Neuropeptides in the rat claustrum - An immunohistochemical detection.

Neuropeptides are involved in numerous brain activities and are responsible for a wide spectrum of higher mental functions. The main purpose of this outline structural qualitative study was to identify the possible immunoreactivity of classical neuropeptides, as well as novel ones such as nesfatin-1, phoenixin (PNX), spexin (SPX), neuromedin U (NMU) and respective receptors within the rat claustrum for the first time. The study shows the novel identification of peptidergic neurotransmission in the rat claustrum which potentially implicates a contribution of this neuropeptide to numerous central neurosecretory mechanisms.

Spexin and nesfatin-1-expressing neurons in the male human claustrum.

Neuropeptides are involved in numerous brain activities being responsible for a wide spectrum of higher mental functions. The purpose of this concise, structural and qualitative investigation was to map the possible immunoreactivity of the novel regulatory peptides: spexin (SPX) and nesfatin-1 within the human claustrum. SPX is a newly identified peptide, a natural ligand for the galanin receptors (GALR) 2/3, with no molecular structure similarities to currently known regulatory factors. SPX seems to have multiple physiological functions, with an involvement in reproduction and food-intake regulation recently revealed in animal studies. Nesfatin-1, a second pleiotropic neuropeptide, which is a derivative of the nucleobindin-2 (NUCB-2) protein, is characterized by a wide distribution in the brain. Nesfatin-1 is a substance with a strong anorexigenic effect, playing an important role in the neuronal circuits of the hypothalamus that regulate food intake and energy homeostasis. On the other hand, nesfatin-1 may be involved in several important brain functions such as sleep, reproductive behaviour, cognitive processes, stress responses and anxiety. For the first time we detected and described a population of nesfatin-1 and SPX expressing neurons in the human claustrum using immunohistochemical and fluorescent methods. The study presents the novel identification of SPX and nesfatin-1 immunopositive neurons in the human claustrum and their assemblies show similar patterns of distribution in the whole structure.

Modulatory effect of olanzapine on neuronal nitric oxide synthase (nNOS) expression in the rat striatum.

Nitric oxide (NO) has been thought to be a novel factor involved in the mechanisms of mental disorders pathogenesis for quite some time. However, little is known about potential crosstalk between neuronal NO signaling and neuroleptics action. The present work was, therefore, focused on gene expression of neuronal NO synthase (nNOS) in the brains of rats chronically treated with olanzapine, an atypical antipsychotic drug. Studies were carried out on adult, male Sprague-Dawley rats that were divided into 2 groups: control and experimental animals treated with olanzapine (28-day-long intraperitoneal injection, at dose 5 mg/kg daily). All individuals were killed under anesthesia and the whole brains excised. Immunohistochemical procedure was used for histological assessment of the whole brain, and for both descriptive and quantitative analysis of nNOS protein distribution in selected brain structures. Long-term treatment with olanzapine is reflected in different changes in the number of enzyme-expressing cells in the rat brain. Olanzapine decreased the number of nNOS-expressing cells and possibly reduced NO synthesis in the rat striatum. Olanzapine can be taken into account as a potential inhibitor of NO synthesis in the rat striatum.

Olanzapine alters the expression of gasotransmitter-related enzymes: CBS and HO-2 in the rat hippocampus and striatum.

BACKGROUND: Gaseous neurotransmitters have been thought to be novel factors involved in the mechanisms of mental disorders pathogenesis for quite some time. However, little is known about the potential crosstalk between neuronal gasotransmitter signaling and neuroleptics action. The present work was, therefore, focused on gene expression of H2S and CO-producing enzymes in the brains of rats chronically treated with olanzapine, an atypical antipsychotic drug. METHODS: Studies were carried out on adult, male Sprague-Dawley rats that were divided into 2 groups: control and experimental animals treated with olanzapine (28-day-long intraperitoneal injection, at a dose of 5 mg/kg daily). All individuals were sacrificed under anesthesia and the whole brains excised. Immunohistochemical procedure was used for histological assessment of the whole brain and for quantitative analysis of cystathionine ß-synthase (CBS) and heme oxygenase 2 (HO-2) protein distribution in selected brain structures. RESULTS: Long-term treatment with olanzapine is reflected in different changes in the number of enzymes-expressing cells in the rat brain. Olanzapine decreased the number of CBS-expressing cells and possibly reduced H2S synthesis in the hippocampus and striatum. The antipsychotic administration increased the number of HO-2 immunopositive cells and probably stimulated the CO production in the hippocampus. CONCLUSIONS: Modulatory effect of olanzapine on cellular mechanisms of gasotransmitter synthesis may be an alternative way of their pharmacological action.

Evaluation of Peripheral Blood Concentrations of Phoenixin, Spexin, Nesfatin-1 and Kisspeptin as Potential Biomarkers of Bipolar Disorder in the Pediatric Population.

There are some initial suggestions in the literature that phoenixin, spexin, nesfatin-1 and kisspeptin may play a role in the pathogenesis of affective disorders. Therefore, they may also be cautiously considered as potential diagnostic or predictive biomarkers of BD. This study aimed to evaluate the levels of the aforementioned neuropeptides in the peripheral blood of children and adolescents with bipolar. This study included 122 individuals: 67 persons with diagnosed bipolar disorder types I and II constituted the study group, and 55 healthy persons were included in the control group. Statistically significant differences in the concentrations of neuropeptides between the control and study groups were noted in relation to nesfatin-1 and spexin (although spexin lost statistical significance after introducing the Bonferroni correction). In a logistic regression analysis, an increased risk of bipolar disorder was noted for a decrease in nesfatin-1 concentration. Lower levels of nesfatin-1 seemed to be a significant risk factor for the development of bipolar disorder types I and II. Furthermore, the occurrence of bipolar disorder was associated with significantly elevated levels of spexin. None of the analyzed neuropeptides was significantly correlated with the number of symptoms of bipolar disorder.

Profiles of interferon-gamma and interleukin-2 in patients after allogeneic hematopoietic stem cell transplantation.

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) may be related to the occurrence of complications, including graft-versus-host disease (GvHD) and infections. The pathogenesis of acute GvHD is connected with T lymphocytes, which identify alloantigens on host's antigen-presenting cells, activate production of interferon-gamma (IFN-gamma) and interleukin-2 (IL-2), and act on the immune effector cells and damage tissues and organs. AIM: The aim of the study was to investigate and distinguish serum concentration profiles of IFN-gamma and IL-2 within a 30-d period after allo-HSCT. METHODS: We enrolled 62 patients, i.e., 30 (48%) male and 32 (52%) female subjects [median age 49.5 (19-68) years], after allo-HSCT from siblings (n = 12) or unrelated donors (n = 50) due to acute myeloid leukemia with myeloablative conditioning (n = 26; 42%) and with non-myeloablative conditioning (n = 36; 58%). All patients were given standard immunosuppressive therapy with cyclosporin-A and methotrexate and pre-transplant antithymocyte globulin in the unrelated setting. Blood samples were collected pre-transplant before and after (on day -1) the conditioning therapy and on days +2,+4, +6, +10, +20, and +30 after allo-HSCT. Serum levels of IL-2 and IFN-gamma were determined using ELISA. RESULTS: Patients were divided into four groups depending on the presence of acute GvHD and clinical manifestations of infection. Group I included patients with neither acute GvHD nor infections [n = 15 (24%)], group II consisted of patients with infections without acute GvHD [n = 17 (27%)], group III was comprised of patients with acute GvHD without infections [n = 9 (15%)], and group IV included patients with both acute GvHD and infections [n = 21 (34%)]. IFN-gamma concentrations were higher in Group II than in other groups on days +20 (P = 0.014) and +30 (P = 0.008). Post-hoc tests showed lower concentrations of IFN-gamma on day +30 in groups I (P = 0.039) and IV (P = 0.017) compared to group II. The levels of IL-2 were mostly undetectable. CONCLUSION: Serum levels of IFN-gamma following allo-HSCT progressively escalate. High serum levels of IFN-gamma are related to infectious complications rather than acute GvHD. Serum concentrations of IL-2 in most patients are undetectable.

Escitalopram alters local expression of noncanonical stress-related neuropeptides in the rat brain via NPS receptor signaling.

BACKGROUND: Neuropeptide S (NPS) is a multifunctional regulatory factor that exhibits a potent anxiolytic activity in animal models. However, there are no reports dealing with the potential molecular relationships between the anxiolytic activity of selective serotonin reuptake inhibitors (SSRIs) and NPS signaling, especially in the context of novel stress-related neuropeptides action. The present work therefore focused on gene expression of novel stress neuropeptides in the rat brain after acute treatment with escitalopram and in combination with neuropeptide S receptor (NPSR) blockade. METHODS: Studies were carried out on adult, male Sprague-Dawley rats that were divided into five groups: animals injected with saline (control) and experimental rats treated with escitalopram (at single dose 10 mg/kg daily), escitalopram and SHA-68, a selective NPSR antagonist (at a single dose of 40 mg/kg), SHA-68 alone and corresponding vehicle (solvent SHA-68) control. To measure anxiety-like behavior and locomotor activity the open field test was performed. All individuals were killed under anaesthesia and the whole brain was excised. Total mRNA was isolated from homogenized samples of the amygdala, hippocampus, hypothalamus, thalamus, cerebellum, and brainstem. Real-time PCR was used for estimation of related NPS, NPSR, neuromedin U (NMU), NMU receptor 2 (NMUR2) and nesfatin-1 precursor nucleobindin-2 (NUCB2) gene expression. RESULTS: Acute escitalopram administration affects the local expression of the examined neuropeptides mRNA in a varied manner depending on brain location. An increase in NPSR and NUCB2 mRNA expression in the hypothalamus and brainstem was abolished by SHA-68 coadministration, while NMU mRNA expression was upregulated after NPSR blockade in the hippocampus and cerebellum. CONCLUSIONS: The pharmacological effects of escitalopram may be connected with local NPSR-related alterations in NPS/NMU/NMUR2 and nesfatin-1 gene expression at the level of selected rat brain regions. A novel alternative mode of SSRI action can be therefore cautiously proposed.

Effect of Escitalopram on the Number of DCX-Positive Cells and NMUR2 Receptor Expression in the Rat Hippocampus under the Condition of NPSR Receptor Blockade.

BACKGROUND: Neuropeptide S (NPS) is a multifunctional regulatory factor that exhibits a potent anxiolytic activity in animal models. However, there are no reports dealing with the potential molecular interactions between the activity of selective serotonin reuptake inhibitors (SSRIs) and NPS signaling, especially in the context of adult neurogenesis and the expression of noncanonical stress-related neuropeptides such as neuromedin U (NMU). The present work therefore focused on immunoexpression of neuromedin U receptor 2 (NMUR2) and doublecortin (DCX) in the rat hippocampus after acute treatment with escitalopram and in combination with selective neuropeptide S receptor (NPSR) blockade. METHODS: Studies were carried out on adult, male Sprague-Dawley rats that were divided into five groups: animals injected with saline (control) and experimental individuals treated with escitalopram (at single dose 10 mg/kg daily), escitalopram + SHA-68, a selective NPSR antagonist (at single dose 40 mg/kg), SHA-68 alone, and corresponding vehicle control. All animals were sacrificed under halothane anaesthesia. The whole hippocampi were quickly excised, fixed, and finally sliced for general qualitative immunohistochemical assessment of the NPSR and NMUR2 expression. The number of immature neurons was enumerated using immunofluorescent detection of doublecortin (DCX) expression within the subgranular zone (SGZ). RESULTS: Acute escitalopram administration affects the number of DCX and NMUR2-expressing cells in the adult rat hippocampus. A decreased number of DCX-expressing neuroblasts after treatment with escitalopram was augmented by SHA-68 coadministration. CONCLUSIONS: Early pharmacological effects of escitalopram may be at least partly connected with local NPSR-related alterations of neuroblast maturation in the rat hippocampus. Escitalopram may affect neuropeptide and DCX-expression starting even from the first dose. Adult neurogenesis may be regulated via paracrine neuropeptide S and NMU-related signaling.

Predictive efficiency of phoenixin, spexin and kisspeptin neuropeptides concentration levels in diagnosis of bipolar disorder in paediatric population. / Skutecznosc predykcyjna stezen neuropeptydów: feniksyny, speksyny i kisspeptyny dla diagnozy choroby afektywnej dwubiegunowej w populacji pediatrycznej.

OBJECTIVES: The aim of the study was to assess concentrations of the following neuropeptides: phoenixin, spexin and kisspeptin in venous blood serum of children and adolescents suffering from bipolar disorder, and by this their predictive efficiency in this disorder. METHODS: The study covered 75 individuals with a mean age of 15.26 years (95% CI: 14.86-15.67), of which the study group comprised of 57 individuals diagnosed with bipolar affective disorder and the control group - 18 individuals with no psychiatric diagnosis and no pharmacological treatment. Phoenixin, spexin and kisspeptin levels were determined in the peripheral venous blood serum. Neuropeptide concentrations were measured with the enzyme-linked immunosorbent assay (ELISA). RESULTS: The mean phoenixin concentration in the studied group equalled 1.57 ng/ml (95% CI: 1.35-1.79), while in the control group - 2.69 ng/ml (95% CI: 2.38-3; U Mann-Whitney test p-value < 0.05). For spexin, these results were 639.65 pg/ml (95% CI: 558.86-720.44) in the studied group, and 354.28 pg/ml (95% CI: 310.33-398.22; U Mann-Whitney test p-value < 0.05) in the control group. The observed differences were statistically significant. The mean concentration of kisspeptin levels in the studied group was 126.02 pg/ml (95% CI: 39.82-212.23; median: 59.85), while in the control group - 54.83 pg/ml (95% CI: 39.23-70.43; median: 51.3; U Mann-Whitney test p-value = 0.29), and the observed difference was not statistically significant. CONCLUSIONS: The occurrence of bipolar disorder symptoms is statistically significantly linked with a decreased phoenixin concentration and to a small degree - with an increased spexin concentration in blood serum of patients. However, it is not linked with the kisspeptin concentration.

Antipsychotics increase steroidogenic enzyme gene expression in the rat brainstem.

BACKGROUND: Neurosteroids are involved in several important brain functions and have recently been considered novel players in the mechanic actions of neuropsychiatric drugs. There are no reports of murine studies focusing on the effect of chronic neurosteroid treatment in parallel with antipsychotics on key steroidogenic enzyme expression and we therefore focused on steroidogenic enzyme gene expression in the brainstem of rats chronically treated with olanzapine and haloperidol. METHODS AND RESULTS: Studies were carried out on adult, male Sprague-Dawley rats which were divided into 3 groups: control and experimental animals treated with olanzapine or haloperidol. Total mRNA was isolated from homogenized brainstem samples for RealTime-PCR to estimate gene expression of related aromatase, 3ß-HSD and P450scc. Long-term treatment with the selected antipsychotics was reflected in the modulation of steroidogenic enzyme gene expression in the examined brainstem region; with both olanzapine and haloperidol increasing aromatase, 3ß-HSD and P450scc gene expression. CONCLUSIONS: The present findings shed new light on the pharmacology of antipsychotics and suggest the existence of possible regulatory interplay between neuroleptic action and steroidogenesis at the level of brainstem neuronal centres.

Proinflammatory cytokines as potential risk factors of acute graft-versus-host disease and infectious complications after allogeneic hematopoietic stem cell transplantation.

OBJECTIVE: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is associated with a risk of graft-versus-host disease (GvHD) and infections. The pathogenesis of acute GvHD is related to T-lymphocytes, which identify alloantigens on host antigen-presenting cells, induce production of interferon (IFN) gamma and interleukin (IL)-2, recruit immune effector cells and destroy tissues and organs. MATERIAL AND METHODS: The study involved 62 patients, 30 (48%) men and 32 (52%) women [median age 49.5; (19-68) years] after myeloablative conditioning (MAC) n = 26 (42%) or reduced intensity conditioning (RIC) n = 36 (58%) therapy before allo-HSCT from a sibling (n = 12) or unrelated (n = 50) donor due to acute myeloid leukemia (AML). All patients received standard immunosuppressive therapy with cyclosporine A and methotrexate plus pre-transplant anti-thymocyte globulin in the unrelated transplant setting. Blood samples were collected pre-transplant before the start of and after conditioning therapy (1 day pre-transplant) and 2, 4, 6, 10, 20, 30 days following allo-HSCT. The analysis of potential risk factors included IL-2 and IFN-gamma concentrations, patients' age, the use of MAC/RIC and CR/non-CR status before transplantation. RESULTS: The statistical analysis revealed that independent risk factors for aGvHD included non-CR status before allo-HSCT [odds ratio (OR) = 10.52, P = 0.040], the use of MAC [hazard ratio (HR) = 4.80, P = 0.007] and a high level of IFN-gamma on day 6 post-transplant (HR = 1.03, P = 0.032). MAC was also the independent risk factor for infectious complications (OR = 4.04, P = 0.024). CONCLUSION: A high level of IFN-gamma on day 6 post-transplant, non-CR status before allo-HSCT and the use of MAC are independent risk factors for aGvHD. MAC is also the independent risk factor of infectious complications.

Olanzapine Increases Neural Chemorepulsant-Draxin Expression in the Adult Rat Hippocampus.

Draxin belongs to the family of inhibitory axon-guiding factors that regulate neuronal migration and axonal spreading in the developing brain. This glycoprotein has recently been considered to play an important role both in hippocampal differentiation and adult neurogenesis in the dentate gyrus. Given that it has been reported that antipsychotic drugs may affect neurite growth and neurogenesis, we have therefore investigated whether chronic treatment with olanzapine modulates draxin immunoreactivity in the adult rat hippocampus. After analysis of local fluorescence intensity, we found a significant increase of draxin immunoexpression both in the subgranular zone (SGZ) and granular zone of the rat hippocampus following long-term olanzapine administration. This study reveals, for the first time, the modulatory effect of the atypical antipsychotic medication olanzapine on expression of the novel chemorepulsive protein draxin in the context of adult neurogenesis regulation. Moreover, this is the first report dealing with pharmacological aspects of draxin signaling. An elevated draxin expression may indirectly support a recently formulated hypothesis that olanzapine may drive adult neurogenesis via paracrine draxin-related signaling. This action of draxin is a new element in the neurogenesis mechanism that may be part of the action of second-generation antipsychotics in the treatment of schizophrenia, indicating more detailed molecular studies are urgently required to fully investigate these potential novel mechanisms of neurogenesis.

Chlorpromazine affects the numbers of Sox-2, Musashi1 and DCX-expressing cells in the rat brain subventricular zone.

BACKGROUND: Adult neurogenesis observed both in the subventricular zone (SVZ) and hippocampus may be regulated and modulated by several endogenous factors, xenobiotics and medications. Classical and atypical antipsychotic drugs are able to affect neuronal and glial cell proliferation in the rat brain. The main purpose of this structural study was to determine whether chronic chlorpromazine treatment affects adult neurogenesis in the canonical sites of the rat brain. At present, the clinical application of chlorpromazine is rather limited; however, it may still represent an important model in basic neuropharmacological and toxicological studies. METHODS: The number of neural progenitors and immature neurons was enumerated using immunofluorescent detection of Sox2, Musashi1 and doublecortin (DCX) expression within SVZ. RESULTS: Chlorpromazine has a depressive effect on the early phase of adult neurogenesis in the rat subventricular zone (SVZ), as the mean number of Sox-2 immunoexpressing cells decreased following treatment. CONCLUSION: Collectively, these results may suggest that long-term treatment with chlorpromazine may decrease neurogenic stem/progenitor cell formation in the rat SVZ and may affect rostral migratory stream formation.

Longitudinal study on novel neuropeptides phoenixin, spexin and kisspeptin in adolescent inpatients with anorexia nervosa - association with psychiatric symptoms.

OBJECTIVES: It is hypothesized that novel neuropeptides such as phoenixin (PNX), spexin (SPX), and kisspeptin (KISS) are involved in the pathogenesis of eating disorders. The study presented here analyzed neuropeptide concentrations during the course of anorexia nervosa (AN) and aimed to correlate those values with anthropometric and psychometric measurements. METHODS: A longitudinal study was carried outin 30 AN adolescent patients and 15 age-matched healthy female controls. Selected neuroprotein serum levels were analyzed in malnourished patients (accAN) and following partial weight recovery (norAN), and these values were compared with the control group. RESULTS: In accAN patients, decreased serum PNX levels were detected while SPX serum concentrations were lower in the accAN and norAN patients. No differences were observed in KISS concentrations in all studied groups. CONCLUSIONS: In malnourished adolescent inpatients with AN, serum PNX and SPX level were decreased. The partial weight recovery normalized PNX concentrations but failed to normalize SPX levels. Therefore these two neuropeptides might be crucial for the etiology and course of the AN. The KISS levels did not change in the course of AN. The PNX levels were associated with some symptoms of eating disorders which may indicate its potential contribution in the regulation of emotions and behaviors in AN.

Spexin-expressing neurons in the magnocellular nuclei of the human hypothalamus.

Neuropeptides are involved in numerous brain activities being responsible for a wide spectrum of higher mental functions. The purpose of this concise, structural and qualitative investigation was to map the possible immunoreactivity of the novel neuropeptide spexin (SPX) within the human magnocellular hypothalamus. SPX is a newly identified peptide, a natural ligand for the galanin receptors (GALR) 2/3, with no molecular structure similarities to currently known regulatory factors. SPX seems to have multiple physiological functions, with an involvement in reproduction and food-intake regulation recently revealed in animal studies. For the first time we describe SPX expressing neurons in the supraoptic (SON) and paraventricular (PVN) nuclei of the human hypothalamus using immunohistochemical and fluorescent methods, key regions involved in the mechanisms of osmotic homeostasis, energy expenditure, consummatory behaviour, reproductive processes, social recognition and stress responses. The vast majority of neurons located in both examined neurosecretory nuclei show abundant SPX expression and this may indirectly implicate a potential contribution of SPX signalling to the hypothalamic physiology in the human brain.

Escitalopram as a modulator of proopiomelanocortin, kisspeptin, Kiss1R and MCHR1 gene expressions in the male rat brain.

Neuropeptides are important, multifunctional regulatory factors of the nervous system, being considered as a novel, atypical sites of antidepressants action. It has already been proven that some of them, such as selective serotonin reuptake inhibitors (SSRI), are able to affect peptidergic pathways in various brain regions. Despite these reports, there is so far no reports regarding the effect of treatment with SSRIs on brain proopiomelanocortin (POMC), kisspeptin, Kiss1R and MCHR1 gene expression. In the current study we examined POMC, kisspeptin, Kiss1R and MCHR1 mRNA expression in the selected brain structures (hypothalamus, hippocampus, amygdala, striatum, cerebellum and brainstem) of rats chronically treated with a 10 mg/kg dose of escitalopram using quantitative Real-Time PCR. Long-term treatment with escitalopram led to the upregulation of MCHR1 expression in the rat amygdala. Kisspeptin mRNA level was also increased in the amygdala, but Kiss1R mRNA expressions were elevated in the hippocampus, hypothalamus and cerebellum. POMC mRNA expressions were in turn decreased in the hippocampus, amygdala, cerebellum and brainstem. These results may support the hypothesis that these neuropeptides may be involved in the site-dependent actions of SSRI antidepressants. This is the first report of the effects of escitalopram on POMC, kisspeptin, Kiss1R and MCHR1 in animal brain. Our findings shed a new light on the pharmacology of SSRIs and may contribute to a better understanding of the alternative, neuropeptide-dependent modes of antidepressant action.

Chronic Antipsychotic Treatment Modulates Aromatase (CYP19A1) Expression in the Male Rat Brain.

Antipsychotic drugs, known as the antagonists of dopaminergic receptors, may also affect a large spectrum of other molecular signaling pathways in the brain. Despite the numerous ongoing studies on neurosteroid action and regulation, there are no reports regarding the influence of extended treatment with typical and atypical neuroleptics on brain aromatase (CYP19A1) expression. In the present study, we assessed for the first time aromatase mRNA and protein levels in the brain of rats chronically (28 days) treated with olanzapine, clozapine, and haloperidol using quantitative real-time PCR, end-point RT-PCR, and Western blotting. Both clozapine and haloperidol, but not olanzapine treatment, led to an increase of aromatase mRNA expression in the rat brain. On the other hand, aromatase protein level remained unchanged after drug administration. These results cast a new light on the pharmacology of examined antipsychotics and contribute to a better understanding of the mechanisms responsible for their action. The present report also underlines the complex nature of potential interactions between neuroleptic pharmacological effects and physiology of brain neurosteroid pathways.

The first identification of nesfatin-1-expressing neurons in the human bed nucleus of the stria terminalis.

Neuropeptides are involved in various brain activities being able to control a wide spectrum of higher mental functions. The purpose of this concise structural investigation was to detect the possible immunoreactivity of the novel multifunctional neuropeptide nesfatin-1 within the human bed nucleus of the stria terminalis (BNST). The BNST is involved in the mechanism of fear learning, integration of stress and reward circuits, and pathogenesis of addiction. Nesfatin-1-expressing neurons were identified for the first time in several regions of the BNST using both immunohistochemical and fluorescent methods. This may implicate a potential contribution of this neuropeptide to the BNST-related mechanisms of stress/reward responses in the human brain.

The GnRH analogues affect novel neuropeptide SMIM20/phoenixin and GPR173 receptor expressions in the female rat hypothalamic-pituitary-gonadal (HPG) axis.

The recently discovered peptide phoenixin (PNX) and its receptor GPR173 are novel factors that exhibit a large spectrum of regulatory activity, especially when considered as a central modulator of GnRH-related hormonal control of reproductive processes. It has been already proven that GnRH agonists and antagonists can modulate peptidergic signalling in the HPG axis. Despite these findings, there is so far no information regarding the influence of treatment with GnRH analogues on SMIM20/phoenixin signalling in the hypothalamic-pituitary-gonadal axis. In the current study, SMIM20/phoenixin and GPR173 mRNA levels were measured in the hypothalamus, pituitary and ovaries of female rats in the dioestrus phase following treatment with GnRH-R agonist (buserelin) and antagonist (cetrorelix) using quantitative real-time PCR. The serum PNX concentrations were also estimated with ELISA technique. The hypothalamic, hypophyseal and especially ovarian levels of SMIM20 mRNA were increased after both buserelin and cetrorelix administration. The GPR173 expressions were in turn decreased in the hypothalamus and pituitary. Treatment with the GnRH analogues led to the modulation of SMIM20/phoenixin and GPR173 mRNA expression in the female rat hypothalamic-pituitary-gonadal axis. By identifying buserelin and cetrorelix as novel modulators of phoenixin signalling in the animal HPG axis, these results cast new light on the GnRH analogues mode of action and contribute to a better understanding of the mechanisms responsible for the hormonal control of reproduction.

Neuroleptics Affect Kisspeptin mRNA Expression in the Male Rat Hypothalamus and Hippocampus.

Introduction: Kisspeptin has a multidirectional neuroendocrinal activity. It is especially considered to be a central regulator of reproductive function. Numerous data proved that neuroleptic administration may affect the peptidergic signaling in the various brain structures. However, there is no information concerning the relationship between treatment with neuroleptics and brain kisspeptin mRNA expression. Methods: We assessed the kisspeptin mRNA level in the hypothalamus and hippocampus of rats shortly and chronically (28 days) treated with haloperidol, chlorpromazine, and olanzapine using a quantitative Real-Time PCR method. Results: We have shown that all studied neuroleptics injected chronically have the ability to downregulate the kisspeptin mRNA expression in the hypothalamus, which may suggest the presence of an alternative mechanism for their orexigenic side effects. Long-term treatment with chlorpromazine increased the level of kisspeptin mRNA expression in the hippocampus. Discussion: Our results shed a new light on the pharmacology of antipsychotics and may contribute to a better understanding of alternative mechanisms responsible for their action. The study also highlights a complex nature of potential connections between dopamine transmission and brain kisspeptin pathways.