scholarly journals miR-146a attenuates apoptosis and modulates autophagy by targeting TAF9b/P53 pathway in doxorubicin-induced cardiotoxicity

2019 ◽  
Vol 10 (9) ◽  
Author(s):  
Jian-An Pan ◽  
Yong Tang ◽  
Jian-Ying Yu ◽  
Hui Zhang ◽  
Jun-Feng Zhang ◽  
...  
Keyword(s):  
Protective Factor ◽  
Low Dose ◽  
Tata Binding Protein ◽  
Wild Type ◽  
P53 Pathway ◽  
The Stability ◽  
Dose Dependent

Abstract Clinical therapy of doxorubicin (DOX) is limited due to its cardiotoxicity. miR-146a was proved as a protective factor in many cardiovascular diseases, but its role in chronic DOX-induced cardiotoxicity is unclear. The objective of this study was to demonstrate the role of miR-146a in low-dose long-term DOX-induced cardiotoxicity. Experiments have shown that DOX intervention caused a dose-dependent and time-dependent cardiotoxicity involving the increased of apoptosis and dysregulation of autophagy. The cardiotoxicity was inhibited by overexpressed miR-146a and was more severe when miR-146a was downgraded. Further research proved that miR-146a targeted TATA-binding protein (TBP) associated factor 9b (TAF9b), a coactivator and stabilizer of P53, indirectly destroyed the stability of P53, thereby inhibiting apoptosis and improving autophagy in cardiomyocytes. Besides, miR-146a knockout mice were used for in vivo validation. In the DOX-induced model, miR-146a deficiency made it worse whether in cardiac function, cardiomyocyte apoptosis or basal level of autophagy, than wild-type. In conclusion, miR-146a partially reversed the DOX-induced cardiotoxicity by targeting TAF9b/P53 pathway to attenuate apoptosis and adjust autophagy levels.

The Role of the cGMP-Dependent Protein Kinase II in Platelet Activation and In Vivo Thrombosis.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 653-653
Author(s):  
Zhenyu Li ◽  
Guoying Zhang ◽  
Hong Yin ◽  
Robert Feil ◽  
Franz Hofmann ◽  
...  
Keyword(s):  
Platelet Activation ◽  
Low Dose ◽  
Bleeding Time ◽  
Wild Type ◽  
Rt Pcr ◽  
Dependent Protein Kinase ◽  
Cgmp Dependent Protein Kinase ◽  
Dependent Protein

Abstract Although it was previously believed that the intracellular secondary messenger cGMP inhibits platelets, we have recently shown that cGMP-dependent protein kinase I (PKG I) in fact plays a stimulatory role in platelet activation. However, there are apparent differences between the PKG inhibitors and PKG I knockout in their effects on platelet activation. PKG inhibitors are more potent in inhibiting platelet activation than PKG I knockout. More importantly, although platelet secretion and aggregation induced by collagen were inhibited by PKG inhibitors, they are not significantly affected in PKG I knockout platelets. There are two types of PKG, PKG I and PKG II. PKG II has not been previously described in platelets. Here we show that PKG II mRNA is expressed in platelets using RT-PCR with primers specific for a C-terminal fragment of human PKG II cDNA. We further cloned the complete cDNA of human PKG II by RT-PCR using the purified human platelet mRNA as a template. Furthermore, PKG II from platelet lysates was pulled down by cGMP conjugated agarose beads and detected by western blot using a polyclonal antibody against PKG II. These data indicate that PKG II is expressed in platelets. To investigate the role of PKG II in platelet activation, washed wild type or PKG II knockout (PKG II−/−) mouse platelets in tyrode’s solution were exposed to platelet agonists. Platelet aggregation and ATP secretion induced by low concentrations of collagen were significantly reduced in PKG II deficient mice, indicating that PKG II plays important roles in collagen-induced platelet activation. PKG II−/− platelets also showed reduced aggregation and secretion to low dose of a thromboxane A2 (TXA2) analog, U46619. However, low dose thrombin-induced platelet activation was not negatively affected in PKG II−/− platelets, but was inhibited in PKG I−/− platelets. To evaluate the in vivo role of PKG II, we compared in vivo thrombus formation of wild type and PKG II knockout mice using the FeCl3-injured carotid artery thrombosis model. The time to the formation of stable thrombus in PKG II−/− mice (median, 420.0 seconds, n=15) is significantly prolonged compared to wild type mice (median, 321.0 seconds, n=15) (p=0.031). Tail-bleed time analysis also indicated a remarkably prolonged bleeding time in PKG II−/− mice (the median bleeding time was 73.50 seconds (n=18) in wild type mice, 454.50 seconds (n=20) in PKG II knockout mice) (p=0.0008). Thus, PKG II plays an important role in promoting platelet activation, thrombosis and hemostasis. PKG I and PKG II have differential roles in platelet activation induced by different platelet agonists.

scholarly journals The Role of Apoptosis in the Regulation of Hematopoietic Stem Cells

2000 ◽  
Vol 191 (2) ◽  
pp. 253-264 ◽  
Author(s):  
Jos Domen ◽  
Samuel H. Cheshier ◽  
Irving L. Weissman
Keyword(s):  
Stem Cells ◽  
Hematopoietic Stem Cells ◽  
Hematopoietic Cells ◽  
Wild Type ◽  
Direct Role ◽  
Hematopoietic Stem

Hematopoietic stem cells (HSC) give rise to cells of all hematopoietic lineages, many of which are short lived. HSC face developmental choices: self-renewal (remain an HSC with long-term multilineage repopulating potential) or differentiation (become an HSC with short-term multilineage repopulating potential and, eventually, a mature cell). There is a large overcapacity of differentiating hematopoietic cells and apoptosis plays a role in regulating their numbers. It is not clear whether apoptosis plays a direct role in regulating HSC numbers. To address this, we have employed a transgenic mouse model that overexpresses BCL-2 in all hematopoietic cells, including HSC: H2K-BCL-2. Cells from H2K-BCL-2 mice have been shown to be protected against a wide variety of apoptosis-inducing challenges. This block in apoptosis affects their HSC compartment. H2K-BCL-2–transgenic mice have increased numbers of HSC in bone marrow (2.4× wild type), but fewer of these cells are in the S/G2/M phases of the cell cycle (0.6× wild type). Their HSC have an increased plating efficiency in vitro, engraft at least as well as wild-type HSC in vivo, and have an advantage following competitive reconstitution with wild-type HSC.

Catecholamines act via a β-adrenergic receptor to maintain fetal heart rate and survival

2003 ◽  
Vol 284 (6) ◽  
pp. H2069-H2077 ◽  
Author(s):  
Andrea L. Portbury ◽  
Rashmi Chandra ◽  
Marybeth Groelle ◽  
Michael K. McMillian ◽  
Alana Elias ◽  
...  
Keyword(s):  
Heart Rate ◽  
Fetal Heart Rate ◽  
Adrenergic Receptor ◽  
Fetal Heart ◽  
Wild Type ◽  
Reduce Heart Rate ◽  
Specific Manner ◽  
Dose Dependent

Mice lacking catecholamines die before birth, some with cardiovascular abnormalities. To investigate the role of catecholamines in development, embryonic day 12.5 (E12.5) fetuses were cultured and heart rate monitored. Under optimal oxygenation, wild-type and catecholamine-deficient fetuses had the same initial heart rate (200–220 beats/min), which decreased by 15% in wild-type fetuses during 50 min of culture. During the same culture period, catecholamine-deficient fetuses dropped their heart rate by 35%. Hypoxia reduced heart rate of wild-type fetuses by 35–40% in culture and by 20% in utero, assessed by echocardiography. However, catecholamine-deficient fetuses exhibited greater hypoxia-induced bradycardia, reducing their heart rate by 70–75% in culture. Isoproterenol, a β-adrenergic receptor (β-AR) agonist, reversed this extreme bradycardia, restoring the rate of catecholamine-deficient fetuses to that of nonmutant siblings. Moreover, isoproterenol rescued 100% of catecholamine-deficient pups to birth in a dose-dependent, stereo-specific manner when administered in the dam's drinking water. An α-AR agonist was without effect. When wild-type fetuses were cultured with adrenoreceptor antagonists to create pharmacological nulls, blockade of α-ARs with 10 μM phentolamine or β-ARs with 10 μM bupranolol alone or in combination did not reduce heart rate under optimal oxygenation. However, when combined with hypoxia, β-AR blockade reduced heart rate by 35%. In contrast, the muscarinic blocker atropine and the α-AR antagonist phentolamine had no effect. These data suggest that β-ARs mediate survival in vivo and regulate heart rate in culture. We hypothesize that norepinephrine, acting through β-ARs, maintains fetal heart rate during periods of transient hypoxia that occur throughout gestation, and that catecholamine-deficient fetuses die because they cannot withstand hypoxia-induced bradycardia.

scholarly journals Antibody targeting KIT as pretransplantation conditioning in immunocompetent mice

Blood ◽  
2010 ◽  
Vol 116 (24) ◽  
pp. 5419-5422 ◽  
Author(s):  
Xingkui Xue ◽  
Nancy K. Pech ◽  
W. Christopher Shelley ◽  
Edward F. Srour ◽  
Mervin C. Yoder ◽  
...  
Keyword(s):  
Low Dose ◽  
Lentiviral Vector ◽  
Ex Vivo ◽  
Selective Advantage ◽  
Wild Type ◽  
Gene Correction ◽  
Hematopoietic Stem ◽  
Immunocompetent Mice

Abstract Inherited hematologic defects that lack an in vivo selective advantage following gene correction may benefit from effective yet minimally toxic cytoreduction of endogenous hematopoietic stem cells (HSCs) prior to transplantation of gene-modified HSCs. We studied the efficacy of administering a novel sequential treatment of parenteral ACK2, an antibody that blocks KIT, followed by low-dose irradiation (LD-IR) for conditioning of wild-type and X-linked chronic granulomatous disease (X-CGD) mice. In wild-type mice, combining ACK2 and LD-IR profoundly decreased endogenous competitive long-term HSC repopulating activity, and permitted efficient and durable donor-derived HSC engraftment after congenic transplantation. ACK2 alone was ineffective. The combination of ACK2 and LD-IR was also effective conditioning in X-CGD mice for engraftment of X-CGD donor HSCs transduced ex vivo with a lentiviral vector. We conclude that combining ACK2 with LD-IR is a promising approach to effectively deplete endogenous HSCs and facilitate engraftment of transplanted donor HSCs.

THE ROLE OF POLYETHYLENIMINE IN ENHANCING PERFORMANCE OF GLUTAMATE BIOSENSORS

2018 ◽  
Vol 8 (3) ◽  
pp. 36-41
Author(s):  
Diep Do Thi Hong ◽  
Duong Le Phuoc ◽  
Hoai Nguyen Thi ◽  
Serra Pier Andrea ◽  
Rocchitta Gaia
Keyword(s):  
First Generation ◽  
Good Reproducibility ◽  
Complex Matrices ◽  
Long Term Stability ◽  
In Vitro Characterization ◽  
Glutamate Oxidase

Background: The first biosensor was constructed more than fifty years ago. It was composed of the biorecognition element and transducer. The first-generation enzyme biosensors play important role in monitoring neurotransmitter and determine small quantities of substances in complex matrices of the samples Glutamate is important biochemicals involved in energetic metabolism and neurotransmission. Therefore, biosensors requires the development a new approach exhibiting high sensibility, good reproducibility and longterm stability. The first-generation enzyme biosensors play important role in monitoring neurotransmitter and determine small quantities of substances in complex matrices of the samples. The aims of this work: To find out which concentration of polyethylenimine (PEI) exhibiting the most high sensibility, good reproducibility and long-term stability. Methods: We designed and developed glutamate biosensor using different concentration of PEI ranging from 0% to 5% at Day 1 and Day 8. Results: After Glutamate biosensors in-vitro characterization, several PEI concentrations, ranging from 0.5% to 1% seem to be the best in terms of VMAX, the KM; while PEI content ranging from 0.5% to 1% resulted stable, PEI 1% displayed an excellent stability. Conclusions: In the result, PEI 1% perfomed high sensibility, good stability and blocking interference. Furthermore, we expect to develop and characterize an implantable biosensor capable of detecting glutamate, glucose in vivo. Key words: Glutamate biosensors, PEi (Polyethylenimine) enhances glutamate oxidase, glutamate oxidase biosensors

scholarly journals Arabidopsis Disulfide Reductase, Trx-h2, Functions as an RNA Chaperone under Cold Stress

2021 ◽  
Vol 11 (15) ◽  
pp. 6865
Author(s):  
Eun Seon Lee ◽  
Joung Hun Park ◽  
Seong Dong Wi ◽  
Ho Byoung Chae ◽  
Seol Ki Paeng ◽  
...  
Keyword(s):  
Cold Stress ◽  
Wild Type ◽  
Rna Chaperone ◽  
E Coli ◽  
Cold Sensitive ◽  
Thioredoxin H ◽  
Functional Rnas

The thioredoxin-h (Trx-h) family of Arabidopsis thaliana comprises cytosolic disulfide reductases. However, the physiological function of Trx-h2, which contains an additional 19 amino acids at its N-terminus, remains unclear. In this study, we investigated the molecular function of Trx-h2 both in vitro and in vivo and found that Arabidopsis Trx-h2 overexpression (Trx-h2OE) lines showed significantly longer roots than wild-type plants under cold stress. Therefore, we further investigated the role of Trx-h2 under cold stress. Our results revealed that Trx-h2 functions as an RNA chaperone by melting misfolded and non-functional RNAs, and by facilitating their correct folding into active forms with native conformation. We showed that Trx-h2 binds to and efficiently melts nucleic acids (ssDNA, dsDNA, and RNA), and facilitates the export of mRNAs from the nucleus to the cytoplasm under cold stress. Moreover, overexpression of Trx-h2 increased the survival rate of the cold-sensitive E. coli BX04 cells under low temperature. Thus, our data show that Trx-h2 performs function as an RNA chaperone under cold stress, thus increasing plant cold tolerance.

scholarly journals The Role of the Pathogen Dose and PI3Kγ in Immunometabolic Reprogramming of Microglia for Innate Immune Memory

2021 ◽  
Vol 22 (5) ◽  
pp. 2578
Author(s):  
Trim Lajqi ◽  
Christian Marx ◽  
Hannes Hudalla ◽  
Fabienne Haas ◽  
Silke Große ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Immune Tolerance ◽  
Immune Cells ◽  
Low Dose ◽  
Innate Immune ◽  
Immune Memory ◽  
Innate Immune Cells ◽  
Atp Production ◽  
Dose Dependent

Microglia, the innate immune cells of the CNS, exhibit long-term response changes indicative of innate immune memory (IIM). Our previous studies revealed IIM patterns of microglia with opposing immune phenotypes: trained immunity after a low dose and immune tolerance after a high dose challenge with pathogen-associated molecular patterns (PAMP). Compelling evidence shows that innate immune cells adopt features of IIM via immunometabolic control. However, immunometabolic reprogramming involved in the regulation of IIM in microglia has not been fully addressed. Here, we evaluated the impact of dose-dependent microglial priming with ultra-low (ULP, 1 fg/mL) and high (HP, 100 ng/mL) lipopolysaccharide (LPS) doses on immunometabolic rewiring. Furthermore, we addressed the role of PI3Kγ on immunometabolic control using naïve primary microglia derived from newborn wild-type mice, PI3Kγ-deficient mice and mice carrying a targeted mutation causing loss of lipid kinase activity. We found that ULP-induced IIM triggered an enhancement of oxygen consumption and ATP production. In contrast, HP was followed by suppressed oxygen consumption and glycolytic activity indicative of immune tolerance. PI3Kγ inhibited glycolysis due to modulation of cAMP-dependent pathways. However, no impact of specific PI3Kγ signaling on immunometabolic rewiring due to dose-dependent LPS priming was detected. In conclusion, immunometabolic reprogramming of microglia is involved in IIM in a dose-dependent manner via the glycolytic pathway, oxygen consumption and ATP production: ULP (ultra-low-dose priming) increases it, while HP reduces it.

scholarly journals A Replication-Defective Gammaherpesvirus Efficiently Establishes Long-Term Latency in Macrophages but Not in B Cells In Vivo

2008 ◽  
Vol 82 (17) ◽  
pp. 8500-8508 ◽  
Author(s):  
Haiyan Li ◽  
Kazufumi Ikuta ◽  
John W. Sixbey ◽  
Scott A. Tibbetts
Keyword(s):  
B Cells ◽  
Viral Genome ◽  
Lytic Replication ◽  
Mutant Virus ◽  
Wild Type Virus ◽  
Type Virus ◽  
Wild Type ◽  
Virus Latency

ABSTRACT Murine gammaherpesvirus 68 (γHV68 or MHV68) is genetically related to the human gammaherpesviruses Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV), providing a useful system for in vivo studies of the virus-host relationship. To begin to address fundamental questions about the mechanisms of the establishment of gammaherpesvirus latency, we previously generated a replication-defective γHV68 lacking the expression of the single-stranded DNA binding protein encoded by orf6. In work presented here, we demonstrate that this mutant virus established a long-term infection in vivo that was molecularly identical to wild-type virus latency. Thus, despite the absence of an acute phase of lytic replication, the mutant virus established a chronic infection in which the viral genome (i) was maintained as an episome and (ii) expressed latency-associated, but not lytic replication-associated, genes. Macrophages purified from mice infected with the replication-defective virus harbored viral genome at a frequency that was nearly identical to that of wild-type γHV68; however, the frequency of B cells harboring viral genome was greatly reduced in the absence of lytic replication. Thus, this replication-defective gammaherpesvirus efficiently established in vivo infection in macrophages that was molecularly indistinguishable from wild-type virus latency. These data point to a critical role for lytic replication or reactivation in the establishment or maintenance of latent infection in B cells.

Neurofilament phosphorylation

1995 ◽  
Vol 73 (9-10) ◽  
pp. 575-592 ◽  
Author(s):  
Harish C. Pant ◽  
Veeranna
Keyword(s):  
Molecular Weight ◽  
Nervous System ◽  
Nervous Tissue ◽  
Important Determinant ◽  
Neurofilament Proteins ◽  
Neurofilament Phosphorylation ◽  
Axonal Compartment

Neurofilament proteins (NFPs) are highly phosphorylated molecules in the axonal compartment of the adult nervous system. The phosphorylation of NFP is considered an important determinant of filament caliber, plasticity, and stability. This process reflects the function of NFs during the lifetime of a neuron from differentiation in the embryo through long-term activity in the adult until aging and environmental insult leads to pathology and ultimately death. NF function is modulated by phosphorylation–dephosphorylation in each of these diverse neuronal states. In this review, we have summarized some of these properties of NFP in adult nervous tissue, mostly from work in our own laboratory. Identification of sites phosphorylated in vivo in high molecular weight NFP (NF-H) and properties of NF-associated and neural-specific kinases phosphorylating specific sites in NFP are described. A model to explain the role of NF phosphorylation in determining filament caliber, plasticity, and stability is proposed.Key words: neurofilament proteins, phosphorylation, kinases, phosphatases, regulators, inhibitors, multimesic complex, domains.

scholarly journals Essential role of glucose transporter GLUT3 for post-implantation embryonic development

2008 ◽  
Vol 200 (1) ◽  
pp. 23-33 ◽  
Author(s):  
S Schmidt ◽  
A Hommel ◽  
V Gawlik ◽  
R Augustin ◽  
N Junicke ◽  
...  
Keyword(s):  
Essential Role ◽  
Glucose Transporter ◽  
Growth Arrest ◽  
Complete Loss ◽  
Transporter Gene ◽  
Wild Type ◽  
Post Implantation ◽  
Time Point

Deletion of glucose transporter geneSlc2a3(GLUT3) has previously been reported to result in embryonic lethality. Here, we define the exact time point of growth arrest and subsequent death of the embryo.Slc2a3−/−morulae and blastocysts developed normally, implantedin vivo, and formed egg-cylinder-stage embryos that appeared normal until day 6.0. At day 6.5, apoptosis was detected in the ectodermal cells ofSlc2a3−/−embryos resulting in severe disorganization and growth retardation at day 7.5 and complete loss of embryos at day 12.5. GLUT3 was detected in placental cone, in the visceral ectoderm and in the mesoderm of 7.5-day-old wild-type embryos. Our data indicate that GLUT3 is essential for the development of early post-implanted embryos.

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