18 research outputs found
Chlorella Vulgaris Treatment Ameliorates The Suppressive Effects Of Single And Repeated Stressors On Hematopoiesis.
The reports regarding the mutual influence between the central nervous system and the immune system constitute a vast and somewhat controversial body of literature. Stress is known to disturb homeostasis, impairing immunological functions. In this study, we investigated the hematopoietic response of Chlorella vulgaris (CV)-treated mice exposed to single (SST) and repeated stress (RST). We observed a reduction in the numbers of hematopoietic progenitors (HP) in the bone marrow and long-term bone marrow cultures (LTBMC) using flow cytometry and a coinciding decrease in the number of granulocyte-macrophage colonies (CFU-GM) after treatment with both stressors, but SST caused a more profound suppression. We observed a proportional increase in the colony-stimulating activity (CSA) of the serum of animals subjected to SST or RST. In the bone marrow, SST and RST induced a decrease in both mature myeloid and lymphoid populations but did not affect pluripotent hematopoietic progenitors (Lin(-)Sca-1(+)c-kit(+), LSK), and again, a more profound suppression was observed after SST. We further quantified the levels of interleukin-1α (IL-1α) and interleukin-6 (IL-6) and the number of myeloid cells in LTBMC. Both SST and RST reduced the levels of these cytokines to similar degrees. The myeloid population was also reduced in LTBMC, and SST induced a more intense suppression. Importantly, CV treatment prevented the changes produced by SST and RST in all of the parameters evaluated. Together, our results suggest that CV treatment is an effective tool for the prophylaxis of myelosuppression caused by single or repeated stressors.2939-5
Hematopoietic stem cell expansion caused by a synthetic fragment of leptin
Leptin is a cytokine that regulates food intake, energy expenditure and hematopoiesis. Based on the tridimensional structure of the human leptin molecule, six fragments have been synthesized, (Ac-Lep(23-47)-NH2, [LEP1]; Ac-Lep(48-71)-NH2, [LEP2]; Ac-Lep(72-88)-NH2, [LEP3]; Ac-Lep(92-115)-NH2, [LEP4], Ac-[Ser(117)]-Lep(116-140)-NH2, [LEP5] and Ac-Lep(141-164)-NH2, [LEP6]), and their effects on hematopoiesis were evaluated. the mice were treated with 1 mg/kg LEP5 for 3 days. the mature and primitive hematopoietic populations were quantified. We observed that the mature populations from the bone marrow and spleen were not affected by LEP5. However, the peptide caused at least a two-fold increase in the number of hematopoietic stem cells, the most primitive population of the bone marrow. Additionally, the number of granulocyte/macrophage colony-forming units produced by bone marrow cells in methylcellulose also increased by 40% after treatment with LEP5, and the leptin receptor was activated. These results show that the leptin fragment LEP5 is a positive modulator of the in vivo expansion of hematopoietic stem cells. (C) 2013 Elsevier Inc. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de NÃvel Superior (CAPES)Universidade Federal de São Paulo, Dept Bioquim, BR-04044020 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biofis, BR-04044020 São Paulo, BrazilUniv Fed ABC, Ctr Ciencias Nat & Humanas, BR-09210170 Santo Andre, SP, BrazilUniversidade Federal de São Paulo, Dept Bioquim, BR-04044020 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biofis, BR-04044020 São Paulo, BrazilFAPESP: 2009/54869-2Web of Scienc
alpha-Tocopherol induces hematopoietic stem/progenitor cell expansion and ERK1/2-mediated differentiation
Tocopherols promote or inhibit growth in different cell types. in the hematopoietic system, the radioprotective property of tocopherols is thought to act through the expansion of primitive hematopoietic cells. However, the mechanisms activated by tocopherols and which HPs are affected remain poorly understood. To better address these questions, mice were treated with alpha-tocopherol, and its effects were investigated in the BM microenvironment. alpha-Tocopherol induced increased proliferation in HSC/HP cells, leading to BM hyperplasia. in addition, differentiation to the granulocytic/monocytic lineage was enhanced by alpha-tocopherol treatment. alpha-Tocopherol treatment resulted in decreased basal phosphorylation of ERK1/2, PKC, and STAT-5 in HSC/HP cells. in contrast, alpha-tocopherol enhanced ERK1/2 activation in response to IL-3 stimulation in HSC/HP cells without altering the expression of IL-3Rs. Moreover, alpha-tocopherol-induced differentiation and ERK1/2 activation were abolished in mice pretreated with a MEK inhibitor (PD98059); however, pretreatment with PD98059 did not reduce the alpha-tocopherol-mediated increase in HSC/HP cells but instead, further enhanced their proliferation. Therefore, alpha-tocopherol induces expansion of HSC/HP cells by a nonidentified intracellular pathway and granulocytic/monocytic differentiation through ERK1/2 activation. J. Leukoc. Biol. 90: 1111-1117; 2011.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de NÃvel Superior (CAPES)Universidade Federal de São Paulo, Dept Bioquim, BR-04044020 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biofis, BR-04044020 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Oncol Clin & Expt, BR-04044020 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Psicobiol, BR-04044020 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Bioquim, BR-04044020 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biofis, BR-04044020 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Oncol Clin & Expt, BR-04044020 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Psicobiol, BR-04044020 São Paulo, BrazilWeb of Scienc
Autophagy inhibited Ehrlich ascitic tumor cells apoptosis induced by the nitrostyrene derivative compounds: Relationship with cytosolic calcium mobilization
Apoptosis induction is often associated with increased autophagy, indicating interplay between these two important cellular events in cell death and survival. in this study, the programmed cell death and autophagy induced by two nitrostyrene derivative compounds (NTS1 and NTS2) was studied using the tumorigenic Ehrlich ascitic tumor (EAT) cells. EAT cells were highly sensitive to NTS1 and NTS2 cytotoxicity in a dose-dependent manner. NTS1 and NTS2 IC50 was less than 15.0 mu M post 12 h incubation. Apoptosis was primarily induced by both compounds, as demonstrated by an increase in Annexin-V positive cells, concurrently with cytochrome c release from mitochondria to cytosol and caspase-3 activation. Although cytosolic Ca2+ mobilization is involved in autophagy as well as apoptosis in response to cellular stress in many cancer cell types, from the two nitrostyrene derivative compounds studied, mainly NTS1 mobilized this ion and disparate autophagy in EAT cells. These results suggest that EAT induced cell death by NTS1 and NTS2 involved a Ca2+-dependent and a Ca2+-independent pathways, respectively. in accordance with these results, the treatment of EAT cells with 3 methyladenine (3-MA), an autophagy inhibitor; significantly increased the number of apoptotic cells after NTS1 treatment, suggesting that pharmacological modulation of autophagy augments the NTS1 efficacy. Thus, we denote the importance of studies involving autophagy and apoptosis during pre-clinical studies of new drugs with anticancer properties. (C) 2011 Elsevier B. V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de NÃvel Superior (CAPES)Universidade Federal de São Paulo UNIFESP, Escola Paulista Med, Dept Farmacol, São Paulo, BrazilUniv Estadual Campinas, UNICAMP, Dept Farmacol, FCM, Campinas, SP, BrazilUniversidade Federal de São Paulo UNIFESP, Escola Paulista Med, Dept Biofis, São Paulo, BrazilUniversidade Federal de São Paulo UNIFESP, Escola Paulista Med, Dept Farmacol, São Paulo, BrazilUniversidade Federal de São Paulo UNIFESP, Escola Paulista Med, Dept Biofis, São Paulo, BrazilWeb of Scienc
Biphosphinic palladacycle complex mediates lysosomal-membrane permeabilization and cell death in K562 leukaemia cells
The cell death mechanism of cytotoxicity induced by the Biphosphinic Palladacycle Complex (BPC) was studied using a K562 leukaemia cell line. the IC50 values obtained for K562 cells post-72 h of BPC were less than 5.0 mu M by using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) and trypan blue assays. Using the Acridine Orange vital staining combining fluorescence microscopy it was observed that the complex triggers apoptosis in K562 cells, inducing DNA fragmentation, as analysed through electrophoresis. Lysosomal-membrane permeabilization was also observed in K562 cells post-5 h of BPC, which suggests intralysossomal accumulation by proton-trapping, since its pK(a) value ranged from 5.1 to 6.5. Caspase-3, and -6 activity induced by BPC in K562 cells was prevented by the cathepsin-B inhibitor [N-(L-3-transpropylcarbamoyl-oxirane-2-carbonyl)-L-isoleucyl-L-proline] (CA074). These events occurred in the presence of endogenous bcl-2 and bax expression. Acute toxicological studies demonstrated that BPC produces no lesions for liver and kidney fourteen-days after drug administration (100 mg/kg - i.p.). White and red blood cells of BPC-treated mice presented normal morphological characteristics. Taken together, these data suggest a novel lysosomal pathway for BPC-induced apoptosis, in which lysosomes are the primary target and cathepsin B acts as death mediator. (c) 2006 Elsevier B.V. All rights reserved.UMC, CIIB, BR-08701970 Mogi das Cruzes, SP, BrazilUniv São Paulo, Inst Ciencias Biomed 4, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Bioquim, São Paulo, BrazilUniv Estadual Campinas, Fac Ciencias Med, Dept Farmacol, Campinas, SP, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Bioquim, São Paulo, BrazilWeb of Scienc
Palladacycle (BPC) antitumour activity against resistant and metastatic cell lines: the relationship with cytosolic calcium mobilisation and cathepsin B activity
The search for new compounds that induce p53-independent apoptosis is the focus of many studies in cancer biology because these compounds could be more specific and would overcome chemotherapy resistance. in this study, we evaluated the in vitro antitumour activity of a Biphosphinic Palladacycle Complex (BPC) and extended preclinical studies to an in vivo model. Saos-2 cells, a p53-null human osteosarcoma drug-resistant cell line, were treated with BPC in the presence or absence of a cathepsin B inhibitor and a calcium chelator (CA074 and BAPTA-AM, respectively), and several parameters related to apoptosis were evaluated. Preclinical studies were performed with mice that were intravenously inoculated with murine melanoma Bl6F10-Nex2 cells and treated intraperitoneally (i.p.) with BPC (8 mg/kg/ day) for ten consecutive days, when lung metastatic nodules were counted. in vitro data show that BPC induces cell death in Saos-2 cells mainly by apoptosis, which was accompanied by the effector caspase-3 activation. These events are most likely related to Bax translocation and increased cytosolic calcium mobilisation, mainly from intracellular compartments. Lysosomal Membrane Permeabilisation (LMP) was also observed after 12 h of BPC exposure. Interestingly, BAPTA-AM and CA074 significantly decreased BPC cytotoxicity, suggesting that both calcium and cathepsin B are required for BPC antitumour activity. in vivo studies demonstrated that BPC protects mice against murine metastatic melanoma. in conclusion, BPC complex is an effective anticancer compound against metastatic murine melanoma. This complex is cytotoxic to the drug-resistant osteosarcoma Saos-2 human tumour cells by inducing apoptosis triggered by calcium signalling and a lysosomal-dependent pathway. (C) 2014 Elsevier Masson SAS. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de NÃvel Superior (CAPES)Universidade Federal de São Paulo, UNIFESP, Dept Farmacol, EPM, São Paulo, BrazilUniversidade Federal de São Paulo, UNIFESP, Dept Biofis, EPM, São Paulo, BrazilUniversidade Federal de São Paulo, UNIFESP, Unidade Oncol Expt, EPM, São Paulo, BrazilUniv Bandeirante São Paulo UNIBAN, São Paulo, BrazilUniv Mogi das Cruzes, Ctr Interdisciplinar Invest Bioquim, Mogi Das Cruzes, SP, BrazilUniversidade Federal de São Paulo, UNIFESP, Dept Farmacol, EPM, São Paulo, BrazilUniversidade Federal de São Paulo, UNIFESP, Dept Biofis, EPM, São Paulo, BrazilUniversidade Federal de São Paulo, UNIFESP, Unidade Oncol Expt, EPM, São Paulo, BrazilFAPESP: 10/51647-6Web of Scienc
Autophagy Inhibited Ehrlich Ascitic Tumor Cells Apoptosis Induced By The Nitrostyrene Derivative Compounds: Relationship With Cytosolic Calcium Mobilization.
Apoptosis induction is often associated with increased autophagy, indicating interplay between these two important cellular events in cell death and survival. In this study, the programmed cell death and autophagy induced by two nitrostyrene derivative compounds (NTS1 and NTS2) was studied using the tumorigenic Ehrlich ascitic tumor (EAT) cells. EAT cells were highly sensitive to NTS1 and NTS2 cytotoxicity in a dose-dependent manner. NTS1 and NTS2 IC(50) was less than 15.0μM post 12h incubation. Apoptosis was primarily induced by both compounds, as demonstrated by an increase in Annexin-V positive cells, concurrently with cytochrome c release from mitochondria to cytosol and caspase-3 activation. Although cytosolic Ca(2+) mobilization is involved in autophagy as well as apoptosis in response to cellular stress in many cancer cell types, from the two nitrostyrene derivative compounds studied, mainly NTS1 mobilized this ion and disparate autophagy in EAT cells. These results suggest that EAT induced cell death by NTS1 and NTS2 involved a Ca(2+)-dependent and a Ca(2+)-independent pathways, respectively. In accordance with these results, the treatment of EAT cells with 3 methyladenine (3-MA), an autophagy inhibitor; significantly increased the number of apoptotic cells after NTS1 treatment, suggesting that pharmacological modulation of autophagy augments the NTS1 efficacy. Thus, we denote the importance of studies involving autophagy and apoptosis during pre-clinical studies of new drugs with anticancer properties.6786-1
Chlorella Vulgaris Restores Bone Marrow Cellularity And Cytokine Production In Lead-exposed Mice.
Chlorella vulgaris (CV) was examined for its modulating effects on the reduction induced by lead (Pb) on the numbers of marrow hematopoietic stem cells (HSCs) (c-Kit(+)Lin(-)), granulocyte-macrophage progenitors (Gr1(+)Mac1(+)) and total bone marrow cellularity. In mice gavage-treated daily with 50mg/kg dose of CV for 10 days, concomitant to a continuous offering of 1300 ppm lead acetate in drinking water, the treatment with the algae recovered the significantly reduced numbers of these cell populations to control values. As CV may have a myelostimulating effect through the induction of cytokines, we evaluated its modulating effects on the production of IL-1α, TNF-α, IFN-γ, IL-10 and IL-6. Our results demonstrated that lead significantly impairs the production of IFN-γ, IL-1α and TNF-α and increases the production of IL-10 and IL-6 and that these effects are successfully modulated by the CV treatment. The activity of NK cells, reduced in Pb-exposed animals, was raised to levels higher than those of controls in the exposed group treated with CV. Treatment with the algae also stimulated the production of IFN-γ, IL-1α, TNF-α and NK cells activity in normal mice. In addition, zinc bone concentrations, reduced in lead-exposed mice, were partially, but significantly, reversed by the treatment with CV.492934-4
Myelopoiesis modulation by ACE hyperfunction in kinin B-1 receptor knockout mice: Relationship with AcSDKP levels
Angiotensin I-converting enzyme (ACE), a common element of renin-angiotensin system (RAS) and kallikrein-kinin system (KKS), is involved in myelopoiesis modulation, mainly by cleaving the tetrapeptide N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP). Based on this finding and in our results showing B1 and B2 kinin receptors expression in murine bone marrow (BM) cells, we evaluated the ACE influence on myelopoiesis of kinin B1 receptor knockout mice (B1KO) using long-term bone marrow cultures (LTBMCs). Captopril and AcSDKP were used as controls. Enhanced ACE activity, expressed by non-hematopoietic cells (Ter-199(-) and CD45(-)), was observed in B1KO LTBMCs when compared to wild-type (WT) cells. ACE hyperfunction in B1KO cells was maintained when LTBMCs from B1KO mice were treated with captopril (1.0 mu M) or AcSDKP (1.0 nM). Although no alterations were observed in ACE mRNA and protein levels under these culture conditions, 3.0 nM of AcSDKP increased ACE mRNA levels in WT LTBMCs. No alteration in the number of GM-CFC was seen in B1KO mice compared to WT animals, even when the former were treated with AcSDKP (10 mu g/kg) or captopril (100 mg/kg) for 4 consecutive days. Hematological data also revealed no differences between WT and B1KO mice under basal conditions. When the animals received 4 doses of lipopolysaccharide (LPS), a decreased number of blood cells was detected in B1KO mice in relation to WT. We also found a decreased percentage of Gr1(+)/Mac-1(+), Ter119(+), B220(+), CD3(+), and Lin(-)Sca-1(+)c-Kit(+) (LSK) cells in the BM of B1KO mice compared to WT animals. Low AcSDKP levels were observed in BM cultures from B1KO in comparison to WT cultures. We conclude that ACE hyperfunction in B1KO mice resulted in faster hydrolysis of AcSDKP peptide, which in turn decreased in BM tissues allowing HSC to enter the S stage of the cell cycle. (C) 2010 Elsevier Ireland Ltd. All rights reserved,Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq)Universidade Federal de São Paulo, Dept Biofis, Escola Paulista Med, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Farmacol, Escola Paulista Med, BR-04040020 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Bioquim, Escola Paulista Med, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biofis, Escola Paulista Med, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Farmacol, Escola Paulista Med, BR-04040020 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Bioquim, Escola Paulista Med, São Paulo, BrazilFAPESP: 06/57253-4Web of Scienc