Search results for "phosphatidylserine"
showing 10 items of 55 documents
Removal of annexin V–positive sperm cells for intracytoplasmic sperm injection in ovum donation cycles does not improve reproductive outcome: a contr…
2014
Objective To determine the effect of removing presumptive apoptotic sperm cells from samples from unselected males by means of magnetic activated cell sorting (MACS) on live-birth delivery rates after intracytoplasmic sperm injection (ICSI) in couples undergoing ovum donation (OD). Design Prospective, randomized, triple-blinded, and controlled study. Setting Private university-affiliated IVF center. Patient(s) A total of 237 infertile couples undergoing ICSI as part of an OD program. Intervention(s) Semen specimens from the control group were prepared by swim-up. Samples from the study group were prepared by swim-up followed by MACS and incubation with annexin V–conjugated microbeads to rem…
Phosphatidylserine counteracts physiological and pharmacological suppression of humoral immune response
1990
Phosphatidylserine (PS) is a necessary cofactor for protein kinase C (PKC) activation, and changes in the synthesis of PS have been shown to participate in the mechanism(s) involved in the transmembrane signaling of interleukin 1 (IL-1). In view of the age-associated defects in T-cell functions, in the present study we have addressed the question of whether an in vivo treatment with PS might interfere with such processes. Furthermore, the effect of an in vitro treatment with PS in human peripheral blood monocytes (PBMC) or splenocytes activated with a lectin mitogen, on the expression of IL-2 receptor, was assessed. While the process of ageing was accompanied by a marked decline of humoral …
A novel compound of triphenyltin(IV) with N-tert-butoxycarbonyl-L-ornithine causes cancer cell death by inducing a p53-dependent activation of the mi…
2017
The triphenyltin(IV) compound with N-tert-butoxycarbonyl-L-ornithine (Boc-Orn-OH), [Ph3Sn(Boc-Orn-O)], was synthesized and characterized by elemental analysis, FT-IR, solution1H,13C and119Sn NMR and ESI mass spectrometry. The organotin(IV) compound inhibited at very low micromolar concentrations the growth of human tumor cell lines HepG2 (hepatocarcinoma cells), MCF-7 (mammary cancer) and HCT116 (colorectal carcinoma) while it did not affect the viability of non-malignant human-derived hepatic cells Chang. The mechanism of the antiproliferative effect of Ph3Sn(Boc-Orn-O), investigated on human hepatoma HepG2 cells, was pro-apoptotic, being associated with externalization of plasma membrane …
Membrane fluidity, membrane lipid pattern, and cytosolic Ca2+ content in platelets from a group of type II diabetic patients with macrovascular compl…
1995
OBJECTIVE To evaluate platelet membrane fluidity and some platelet metabolic parameters in type II diabetic patients with macrovascular complications. RESEARCH DESIGN AND METHODS In a group of 21 type II diabetic patients with macrovascular complications, we evaluated platelet membrane fluidity [marking intact resting platelets with the fluorescent probe 1,4-(trimethylamino)-phenyl-4-phenylhexatriene (TMA-DPH)], platelet membrane lipid pattern (cholesterol :phospholipid [C:PL] ratio and individual phospholipids), and platelet cytosolic Ca2+ content (marking intact resting platelets with the fluorescent probe Fura 2AM). RESULTS Platelet membrane fluidity is decreased in type II diabetic pat…
Sphingomyelin induces structural alteration in canine parvovirus capsid.
2007
One of the essential steps in canine parvovirus (CPV) infection, the release from endosomal vesicles, is dominated by interactions between the virus capsid and the endosomal membranes. In this study, the effect of sphingomyelin and phosphatidyl serine on canine parvovirus capsid and on the phospholipase A(2) (PLA(2)) activity of CPV VP1 unique N-terminus was analyzed. Accordingly, a significant (P< or =0.05) shift of tryptophan fluorescence emission peak was detected at pH 5.5 in the presence of sphingomyelin, whereas at pH 7.4 a similar but minor shift was observed. This effect may relate to the exposure of VP1 N-terminus in acidic pH as well as to interactions between sphingomyelin and CP…
Sphingomyelin inhibition of Ciona intestinalis (Tunicata) cytotoxic hemocytes assayed against sheep erythrocytes
1995
Hemocytes from the ascidian, Ciona intestinalis, are capable of lysing erythrocytes in vitro following cell membrane contact. With the aim of examining the mechanism of cytotoxicity, we performed inhibition experiments with lipid components of erythrocyte membranes. Cholesterol is not an inhibitor, whereas, among the phospholipids tested, (sphingomyelin, phosphatidylcholine, phosphatidylserine, phosphatidylethanolamine) sphingomyelin inhibits the hemolytic activity of hemocytes. However, thin layer chromatography showed that sphingomyelinase activity was not contained in the chloroform-methanol extracts from hemocyte debris. The inhibition capacity of the components ceramide and phosphorylc…
Synthesis, spectroscopic characterization and antiproliferative activity of two platinum(II) complexes containing N-donor heterocycles
2014
Abstract Novel mononuclear complexes of Pt(II), cis -[PtCl 2 (DMSO)HL]·2DMSO ( 1 ), where HL = 7-amino-2-(methylthio)[1,2,4]triazolo[1,5- a ]pyrimidine-6-carboxylic acid and Pt(bdt)Cl 2 ( 2 ), where bdt = [2,4-bis(5,6-diphenyl-1,2,4-triazin-3yl)-pyridine] have been synthesized and characterized by elemental analysis, IR and 1 H NMR spectroscopy and X-ray crystallography diffraction analyses. The molecular structure of ( 1 ) shows that Pt(II) ion has a square planar geometry with N(3) bonded heterocycle ligand, two cis chloride anions and S-bonded dimethylsulfoxide. The antiproliferative activity of complexes ( 1 ) and ( 2 ) has been tested in vitro against HepG2 human hepatoma cells and non…
Enhanced oxidative stress and increased mitochondrial mass during Efavirenz-induced apoptosis in human hepatic cells
2010
BACKGROUND AND PURPOSE Efavirenz (EFV) is widely used in the treatment of HIV-1 infection. Though highly efficient, there is growing concern about EFV-related side effects, the molecular basis of which remains elusive. EXPERIMENTAL APPROACH In vitro studies were performed to address the effect of clinically relevant concentrations of EFV (10, 25 and 50 mu M) on human hepatic cells. KEY RESULTS Cellular proliferation and viability were reduced in a concentration-dependent manner. Analyses of the cell cycle and several cell death parameters (chromatin condensation, phosphatidylserine exteriorization, mitochondrial proapoptotic protein translocation and caspase activation) revealed that EFV tr…
Hypercholesterolemic patients have higher eryptosis and erythrocyte adhesion to human endothelium independently of statin therapy
2021
BACKGROUND Phosphatidylserine (PS) externalization out of the membrane facilitates the eryptotic erythrocytes (EE) binding to endothelial cells (EC), potentially leading to atherosclerosis. Thus, the levels of eryptosis and interactions of EE-EC in hypercholesterolemic patients, either non-medicated or medicated, compared with healthy subjects were studied. METHODS A total of 56 subjects clustered into three groups: (control (n = 20), hypercholesterolemic non-treated (HCNT) (n = 15), and statin-treated (HCT) (n = 21)) were enrolled in this cross-sectional study. Biochemical parameters were determined with validated and standard methods. PS exposure was estimated from annexin-V-binding, cell…
Anti-Eryptotic Activity of Food-Derived Phytochemicals and Natural Compounds
2022
Human red blood cells (RBCs), senescent or damaged due to particular stress, can be removed by programmed suicidal death, a process called eryptosis. There are various molecular mechanisms underlying eryptosis. The most frequent is the increase in the cytoplasmic concentration of Ca2+ ions, later exposure of erythrocytes to oxidative stress, hyperosmotic shock, ceramide formation, stimulation of caspases, and energy depletion. Phosphatidylserine (PS) exposed by eryptotic RBCs due to interaction with endothelial CXC-Motiv-Chemokin-16/Scavenger-receptor, causes the RBCs to adhere to vascular wall with consequent damage to the microcirculation. Eryptosis can be triggered by various xenobiotics…