JAK4D, a first-in-class thyrotropin-releasing hormone (TRH)-based compound, is a prospective therapeutic candidate offering a multifaceted approach to treating neurodegeneration and other CNS conditions. The purpose of these studies was to determine the ability of JAK4D to bind to TRH receptors in human brain and to evaluate its neuropharmacological effects in neurodegenerative animal models. Additionally, JAK4D brain permeation was examined in mouse, and initial toxicology was assessed in vivo and in vitro.
View Article and Find Full Text PDFThe alpha-glucosidase inhibitors N-methyl-1-deoxynojirimycin (MDNJ) and castanospermine have been shown to inhibit angiogenesis. A hybrid of 1-deoxynojirimycin (DNJ) and an aryl-1,2,3-triazole, which inhibits both an alpha-glucosidase and methionine aminopeptidase-2 (MetAP2), displayed properties associated with inhibition of angiogenesis (Bioorg. Med.
View Article and Find Full Text PDFCannabinoid CB(1) receptors are highly expressed in the striatum where they are known to be co-localized with dopamine D(2) receptors. There is now strong evidence that cannabinoids modulate dopamine release in the brain. Using fast cyclic voltammetry, single pulse stimulation (0.
View Article and Find Full Text PDFHybrids of 1-deoxynojirimycin (DNJ) and aryl-1,2,3-triazole have been synthesized with a view to identifying an inhibitor of both alpha-glucosidase and methionine aminopeptidase 2 (MetAP2). One compound was a potent inhibitor of alpha-glucosidase at both the enzyme and cellular level, and this agent also inhibited bovine aortic endothelial cell (BAEC) growth and tube formation. The anti-proliferative activity of this hybrid is due to its ability to induce cell-cycle arrest in the G(1) phase.
View Article and Find Full Text PDFSynthesis of hybrids of 1-deoxynojirimycin (DNJ) and 5-aryl-1,2,3-triazole as potential bifunctional inhibitors of angiogenesis is described. The DNJ component inhibits the biosynthesis of cell surface oligosaccharides necessary for angiogenesis, whereas the aryl-1,2,3-triazole inhibits methionine aminopeptidase II, a target in angiogenesis therapy. One bifunctional compound was a more potent inhibitor of angiogenesis in vitro than DNJ alone or the 5-aryl-1,2,3-triazole alone.
View Article and Find Full Text PDFGlp-Asn-Pro-D-Tyr-D-TrpNH(2) is a novel synthetic peptide that mimics and amplifies central actions of thyrotropin-releasing hormone (TRH) in rat without releasing TSH. The aim of this study was to compare the binding properties of this pentapeptide and its all-L counterpart (Glp-Asn-Pro-Tyr-TrpNH(2)) to TRH receptors in native rat brain tissue and cells expressing the two TRH receptor subtypes identified in rat to date, namely TRHR1 and TRHR2. Radioligand binding studies were carried out using [(3)H][3-Me-His(2)]TRH to label receptors in hippocampal, cortical and pituitary tissue, GH4 pituitary cells, as well as CHO cells expressing TRHR1 and/or TRHR2.
View Article and Find Full Text PDFBackground: The inhibition of angiogenesis, defined as the process of new blood vessel formation, represents a promising strategy for treating cancer.
Materials And Methods: The inhibitory properties of two N-(per-O-acetylated-beta-D- mannopyranosyl)thiophene-2-carboxamides derivatives (AMTCs, [1],[2]), N-(2,3,4,6-tetra-O-ethoxycarbonyl-beta-D-mannopyranosyl)- thiophene-2-carboxamide [3] and of 2,3,4,6-tetra-O-acetyl-beta-D-mannopyranosyl-acetamide [4] on the growth of bovine aortic endothelial cells (BAECs) induced by basic fibroblast growth factor (bFGF) were assessed using a [3H]thymidine incorporation assay. The cellular uptake of AMTCs and the non-acetylated homologue (MTC) into BAEC were compared using mass spectrometry analysis of cell lysates.
Thyrotropin-releasing hormone (TRH) displays multiple CNS-mediated actions that have long been recognized to have therapeutic potential in treating a wide range of neurological disorders. Investigations of CNS functions and clinical use of TRH are hindered, however, due to its rapid degradation by TRH-degrading ectoenzyme (TRH-DE). We now report the discovery of a set of first-in-class compounds that display unique ability to both potently inhibit TRH-DE and bind to central TRH receptors with unparalleled affinity.
View Article and Find Full Text PDFA range of N-glycosyl-thiophene-2-carboxamides, including a 6H-thieno[2,3-c]pyridin-7-one and a bivalent compound, have been synthesised and assayed for their effects on DNA synthesis in bovine aortic endothelial cells or on the growth of synoviocytes. Per-O-acetylated analogues of the glycoconjugates were significantly more effective inhibitors when compared to their corresponding non-acetylated analogues, indicating that the lower potency observed for hydroxylated derivatives is due to less efficient transport of these compounds across the cell membrane. Thiophene-2-carboxamide was inactive as an inhibitor of bFGF induced proliferation, confirming the requirement of the carbohydrate residue for the observed biological properties.
View Article and Find Full Text PDFInhibitors of endothelial cell proliferation are of interest in development of therapies for angiogenesis related disease. N-Glucosyl-thiophene-2-carboxamides have been synthesized and evaluated for their effects on proliferation in bovine aortic endothelial cells. Per-O-acetylated-N-glucosyl-thiophene-2-carboxamides showed improved inhibition of both serum and bFGF stimulated uptake of [(3)H]thymidine, when compared to non-acetylated analogues.
View Article and Find Full Text PDFThe disaccharide beta-D-GlcA-(1-->4)-alpha-D-GlcNAc-1-->OMe and other small nonsulfated oligosaccharides related to heparin/heparan sulfate have been shown to bind to FGF and activated the fibroblast growth factor (FGF) signalling pathway in (F32) cells expressing the FGF receptor. Synthetic routes to beta-D-GlcA-(1-->4)-alpha-D-GlcNAc-1-->OMe and a glucose analogue beta-D-Glc-(1-->4)-alpha-D-GlcNAc-1-->OMe are described. The effects of these disaccharides on endothelial cell growth, which is relevant to angiogenesis, were evaluated and it was found they did not mimic the inhibitory effects that were observed for heparin albumin (HA) and that have also been observed by monosaccharide conjugates.
View Article and Find Full Text PDFCompounds that alter endothelial cell growth are of interest in the development of angiogenesis modulators. A structurally diverse series of saccharide derivatives (glycosylamide conjugates) have been synthesized and evaluated for their effects on bovine aortic endothelial cell (BAEC) growth. Heparin-albumin (HA) reduced BAEC growth by 32% at 10 microg/mL and a number of the novel saccharide conjugates from the library were found to mimic the effect of HA as they also inhibit endothelial cell survival under identical conditions.
View Article and Find Full Text PDFInhibitors of FGF-2 binding to a heparin-albumin conjugate were identified by ELISA from a library of glucuronic acid derivatives. These compounds were also inhibitors of endothelial cell survival that is dependant on FGF-2 and heparin or heparan sulfate proteoglycans. The results indicate that these bioactive compounds may prove useful as lead structures for the further development of pharmaceutical agents capable of modulating biological activity of FGF-2.
View Article and Find Full Text PDFWe have used a directed peptide library, in which the histidyl residue of thyrotropin-releasing hormone (TRH) was systematically replaced by a series of 24 natural and unnatural amino acids, to characterise TRH binding sites in rat brain cortex. This was achieved by measuring the ability of library peptides to compete with [3H][3-Me-His(2)]TRH or [3H]TRH binding to rat cortical homogenates. [3H][3-Me-His(2)]TRH was observed to bind to a single population of high-affinity, low-capacity sites (K(d): 4.
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