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Many G protein-coupled receptors (GPCRs) initiate a second phase of stimulatory heterotrimeric G protein (Gs)-coupled cAMP signaling after endocytosis. The prevailing current view is that the endosomal signal is inherently β-arrestin-dependent because β-arrestin is necessary for receptor internalization and, for some GPCRs, to prolong the endosomal signal. Here we revise this view by showing that the vasoactive intestinal peptide receptor 1 (VIPR1), a secretin-family polypeptide hormone receptor, does not require β-arrestin to internalize or to generate an endosomal signal. β-Arrestin instead resolves the plasma membrane and endosomal signaling phases into sequential cAMP peaks by desensitizing the plasma membrane phase without affecting the endosomal phase. This appears to occur through the formation of functionally distinct VIPR1-β-arrestin complexes at each location that differ in their phosphorylation dependence. We conclude that endosomal GPCR signaling can occur in the absence of β-arrestin and that β-arrestin sculpts the spatiotemporal profile of cellular GPCR-G protein signaling through location-specific remodeling of GPCR-β-arrestin complexes.

Background: Ketamine has emerged as a prominent substance of misuse. Leptin, an adipocyte-derived polypeptide hormone, has been implicated in the development of addiction. Sex-specific changes in leptin levels have been demonstrated following acute ketamine administration; the persistence of long-term ketamine use on leptin levels is uncertain.Objectives: To assess the sex-difference of leptin levels, and their persistence, in individuals with ketamine use disorder (KUD) compared to healthy controls.Methods: Plasma leptin levels were measured in 62 healthy controls (37 males, 25 females) and 68 participants with KUD (50 males, 18 females) on the first day (baseline) and after 1 and 2 weeks of abstinence. As leptin levels are affected by body mass index (BMI), BMI-adjusted leptin (leptin/BMI ratio) was also examined. Mixed model for repeated measures was used to examine changes after ketamine abstinence.Results: Compared to same-sex controls, female, but not male, participants with KUD demonstrated lower leptin levels and leptin/BMI ratio at baseline, week 1, and week 2 (leptin levels: p = .001, 0.006 and 0.032, respectively; leptin/BMI ratio: p = .004, 0.022, and 0.09, respectively). Repeated measures showed that leptin levels and the leptin/BMI ratio increased after 2 weeks of abstinence in male participants with KUD (p = .002 and 0.011, respectively), but females did not show such an increase (p > .05).Conclusions: Sex-specific differences were observed in leptin levels and the leptin/BMI ratio in individuals with KUD compared to controls. Lower leptin levels in females with KUD persisted after 2 weeks of abstinence. [ABSTRACT FROM AUTHOR]

Endothelin type B receptor (ETBR) plays a crucial role in regulating blood pressure and humoral homeostasis, making it an important therapeutic target for related diseases. ETBR activation by the endogenous peptide hormones endothelin (ET)−1–3 stimulates several signaling pathways, including Gs, Gi/o, Gq/11, G12/13, and β-arrestin. Although the conserved NPxxY motif in transmembrane helix 7 (TM7) is important during GPCR activation, ETBR possesses the lesser known NPxxL motif. In this study, we present the cryo-EM structure of the ETBR–Gi complex, complemented by MD simulations and functional studies. These investigations reveal an unusual movement of TM7 to the intracellular side during ETBR activation and the essential roles of the diverse NPxxL motif in stabilizing the active conformation of ETBR and organizing the assembly of the binding pocket for the α5 helix of Gi protein. These findings enhance our understanding of the interactions between GPCRs and G proteins, thereby advancing the development of therapeutic strategies. Tani et al. present the cryo-EM structure of the endothelin type B receptor (ETBR) in complex with the Gi protein, emphasizing the movements of transmembrane helix 7 during ETBR activation. The study underscores the crucial role of the NPxxL motif in stabilizing the receptor's active state and organizing the Gi protein binding site, enhancing our understanding of GPCR activation and aiding therapeutic development. [ABSTRACT FROM AUTHOR]

In cardiogenic shock, biomarkers should ideally help make the diagnosis, choose the right therapeutic options and monitor the patient in addition to clinical and echocardiographic indices. Among "old" biomarkers that have been used for decades, lactate detects, quantifies, and follows anaerobic metabolism, despite its lack of specificity. Renal and liver biomarkers are indispensable for detecting the effect of shock on organ function and are highly predictive of poor outcomes. Direct biomarkers of cardiac damage such as cardiac troponins, B-type natriuretic and N-terminal pro-B-type natriuretic peptides have a good prognostic value, but they lack specificity to detect a cardiogenic cause of shock, as many factors influence their plasma concentrations in critically ill patients. Among the biomarkers that have been more recently described, dipeptidyl peptidase-3 is one of the most interesting. In addition to its prognostic value, it could represent a therapeutic target in cardiogenic shock in the future as a specific antibody inhibits its activity. Adrenomedullin is a small peptide hormone secreted by various tissues, including vascular smooth muscle cells and endothelium, particularly under pathological conditions. It has a vasodilator effect and has prognostic value during cardiogenic shock. An antibody inhibits its activity and so adrenomedullin could represent a therapeutic target in cardiogenic shock. An increasing number of inflammatory biomarkers are also of proven prognostic value in cardiogenic shock, reflecting the inflammatory reaction associated with the syndrome. Some of them are combined to form prognostic proteomic scores. Alongside clinical variables, biomarkers can be used to establish biological "signatures" characteristic of the pathophysiological pathways involved in cardiogenic shock. This helps describe patient subphenotypes, which could in the future be used in clinical trials to define patient populations responding specifically to a treatment. [ABSTRACT FROM AUTHOR]

Quiescence is an essential property of meristematic cells, which restrains the cell cycle while retaining the capacity to divide. This crucial process not only facilitates life-long tissue homeostasis and regenerative capacity but also provides protection against adverse environmental conditions, enabling cells to conserve the proliferative potency while minimizing DNA damage. As a survival attribute, quiescence is inherently regulated by the products of aerobic life, in particular reactive oxygen species (ROS) and the redox (reduction/oxidation) mechanisms that plant have evolved to channel these into pervasive signals. Adaptive responses allow quiescent cells to compensate for reduced oxygen tension (hypoxia) in a reversible manner, while the regulated production of the superoxide anion (O2·−) facilitates cell division and the maintenance of stem cells. Here we discuss the role of ROS and redox reactions in the control of the quiescent state in plant meristems, and how this process is integrated with cellular energy and hormone biochemistry. We consider the pathways that sense and transmit redox signals with a focus on the central significance of redox regulation in the mitochondria and nucleus, which is a major regulator of quiescence in meristems. We discuss recent studies that suggest that ROS are a critical component of the feedback loops that control stem cell identity and fate, and suggest that the ROS/hypoxia interface is an important 'outside/in' positional cue for plant cells, particularly in meristems. [ABSTRACT FROM AUTHOR]

The theoretical foundations of understanding psychiatric disorders are undergoing changes. Explaining behaviour and neuroendocrine cell communication leaning towards immunology represents a different approach compared to previous models for understanding complex central nervous system processes. One such approach is the study of immunoglobulins or autoantibodies, and their effect on peptide hormones in the neuro-endocrine system. In the present review, we provide an overview of the literature on neuropeptide/transmitter and autoantibody modulation in psychiatric disorders featuring emotional problems and aggression, including associated illness behaviour. Finally, we discuss the role of psycho-immunology as a growing field in the understanding of psychiatric disorders, and that modulation and regulation by IgG autoAbs represent a relatively new subcategory in psychoimmunology, where studies are currently being conducted. [ABSTRACT FROM AUTHOR]

Background: Different responses in human coronary arteries (HCA) and human middle meningeal arteries (HMMA) were observed for some of the novel CGRP receptor antagonists, the gepants, for inhibiting CGRP-induced relaxation. These differences could be explained by the presence of different receptor populations in the two vascular beds. Here, we aim to elucidate which receptors are involved in the relaxation to calcitonin gene-related peptide (CGRP), adrenomedullin (AM) and adrenomedullin 2 (AM2) in HCA and HMMA. Methods: RNA was isolated from homogenized human arteries (23 HCAs; 12 F, 11 M, age 50 ± 3 years and 26 HMMAs; 14 F, 12 M, age 51 ± 3 years) and qPCR was performed for different receptor subunits. Additionally, relaxation responses to CGRP, AM or AM2 of the human arteries were quantified using a Mulvany myograph system, in the presence or absence of the adrenomedullin 1 receptor antagonist AM22-52 and/or olcegepant. Results: Calcitonin-like receptor (CLR) mRNA was expressed equally in both vascular beds, while calcitonin receptor (CTR) and receptor activity-modifying protein 3 (RAMP3) expression was low and could not be detected in all samples. RAMP1 expression was similar in HCA and HMMA, while RAMP2 expression was higher in HMMA. Moreover, receptor component protein (RCP) expression was higher in HMMA than in HCA. Functional experiments showed that olcegepant inhibits relaxation to all three agonists in both vascular beds. In HCA, antagonist AM22-52 did not inhibit relaxation to any of the agonists, while a trend for blocking relaxation to AM and AM2 could be observed in HMMA. Conclusion: Based on the combined results from receptor subunit mRNA expression and the functional responses in both vascular tissues, relaxation of HCA is mainly mediated via the canonical CGRP receptor (CLR-RAMP1), while relaxation of HMMA can be mediated via both the canonical CGRP receptor and the adrenomedullin 1 receptor (CLR-RAMP2). Future research should investigate whether RAMP2 predominance over RAMP1 in the meningeal vasculature results in altered migraine susceptibility or in a different response to anti-migraine medication in these patients. Moreover, the exact role of RCP in CGRP receptor signalling should be elucidated in future research. [ABSTRACT FROM AUTHOR]

Systemin, the first peptide hormone identified in plants, was initially isolated from tomato (Solanum lycopersicum) leaves. Systemin mediates local and systemic wound‐induced defense responses in plants, conferring resistance to necrotrophic fungi and herbivorous insects. Systemin is recognized by the leucine‐rich‐repeat receptor‐like kinase (LRR‐RLK) receptor SYSTEMIN RECEPTOR1 (SYR1), but how the systemin recognition signal is transduced to intracellular signaling pathways to trigger defense responses is poorly understood. Here, we demonstrate that SERK family LRR‐RLKs function as co‐receptors for SYR1 to mediate systemin signal transduction in tomato. By using chemical genetic approaches coupled with engineered receptors, we revealed that the association of the cytoplasmic kinase domains of SYR1 with SERKs leads to their mutual trans‐phosphorylation and the activation of SYR1, which in turn induces a wide range of defense responses. Systemin stimulates the association between SYR1 and all tomato SERKs (SlSERK1, SlSERK3A, and SlSERK3B). The resulting SYR1‐SlSERK heteromeric complexes trigger the phosphorylation of TOMATO PROTEIN KINASE 1B (TPK1b), a receptor‐like cytoplasmic kinase that positively regulates systemin responses. Additionally, upon association with SYR1, SlSERKs are cleaved by the Pseudomonas syringae effector HopB1, further supporting the finding that SlSERKs are activated by systemin‐bound SYR1. Finally, genetic analysis using Slserk mutants showed that SlSERKs are essential for systemin‐mediated defense responses. Collectively, these findings demonstrate that the systemin‐mediated association of SYR1 and SlSERKs activates defense responses against herbivorous insects. [ABSTRACT FROM AUTHOR]

Background: B-type natriuretic peptides (BNP) and cardiac enzymes are both recognized biomarkers of heart health. Many studies have reported that using these indicators can assess cardiac condition and predict prognosis of patients undergoing surgery. Currently little is known on the effect of increased cardiac input after venous recanalization on cardiac physiology in patients with chronic venous obstruction (CVO). Objectives: The aim of this study was to explore the effect of iliocaval recanalization and stenting on cardiac biomarkers in patients with CVO. Methods: This was a prospective study involving 60 patients in a single unit. Blood tests were collected 1 day before and 1 day after venous intervention. Three groups as group 1: patients with iliofemoral post-thrombotic syndrome (PTS) but without involvement of inferior vena cava (IVC) (n = 33); group 2: patients with iliofemoral PTS and involvement of IVC (n = 19) and group 3: patients with non-thrombotic vein lesion (NIVL) (n = 8) were compared based on cardiac biomarker levels. Results: Median concentration of post-operative BNP (259.60 pg/mL) was greater than preoperative levels (49.80 pg/mL) [interquartile range (IQR), 147.15/414.68 versus 29.85/82.88; p < 0.001]. The levels of CK-MB [preop: 3 U/l (IQR, 1.40/11.00) versus postop: 14 U/l (IQR, 12/17), p < 0.001] and troponin T [preop: 3.00 pg/mL (IQR, 3.00/5.25) versus postop: level of 6 pg/mL (IQR, 3.00/9.50), p < 0.001]. Post-procedure increases in cardiac enzymes showed significant differences in BNP (p = 0.023) and troponin T (p = 0.007) across the three groups, while CK-MB levels were not significantly different (p > 0.05). Intergroup comparisons of postoperative BNP: group 1 versus group 2 (p = 0.013), group 2 versus group 3 (p = 0.029), group 1 versus group 3 (p = 0.834); and postoperative troponin T: group 1 versus group 2 (p = 0.018), group 2 versus group 3 (p = 0.002), group 1 versus group 3 (p = 0.282). According to multiple linear regression analysis, length of stenting and level of preoperative BNP were independent determinants of postoperative BNP levels (p < 0.05), and preoperative troponin T affected postoperative troponin T independently (p < 0.05). Conclusions: Troponin T, CK-MB and BNP seem to increase after venous recanalization and stent implantation, the elevation being more prominent for longer lesions. [ABSTRACT FROM AUTHOR]

The peptide hormone kisspeptin attenuates liver steatosis, metabolic dysfunction-associated steatohepatitis (MASH), and fibrosis in mouse models by signaling via the kisspeptin 1 receptor (KISS1R). However, whether kisspeptin impacts fibrogenesis in the human liver is not known. We investigated the impact of a potent kisspeptin analog (KPA) on fibrogenesis using human precision-cut liver slices (hPCLS) from fibrotic livers from male patients, in human hepatic stellate cells (HSCs), LX-2, and in primary mouse HSCs. In hPCLS, 48 h and 72 h of KPA (3 nM, 100 nM) treatment decreased collagen secretion and lowered the expression of fibrogenic and inflammatory markers. Immunohistochemical studies revealed that KISS1R is expressed and localized to HSCs in MASH/fibrotic livers. In HSCs, KPA treatment reduced transforming growth factor b (TGFβ)-the induced expression of fibrogenic and inflammatory markers, in addition to decreasing TGFβ-induced collagen secretion, cell migration, proliferation, and colony formation. Mechanistically, KISS1R signaling downregulated TGFβ signaling by decreasing SMAD2/3 phosphorylation via the activation of protein phosphatases, PP2A, which dephosphorylates SMAD 2/3. This study revealed for the first time that kisspeptin reverses human hepatic fibrogenesis, thus identifying it as a new therapeutic target to treat hepatic fibrosis. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a chronic, progressive, degenerative joint disease characterized by joint pain, stiffness, and limited movement. It presents significant intra- and inter-individual variability—in particular, between genders. Recent research has increasingly focused on the role of adipokines—especially leptin, adiponectin, and resistin—in the development of OA. Adipokines, peptide hormones primarily secreted by adipose tissue, are involved in crucial physiological processes related to metabolism and immunity. They can also impact bone and cartilage turnover by interacting with joint cells such as osteoblasts, osteoclasts, chondrocytes, and mesenchymal stem cells, thereby linking inflammation with bone cartilage homeostasis. This review aims to elucidate the structure and functions of various adipokines, their serum and synovial levels, and their association with clinical presentation and radiographic progression in OA patients, with a focus on differences between sexes. A narrative literature review was conducted using three databases specifically analyzing sex differences. OA patients generally show elevated serum and synovial levels of leptin, chemerin, and visfatin, as well as high plasma levels of resistin and visfatin. In contrast, synovial levels of adiponectin and omentin are reduced in OA patients compared to healthy individuals, with an inverse relationship to disease severity, suggesting a potential protective role. Resistin and leptin were positively correlated with pain severity and radiographic progression, while adiponectin's role in OA remains controversial. Regarding sex differences, male OA patients exhibited higher serum levels of leptin, chemerin, and omentin compared to healthy controls, with a positive correlation to the BMI and estrogen levels, potentially explaining the sexual dimorphism observed in this condition. Studies on visfatin and lipocalin did not reveal significant differences in synovial or serum levels between the sexes. The role of resistin remains controversial. Adipokines influence the joint microenvironment and contribute to the progression of osteoarthritis (OA). However, the precise biological mechanisms are not yet fully understood due to the complex interactions between the metabolic, mechanical, and immune systems. Further research is needed to clarify their roles in OA and to identify targeted therapies for managing this degenerative disease. [ABSTRACT FROM AUTHOR]

The extracellular matrix plays an integrative role in cellular responses in plants, but its contribution to the signalling of extracellular ligands largely remains to be explored. Rapid alkalinisation factors (RALFs) are extracellular peptide hormones that play pivotal roles in various physiological processes. Here, we address a crucial connection between the de- methylesterification machinery of the cell wall component pectin and RALF1 activity. Pectin is a polysaccharide, contributing to the structural integrity of the cell wall. Our data illustrate that the pharmacological and genetic interference with pectin methyl esterases (PMEs) abolishes RALF1-induced root growth repression. Our data suggest that positively charged RALF1 peptides bind negatively charged, de-methylesterified pectin with high avidity. We illustrate that the RALF1 association with de-methylesterified pectin is required for its FERONIA- dependent perception, contributing to the control of the extracellular matrix and the regulation of plasma membrane dynamics. Notably, this mode of action is independent of the FER-dependent extracellular matrix sensing mechanism provided by FER interaction with the leucine-rich repeat extensin (LRX) proteins. We propose that the methylation status of pectin acts as a contextualizing signalling scaffold for RALF peptides, linking extracellular matrix dynamics to peptide hormone-mediated responses. [ABSTRACT FROM AUTHOR]

The purpose of this study is to analyze the early clinical features of coronary artery lesion (CAL) in Kawasaki disease (KD), evaluate systemic inflammation indicators, and enhance early recognition of CAL in the acute phase of KD. A total of 314 children with KD were divided into those with CAL (CAL group) and without CAL (NCAL group) using echocardiographic results, and their clinical data were retrospectively analyzed. For KD patients, male, children aged 3 to 9 years, and those with fever longer than 6 days before intravenous immunoglobulin (IVIG) use were more likely to have CAL. There were significant differences in sex, age, and fever time (P <.05). Moreover, some laboratory indicator test results revealed there was a significant difference between N-terminal pro-brain natriuretic peptide (NT-pro-BNP) and interleukin-6 (IL-6), and the CAL (P <.05). This study has certain guiding significance for early clinical evaluation. [ABSTRACT FROM AUTHOR]

The article focuses on an 11-year-old boy presenting with slurred speech and involuntary movements, later diagnosed with a neurological disorder. Topics include his clinical symptoms such as dysarthria and abnormal involuntary movements, his physical exam findings including hyperreflexia and abnormal gait, and the absence of significant prior medical or family history.

Dormancy is an essential ecological characteristic for the survival of organisms that experience harsh environments. Although factors that initiate dormancy vary, suppression or cessation of feeding activities are common among taxa. To distinguish between extrinsic and intrinsic causes of metabolic reduction, we focused on estivation, which occurs in summer when the feeding activity is generally enhanced. Sand lances (genus Ammodytes) are a unique marine fish with a long estivation period from early summer to late autumn. In the present study, we aimed to elucidate the control mechanisms of estivation in western sand lance (A. japonicus), and firstly examined behavioral changes in 8 months including a transition between active and dormant phases. We found that swimming/feeding behavior gradually decreased from June, and completely disappeared by late August, indicating all individuals had entered estivation. Next, we focused on leptin, known as a feeding suppression hormone in various organisms, and examined leptin‐A gene (AjLepA) expression in the brain that may regulate the seasonal behavioral pattern. AjLepA expression decreased after 7 days of fasting, suggesting that leptin has a function to regulate feeding in this species. The monthly expression dynamics of AjLepA during the feeding (active) and non‐feeding (estivation) periods showed that the levels gradually increased with the onset of estivation and reached its peak when all the experimental fish had estivated. The present study suggests that the suppression of feeding activity by leptin causes shift in the physiological modes of A. japonicus before estivation. Research highlights: Sand lance spends in sand for more than half a year without feeding, a unique dormancy among teleosts called estivationLeptin, a peptide hormone, was found to be involved in appetite suppression in brain and work to exert the onset of estivation [ABSTRACT FROM AUTHOR]

Stanniocalcin (STC) 1 and 2 serve as antihyperglycemic polypeptide hormones with critical roles in regulating calcium and phosphate homeostasis. They additionally function as paracrine and/or autocrine factors involved in numerous physiological processes, including female reproduction. STC1 and STC2 contribute to the pathophysiology of several diseases, including female infertility- and pregnancy-associated conditions, and even tumorigenesis of reproductive organs. This comprehensive review highlights the dynamic expression patterns and potential dysregulation of STC1 and STC2, restricted to female fertility, and infertility- and pregnancy-associated diseases and conditions, such as endometriosis, polycystic ovary syndrome (PCOS), abnormal uterine bleeding, uterine polyps, and pregnancy complications, like impaired decidualization, preeclampsia, and preterm labor. Furthermore, the review elucidates the role of dysregulated STC in the progression of cancers of the reproductive system, including endometrial, cervical, and ovarian cancers. Additionally, the review evaluates the expression patterns and prognostic significance of STC in gynecological cancers by utilizing existing public datasets from The Cancer Genome Atlas to help decipher the multifaceted roles of these pleiotropic hormones in disease progression. Understanding the intricate mechanisms by which STC proteins influence all these reviewed conditions could lead to the development of targeted diagnostic and therapeutic strategies in the context of female reproductive health and oncology. [ABSTRACT FROM AUTHOR]

ABSTRACT Posttranslational tyrosine sulfation of peptides and proteins is catalysed by tyrosylprotein sulfotransferases (TPSTs). In Arabidopsis, tyrosine sulfation is essential for the activities of peptide hormones, such as phytosulfokine (PSK) and root meristem growth factor (RGF). Here, we identified a TPST‐encoding gene, MtTPST, from model legume Medicago truncatula. MtTPST expression was detected in all organs, with the highest level in root nodules. A promoter:GUS assay revealed that MtTPST was highly expressed in the root apical meristem, nodule primordium and nodule apical meristem. The loss‐of‐function mutant mttpst exhibited a stunted phenotype with short roots and reduced nodule number and size. Application of both of the sulfated peptides PSK and RGF3 partially restored the defective root length of mttpst. The reduction in symbiotic nodulation in mttpst was partially recovered by treatment with sulfated PSK peptide. MtTPST‐PSK module functions downstream of the Nod factor signalling to promote nodule initiation via regulating accumulation and/or signalling of cytokinin and auxin. Additionally, the small‐nodule phenotype of mttpst, which resulted from decreased apical meristematic activity, was partially complemented by sulfated RGF3 treatment. Together, these results demonstrate that MtTPST, through its substrates PSK, RGF3 and other sulfated peptide(s), positively regulates nodule development and root growth. [ABSTRACT FROM AUTHOR]

Background: Traumatic brain injury is a kind of injury caused by external violence on the head. Its danger is not limited to life rescue in the early stage of the disease. Moreover, the subsequent inflammatory reaction and the change in its oxidative stress level will cause secondary myocardial injury. The purpose of this study is to explore the myocardial protective effect of ozone autohemotherapy (OA) in the progression of acute traumatic brain injury (TBI). Methods: Forty patients with acute TBI were recruited and divided into The treatment group (Group OA, n = 18) and the Control group (Group C, n = 19). Patients in Group OA received OA before surgery and on the 1st and 2nd postoperative days, while patients in Group C underwent autologous blood transfusion. Venous blood was collected from all patients before (T0) and after 7 days (T1) days of surgery for measurement of cardiac troponin T (cTnT) and amino-terminal pro-B-type natriuretic peptide (NT-proBNP). At T0 and T1, transthoracic cardiac ultrasound was performed to measure left ventricular ejection fraction (LVEF), tricuspid annular plane systolic excursion (TAPSE), and venous blood was sampled to determine the contents of superoxide dismutase (SOD) and malondialdehyde (MDA). NIH Stroke Scale (NIHSS) and Glasgow Coma Scale (GCS) scores were calculated, and other clinical indexes were recorded. Results: (1) The levels of cTnT at T1 were significantly higher as compared with that at T0 in both groups (p < 0.01). Compared with Group C, a remarkable decline in the content of NT-proBNP was found in Group OA at T1 (p = 0.021). (2) The LVEF (p = 0.002) and serum SOD (p = 0.015) at T1 were significantly increased in Group OA as compared with those in Group C. (3) The length of Intensive Care Unit and hospitalization time for patients in Group OA was distinctly shorter than that for patients in Group C (p = 0.021, p = 0.015, respectively). Conclusion: Perioperative OA treatment can alleviate the secondary myocardial injury during the disease course of TBI, which might be associated with its myocardial protective effect against oxidative stress. Trial registration: This study was approved by the Ethical Committee of Changzhou NO.2 People's Hospital. The protocol was registered prospectively with the Chinese Clinical Trial Registry (ChiCTR2000029612) on February 02, 2020. [ABSTRACT FROM AUTHOR]

Female sexual receptivity is essential for reproduction of a species. Neuropeptides play the main role in regulating female receptivity. However, whether neuropeptides regulate female sexual receptivity during the neurodevelopment is unknown. Here, we found the peptide hormone prothoracicotropic hormone (PTTH), which belongs to the insect PG (prothoracic gland) axis, negatively regulated virgin female receptivity through ecdysone during neurodevelopment in Drosophila melanogaster. We identified PTTH neurons as doublesex-positive neurons, they regulated virgin female receptivity before the metamorphosis during the third-instar larval stage. PTTH deletion resulted in the increased EcR-A expression in the whole newly formed prepupae. Furthermore, the ecdysone receptor EcR-A in pC1 neurons positively regulated virgin female receptivity during metamorphosis. The decreased EcR-A in pC1 neurons induced abnormal morphological development of pC1 neurons without changing neural activity. Among all subtypes of pC1 neurons, the function of EcR-A in pC1b neurons was necessary for virgin female copulation rate. These suggested that the changes of synaptic connections between pC1b and other neurons decreased female copulation rate. Moreover, female receptivity significantly decreased when the expression of PTTH receptor Torso was reduced in pC1 neurons. This suggested that PTTH not only regulates female receptivity through ecdysone but also through affecting female receptivity associated neurons directly. The PG axis has similar functional strategy as the hypothalamic-pituitary-gonadal axis in mammals to trigger the juvenile-adult transition. Our work suggests a general mechanism underlying which the neurodevelopment during maturation regulates female sexual receptivity. [ABSTRACT FROM AUTHOR]

In humans, 15 genes encode the class B1 family of GPCRs, which are polypeptide hormone receptors characterized by having a large N-terminal extracellular domain (ECD) and receive signals from outside the cell to activate cellular response. For example, the insulinotropic polypeptide (GIP) stimulates the glucose-dependent insulinotropic polypeptide receptor (GIPR), while the glucagon receptor (GCGR) responds to glucagon by increasing blood glucose levels and promoting the breakdown of liver glycogen to induce the production of insulin. The glucagon-like peptides 1 and 2 (GLP-1 and GLP-2) elicit a response from glucagon-like peptide receptor types 1 and 2 (GLP1R and GLP2R), respectively. Since these receptors are implicated in the pathogenesis of diabetes, studying their activation is crucial for the development of effective therapies for the condition. With more structural information being revealed by experimental methods such as X-ray crystallography, cryo-EM, and NMR, the activation mechanism of class B1 GPCRs becomes unraveled. The available crystal and cryo-EM structures reveal that class B1 GPCRs follow a two-step model for peptide binding and receptor activation. The regions close to the C-termini of hormones interact with the N-terminal ECD of the receptor while the regions close to the N-terminus of the peptide interact with the TM domain and transmit signals. This review highlights the structural details of class B1 GPCRs and their conformational changes following activation. The roles of MD simulation in characterizing those conformational changes are briefly discussed, providing insights into the potential structural exploration for future ligand designs. [ABSTRACT FROM AUTHOR]

GPRC6A, a member of the Family C G‐protein coupled receptors, regulates energy metabolism and sex hormone production and is activated by diverse ligands, including cations, L‐amino acids, the osteocalcin (Ocn) peptide and the steroid hormone testosterone. We sought a structural framework for the ability of multiple distinct classes of ligands to active GPRC6A. We created a structural model of GPRC6A using Alphafold2. Using this model we explored a putative orthosteric ligand binding site in the bilobed Venus fly trap (VFT) domain of GPRC6A and two positive allosteric modulator (PAM) sites, one in the VFT and the other in the 7 transmembrane (7TM) domain. We provide evidence that Ocn peptides act as a PAM for GPRC6A by binding to a site in the VFT that is distinct from the orthosteric site for calcium and L‐amino acids. In agreement with this prediction, alternatively spliced GPRC6A isoforms 2 and 3, which lack regions of the VFT, and mutations in the computationally predicted Ocn binding site, K352E and H355P, prevent Ocn activation of GPRC6A. These observations explain how dissimilar ligands activate GPRC6A and set the stage to develop novel molecules to activate and inhibit this previously poorly understood receptor. [ABSTRACT FROM AUTHOR]

Background: Angiotensin II is a peptide hormone vasopressor that activates angiotensin type 1 (AT1) receptors leading to vasoconstriction, the augmentation of arterial blood pressure (ABP), and organ perfusion. Angiotensin II was found to increase the ABP in catecholamine-refractory vasodilatory shock. Whether this effect improves the chances of survival or not remains inconclusive. Therefore, we conducted a systematic review and meta-analysis to evaluate the efficacy and safety of angiotensin II in vasoplegic shock. Objectives: To evaluate the clinical significance of angiotensin II effects in vasoplegic shock concerning the hemodynamic impact, mortality outcomes, and side effects. Methods: Following PRISMA guidelines, we searched PubMed and EMBASE for experimental and observational studies published in English exploring the clinical outcomes of angiotensin II use in vasodilatory shock till 1 July 2024. Two independent authors assessed the quality and risk of bias of the included studies. A random effect model (Mantel–Haenszel) was used to combine data. The primary outcome was in-hospital mortality associated with angiotensin II use in comparison to standard therapy, while the secondary outcomes were mean arterial pressure (MAP) change, multi-organ failure (MOF), and the incidence of atrial fibrillation (AF). The Q test and I2 were used to examine heterogeneity, with I2 > 50% indicating marked heterogeneity. Results: A total of eight studies (n = 974) comparing angiotensin II to standard therapy in vasoplegic shock were included in the systematic review, with three studies comprising 461 patients included in the final analysis of the primary outcome. Only one study evaluated the use of angiotensin II as a primary vasopressor, while the rest reported angiotensin II use in catecholamine-refractory vasodilatory shock. Overall, angiotensin II use was associated with similar in-hospital mortality compared to standard therapy (risk ratio [RR] = 0.83; 95% CI, 0.68–1.02, I2 = 0%). Likewise, there was no difference in MOF and AF (MOF: RR = 1.01; 95% CI, 0.61–1.65, I2 = 0%; AF: RR = 1.27; 95% CI, 0.38–4.23, I2 = 5%). However, angiotensin II use demonstrated a significant MAP increase (mean difference = −9.60; 95% CI, −9.71, −9.49, I2 = 0%). Conclusions: In vasodilatory shock, angiotensin II use demonstrated comparable in-hospital mortality compared to standard therapy. Nevertheless, it resulted in significant MAP change, which may encourage clinicians to use it in cases of profound hypotension. [ABSTRACT FROM AUTHOR]

Using personification and the first person techniques, this article provides a brief introduction to the peptide hormone oxytocin in the form of a Blog, including its basic overview, research history, and functional effects. It also conducts analogical analysis with related substances, using vivid and interesting language to help people form a preliminary understanding of oxytocin. [ABSTRACT FROM AUTHOR]

Protein amyloid aggregation is linked with widespread and fatal neurodegenerative disorders as well as several amyloidoses. Insulin, a small polypeptide hormone, is associated with injection-site amyloidosis and is a popular model protein for in vitro studies of amyloid aggregation processes as well as in the search for potential anti-amyloid compounds. Despite hundreds of studies conducted with this specific protein, the procedures used have employed a vast array of different means of achieving fibril formation. These conditions include the use of different solution components, pH values, ionic strengths, and other additives. In turn, this variety of conditions results in the generation of fibrils with different structures, morphologies and stabilities, which severely limits the possibility of cross-study comparisons as well as result interpretations. In this work, we examine the condition–structure relationship of insulin amyloid aggregation under a range of commonly used pH and ionic strength conditions as well as solution components. We demonstrate the correlation between the reaction solution properties and the resulting aggregation kinetic parameters, aggregate secondary structures, morphologies, stabilities and dye-binding modes. [ABSTRACT FROM AUTHOR]

Glutaminyl cyclase (QC) and its isoenzyme (isoQC) catalyze the formation of N-terminal pyroglutamate (pGlu) from glutamine on a number of neuropeptides, peptide hormones and chemokines. Chemokines of the C-C ligand (CCL) motif family are known to contribute to inflammation in neurodegenerative conditions. Here, we used a model of transient focal cerebral ischemia to explore functional, cellular and molecular responses to ischemia in mice lacking genes for QC, isoQC and their substrate CCL2. Mice of the different genotypes were evaluated for functional consequences of stroke, infarct volume, activation of glia cells, and for QC, isoQC and CCL2 expression. The number of QC-immunoreactive, but not of isoQC-immunoreactive, neurons increased robustly in the infarct area at 24 and 72 h after ischemia. In parallel, immunohistochemical signals for the QC substrate CCL2 increased from 24 to 72 h after ischemia induction without differences between genotypes analyzed. The increase in CCL2 was accompanied by morphological activation of Iba1-immunoreactive microglia and recruitment of MHC-II-positive cells at 72 h after ischemia. Among other chemokines quantified in the brain tissue, CCL17 showed higher concentrations at 72 h compared to 24 h after ischemia. Collectively, these data suggest a critical role for QC in inflammatory processes in the stroke-affected brain. [ABSTRACT FROM AUTHOR]

Background Cardiac injury caused by iron overload is the leading cause of mortality and morbidity in patients with beta-thalassemia, owing to frequent blood transfusion, increased iron overload, and blood hemolysis. Objective This research aimed to assess several novel cardiac biomarkers in the blood samples of children and adult patients with beta-thalassemia major (βTM), along with their respective control groups. These biomarkers included endothelin 1 (ET-1), N-terminal pro-brain natriuretic peptide (NT-proBNP), atrial natriuretic peptide (ANP), growth differentiation factor-15 (GDF-15), and renalase (RNLS). Methods This case-control study was done on 46 patients with βTM (23 children <18 years, and 23 adults ≥18 years) from the Genetic Hematology Center in Thi-Qar province, Iraq, and 42 comparable controls in 2 groups (21 for each group) in the period from February to April 2023. Results Levels of ET-1, NT-proBNP, ANP, GDF-15, RNLS, and ferritin were higher in the children and adults with βTM than in the control subjects. Conclusion Elevations of the novel cardiac biomarkers ET-1, NT-proBNP, ANP, GDF-15, and RNLS in the sera of children and adult patients with βTM when compared with comparable control subjects confirm that the majority of patients with βTM are at risk of cardiac and cardiovascular complications even when there are no obvious symptoms, especially in children, which gives suitable predictive biomarkers. [ABSTRACT FROM AUTHOR]

The Australian Scleroderma Interest Group (ASIG) algorithm for screening pulmonary arterial hypertension (PAH) in systemic sclerosis (SSc) requires only respiratory function tests and serum N‐terminal pro‐brain natriuretic peptide as first‐tier tests, and is recommended in international guidelines. In this communication, we present the findings of the application of the ASIG screening algorithm to a Singaporean cohort undergoing prospective annual screening for PAH, which shows a high negative predictive value. The ASIG algorithm may offer an alternative to more complex and costly SSc‐PAH screening algorithms. [ABSTRACT FROM AUTHOR]

Introduction: It has been suggested that inhibin B (InhB), Anti-Müllerian hormone (Müllerian-inhibiting substance, AMH) levels, and 2D/4D finger length ratios are related to sex differences in neurodevelopmental disorders. The aim of this study is to investigate the role of InhB, AMH levels, and 2D/4D finger length ratios in male children with specific learning disorder (SLD). Methods: The study included 38 male children diagnosed with SLD and 38 males of similar ages without SLD as the control group. Tests used in the evaluation were the Kiddie Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime version, Specific learning disorder clinical observation battery, Wechsler Intelligence Scale for Children-Revised (WISC-R), and Conners' Parent Rating Scale-Revised: Short Form. Serum AMH, InhB, and Testosterone levels were measured using an enzyme-linked immunosorbent assay. Results: Male children diagnosed with SLD demonstrated significantly higher levels of serum InhB compared to controls (t= 2.59 p=0.009); both groups had similar levels of serum testosterone and AMH. The 2D/4D finger ratios in the SLD group were found to be lower than those in the control group (t= 2.92 p= 0.005). Serum InhB levels were positively correlated with WISC-R verbal scores (p= 0.003). Conclusion: Our findings suggest that serum InhB levels and the 2D/4D ratio, which is an indicator of prenatal testosterone exposure, may play a role in the male predominance of SLD. [ABSTRACT FROM AUTHOR]

Oxytocin (OXT) is a peptide hormone and a neuropeptide that regulates various peripheral physiological processes and modulates behavioral responses in the central nervous system. While the humoral release occurs from the axons arriving at the median eminence, the neuropeptide is also released from oxytocinergic cell axons in various brain structures that contain its receptor, and from their dendrites in hypothalamic nuclei and potentially into the cerebrospinal fluid (CSF). Understanding oxytocin's complex functions requires the knowledge on patterns of oxytocinergic projections in relationship to its receptor (OXTR). This study provides the first comprehensive examination of the oxytocinergic system in the prairie vole (Microtus ochrogaster), an animal exhibiting social behaviors that mirror human social behaviors linked to oxytocinergic functioning. Using light and electron microscopy, we characterized the neuroanatomy of the oxytocinergic system in this species. OXT+ cell bodies were found primarily in the hypothalamus, and axons were densest in subcortical regions. Examination of the OXT+ fibers and their relationship to oxytocin receptor transcripts (Oxtr) revealed that except for some subcortical structures, the presence of axons was not correlated with the amount of Oxtr across the brain. Of particular interest, the cerebral cortex that had high expression of Oxtr transcripts contained little to no fibers. Electron microscopy is used to quantify dense cored vesicles (DCV) in OXT+ axons and to identify potential axonal release sites. The ependymal cells that line the ventricles were frequently permissive of DCV-containing OXT+ dendrites reaching the third ventricle. Our results highlight a mechanism in which oxytocin is released directly into the ventricles and circulates throughout the ventricular system, may serve as the primary source for oxytocin that binds to OXTR in the cerebral cortex. [ABSTRACT FROM AUTHOR]

Introduction: Endurance exercise at altitude can increase cardiac output and pulmonary vascular pressure to levels that may exceed the stress tolerability of the alveolar--capillary unit. This study examined the effect of ultramarathon trail racing at different altitudes (ranging from <1000 m to between 1500 and 2700 m) on alveolar--capillary recruitment and lung diffusion. Methods: Cardiac and lung function were examined before and after an ultramarathon in 67 runners (age: 41 ± 9 yr, bodymass index: 23 ± 2 kg⋅m-2, 10 females), and following 12-24 h of recovery in a subset (n = 27). Cardiac biomarkers (cTnI and BNP) were assessed from whole blood, whereas lung fluid accumulation (comet tails), stroke volume (SV), and cardiac output (Q)were quantified via echocardiography. Lung diffusing capacity for carbonmonoxide (DLco) and its components, alveolar membrane conductance (Dm) and capillary blood volume (Vc), were determined via a single-breath method at rest and during three stages of submaximal semirecumbent cycling (20, 30, and 40W). Results:Average race time was 25 ± 12 h. From pre- to post-race, there was an increase in cardiac biomarkers (cTnI: 0.04 ± 0.02 vs 0.13 ± 0.03 ng⋅mL-1,BNP: 20 ± 2 vs 112 ± 21 pg⋅mL-1; P < 0.01) and lung comet tails (2 ± 1 vs 7 ± 6, P < 0.01), a decrease in resting and exercise SV (76 ± 2 vs 69 ± 2 mL, 40 W: 93 ± 2 vs 88 ± 2 mL; P < 0.01), and an elevation in Q at rest (4.1 ± 0.1 vs 4.6 ± 0.2 L⋅min-1, P < 0.01; 40 W: 7.3 ± 0.2 vs 7.4 ± 0.3 L⋅min-1, P = 0.899). Resting DLco and Vc decreased after the race ( P < 0.01), whereas Dm was unchanged ( P = 0.465); however, during the three stages of exercise, DLco, Vc, and Dm were all reduced from pre- to post-race (40 W: 36.3 ± 0.9 vs 33.0 ± 0.8 mL⋅min-1⋅mm Hg-1, 83 ± 3 vs 73 ± 2 mL, 186 ± 6 vs 170 ± 7 mL⋅min-1⋅mm Hg-1, respectively; P < 0.01). When corrected for alveolar volume and Q, DLco decreased from pre- to post-race ( P < 0.01), and changes in DLco were similar for all ultramarathon events ( P > 0.05). Conclusions: Competing in an ultramarathon leads to a transient increase in cardiac injury biomarkers, mild lung-fluid accumulation, and impairments in lung diffusion. Reductions in DLco are predominantly caused by a reduced Vc and possible pulmonary capillary de-recruitment at rest. However, impairments in alveolar--capillary recruitment and Dm both contribute to a fall in exertional DLco following an ultramarathon. Perturbations in lung diffusion were evident across a range of event distances and varying environmental exposures. [ABSTRACT FROM AUTHOR]

Natriuretic peptides (NP) play an essential role in heart failure (HF) regulation, and their measurement has improved diagnostic and prognostic accuracy. Clinical symptoms and objective measurements, such as NP levels, should be included in the HF definition to render it more reliable and consistent among observers, hospitals, and healthcare systems. BNP and NT-proBNP are reasonable surrogates for cardiac disease, and their measurement is critical to early diagnosis and risk stratification of HF patients. NPs should be measured in all patients presenting with dyspnea or other symptoms suggestive of HF to facilitate early diagnosis and risk stratification. Both BNP and NT-proBNP are currently used for guided HF management and display comparable diagnostic and prognostic accuracy. Standardized cutoffs for each NP assay are essential for data comparison. The value of NP testing is recognized at various levels, including patient empowerment and education, analytical and operational issues, clinical HF management, and cost-effectiveness. [ABSTRACT FROM AUTHOR]

Loss of osteogenic differentiation potential of osteoblasts has been associated with the pathogenesis of osteoporosis. Thus, stimulation of osteoblastic differentiation is a therapeutic strategy for osteoporosis. Relaxin‐2 is a peptide hormone with potent biological functions. However, the effects of Relaxin‐2 in osteoblastic differentiation and osteoporosis have not been reported before. Here, we report a novel physiological role of Relaxin‐2 in promoting osteoblastic differentiation and mineralization of MC3T3‐E1 cells. Our results indicate that exposure to Relaxin‐2 upregulated the expression, and elevated the activity of alkaline phosphatase (ALP) when MC3T3‐E1 cells were cultured in osteogenic differentiation medium (OM). Additionally, Relaxin‐2 upregulated the mRNA levels of osteocalcin (ocn), osteopontin (opn), and collagen type I alpha 1 (Col1a1). The alizarin red S staining assay revealed that Relaxin‐2 promoted the mineralization of MC3T3‐E1 cells. We also found that Relaxin‐2 increased the expression of Runx‐2 as well as the epidermal growth factor (EGF) and epidermal growth factor receptor (EGFR). Importantly, silencing of EGF abolished the effects of Relaxin‐2 in osteoblastic differentiation and related gene expression. These findings suggest that Relaxin‐2 stimulates osteogenic differentiation through activating EGF/EGFR signaling. [ABSTRACT FROM AUTHOR]

Hormones are specific molecules measured in biological fluids by elaborate analytical systems requiring meticulous attention. Variation between laboratories can be expected. However, recently published measurements of AVP, OXT, and BNP in human plasma under basal/control conditions include numbers which, between publications, vary by 100–10 000‐fold. Generally, the methods descriptions are scant, at best, and provide no information about quality control measures. Clearly, two results describing the same basal hormone concentration by numbers three orders of magnitude apart are incongruent providing reason for concern. Basal concentrations of bioactive AVP, OXT, and BNP in human plasma are in the order of 1–10 pmol/L. Therefore, assay systems applied to plasma must be able to measure concentrations of less than 1 pmol/L with appropriate specificity and accuracy. Basal concentrations of AVP, OXT, and BNP above 100 pmol/L should be reconsidered, as such results do not reflect bioactive hormone levels in humans, rats, or mice. Any concentration above 1000 pmol/L is of concern because such levels of bioactive hormone may be seen only under extreme conditions, if at all. [ABSTRACT FROM AUTHOR]

Background: Activin A has been shown to enhance osteoclast activity and its inhibition results in bone growth. The potential role of activin A as a marker of chronic kidney disease-mineral bone disease (CKD-MBD) and its relationship with other markers has not been studied in children with CKD. Methods: A cross sectional study was conducted among 40 children aged 2 to 18 years with CKD (Stage 2 to 5; 10 in each stage) and 40 matched controls. Activin A, cathepsin K, FGF-23, PTH, serum calcium, phosphorous and alkaline phosphatase in both groups were measured and compared. The correlation of activin A and markers of CKD-MBD was studied. A p value of < 0.05 was considered significant. Results: The mean age of children with CKD was 9.30 ± 3.64 years. Mean levels of activin A in cases were 485.55 pg/ml compared to 76.19 pg/ml in controls (p < 0.001). FGF-23 levels in cases were 133.18 pg/ml while in controls it was 6.93 pg/ml (p < 0.001). Mean levels of cathepsin K were also significantly higher in cases as compared to controls. There was a progressive increase in activin A and cathepsin K levels with increasing stage of CKD. Activin A had a significant positive correlation with serum creatinine (r = 0.51; p < 0.001). Conclusions: Activin A levels progressively rise with advancing CKD stage. These findings suggest that activin A can be a potential early marker of CKD-MBD in children. [ABSTRACT FROM AUTHOR]

Endothelial dysfunction (ED) plays a prominent role in the pathogenesis of preeclampsia (PE). There is a need for non-invasive methods to assess endothelial function in preeclamptic patients. In the present study, adropin, autotaxin (ATX), and lysophosphatidic acid (LPA) were evaluated as indicators of ED. Patients diagnosed with PE and healthy pregnant women (n = 42 for each group) were compared. After measuring flow-mediated dilation (FMD), the participants were stratified as ED (+) or ED (−) based on a cut-off value of 6.5%. The PE patients were divided as early/late onset PE and severe/mild PE. Adropin, ATX, and LPA levels were measured, and their relevance to ED was evaluated. Student t, Mann–Whitney U, or ANOVA tests were used for statistics, as appropriate. Adropin levels were diminished in the ED (+) group, whereas ATX and LPA levels were increased. The decrease in adropin levels was more pronounced in severe PE, showing a positive correlation with the FMD. In the logistic regression model, adropin was the only parameter that was an independent variable for the FMD test (P <.001). Adropin measurements in serum may be of value for disease follow-up in patients with PE. [ABSTRACT FROM AUTHOR]

Background: In India, 25%–65% of neonatal deaths are due to sepsis. Since it produces nonspecific symptoms, it is difficult to diagnose and manage. The present study assessed the value of brain natriuretic peptide (BNP) and C-reactive protein (CRP) to predict sepsis along with blood culture. Materials and Methods: Samples were collected from 90 neonates with suspected sepsis, submitted for blood culture, CRP by latex agglutination kit, and BNP by ELISA. Results: Of the 90 cases, blood culture was positive in 25 (28%) cases, BNP in 45 (50%) cases, and CRP in 36 (40%) cases. BNP was positive among 25 (100%) blood culture-positive cases. CRP, BNP, and blood culture were positive in 16 (18%) cases. Conclusion: Although BNP is an equally good marker in predicting sepsis, it is not widely available. Hence, screening by serial CRP along with blood culture alone reinforces the diagnosis. [ABSTRACT FROM AUTHOR]

Aim: Abnormal uterine bleeding (AUB) is a health problem characterized by various symptoms such as heavy and prolonged menstrual bleeding, affecting approximately 30% of female patients both physiologically and psychologically. The objective of this study was to assess serum Elabela (ELA) concentrations in women aged 18 and above diagnosed with functional AUB, and to compare these concentrations with those of healthy women. Material and Method: This prospective case-control study was performed from August 18, 2022 to December 30, 2022. This was a cross-sectional study including 50 women who applied to the gynecology service of Malatya Turgut Özal Training and Research Hospital with complaints of AUB and 50 women without AUB who underwent gynecological examination. The presence of AUB in patients was determined based on clinical examination conducted by a gynecologist and medical records. Demographic and clinical characteristics were recorded. Serum ELA levels were determined by commercial ELISA kit. Results: Serum ELA levels was significantly lower in patients with AUB (581.54±272.25 pg/mL) compared to the healthy group (744.55±300.31 pg/mL, p=0.005). In this study, ELA in patients with AUB showed 98% sensitivity and 80% specificity with a cut off value of 411.41 pg/mL (area under the curve [AUC], 68.1%; p=0.002). Conclusion: Serum ELA levels in patients with AUB were significantly lower than in healthy women. These results show that ELA is a good predictor of the pathophysiological process of AUB. [ABSTRACT FROM AUTHOR]

Background & Objective: Activin A, a protein in the TGF-ß superfamily, plays a crucial role in reproductive regulation by regulating FSH secretion and activating intracellular signaling pathways. Follistatin regulates FSH secretion, affecting follicle genesis and ovulation, playing a crucial role in reproductive processes, especially in ectopic pregnancy and missed abortions. Missed abortions are often caused by genetic factors like chromosomal abnormalities and maternal hormonal imbalances. Evaluated the blood levels of follistatin and activin A in women diagnosed with ectopic pregnancy and missed miscarriage. Research into how follistatin and activin A regulate physiological processes. Materials & Methods: The study included 120 women between the ages of 18 and 45 years, divided into three groups: normal pregnancies (60 women), ectopic pregnancy (30 women), and missed miscarriage (30 women), the gynecology clinic of Baghdad Teaching Hospital for the period from Sept 2023 to Jan 2024. Results: Activin A and follistatin significantly higher in women with ectopic pregnancy and missed abortions than in the control groups. In addition, compared to patients in the missed abortion group, the ectopic group's incidence was significantly lower. Conclusion: Serum Activin A and Follistatin levels can be used as indicators of ectopic pregnancy and missed abortion. Serum FST level at cut-off (>5.24) can be used as a novel biomarker of women with missed abortions. Activin A is involved in the regulation of ovarian follicle development and corpus luteum function in females. [ABSTRACT FROM AUTHOR]

Background & Objective: A competent embryo, receptive endometrium and a series of highly coordinated molecular events between them are all essential for successful implantation. Evaluation of certain molecules which may be used as biomarkers may help to predict pregnancy outcome and detect subtle implantation defect. The present study was conducted with aim to assess the relationship between serum concentrations of adrenomedullin (ADM) and pentraxin3 (PTX3) measured at the day of embryo transfer and successful implantation in assisted reproductive technique cycles. Materials & Methods: This prospective cohort study included 88 frozen embryo transfer (FET) cycles. All patients received sequential oestrogen & progesterone medications. Embryo transfer (with a minimum of one top quality embryo) was scheduled after 4 days (D3 embryo), 6 days (D5 embryo) of progesterone administration. The serum ADM and PTX3 levels were analyzed 1 hour before the embryo transfer (ET) using ELISA kits. A possible association between these two markers levels and embryo implantation was evaluated. Results: Overall, biochemical pregnancy rate was 25% (22/88). Data were then categorized into pregnant (22/88) & non-pregnant (66/88). No significant difference were found between the two groups regarding female age, endometrial thickness, number of oocyte collected, oestradiol level (E2), FSH level, grade and number of embryo transferred (P>0.05). The ADM levels were higher on the day of ET, although was not significant in pregnant group (254.60 pg/ml vs 248.18pg/ml). PXT3 levels (pg/ml) were lower in pregnant compared to non-pregnant group (25.396±11.78 vs 28.431±16.51, P=0.428). Conclusion: Higher ADM and lower PTX3 levels at the day of embro transfer may be associated with successful implantation. [ABSTRACT FROM AUTHOR]

Gastrin is a gastrointestinal peptide hormone that plays an important role in the progression of colorectal cancer (CRC). However, the molecular mechanism remains unclear. In this study, we identified gastrin-related circRNAs via high-throughput sequencing and selected circRNA_0017065 as the research focus. We further studied its specific role and molecular mechanism in the progression of CRC. Knockdown and overexpression of circRNA_0017065 were performed, and the biological function of circRNA_0017065 in CRC progression was studied via in vitro and in vivo functional experiments. The potential downstream target genes were subsequently identified via screening of databases and gene chip data. The expression of circRNA_0017065 in tumour tissues was significantly upregulated compared with that in adjacent normal tissues. In vitro and in vivo functional experiments revealed that the proliferation and migration of CRC cells were significantly suppressed after circRNA_0017065 knockdown, while apoptosis was promoted. After overexpression of circRNA_0017065, the proliferation and migration of CRC cells were significantly promoted, while apoptosis was inhibited. Mechanistic studies revealed that circRNA_0017065 can act as a sponge for miR-3174 and promote CRC progression via the miR-3174/RBFOX2 axis. In general, gastrin-related circRNA_0017065 plays a key role in the occurrence and development of CRC and is expected to be a potential molecular target for the treatment of CRC metastasis. [ABSTRACT FROM AUTHOR]

Background: Acute kidney injury (AKI) significantly increases morbidity and mortality following cardiac surgery, especially in patients with pre-existing renal impairments. N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a marker of cardiac stress and dysfunction, conditions often exacerbated during cardiac surgery and prevalent in chronic kidney disease (CKD) patients. Elevated NT-proBNP levels can indicate underlying cardiac strain, hemodynamic instability and volume overload. This study evaluated the association between perioperative changes in NT-proBNP levels and the incidence of AKI in this particular patient group. Methods: This retrospective study involved patients with impaired renal function (eGFR 15–60 ml/min/1.73 m²) who underwent cardiac surgery from July to December 2022. It analyzed the association between the ratio of preoperative and ICU admittance post-surgery NT-proBNP levels and the development of AKI and AKI stage 2–3, based on KDIGO criteria, using multivariate logistic regression models. Restricted cubic spline analysis assessed non-linear associations between NT-proBNP and endpoints. Subgroup analysis was performed to assess the heterogeneity of the association between NT-proBNP and endpoints in subgroups. Results: Among the 199 participants, 116 developed postoperative AKI and 16 required renal replacement therapy. Patients with AKI showed significantly higher postoperative NT-proBNP levels compared to those without AKI. Decreased baseline eGFR and increased post/preoperative NT-proBNP ratios were associated with higher AKI risk. Specifically, the highest quantile post/preoperative NT-proBNP ratio indicated an approximately seven-fold increase in AKI risk and a ninefold increase in AKI stage 2–3 risk compared to the lowest quantile. The area under the receiver operating characteristic curve for predicting AKI and AKI stage 2–3 using NT-proBNP were 0.63 and 0.71, respectively, demonstrating moderate accuracy. Subgroup analysis demonstrated that the positive association between endpoints and logarithmic transformed post/preoperative NT-proBNP levels was consistently robust in subgroup analyses stratified by age, sex, surgery, CPB application, hypertension, diabetes status and fluid balance. Conclusion: Perioperative NT-proBNP level changes are predictive of postoperative AKI in patients with pre-existing renal deficiencies undergoing cardiac surgery, aiding in risk assessment and patient management. [ABSTRACT FROM AUTHOR]

Background: Patients on maintenance hemodialysis (MHD) have been disproportionately affected by COVID-19. Identifying factors associated with disease severity and viral clearance times can inform better clinical management for this high-risk group. Methods: We retrospectively analyzed clinical and hematological data from 85 COVID-19 positive MHD patients. Disease severity was classified as non-severe (mild/moderate) or severe (severe/critical). Logistic regression was used to evaluate factors associated with disease severity. The time to viral clearance was assessed and correlated with clinical variables. Results: Cardiovascular disease (OR=11.19, 95% CI 2.35–53.38), neutrophilia (OR=1.24, 95% CI 1.01–1.53), and elevated inflammatory markers (procalcitonin and white blood cell count) were independent predictors of severe COVID-19. A prognostic model incorporating these factors showed good discrimination for severity risk (AUC=0.835). The median time to viral clearance was 19 days. Delayed clearance was associated with higher levels of C-reactive protein, troponin, and N-terminal pro-B-type natriuretic peptide. Conclusions: We identified key prognostic factors for COVID-19 severity and characterized the time to viral clearance in MHD patients. These findings can aid in risk stratification and optimize management for this vulnerable population. Further research through multicenter collaborative studies is warranted to validate these results. [ABSTRACT FROM AUTHOR]

Key points Somatostatin, a peptide hormone that activates G‐protein‐coupled receptors, inhibits the secretion of many hormones. This study investigated the mechanisms of this inhibition using amperometry recording of Ca2+‐triggered catecholamine secretion from mouse chromaffin cells. Two distinct stimulation protocols, high‐KCl depolarization and caffeine, were used to trigger exocytosis, and confocal fluorescence imaging was used to monitor the rise in intracellular free Ca2+. Analysis of single‐vesicle fusion events (spikes) resolved the action of somatostatin on fusion pores at different stages. Somatostatin reduced spike frequency, and this reduction was accompanied by prolongation of pre‐spike feet and slowing of spike rise times. This indicates that somatostatin stabilizes initial fusion pores and slows their expansion. This action on the initial fusion pore impacted the release mode to favour kiss‐and‐run over full‐fusion. During a spike the permeability of a fusion pore peaks, declines and then settles into a plateau. Somatostatin had no effect on the plateau, suggesting no influence on late‐stage fusion pores. These actions of somatostatin were indistinguishable between exocytosis triggered by high‐KCl and caffeine, and fluorescence imaging showed that somatostatin had no effect on stimulus‐induced rises in cytosolic Ca2+. Our findings thus demonstrate that the signalling cascades activated by somatostatin target the exocytotic machinery that controls the initial and expanding stages of fusion pores, while having no effect on late‐stage fusion pores. As a result of its stronger inhibition of full‐fusion compared to kiss‐and‐run, somatostatin will preferentially inhibit the secretion of large peptides over the secretion of small catecholamines. Somatostatin inhibits the secretion of various hormones by activating G‐protein‐coupled receptors. In this study, we used amperometry to investigate the mechanism by which somatostatin inhibits catecholamine release from mouse chromaffin cells. Somatostatin increased pre‐spike foot lifetime and slowed fusion pore expansion. Somatostatin inhibited full‐fusion more strongly than kiss‐and‐run. Our results suggest that the initial fusion pore is the target of somatostatin‐mediated regulation of hormone release. The stronger inhibition of full‐fusion by somatostatin will result in preferential inhibition of peptide release. [ABSTRACT FROM AUTHOR]

Iron is an essential element for human health. In humans, dysregulated iron homeostasis can result in a variety of disorders and the development of cancers. Enhanced uptake, redistribution, and retention of iron in cancer cells have been suggested as an "iron addiction" pattern in cancer cells. This increased iron in cancer cells positively correlates with rapid tumor growth and the epithelial-to-mesenchymal transition, which forms the basis for tumor metastasis. However, the source of iron and the mechanisms cancer cells adopt to actively acquire iron is not well understood. In the present study, we report, for the first time, that the peptide hormone, prolactin, exhibits a novel function in regulating iron distribution, on top of its well-known pro-lactating role. When stimulated by prolactin, breast cancer cells increase CD44, a surface receptor mediating the endocytosis of hyaluronate-bound iron, resulting in the accumulation of iron in cancer cells. In contrast, macrophages, when treated by prolactin, express more ferroportin, the only iron exporter in cells, giving rise to net iron output. Interestingly, when co-culturing macrophages with pre-stained labile iron pools and cancer cells without any iron staining, in an iron free condition, we demonstrate direct iron flow from macrophages to cancer cells. As macrophages are one of the major iron-storage cells and it is known that macrophages infiltrate tumors and facilitate their progression, our work therefore presents a novel regulatory role of prolactin to drive iron flow, which provides new information on fine-tuning immune responses in tumor microenvironment and could potentially benefit the development of novel therapeutics. [ABSTRACT FROM AUTHOR]

We investigated the effects of tobacco smoke exposure and abnormal body weight on selected peptide hormones and their association with metabolic and hormonal disorders in women with polycystic ovary syndrome (PCOS). The study group included 88 women with PCOS and 28 women without the disease. In women with PCOS, chemerin, lipocalin, and apelin concentrations were influenced by overweight and obesity status, with the highest concentrations observed in those with a body mass index (BMI) ≥ 30.0. Exposure to tobacco smoke significantly increased only lipocalin-2 concentration. The disease itself did not affect the concentrations of chemerin, lipocalin, and apelin. Additionally, we found a positive correlation between chemerin concentration and fasting glucose, fasting insulin, and triglycerides levels, while a negative correlation was observed with high-density lipoprotein (HDL-C) concentration. In the smoking subgroup, chemerin concentration was positively correlated with free testosterone concentration and the free androgen index and negatively associated with sex hormone-binding globulin concentration. Our findings indicate that abnormal body weight has a stronger impact than tobacco smoke exposure on metabolic and hormonal disorders in women with PCOS, highlighting the important role of weight control in such individuals. However, smoking appears to be an additional factor that intensifies hormonal disorders associated with adipose tissue. [ABSTRACT FROM AUTHOR]

Group-based trajectory modeling (GBTM) allows the trajectory analyses of repeated N-terminal pro-brain natriuretic peptide (NT-proBNP) measurements during follow-up visits of pulmonary artery hypertension associated with connective tissue disease (CTD-PAH) patients. This study aimed to (1) identify trajectories of NT-proBNP changing over time, (2) explore the association between NT-proBNP trajectories and prognosis, and (3) explore the effects of baseline clinical characteristics on NT-proBNP trajectories. A retrospective, single-centred, observational study was performed on 52 CTD-PAH patients who had undergone at least three follow-up visits within 1 year from baseline. Four NT-proBNP trajectories were identified using GBTM: low stability (n = 15, 28.85%), early remission (remission within 3 months) (n = 20, 38.46%), delayed remission (remission after 6 or 9 months) (n = 11, 21.15%), and high stability (n = 6, 11.54%). The low-stability and early-remission trajectories were related to a similar positive prognosis, while the delayed-remission and high-stability trajectories were associated with a gradually worsening prognosis (p = 0.000). Intensive CTD immunotherapy (corticosteroids plus immunosuppressants) was the only factor that remained significant after least absolute shrinkage and selection operator regression and multivariate logistic regression, and was independently associated with a lower risk NT-proBNP trajectory (p = 0.048, odds ratio = 0.027, 95% confidence interval: 0.001–0.963), which preliminarily indicated a benefit of CTD-PAH patients undergoing intensive CTD immunotherapy. [ABSTRACT FROM AUTHOR]

Introduction: Early identification of patients with sepsis at high risk of death remains a challenge, and whether brain natriuretic peptide (BNP) or N-terminal pro-B-type natriuretic peptide (NT-proBNP) has a prognostic effect on patients with sepsis is controversial. Here, we clarified the prognostic value of BNP and NT-proBNP and sought to establish suitable cutoff values and intervals. Methods: We searched five databases to identify studies that met the inclusion criteria. The primary outcomes were the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), area under the curve (AUC), and corresponding 95% credible interval (95% CI) of BNP and NT-proBNP. The secondary outcomes were the sensitivity and specificity of BNP or NT-proBNP in subgroup analyses. Results: Forty-seven studies were included in our meta-analysis. The pooled sensitivity of NT-proBNP (0.77 [0.68, 0.84]) was weaker than that of BNP (0.82 [0.76, 0.87]), the pooled specificity of NT-proBNP (0.70 [0.60, 0.77]) was less than that of BNP (0.77 [0.71, 0.82]), and the AUC of BNP (0.87 [0.83–0.89]) was greater than that of NT-proBNP (0.80 (0.76–0.83]). The results of the subgroup analysis showed that the cutoff range of 400–800 pg/mL for BNP had high sensitivity (0.86 [0.74–0.98]) and specificity (0.87 [0.81–0.93]) and was probably the most appropriate cutoff range. Conclusions: Elevated levels of BNP and NT-proBNP were significantly related to the mortality of patients with sepsis and had a moderate prognostic value in predicting the mortality of patients with sepsis. In addition, our meta-analysis preliminarily established appropriate cutoff values for BNP and NT-proBNP. [ABSTRACT FROM AUTHOR]

Irisin was identified as a peptide hormone in 2012. The most important known physiological effect of irisin is that it activates uncoupling protein 1 and converts white adipose tissue to brown adipose tissue. Due to this effect of irisin on adipose tissue, it was thought that it may be closely related to obesity, feeding behavior and energy expenditure, and interest in research in this direction has increased. Later studies revealed that irisin, beyond its known effects, also influences the reproductive, nervous, cardiovascular, and excretory systems. Recent studies have determined that irisin has anti-oxidant, anti-inflammatory and anti-apoptotic properties, and it has been reported that pathologies such as obesity, endocrine and metabolic diseases, Alzheimer's disease, chronic kidney disease, cardiovascular diseases, atherosclerosis and cancer may be associated with changes irisin levels. The fact that irisin is expressed in different tissues other than muscle and fat tissue and exhibits autocrine and endocrine functions, as well as being expressed in different regions of the brain and participating in neuroendocrine processes in these regions, brings to mind that irisin may be a new neuroendocrine factor. In this review, we present information that will constitute evidence that irisin is a real neuroendocrine factor. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore the clinical efficacy and safety of the combination of thymopeptide enteric-coated tablets and Compound Kuwei Huoxue Formula in the treatment of oral lichen planus (OLP). Using a random number table, the patients were divided into a study group and a control group after registration and enrollment. There was no significant difference in the general data comparison between the two groups (P > 0.05). After treatment, the number of cured patients in the study group was higher than that in the control group, and the number of ineffective cases was lower than that in the control group. The total cure rate in the study group was higher than that in the control group (P < 0.05). The levels of inflammatory factors interleukin-4, interleukin-6, and interferon-γ in the study group. Based on the practical clinical considerations, the treatment regimen of oral immunomodulator-thymopeptide enteric-coated tablets combined with Compound Kuwei Huoxue Formula emphasizes enhancing the immune function of the body and adopting the principle of clearing heat and detoxification in traditional Chinese medicine to achieve the goal of treating the root cause. This comprehensive treatment approach has achieved good clinical efficacy, providing new ideas and methods for the treatment of OLP that are worth promoting. [ABSTRACT FROM AUTHOR]