Search Results (200)

Background/Objectives: Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with limited therapeutic options, a high mortality rate, and poor overall survival, necessitating the development of new therapeutic and diagnostic strategies. This study investigated the potential of plasma-derived small extracellular vesicles (sEVs) as a source of molecular biomarkers associated with the treatment response. Methods: Plasma samples were obtained from patients with locally advanced and borderline resectable PDAC at baseline and following neoadjuvant chemotherapy, either FOLFIRINOX (5-FU [fluorouracil], leucovorin, oxaliplatin, and irinotecan) or GEM-ABRAX ( gemcitabine plus nab-paclitaxel), followed by stereotactic body radiation therapy (SBRT). sEVs were isolated from plasma at baseline, after neoadjuvant chemotherapy, and following SBRT, and were characterized by nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM), nano-flow cytometry, and real-time PCR (RT-PCR). Results: The isolated sEVs exhibited an average size of <200 nm, expressed canonical exosome markers (CD63 and CD9), and exhibited pancreatic cancer (PanC)-associated markers, including cholecystokinin A receptor (CCK-AR) and carbohydrate antigen 19-9 (CA19-9). The sEV cargo included several PanC-associated microRNAs (miRNAs). Notably, the expression profiles of these miRNAs demonstrated interpatient variability, though a subset of miRNAs showed statistically significant changes following treatment. Conclusions: These findings support the feasibility of sEV isolation and molecular profiling from patient plasma and warrant further investigation as a potential source of biomarkers in pancreatic cancer. Full article

Background/Objectives: Umami peptides enhance flavor and contribute to appetite regulation (satiety) and metabolic health. By signaling to the orbitofrontal cortex, umami has been shown to improve cognitive function in Alzheimer’s disease dementia. This taste boosts the immune system and induces saliva secretion. However, the molecular mechanisms linking umami peptides to systemic physiology remain poorly understood. This study provides the first integrated analysis of neurological, immunological, and endocrinological pathways activated by umami peptides. Methods: Novel umami peptides were identified using machine-learning and deep-learning analyses from a library of marine-derived bioactive peptides. T1R1-T1R3 heterodimer is the dominant receptor for umami taste transmission in humans, expressed on taste cells, intestinal cells, and hypothalamic tanycytes. Molecular docking confirmed the binding of novel ligands to the T1R1-T1R3 receptor complex. New candidates and experimentally validated umami peptides, identified by sensomics approaches from tauco, chicken soup, pufferfish, and dry-cured ham, were analyzed using gene ontology. Results: The functional enrichment analysis revealed crosstalk among key signaling processes, including glutamatergic and opioidergic pathways. In addition to the role of µ1 opioid receptor (OPRM1), hub gene intersections highlight cholecystokinin (CCK), glucagon-like peptide 1 (GLP-1), and the anorexigenic pro-opiomelanocortin (POMC) neurons as potential regulators of the gut–brain axis in satiety signaling. Chemokine-encoding genes, melanin-concentrating hormone (MCH), oxytocin (OXT), and neurotensin (NTS) were other key target genes. Conclusions: The identified targets reveal the coordinated crosstalk between peripheral and central umami signaling that may contribute to the regulation of feeding behavior, satiety, cognition, memory, learning, and immune function. These network-based insights generate hypotheses and guide the design of nutritional and drug-like effectors for metabolic and cognitive health. Full article

Background: We investigated whether a water extract of Lilii bulbus (Lilium lancifolium Thunberg; WELB) could modulate inhibitory synaptic organization in a mouse model of pentylenetetrazol (PTZ)-induced kindling. Methods: Starting 14 days prior to the initial PTZ challenge, WELB (500 mg/kg) was delivered via oral gavage once daily. This treatment regimen was maintained for a total of 40 days, spanning the entire period until the animals reached the fully kindled state. Results: Behavioral assessments revealed that WELB treatment significantly reduced seizure severity and Racine scores, prolonged the latency to clonic seizures, and shortened seizure duration, demonstrating potent anticonvulsant activity. Two-photon calcium imaging further showed that WELB markedly suppressed PTZ-induced neuronal hyperexcitability in the posterior parietal cortex, accompanied by decreased expression of neuronal activation markers, including c-fos, phosphorylated-calcium/calmodulin-dependent protein kinase IIα (p-CaMKIIα), and N-methyl-D-aspartate receptor 1 (NR1). In the hippocampus, WELB modulated the expression of GABAergic interneuron markers [glutamate decarboxylase 67 (GAD67), vesicular GABA transporter (VGAT), parvalbumin (PV), somatostatin (SOM)] and upregulated GABAergic gene transcripts [GABA-A receptor α1 subunit (Gabra1), GABA-A receptor α2 subunit (Gabra2), GABA transporter 1 (Gat1), GABA transporter 3 (Gat3), PV, SOM, cholecystokinin (CCK)] that were downregulated by PTZ kindling. Moreover, WELB enhanced the expression of GABAergic synaptic organization-related proteins (gephyrin, collybistin, neurexin-1β, neuroligin-2, and neuropilin-2), indicating its regulatory effect on inhibitory synaptic integrity. Conclusions: Collectively, these findings suggest that WELB may exert its anticonvulsant effects by functionally remodeling GABAergic synaptic organization-related factors, thereby restoring inhibitory circuit integrity and providing a mechanism-based therapeutic strategy for epilepsy and seizure-related neurological disorders. Full article

Background: The primary aim of this Phase 1 clinical trial was to study the safety and dose of a cholecystokinin receptor antagonist, proglumide, in combination with gemcitabine/nab-paclitaxel (GEM-NAB-P) in patients with metastatic pancreatic cancer. The secondary aim was to study the effects of proglumide with GEM-NAB-P on the tumor microenvironment (TME) with tumor biopsies and a blood biomarker assay. An exploratory aim studied the effects of proglumide treatment on cancer-related pain. Methods: Gemcitabine-naïve patients were treated with GEM-NAB-P plus proglumide 1200 mg/day. Tumor biopsies and a liquid biopsy serum sample for analysis of a microRNA biomarker panel were collected pre- and on-treatment to study the TME. McGill pain surveys were done at baseline, week 8 and at the end of treatment. The study was approved and registered (NCT05827055). Results: The mean age of the patients was 68.2 years (range 54–74 years). The starting dose was well-tolerated with no unexpected treatment-related adverse events observed. Multiplex immunohistochemical analysis of tumor biopsies at baseline and week 8 revealed a significant reduction in Ki67+ cells, collagen1α1, and M2-polarized tumor-associated macrophages (TAMs). Week 8 tumor biopsies demonstrated a significant increase in CD8+ T-cells and natural killer cells compared to baseline. The blood biomarker panel showed a significant inverse change in microRNAs associated with decreasing fibrosis and metastasis. The McGill pain scores showed less pain at week 24 or end-of-treatment compared to baseline. Conclusions: Proglumide demonstrates a favorable safety profile when combined with standard chemotherapy for metastatic pancreatic cancer. Its unique ability to remodel TME and alleviate cancer-related pain highlights its potential, warranting further research. Full article

The substitution of fish meal with soybean meal (SBM) in aquafeeds aligns with sustainable development but often leads to depressed feed intake and growth in fish. This study aimed to investigate the mitigating effect of earthworm powder (EP) on these negative impacts in rice field eels (Monopterus albus), focusing on appetite regulation, intestinal health, and gut microbiota. Three isonitrogenous (~41% crude protein) and isolipidic (~6.4% crude lipid) diets (control [CON], high-SBM [SBM], and SBM + 2.5% EP [EP]) were tested in a 56-day trial. Juveniles (initial weight 18.00 ± 0.01 g) were stocked at 40 fish per net (0.5 m × 0.5 m× 0.5 m) and fed to visual satiety once daily. The results indicated that EP improved growth performance through a dual mechanism. Firstly, it was associated with significantly increased feed intake, correlated with the upregulated expression of orexigenic genes (agrp, npy) in the brain, and associated with reduced levels of anorexigenic hormones (Cholecystokinin, Leptin). Secondly, it correlated with enhanced intestinal health, evidenced by improved morphology (villus height, goblet cells), improved digestive enzyme activity, enhanced antioxidant capacity (increased Catalase and Superoxide Dismutase activities), repaired intestinal barrier function (upregulated zo-1, cla-12), and alleviated intestinal inflammation (downregulated tnf-α, il-1β). Furthermore, EP supplementation was associated with a shift in gut microbiota, including the suppression of the potential pathogen g_Clostridium_T and promotion of the beneficial bacterium g_Lactococcus_A, alongside increased concentrations of major short-chain fatty acids (acetate, propionate, and butyrate). These correlative observations suggest that EP may help mitigate the growth-inhibiting effects of SBM in Monopterus albus, offering a potential functional strategy for high-SBM aquafeeds. Full article

G protein-coupled receptors (GPCR) are targeted by more than one third of the clinically available drugs as specific ligands. Important as GPCR ligands may be, cases of ligand-independent GPCR activation are also abundant. In a recent article published in the journal ACS Nano, a series of cyanine skeleton-based plasmonic molecules, or molecular jackhammer, as the authors christened them, after insertion into the plasma membrane, was found after excitation by far-red light (730 nm) to vibronically-driven activate Gq-mediated calcium signaling in four different cell lines of both epithelial and muscle cell origin, which is normally activated after agonist stimulation of Gq-coupled GPCR, but the possible involvement of GPCR remains to be examined. This novel mode of activation of calcium signaling, normally associated with agonist-stimulated GPCR activation, is compared to nanoclustering activation of the neuropeptide Y2 receptor and photodynamic activation of the cholecystokinin 1 and 2 receptors. Full article

Pancreatic exocrine secretion is regulated by the physicochemical properties and nutrient composition of gastric and intestinal chyme. The present study examined integrative feedback mechanisms involved in the physiological control of pancreatic secretion, with particular emphasis on interactions between pancreatic juice, bile, and gut-derived regulatory and metabolic signals. A chronic porcine model enabling selective withdrawal and controlled reintroduction of pancreatic juice and bile into defined intestinal segments was employed. Duodenal and ileal exposure to pancreatic juice suppressed pancreatic enzyme secretion, while intraduodenal administration of pancreatin elicited a biphasic inhibitory response. Interruption of bile flow to the duodenum resulted in increased pancreatic protein output and was associated with reduced circulating cholecystokinin concentrations. In contrast, intraduodenal infusion of bile acids attenuated pancreatic exocrine secretion. Prolonged bile deprivation led to sustained pancreatic hypersecretion accompanied by a marked reduction in biliary leptin output. Collectively, these findings indicate that pancreatic exocrine secretion in pigs is regulated by multiple interacting feedback pathways operating along the gastrointestinal tract. The observed responses support functional contributions of protease-dependent luminal feedback, distal intestinal sensing, hormone-dependent regulation, and bile-associated metabolic modulation. Full article

Background/Objectives: Peptide receptor radionuclide therapy (PRRT) is an established treatment for neuroendocrine tumors (NETs), enabling targeted radiation delivery via radiolabeled peptides. Small cell lung cancer (SCLC) remains a major therapeutic challenge due to its aggressive nature and poor prognosis. Despite advances, relapse rates are high and effective therapies are limited. We previously demonstrated the diagnostic potential of the cholecystokinin-2 receptor (CCK2R)-targeting minigastrin analog [⁶⁸Ga]Ga-DOTA-MGS5 in PET/CT imaging of different NETs. Building on this, we developed and evaluated [¹⁷⁷Lu]Lu-DOTA-MGS5 as a therapeutic PRRT agent. Methods: Preclinical studies investigating the receptor-mediated cellular internalization and intracellular distribution over time in A431 cells with and without CCK2R expression were performed using the fluorescent tracer ATTO-488-MGS5. Short- and long-term cytotoxic effects of [¹⁷⁷Lu]Lu-DOTA-MGS5 were evaluated on the same cell line using trypan blue exclusion and clonogenic survival assays. CCK2R expression was assessed by immunohistochemistry in 42 SCLC tissue specimens. In addition, the first PRRT with [¹⁷⁷Lu]Lu-DOTA-MGS5 was conducted in a patient with extensive disease SCLC (ED-SCLC) after confirming CCK2R-positive uptake in [⁶⁸Ga]Ga-DOTA-MGS5 PET/CT. Results: Rapid binding and internalization into A431-CCK2R cells, with progressive accumulation in intracellular compartments, was observed for ATTO-488-MGS5. Short-term irradiation effects of [¹⁷⁷Lu]Lu-DOTA-MGS5 were comparable for 4 h and 24 h incubation and were between the effects obtained with 2 and 4 Gy of external beam radiotherapy (EBRT). Clonogenic survival of A431-CCK2R cells incubated with increasing activity of [¹⁷⁷Lu]Lu-DOTA-MGS5 decreased in a dose-dependent manner. Immunohistochemistry on SCLC specimens confirmed moderate to high CCK2R expression in 16 out of 42 SCLC samples. In the first patient with SCLC treated with four cycles of [¹⁷⁷Lu]Lu-DOTA-MGS5 with a total activity of 17.2 GBq, an improvement in clinical symptoms was observed. Conclusions: The preclinical and clinical results confirm the feasibility of [¹⁷⁷Lu]Lu-DOTA-MGS5 PRRT in patients with SCLC and support further clinical studies investigating the therapeutic value and clinical applicability of this new CCK2R-targeted theranostic approach in larger patient cohorts. Full article

During gastrointestinal digestion, dietary proteins are hydrolyzed into peptides and free amino acids that modulate enteroendocrine function and satiety-related hormone secretion along the gut–brain axis, thereby contributing to obesity prevention. We investigated whey protein concentrate (WPC) as a source of bioactive peptides and evaluated the effects of its digests on cholecystokinin (CCK) secretion in STC-1 enteroendocrine cells by integrating the standardized INFOGEST in vitro digestion protocol, peptidomics (LC–MS/MS), and in silico bioactivity prediction. In STC-1 cells, the <3 kDa intestinal peptide fraction exhibited the strongest CCK stimulation, positioning these low-molecular-weight peptides as promising bioactive components for satiety modulation and metabolic health applications. Peptidomic analysis of this fraction identified short sequences derived primarily from β-lactoglobulin (β-La) and α-lactalbumin (α-La), enriched in hydrophobic and aromatic residues, including neuropeptide-like sequences containing the Glu–Asn–Ser–Ala–Glu–Pro–Glu (ENSAEPE) motif of β-La f(108–114). In silico bioactivity profiling with MultiPep predicted antihypertensive, angiotensin-converting enzyme (ACE)–inhibitory, antidiabetic, dipeptidyl peptidase-IV (DPP-IV)–inhibitory, antioxidant, antibacterial, and neuropeptide-like activities. Overall, digestion of WPC released low-molecular-weight peptides and amino acids that enhanced CCK secretion in vitro; these findings support their potential use in nutritional strategies to enhance satiety, modulate appetite and energy intake, and improving cardiometabolic health. Full article

Cholecystokinin 1 receptor (CCK1R) is activated by singlet oxygen (¹O₂) in type II photodynamic action in isolated rat, mouse, and Peking duck pancreatic acini. To examine whether this is maintained outside the microenvironment of pancreatic acinar cell, photodynamic activation of CCK1R from human, rat, mouse, and Peking duck expressed in CHO-K1 cells was examined, as monitored with Fura-2 fluorescence calcium imaging. Photodynamic action with sulphonated aluminum phthalocyanine was found to trigger persistent calcium oscillations in CCK1R-CHO-K1 cells transfected with human, rat, mouse or Peking duck CCK1R gene, which were blocked by ¹O₂ quencher Trolox C. After tagging protein photosensitizer miniSOG to C-terminus of these CCK1R, photodynamic action was found to similarly trigger persistent calcium oscillations in CCK1R-miniSOG-CHO-K1 cells expressing human, rat, mouse, and Peking duck receptor constructs. Incubation with Trolox C 300 μM during LED light irradiation also prevented photodynamic CCK1R activation in CCK1R-miniSOG-CHO-K1 cells. In contrast, human M3R was not photodynamically activated with SALPC or tagged miniSOG as the photosensitizer. These data, together, suggest that photodynamic CCK1R activation is maintained outside of the pancreatic acinar cell, making possible photodynamic CCK1R activation in CCK1R-expressing organs and tissues other than the pancreas, with high spatiotemporal precision. Full article

Pancreatic cancer is characterized by an extensive fibrotic stroma largely driven by activated pancreatic stellate cells (PSCs)/fibroblasts, which also function to support tumor growth and metastasis. Cholecystokinin-B receptors (CCK-BRs) are expressed on pancreatic stellate cells (PSCs) and have emerged as a key regulator of PSC activation and tumor-stromal interactions. We hypothesized that disrupting CCK-BR function shifts PSCs to a more quiescent phenotype and reduces their pro-fibrotic and tumor-supportive activity to decrease growth of pancreatic cancer. Murine PSCs were genetically engineered with CRISPR-Cas9 to knockout the CCK-BR. In a series of experiments, the role of the CCK-BR expression was evaluated on cell migration, proliferation, differentially expressed genes, molecular signaling pathways, and in co-culture with murine pancreatic cancer epithelial cells. Next, primary human pancreatic stellate cells were treated with proglumide, a CCK-BR antagonist, to study the effects of pharmacologic blockade of the CCK-BR on cellular signaling and proliferative pathways by RNA sequencing. Knockout of the CCK-BR led to significant decreases in PSC activation and the ability to stimulate growth of pancreatic cancer cells in co-culture. Both genetic knockdown and pharmacologic blockade of the CCK-BR downregulated genes implicated in fibrosis, proliferation, fibroblast activation, and tumorigenesis, while genes implicated in apoptosis and tumor suppression were upregulated. Flow cytometry showed increased apoptosis markers in CCK-BR-knockout cells compared to controls. These experiments combine transcriptomic profiling with functional validation to provide a comprehensive analysis of how targeting CCK-BR interrupts the cross-communication between cancer cells and fibroblasts. Blockade or downregulation of the CCK-BR on pancreatic fibroblasts may provide a strategy to disrupt oncogenic signaling pathways and reprogram the tumor microenvironment. Full article

The mouse enteroendocrine cell line STC-1 has been widely used to investigate the effects of dietary protein-derived peptides on cholecystokinin (CCK) secretion. The studies have also addressed the question of whether specific structural features of a given peptide chain may be related to higher secretagogue activity with respect to others, but a detailed structure–activity relationship in CCK-releasing peptides has not yet been reported. The aim of this study was to list the currently available CCK-releasing peptide sequences; to draw conclusions about the role played by peptide length, peptide amino acid composition and peptide amino acid sequence in differentiating their secretagogue activity; and to highlight the physicochemical properties and sequence motifs shared by the active peptides, and any possible differential feature between CCK-releasing peptides and ineffective peptides. To this end, a method was applied consisting of the fractionation of peptide sets into subsets and the comparison between paired subsets of active and inactive peptides. A few distinctive structural features related to CCK-releasing activity were highlighted for each subset. Actually, minor changes in the primary structure can make the difference between active and inactive peptides, as suggested by previous studies. Hence, the chance of predicting the activity of a peptide that has never been tested in vitro using reference structures must still be considered to be low. Full article

Diabetes remains a global health challenge, characterized by persistent hyperglycemia and gradual depletion or impairment of pancreatic β-cells. Current treatments focus on managing glycemic control, but do not mitigate β-cell mass. Verapamil, an FDA-approved calcium channel blocker for hypertension, has shown potential therapeutic action towards β-cells in the context of diabetes. In this study, we investigated the cytoprotective and metabolic efficacy of verapamil on mouse-derived MIN6 β-cells under metabolic and diabetogenic stressors like high glucose, toxins, and an inflammatory cytokine cocktail, as well as investigated a zebrafish model. At safe, non-toxic doses, verapamil elevated the levels of cholecystokinin (CCK), an incretin associated with β-cell preservation and enhanced mitochondrial respiration. Notably, pretreatment and co-treatment of verapamil in the presence of stressors offered substantial protection and preserved mitochondrial function, whereas post-treatment effects were moderate and model dependent. In the zebrafish model, verapamil promoted β-cell recovery and regeneration before, during, and after targeted ablation. The drug seemed to work in several ways: inducing proliferation, reducing stress on β cells, boosting their energy production, and activating survival signals. Together, our data aligned with earlier human clinical trials showing that verapamil administration preserved β-cell mass and function in patients with recent-onset type 1 diabetes. The high efficacy, affordability, and broad mechanisms of action make verapamil a desirable therapeutic candidate for diabetes. Nevertheless, further mechanistic studies and long-term clinical trials are warranted to establish its utility in diabetes management. Full article

The early developmental transition from endogenous to exogenous feeding is a critical period in carnivorous fish larvae, often associated with high mortality rates in aquaculture. Although trypsin, a key protease in protein digestion, is hypothesized to play a pivotal role in initiating exogenous feeding, the expression dynamics and functional contributions of trypsin and isoforms during early development remain poorly characterized in carnivorous species. This study explores the critical role of trypsin in the early feeding process of carnivorous fish, using mandarin fish (Siniperca chuatsi) as a model, which is a commercially valuable species that faces significant challenges during this phase due to its strict dependence on live prey and underdeveloped digestive system. Phylogenetic analysis indicates that, compared to herbivorous and omnivorous fish, carnivorous fish have evolved a greater number of trypsins, with a distinct branch specifically dedicated to try. RNA-seq data revealed the expression profiles of 13 trypsins during the early developmental stages of the mandarin fish. Most trypsins began to be expressed in large quantities with the appearance of the pancreas, reaching a peak prior to feeding. In situ hybridization revealed the spatiotemporal expression pattern of trypsins, starting from the pancreas in early development and later extending to the intestines. Furthermore, inhibition of trypsins activity successfully suppressed early oral feeding in mandarin fish, which was achieved by increasing the expression of cholecystokinin 2 (CCK2) and proopiomelanocortin (POMC) to suppress appetite. These findings enhance our understanding of the adaptive relationship between the ontogeny of the digestive enzyme system and feeding behavior in carnivorous fish. This research may help alleviate bottleneck issues in aquaculture production by improving the survival rate and growth performance of carnivorous fish during critical early life stages. Full article

Leptin, an adipocyte-derived hormone, plays a central role in the regulation of energy homeostasis by acting on distinct hypothalamic nuclei. This review explores recent advances in our understanding of leptin’s region-specific actions within the arcuate nucleus, ventromedial hypothalamus, dorsomedial hypothalamus, and lateral hypothalamus, highlighting their contributions to appetite regulation, energy expenditure, and neuroendocrine function. In the hypothalamic arcuate nucleus, leptin’s differential regulation of pro-opiomelanocortin and agouti-related peptide/neuropeptide Y neurons is now complemented by the identification of novel leptin-responsive neuronal populations—such as those expressing prepronociceptin, basonuclin 2, and Pirt—as well as a growing array of cellular and molecular modulators, including secreted factors like angiopoietin-like growth factor, zinc-α2-glycoprotein, and spexin, intracellular regulators such as Rap1, growth factor receptor-bound protein 10, and spliced X-box binding protein 1. In the ventromedial hypothalamus, leptin integrates with both peripheral (e.g., cholecystokinin) and central (e.g., pituitary adenylate cyclase-activating polypeptide) signals, while epigenetic mechanisms, such as those mediated by Jumonji domain-containing protein D3, regulate leptin receptor expression and sensitivity. The dorsomedial hypothalamus is increasingly recognized for coordinating leptin’s effects on metabolism, circadian rhythms, and respiration through distinct neuronal populations, including a subset of neurons co-expressing GLP-1 receptors that mediate leptin’s metabolic effects. In the lateral hypothalamus, leptin modulates reward-driven feeding via GABAergic neuronal populations—circuits that are particularly susceptible to disruption following early life trauma. Together, these insights reveal a sophisticated neurobiological framework through which leptin orchestrates systemic physiology. Understanding the heterogeneity of leptin signaling opens new avenues for restoring leptin sensitivity and developing personalized therapeutic strategies to combat obesity and related metabolic disorders. Full article