Background: Hypoparathyroidism-retardation-dysmorphism (HRD) syndrome is a disease composed of hypoparathyroidism, growth retardation, severe developmental delay, and typical dysmorphic features caused by the tubulin-specific chaperone E gene variant. Many patients succumb in infancy to HRD due to overwhelming infections mainly caused by Pneumococcus spp. Knowledge related to the immune system in these patients is scarce.
View Article and Find Full Text PDFBackground: Previous studies have demonstrated that cytosolic phospholipase Aα (cPLAα) is required for NOX2 NADPH oxidase activation in human and mouse phagocytes. Moreover, upon stimulation, cPLAα translocates to the plasma membranes by binding to the assembled oxidase, forming a complex between its C2 domain and the PX domain of the cytosolic oxidase factor, p47 in human phagocytes. Intravenous administration of antisense against cPLAα that significantly inhibited its expression in mouse peritoneal neutrophils and macrophages also inhibited superoxide production, in contrast to cPLAα knockout mice that showed normal superoxide production.
View Article and Find Full Text PDFBackground: Amyotrophic lateral sclerosis (ALS) is a fatal multifactorial neurodegenerative disease characterized by the selective death of motor neurons. Cytosolic phospholipase A alpha (cPLAα) upregulation and activation in the spinal cord of ALS patients has been reported. We have previously shown that cPLAα upregulation in the spinal cord of mutant SOD1 transgenic mice (SOD1) was detected long before the development of the disease, and inhibition of cPLAα upregulation delayed the disease's onset.
View Article and Find Full Text PDFCollagen is the major structural protein in the extracellular matrix of skin produced by fibroblasts. UV exposure results in infiltration of neutrophils within the epidermis and dermis, inducing collagen damage and contributing to the process of photo-aging. Collagen-3 is an integral structural component with collagen-1, and is an important regulator of collagen-1 fibrillogenesis.
View Article and Find Full Text PDFBiallelic mutations in the zeta-associated protein 70 (ZAP70) gene cause combined immunodeficiency (CID). Neonatal screening for severe CID in Israel is implemented since 2015. We report on clinical, flow cytometry, and genetic data of an unusual ZAP70 deficiency patient.
View Article and Find Full Text PDFNeutrophil chemotactic defects have been reported previously in patients with hyper-IgE syndrome. Bi-allelic mutations in dedicator of cytokinesis 8 (DOCK8) gene usually cause an autosomal recessive hyper-IgE syndrome phenotype. Data are lacking about expression of DOCK8 protein in neutrophils or the possible role of DOCK8 in neutrophil function.
View Article and Find Full Text PDFMicroglia activation toward the M1 phenotype has been reported to contribute to the neurodegenerative processes and cognition alterations due to the release of pro-inflammatory mediators and cytokines. The aim of the present research was to assess the effectiveness of free fatty acids omega-3 preparations: eicosapentaenoic acid (EPA) or/and docosahexaenoic acid (DHA), carotenoids and phenolics combinations, in inhibiting the release of inflammatory mediators from activated microglia. Preincubation of BV-2 microglia cells with each of the FFAs omega-3 preparations in a range of 0.
View Article and Find Full Text PDFJ Neuroinflammation
February 2017
Background: The aberrant expression of CD40, a co-stimulatory receptor found on the antigen-presenting cells, is involved in the pathogenesis of various degenerative diseases. Our previous study demonstrated that the reduction of cytosolic phospholipase A alpha (cPLAα) protein overexpression and activation in the spinal cord of a mouse model of ALS, hmSOD1 G93A, inhibited CD40 upregulation in microglia. The present study was designed to determine whether cPLAα has a direct, participatory role in the molecular events leading to CD40 induction.
View Article and Find Full Text PDFMutations in the dedicator of cytokinesis 8 (DOCK8) gene cause a combined immunodeficiency usually diagnosed as autosomal recessive hyper IgE syndrome. We sought to reveal the varying manifestations in patients with a unique mutation in DOCK8 gene by a retrospective medical record review. Ten patients from five consanguineous families and three tribes were included.
View Article and Find Full Text PDFBackground: Amyotrophic lateral sclerosis (ALS) is a fatal multifactorial neurodegenerative disease characterized by selective death of motor neurons in the cortex, brainstem, and spinal cord. Cytosolic phospholipase A2 alpha (cPLA2α) upregulation and activation in the spinal cord of patients with sporadic ALS and in the spinal cord of human mutant SOD1G93A (hmSOD1) transgenic mice were recently reported.
Methods: cPLA2α upregulation in the brainstem and spinal cord was reduced by brain infusion of a specific antisense oligonucleotide against cPLA2α (AS), and the effect was evaluated on disease progression and brain cell activation.
Colitis, an inflammation of the colon, is a well-characterized massive tissue injury. Cytosolic phospholipase A2 α (cPLA2 α) upregulation plays an important role in the development of several inflammatory diseases. The aim of the present study was to define the role of cPLA2 α upregulation in the development of colitis.
View Article and Find Full Text PDFAmyloid-β peptides generated by proteolysis of the β-amyloid precursor protein (APP) play an important role in the pathogenesis of Alzheimer's disease. The present study aimed to determine whether cytosolic phospholipase A2 α (cPLA2 α) plays a role in elevated APP protein expression induced by aggregated amyloid-β1-42 (Aβ) in cortical neurons and to elucidate its specific role in signal events leading to APP induction. Elevated cPLA2 α and its activity determined by phosphorylation on serine 505 as well as elevated APP protein expression, were detected in primary rat cortical neuronal cultures exposed to Aβ for 24 h and in cortical neuron of human amyloid-β1-42 brain infused mice.
View Article and Find Full Text PDFPurpose: The role of the Bruton tyrosine kinase (Btk) protein in neutrophil function has been evaluated using neutrophils from healthy volunteers after incubation with a Btk inhibitor, leflunomide metabolite analog (LFM-A13), suggesting an important role for Btk in neutrophil function. We sought to determine the role of Btk protein on neutrophil superoxide generation and chemotaxis stimulated by N-formyl-methionine-leucine-phenylalanine (fMLP).
Methods: Chemotaxis was assayed on agarose gel and superoxide generation by cytochrome C reduction.
Increased cytosolic phospholipase A2α (cPLA2α) immunoreactivity and transcript were observed in Alzheimer's disease (AD) brain associated with amyloid deposits. Thus, the present study examined whether cPLA2α upregulation participate in cortical neuron damage induced by aggregated Aβ1-42 and determined its role in the signaling events leading to damage, using an antisense technology. Exposure of primary cortical neurons to 1μM aggregated Aβ1-42 for 24h induced up-regulation and activation of cPLA2α and apoptotic cell death of about 30% as detected by: cell count, MTT reduction, caspases-3 and -8 activation, DAPI and TUNEL staining, that were prevented by inhibition of cPLA2α up-regulation and activity in the presence of antisense against cPLA2α (AS).
View Article and Find Full Text PDFIn established obesity, inflammation and macrophage recruitment likely contribute to the development of insulin resistance. In the current study, we set out to explore whether adipose tissue infiltration by neutrophils that occurs early (3 days) after initiating a high-fat diet (HFD) could contribute to the early occurrence of hepatic insulin resistance and to determine the role of cytosolic phospholipase A2α (cPLA2α) in this process. The 3-day HFD caused a significant upregulation of cPLA2α in periepididymal fat and in the liver.
View Article and Find Full Text PDFInflammatory mediators and cytokines play important roles in the pathogenesis of a vast number of human diseases; therefore much attention is focused on blunting their proinflammatory modes of action. The aims of the present research were to assess the effectiveness of combinations of carotenoids and phenolics, at concentrations that can be achieved in blood, to inhibit the release of inflammatory mediators from macrophages exposed to lipopolysaccharide (LPS) and to determine what the anti-inflammatory effect of the phytonutrient combinations was in an in vivo mouse model of peritonitis. Preincubation of mouse peritoneal macrophages with lycopene (1 μM) or Lyc-O-Mato (1 μM) and carnosic acid (2 μM), lutein (1 μM), and/or β-carotene (2 μM) 1h before addition of LPS for 24 h caused a synergistic inhibition of NO, prostaglandin E(2), and superoxide production derived from downregulation of iNOS, COX-2, and NADPH oxidase protein and mRNA expression and synergistic inhibition of TNFα secretion.
View Article and Find Full Text PDFCytosolic phospholipase A(2)α (cPLA(2)α) up-regulation has been reported in human colorectal cancer cells, thus we aimed to elucidate its role in the proliferation of the human colorectal cancer cell line, HT-29. EGF caused a rapid activation of cPLA(2)α which coincided with a significant increase in cell proliferation. The inhibition of cPLA(2)α activity by pyrrophenone or by antisense oligonucleotide against cPLA(2)α (AS) or inhibition of prostaglandin E(2) (PGE(2)) production by indomethacin resulted with inhibition of cell proliferation, that was restored by addition of PGE(2).
View Article and Find Full Text PDFThe regulated expression of ICAM-1 plays an important role in inflammatory processes and immune responses. The present study aimed to determine the in vivo involvement of cytosolic phospholipase A(2)α (cPLA(2)α) in ICAM-1 overexpression during inflammation and to elucidate the cPLA(2)α-specific role in signal events leading to ICAM-1 upregulation in endothelial cells. cPLA(2)α and ICAM-1 upregulation were detected in inflamed paws of mice with collagen-induced arthritis and in periepididymal adipose tissue of mice fed a high-fat diet.
View Article and Find Full Text PDFA 1926-ins-T mutation in the TrkA gene encoding the tyrosine kinase receptor for nerve growth factor (NGF) was previously documented in patients with congenital insensitivity to pain with anhidrosis (CIPA). These patients suffer from skin lacerations which often evolve into deep tissue infections. Abnormality in neutrophil functions may explain this high rate of severe infections.
View Article and Find Full Text PDFCytosolic phospholipase A2alpha (cPLA2) plays an important role in the development of several inflammatory diseases. The aim of the present study is to determine whether inhibition of cPLA2 expression, using specific antisense oligonucleotides against cPLA2 (antisense), is efficient in reducing inflammation after its development. Two mouse models of inflammation were included in the study: thioglicolate peritonitis and collagen-induced arthritis (CIA).
View Article and Find Full Text PDFWe have previously demonstrated a physical interaction between cytosolic phospholipase A2alpha (cPLA2) and the assembled NADPH oxidase on plasma membranes following neutrophil stimulation. The aim of the present study was to define the exact binding sites between these two enzymes. Here we show, based on blot overlay experiments, Förster resonance energy transfer analysis and studies in neutrophils from patients with chronic granulomatous disease deficient in p67phox or p47phox, that cPLA2 specifically binds to p47phox and that p47phox is sufficient to anchor cPLA2 to the assembled oxidase on the plasma membranes upon stimulation.
View Article and Find Full Text PDFChronic inflammation of adipose tissue in obesity is by now an established phenomenon, but the initiating event(s) of the inflammatory cascade are still unknown. We hypothesized that neutrophil infiltration into adipose tissue may precede macrophage infiltration as in classical immune responses. Here we demonstrate that early (3 and 7 days) after initiating high-fat feeding of C57BL/6J mice, neutrophils transiently infiltrate the parenchyma of intra-abdominal adipose tissue.
View Article and Find Full Text PDFImpairment of neutrophil functions and high levels of apoptotic neutrophils have been reported in human immunodeficiency virus (HIV) patients. The aim of the present study was to investigate the direct in vitro effects of the different HIV protease inhibitors (PIs) on neutrophil functions and apoptosis and to explore their mechanisms of action. The effects of nelfinavir (NFV), saquinavir (SQV), lopinavir (LPV), ritonavir (RTV), and amprenavir (APV) in the range of 5 to 100 microg/ml on neutrophil function, apoptosis, and mu-calpain activity were studied.
View Article and Find Full Text PDFHypoparathyroidism, retardation, and dysmorphism (HRD) syndrome is the first reported disease caused by a defect in the tubulin folding and assembly pathway. We aimed to summarize our experience with a cohort of patients with HRD, analyze their growth, and evaluate patients' polymorphonuclear cell (PMN) functions. The records of 22 HRD patients in a single medical center were reviewed.
View Article and Find Full Text PDFVitamin B(12) deficiency is a well-known cause of recurrent aphthous stomatitis (RAS). However, the mechanism by which this deficiency causes the stomatitis is not well understood. Imerslund-Grasbeck syndrome (IGS) causes vitamin B(12) deficiency and proteinuria due to a defect in the vitamin B(12) receptor.
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