scholarly journals Thrombopoietin Has Protective Effect in Neonatal Hypoxia-Ischemia Rat Model

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 4898-4898
Author(s):  
Liang Li ◽  
Liuming Yang ◽  
Hongwu Xin ◽  
Beng H Chong ◽  
Mo Yang
Keyword(s):  
Membrane Potential ◽  
Protective Effect ◽  
Brain Damage ◽  
Mitochondrial Membrane Potential ◽  
Rat Model ◽  
Mitochondrial Membrane ◽  
Conflicts Of Interest ◽  
Neonatal Rat ◽  
Neural Cells ◽  
Protective Effects

Thrombopoietin (TPO) is a growth factor for the megakaryocytic lineage. The expression of TPO and TPO receptor (c-mpl) in the central nervous system (CNS) and the role of TPO in neural cells and brain damage models were investigated. Our results showed the expression of TPO in human cerebral hemisphere, cerebellum, cerebrospinal fluid and blood plasma. We found that TPO had a protective effect in hypoxic-ischemic rat model, as indicated by the increased ipsilateral brain weight and neuron density in a neonatal rat model of hypoxic-ischemic brain damage. Recoveries of sensorimotor functions and histopathology were observed in these animals that received TPO. In addition, TPO could promote C17.2 cells proliferation by activating PI3K/Akt signaling pathway, and the proliferation could be reduced to nearly basal level by the pre-treatment with LY 294002. The phosphorylation of AKT, which is a hallmark of activation of each molecule was significantly enhanced after the treatment with TPO in the cells, peaking at 30 min after stimulation with TPO. TPO was also found to have an anti-apoptotic effect which mediated via Bcl-2/BAX and suppressing the mitochondrial membrane potential. Results showed the increased level of Bcl-2 and decreased level of BAX were in the time-dependence manner (0, 5, 15, 30 and 60 mins) in these cells. In addition, the mitochondrial membrane potential was significantly decreased by adding 100 ng/ml TPO. Our results indicated that TPO have neural protective effects. Disclosures No relevant conflicts of interest to declare.

Protective effect of the dimer of 16,16-diMePGB1 against KCN-induced mitochondrial failure in hepatocytes

1992 ◽  
Vol 263 (2) ◽  
pp. C405-C411 ◽  
Author(s):  
Y. Park ◽  
T. M. Devlin ◽  
D. P. Jones
Keyword(s):  
Membrane Potential ◽  
Protective Effect ◽  
Ion Transport ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Function ◽  
Mitochondrial Membrane ◽  
Time Dependent ◽  
Dependent Manner ◽  
Protective Effects ◽  
Cellular Swelling

The dimer and trimer of 16,16-dimethyl-15-dehydroprostaglandin B1 (16,16-diMePGB1) previously have been shown to have protective effects on mitochondrial function. To examine the potential mechanisms involved in protection against mitochondrial failure, we have studied the effects of the dimer of 16,16-diMe-PGB1 (dicalciphor) on mitochondrial function in hepatocytes exposed to KCN. Addition of micromolar concentrations of dicalciphor provided substantial protection against KCN-induced toxicity in a concentration- and time-dependent manner. Dicalciphor, however, had no effect on total or mitochondrial ATP losses in KCN-treated cells. The dimer prevented the marked loss of mitochondrial membrane potential (delta psi) and delta pH that occurs as a result of KCN treatment and prevented KCN-induced loading of phosphate in mitochondria. Furthermore, the dimer of 16,16-diMePGB1 also prevented KCN-induced mitochondrial and cellular swelling. These results demonstrate that dicalciphor protects against KCN-induced damage and that this protection is associated with regulation of specific mitochondrial ion transport functions.

Nanoparticles – a Novel Approach to Chronic Lymphocytic Leukemia Treatment?

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 4601-4601 ◽  
Author(s):  
Ida Franiak-Pietryga ◽  
Ewelina Ziolkowska ◽  
Barbara Ziemba ◽  
Dietmar Appelhans ◽  
Brigitte Voit ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Membrane Potential ◽  
Chronic Lymphocytic Leukemia ◽  
Mitochondrial Membrane Potential ◽  
Targeted Delivery ◽  
Mitochondrial Membrane ◽  
Conflicts Of Interest ◽  
Lymphocytic Leukemia ◽  
Amino Groups ◽  
Medical University

Abstract Abstract 4601 Treatment of chronic lymphocytic leukemia (CLL), including conventional therapy based on alkylating agents, purine nucleoside analogues (cladribine, fludarabine (FA)) or monoclonal antibodies (rituximab (Rit), alemtuzumab), significantly improved overall and complete responses. Although there are many treatment possibilities, this disease still remains incurable. Therefore, searching for new therapeutical strategies in CLL is vital. Nanotechnology, a new and promising field of scientific research, may be of use in medicine and the pharmaceutical industry. Dendrimers, nanoparticles (polymers) of dendritic architecture, used as carriers of drugs, nucleic acid and photosensitizers for targeted delivery, contrast agents in magnetic resonance imaging (MRI) have already been reported. It seems likely that dendrimers themselves might be damaging for neoplastic cells. The aim of our study was to preliminarly assess the clinical value of treating CLL patients with poly(propylene imine) (PPI) dendrimers. The assessment was based on the in vitro induction of cytotoxicity and apoptosis by fourth generation PPI dendrimers, with the surface amino groups substituted with maltotriose [Mal-III] residues. PPI-G4-OS-Mal-III dendrimers have, in contrast to the parental cationic PPI-G4, a virtually neutral surface charge. Therefore, they are preferentially involved in H-bond driven interactions. The study was conducted in 15 untreated CLL patients (7 men, 8 women) who were diagnosed in accordance with IWCLL criteria and followed at the Hematology Department, Medical University, Lodz, Poland. The Ethics Committee of the Medical University of Lodz, Poland approved the study (RNN/75/10/KE). Informed consent was obtained from all patients involved in the study. The mean age of CLL patients was 63.80 yrs. Peripheral blood mononuclear cells (MNCs) were separated from EDTA fresh blood. MNCs were incubated with dendrimers at concentrations of 4, 6 and 8 mg/ml. The cultures without dendrimers served as controls. Dendrimers in which approximately 35% of peripheral amino groups were coated with Mal-III (Leibniz Institute of Polymer Research, Dresden, Germany) have been defined as PPI-G4-OS-Mal-III. The abbreviation OS describes the open shell structure of carbohydrate-modified dendrimers (Fig. 1). The molar mass of this PPI dendrimer was 31000 g/mol. Apoptosis was measured by the Annexin-V/Propidium Iodide test. A decrease in mitochondrial membrane potential (one of the earliest events in the apoptotic pathway) was evaluated by the CMXRos technique, using flow cytometry. The percentage of cells with lower mitochondrial membrane potential (MMP) (DYmlow/Gly-A−) was determined. The percentage of apoptotic MNCs induced by PPI-G4-OS-Mal-III after 24 h and 48 h incubations was significantly higher than the percentage of spontaneous apoptotic leukemic cells. PPI glycodendrimers induced MNC apoptosis to a greater degree after 48 h than 24 h. The largest differences were observed for Ann-V+JP+ cells at a concentration of 8 mg/ml (p = 0.007). The IC50 value after 48-h-incubation was calculated as 8.24 mg/ml. Moreover, the CMXRos technique revealed apoptosis induction by PPI-G4-OS-Mal-III at each examined concentration in comparison with control cultures (Table 1). Table 1. 24h Control PPI-G4-OS-Mal-III 4 mg/ml PPI-G4-OS-Mal-III 6 mg/ml PPI-G4-OS-Mal-III 8 mg/ml FA 1.6 μM Rit 10 μg/ml X 23.7 51.0 60.1 64.4 62.9 28.0 48h X 28.3 67.8 71.9 79.3 89.0 29.4 X – mean percentage of cells with lower mitochondrial potential (DYmlow/Gly-A− [%]) Finally, PPI-G4-OS-Mal-III was not observed to have any harmful effects on erythrocytes (RBCs) or platelets (PLTs). The studied dendrimer induced PLT aggregation at a concentration of 50 mg/ml. Hemolysis induced by the PPI-G4-OS-Mal-III dendrimer is not important from the biological point of view. To summarise, the PPI-G4-OS-Mal-III dendrimer demonstrated higher cytotoxicity towards CLL cells than healthy donor cells. Its potency to trigger apoptosis is similar to many PNAs and monoclonal antibodies widely used in CLL therapy. Thus, dendrimers are a potential tool for CLL treatment. The study was partially supported by Grant No. DEC-2011/01/B/NZ5/01371 from the National Science Centre, Poland. Fig. 1. Fig. 1. Disclosures: No relevant conflicts of interest to declare.

Thrombopoietin Has Neural Protective Effect in a Neonatal Rat Model of Hypoxic-Ischemic Brain Damage

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 5059-5059 ◽  
Author(s):  
Mo Yang ◽  
Lei Liu ◽  
Enyu Liang ◽  
Beng H Chong ◽  
Chunfu Li
Keyword(s):  
Brain Damage ◽  
Rat Model ◽  
Akt Signaling ◽  
Cerebral Hemispheres ◽  
Neonatal Rat ◽  
Neural Cells ◽  
Rt Pcr ◽  
Hematopoietic Growth Factors ◽  
Neonatal Rat Model

Abstract Objective: The infusion of bone marrow cells into the damaged brain has been proposed as a new clinical practice for this disorder. Alternatively, hematopoietic growth factors may have a direct role on neural protection or have a mobilizing effect on bone marrow stem/progenitor cells to circulation for brain repair. Based on our previous findings, there are many similarities between megakaryocytes and neurons on functions and antigen expression such as neural marker MAP2, GFAP and Tau, 5-HT2A, 2B and 2C receptors (Stem Cells, 2014). Thrombopoietin (TPO) is a growth factor for megakaryocytic lineage. We postulate that TPO may play a role on neural protection or regeneration. The effect of TPO on nervous system has not been well investigated. Methods: To validate this hypothesis, we investigated the expression and role of TPO/TPO receptors in neural cells and a neonatal rat model of hypoxic-ischemic (HIE) brain damage. Results: To investigate the effect of TPO on in-vivo neural protection, a neonatal rat model of HIE brain damage was established. Brain injury was measured by the percentage weight reduction of the ipsilateral cerebral hemisphere as compared to the contralateral hemisphere. There was significantly less brain atrophy in TPO treated animals (12.0±1.2% and 11.5±1.0%) when compared with the saline control (21.0±1.6% and 24.4±2.2%) at 7 and 28 days post-operation (P<0.05, n=12). The percentage of NSE (Neuron-specific enolase) positive cells in the forelimb area of the cortex in the right hemisphere was significantly higher in the TPO group than that of the saline group (P<0.05, n=12). An improvement in sensory motor functions was also demonstrated after TPO treatment. TPO mRNA was also identified in human cerebral hemispheres, cerebellum, and mouse neural stem cell line C17.2 by RT-PCR methods. TPO protein was detected in human cerebrospinal fluids (n=10) by ELISA. Moreover, TPO receptor (c-mpl) mRNA was identified in human cerebral hemispheres and cerebellum, and C17.2 cells using RT-PCR. The expression of c-mpl protein was also confirmed on neurons in the human cerebral hemispheres, hippocampus, cerebellum, brainstem and spinal cord using immune-cytochemical staining. TPO also showed a stimulating effect on the in-vitro growth of C17.2 cells by the MTT assay. TPO activated the phosphoinositide 3-kinase(PI3K)/Akt signaling pathway which was demonstrated by Western blot. The Akt activation by TPO was inhibited by the PI3-kinase inhibitor LY294002. Conclusions: Our study provided the evidences showing the expression of TPO and TPO receptor (c-mpl) in neural cells and this effect may be mediated by c-mpl and Akt signaling. More importantly, our observation further demonstrated the functional role of TPO on neural protection in a rat model. These findings point to the possibility of a new strategy for treating brain damage by hematopoietic growth factors. Disclosures Yang: National Natural Science Foundation of China: Other: National Natural Science Foundation of China(81270580).

GATA-4 protects against hypoxia-induced cardiomyocyte injury: effects on mitochondrial membrane potential

2014 ◽  
Vol 92 (8) ◽  
pp. 669-678 ◽  
Author(s):  
Hong-Xia Li ◽  
Ya-Feng Zhou ◽  
Xin Zhao ◽  
Bin Jiang ◽  
Xiang-Jun Yang
Keyword(s):  
Bone Marrow ◽  
Membrane Potential ◽  
Growth Factor ◽  
Mitochondrial Membrane Potential ◽  
Neutralizing Antibodies ◽  
Mitochondrial Membrane ◽  
Annexin V ◽  
Neonatal Rat ◽  
Low Oxygen ◽  
Cell Protection

Our previous studies have suggested that GATA-4 increases the differentiation of bone-marrow-derived mesenchymal stem cells (MSCs) into cardiac phenotypes. This study further investigated whether GATA-4 enhances MSC-mediated cardioprotection following hypoxia. MSCs were harvested from rat bone marrow and transduced with GATA-4 (MSCGATA-4). To mimic ischemic injury, cultured cardiomyocytes (CMs) isolated from neonatal rat ventricles were exposed to hypoxia or were pretreated with concentrated conditioned medium (CdM) from MSCGATA-4 or transduced control MSC (MSCNull) for 16 h before exposure to hypoxic culture conditions (low glucose and low oxygen). Myocyte damage was estimated by annexin-V-PE and TUNEL technique and by lactate dehydrogenase (LDH) release. Cell survival was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium (MTT) uptake. Mitochondrial membrane potential was determined using confocal microscopy. ELISA studies indicated that insulin-like growth factor 1 (IGF-1) and vascular endothelial growth factor (VEGF) were significantly increased in MSCGATA-4 compared with MSCNull. Hypoxia-induced apoptosis/cell death was significantly reduced when CMs were co-cultured with MSCGATA-4 in a dual-chamber system. Cell protection mediated by MSCGATA-4 was mimicked by treating CMs with CdM from MSCGATA-4 and abrogated with IGF-1- and VEGF-neutralizing antibodies. MSCGATA-4 protects CMs under hypoxic conditions. The release of IGF-1 and VEGF from MSCGATA-4 is likely to be responsible for protection of CMs.

scholarly journals Hydrogen-Rich Medium Ameliorates Lipopolysaccharides-Induced Mitochondrial Fission and Dysfunction in Human Umbilical Vein Endothelial Cells (Huvecs) via Up-Regulating HO-1 Expression

2021 ◽  
Author(s):  
Keliang Xie ◽  
Xing Mao ◽  
Naqi Lian ◽  
Yanyan Wang ◽  
Yuzun Wang ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Membrane Potential ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Umbilical Vein ◽  
Mitochondrial Fission ◽  
Protective Effects ◽  
Atp Content ◽  
Rich Medium ◽  
Umbilical Vein Endothelial Cells

Abstract Background Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. It has been showed that the change of mitochondrial dynamics has been proved to be one of the main causes of death in patients with severe sepsis. And hydrogen has been proved to exert its protective effects against sepsis via heme oxygenase-1 (HO-1). This study was designed to demonstrate that whether the benefit effects of hydrogen can maintain the dynamic process of mitochondrial fusion/fission to mitigate human umbilical vein endothelial cells (HUVECs) injury exposed to endotoxin through HO-1. Methods HUVECs cells cultured with medium which contained Lipopolysaccharides (LPS), Saline, hydrogen, Mdivi-1 (a dynamin-related protein 1 [Drp1] inhibitor) or zinc protoporphyrin Ⅸ (Znpp) (a HO-1 inhibitor) were also used in the research. Cell death and apoptosis were assessed using FITC annexin V and PI. Mitochondria were stained with Mitotracker orange and observed by confocal microscope. Oxygen consumption rate was assessed by seahorse xf24 extracellular analyzer. Mitochondrial membrane potential monitored by JC-1 dye. The expressions of Drp1 and HO-1 were tested by Western blot. The co-localization of Drp1 and mitochondria was determined by immunofluorescence. Results LPS caused a decrease in ATP content, mitochondrial membrane potential, and maximal respiration rate. At the same time, increased expression of Drp1 were observed in LPS-stimulated HUVECs, concomitantly with excessive mitochondrial fission. We found that hydrogen-rich medium can increase ATP content, mitochondrial membrane potential and maximal respiration rate, and decrease the expression of Drp1 in LPS-treated HUVECs. Meanwhile, hydrogen can ameliorate excessive mitochondrial fission caused by LPS. Furthermore, hydrogen-rich medium had a similar effect to Mdivi-1, a mitochondrial fission blocker. Both of them rescued the up-regulation of Drp1 and mitochondrial fission induced by LPS, then normalized mitochondrial shape after LPS stimulation. But after Znpp pretreatment, HO-1 expression was inhibited and the protective effects of hydrogen were abrogated. Conclusions Hydrogen-rich medium can alleviate the LPS-induced mitochondrial fusion/fission and dysfunction in HUVECs via HO-1 up-regulation.

atpif1 regulates Mitochondrial Heme Synthesis In Developing Erythroid Cells

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 163-163
Author(s):  
Dhvanit I Shah ◽  
Naoko Takahasi-Makise ◽  
Iman Schultz ◽  
Eric L Pierce ◽  
Liangtao Li ◽  
...  
Keyword(s):  
Membrane Potential ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Positional Cloning ◽  
Conflicts Of Interest ◽  
Microcytic Anemia ◽  
Mitochondrial Atpase ◽  
Cluster Assembly ◽  
Inner Mitochondrial Membrane ◽  
Heme Synthesis

Abstract Abstract 163 Iron plays a key role as a cofactor in many fundamental metabolic processes, which require heme synthesis and Fe/S cluster assembly in the mitochondria. Defects in the transport of iron into the mitochondria would lead to anemias due to a deficiency in heme and hemoglobin synthesis. Here we describe a zebrafish genetic mutant, pinotage (pnttq209), which exhibits a profound hypochromic, microcytic anemia. Erythrocytes from pnt mutants have a defect in hemoglobinization and decreased red cell indices (mean corpuscular volume and hemoglobin content, hematocrit, hemoglobin concentration). Through positional cloning, we showed that the mitochondrial ATPase Inhibitory Factor 1 (atpif1), which regulates the inner mitochondrial membrane potential, is the gene disrupted in pnt. The identity of the pnt gene was verified by: (a) decreased atpif1 steady-state mRNA in pnt mutants, (b) phenocopying the anemia with anti-sense atpif1 morpholinos, (c) functional complementation of the anemia with atpif1 cRNA, and (d) a genetic polymorphism in the 3'UTR co-segregating with the mutant phenotype that destabilizes the atpif1 mRNA. Consistent with the conserved function of atpif1 in higher vertebrates, the silencing of the murine ortholog of atpif1 in Friend mouse erythroleukemia (MEL) cells showed a defect in hemoglobinization by o-dianisidine staining and reduction of 59Fe incorporation into heme in 59Fe-metabolically labeled cells. Moreover, Atpif1 knockdown destabilizes their mitochondrial membrane potential and volume. Therefore, the identification of atpif1 in pnt functionally demonstrates the role of atpif1 in regulating the proton motive gradient across the inner mitochondrial membrane for mitochondrial iron incorporation in heme biosynthesis. These results uncover a novel hematopoiesis-related function of atpif1, which will directly contribute to our understanding and potential treatment of human congenital and acquired anemias. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Thrombopoietin Protects Cardiomyocytes from Iron-Overload Induced Oxidative Stress and Mitochondrial Injury

2015 ◽  
Vol 36 (5) ◽  
pp. 2063-2071 ◽  
Author(s):  
Shing Chan ◽  
Godfrey Chifung Chan ◽  
Jieyu Ye ◽  
Qizhou Lian ◽  
Jianliang Chen ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Membrane Potential ◽  
Iron Overload ◽  
Protective Effect ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Lipid Hydroperoxides ◽  
Ros Production ◽  
H9c2 Cells ◽  
Induced Apoptosis

Background/Aims: Thalassaemia accompanied with iron-overload is common in Hong Kong. Iron-overload induced cardiomyopathy is the commonest cause of morbidity and mortality in patients with β-thalassaemia. Chronic iron-overload due to blood transfusion can cause cardiac failure. Decreased antioxidant defence and increased ROS production may lead to oxidative stress and cell injury. Iron-overload may lead to heart tissue damage through lipid peroxidation in response to oxidative stress, and a great diversity of toxic aldehydes are formed when lipid hydroperoxides break down in heart and plasma. Methods: Iron entry into embryonic heart H9C2 cells was determined by calcein assay using a fluorometer. Reactive oxygen species (ROS) production in cells treated with FeCl3 or thrombopoietin (TPO) was monitored by using the fluorescent probe H2DCFDA. Changes in mitochondrial membrane potential of H9C2 cells were quantified by using flow cytometry. Results: We demonstrated that iron induced oxidative stress and apoptosis in cardiomyocytes, and that iron increased ROS production and reduced cell viability in a dose-dependent manner. Iron treatment increased the proportion of cells with JC-1 monomers, indicating a trend of drop in the mitochondrial membrane potential. TPO exerted a cardio-protective effect on iron-induced apoptosis. Conclusions: These findings suggest that iron-overload leads to the generation of ROS and further induces apoptosis in cardiomyocytes via mitochondrial pathways. TPO might exert a protective effect on iron-overload induced apoptosis via inhibiting oxidative stress and suppressing the mitochondrial pathways in cardiomyocytes.

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