Search Results (39)

Colon cancer is one of the leading malignant tumors worldwide, and the membrane protein PAQR3 has been identified as a tumor suppressor in multiple cancers. Notably, the peptide synthesized from 6 to 55 amino acids at the N-terminal of PAQR3 (P6-55) has been shown to effectively inhibit the growth of gastric cancer cells. This study aims to elucidate the mechanism of PAQR3 and explore its therapeutic potential in colon cancer. CCK8 cell viability assays, colony formation assays, and transwell migration assays were employed to systematically assess the inhibitory effects of PAQR3 on the proliferation and migration of colon cancer cells. Furthermore, we confirmed that P6-55 exhibits functional similarities to PAQR3, effectively inhibiting the growth of colon cancer in vitro and in vivo. RNA sequencing revealed that PAQR3 suppresses tumor growth via the PI3K-AKT signaling pathway, providing a strong theoretical foundation for therapeutic strategies targeting PAQR3/P6-55. In conclusion, our findings highlight the therapeutic potential of PAQR3/P6-55 as novel colon cancer inhibitors. Full article

Obesity, insulin resistance, type 2 diabetes mellitus (T2DM) and metabolic syndrome have been largely correlated to a reduction in bacterial load and diversity, resulting in a condition known as intestinal dysbiosis. The recent emergence of novel antidiabetic medications has been demonstrated to exert a favourable influence on the composition of the intestinal microbiota. Incretin-based therapy exerts a multifaceted influence on the composition of the gut microbiota, leading to alterations in bacterial flora. Of particular significance is the capacity of numerous metabolites produced by the gut microbiota to modulate the activity and hormonal secretion of enteroendocrine cells. This review examines the effects of dipeptidyl peptidase 4 (DPP-4) inhibitors, glucagon-like peptide 1 (GLP-1) receptor agonists and GLP-1/gastric inhibitory polypeptide (GIP) receptor dual agonists on the composition of the gut microbiota in both mice and human subjects. The nature of this interaction is complex and bidirectional. The present study demonstrates the involvement of the incretinic axis in modulating the microbial composition, with the objective of providing novel preventative strategies and potential personalised therapeutic targets for obesity and T2DM. Full article

Type 2 Diabetes (T2D) is a complex metabolic disorder that affects multiple organs, leading to severe complications in the pancreas, kidneys, liver, and heart. Prolonged hyperglycemia, along with oxidative stress and chronic inflammation, plays a crucial role in accelerating tissue damage, significantly increasing the risk of diabetic complications such as nephropathy, hepatopathy, and cardiovascular disease. This review evaluates the protective effects of various antidiabetic treatments on organ tissues affected by T2D, based on findings from experimental animal models. Metformin, a first-line antidiabetic agent, has been widely recognized for its ability to reduce inflammation and oxidative stress, thereby mitigating diabetes-induced organ damage. Its protective role extends beyond glucose regulation, offering benefits such as improved mitochondrial function and reduced fibrosis in affected tissues. In addition to traditional therapies, new classes of antidiabetic drugs, including sodium-glucose co-transporter-2 inhibitors and glucagon-like peptide-1 (GLP-1) receptor agonists not only improve glycemic control but also exhibit nephroprotective and cardioprotective properties by reducing glomerular hyperfiltration, oxidative stress, and inflammation. Similarly, GLP-1 receptor agonists have been associated with reduced hepatic steatosis and enhanced cardiovascular function. Preclinical studies suggest that tirzepatide, a dual GLP-1/gastric inhibitory polypeptide receptor agonist may offer superior metabolic benefits compared to conventional GLP-1 agonists by improving β-cell function, enhancing insulin sensitivity, and reducing fatty liver progression. Despite promising preclinical results, differences between animal models and human physiology pose a challenge. Further clinical research is needed to confirm these effects and refine treatment strategies. Future T2D management aims to go beyond glycemic control, emphasizing organ protection and long-term disease prevention. Full article

Background/Objectives: Yerba maté (YM), a traditional herbal beverage made from Ilex paraguariensis, contains bioactive compounds like polyphenols and alkaloids known for their metabolic benefits. This study investigates YM’s incretin effects, focusing on glucagon-like peptide-1 (GLP-1) and gastric inhibitory polypeptide (GIP). Methods: Male and female C57BL/6 mice were supplemented with YM for four weeks. Post-supplementation, GLP-1 and GIP gene expression levels were analyzed in jejunal mucosa, and plasma hormone concentrations were measured. Additionally, in vitro experiments were conducted using GLUTag L-cells to evaluate the direct effects of YM and its metabolites, including ferulic acid and dihydroferulic acid, on GLP-1 secretion. Gene expression analysis involved quantitative real-time PCR, while hormone levels were assessed via ELISA. Results: YM supplementation significantly increased GLP-1 gene expression and plasma GLP-1 levels compared to controls, with no changes observed in GIP expression or plasma levels. Direct treatment of GLUTag L-cells with YM did not enhance GLP-1 secretion. However, dihydroferulic acid, a microbial metabolite of ferulic acid, markedly stimulated GLP-1 production in L-cells, highlighting a role of gut-mediated metabolism in YM’s incretin effects. Conclusions: YM selectively upregulates GLP-1 pathways without affecting GIP, likely through gut-mediated mechanisms. These findings suggest YM as a promising nutraceutical for incretin modulation and metabolic disorder management. Further studies should explore the interplay between YM, the gut microbiota, and incretin pathways to fully realize its therapeutic potential. Full article

Rotenone, a naturally occurring compound derived from the roots of tropical plants, is used as a broad-spectrum insecticide, piscicide, and pesticide. It is a classical, high-affinity mitochondrial complex I inhibitor that causes not only oxidative stress, α-synuclein phosphorylation, DJ-1 (Parkinson’s disease protein 7) modifications, and inhibition of the ubiquitin-proteasome system but it is also widely considered an environmental contributor to Parkinson’s disease (PD). While prodromal symptoms, such as loss of smell, constipation, sleep disorder, anxiety/depression, and the loss of dopaminergic neurons in the substantia nigra of rotenone-treated animals, have been reported, alterations of metabolic hormones and hyperinsulinemia remain largely unknown and need to be investigated. Whether rotenone and its effect on metabolic peptides could be utilized as a biomarker for its toxic metabolic effects, which can cause long-term detrimental effects and ultimately lead to obesity, hyperinsulinemia, inflammation, and possibly gut–brain axis dysfunction, remains unclear. Here, we show that rotenone disrupts metabolic homeostasis, altering hormonal peptides and promoting infiltration of inflammatory T cells. Specifically, our results indicate a significant decrease in glucagon-like peptide-1 (GLP-1), C-peptide, and amylin. Interestingly, levels of several hormonal peptides related to hyperinsulinemia, such as insulin, leptin, pancreatic peptide (PP), peptide YY (PYY), and gastric inhibitory polypeptide (GIP), were significantly upregulated. Administration of rotenone to rats also increased body weight and activated macrophages and inflammatory T cells. These data strongly suggest that rotenone disrupts metabolic homeostasis, leading to obesity and hyperinsulinemia. The potential implications of these findings are vast, given that monitoring these markers in the blood could not only provide a crucial tool for assessing the extent of exposure and its relevance to obesity and inflammation but could also open new avenues for future research and potential therapeutic strategies. Full article

Cardiovascular–Kidney–Metabolic syndrome, introduced by the American Heart Association in 2023, represents a complex and interconnected spectrum of diseases driven by shared pathophysiological mechanisms. However, this framework notably excludes the liver—an organ fundamental to metabolic regulation. Building on this concept, Cardiovascular–Renal–Hepatic–Metabolic (CRHM) syndrome incorporates the liver’s pivotal role in this interconnected disease spectrum, particularly through its involvement via metabolic dysfunction-associated steatotic liver disease (MASLD). Despite the increasing prevalence of CRHM syndrome, unified management strategies remain insufficiently explored. This review addresses the following critical question: How can novel anti-diabetic agents, including sodium–glucose cotransporter-2 inhibitors (SGLT2is), glucagon-like peptide-1 receptor agonists (GLP-1RAs), and dual gastric inhibitory polypeptide (GIP)/GLP-1RA, offer an integrated approach to managing CRHM syndrome beyond the boundaries of traditional specialties? By synthesizing evidence from landmark clinical trials, we highlight the paradigm-shifting potential of these therapies. SGLT2is, such as dapagliflozin and empagliflozin, have emerged as cornerstone guideline-directed treatments for heart failure (HF) and chronic kidney disease (CKD), providing benefits that extend beyond glycemic control and are independent of diabetes status. GLP-1RAs, e.g., semaglutide, have transformed obesity management by enabling weight reductions exceeding 15% and improving outcomes in atherosclerotic cardiovascular disease (ASCVD), diabetic CKD, HF, and MASLD. Additionally, tirzepatide, a dual GIP/GLP-1RA, enables unprecedented weight loss (>20%), reduces diabetes risk by over 90%, and improves outcomes in HF with preserved ejection fraction (HFpEF), MASLD, and obstructive sleep apnea. By moving beyond the traditional organ-specific approach, we propose a unified framework that integrates these agents into holistic management strategies for CRHM syndrome. This paradigm shift moves away from fragmented, organ-centric management toward a more unified approach, fostering collaboration across specialties and marking progress in precision cardiometabolic medicine. Full article

Metabolic peptides can influence metabolic processes and contribute to both inflammatory and/or anti-inflammatory responses. Studies have shown that there are thousands of metabolic peptides, made up of short chains of amino acids, that the human body produces. These peptides are crucial for regulating many different processes like metabolism and cell signaling, as they bind to receptors on various cells. This review will cover the role of three specific metabolic peptides and their roles in hyperinsulinemia, diabetes, inflammation, and neurodegeneration, as well as their roles in type 3 diabetes and dementia. The metabolic peptides glucagon-like peptide 1 (GLP-1), gastric inhibitor polypeptide (GIP), and pancreatic peptide (PP) will be discussed, as dysregulation within their processes can lead to the development of various inflammatory and neurodegenerative diseases. Research has been able to closely investigate the connections between these metabolic peptides and their links to the gut–brain axis, highlighting changes made in the gut that can lead to dysfunction in processes in the brain, as well as changes made in the brain that can lead to dysregulation in the gut. The role of metabolic peptides in the development and potentially reversal of diseases such as obesity, hyperinsulinemia, and type 2 diabetes will also be discussed. Furthermore, we review the potential links between these conditions and neuroinflammation and the development of neurodegenerative diseases like dementia, specifically Parkinson’s disease and Alzheimer’s disease. Full article

The last two decades have provided far more options f both patients and their physicians in the treatment of diabetes mellitus. While dipeptidyl peptidase-4 inhibitors (DPP-4is) and glucagon-like peptide 1 receptor agonists (GLP-1RAs) have been approved for nearly two decades, sodium–glucose cotransporter 2 inhibitors (SGLT-2is) are relatively new. Of interest to perioperative physicians, these drugs present specific perioperative concerns, prompting many societies to issue guidelines. Retained gastric contents due to slow gastric emptying is a significant drawback of GLP-1RAs, increasing the risk of aspiration. Recommendations include withholding GLP-1RAs for a predefined period of time, performing gastric ultrasound to evaluate gastric contents, modifying anesthesia management, particularly with regard to the airway, or canceling the scheduled (elective) surgery or procedure. SGLT-2is are known to increase the risk of euglycemic ketoacidosis. The benefits of both GLP-1RAs and SGLT-2is extend beyond the treatment of diabetes. As a result, perioperative physicians may encounter their use outside of their traditional indications. SGLT-2is are being used extensively to treat heart failure and obesity, for example. There have been other developments as well. For instance, Imeglimin, a variant of metformin available in Japan and India, Icodec, a once-weekly basal insulin formulation, and IcoSema, a once-weekly combination of Icodec plus semaglutide, are all being explored, although in their early stages or facing approval challenges. Full article

Background/Objectives: Human epidermal growth factor receptor 2 (HER2) is overexpressed in several malignancies, such as breast, gastric, ovarian, and lung cancers, where it promotes aggressive tumor proliferation and unfavorable prognosis. Targeting HER2 has thus emerged as a crucial therapeutic strategy, particularly for HER2-positive malignancies. The present study focusses on the design and optimization of peptide inhibitors targeting HER2, utilizing machine learning to identify and enhance peptide candidates with elevated binding affinities. The aim is to provide novel therapeutic options for malignancies linked to HER2 overexpression. Methods: This study started with the extraction and structural examination of the HER2 protein, succeeded by designing the peptide sequences derived from essential interaction residues. A machine learning technique (XGBRegressor model) was employed to predict binding affinities, identifying the top 20 peptide possibilities. The candidates underwent further screening via the FreeSASA methodology and binding free energy calculations, resulting in the selection of four primary candidates (pep-17, pep-7, pep-2, and pep-15). Density functional theory (DFT) calculations were utilized to evaluate molecular and reactivity characteristics, while molecular dynamics simulations were performed to investigate inhibitory mechanisms and selectivity effects. Advanced computational methods, such as QM/MM simulations, offered more understanding of peptide–protein interactions. Results: Among the four principal peptides, pep-7 exhibited the most elevated DFT values (−3386.93 kcal/mol) and the maximum dipole moment (10,761.58 Debye), whereas pep-17 had the lowest DFT value (−5788.49 kcal/mol) and the minimal dipole moment (2654.25 Debye). Molecular dynamics simulations indicated that pep-7 had a steady binding free energy of −12.88 kcal/mol and consistently bound inside the HER2 pocket during a 300 ns simulation. The QM/MM simulations showed that the overall total energy of the system, which combines both QM and MM contributions, remained around −79,000 ± 400 kcal/mol, suggesting that the entire protein–peptide complex was in a stable state, with pep-7 maintaining a strong, well-integrated binding. Conclusions: Pep-7 emerged as the most promising therapeutic peptide, displaying strong binding stability, favorable binding free energy, and molecular stability in HER2-overexpressing cancer models. These findings suggest pep-7 as a viable therapeutic candidate for HER2-positive cancers, offering a potential novel treatment strategy against HER2-driven malignancies. Full article

Background: The increased popularity and ubiquitous use of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) for the treatment of diabetes, heart failure, and obesity has led to significant concern for increased risk for perioperative aspiration, given their effects on delayed gastric emptying. This concern is highlighted by many major societies that have published varying guidance on the perioperative management of these medications, given limited data. We conducted a scoping review of the available literature regarding the aspiration risk and aspiration/regurgitant events related to GLP-1 RAs. Methods: A librarian-assisted search was performed using five electronic medical databases (PubMed, Embase, and Web of Science Platform Databases, including Web of Science Core Collection, KCI Korean Journal Database, MEDLINE, and Preprint Citation Index) from inception through March 2024 for articles that reported endoscopic, ultrasound, and nasogastric evaluation for increased residual gastric volume retained food contents, as well as incidences of regurgitation and aspiration events. Two reviewers independently screened titles, abstracts, and full text of articles to determine eligibility. Data extraction was performed using customized fields established a priori within a systematic review software system. Results: Of the 3712 citations identified, 24 studies met eligibility criteria. Studies included four prospective, six retrospective, five case series, and nine case reports. The GLP-1 RAs reported in the studies included semaglutide, liraglutide, lixisenatide, dulaglutide, tirzepatide, and exenatide. All studies, except one case report, reported patients with confounding factors for retained gastric contents and aspiration, such as a history of diabetes, cirrhosis, hypothyroidism, psychiatric disorders, gastric reflux, Barrett’s esophagus, Parkinson’s disease, dysphagia, obstructive sleep apnea, gastric polyps, prior abdominal surgeries, autoimmune diseases, pain, ASA physical status classification, procedural factors (i.e., thyroid surgery associated with risk for nausea, ketamine associated with nausea and secretions), and/or medications associated with delayed gastric emptying (opioids, anticholinergics, antidepressants, beta-blockers, calcium channel blockers, DPP-IV inhibitors, and antacids). Of the eight studies (three prospective and five retrospective) that evaluated residual contents in both GLP-1 users and non-users, seven studies (n = 7/8) reported a significant increase in residual gastric contents in GLP-1 users compared to non-users (19–56% vs. 5–20%). In the three retrospective studies that evaluated for aspiration events, there was no significant difference in aspiration events, with one study reporting aspiration rates of 4.8 cases per 10,000 in GLP-1 RA users compared to 4.6 cases per 10,000 in nonusers and the remaining two studies reporting one aspiration event in the GLP-1 RA user group and none in the non-user group. In one study that evaluated for regurgitation or reflux by esophageal manometry and pH, there was no significant difference in reflux episodes but a reduction in gastric acidity in the GLP-1 RA user group compared to the non-user group. Conclusions: There is significant variability in the findings reported in the studies, and most of these studies include confounding factors that may influence the association between GLP-1 RAs and an increased risk of aspiration and related events. While GLP-1 RAs do increase residual gastric contents in line with their mechanism of action, the currently available data do not suggest a significant increase in aspiration and regurgitation events associated with their use and the withholding of GLP-1 RAs to reduce aspiration and regurgitation events, as is currently recommended by many major societal guidelines. Large randomized controlled trials (RCTs) may be helpful in further elucidating the impact of GLP-1 RAs on perioperative aspiration risk. Full article

Objectives: We characterized blood glucose fluctuations in patients with myotonic dystrophy type 1 (DM1). After confirming the incretin secretion capacity of patients with DM1, we intended to clarify whether dipeptidyl peptidase 4 (DPP-4) inhibitor administration was appropriate in cases of DM1 with diabetes mellitus. Methods: A 48 h continuous glucose monitoring (CGM) was performed in 29 Japanese patients with DM1. An oral glucose tolerance test (OGTT) was performed in patients with DM1 and five disease controls, and levels of blood glucose, insulin, and incretin (glucagon-like peptide-1 and gastric inhibitory polypeptide) were measured. DPP-4 inhibitors were administered to patients with diabetes mellitus complicated by DM1, and the CGM results were compared. Results: The CGM showed distinct patterns of blood glucose variability among patients classified by an OGTT pattern with significant differences in glucose parameters such as time above 140 mg/dL and mean amplitude of glycemic excursions between the groups. High sensor glucose values were observed in a certain number of patients who were classified as having normal or impaired glucose tolerance by the OGTT. The CGM confirmed the presence of low glucose levels in several patients. Incretin secretion, the target of DPP-4 inhibitors, was preserved in patients with DM1. DPP-4 inhibitor treatment resulted in lower glucose levels and improved insulin secretion in some patients. Conclusions: This is the first CGM study for DM1 patients. The CGM identified potential early abnormalities in glucose metabolism in DM1. In the future, it will be crucial to explore effective methods for harnessing CGM and assessing it quantitatively in DM1. Full article

Background: Impaired gastric motility in the form of constipation may often occur in elderly patients with chronic heart failure. Candidates for trans-catheter aortic replacement (TAVR) are of old age and have multiple comorbidities, probably including constipation. However, the clinical implication of a history of constipation in patients receiving TAVR remains unknown. Methods: Patients who underwent TAVR at our large academic center between 2015 and 2022 were eligible. The prognostic impact of the prescribed laxative type and number, which was assumed as the severity of constipation, on the incidence of death or heart failure readmission two years after index discharge was investigated. Results: A total of 344 patients were included. Median age was 85 years, and 99 patients were men. Patients with any laxatives (N = 166) had higher systolic blood pressure, higher plasma B-type natriuretic peptide levels, and a lower prescription rate of renin–angiotensin system inhibitors at the time of index discharge after TAVR (p < 0.05 for all). The number of laxative types was independently associated with the composite primary outcome with an adjusted hazard ratio of 1.83 (95% confidence interval 1.27–2.63, p = 0.001) with a cutoff of one type of laxative used, which significantly stratified the 2-year cumulative incidence of the primary outcome (18% versus 7%, p = 0.001). Conclusions: The presence of constipation was associated with worse clinical outcomes following TAVR. The prognostic impact of an aggressive intervention for constipation remains a future concern in this cohort. Full article

Retinoblastoma (RB) is the most common malignant intraocular tumor in early childhood. Gene expression profiling revealed that the gastric inhibitory polypeptide receptor (GIPR) is upregulated following trefoil factor family peptide 1 (TFF1) overexpression in RB cells. In the study presented, we found this G protein-coupled transmembrane receptor to be co-expressed with TFF1, a new diagnostic and prognostic RB biomarker for advanced subtype 2 RBs. Functional analyses in two RB cell lines revealed a significant reduction in cell viability and growth and a concomitant increase in apoptosis following stable, lentiviral GIPR overexpression, matching the effects seen after TFF1 overexpression. In chicken chorioallantoic membrane (CAM) assays, GIPR-overexpressing RB cells developed significantly smaller CAM tumors. The effect of GIPR overexpression in RB cells was reversed by the GIPR inhibitor MK0893. The administration of recombinant TFF1 did not augment GIPR overexpression effects, suggesting that GIPR does not serve as a TFF1 receptor. Investigations of potential GIPR up- and downstream mediators suggest the involvement of miR-542-5p and p53 in GIPR signaling. Our results indicate a tumor suppressor role of GIPR in RB, suggesting its pathway as a new potential target for future retinoblastoma therapy. Full article

The present study was conducted to evaluate the protective effect of milk kefir against NSAID-induced gastric ulcers. Male Swiss mice were divided into three groups: control (Vehicle; UHT milk at a dose of 0.3 mL/100 g), proton pump inhibitor (PPI; lansoprazole 30 mg/kg), and 4% milk kefir (Kefir; 0.3 mL/100 g). After 14 days of treatment, gastric ulcer was induced by oral administration of indomethacin (40 mg/kg). Reactive oxygen species (ROS), nitric oxide (NO), DNA content, cellular apoptosis, IL-10 and TNF-α levels, and myeloperoxidase (MPO) enzyme activity were determined. The interaction networks between NADPH oxidase 2 and kefir peptides 1–35 were determined using the Residue Interaction Network Generator (RING) webserver. Pretreatment with kefir for 14 days prevented gastric lesions. In addition, kefir administration reduced ROS production, DNA fragmentation, apoptosis, and TNF-α systemic levels. Simultaneously, kefir increased NO bioavailability in gastric cells and IL-10 systemic levels. A total of 35 kefir peptides showed affinity with NADPH oxidase 2. These findings suggest that the gastroprotective effect of kefir is due to its antioxidant and anti-inflammatory properties. Kefir could be a promising natural therapy for gastric ulcers, opening new perspectives for future research. Full article

Adipokines are peptide hormones produced by the adipose tissue involved in several biological functions. Among adipokines, adiponectin (ADPN) has antidiabetic and anti-inflammatory properties. It can also modulate food intake at central and peripheral levels, acting on hypothalamus and facilitating gastric relaxation. ADPN exerts its action interacting with two distinct membrane receptors and triggering some well-defined signaling cascades. The ceramidase activity of ADPN receptor has been reported in many tissues: it converts ceramide into sphingosine. In turn, sphingosine kinase (SK) phosphorylates it into sphingosine-1 phosphate (S1P), a crucial mediator of many cellular processes including contractility. Using a multidisciplinary approach that combined biochemical, electrophysiological and morphological investigations, we explored for the first time the possible role of S1P metabolism in mediating ADPN effects on the murine gastric fundus muscle layer. By using a specific pharmacological inhibitor of SK2, we showed that ADPN affects smooth muscle cell membrane properties and contractile machinery via SK2 activation in gastric fundus, adding a piece of knowledge to the action mechanisms of this hormone. These findings help to identify ADPN and its receptors as new therapeutic targets or as possible prognostic markers for diseases with altered energy balance and for pathologies with fat mass content alterations. Full article