NPFFR2 Activates the HPA Axis and Induces Anxiogenic Effects in Rodents

Brain RFamide Neuropeptides in Stress-Related Psychopathologies

The RFamide peptide family is a group of proteins that share a common C-terminal arginine-phenylalanine-amide motif. To date, the family comprises five groups in mammals: neuropeptide FF, LPXRFamides/RFamide-related peptides, prolactin releasing peptide, QRFP, and kisspeptins. Different RFamide peptides have their own cognate receptors and are produced by different cell populations, although they all can also bind to neuropeptide FF receptors with different affinities. RFamide peptides function in the brain as neuropeptides regulating key aspects of homeostasis such as energy balance, reproduction, and cardiovascular function. Furthermore, they are involved in the organization of the stress response including modulation of pain. Considering the interaction between stress and various parameters of homeostasis, the role of RFamide peptides may be critical in the development of stress-related neuropathologies. This review will therefore focus on the role of RFamide peptides as possible key hubs in stress and stress-related psychopathologies. The neurotransmitter coexpression profile of RFamide-producing cells is also discussed, highlighting its potential functional significance. The development of novel pharmaceutical agents for the treatment of stress-related disorders is an ongoing need. Thus, the importance of RFamide research is underlined by the emergence of peptidergic and G-protein coupled receptor-based therapeutic targets in the pharmaceutical industry.

NPFFR2-deficient mice fed a high-fat diet develop strong intolerance to glucose

A previous study on neuropeptide FF receptor 2 (NPFFR2)-deficient mice has demonstrated that NPFFR2 is involved in the control of energy balance and thermogenesis. Here, we report on the metabolic impact of NPFFR2 deficiency in male and female mice that were fed either a standard diet (STD) or a high-fat diet (HFD) and each experimental group consisted of ten individuals. Both male and female NPFFR2 knockout (KO) mice exhibited severe glucose intolerance that was exacerbated by a HFD diet. In addition, reduced insulin pathway signaling proteins in NPFFR2 KO mice fed a HFD resulted in the development of hypothalamic insulin resistance. HFD feeding did not cause liver steatosis in NPFFR2 KO mice of either sex, but NPFFR2 KO male mice fed a HFD had lower body weights, white adipose tissues, and liver and lower plasma leptin levels compared with their wild-type (WT) controls. Lower liver weight in NPFFR2 KO male mice compensated for HFD-induced metabolic stress by increased liver PPARα and plasma FGF21 hepatokine, which supported fatty acid β-oxidation in the liver and white adipose tissue. Conversely, NPFFR2 deletion in female mice attenuated the expression of Adra3β and Pparγ, which inhibited lipolysis in adipose tissue.

NPFFR2 gene compound heterozygous variants associated with preeclampsia identified by whole-exome sequencing

BACKGROUND

Preeclampsia (PE) is an idiopathic disorder of pregnancy. The exact cause of PE remains unknown. Emerging evidence indicates that the cause of PE is linked to genetic factors. Therefore, the aim of this study was to identify the susceptibility genes for PE.

METHODS

Nine families with severe PE were recruited. The whole-exome sequencing (WES) was performed on each family, and Sanger sequencing was used to identify the potential pathogenic genetic variants.

RESULTS

After a rigorous bioinformatics analysis, compound heterozygous variants in the NPFFR2 gene, NM_004885.2: c.601A > G, p.Met201Val and c.995C > T, p.Ala332Val were found in the No.4 pedigree. Bioinformatics analysis showed that these sites were highly conserved among several species and were predicted to be pathogenic variants according to multiple online mutational function prediction software packages. Due to the compound heterozygous variants of NPFFR2, more bonds are generated between mutant amino acids and spatial adjacent amino acids, which may lead to more stable active conformation of protein and not easy to be degraded.

CONCLUSIONS

We demonstrated for the first time that compound heterozygous variants of the NPFFR2 gene might be potentially associated with severe PE, the results of this study provide clinicians and researchers with a better understanding of the molecular mechanisms underlying severe PE in pregnant women.

DNA methylation in cocaine use disorder-An epigenome-wide approach in the human prefrontal cortex

BACKGROUND

Cocaine use disorder (CUD) is characterized by a loss of control over cocaine intake and is associated with structural, functional, and molecular alterations in the human brain. At the molecular level, epigenetic alterations are hypothesized to contribute to the higher-level functional and structural brain changes observed in CUD. Most evidence of cocaine-associated epigenetic changes comes from animal studies while only a few studies have been performed using human tissue.

METHODS

We investigated epigenome-wide DNA methylation (DNAm) signatures of CUD in human post-mortem brain tissue of Brodmann area 9 (BA9). A total of N = 42 BA9 brain samples were obtained from N = 21 individuals with CUD and N = 21 individuals without a CUD diagnosis. We performed an epigenome-wide association study (EWAS) and analyzed CUD-associated differentially methylated regions (DMRs). To assess the functional role of CUD-associated differential methylation, we performed Gene Ontology (GO) enrichment analyses and characterized co-methylation networks using a weighted correlation network analysis. We further investigated epigenetic age in CUD using epigenetic clocks for the assessment of biological age.

RESULTS

While no cytosine-phosphate-guanine (CpG) site was associated with CUD at epigenome-wide significance in BA9, we detected a total of 20 CUD-associated DMRs. After annotation of DMRs to genes, we identified Neuropeptide FF Receptor 2 (NPFFR2) and Kalirin RhoGEF Kinase (KALRN) for which a previous role in the behavioral response to cocaine in rodents is known. Three of the four identified CUD-associated co-methylation modules were functionally related to neurotransmission and neuroplasticity. Protein-protein interaction (PPI) networks derived from module hub genes revealed several addiction-related genes as highly connected nodes such as Calcium Voltage-Gated Channel Subunit Alpha1 C (CACNA1C), Nuclear Receptor Subfamily 3 Group C Member 1 (NR3C1), and Jun Proto-Oncogene, AP-1 Transcription Factor Subunit (JUN). In BA9, we observed a trend toward epigenetic age acceleration (EAA) in individuals with CUD remaining stable even after adjustment for covariates.

CONCLUSION

Results from our study highlight that CUD is associated with epigenome-wide differences in DNAm levels in BA9 particularly related to synaptic signaling and neuroplasticity. This supports findings from previous studies that report on the strong impact of cocaine on neurocircuits in the human prefrontal cortex (PFC). Further studies are needed to follow up on the role of epigenetic alterations in CUD focusing on the integration of epigenetic signatures with transcriptomic and proteomic data.

Anxiety and Depression: What Do We Know of Neuropeptides?

In modern society, there has been a rising trend of depression and anxiety. This trend heavily impacts the population’s mental health and thus contributes significantly to morbidity and, in the worst case, to suicides. Modern medicine, with many antidepressants and anxiolytics at hand, is still unable to achieve remission in many patients. The pathophysiology of depression and anxiety is still only marginally understood, which encouraged researchers to focus on neuropeptides, as they are a vast group of signaling molecules in the nervous system. Neuropeptides are involved in the regulation of many physiological functions. Some act as neuromodulators and are often co-released with neurotransmitters that allow for reciprocal communication between the brain and the body. Most studied in the past were the antidepressant and anxiolytic effects of oxytocin, vasopressin or neuropeptide Y and S, or Substance P. However, in recent years, more and more novel neuropeptides have been added to the list, with implications for the research and development of new targets, diagnostic elements, and even therapies to treat anxiety and depressive disorders. In this review, we take a close look at all currently studied neuropeptides, their related pathways, their roles in stress adaptation, and the etiology of anxiety and depression in humans and animal models. We will focus on the latest research and information regarding these associated neuropeptides and thus picture their potential uses in the future.

NPFF Decreases Activity of Human Arcuate NPY Neurons: A Study in Embryonic-Stem-Cell-Derived Model

Restoring the control of food intake is the key to obesity management and prevention. The arcuate nucleus (ARC) of the hypothalamus is extensively being studied as a potential anti-obesity target. Animal studies showed that neuropeptide FF (NPFF) reduces food intake by its action in neuropeptide Y (NPY) neurons of the hypothalamic ARC, but the detailed mode of action observed in human neurons is missing, due to the lack of a human-neuron-based model for pharmacology testing. Here, we validated and utilized a human-neural-stem-cell-based (hNSC) model of ARC to test the effects of NPFF on cellular pathways and neuronal activity. We found that in the human neurons, decreased cAMP levels by NPFF resulted in a reduced rate of cytoplasmic calcium oscillations, indicating an inhibition of ARC NPY neurons. This suggests the therapeutic potential of NPFFR2 in obesity. In addition, we demonstrate the use of human-stem-cell-derived neurons in pharmacological applications and the potential of this model to address functional aspects of human hypothalamic neurons.

Elevated Serum Neuropeptide FF Levels Are Associated with Cognitive Decline in Patients with Spinal Cord Injury

BACKGROUND

Spinal cord injury (SCI) has high incidence globally and is frequently accompanied by subsequent cognitive decline. Accurate early risk-categorization of SCI patients for cognitive decline using biomarkers can enable the timely application of appropriate neuroprotective measures and the development of new agents for the management of SCI-associated cognitive decline. Neuropeptide FF is an endogenous neuropeptide with a multitude of functions and is associated with neuroinflammatory processes. This prospective study investigated the predictive value of serum neuropeptide FF levels measured after acute SCI for subsequent cognitive decline.

METHODS

88 patients presenting with acute SCI without preexisting neurological injury, brain trauma, or severe systemic illness and 60 healthy controls were recruited. Serum neuropeptide FF levels, clinical, and routine laboratory variables including low-density lipoprotein, high-density lipoprotein, fasting blood glucose, total triiodothyronine (TT3), total thyroxine (TT4), and thyroid-stimulating hormone (TSH) levels collected from all subjects were assessed. Montreal cognitive assessment (MoCA) was performed 3 months after enrollment. SCI patients were grouped according to quartile of serum neuropeptide FF level and MoCA scores were compared using ANOVA. Additionally, multivariate linear regression with clinical and laboratory variables was performed to predict MoCA scores.

RESULTS

SCI patients displayed significantly higher baseline serum neuropeptide FF levels than healthy controls (38.5 ± 4.1 versus 23.4 ± 2.0 pg/ml, p < 0.001∗∗). SCI patients in higher quartiles of baseline serum neuropeptide FF displayed significantly lower MoCA scores at 3 months. Linear regression analysis indicated serum neuropeptide FF levels as a significant independent predictor of worse MoCA scores after SCI (r = 0.331, p = 0.034∗).

CONCLUSION

Early serum neuropeptide FF levels significantly and independently predicted cognitive decline after acute SCI among patients without preexisting neurological disorders.

Lack of neuropeptide FF signalling in mice leads to reduced repetitive behavior, altered drinking behavior, and fuel type selection

Although best known for their involvement in modulating nociception, Neuropeptide FF (NPFF) group peptides have been suggested to fulfil a variety of biological functions such as feeding, anxiety behaviors and thermogenesis. However, evidence supporting these functions of NPFF is mostly pharmacological, leaving the physiological relevance unaddressed. Here we examined the physiological impact of lack of NPFF signalling in both genders using a Npff^-/- mouse model. NPFF expression in the mouse is restricted to the spinal cord and brainstem while its cognate receptor NPFFR2 has wider distribution throughout the brain. Both male and female Npff^-/- mice showed reduced repetitive behaviors evidenced in the marble burying test and self-grooming test. A decrease in anxiety-related behaviors in the Npff^-/- mice was also observe in the open field test and to a lesser degree in an elevated plus maze test. Moreover, both male and female Npff^-/- mice exhibited increased water intake resulting from increases in drinking size, rather than number of drinking events. During a fasting-refeeding challenge, Npff^-/- mice of both genders displayed alterations in reparatory exchange ratio that reflect a greater fuel type flexibility. Npff^-/- mice were otherwise wild-type-like regarding body weight, body composition, feeding behaviors, locomotion or energy expenditure. Together, these findings reveal the important physiological roles of NPFF signalling in the regulation of anxiety-related and repetitive behaviors, fluid homeostasis and oxidative fuel selection, highlighting the therapeutical potential of the NPFF system in a number of behavioral and metabolic disorders.

Single-nucleus transcriptome analysis reveals cell-type-specific molecular signatures across reward circuitry in the human brain

Single-cell gene expression technologies are powerful tools to study cell types in the human brain, but efforts have largely focused on cortical brain regions. We therefore created a single-nucleus RNA-sequencing resource of 70,615 high-quality nuclei to generate a molecular taxonomy of cell types across five human brain regions that serve as key nodes of the human brain reward circuitry: nucleus accumbens, amygdala, subgenual anterior cingulate cortex, hippocampus, and dorsolateral prefrontal cortex. We first identified novel subpopulations of interneurons and medium spiny neurons (MSNs) in the nucleus accumbens and further characterized robust GABAergic inhibitory cell populations in the amygdala. Joint analyses across the 107 reported cell classes revealed cell-type substructure and unique patterns of transcriptomic dynamics. We identified discrete subpopulations of D1- and D2-expressing MSNs in the nucleus accumbens to which we mapped cell-type-specific enrichment for genetic risk associated with both psychiatric disease and addiction.

DNA methylation changes following narrative exposure therapy in a randomized controlled trial with female former child soldiers

The aftermath of traumatization lives on in the neural and epigenetic traces creating a momentum of affliction in the psychological and social realm. Can psychotherapy reorganise these memories through changes in DNA methylation signatures? Using a randomised controlled parallel group design, we examined methylome-wide changes in saliva samples of 84 female former child soldiers from Eastern DR Congo before and six months after Narrative Exposure Therapy. Treatment predicted differentially methylated positions (DMPs) related to ALCAM, RIPOR2, AFAP1 and MOCOS. In addition, treatment associations overlapped at gene level with baseline clinical and social outcomes. Treatment related DMPs are involved in memory formation-the key agent in trauma focused treatments-and enriched for molecular pathways commonly affected by trauma related disorders. Results were partially replicated in an independent sample of 53 female former child soldiers from Northern Uganda. Our results suggest a molecular impact of psychological treatment in women with war-related childhood trauma.Trial registration: Addressing Heightened Levels of Aggression in Traumatized Offenders With Psychotherapeutic Means (ClinicalTrials.gov Identifier: NCT02992561, 14/12/2016).

Transcriptomic Changes in Mouse Bone Marrow-Derived Macrophages Exposed to Neuropeptide FF

Neuropeptide FF (NPFF) is a neuropeptide that regulates various biological activities. Currently, the regulation of NPFF on the immune system is an emerging field. However, the influence of NPFF on the transcriptome of primary macrophages has not been fully elucidated. In this study, the effect of NPFF on the transcriptome of mouse bone marrow-derived macrophages (BMDMs) was explored by RNA sequencing, bioinformatics, and molecular simulation. BMDMs were treated with 1 nM NPFF for 18 h, followed by RNA sequencing. Differentially expressed genes (DEGs) were obtained, followed by GO, KEGG, and PPI analysis. A total of eight qPCR-validated DEGs were selected as hub genes. Subsequently, the three-dimensional (3-D) structures of the eight hub proteins were constructed by Modeller and Rosetta. Next, the molecular dynamics (MD)-optimized 3-D structure of hub protein was acquired with Gromacs. Finally, the binding modes between NPFF and hub proteins were studied by Rosetta. A total of 2655 DEGs were obtained (up-regulated 1442 vs. down-regulated 1213), and enrichment analysis showed that NPFF extensively regulates multiple functional pathways mediated by BMDMs. Moreover, the 3-D structure of the hub protein was obtained after MD-optimization. Finally, the docking modes of NPFF-hub proteins were predicted. Besides, NPFFR2 was expressed on the cell membrane of BMDMs, and NPFF 1 nM significantly activated NPFFR2 protein expression. In summary, instead of significantly inhibiting the expression of the immune-related gene transcriptome of RAW 264.7 cells, NPFF simultaneously up-regulated and down-regulated the gene expression profile of a large number of BMDMs, hinting that NPFF may profoundly affect a variety of cellular processes dominated by BMDMs. Our work provides transcriptomics clues for exploring the influence of NPFF on the physiological functions of BMDMs.

Long-term antibiotic use during early life and risks to mental traits: an observational study and gene-environment-wide interaction study in UK Biobank cohort

The relationships between long-term antibiotic use during early life and mental traits remain elusive now. A total of 158,444 subjects from UK Biobank were used in this study. Linear regression analyses were first conducted to assess the correlations between long-term antibiotic use during early life and mental traits. Gene-environment-wide interaction study (GEWIS) was then performed by PLINK2.0 to detect the interaction effects between long-term antibiotic use during early life and genes on the risks of mental traits. Finally, DAVID tool was used to conduct gene ontology (GO) analysis of the identified genes interacting with long-term antibiotic use during early life. We found negative associations of long-term antibiotic use during early life with remembrance (p value=1.74 × 10^-6, b = -0.10) and intelligence (p value=2.64 × 10^-26, b = -0.13), and positive associations of long-term antibiotic use during early life with anxiety (p value = 2.75 × 10^-47, b = 0.12) and depression (p value=2.01 × 10^-195, b = 0.25). GEWIS identified multiple significant genes-long-term antibiotic use during early life interaction effects, such as ANK3 (rs773585997, p value = 1.78 × 10^-8) for anxiety and STRN (rs140049205, p value = 1.88 × 10^-8) for depression. GO enrichment analysis detected six GO terms enriched in the identified genes interacting with long-term antibiotic use during early life for anxiety, such as GO:0030425~dendrite (p value = 3.41 × 10^-2) and GO:0005886~plasma membrane (p value = 3.64 × 10^-3). Our study results suggest the impact of long-term antibiotic use during early life on the development of mental traits.

Prognostic plasma exosomal microRNA biomarkers in patients with substance use disorders presenting comorbid with anxiety and depression

Psychiatric disorders such as anxiety and depression precipitated by substance use occurred during both use and withdrawal. Exosomes play significant roles in biological functions and regulate numerous physiological and pathological processes in various diseases, in particular substance use disorders (SUDs) and other psychiatric disorders. To better understand the role of exosomal miRNAs in the pathology of symptoms of anxiety and depression in patients with SUDs, we first isolated circulating exosomes from heroin-dependent patients (HDPs) and methamphetamine-dependent patients (MDPs) and identified exosomal miRNAs that were differentially expressed between patients and healthy controls (HCs). Furthermore, the correlations between exosomal DE-miRNAs and symptoms of anxiety and depression which were measured using Hamilton-Anxiety (HAM-A)/Hamilton-Depression (HAM-D) Rating Scales in the participants. Notably, the expression level of exosomal hsa-miR-16-5p, hsa-miR-129-5p, hsa-miR-363-3p, and hsa-miR-92a-3p showed significantly negative correlations with HAM-A scores in both HDPs and MDPs. But all of the 4 DE-miRNAs lost significant correlations with HAM-D scores in HDPs. Functional annotation analyses showed that the target genes of the DE-miRNAs were mainly enriched for “synapse”, “cell adhesion”, “focal adhesion” and “MHC class II protein complex”. Our study suggests that a set of circulating exosomal miRNAs were associated with anxiety and depression in SUD patients and may have clinical utility as diagnostic and prognostic biomarkers.

Cellular processes involved in RAW 264.7 macrophages exposed to NPFF: A transcriptional study

Neuropeptide FF (NPFF) is a neuropeptide that modulates various physiological processes. The regulatory role of NPFF in the immune and inflammatory response is currently being revealed. However, the effect of NPFF at the transcriptome level in macrophages has not been fully elucidated. Here, the impact of NPFF on gene expression at the transcriptome level of RAW 264.7 cells was investigated by RNA-seq. RAW 264.7 macrophages were treated with NPFF (1 nM) for 18 h, followed by RNA-seq examination. Differentially expressed genes (DEGs) were acquired, followed by GO, KEGG, and PPI analysis. A total of eight qPCR-verified DEGs were obtained. Next, three-dimensional models of the eight hub proteins were constructed by using homology modeling with Modeller (9v23). Finally, molecular dynamics simulation (300 ns) was performed with GROMACS 2018.2 to investigate the structural characteristics of these hub proteins. NPFF had no detectable effect on the morphology of RAW264.7 cells. A total of 211 DEGs were acquired, and an enrichment study demonstrated that the immune response-related pathway was significantly inhibited by NPFF. Moreover, the molecular dynamics optimized-protein models of the hub proteins were obtained. Collectively, NPFF inhibited the expression of immune-related genes in RAW 264.7 cells at the transcriptome level, which suggested a negative relationship between NPFF and this set of immune-related genes in RAW 264.7 macrophages. Therefore, our data may provide direct evidence of the role of NPFF in peripheral or central inflammatory diseases.

Ablation of NPFFR2 in Mice Reduces Response to Single Prolonged Stress Model

Mental stress is highly related to many clinical symptoms and disorders, as it activates the hypothalamic-pituitary-adrenocortical (HPA) axis to affect a wide variety of physiological functions. Furthermore, stress leads to the aberrations in HPA axis activity and disruptions of body homeostasis. It was previously shown that neuropeptide FF (NPFF) regulates the HPA axis through the activation of hypothalamus paraventricular nucleus (PVN), and genetic overexpression or pharmacological stimulation of NPFF receptor 2 (NPFFR2) triggers hyperactivity of HPA axis and suppresses behavioral correlates of emotion in mice. In this study, we further examined the role of NPFFR2 in stress response in mice by utilizing a single prolonged stress (SPS). SPS is considered a model of post-traumatic stress disorder (PTSD), and mice undergo physical restraint, forced swimming, and ether anesthesia within a day followed by social isolation for one week. NPFFR2 knockout B6 mice were generated by CRISPR/Cas9 technology and exposed to SPS. The NPFFR2 knockouts showed resistance to stress exposure-induced anxiety-like behaviors and HPA axis hyperactivity. Additionally, the hippocampal mRNA levels of glucocorticoid receptor and mineralocorticoid receptor were reduced in wild-type (WT) mice but not in NPFFR2 knockouts after stress exposure. Our data also suggested that NPFFR2 knockout mice have stronger negative feedback on the HPA axis after exposure to SPS. Mice with intra-PVN Npffr2 shRNA injection displayed trends toward resistance to SPS exposure in both behavioral and molecular assays. Together, our findings suggest that NPFFR2 may be a potential therapeutic target for disorders relating to stress/anxiety and HPA dysregulation.

Neuropeptide FF and Its Receptors: Therapeutic Applications and Ligand Development

The endogenous neuropeptide FF (NPFF) and its two cognate G protein-coupled receptors, Neuropeptide FF Receptors 1 and 2 (NPFFR1 and NPFFR2), represent a relatively new target system for many therapeutic applications including pain regulation, modulation of opioid side effects, drug reward, anxiety, cardiovascular conditions, and other peripheral effects. Since the cloning of NPFFR1 and NPFFR2 in 2000, significant progress has been made to understand their pharmacological roles and interactions with other receptor systems, notably the opioid receptors. A variety of NPFFR ligands with different mechanisms of action (agonists or antagonists) have been discovered although with limited subtype selectivities. Differential pharmacological effects have been observed for many of these NPFFR ligands, depending on assays/models employed and routes of administration. In this Perspective, we highlight the therapeutic potentials, current knowledge gaps, and latest updates of the development of peptidic and small molecule NPFFR ligands as tool compounds and therapeutic candidates.

Endogenous opiates and behavior: 2017

This paper is the fortieth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2017 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).

Identification of a 3-mRNA signature as a novel potential prognostic biomarker in patients with ovarian serous cystadenocarcinoma in G2 and G3

The use of mRNAs as biomarkers serves to diagnose, treat, as well as aid the prognosis of cancer. The present study involved an analysis of mRNAs in the cell cycle at the G2 and G3 tumor grades for the prognosis of ovarian serous cystadenocarcinoma (OSC) using 364 clinical samples (G2:G3=42:322). Statistics aided the identification of NPFFR2, XPNPEP2 and CELA3B; the 3-mRNA model that allows for classification of patients into high- and low-risk groups using a median value of 0.9580745. The rates of survival varied (P=0.00149) and the independent detection of stratification of the risk of this disease was validated with success using the 3-mRNA signature, which was demonstrated to be more successful than the weight model. This approach was revealed to provide the prognosis of grade G2 and G3 in patients with OSC compared with factors used traditionally. Compared with traditional factors, this 3-mRNA model was demonstrated to be the only and independent prognostic factor for patients with G2 and G3 stage OSC. A literature survey was also performed in the present study in order to assess the role of the 3 genes and indirectly prove their effectiveness. The establishment of this new genetic model will enhance prospective prognosis and treatment for patients with OSC.

Neuropeptide FF modulates neuroendocrine and energy homeostasis through hypothalamic signaling

Neuropeptide FF (NPFF) is known as a morphine-modulating peptide and was first isolated in 1985. It has been characterized as an RF-amide peptide. The traditional role of NPFF is mediation of the pain response, and it displays both anti-opioid and pro-opioid actions through central nervous system. In the recent decade, additional evidence has revealed some untraditional features of NPFF, such as regulation of the neuroendocrine system, energy homeostasis, anti-inflammation, pain transmission, and peripheral modulation of adipose tissue macrophages. Neuropeptide FF receptor 2 (NPFFR2) is a physiological receptor of NPFF, and the actions of NPFF may occur through downstream NPFFR2 signaling. NPFF and NPFFR2 increase the neuronal activity in various areas of the hypothalamus to modulate the hypothalamic-pituitary-adrenal axis, the autonomic nervous system, food intake, and energy balance. These underlying cellular mechanisms have been explored in the past few years. Here, we review the impact of NPFF and related RF-amide peptides on hypothalamic function. The interaction of NPFF with NPFFR2 in the hypothalamus is emphasized, and NPFF-NPFFR2 system may represent an important therapeutic target in hypothalamic-related disorders in the future.