The goal of the present work was to develop novel β-substituted-α-halomethyl acrylates from a methodology in an aqueous phase and to evaluate their bioactivity as potential inhibitors of mast cell activation. Eleven β-substituted-α-halomethyl acrylates were synthesized through a modified Horner-Wadsworth-Emmons reaction. Compound 48/80 and the calcium ionophore A23187 stimulated the release of β-hexosaminidase from mast cells.
View Article and Find Full Text PDFA library of structurally related coumarins was generated through synthesis reactions and chemical modification reactions to obtain derivatives with antiproliferative activity both and . Out of a total of 35 structurally related coumarin derivatives, seven of them showed inhibitory activity in tests against DNA polymerase with IC values lower than 250 μM. The derivatives 4-(chloromethyl)-5,7-dihydroxy--chromen-2-one () and 4-((acetylthio)methyl)-2-oxo--chromen-7-yl acetate () showed the most promising anti-polymerase activity with IC values of 20.
View Article and Find Full Text PDFGlioblastoma (GBM) is the most common and fatal primary tumor of the central nervous system (CNS) and current treatments have limited success. Chemokine signaling regulates both malignant cells and stromal cells of the tumor microenvironment (TME), constituting a potential therapeutic target against brain cancers. Here, we investigated the C-C chemokine receptor type 7 (CCR7) and the chemokine (C-C-motif) ligand 21 (CCL21) for their expression and function in human GBM and then assessed their therapeutic potential in preclinical mouse GBM models.
View Article and Find Full Text PDFIn this study, we investigated the effects of eleven synthetic guanidines containing the 1,3-diphenylpropenone core on the viabilities of six human cancer cells. The most cytotoxic compound against human cancer cells of this series contains a -tosyl group and a -methylpiperazine moiety . It was cytotoxic against leukemia cells (U-937, HL-60, MOLT-3, and NALM-6) with significant effects against Bcl-2-overexpressing U-937/Bcl-2 cells as well as the human melanoma SK-MEL-1 cell line.
View Article and Find Full Text PDFSynthetic flavonoids with new substitution patterns have attracted attention as potential anticancer drugs. Here, twelve chalcones were synthesized and their antiproliferative activities against five human tumour cells were evaluated. This series of chalcone derivatives was characterized by the presence of an additional aromatic or heterocyclic ring linked by an ether, in the case of a benzyl radical, or an ester or amide functional group in the case of a furoyl radical.
View Article and Find Full Text PDFBackground: Metabolic syndrome (MS) is defined as a low-grade proinflammatory state in which abnormal metabolic and cardiovascular factors increase the risk of developing cardiovascular disease and neuroinflammation. Events, such as the accumulation of visceral adipose tissue, increased plasma concentrations of free fatty acids, tissue hypoxia, and sympathetic hyperactivity in MS may contribute to the direct or indirect activation of Toll-like receptors (TLRs), specifically TLR4, which is thought to be a major component of this syndrome. Activation of the innate immune response via TLR4 may contribute to this state of chronic inflammation and may be related to the neuroinflammation and neurodegeneration observed in MS.
View Article and Find Full Text PDFScientific literature is inundated with secondary metabolites from marine sources. In this ocean of natural products, the presence of recurring patterns has traditionally led scientists to unravel the biosynthetic mechanisms that naturally yield these products, as well as to imitate Nature to prepare them in the laboratory, especially when promising bioactivities and stimulating molecular architectures are involucrate. For instance, natural products containing multisubstituted oxygenated rings and macrocyclic lactones are recurrently selected as targets for developing total syntheses.
View Article and Find Full Text PDFLysophosphatidic acid (LPA) is an abundant bioactive phospholipid, with multiple functions both in development and in pathological conditions. Here, we review the literature about the differential signaling of LPA through its specific receptors, which makes this lipid a versatile signaling molecule. This differential signaling is important for understanding how this molecule can have such diverse effects during central nervous system development and angiogenesis; and also, how it can act as a powerful mediator of pathological conditions, such as neuropathic pain, neurodegenerative diseases, and cancer progression.
View Article and Find Full Text PDFBackground: DNA methylation has emerged as an important epigenetic regulator of brain processes, including circadian rhythms. However, how DNA methylation intervenes between environmental signals, such as light entrainment, and the transcriptional and translational molecular mechanisms of the cellular clock is currently unknown. Here, we studied the after-hours mice, which have a point mutation in the Fbxl3 gene and a lengthened circadian period.
View Article and Find Full Text PDFStress inducible protein 1 (STI1) is a co-chaperone acting with Hsp70 and Hsp90 for the correct client proteins' folding and therefore for the maintenance of cellular homeostasis. Besides being expressed in the cytosol, STI1 can also be found both in the cell membrane and the extracellular medium playing several relevant roles in the central nervous system (CNS) and tumor microenvironment. During CNS development, in association with cellular prion protein (PrP), STI1 regulates crucial events such as neuroprotection, neuritogenesis, astrocyte differentiation and survival.
View Article and Find Full Text PDFBackground: Brain circulation disorders such as chronic cerebral hypoperfusion have been associated with a decline in cognitive function during the development of dementia. Astrocytes together with microglia participate in the immune response in the CNS and make them potential sentinels in the brain parenchyma. In addition, astrocytes coverage integrity has been related to brain homeostasis.
View Article and Find Full Text PDFSynthetic flavonoids containing a naphthalene ring have attracted attention as potential cytotoxic compounds. Here, we synthesized ten chalcones and their corresponding flavanones and evaluated their antiproliferative activity against the human tumour cell line U-937. This series of chalcone derivatives was characterized by the presence of a naphthalene ring which was kept unaltered- and attached to the β carbon of the 1-phenyl-2-propen-1-one framework.
View Article and Find Full Text PDFHuman papilloma virus oncogenes and estradiol are major etiologic factors associated with cervical cancer. In order to understand the mechanism by which these two factors promote carcinogenesis, the role of the Hedgehog (Hh) signaling pathway was evaluated during the normal growth of cervical epithelium and in the presence of E6/E7 oncogenes and exogenous estradiol. Hh signaling activity was determined in live animals (i.
View Article and Find Full Text PDFThe relationship between the mechanisms that underlie longevity and aging and the metabolic alterations due to feeding conditions has not been completely defined. In the present work, through the deletion of the gene encoding catalase, hydrogen peroxide (HO) was uncovered as a relevant regulator of longevity and of liver metabolism. Mice lacking catalase (Cat) fed ad libitum with a regular diet showed a shorter lifespan than wild type mice, which correlated with reduced body weight, blood glucose levels and liver fat accumulation, but not with increased oxidative damage or consistent premature aging.
View Article and Find Full Text PDFGlioblastoma (GBM) is the most common and fatal primary malignant brain tumor. Despite advances in the understanding of the biology of gliomas, little has changed in the treatment of these tumors in the past decade. Phase III clinical trials showed no benefit for the use of bevacizumab in newly diagnosed patients, leading to a renewed search for new antiangiogenic drugs, as well as immunotherapeutic approaches, including checkpoint inhibitors, chimeric antigen receptor T cells, and intracerebral CpG-oligodeoxynucleotides.
View Article and Find Full Text PDFDetermination of cellular signaling in live embryos is key to understand the molecular processes that drive development. Here, we show that a transgenic mouse line carrying a luciferase-based gene reporter of Gli-mediated transcriptional activation (Gli-Luc) displays sonic hedgehog (Shh) signaling in discrete developmental processes during short-term cultures of whole embryos or embryo explants. The bioluminescence in E9.
View Article and Find Full Text PDFA direct and general method for the synthesis of naturally occurring 2,3,4,5,6-pentasubstituted tetrahydropyrans has been developed, employing β,γ-unsaturated N-acyl oxazolidin-2-ones as key starting materials. The combination of the Evans aldol addition and the Prins cyclization allowed the diastereoselective and efficient generation of the desired oxacycles in two fashions: a one-pot Evans aldol-Prins protocol, in which five new σ bonds and five contiguous stereocenters were straightforwardly generated, and a two-step version, which additionally permitted the isolation of β,γ-unsaturated alcohol precursors bearing an N-acyl oxazolidin-2-one in the α position. From these alcohols were also obtained halogenated pentasubstituted tetrahydropyrans as well as 2,3,4,5-tetrasubstituted tetrahydrofurans, shedding light on the mechanism of the process.
View Article and Find Full Text PDFFlavonoids are phenolic substances that appear to exert beneficial effects in several chronic diseases, including cancer. Structure-activity relationships of the cytotoxic activity of a series of flavonols and their 3-methyl ether derivatives established that 3'-hydroxy-3,4'-dimethoxyflavone (flavonoid 11) displayed strong cytotoxicity against human leukaemia cell lines (HL-60, U-937 and MOLT-3), and cells that over-express the anti-apoptotic proteins, Bcl-2 and Bcl-x, and against P-glycoprotein-overexpressing K-562/ADR cells. This compound induced G-M cell cycle arrest and it was a potent apoptotic inducer on HL-60, MOLT-3, U-937 and U-937/Bcl-2 cell lines.
View Article and Find Full Text PDFFlavonoids are naturally occurring polyphenolic compounds and are among the most promising anticancer agents. A series of flavonols and their 3-methyl ether derivatives were synthesized and assessed for cytotoxicity. It was found that 3'-hydroxy-3,4'-dimethoxyflavone (flavonoid 7a) displayed strong cytotoxicity against human SK-MEL-1 melanoma cells and blocked tubulin polymerization, but had no significant cytotoxic effects against quiescent or proliferating human peripheral blood mononuclear cells.
View Article and Find Full Text PDFGlioblastoma is a malignant tumor of astrocytic origin that is highly invasive, proliferative and angiogenic. Despite current advances in multimodal therapies, such as surgery, radio- and chemotherapy, the outcome for patients with glioblastoma is nearly always fatal. The glioblastoma microenvironment has a tremendous influence over the tumor growth and spread.
View Article and Find Full Text PDFFlavonoids have attracted great interest due to their possible anticancer activities. Here we investigated the antiproliferative activity of the flavonoids isolated from Baccharis scandens against human leukemia cell lines and found that the methoxyflavonoid gardenin B was the most cytotoxic compound against HL-60 and U-937 cells, showing IC50 values between 1.6 and 3.
View Article and Find Full Text PDFA general and stereoselective method to synthesize 2,3,4,5,6-pentasubstituted tetrahydropyrans in three steps starting from three different aldehydes is described. Key substrates β,γ-unsaturated N-acyloxazolidin-2-ones were subjected to an "Evans Aldol-Prins" protocol to generate five σ-bonds and five stereocenters in only a one-pot process with yields up to 60% and excellent stereoselectivities.
View Article and Find Full Text PDFThe chemical study of the red alga Laurencia viridis has led to the isolation of four new polyether triterpenoids: 28-hydroxysaiyacenol B (2), saiyacenol C (3), 15,16-epoxythyrsiferol A (4), and 15,16-epoxythyrsiferol B (5). The structures of 2 and 3 were established mainly by NMR data analysis and comparison with the well-known metabolite dehydrothyrsiferol (1). However, due to the existence of a nonprotonated carbon within the epoxide functionality, stereochemical assignments in 4 and 5 required an in-depth structural study that included NOESY data, J-based configuration analysis, comparison with synthetic models, and DFT calculations.
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