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The effects of collagen peptide supplementation on appetite and post-exercise energy intake in females: a randomised controlled trial.
Br J Nutr
Kirsty M Reynolds, Emily J Hansell, Josh Thorley +8 more
This study examined whether supplementation with collagen peptides (CP) affects appetite and post-exercise energy intake in healthy active females. In this randomised, double-blind cross-over study, fifteen healthy females (23 (sd 3) years) consumed 15 g/d of CP or a taste matched non-energy control (CON) for 7 d. On day 7, participants cycled for 45 min at ∼55 % Wmax, before consuming the final supplement. Sixty-min post supplementation an ad libitum meal was provided, and energy intake recorded. Subjective appetite sensations were measured daily for 6 d (pre- and 30 min post-supplement) and pre (0 min) to 280 min post-exercise on day 7. Blood glucose and hormone concentrations (total ghrelin, glucagon-like peptide-1 (GLP-1), and peptide YY (PYY), cholecystokinin (CCK), dipeptidyl peptidase-4 (sDPP-4), leptin, and insulin) were measured fasted at baseline (day 0), then pre-breakfast (0 min), post-exercise (100 min), post-supplement (115, 130, 145, 160 min) and post-meal (220, 280 min) on day 7. Ad libitum energy intake was ∼10 % (∼41 kcal) lower in the CP trial (P = 0·037). There was no difference in gastrointestinal symptoms or subjective appetite sensations throughout the trial (P ≥ 0·412). Total plasma GLP-1 (AUC, CON: 6369 (sd 2330); CP: 9064 (sd 3021) pmol/l; P < 0·001) and insulin (+80 % at peak) were higher after CP (P < 0·001). Plasma ghrelin and leptin were lower in CP (condition effect; P ≤ 0·032). PYY, CCK and glucose were not different between CP and placebo (P ≥ 0·100). CP supplementation following exercise increased GLP-1 and insulin concentrations and reduced ad libitum energy intake at a subsequent meal in physically active females.
Early Use of Innovative Biomarkers Such as Mid-Regional Pro-Adrenomedullin and SeptiCyte® RAPID in Post-Cardiac Surgery Patients: Pilot Case Series.
Int J Mol Sci
Chiara Risso, Lorenzo Vay, Francesca Sciascia +5 more
Prognostic uncertainty and missed diagnoses of sepsis remain frequent after cardiopulmonary bypass (CPB) surgery, where systemic inflammatory response (SIRS) arises from surgical trauma, blood activation in the extracorporeal circuit, ischemia/reperfusion injury, and endotoxin release. Among innovative biomarkers, pro-adrenomedullin (pro-ADM), particularly its stable fragment mid-regional pro-adrenomedullin (MR-proADM), has shown promise for detecting endothelial dysfunction and predicting organ failure in sepsis. SeptiCyte® RAPID (Seattle, WA, USA) also represents a novel diagnostic tool that assesses the host immune response by quantifying PLA2G7 and PLAC8 gene expression in whole blood, offering potential for early differentiation between sepsis and sterile inflammation. We analyzed traditional and innovative biomarkers within 24 h post-CPB in a pilot group of patients admitted to the cardiac Intensive Care Unit of the "Città della Salute e della Scienza" University Hospital (Turin, Italy) between June and November 2023. Data from the following 14 patients were collected: 7 undergoing surgery for infective endocarditis (IE, Group 1) and 7 having standard elective cardiac surgery (Group 2). Procalcitonin (PCT), lactate, and pro-ADM increased in Group 1 but not in Group 2. SeptiCyte® RAPID showed a moderate, borderline increase in Group 1. The innovative biomarkers had a good performance in patients exhibiting signs of organ dysfunction and in subjects demonstrating at least cardiovascular and/or pulmonary damage and under vasopressor and inotropic support. Although limited by the small sample, our preliminary data suggest no biomarker alterations in patients with standard elective cardiac surgery, unlike in those with IE.
Steatotic liver disease and cancer: from pathogenesis to therapeutic targets.
eGastroenterology
Zhihong Yang, Zhenjie Liu, Wanqing Liu +1 more
As environmental exposomes are changing with time, so are liver diseases around the globe. Due to an increasing prevalence of overnutrition and sedentary lifestyle in the global population, metabolic dysfunction-associated steatotic liver disease (MASLD) and steatohepatitis have been increasing steadily in the past decades. Alcohol consumption is another common risk factor for liver diseases such as alcohol-associated liver disease or hepatitis. For both alcohol-associated and metabolic dysfunction-associated liver diseases, hepatocyte injuries are among the early events during the development of steatotic liver disease (SLD). Hepatic inflammation and fibrosis ensue with recurring hepatic damages owing to immune responses from multiple immune cell types, particularly neutrophils, Kupffer cells and monocyte-derived macrophages in response to damage-associated and pathogen-associated molecular patterns, and extracellular matrix production predominantly from hepatic stellate cells. Both environmental and genetic factors contribute to the SLD pathogenesis. Common environmental risk factors include obesity, type 2 diabetes mellitus, unhealthy diets, sedentary lifestyle and excessive alcohol consumption. Numerous genome-wide association studies have identified multiple genetic variants associated with key traits of SLD, including patatin-like phospholipase domain containing 3 rs738409, transmembrane 6 superfamily member 2 rs58542926, membrane bound O-acyltransferase domain containing 7 rs641738 and hydroxysteroid 17 beta-dehydrogenase 13 rs72613567. Cirrhosis and liver cancer are common late-stage developments of various chronic liver diseases; however, there are pathological differences according to disease aetiologies. Therefore, preventive and therapeutic intervention strategies should align with the underlying causal and modifiable factors. Currently, multiple therapeutics have been developed or approved for treatment of SLD, including thyroid hormone receptor β agonists, glucagon-like peptide 1 receptor agonists and fibroblast growth factor 21 analogues. The concept of this review was motivated and inspired by the Seventh Annual Symposium of Chinese American Liver Society held in San Diego, California, USA on 13-14 November 2024.
Tirzepatide, a dual GLP-1 and GIP receptor agonist, promotes bone loss in obese mice via gut microbial-related metabolites.
J Orthop Translat
Ning Chen, Mengdan Zhang, Baohong Shi +10 more
As a novel dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1) receptor agonist, Tirzepatide (TZP) is a recently approved medication for treating type 2 diabetes mellitus (T2DM) and obesity; however, the effect of TZP in bone remodeling remains unclear.
Insulin-like growth factor-I and symptoms of acromegaly according to time since somatostatin receptor ligand injection.
Eur J Endocrinol
Ilan Remba-Shapiro, Júnia R O L Schweizer, Alberto Moscona-Nissan +9 more
Somatostatin receptor ligands (SRLs) are the mainstay of pharmacotherapy for acromegaly. Patients report symptoms toward the end of the injection cycle. However, the correlation between insulin-like growth factor-I (IGF-I) and patient-reported outcomes (PROMs) has not been evaluated in this context.
Acute Exercise Effects on Appetite and Energy Intake in People Living With Overweight and Obesity: A Systematic Review and Meta-Analysis.
Int J Sport Nutr Exerc Metab
Nan Li, Min Wu, Yanchun Li
Overweight and obesity are associated with dysregulation of appetite-related hormones and altered energy intake. Exercise has been proposed as a strategy to modulate appetite and support weight management. A comprehensive search of databases, including Web of Science, PubMed, Scopus, Google Scholar, ScienceDirect, Academic Search Premier, and EBSCOHost, identified 19 studies (34 trials) for inclusion. Using a random-effects model, we calculated effect sizes (ES) for hormone concentration, appetite perception, and energy intake. Acute exercise exerted a moderate suppressive effect on acylated ghrelin (ES = -0.73) and a moderate, nonsignificant effect on insulin (ES = -0.55). A large but nonsignificant increase was observed for glucagon-like peptide-1 (ES = 3.96), while peptide YY showed a small, nonsignificant increase (ES = 0.24). Exercise significantly reduced hunger (ES = -0.35) and prospective food consumption (ES = -0.26), with minimal effects on fullness (ES = 0.16) and satiety (ES = 0.15). Significant reductions were found in both relative (ES = -0.54) and absolute energy intake (ES = -0.19). Exercise may be an effective short-term intervention for reducing appetite and energy intake among people living with overweight and obesity. Registration: PROSPERO CRD42024623903.
Semax peptide targets the μ opioid receptor gene Oprm1 to promote deubiquitination and functional recovery after spinal cord injury in female mice.
Br J Pharmacol
Rongjie Liu, Yituo Chen, Haosheng Huang +12 more
Lysosomal membrane permeabilization (LMP) is exacerbated following spinal cord injury (SCI), leading to increased neuronal cell death. Ubiquitination may affect LMP by regulating the stability and functionality of lysosomal membranes. Semax, a synthetic heptapeptide, comprising the ACTH (4-7) fragment and a C-terminal Pro-Gly-Pro tripeptide, exhibits neuroprotective properties and improves cognitive function. Given the key roles of LMP and ubiquitination in SCI pathophysiology, this study investigated how Semax could modulate these pathways to affect functional recovery following SCI.
Dose-response effects of exogenous oxytocin on social cognition: A systematic review.
Neurosci Biobehav Rev
Simon Barton, Annika Pruin, Janna Schulze +3 more
Oxytocin, a neuropeptide known for its role in social bonding, has garnered considerable attention for its potential to enhance social cognition in humans. Intranasal administration of oxytocin is the standard method in exogenous oxytocin research. This systematic review critically examines the effects of exogenously administered oxytocin on three core components of social cognition: emotion recognition, empathy, and interpersonal trust. By comparing findings across studies using intranasal oxytocin doses ranging from 1 IU to 48 IU in healthy adult humans, we evaluate evidence for a potential dose-response relationship. The majority of studies administered a standard dose of 24 IU and generally reported significant improvements in emotion recognition, empathy, and trust. However, divergent findings at this dose have also been observed. Evidence for both lower and higher doses remains mixed. Much of the support for the Inverted-U Curve hypothesis - suggesting that oxytocin's effects follow a nonlinear trajectory with optimal outcomes at moderate doses - comes from studies lacking direct dose comparisons. Furthermore, the effects of oxytocin on social cognition appear to be strongly moderated by individual and contextual factors, raising questions about the generalizability of the Inverted-U model. Additional research is necessary to clarify the conditions under which dose-dependent effects occur.
Melatonin suppresses the seasonal estrus in female giant pandas.
Gen Comp Endocrinol
He Huang, Rong Hou, David C Kersey +7 more
In mammals, the pineal gland secretes melatonin, which serves as a crucial signal for interpreting photoperiod cues. As a seasonal breeder, the giant panda typically mates during the spring. To fully elucidate melatonin's influence on the seasonal estrus of female giant pandas, we conducted an in-depth analysis of urinary hormones. First, we found that urinary melatonin and gonadotropin-releasing hormone (GnRH) levels exhibit distinct seasonal variations over the annual cycle. From January to April, melatonin levels decline sharply from their annual peak, while GnRH levels rise rapidly and remain elevated throughout February, March, and April, precisely corresponding to the giant panda breeding season. Second, during female estrus, the estrogen metabolites peak occurs near the time when melatonin levels drop to their lowest values, and an inverse correlation between melatonin and estrogen metabolites persists both before and after the estrogen metabolites peak. Our analysis of urinary hormones revealed that melatonin exerts a significant suppressive effect on urinary GnRH and estrogen metabolites production prior to the onset of the seasonal estrus in giant pandas. Given the multipotent differentiation capacity of mesenchymal stem cells, we selected cultured giant panda umbilical cord mesenchymal stem cells (UC-MSCs) as an in vitro model for further study. Initially, we characterized the expression of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in UC-MSCs following GnRH stimulation. Notably, these cells exhibited pituitary-like functional properties, including responsiveness to GnRH and expression of FSH and LH genes, making them suitable for modeling melatonin's effects. Subsequent experiments demonstrated that melatonin suppresses GnRH-induced LH and FSH mRNA expression in UC-MSCs in a dose-dependent manner and higher concentrations of melatonin were particularly effective. Collectively, our study not only elucidates the regulatory effects of melatonin on the seasonal estrous cycle of female giant pandas but also offers valuable new perspectives. These insights can potentially guide the development of conservation strategies for this endangered species, facilitating more targeted and effective efforts to safeguard its population.
Regulation of Melanogenesis in Skin Epidermal Keratinocytes via Activation of α7 Nicotinic Acetylcholine Receptor on the Expression of α-Melanocyte-Stimulating Hormone.
FASEB J
Maggie Suisui Guo, Xiaoyang Wang, Yingjie Xia +5 more
UV irradiation stimulates the production of pro-opiomelanocortin (POMC) and its derived peptides, for example, α-melanocyte stimulating hormone (α-MSH), from keratinocytes that subsequently stimulate melanin production in melanocytes. The idea of "skin synapse" describes the interplay between keratinocytes and melanocytes being modulated by cholinergic signaling, in which acetylcholine (ACh) release is induced by UV irradiation, regulating the process of pigmentation. ObjectiveHere, the role of the cholinergic system in regulating α-MSH production in keratinocytes during UV-induced skin pigmentation was identified. α7 Nicotinic acetylcholine receptor (nAChR) agonists and antagonists, Ca2+ chelator BAPTA-AM, and α7 nAChR shRNA were applied onto HaCaT keratinocytes to evaluate the expression of POMC and production of α-MSH following UVB induction. Moreover, the conditioned medium collected from the treated HaCaT keratinocytes was added to cultured B16F10 melanoma cells to assess melanogenesis. Inhibiting α7 nAChR by its antagonist, or Ca2+ influx by Ca2+ chelator, suppressed the UVB-induced POMC expression and α-MSH production in cultured keratinocytes. Genetic silencing α7 nAChR expression hindered the UVB-induced POMC expression. Besides, the conditioned medium collected from keratinocytes being treated with α7 nAChR antagonist and UVB downregulated melanogenesis, as implied by the reduced expression of melanogenic enzymes, indicating the suppressing effect of α7 nAChR antagonist on the production of α-MSH in keratinocytes. The result suggests that α7 nAChR mediates the regulation of melanogenesis through the modulation of UVB-induced POMC transcription and α-MSH production in keratinocytes.
3D Printing of Chitosan Scaffolds and Films with Varying Roughness for Cultivation of Human Retinal Progenitor Cells.
ACS Omega
Amalie Solberg, Natalia Robles-Anda, Eva Pasquier +4 more
Chitosan was used for three-dimensional (3D) printing of films and well-resolved scaffolds. Three different molecular weights with a comparable degree of de-N-acetylation were studied for 3D printing; inks were characterized using rheology, and the resulting two-dimensional (2D) and 3D architectures were characterized by scanning electron microscopy (SEM). Printing and fixation were optimized for retention of shape fidelity. The films and scaffolds were functionalized with a short peptide containing the integrin-binding arginylglycylaspartic acid (Arg-Gly-Asp, RGD) sequence using a postprinting grafting approach. The 2D films and 3D scaffolds prepared were studied as support materials for human retinal progenitor cells (hRPCs), and the properties of native and RGD-modified chitosan were compared as support materials for hRPCs. The adhesion and proliferation of hRPCs were studied over a period of 6 or 18 days, and Matrigel was used as a positive control. Grafting with the RGD-containing peptide generally improved the biocompatibility of the materials. When comparing films with varying surface roughness resulting from the method used for drying, the cellular response differed significantly. The best performing material was air-dried chitosan films, which resulted in the formation of axons and larger cell clusters with observable live cells after 18 days of culture time. This work demonstrates effective methods for the preparation of 3D printed architectures and the promise of these materials for cell therapies and bioengineering applications.
Exploring the effects of high protein versus high fat snacks on satiety, gut hormones and insulin secretion in women with overweight and obesity: A randomized clinical trial.
Obes Pillars
Nahla Al-Bayyari, Maysoon Alhameedy, Razan Omoush +1 more
Nuts generally blunt the postprandial increases in glucose levels and increase satiety, while yogurt studies yield inconclusive results regarding post-meal hunger. This study investigated the effects of high-protein, and high-fat snacks, specifically Greek yogurt, and peanuts, on satiety, gut hormones, and insulin secretion in women with overweight and obesity. The hypothesis posited that peanuts would exhibit a more beneficial impact on satiety, gut hormones, and insulin levels compared to Greek yogurt.
Effect of carperitide on mortality and ANP levels in acute heart failure: A systematic review and meta-analysis.
Am Heart J Plus
Allahdad Khan, Shree Rath, Saad Ahmed Waqas +7 more
Acute heart failure (AHF) is a common and severe condition associated with high morbidity and mortality. Carperitide, a recombinant human atrial natriuretic peptide, has been widely used in Japan for managing AHF. However, its effectiveness in improving clinical outcomes such as mortality rates remains unclear, with conflicting evidence from studies.
Prognostic Impact of Fibroblast Growth Factor 21 in Patients With Heart Failure.
Circ Rep
Hiroaki Sunaga, Kuniko Yoshida, Kazuki Kagami +10 more
Systemic and cardiac metabolic disorders play a key role in patients with heart failure (HF). Fibroblast growth factor 21 (FGF21) is mainly secreted from the liver and has various effects on cardiomyocytes, including protection against oxidative stress, cardiac hypertrophy, and inflammation. However, the pathophysiologic and prognostic impact of FGF21 remains unknown.
Central pramlintide administration potently suppresses operant responding for sucrose and locomotor activity in male rats.
Physiol Behav
Katherine A Kern, Adrianne M DiBrog, Emily Demieri +3 more
Amylin is a feeding-suppressive hormone which acts centrally in the control of energy balance. Some evidence suggests it reduces motivation for food rewards. Pramlintide is a synthetic amylin analog that is used clinically in the treatment of diabetes, and it also reduces feeding and weight gain. However, the mechanisms behind these pramlintide-induced reductions in feeding are unclear. Here we tested the hypothesis that pramlintide would decrease motivation for a palatable food, sucrose pellets. Results show that peripheral (IP) pramlintide had no effect on progressive ratio responding for sucrose pellets. In contrast, intracerebroventricular (ICV) pramlintide reduced active lever pressing, reinforcers earned, and breakpoint for sucrose, even at lower doses subthreshold for effects on 24 h chow intake and body weight change. However, lever pressing behavior was completely abolished for many rats, raising concern for unexpected motor effects. To test whether central pramlintide impacted locomotor activity, we conducted an open field study and found that ICV pramlintide significantly reduced distance traveled at several timepoints, suggesting suppressed locomotor activity. Overall, our results suggest that peripheral pramlintide does not affect motivation for sucrose, and that although central pramlintide does reduce outcomes assessing motivation, this may be confounded by a concurrent reduction in locomotor activity.
Is the renin-angiotensin system a friend or foe in neurological diseases? Unveiling its role and therapeutic potential.
Ageing Res Rev
Pratyush Porel, Garry Hunjan, Shamsher Singh +1 more
The renin-angiotensin system (RAS), an important regulator of body fluid and cardiovascular homeostasis, is gradually implicated in the pathogenesis of neurological diseases due to its dysregulation. In addition to their traditional functions, components of the RAS, especially angiotensin-II (Ang-II), enhance neuroinflammation, oxidative stress, and neuronal injury. Ang-II exacerbates blood-brain barrier (BBB) disruption, promotes glial activation, and contributes to neurodegeneration via the Angiotensin type 1 (AT1) receptor (AT1R) and causes neurological diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), multiple sclerosis (MS), Huntington's disease (HD), epilepsy, depression, and anxiety. The angiotensin (1-7) axis mediated by the Mas receptor appears to be neuroprotective, however, as it reverses the negative effects of Ang-II. In experimental models and clinical trials, blocking RAS specifically by angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) has demonstrated promise in reducing neuroinflammation and neuronal damage, especially in stroke and neurodegenerative diseases. In the current era of research, neuropharmacologists have new optimism due to emerging evidence of the promising potential of RAS-modulating drugs, such as ARBs and ACEIs, in the treatment of various neurological diseases. Since RAS imbalance causes neuroinflammation, neuronal damage, and cognitive decline in conditions including AD, PD, and MS, these drugs may offer a new treatment approach. In the current era of neuropharmacology, this technique is novel since it enables more targeted therapies to address the root causes of neurodegeneration. This review explores the molecular pathways of RAS dysregulation in various neurological diseases, highlighting its therapeutic potential and paving the way for future treatment strategies.
Orexin Deficiency in Narcolepsy: Molecular Mechanisms, Clinical Phenotypes, and Emerging Therapeutic Frontiers.
Brain Behav
Rameesha Rauf, Salwa Asif, Abdallah AlSaafeen +7 more
Narcolepsy Type 1 (NT1) is a chronic neurological disorder characterized by excessive daytime sleepiness (EDS), cataplexy, and REM intrusions, caused by a deficiency of orexin (hypocretin), a hypothalamic neuropeptide essential for arousal, REM sleep regulation, metabolism, and emotional stability. This review synthesizes and critically analyzes the pathophysiological, clinical, and therapeutic dimensions of orexin deficiency in narcolepsy, with particular emphasis on recent advances from 2023 to 2025.
Reproductive dysfunction in hemodialysis: endocrine mechanisms, clinical features, and therapeutic approaches.
Ren Fail
Wei Gou, Cheng Xue, Fanzhou Zeng +2 more
Reproductive dysfunction is a near-universal and debilitating complication in patients on maintenance hemodialysis, profoundly impacting quality of life. The core patho-physiology is a 'dual-hit' endocrine collapse, where the uremic milieu causes both central suppression of the hypothalamic-pituitary-gonadal (HPG) axis and peripheral gonadal resistance. In men, this manifests as hypogonadism, with erectile dysfunction serving as a critical sentinel marker for systemic vascular disease. In women, it results in a reversible menopause-like state characterized by anovulation and infertility. While conventional hemodialysis is insufficient to correct these derangements, practical therapeutic strategies can mitigate them. Intensified regimens like nocturnal hemo-dialysis can partially restore fertility and dramatically improve pregnancy outcomes. Targeted pharmacological interventions, including phosphodiesterase-5 inhibitors and hormone replacement therapy, are also effective for specific indications. Kidney transplantation offers the best chance of restoring normal endocrine function. Future directions include novel therapeutics targeting the kisspeptin system and the development of wearable artificial kidneys to provide continuous uremic clearance. This review provides a clinically focused overview of the endocrine mechanisms, features, and management of reproductive dysfunction in hemodialysis.
Development of a genetically encoded melanocortin sensor for high sensitivity in vivo imaging.
Mol Metab
Yoon Namkung, Tal Slutzki, Joao Pedroso +4 more
The central melanocortin system, composed of peptides derived from pro-opiomelanocortin (POMC) such as the melanocyte-stimulating hormones (α-, β-, γ-MSH) and melanocortin 4 receptors (MC4R), along with the agouti-related protein (AgRP), plays a pivotal role in controlling energy balance. To elucidate the dynamic role of α-MSH release in regulating appetite, specific, sensitive, and spatiotemporally resolved genetic sensors are required.
Strategic Design of Triple GLP-1R/GCGR/GIPR Agonists with Varied Receptor Potency: Achieving Comparable Glycemic and Weight Reduction Effects.
J Med Chem
Shuang Wang, Yun Liu, Zhiming Yan +8 more
Triple activation of the glucagon-like peptide 1 receptor (GLP-1R), the GIP receptor (GIPR), and the glucagon receptor (GCGR) is an innovative strategy for treating obesity and diabetes. We report the rational design of triple GLP-1R/GCGR/GIPR agonists, featuring potent GLP-1R and GCGR activity with weaker GIPR activation. Using sequence analysis, molecular dynamics simulations, docking, and amino acid optimization, we developed xGLP-1-based triagonists, with xGLP/GCG/GIP-32 exhibiting a unique activation profile. It shows superior weight loss effects compared to tirzepatide and similar metabolic efficacy to retatrutide, despite significantly less potent GIPR activity. Preliminary mechanistic studies revealed that xGLP/GCG/GIP-32 exhibits biased agonism toward the GIPR and GCGR. These activity data suggest it may not be imperative to focus solely on potent activation of all three receptors. Especially for triple agonists with receptor-biased agonism, there may be room to explore optimal receptor activation ratios.