65 research outputs found

    Sodium Ascorbate induces apoptosis in neuroblastoma cell lines by interfering with iron uptake

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Neuroblastoma (NB) is an extra-cranial solid tumour of childhood. In spite of the good clinical response to first-line therapy, complete eradication of NB cells is rarely achieved. Thus, new therapeutic strategies are needed to eradicate surviving NB cells and prevent relapse. Sodium ascorbate has been recently reported to induce apoptosis of B16 melanoma cells through down-regulation of the transferrin receptor, CD71. Since NB and melanoma share the same embryologic neuroectodermal origin, we used different human NB cell lines to assess whether the same findings occurred.</p> <p>Results</p> <p>We could observe dose- and time-dependent induction of apoptosis in all NB cell lines. Sodium ascorbate decreased the expression of CD71 and caused cell death within 24 h. An increase in the global and specific caspase activity took place, as well as an early loss of the mitochondrial transmembrane potential. Moreover, intracellular iron was significantly decreased after exposure to sodium ascorbate. Apoptotic markers were reverted when the cells were pretreated with the iron donor ferric ammonium citrate (FAC), further confirming that iron depletion is responsible for the ascorbate-induced cell death in NB cells.</p> <p>Conclusion</p> <p>Sodium ascorbate is highly toxic to neuroblastoma cell lines and the specific mechanism of vitamin C-induced apoptosis is due to a perturbation of intracellular iron levels ensuing TfR-downregulation.</p

    Ferritin heavy chain Is the host factor responsible for HCV-Induced inhibition of apoB-100 production and is required for efficient viral infection

    Get PDF
    Hepatic fat export occurs by apolipoprotein B-100-containing lipoprotein production, whereas impaired production leads to liver steatosis. Hepatitis C virus (HCV) infection is associated to dysregulation of apoB-100 secretion and steatosis; however, the molecular mechanism by which HCV affects the apoB-100 secretion is not understood. Here, combining quantitative proteomics and computational biology, we propose ferritin heavy chain (Fth) as being the cellular determinant of apoB-100 production inhibition. By means of molecular analyses, we found that HCV nonstructural proteins and NS5A appear to be sufficient for inducing Fth up-regulation. Fth in turn was found to inhibit apoB-100 secretion leading to increased intracellular degradation via proteasome. Notably, intracellular Fth down-regulation by siRNA restores apoB-100 secretion. The inverse correlation between ferritin and plasma apoB-100 concentrations was also found in JFH-1 HCV cell culture systems (HCVcc) and HCV-infected patients. Finally, Fth expression was found to be required for robust HCV infection. These observations provide a further molecular explanation for the onset of liver steatosis and allow for hypothesizing on new therapeutic and antiviral strategies

    Characterization and Comparison of Ocular Surface Microbiome in Newborns

    Get PDF
    The ocular microbiome is of fundamental importance for immune eye homeostasis, and its alteration would lead to an impairment of ocular functionality. Little evidence is reported on the composition of the ocular microbiota of term infants and on the impact of antibiotic prophylaxis. Methods: A total of 20 conjunctival swabs were collected from newborns at birth and after antibiotic treatment. Samples were subjected to 16S rRNA sequencing via system MiSeq Illumina. The data were processed with the MicrobAT software and statistical analysis were performed using two-way ANOVA. Results: Antibiotic prophylaxis with gentamicin altered the composition of the microbiota. In detail, a 1.5- and 2.01-fold reduction was recorded for Cutibacterium acnes (C. acnes) and Massilia timonae (M. timonae), respectively, whereas an increase in Staphylococcus spp. of 6.5 times occurred after antibiotic exposure. Conclusions: Antibiotic prophylaxis altered the ocular microbiota whose understanding could avoid adverse effects on eye health

    Early and extended erythropoietin monotherapy after hypoxic ischaemic encephalopathy:a multicentre double-blind pilot randomised controlled trial

    Get PDF
    Objective: To examine the feasibility of early and extended erythropoietin monotherapy after hypoxic ischaemic encephalopathy (HIE). Design: Double-blind pilot randomised controlled trial.Setting: Eight neonatal units in South Asia. Patients: Neonates (≥36 weeks) with moderate or severe HIE admitted between 31 December 2022 and 3 May 2023. Interventions: Erythropoietin (500 U/kg daily) or to the placebo (sham injections using a screen) within 6 hours of birth and continued for 9 days. MRI at 2 weeks of age. Main outcomes and measures: Feasibility of randomisation, drug administration and assessment of brain injury using MRI. Results: Of the 154 neonates screened, 56 were eligible; 6 declined consent and 50 were recruited; 43 (86%) were inborn. Mean (SD) age at first dose was 4.4 (1.2) hours in erythropoietin and 4.1 (1.0) hours in placebo. Overall mortality at hospital discharge occurred in 5 (19%) vs 11 (46%) (p=0.06), and 3 (13%) vs 9 (40.9%) (p=0.04) among those with moderate encephalopathy in the erythropoietin and placebo groups. Moderate or severe injury to basal ganglia, white matter and cortex occurred in 5 (25%) vs 5 (38.5%); 14 (70%) vs 11 (85%); and 6 (30%) vs 2 (15.4%) in the erythropoietin and placebo group, respectively. Sinus venous thrombosis was seen in two (10%) neonates in the erythropoietin group and none in the control group. Conclusions: Brain injury and mortality after moderate or severe HIE are high in South Asia. Evaluation of erythropoietin monotherapy using MRI to examine treatment effects is feasible in these settings. Trial registration number: NCT05395195

    Genome-wide expression in neonatal encephalopathy

    No full text
    Developing new treatments for babies with birth asphyxia related brain injury (neonatal encephalopathy) and preventing cerebral palsy is hampered by two major roadblocks. Firstly, different babies with birth asphyxia may appear clinically similar, but their brain injury may be due to different underlying reasons and they may have different outcomes. Secondly, it takes several years before the impact of brain injury becomes measurable through clinical testing. In my thesis, I examine two key hypotheses (a) cerebral magnetic resonance biomarkers during the neonatal period can accurately predict neurodevelopmental outcomes at 2 years following therapeutic hypothermia for neonatal encephalopathy (b) neonatal encephalopathy is associated with a unique host gene expression profile at the time of birth.Open Acces
    • …
    corecore