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Cadmium levels in cord blood (CdB) of 40 neonates living in the town of Chorzów (Upper Silesia) have been determined. The mean CdB concentration was 0.439 μg/dl (SD=0.185). Smoking before and during pregnancy raised CdB levels in newborns. Mean Cd concentration in the neonates born to smoking mothers was 0.504 versus 0.353 μg/dl in those of woman who did not smoke during pregnancy.
In the human body, stem cells are located in niches, which are extremely complex microenvironments (with specified oxygen conditions and cellular together with extracellular matrix components arranged as a 3D structure). The influence of signals from niches seems to play an important role in maintenance of stem cells pluripotency and in their differentiation. We have been investigating the influence of the different niche components on the proliferation and differentiation of neural stem cells into specific cell types as well as the molecular mechanisms underlying this cell responses. In this study we are investigating the influence of low oxygen tension conditions on proliferation and differentiation of Human Umbilical Cord Blood of Neural Stem Cell (HUCB-NSC). Human Neural Stem Cells (NSC) in their physiological niches are exposed to 2–8% oxygen level. For that purpose, HUCB-NSC, were cultivated in two oxygen tension conditions: 21% and 5% with or without the presence of differentiation factor dBcAMP (N6,2′-O-Dibutyryladenosine 3′,5′-cyclic monophosphate sodium salt). We compared the expression of the markers characteristic for proliferation (Ki67) as well as neuronal and astroglial lineage commitment (MAP2, GFAP, β-tubulin, NF200). The presence of tested markers was revealed on the protein (immunocytochemistry) and gene expression level (Real-Time PCR). Our data show, that the low oxygen tension promote HUCB-NSC differentation into neuronal lineage. We also observed that low concentration of oxygen increases cell proliferation.Sponsored by grant from Polish Ministry of Scientific Research and Higher Education No 5978/B/PO1/2010/38
Lead levels in cord blood (PbB) of 92 neonates living in the town of Chorzów (Upper Silesia) have been determined. The mean PbB concentration was 5.29mg/dl (SD= 2.24) in the all investigated groups.The mean Pb-CB was higher in preterm babies (x= 6.87mg/dl, SD=1.67 ), especially in boys. Pb-CB concentrations were higher in the neonates born to mothers aged more than 30 years, smoking before and during pregnancy, having bad living conditions, living close to gasoline station.
The signal transducers and activators of transcription - STAT5A and STAT5B - are responsible for the control of proliferation, differentiation and apoptosis, via their effect on gene expression. They are activated by the binding of many cytokines, growth factors and hormones to their receptors on the cell surface. Many of these cytokines regulate hematopoietic cell development; therefore, STAT5 proteins are suggested to play an important role in hematopoiesis. There are numerous contradictory reports available in the literature on the role of STAT5 in normal hematopoietic cell development; hence, the question of the real function of STAT5 proteins clearly requires further studies. The aim of our study was to evaluate the role of STAT5 in normal hematopoiesis using oligodeoxynucleotide (ODN) strategy against STAT5 mRNA. We employed the RT-PCR method to study STAT5 mRNA expression in cells after their incubation with ODNs. We analyzed the effect of blocking STAT5 proteins on the viability and clonogenecity of the CFU-GM (Colony Forming Unit of Granulocyte-Macrophages) and the BFU-E (Burst Forming Unit of Erythrocytes) obtained from human cord blood (CB). The clonogenic growth of the cells was assessed in methylcellulose cultures according to the type of oligodeoxynucleotides. We also attempted to estimate the level of apoptosis induced in cord blood mononuclear and CD34+ cells by employing different assays: i) Annexin V staining using flow cytometry (FACSCalibur); ii) terminal deoxynucleotidyltransferase dUTP nick end labeling (TUNEL); iii) analysis of Bax and Bcl-XL gene expression by RT-PCR. Perturbation of STAT5 expression with antisense oligodeoxynucleotides had no impact on the viability, clonogenecity and apoptosis of CB hematopoietic cells. Our results showed that STAT5 proteins do not play a significant role in the regulation of proliferation of normal hematopoietic cells derived from cord blood.
The oxygen tension is an important factor modulating cell fate and developmental decisions. There are evidences that HIFs (Hypoxia Inducible Factors) family is implicated in the regulation of pluripotency and differentiation genes. The goal of this study is to compare the influence of close to physiological oxygen conditions (5%) to atmospheric oxygen tension on differentiation process and pluripotent activity in HUCB-NSC. The expression of Hypoxia Inducible Factors, stemness and neural differentiation markers in NSC, cultured under 5% and 21% oxygen were checked on the transcriptional and translational level. We were looking at the interaction between HIFs (HIF1 alpha, HIF 2 alpha) and activity of neural differentiations genes (MAP2, GFAP, β-tubulin) as well as expression of pluripotency genes (Oct4, Sox2, Rex1 and Nanog). In order to demonstrate the impact of increased HIF1α and/ or HIF2α level on cell differentiation we used DMOG (Sigma) which is of prolyl-4-hydroksylase inhibitor to increase HIF alpha levels. Our data show, that low oxygen conditions promote proliferation of HUCBNSC at early stage of development and can activate Oct4 and Nanog genes in HUCB-NSC. The time of cultivation of the cells in low oxygen conditions and the developmental stage of the cells are the important factors for the induction of the expression of “pluripotency” genes.Hypoxia Inducible Factors HIF 1α and HIF 2α, but not HIF3α are expressed in HUCB-NSC at all stages of development. During neuronal differentiation of HUCB-NSC by using dBcAMP, 5% oxygen level act synergistically, promoting further differentiation (enhanced MAP2 expression). Application of prolyl hydroxylase inhibitor – DMOG resulted in increased expression of HIF1α but not HIF2α and increased the expression of MAP2 (only in 21% oxygen conditions) referring to variants without DMOG. Sponsored by grant from Polish Ministry of Scientific Research and Higher Education No N N302 597838 and by NSC grant No 2011/01/B/NZ3/05401
Human umbilical cord blood is frequently used as a source of transplantable hematopoietic cells and more recently as a target of gene therapy - a new approach for treatment of various disorders. The aim of our study was optimisation of the transfection conditions of cord blood-derived CD34+ hematopoietic cells. Mononuclear cells fraction was isolated from cord blood samples by density gradient centrifugation. Subsequently, CD34+ hematopoietic cells were separated on immuno- magnetic MiniMACS columns. Pure population of CD34+ cells was incubated in a se­rum free medium supplemented with thrombopoietin, stem cell factor and Flt-3 ligand for 48 h and then transfected with plasmid DNA carrying the enhanced version of green fluorescent protein (EGFP) as a reporter gene. We studied the influence of vari­ous pulse settings and DNA concentrations on the transfection efficiency, measured by flow cytometry as the fluorescence of target cells due to the expression of EGFP. The optimal settings were as follows: 4 mm cuvette, 1600 iF, 550 V/cm, and 10 ug of DNA per 500 ul. With these settings we obtained a high transfection frequency (41.2%) without a marked decrease of cell viability. An increase of the pulse capaci­tance and/or of DNA concentration resulted in a greater electroporation efficiency, but also in a decrease of cell viability. In conclusion, the results described here allow one to recommend electroporation as an efficient method of gene delivery into CD34+ hematopoietic cells derived from human umbilical cord blood.
We krwi pępowinowej i łożysku kobiet mieszkanek okolic Cieszyna i Katowic oznaczono zawartość 7 metali ciężkich. Do oceny źródeł zanieczyszczenia organizmu metalami zastosowano analizę skupień i analizę czynników głównych. Na zawartość metali w łożyskach kobiet mieszkających w Katowicach wpływał głównie przemysł hutniczy, metalurgiczny, a także spalanie węgla i odpadów. Obecność metali we krwi pępowinowej i łożyskach kobiet mieszkających w okolicy Cieszyna była związana z emisją daleko- zasięgową znad Czech.
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