BMC Gastroenterol
March 2023
Background: Glucagon-like peptide-2 (GLP-2) enhances intestinal repair and attenuates inflammation in preclinical inflammatory bowel disease (IBD) models, making GLP-2 analogues attractive candidates for IBD therapy. Glepaglutide is a long-acting GLP-2 receptor agonist in clinical development for treatment of short bowel syndrome. Here, we investigated if glepaglutide is therapeutically beneficial in rats with small intestinal inflammation.
View Article and Find Full Text PDFThe aim of this study was to investigate whether inhibition of connexin 43 gap junction-uncoupling is sufficient to prevent retinal vascular cell loss under high glucose condition and reduce cell monolayer permeability. Rat retinal endothelial cells were grown for 3, 5, and 7 days in normal (5 mM) or high glucose (30 mM) medium; in parallel, cells grown in high glucose medium were exposed for 3, 5, and 7 days to 100 nM danegaptide, which stabilizes connexin 43-mediated cell coupling. Additionally, cells grown in normal medium were treated with a connexin 43 blocker as a negative control.
View Article and Find Full Text PDFBackground: Therapeutic hypothermia (TH) may increase the susceptibility to ventricular arrhythmias by decreasing ventricular conduction velocity (CV) and facilitating arrhythmogenic spatially discordant alternans (SDA).
Objective: The purpose of this study was to test the hypothesis that rotigaptide, a gap junction enhancer, can increase ventricular CV, delay the onset of SDA, and decrease the susceptibility to pacing-induced ventricular fibrillation (PIVF) during TH.
Methods: Langendorff-perfused isolated rabbit hearts were subjected to 30-minute moderate hypothermia (33°C) followed by 20-minute treatment with rotigaptide (300 nM, n = 8) or vehicle (n = 5).
Expert Opin Drug Discov
October 2014
Introduction: Lixisenatide is a once-daily short-acting glucagon-like peptide-1 (GLP-1) receptor agonist (GLP-1RA) used in the treatment of type 2 diabetes mellitus (T2DM). It is used in combination with oral antidiabetics and/or basal insulin in patients inadequately controlled on these medications and who are undergoing diet and lifestyle modification. GLP-1RAs glucose-dependently increase insulin secretion, decrease glucagon secretion, and slow gastric emptying, thereby improving glycemic control.
View Article and Find Full Text PDFOsteoclasts are formed by the fusion of mononuclear precursor cells of the monocyte-macrophage lineage. Among several putative mechanisms, gap-junctional intercellular communication (GJC) has been proposed to have a role in osteoclast fusion and bone resorption. We examined the role of GJC in osteoclastogenesis and in vitro bone resorption with mouse bone marrow hematopoietic stem cells and RAW 264.
View Article and Find Full Text PDFThe peptides encoded by the VGF gene are gaining biomedical interest and are increasingly being scrutinized as biomarkers for human disease. An endocrine/neuromodulatory role for VGF peptides has been suggested but never demonstrated. Furthermore, no study has demonstrated so far the existence of a receptor-mediated mechanism for any VGF peptide.
View Article and Find Full Text PDFBackground: Gap junctions are potential targets for pharmacologic intervention. We previously developed a series of peptide sequences that prevent closure of connexin43 (Cx43) channels, bind to cardiac Cx43, and prevent acidification-induced uncoupling of cardiac gap junctions.
Objective: The purpose of this study was to identify and validate the minimum core active structure in peptides containing an RR-N/Q-Y motif.
In an effort to discover potent, orally bioavailable compounds for the treatment of atrial fibrillation (AF) and ventricular tachycardia (VT), we developed a class of gap-junction modifiers typified by GAP-134 (1, R(1)=OH, R(2)=NH(2)), a compound currently under clinical evaluation. Selected compounds with the desired in-vitro profile demonstrated positive in vivo results in the mouse CaCl(2) arrhythmia model upon oral administration.
View Article and Find Full Text PDFGap junction pharmacology is a nascent field. Previous studies have identified molecules that enhance intercellular communication, and may offer potential for innovative antiarrhythmic therapy. However, their specific molecular target(s) and mechanism(s) of action remain unknown.
View Article and Find Full Text PDFRotigaptide (3) is an antiarrhythmic peptide that improves cardiac conduction by modifying gap-junction communication. Small molecule gap-junction modifiers with improved physical properties were identified from a Zealand Pharma peptide library using pharmaceutical profiling, established SAR around 3, and a putative pharmacophore model for rotigaptide. Activity of the compounds was confirmed in a mouse cardiac conduction block model of arrhythmia.
View Article and Find Full Text PDFPrevious studies suggest that dephosphorylation of connexin43 (Cx43) is related to uncoupling of gap junction communication, which plays an important role in the genesis of ischemia-induced ventricular tachycardia. We studied changes in Cx43 phosphorylation during global ischemia in the absence and presence of the antiarrhythmic peptide analogue rotigaptide (formerly known as ZP123). Phosphorylation analysis was performed on Cx43 purified from isolated perfused rat hearts using matrix-assisted laser desorption/ionization mass spectrometry and liquid chromatography electrospray ionization tandem mass spectrometry.
View Article and Find Full Text PDFThe antiarrhythmic and cardioprotective effect of increasing gap junction intercellular communication during ischemia/reperfusion injury has not been studied. The antiarrhythmic peptide rotigaptide (previously ZP123), which maintains gap junction intercellular communication, was tested in dogs subjected to a 60-min coronary artery occlusion and 4 h of reperfusion. Rotigaptide was administered i.
View Article and Find Full Text PDFAntiarrhythmic peptides such as AAP10 (Gly-Ala-Gly-4Hyp-Pro-Tyr-CONH(2)) have antiarrhythmic properties related to their stimulatory effect on gap junctional coupling. However, most of these peptides are not stable in enzymatic environment which limits studies with these compounds in vivo. ZP123 is a new antiarrhythmic peptide constructed using a retro-all-D-amino acid design of the AAP10 template (Ac-D-Tyr-D-Pro-D-4Hyp-Gly-D-Ala-Gly-NH(2)).
View Article and Find Full Text PDFWe characterized the novel, rationally designed peptide glucagon-like peptide 1 (GLP-1) receptor agonist H-HGEGTFTSDLSKQMEEEAVRLFIEWLKNGGPSSGAPPSK KKKKK-NH2 (ZP10A). Receptor binding studies demonstrated that the affinity of ZP10A for the human GLP-1 receptor was 4-fold greater than the affinity of GLP-1 (7-36) amide. ZP10A demonstrated dose-dependent improvement of glucose tolerance with an ED50 value of 0.
View Article and Find Full Text PDFAntiarrhythmic peptides (AAPs) are a group of compounds with antiarrhythmic properties; however, their use has been hampered by very low plasma stability. The aim of this study was to compare the in vitro and in vivo stability of our new stable AAP analog Ac-d-Tyr-d-Pro-d-Hyp-Gly-d-Ala-Gly-NH2 (ZP123) with the previously described AAP analog AAP10. Moreover, the effect of the two compounds was examined in a murine in vivo model of ouabain-induced second degree AV-block, and the effect on dispersion of action potential duration (APD dispersion) was studied during hypokalemic-ischemia in isolated perfused rabbit hearts.
View Article and Find Full Text PDF1 This study reports on the pharmacological characterization of ZP120, a novel ligand of the nociceptin/orphanin FQ (N/OFQ) peptide receptor, NOP. ZP120 is a structure inducing probes modified NOP ligand: Zealand Pharma proprietary SIP technology was used to increase the enzymatic stability and half-life of peptide. 2 In vitro, ZP120 mimicked the inhibitory effects of N/OFQ in the electrically stimulated mouse vas deferens, showing however higher potency (pEC(50) 8.
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