Efekti IL-17 na funkcionalnu aktivnost ćelija periferne krvi

Interleukin-17 (IL-17) is a proinflammatory cytokine produced mainly by activated CD4+ and CD8+ T cells, while its specific receptor is ubiquitously distributed. The inflammatory capacity of IL-17 is based on its ability to stimulate a wide range of stromal cells to produce and release a number of proinflammatory mediators, some with a known impact on hematopoiesis particularly granulopoiesis. Recent data indicate a role for IL-17 in the pathogenesis of several inflammatory diseases, transplant rejection and tumor growth. The purpose of this study was to determine functional responses including the respiratory burst, nitric oxide (NO) production, adhesiveness and metabolical activity/viability of human peripheral blood leukocytes (total white blood cells, mononuclear cells and granulocytes) from healthy donors in the presence of recombinant human (rh)IL-17. The obtained results showed that rhIL-17 did not induce significant changes in the respiratory burst, NO production, and metabolical activity of each peripheral blood cell fraction the tested, while a slight increase in phorbol-12-myristate-13-acetate (PMA) stimulated adhesiveness of granulocytes and mononuclear cells was noted. The absence of significant changes in tested functional activities of various peripheral blood cells suggests that IL-17 does not express its proinflammatory ability in steady-state, since the requirement for its action really does not exist.Interleukin 17 (IL-17) je proinflamatorni citokin koga produkuju aktivirane CD4+ i CD8+ T ćelije, dok je njegov receptor ubikvitarno distribuiran. Inflamatorni kapacitet IL-17 se zasniva na njegovoj sposobnosti da stimuliše širok spektar stromalnih ćelija da produkuju i oslobađaju različite proinflamatorne medijatore, među kojima neki imaju efekte na hematopoezu posebno granulopoezu. Dosadašnji podaci ukazuju na ulogu IL-17 u patogenezi različitih inflamatornih bolesti, odbacivanju transplanta i razvoju tumora. Cilj ovog rada je bio da se odrede funkcionalni odgovori, uključujući respiratorni prasak, produkciju azot monoksida (NO), adhezivnost i metaboličku aktivnost/vijabilnost različitih ćelija periferne krvi (ukupnih leukocita, mononuklearnih ćelija i granulocita) zdravih donora, u prisustvu IL-17. Dobijeni rezultati su ukazali da IL-17 ne dovodi do značajnih promena respiratornog praska, produkcije NO i metaboličke aktivnosti ćelija periferne krvi, ali da uzrokuje blago povećanje forbol-12-miristat-13-acetat (PMA) stimulisane adhezivnosti granulocita i mononuklearnih ćelija. Odsustvo značajnih promena u ispitivanim funkcionalnim aktivnostima različitih ćelija periferne krvi, ukazuje da IL-17 ne eksprimira proinflamatorno dejstvo kod zdravih osoba, jer najverovatnije i ne postoji potreba za njegovim delovanjem

Additives in Children’s Nutrition—A Review of Current Events

Additives are defined as substances added to food with the aim of preserving and improving safety, freshness, taste, texture, or appearance. While indirect additives can be found in traces in food and come from materials used for packaging, storage, and technological processing of food, direct additives are added to food with a special purpose (canning). The use of additives is justified if it is in accordance with legal regulations and does not pose a health or danger to consumers in the prescribed concentration. However, due to the specificity of the child’s metabolic system, there is a greater risk that the negative effects of the additive will manifest. Considering the importance of the potential negative impact of additives on children’s health and the increased interest in the control and monitoring of additives in food for children, we have reviewed the latest available literature available through PubMed, Scopus, and Google Scholar. Expert data were taken from publicly available documents published from January 2010 to April 2022 by internationally recognized professional organizations. It was found that the most frequently present additives in the food consumed by children are bisphenols, phthalates, perfluoroalkyl chemicals, perchlorates, pesticides, nitrates and nitrites, artificial food colors, monosodium glutamate, and aspartame. Increasing literacy about the presence and potential risk through continuous education of parents and young people as well as active monitoring of newly registered additives and harmonization of existing legal regulations by competent authorities can significantly prevent the unwanted effects of additives on children’s health

Ispitivanje oksidativnog stresa i parametara periferne krvi krava uzgajanih na području izloženom dejstvu municije sa osiromašenim uranijumom (ou)

The paper presents results of the study on depleted uranium (DU) health effects on cows bred in areas exposed to DU ammunition, during NATO bombing of Serbia and Montenegro in 1999. The samples of animal blood, soils and feed were collected randomly in the region of Bujanovac, in 2003. Complete blood cells count was performed according to standard laboratory procedures. Concentration of red blood cells malondialdehyde (RBC MDA) and erythrocyte superoxid dismutase (SOD) activity were determined spectrophotometrically. The functional activity of leukocytes was investigated by NBT reduction and adhesion test. Activity of the radionuclides was determined by standard gamma spectrometry. The obtained results of complete red blood cells count indicate normocytic normochromic anaemia. Considerably increased RBC MDA concentration suggests a violent oxidative stress in cows bred in the exposed area although the activity of their RBC antioxidant enzyme SOD was in the range of values obtained in the control group. The total number of leukocytes and the differential leukocyte counts were within the physiological range. NBT reduction test revealed the absence of leukocyte oxidative burst, which pointed to the absence of inflammation. A significant decrease of granulocyte adhesiveness, pointed at partial impairment of granulocyte functional activity. The activity of 238U/235U in soils and feed was below the minimal detectable concentration (10-3 Bq/kg), while the content of natural (226Ra and 232Th) and anthropogenic 137Cs) radionuclides in soils were within the average values for the region, except for low levels of 40K - indicating soils impoverishment in potassium.U radu su izneti rezultati istraživanja mogućih efekata osiromašenog uranijuma (OU) na zdravlje krava uzgajanih u području dejstava tokom NATO bombardovanja Srbije i Crne Gore, 1999 godine. Uzorci krvi, zemljišta i hraniva sakupljeni su u regionu Bujanovca 2003 godine. Životinjama je urađena kompletna krvna slika i ispitana je funkcionalna aktivnost njihovih leukocita. U eritrocitima istih krava je određena koncentracija pokazatelja oksidativnog stresa - malondialdehida (RBC MDA) i aktivnost enzima antioksidativne odbrane - eritrocitne superoksid dismutaze (SOD). Standardnom metodom spektrometrije gama zračenja određena je aktivnost radionuklida u zemljištu i hrani. Dobijeni rezultati ukazuju na postojanje normocitno normohromne anemije kod krava sa područja izloženih dejstvu OU. Značajno povećanje koncentracije RBC MDA, ukazuje da su životinje bile izložene jakom oksidativnom stresu, iako je aktivnost eritrocitnog antioksidnog enzima SOD bila u opsegu vrednosti dobijenih kod kontrolne grupe životinja. Ukupan broj leukocita i leukocitarna formula su bili fiziološkim granicama. Odsustvo leukocitnog oksidativnog praska, potvrđeno NBT redukcionim testom, isključuje postojanje inflamatornog procesa, dok značajno smanjenje adhezivnosti leukocita, ustanovljeno NBT adhezionim testom, upućuje na smanjenu funkcionalnu sposobnost leukocita krava koje potiču sa prostora izloženog uticaju OU. Aktivnost 238u/235U u zemljištu i hranivima je bila ispod minimalne koncentracije (10~3Bq/kg) koja se može izmeriti, dok je sadržaj prirodnih radionuklida 226Ra i 232Th, kao i antropogenog 137Cs u zemljištu bio u opsegu srednjih vrednosti za region. Znatno niže vrednosti prirodnog 40K ukazuju na zemljište siromašno kalijumom. Dobijeni rezultati nesumnjivo ukazuju da su ispitivane krave bile izložene snažnom oksidativnom stresu, ali zbog nedostatka pouzdanih podataka o distribuciji OU u životnoj sredini, ne možemo sa sigurnošću tvrditi da su ustanovljeni efekti posledica delovanja municije sa osiromašenim uranijumom

Interleukine-17-induced inhibitory effect on late stage murine erythroid bone marrow progenitors

Recent studies have shown that the T cell-derived cytokine, interleukin-17 (IL-17), stimulates hematopoiesis, specifically granulopoiesis inducing expansion of committed and immature progenitors in bone marrow. Our previous results pointed to its role in erythropoiesis too, demonstrating significant stimulation of BFU-E and suppression of CFU-E growth in the bone marrow from normal mice. As different sensitivities of erythroid and myeloid progenitor cells to nitric oxide (NO) were found, we considered the possibility that the observed effects of IL-17 were mediated by NO. The effects of recombinant mouse IL-17, NO donor (sodium nitroprusside - SNP) and two NO synthases inhibitors (L-NAME and aminoguanidine) on erythroid progenitor cells growth, as well as the ability of IL-17 to induce nitric oxide production in murine bone marrow cells, were examined. In addition, we tested whether the inhibition of CFU-E colony formation by IL-17 could be corrected by erythropoietin (Epo), the principal regulator of erythropoiesis. We demonstrated that IL-17 can stimulate low level production of NO in murine bone marrow cells. Exogenously added NO inhibited CFU-E colony formation, whereas both L-NAME and aminoguanidine reversed the CFU-E suppression by IL-17 in a dose-dependent manner. The inhibition of CFU-E by IL-17 was also corrected by exposure to higher levels of Epo. The data obtained demonstrated that at least some of the IL-17 effects in bone marrow related to the inhibition of CFU-E, were mediated by NO generation. The fact that Epo also overcomes the inhibitory effect of IL-17 on CFU-E suggests the need for further research on their mutual relationship and co-signalling

Mehanizmi prenosa signala u toku stimulacije matičnih ćelija hematopoeze

Different biological functions of hematopoietic cells are regulated by signals cells receive from their environment that may come from interactions with other cells or from soluble growth factors and cytokines. Although the effects of hematopoietic regulators are well described, the exact intracellular signaling cascades leading to various cellular responses are not fully elucidated. All hematopoietic growth factors and cytokines seem able to activate all the major signal transduction pathways simultaneously, and it appears that the same network of signaling proteins may coordinate numerous cellular functions. However, the differences that lead to the unique biological events of the particular cytokine, as well as the differences that determine lineage-specific blood cell differentiation are only gradually being uncovered. With the help of specific inhibitors of known signal transduction pathways, we have examined the contribution of particular signaling molecules of Jak/Stat, MAP kinase and PI-3 kinase pathways, as well as the activation of nuclear factor kappaB (NFkB) transcription factor on the proliferation and differentiation of murine bone marrow granulocyte-macrophage (CFU- GM) and erythroid (BFU-E and CFU-E) progenitors. Preliminary results demonstrated that the effects of the inhibitors on the hematopoietic colony formation were lineage-dependent, as well as dependent on erythroid progenitors' stage of differentiation. The obtained differences suggest that different signal transduction intermediates regulate erythroid and myeloid progenitor cell proliferation and differentiation. Differences in the susceptibility of the progenitor cells to the inhibitors used were also observed. The data is consistent with other evidences indicating that different threshold levels are one of the mechanisms by which the signaling specificity may be achieved.Mnogobrojne funkcije hematopoetskih ćelija u toku procesa hematopoeze, regulisane su brojnim signalima koje ćelije primaju iz svoje okoline i to kako od drugih ćelija tako i od brojnih regulatornih molekula. Iako su biološki efekti regulatora hematopoeze uglavnom dobro opisani, putevi prenošenja signala unutar ćelija na koje deluju nisu još uvek u potpunosti razjašnjeni. Savremena istraživanja ukazuju da gotovo svi poznati hematopoetski regulatori mogu da aktiviraju gotovo sve bitne puteve prenošenja signala unutar ćelija, što sve upućuje da ista mreža signalnih komponenti može da koordinira brojne ćelijske funkcije. Međutim, razlike u transdukciji signala koje dovode do jedinstvenog biološkog dejstva svakog citokina, kao i razlike u prenosu signala kojom se određuje lozno-zavisna diferencijacija krvnih ćelija nisu još poznati. Naša istraživanja započela su određivanjem učešća pojedinih komponenti JAK/STAT puta signalizacije, MAP kinazne kaskade i PI-3 kinaznog puta, kao i aktivacije transkripcionog faktora NFKB, u proliferaciji i diferentovanju opredeljenih matičnih ćelija granulocitno-monocitne (CFU-GM) i eritrocitne (BFU- E i CFU-E) loze kostne srži normalnih miševa. Početni rezultati ovih ispitivanja su ukazali na postojanje kako lozno-zavisnih razlika u odgovoru matičnih ćelija hematopoeze na pojedine inhibitore, tako i na zavisnost odgovora od stepena zrelosti matičnih ćelija u okviru iste loze. Dobijene razlike upućuju da su različiti učesnici signalnih puteva uključeni u regulaciju proliferacije i diferencijacije eritrocitnih i granulocitno-monocitnih progenitora. Ovo je jedan od mogućih načina kojim se možda omogućava selektivna ekspanzija ćelija određenih krvnih loza u zavisnosti od potreba organizma. Takođe, uočene su i razlike u pragu osetljivosti različitih kategorija opredeljenih matičnih ćelija hematopoeze na ispitivane inhibitore signalnih puteva, što ide u prilog podacima da su različiti pragovi osetljivosti jedan od mogućih mehanizama kojim se najverovatnije ostvaruje specifičnost delovanja signalnih puteva

Signaling pathways implicated in hematopoietic progenitor cell proliferation and differentiation

The objective of this study was to investigate the signal transduction pathways associated with the clonal development of myeloid and erythroid progenitor cells. The contribution of particular signaling molecules of protein tyrosine kinases (PTKs), mitogen-activated protein (MAP) kinase, and PI-3 kinase signaling to the growth of murine bone marrow colony forming unit-granulocyte-macrophage (CFU-GM) and erythroid (burst forming unit-erythroid [BFU-E] and colony forming unit-erythroid [CFU-E]) progenitors was examined in studies performed in the presence or absence of specific signal transduction inhibitors. The results clearly pointed to different signal transducing intermediates that are involved in cell proliferation and differentiation depending on the cell lineage, as well as on the progenitors' maturity. Lineage-specific differences were obtained when chemical inhibitors specific for receptor- or nonreceptor-PTKs, as well as for the main groups of distinctly regulated MAPK cascades, were used because all of these compounds suppressed the growth of erythroid progenitors, with no major effects on myeloid progenitors. At the same time, differential involvement of MEK/extracellular signal-regulated kinase (ERK) MAPK transduction pathway was observed in the proliferation and/or differentiation of early, BFU-E, and late, CFU-E, erythroid progenitor cells. The results also demonstrated that phosphatydylinositol (PI)-3 kinase and nuclear factor kappaB (NF-kappa B) transcriptional factor were required for maintenance of both myeloid and erythroid progenitor cell function. Overall, the data obtained indicated that committed hematopoietic progenitors express a certain level of constitutive signaling activity that participates in the regulation of normal steady-state hematopoiesis and point to the importance of evaluating the impact of signal transduction inhibitors on normal bone marrow when used as potential therapeutic agents

The effect of interieukin-17 on hematopoietic cells and cytokine release in mouse spleen

To evaluate whether the response of hematopoietic cells to interleukin-17 (IL-17) depends on the tissue microenvironment in which hematopoiesis occurs, the influence of recombinant mouse IL-17 on spleen hematopoietic cells and cytokine release was assessed in normal mice in vitro and in vivo. In vitro, IL-17 did not significantly affect the growth of granulocyte-macrophage (CFU-GM) and erythroid (BFU-E and CFU-E) derived colonies. A single injection of IL-17 in vivo exhibited stimulatory effects on hematopoietic cells from both granulocytic and erythroid lineages. The increased number of metamyelocytes 48 h after treatment imply to the IL-17-induced stimulation of granulopoiesis. The number of BFU-E was increased at 24 h, while the number of CFU-E increased 6 h and 24 h after treatment. Since the same treatment in the bone marrow decreased the number of CFU-E, it may be concluded that the local microenvironment plays an important role in IL-17-mediated effects on CFU-E. IL-17 increased the release of IL-6 both in vitro and in vivo, but showed tendency to suppress the constitutive secretion of IL-10 by spleen cells. Our results suggest the complexity of target cell response and interplay of secondary induced cytokines by IL-17 in different hematopoietic organs

Ispitivanje oksidativnog stresa kod ovaca u oblastima izloženim dejstvu osiromašenog uranijuma

The paper presents the preliminary results of the study on environmental and health effects due to the use of depleted uranium (DU) ammunition during NATO bombing of Serbia and Montenegro in 1999. The blood samples of sheep were collected randomly in the region of Bujanovac, in 2003. To assess the possible effects of DU on animal health, some of the relevant biochemical and hematological blood parameters were analyzed: concentration of RBC MDA (red blood cells malondialdehide), erythrocytes superoxid dismutase (SOD) activity, hemoglobin concentration and number of erythrocytes (Er). Functional activity of leukocytes (Le) was performed using NBT reduction and adhesion test. The results are considered in correlation with the data on the content of DU that entered the environment during the bombing. The obtained results on peripheral blood hematological and biochemical parameters indicated that animals were under violent oxidative stress. However, there were not enough data, especially on the content of DU in the environmental samples in the region (soils, vegetation, feed) to enable a conclusive correlation of the blood data with the effects of DU.U radu su prikazani preliminarni rezultati ispitivanja mogućih efekata municije sa osiromašenim uranijumom upotrebljene tokom NATO bombardovanja Srbije i Crne Gore 1999. godine, na zdravlje životinja i životnu sredinu. Uzorci krvi su sakupljani od ovaca, metodom slučajnog izbora, u proleće 2003 godine. U cilju ispitivanja mogućeg dejstva osiromašenog uranijuma na zdravlje životinja, analizirani su neki od relevantnih biohemijskih i hematoloških parametara: koncentracija malondialdehida u eritrocitima, aktivnost eritrocitne superoksid dismutaze, koncentracija hemoglobina, broj eritrocita i dr. Funkcionalna aktivnost leukocita je ispitana testom NBT redukcije i adhezije. Rezultati su razmotreni u korelaciji sa podacima o sadržaju osiromašenog uranijuma koji je dospeo u životnu sredinu tokom bombardovanja. Hematološki i biohemijski parametri periferne krvi ukazuju da su životinje bile izložene jakom oksidativnom stresu. Međutim, nepostojanje pouzdanih podataka o sadržaju DU u području sa koga su ispitivane životinje, ne omogućava ustanovljavanje pouzdane korelacije između dobijenih rezultata i efekata osiromašenog uranijuma koji je dospeo u životnu sredinu

Low-oxygen and high-carbon-dioxide atmosphere improves the conservation of hematopoietic progenitors in hypothermia

BACKGROUND: During short-term storage of hematopoietic cells (HCs) at 4 degrees C a substantial decline in number and in functional capacity of progenitors occurs after 3 days. We hypothesized that physiologic O-2 and CO2 concentrations of hematopoietic tissue microenvironment (approx. 3% O-2 and approx. 6% CO2) could improve cell viability and functionality during storage at 4 degrees C. STUDY DESIGN AND METHODS: Mobilized peripheral blood (PB) CD34+ cells from multiple myeloma or non-Hodgkins lymphoma patients were stored in flasks containing air (approx. 20% O-2 and approx. 0.05% CO2) or 3% O-2/6% CO2 atmosphere, for 3, 5, and 7 days at 4 degrees C. The total number of cells, the number of cells in G0 or G1 phase of cell cycle, and the apoptosis rate were determined. The functional capacity of stored cells was assessed by the capacity of progenitors to form colonies in methylcellulose (colony-forming cells [CFCs]) and of stem cells to repopulate the bone marrow (BM) of immunodeficient mice (SCID-repopulating cell [SRC] assay). RESULTS: The total number of viable cells and cells in G1 phase as well as the number of total CFCs were significantly higher at 3% O-2/6% CO2 than in air at all time points. Cells in G0 phase and SRC were equally preserved in both conditions. CONCLUSION: Atmosphere with low O-2 and high CO2 concentration (3% O-2/6% CO2) in hypothermia (+4 degrees C) during 7 days of storage prevents cell damage and preserves a high number of functional HSCs and progenitors mobilized in PB by granulocyte-colony-stimulating factor

Low O-2 concentrations enhance the positive effect of IL-17 on the maintenance of erythroid progenitors during co-culture of CD34+and mesenchymal stem cells

Co-culture of haematopoietic cells with a stromal cell layer does not mimic the physiological, micro-environmental niche, whose major feature is a low oxygen (O-2) concentration. Thus, in order to study the effects of IL-17 in a context which better approximates the physiological state, we investigated its effects on cell expansion, colony-forming ability, and the phenotypical profile of normal, human blood CD34(+) cells co-cultured for five days with MSC layers at various O-2 concentrations (20%, 12.5% and 3% O-2). We demonstrated that IL-17 enhances CD34(+) and total CFC production during the five days of MSC/CD34(+) co-culture. This effect depends upon the O-2 concentration, reaching its maximum at 3% O-2, and is more pronounced on erythroid progenitors (BFU-E). In addition, the stimulation of IL-6 production by IL-17 in MSC cultures and co-cultures is enhanced by low O-2 concentration. The expression of some differentiation markers (CD34, CD13 and CD41) on haematopoietic cells in co-cultures also depends upon the oxygen concentration. Our results strengthen the concept that physiological levels of O-2 (mistakenly called hypoxia), should be considered as an important environmental factor that significantly influences cytokine activity