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

<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

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

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

The 2004 probabilistic seismic hazard assessment for the Italian area

We present an initiative aimed at fulfilling the requirement of the Ordnance 3274 (20 March 2003, Annex 1) of the Italian Prime Minister. This law established that a new seismic hazard map of the Italian territory be prepared within one year (April 2004) and stated the general compilation criteria. To comply with this request, INGV involved scientists and engineers from Italian scientific institutions along with its own researchers. Despite the tight schedule, the initiative utilised and further elaborated original information and knowledge acquired during the past few years. In particular, we compiled a new set of source zones (ZS9) - acknowledging new evidence of active faulting and recently acquired evaluations on seismogenic potential - and a new earthquake catalogue (CPTI04) extended to 2002. A limited-scale logical tree approach was adopted to explore epistemic uncertainties related to: i) the assessment of catalogue completeness based on historical and statistical methods; ii) the evaluation of seismicity rates, based on activity rates and G-R rates; iii) the assessment of Mmax, partly constrained by geological evidence; iv) the ground-motion attenuation models, where regional relationships have been used to complement the classical European and Italian relationships. The results consists of a map displaying the median values of 16 weighted branches in terms of PGA with 10% exceedance probability in 50 years, related to very stiff soil conditions. Although in many steps we made conservative choices, the resulting PGA distribution exhibits lower maximum values with respect to previous country-scale hazard maps. This is mainly due to: a) magnitude re-assessment; b) larger size of the source zones; c) more realistic completeness time-intervals; d) use of different depth in the source zones. The map was compiled under the review of an international board and will serve as inpu

Sodium Ascorbate induces apoptosis in neuroblastoma cell lines by interfering with iron uptake-2

<p><b>Copyright information:</b></p><p>Taken from "Sodium Ascorbate induces apoptosis in neuroblastoma cell lines by interfering with iron uptake"</p><p>http://www.molecular-cancer.com/content/6/1/55</p><p>Molecular Cancer 2007;6():55-55.</p><p>Published online 30 Aug 2007</p><p>PMCID:PMC2000471.</p><p></p> for 24 hours and iron levels were measured in cell lysates. After terminating the incubation, cells were collected by scraping and washed three times with PBS and then lysed in specific buffer. Iron levels were analyzed with a Cobas Integra 800 system as described under "Material and Method". Values indicated are the mean ± S.D. of three separate experiments

Membrane expression of TfR (CD71) by neuroblastoma cell lines and its modulation by sodium ascorbate

<p><b>Copyright information:</b></p><p>Taken from "Sodium Ascorbate induces apoptosis in neuroblastoma cell lines by interfering with iron uptake"</p><p>http://www.molecular-cancer.com/content/6/1/55</p><p>Molecular Cancer 2007;6():55-55.</p><p>Published online 30 Aug 2007</p><p>PMCID:PMC2000471.</p><p></p> Cells were seeded in six well plates and treated for 6 and 24 hours with increasing concentrations of sodium ascorbate. For each bar group, the concentration was: 0 (control), 0.5 mM, 1 mM, 2 mM and 3 mM. Cells were than washed and incubated with a FITC-coniugated mouse monoclonal antibody specific to human CD71 and analyzed by flow cytometry. The data are the mean ± S.D. from three independent experiments, each in triplicate

Sodium Ascorbate induces apoptosis in neuroblastoma cell lines by interfering with iron uptake-4

<p><b>Copyright information:</b></p><p>Taken from "Sodium Ascorbate induces apoptosis in neuroblastoma cell lines by interfering with iron uptake"</p><p>http://www.molecular-cancer.com/content/6/1/55</p><p>Molecular Cancer 2007;6():55-55.</p><p>Published online 30 Aug 2007</p><p>PMCID:PMC2000471.</p><p></p>of sodium ascorbate (in the presence or absence of FAC 70 μg/ml). After 16 hours, cells detached in the medium were collected by centrifugation, resuspended and incubated with AnnexinV-FITC. Apoptosis was quantified as increased green fluorescence by flow cytometry. The data are the mean ± S.D. from four independent experiments. Statistical analysis was done by Student's test (*, p < 0.005)

Representative example of cytofluorimetric analysis showing the effect of vitamin C alone or in combination with FAC, on the mitochondrial membrane potential of SH-SY5Y (panel A) and HTLA-230 (panel B) stained with JC-1 probe

<p><b>Copyright information:</b></p><p>Taken from "Sodium Ascorbate induces apoptosis in neuroblastoma cell lines by interfering with iron uptake"</p><p>Molecular Cancer 2007;6():55-55.</p><p>Published online 30 Aug 2007</p><p>PMCID:PMC2000471.</p><p></p> In abscissa FL-1 (green fluorescence); in ordinate FL-2 (red fluorescence). Numbers represent the percentage of non-apoptotic red fluorescent cells (R1, R3) and that of apoptotic green fluorescent cells (R2, R4). Sodium ascorbate induces a marked increase in apoptosis which is fully prevented by treatment with FAC. SH-SY5Y and HTLA-230 were incubate in complete medium in the absence (A1, B1) or in presence of 1 mM sodium ascorbate (A2, B2) and 2 mM sodium ascorbate (A4, B4) for 16 hours. Cells were pretreated (A3, A5, B3, B5) with 70 μg/ml of FAC for 3 hours. Comparable results were obtained in three independent experiments