase activity increased 195%, the malondialdehyde level decreased 87%, phosphorylation of AMP-activated protein kinase decreased 53%, and growth hormone receptor 1a expression decreased 66%, when treating hyperglycemic hypothalamic tissue with an antioxidant. NPY expression increased in hyperglycemia, and antioxidant treatment did not regulate its expression. The activation of AMP-activated protein kinase is related with an increase in oxidative stress markers in hyperglycemic and hyperphagic rats.

Growth hormone receptor contributes to the activation of STAT5 in the hypothalamus of pregnant mice

Growth hormone (GH) receptor (GHR) signaling induces the phosphorylation of the signal transducer and activator of transcription 5 (pSTAT5) in the cells of several tissues including in the hypothalamus. During pregnancy, several STAT5-recruiting hormones (e.g., prolactin, GH and placental lactogens) are highly secreted. However, the precise contribution of GHR signaling to the surge of pSTAT5 immunoreactive neurons that occurs in the hypothalamus of pregnant mice is currently unknown. Thus, the objective of the present study was to determine whether GHR expression in neurons is required for inducing pSTAT5 expression in several hypothalamic nuclei during pregnancy. Initially, we demonstrated that late pregnant C57BL/6 mice (gestational day 14 to 18) exhibited increased pulsatile GH secretion compared to virgin females. Next, we confirmed that neuron-specific GHR ablation robustly reduces hypothalamic Ghr mRNA levels and prevents GH-induced pSTAT5 in the arcuate, paraventricular and ventromedial hypothalamic nuclei. Subsequently, the number of pSTAT5 immunoreactive cells was determined in the hypothalamus of late pregnant mice. Although neuron-specific GHR ablation did not affect the number of pSTAT5 immunoreactive cells in the paraventricular nucleus of the hypothalamus, reduced pSTAT5 expression was observed in the arcuate and ventromedial nuclei of pregnant neuron-specific GHR knockouts, compared to control pregnant mice. In summary, a subset of hypothalamic neurons requires GHR signaling to express pSTAT5 during pregnancy. These findings contribute to the understanding of the endocrine factors that affect the activation of transcription factors in the brain during pregnancy.

Acute Effect of Caffeine on the Synthesis of Pro-Inflammatory Cytokines in the Hypothalamus and Choroid Plexus during Endotoxin-Induced Inflammation in a Female Sheep Model.

This study was designed to determine the effect of acute caffeine (CAF) administration, which exerts a broad spectrum of anti-inflammatory activity, on the synthesis of pro-inflammatory cytokines and their receptors in the hypothalamus and choroid plexus (ChP) during acute inflammation caused by the injection of bacterial endotoxin—lipopolysaccharide (LPS). The experiment was performed on 24 female sheep randomly divided into four groups: control; LPS treated (iv.; 400 ng/kg of body mass (bm.)); CAF treated (iv.; 30 mg/kg of bm.); and LPS and CAF treated. The animals were euthanized 3 h after the treatment. It was found that acute administration of CAF suppressed the synthesis of interleukin (IL-1β) and tumor necrosis factor (TNF)α, but did not influence IL-6, in the hypothalamus during LPS-induced inflammation. The injection of CAF reduced the LPS-induced expression of TNF mRNA in the ChP. CAF lowered the gene expression of IL-6 cytokine family signal transducer (IL6ST) and TNF receptor superfamily member 1A (TNFRSF1) in the hypothalamus and IL-1 type II receptor (IL1R2) in the ChP. Our study on the sheep model suggests that CAF may attenuate the inflammatory response at the hypothalamic level and partly influence the inflammatory signal generated by the ChP cells. This suggests the potential of CAF to suppress neuroinflammatory processes induced by peripheral immune/inflammatory challenges.

A Single Dose of Ginkgo biloba Extract Induces Gene Expression of Hypothalamic Anorexigenic Effectors in Male Rats

Previous studies have shown that Ginkgo biloba extract (GbE) reduces food intake and body mass gain and regulates proteins related to lipid metabolism in obese rats. In ovariectomized rats, GbE restored the hippocampal and hypothalamic serotonergic system activity, favoring the spontaneous feeding decrement. Considering the promising hypophagic effect of GbE, this study aimed to investigate the effect of a single acute dose on hypothalamic pathways that regulate feeding behavior in male rats. Four-month-old Wistar male rats received either a single acute oral GbE dose (500 mg/kg) or vehicle. Food intake and body mass were measured after 1, 4, 12, and 24 h. Rats were euthanized, and hypothalami were removed for mRNA quantification of anorexigenic (POMC/CART) and orexigenic (AgRP/NPY) neuropeptides, leptin/serotonin receptors (5HT1A, 5HT1B, 5HT2C), and serotonin transporters. We also investigated POMC, 5-HT1B, and 5-HT2C protein levels. A single acute GbE dose induced the hypothalamic POMC, CART, and 5-HT2C gene expression but failed to modify orexigenic effectors. No alterations in food intake, body mass, and hypothalamic protein levels were observed. In summary, the present findings demonstrate the rapid stimulation of pivotal hypothalamic anorexigenic pathways in response to a single GbE administration, reinforcing the GbE hypophagic activity. However, more studies are necessary to evaluate its potential as an appetite modulator.

Voluntary exercise could reduce sperm malformations by improving hypothalamus-hypophysis-gonadal axis and kisspeptin/leptin signaling in type 2 diabetic rats.

Objective(s):Most male patients with type 2 diabetes mellitus (T2DM) experience infertility. It is well established that regular physical activity could alleviate diabetic infertility symptoms. This study was designed to determine the effect of voluntary exercise on sperm malformation. Materials and Methods:Thirty-two male Wistar rats were randomly divided into control (C), diabetic (D), voluntary exercise (Ex), and diabetic-voluntary exercise (D-Ex) groups. Diabetes was induced by an intraperitoneal injection of streptozotocin (35 mg/kg) followed by a high-fat diet for four weeks. Voluntary exercise was performed by placing the animals in the rotary wheel cages for ten weeks. Sperm malformations were analyzed. Moreover, the hypothalamic leptin, kisspeptin, kisspeptin receptors (KissR), as well as plasma LH, FSH, testosterone, and leptin levels were evaluated. Results:Results showed that induction of T2DM caused increased sperm malformation, plasma, and hypothalamic leptin as well as decreased hypothalamic kisspeptin, KissR, and plasma LH levels compared with the C group (P<0.001 to P<0.01). Voluntary exercise in the Ex group increased hypothalamic KissR, plasma FSH, LH, and testosterone levels compared with the C group; however, it decreased sperm malformation and hypothalamic leptin levels (P<0.001 to P<0.05). Voluntary exercise in the D-Ex group reduced sperm malformation, hypothalamic leptin, and plasma testosterone while elevated hypothalamic kisspeptin and KissR protein levels compared with the D group (P<0.001 to P<0.01). Conclusion:The results illustrated voluntary exercise reduces sperm malformations by improving the HHG axis and kisspeptin/leptin signaling in rats with T2DM.

Dysfunction of the hypothalamic‑pituitary‑adrenal axis in male rat offspring with prenatal food restriction: Fetal programming of hypothalamic hyperexcitability and poor hippocampal feedback.

Prenatal food restriction (PFR) induces dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis in the adult offspring. The aim of the present study was to identify the underlying mechanism of this process. Pregnant rats were placed on a restricted diet between gestational day 11 and 21. The offspring were fed with a high-fat diet and were subjected to unpredictable chronic stress (UCS) from postnatal week 17 to 20. A higher serum corticosterone (CORT) level was observed in the PFR fetuses. Although lower arginine vasopressin (AVP), hippocampal vesicular glutamate transporter 2 (vGLUT2) and glutamic acid decarboxylase 65 (GAD65) mRNA expression levels were detected in the hippocampi of PFR fetuses, the ratio of the mRNA expression levels of vGLUT2 and GAD65 was higher compared with that of the controls, which was accompanied by histopathological and ultrastructural abnormalities of both the hypothalamus and hippocampus. However, there were no marked changes in the hippocampal expression levels of glucocorticoids receptor (GR) and mineralocorticoids receptor (MR) or the ratio of MR/GR ratio. After the fetuses had matured, lower serum CORT and adrenocorticotropic hormone (ACTH) levels were observed in PFR rats without UCS when compared with the control. A higher rise rate of serum ACTH was also observed after UCS when compared with that in rats without UCS. Furthermore, the hypothalamic mRNA expression level of corticotrophin-releasing hormone (CRH) was lower in PFR rats without UCS, while expression levels of CRH, AVP, GAD65 and vGLUT2 were enhanced after UCS when compared with the control, accompanied by an increased vGLUT2/GAD65 expression ratio. MR mRNA expression was lower, and GR mRNA expression was higher in the hippocampus of the PFR rats without UCS when compared with the control. However, the mRNA expression levels of both MR and GR in the PFR rats were higher compared with those of the control after UCS, which was accompanied histopathological changes in the dentate gyrus, cornu ammonis (CA1) and CA3 areas. In summary, it was suggested that PFR induced fetal alterations of the HPA axis manifesting as hypothalamic hyperexcitability and poor hippocampal feedback, which persisted to adulthood and affected the behavior of the rat offspring.

Mechanisms Driving Palmitate-Mediated Neuronal Dysregulation in the Hypothalamus.

The hypothalamus maintains whole-body homeostasis by integrating information from circulating hormones, nutrients and signaling molecules. Distinct neuronal subpopulations that express and secrete unique neuropeptides execute the individual functions of the hypothalamus, including, but not limited to, the regulation of energy homeostasis, reproduction and circadian rhythms. Alterations at the hypothalamic level can lead to a myriad of diseases, such as type 2 diabetes mellitus, obesity, and infertility. The excessive consumption of saturated fatty acids can induce neuroinflammation, endoplasmic reticulum stress, and resistance to peripheral signals, ultimately leading to hyperphagia, obesity, impaired reproductive function and disturbed circadian rhythms. This review focuses on the how the changes in the underlying molecular mechanisms caused by palmitate exposure, the most commonly consumed saturated fatty acid, and the potential involvement of microRNAs, a class of non-coding RNA molecules that regulate gene expression post-transcriptionally, can result in detrimental alterations in protein expression and content. Studying the involvement of microRNAs in hypothalamic function holds immense potential, as these molecular markers are quickly proving to be valuable tools in the diagnosis and treatment of metabolic disease.

Intranasal Carbetocin Reduces Hyperphagia and Anxiety and Distress Behaviors in Prader-Willi Syndrome: Results From the CARE-PWS Randomized, Double-Blind, Placebo-Controlled Study

Prader-Willi syndrome (PWS) is a complex genetic disorder associated with multiple neuroendocrine abnormalities, including significantly decreased hypothalamic oxytocin levels, resulting in symptoms of severe hyperphagia (an unrelenting false sense of starvation) and multiple severe neuropsychiatric and behavioral issues. CARE-PWS, a multi-center, randomized, double-blind, placebo-controlled phase 3 study, has evaluated the efficacy, safety and tolerability of intranasal carbetocin, a selective oxytocin receptor agonist, in participants with PWS. Eligible participants aged 7 through 18 with genetically confirmed PWS were randomized in equal proportions to three treatment arms for the 8-week placebo-controlled period of the study: carbetocin 9.6 mg, carbetocin 3.2 mg, or a matching placebo, administered by nasal spray three times a day with meals. The primary endpoint assessed changes from baseline to week 8 in Hyperphagia Questionnaire for Clinical Trials (HQ-CT) or Children’s Yale-Brown Obsessive Compulsive Scale (CY-BOCS) scores for the carbetocin 9.6 mg arm vs placebo, and the first secondary endpoint assessed changes from baseline to week 8 in HQ-CT or CY-BOCS scores for the carbetocin 3.2 mg arm vs placebo. Additional secondary endpoints included changes from baseline to week 8 in PWS Anxiety and Distress Questionnaire (PADQ) scores, and Clinical Global Impression of Change (CGI-C) scores evaluating the overall change in severity of PWS symptoms at week 8. Due to COVID-19, enrollment was closed early with 119 evaluable participants for the primary analysis. In the carbetocin 9.6 mg arm, trends toward numerically greater improvements in HQ-CT and CGI-C scores relative to placebo were observed but did not reach statistical significance; however, the carbetocin 3.2 mg arm demonstrated a significant improvement in HQ-CT scores (LS mean improvement vs placebo -3.14 points, p=0.016). In the 3.2 mg arm, additional consistent evidence of improvements versus placebo was seen in multiple secondary endpoints, including CGI-C (p=0.027) and PADQ (p=0.027). Numeric trends toward improvement in CY-BOCS scores were observed in each dose arm, but did not reach statistical significance versus placebo. During the subsequent long-term follow-up period of the study, both carbetocin arms have experienced continued numeric improvements from baseline across multiple endpoints. Intranasal carbetocin was generally well-tolerated; the most frequently reported adverse event was flushing, which was generally mild and transient. In conclusion, results of the CARE-PWS study support that intranasal carbetocin appears to be safe and well tolerated, and reduces hyperphagia and anxiety and distress behaviors in PWS.

Melanin-concentrating hormone neurons affect adipose tissues and modulate weight gain.

Melanin-concentrating hormone neurons affect adipose tissues and modulate weight gain.

Parental high-fat high-sugar diet programming and hypothalamus adipose tissue axis in male Wistar rats.

Maternal nutrition during early development and paternal nutrition pre-conception can programme offspring health status. Hypothalamus adipose axis is a target of developmental programming, and paternal and maternal high-fat, high-sugar diet (HFS) may be an important factor that predisposes offspring to develop obesity later in life. This study aims to investigate Wistar rats' maternal and paternal HFS differential contribution on the development, adiposity, and hypothalamic inflammation in male offspring from weaning until adulthood. Male progenitors were fed a control diet (CD) or HFS for 10weeks before mating. After mating, dams were fed CD or HFS only during pregnancy and lactation. Forming the following male offspring groups: CD-maternal and paternal CD; MH-maternal HFS and paternal CD; PH-maternal CD and paternal HFS; PMH-maternal and paternal HFS. After weaning, male offspring were fed CD until adulthood. Maternal HFS diet increased weight, visceral adiposity, and serum total cholesterol levels, and decreased hypothalamic weight in weanling male rats. In adult male offspring, maternal HFS increased weight, glucose levels, and hypothalamic NFκBp65. Paternal HFS diet lowered hypothalamic insulin receptor levels in weanling offspring and glucose and insulin levels in adult offspring. The combined effects of maternal and paternal HFS diets increased triacylglycerol, leptin levels, and hypothalamic inflammation in weanling rats, and increased visceral adiposity in adulthood. Male offspring intake of CD diet after weaning reversed part of the effects of parental HFS diet during the perinatal period. However, maternal and paternal HFS diet affected adiposity and hypothalamic inflammation, which remained until adulthood.

Photoperiod is involved in the regulation of seasonal breeding in male water voles (Arvicola terrestris).

Mammals living at temperate latitudes typically display annual cyclicity in their reproductive activity: births are synchronized when environmental conditions are most favorable. In a majority of these species, day length is the main proximate factor used to anticipate seasonal changes and to adapt physiology. The brain integrates this photoperiodic signal through key hypothalamic structures, which regulate the reproductive axis. In this context, our study aimed to characterize regulations that occur along the hypothalamo-pituitary-gonadal (HPG) axis in male fossorial water voles (Arvicola terrestris, also known as Arvicola amphibius) throughout the year and to further probe the implication of photoperiod in these seasonal regulations. Our monthly field monitoring showed dramatic seasonal changes in the morphology and activity of reproductive organs, as well as in the androgen-dependent lateral scent glands. Moreover, our data uncovered seasonal variations at the hypothalamic level. During the breeding season, kisspeptin expression in the arcuate nucleus (ARC) decreases, while RFRP3 expression in the dorsomedial hypothalamic nucleus (DMH) increases. Our follow-up laboratory study revealed activation of the reproductive axis and confirmed a decrease in kisspeptin expression in males exposed to a long photoperiod (summer condition) compared with those maintained under a short photoperiod (winter condition) that retain all features reminiscent of sexual inhibition. Altogether, our study characterizes neuroendocrine and anatomical markers of seasonal reproductive rhythmicity in male water voles and further suggests that these seasonal changes are strongly impacted by photoperiod.

Characterization of the Kisspeptin and GnRH expression in the hypothalamus of the male and female taiep rat, an animal model of demyelination.

Reproductive alterations have been reported in patients with demyelinating diseases, these alterations can lead to infertility. In the hypothalamus we can find two neuronal types that regulate reproductive function; kisspeptidergic and GnHergic neurons. At the present moment, the relation between demyelination and reproductive alterations it is yet unknown; in order to elucidate this relation, we used the taiep rat, an animal that presents demyelination of the central nervous system and that also shows reproductive issues. We characterized the immunofluorescent expression of kisspeptin and GnRH in the hypothalamus of the male and female taiep rats using Sprague-Dawley rats as control. We obtained the brains of the females during oestrous and adult males; the brains were cut at 10mm. Performed immunofluorescence of kisspeptin and GnRH (bs-0749r-cy5, bs-10369R-A488; Bioss Antibodies) and analysed the intensity of the fluorescence in the hypothalamus using the software ImageJ1.50i. Fluorescence is concentrated in fiber-like structures with neuron shape. An increment in the intensity of the fluorescence of kisspeptin was observed in said structures in male taiep rats compared with SD (0.37±0.02 vs 0.28±0.01, p< 0.001). Female taiep rats during oestrus showed a decrease in the intensity of the fluorescence of kisspeptin structures compared with SD (0.44±0.02 vs 0.57±0.03, p< 0.001). We could not observe any significant changes in the expression of GnRH fibers in the hypothalamus of the taiep rat compared with SD. Demyelination in the taiep rat affects kisspeptin expression at hypothalamic level, but this does not affect the expression of GnRH in either males or females, this effect is probably related with the availability of receptors in the GnRHergic neuron, we will evaluate this in the future. The decrease in kisspeptin expression in the female taiep rat, could be caused by previously reported low concentrations of oestrogen, given that it is capable of stimulating kisspeptin expression.

Nesfatin-1 stimulates the hypothalamus-pituitary-interrenal axis hormones in goldfish

Stress in vertebrates is mediated by the hypothalamus-pituitary-adrenal (in mammals)/interrenal (in fish) (HPA/I) axis, which produces the corticotropin-releasing factor (CRF), adrenocorticotropic hormone (ACTH), and corticosteroids, respectively. Nesfatin-1, a novel anorexigenic peptide encoded in the precursor nucleobindin-2 (NUCB2), is increasingly acknowledged as a peptide that influences the stress axis in mammals. The primary aim of this study was to characterize the putative effects of nesfatin-1 on the fish HPI axis, using goldfish (Carassius auratus) as an animal model. Our results demonstrated that nucb2/nesfatin-1 transcript abundance was detected in the HPI tissues of goldfish, with most abundant expression in the pituitary. NUCB2/nesfatin-1-like immunoreactivity was found in the goldfish hypothalamus, pituitary, and interrenal cells of the head kidney. GPCR12, a putative receptor for nesfatin-1, was also detected in the pituitary and interrenal cells. NUCB2/nesfatin-1-like immunoreactivity was observed in ACTH-expressing pituitary corticotrophs. Acute netting and restraint stress upregulated nucb2/nesfatin-1 mRNA levels in the forebrain, hypothalamus, and pituitary, as well as crf and crf-r1 expression in the forebrain and hypothalamus. Intraperitoneal and intracerebroventricular administration of nesfatin-1 increased cortisol release and hypothalamic crf mRNA levels, respectively. Finally, we found that nesfatin-1 significantly stimulated ACTH secretion from dispersed pituitary cells in vitro. Collectively, our data provide the first evidence showing that nesfatin-1 is a stress responsive peptide, which modulates the stress axis hormones in fish.