Center for Sickle Cell Disease

Paris, France

Center for Sickle Cell Disease

Paris, France
Time filter
Source Type

Kumari N.,Howard University | Kumari N.,Center for Sickle Cell Disease | Kulkarni A.A.,Howard University | Lin X.,Center for Sickle Cell Disease | And 6 more authors.
Drug Design, Development and Therapy | Year: 2015

Despite the remarkable success of combination antiretroviral therapy at curtailing HIV progression, emergence of drug-resistant viruses, chronic low-grade inflammation, and adverse effects of combination antiretroviral therapy treatments, including metabolic disorders collectively present the impetus for development of newer and safer antiretroviral drugs. Curcumin, a phytochemical compound, was previously reported to have some in vitro anti-HIV and anti-inflammatory activities, but poor bioavailability has limited its clinical utility. To circumvent the bioavailability problem, we derivatized curcumin to sustain retro-aldol decomposition at physiological pH. The lead compound derived, curcumin A, showed increased stability, especially in murine serum where it was stable for up to 25 hours, as compared to curcumin that only had a half-life of 10 hours. Both curcumin and curcumin A showed similar inhibition of one round of HIV-1 infection in cultured lymphoblastoid (also called CEM) T cells (IC50=0.7 μM). But in primary peripheral blood mononuclear cells, curcumin A inhibited HIV-1 more potently (IC50=2 μM) compared to curcumin (IC50=12 μM). Analysis of specific steps of HIV-1 replication showed that curcumin A inhibited HIV-1 reverse transcription, but had no effect on HIV-1 long terminal repeat basal or Tat-induced transcription, or NF-κB-driven transcription at low concentrations that affected reverse transcription. Finally, we showed curcumin A induced expression of HO-1 and decreased cell cycle progression of T cells. Our findings thus indicate that altering the core structure of curcumin could yield more stable compounds with potent antiretroviral and anti-inflammatory activities. ©2015, Kumari et al.

Maier-Redelsperger M.,Service dHematologie Biologique | Maier-Redelsperger M.,Center for Sickle Cell Disease | Maier-Redelsperger M.,University Pierre and Marie Curie | Maier-Redelsperger M.,French Institute of Health and Medical Research | And 14 more authors.
Blood Cells, Molecules, and Diseases | Year: 2010

To perform a precise evaluation of the hemolytic status of patients with sickle cell anemia (SCA), advanced red blood cell parameters provided by the last generation analyzers were investigated in a series of SCA patients. The search for precise markers of hemolysis was performed to identify if patients so exposed develop organic complications related to a postulated hemolysis-linked endothelial dysfunction. Red blood cell survival was evaluated by the ratio between mature red blood cell (RBC) and reticulocyte (RET) hemoglobin (RBC-Hb/RET-Hb). In comparison with serum lactate dehydrogenase (LDH) and total bilirubin, the log (RBC-Hb/RET-Hb) was identified as the most discriminant hematological parameter to evaluate hemolysis. Furthermore, by combining this parameter with LDH, we defined a composite variable, which we called CVar, that is highly correlated with albuminuria and might constitute a powerful new marker of risk for this complication. © 2010 Elsevier Inc.

Haymann J.-P.,University Pierre and Marie Curie | Haymann J.-P.,Center for Sickle Cell Disease | Stankovic K.,Center for Sickle Cell Disease | Levy P.,French Institute of Health and Medical Research | And 9 more authors.
Clinical Journal of the American Society of Nephrology | Year: 2010

Background and objectives: Sickle cell anemia-associated nephropathy is a growing matter of concern because renal failure affects most aging sickle cell anemia patients. Glomerular damage is a common feature revealed by a microalbuminuria or a macroalbuminuria. Although glomerular hyperfiltration has been described for decades in this population, its prevalence in young adults is unknown. Design, setting, participants, & measurements: To address this issue, as well as the clinical and biologic correlates of hyperfiltration, a single-center, cross-sectional study of 280 homozygous ss disease patients was performed. Results: The prevalence of hyperfiltration assessed by Modification of Diet in Renal Disease estimated GFR was 51%. Among patients with hyperfiltration, 49% had hyperfiltration alone, whereas 36% and 15% had an associated microalbuminuria or macroalbuminuria, respectively. Estimated GFR sensitivity and specificity for hyperfiltration were 94% and 63%, respectively, in a selected subgroup of 48 patients (measured GFR was assessed by urinary 51Cr EDTA clearance). In patients with no albuminuria, hyperfiltration status was significantly associated with a young age (years), the absence of alpha thalassemia, a lower hemoglobin level (g/dl), and a lower fetal hemoglobin. The role of chronic hemolysis was further strengthened by multivariate analysis showing a correlation between estimated GFR and a low plasma fetal hemoglobin level, a young age, and a high reticulocyte count (r2 = 0.54). Conclusions: Together, the data suggest that the pathophysiology of hyperfiltration would rather be attributable to the hemolysis-associated vasculopathy rather than a viscosity-vaso-occlusive process. Copyright © 2010 by the American Society of Nephrology.

Jerebtsova M.,Center for Cancer and Immunology | Jerebtsova M.,George Washington University | Kumari N.,Howard University | Obuhkov Y.,Howard University | And 2 more authors.
Molecular and Cellular Proteomics | Year: 2012

Renal glomerular endothelial cells are specialized cells with an important role in physiological filtration and glomerular disease. However, maintenance of human primary endothelial cells requires stimulation with serum and growth factors that often results in modification of the cells properties. Previously, expression of early adenovirus region E4 was shown to help maintaining long-term survival of human endothelial cells in serum free media without addition of growth factors. In the current study, we showed that media conditioned with human epithelial cells stably transfected with Ad E4 region also supported survival of human glomerulus-derived endothelial cells in serum-free media. Mass-spectrometry analysis of the conditioned media identified pigmental epithelium derived factor (PEDF) as a major component of the conditioned media. PEDF expression in 293-E4 cells was validated by RT-PCR, Western blot and ELISA analysis. PEDF expression was detected in mouse glomeruli. Supplementation with recombinant PEDF supported survival of primary endothelial cells and the cells transformed with SV40 large T antigen in serum-free media, and extended the life-span of both cell cultures. PEDF did not inhibit FGF-2 stimulated growth and tubulogenesis of endothelial cells. Thus we demonstrated that adenoviral E4 region stimulated expression and secretion of PEDF by human renal epithelial cells that acted as a survival factor for glomerulusderived endothelial cells. © 2012 by The American Society for Biochemistry and Molecular Biology, Inc.

Loading Center for Sickle Cell Disease collaborators
Loading Center for Sickle Cell Disease collaborators