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1.
ACS Biomater Sci Eng ; 5(8): 3935-3943, 2019 08 12.
Article in English | MEDLINE | ID: mdl-31723595

ABSTRACT

Directed collective cell migration governs cell orientation during tissue morphogenesis, wound healing, and tumor metastasis. Unfortunately, current methods for initiating collective cell migration, such as scratching, laser ablation, and stencils, either introduce uncontrolled cell-injury, involve multiple fabrication processes, or have utility limited to cells with strong cell-cell junctions. Using three-dimensional (3D) bioprinted gelatin methacryloyl (GelMA) micropatterns on temperature-responsive poly(N-isopropylacrylamide) (PNIPAm) coated interfaces, we demonstrate that directed injury-free collective cell migration could occur in parallel and perpendicular directions. After seeding cells, we created cell-free spaces between two 3D bioprinted GelMA micropatterns by lowering the temperature of PNIPAm interfaces to promote the cell detachment. Unlike conventional collective cell migration methods initiated by stencils, we observed well-organized cell migration in parallel and perpendicular to 3D bioprinted micropatterns as a function of the distance between 3D bioprinted micropatterns. We further established the utility of controlled collective cell migration for directed functional myotube formation using 3D bioprinted fingerprintlike micropatterns as well as iris musclelike concentric circular patterns. Our platform is unique for myoblast alignment and myotube formation because it does not require anisotropic guidance cues. Together, our findings establish how to achieve controlled collective cell migration, even at the macroscale, for tissue engineering and regeneration.

2.
J Vis Exp ; (153)2019 11 09.
Article in English | MEDLINE | ID: mdl-31762453

ABSTRACT

Hematopoietic stem progenitor cells (HSPCs) have distinct metabolic plasticity, which allows them to transition from their quiescent state to a differentiation state to sustain demands of the blood formation. However, it has been difficult to analyze the metabolic status (mitochondrial respiration and glycolysis) of HSPCs due to their limited numbers and lack of optimized protocols for non-adherent, fragile HSPCs. Here, we provide a set of clear, step-by-step instructions to measure metabolic respiration (oxygen consumption rate; OCR) and glycolysis (extracellular acidification rate; ECAR) of murine bone marrow-LineagenegSca1+c-Kit+ (LSK) HSPCs. This protocol provides a higher amount of LSK HSPCs from murine bone marrow, improves the viability of HSPCs during incubation, facilitates extracellular flux analyses of non-adherent HSPCs, and provides optimized injection protocols (concentration and time) for drugs targeting oxidative phosphorylation and glycolytic pathways. This method enables the prediction of the metabolic status and the health of HSPCs during blood development and diseases.


Subject(s)
Hematopoietic Stem Cells/metabolism , Animals , Cell Differentiation , Cell Respiration , Glycolysis , Hematopoietic Stem Cells/cytology , Mice , Mitochondria/metabolism , Oxidative Phosphorylation , Oxygen Consumption , Proto-Oncogene Proteins c-kit/metabolism
3.
Curr Opin Cell Biol ; 49: 108-115, 2017 12.
Article in English | MEDLINE | ID: mdl-29413969

ABSTRACT

PURPOSE OF REVIEW: The hierarchical nature of the hematopoietic system provides an ideal model system to illustrate the features of lineage tracing. We have outlined the utility of lineage tracing methods in establishing the origin and development of hematopoietic cells. RECENT FINDINGS: Methods such as CRISPR/Cas9, Polylox barcoding, and single-cell RNA-sequencing have improved our understanding of hematopoiesis. SUMMARY: This review chronicles the fate of the hematopoietic cells emerging from the mesoderm that subsequently develops into the adult blood lineages. Specifically, we explain classic techniques utilized in lineage tracing for the hematopoietic system, as well as novel state-of-the-art methods to elucidate clonal hematopoiesis and cell fate mapping at a single-cell level.


Subject(s)
Hematopoiesis/genetics , Hematopoietic Stem Cells/metabolism , Cell Differentiation , Humans
4.
Stem Cell Reports ; 7(4): 583-590, 2016 10 11.
Article in English | MEDLINE | ID: mdl-27693426

ABSTRACT

Transparency of the cornea is indispensable for optimal vision. Ocular trauma is a leading cause of corneal opacity, leading to 25 million cases of blindness annually. Recently, mesenchymal stem cells (MSCs) have gained prominence due to their inflammation-suppressing and tissue repair functions. Here, we investigate the potential of MSCs to restore corneal transparency following ocular injury. Using an in vivo mouse model of ocular injury, we report that MSCs have the capacity to restore corneal transparency by secreting high levels of hepatocyte growth factor (HGF). Interestingly, our data also show that HGF alone can restore corneal transparency, an observation that has translational implications for the development of HGF-based therapy.


Subject(s)
Cornea/physiology , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/metabolism , Regeneration , Animals , Cell Line , Cornea/cytology , Cornea/drug effects , Corneal Injuries/genetics , Corneal Injuries/metabolism , Corneal Injuries/pathology , Corneal Injuries/therapy , Fibroblasts , Gene Expression , Hepatocyte Growth Factor/genetics , Hepatocyte Growth Factor/metabolism , Hepatocyte Growth Factor/pharmacology , Humans , Interleukin-1beta/pharmacology , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/drug effects , Mice , Models, Animal , RNA, Small Interfering/genetics , Wound Healing
5.
J Vis Exp ; (112)2016 06 11.
Article in English | MEDLINE | ID: mdl-27341538

ABSTRACT

Surgical parabiosis of two animals of different genetic backgrounds creates a unique scenario to study cell-intrinsic versus cell-extrinsic roles for candidate genes of interest, migratory behaviors of cells, and secreted signals in distinct genetic settings. Because parabiotic animals share a common circulation, any blood or blood-borne factor from one animal will be exchanged with its partner and vice versa. Thus, cells and molecular factors derived from one genetic background can be studied in the context of a second genetic background. Parabiosis of adult mice has been  used extensively to research aging, cancer, diabetes, obesity, and brain development. More recently, parabiosis of zebrafish embryos has been used to study the developmental biology of hematopoiesis. In contrast to mice, the transparent nature of zebrafish embryos permits the direct visualization of cells in the parabiotic context, making it a uniquely powerful method for investigating fundamental cellular and molecular mechanisms. The utility of this technique, however, is limited by a steep learning curve for generating the parabiotic zebrafish embryos. This protocol provides a step-by-step method on how to surgically fuse the blastulae of two zebrafish embryos of different genetic backgrounds to investigate the role of candidate genes of interest. In addition, the parabiotic zebrafish embryos are tolerant to heat shock, making temporal control of gene expression possible. This method does not require a sophisticated set-up and has broad applications for studying cell migration, fate specification, and differentiation in vivo during embryonic development.


Subject(s)
Blastula , Animals , Cell Movement , Hematopoiesis , Mice , Parabiosis , Zebrafish
6.
Blood ; 126(26): 2811-20, 2015 Dec 24.
Article in English | MEDLINE | ID: mdl-26385351

ABSTRACT

Rare endothelial cells in the aorta-gonad-mesonephros (AGM) transition into hematopoietic stem cells (HSCs) during embryonic development. Lineage tracing experiments indicate that HSCs emerge from cadherin 5 (Cdh5; vascular endothelial-cadherin)(+) endothelial precursors, and isolated populations of Cdh5(+) cells from mouse embryos and embryonic stem cells can be differentiated into hematopoietic cells. Cdh5 has also been widely implicated as a marker of AGM-derived hemogenic endothelial cells. Because Cdh5(-/-) mice embryos die before the first HSCs emerge, it is unknown whether Cdh5 has a direct role in HSC emergence. Our previous genetic screen yielded malbec (mlb(bw306)), a zebrafish mutant for cdh5, with normal embryonic and definitive blood. Using time-lapse confocal imaging, parabiotic surgical pairing of zebrafish embryos, and blastula transplantation assays, we show that HSCs emerge, migrate, engraft, and differentiate in the absence of cdh5 expression. By tracing Cdh5(-/-)green fluorescent protein (GFP)(+/+) cells in chimeric mice, we demonstrated that Cdh5(-/-)GFP(+/+) HSCs emerging from embryonic day 10.5 and 11.5 (E10.5 and E11.5) AGM or derived from E13.5 fetal liver not only differentiate into hematopoietic colonies but also engraft and reconstitute multilineage adult blood. We also developed a conditional mouse Cdh5 knockout (Cdh5(flox/flox):Scl-Cre-ER(T)) and demonstrated that multipotent hematopoietic colonies form despite the absence of Cdh5. These data establish that Cdh5, a marker of hemogenic endothelium in the AGM, is dispensable for the transition of hemogenic endothelium to HSCs.


Subject(s)
Antigens, CD/metabolism , Cadherins/metabolism , Cell Differentiation/physiology , Hemangioblasts/cytology , Hematopoiesis/physiology , Hematopoietic Stem Cells/cytology , Animals , Cell Lineage/physiology , Electroporation , Embryo, Mammalian , Embryo, Nonmammalian , Flow Cytometry , Immunohistochemistry , Mesonephros/embryology , Mice , Mice, Knockout , Microscopy, Confocal , Zebrafish
7.
J Clin Invest ; 124(10): 4294-304, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25157825

ABSTRACT

The transport and intracellular trafficking of heme biosynthesis intermediates are crucial for hemoglobin production, which is a critical process in developing red cells. Here, we profiled gene expression in terminally differentiating murine fetal liver-derived erythroid cells to identify regulators of heme metabolism. We determined that TMEM14C, an inner mitochondrial membrane protein that is enriched in vertebrate hematopoietic tissues, is essential for erythropoiesis and heme synthesis in vivo and in cultured erythroid cells. In mice, TMEM14C deficiency resulted in porphyrin accumulation in the fetal liver, erythroid maturation arrest, and embryonic lethality due to profound anemia. Protoporphyrin IX synthesis in TMEM14C-deficient erythroid cells was blocked, leading to an accumulation of porphyrin precursors. The heme synthesis defect in TMEM14C-deficient cells was ameliorated with a protoporphyrin IX analog, indicating that TMEM14C primarily functions in the terminal steps of the heme synthesis pathway. Together, our data demonstrate that TMEM14C facilitates the import of protoporphyrinogen IX into the mitochondrial matrix for heme synthesis and subsequent hemoglobin production. Furthermore, the identification of TMEM14C as a protoporphyrinogen IX importer provides a genetic tool for further exploring erythropoiesis and congenital anemias.


Subject(s)
Erythropoiesis/genetics , Heme/metabolism , Mitochondria/metabolism , Mitochondrial Membrane Transport Proteins/metabolism , Anemia/metabolism , Animals , Cell Line , Erythroid Cells/metabolism , Gene Expression Regulation , Hemoglobins/metabolism , Liver/embryology , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mice , Mitochondrial Membrane Transport Proteins/genetics , Mitochondrial Membranes/metabolism , Porphyrins/metabolism , Protoporphyrins/metabolism , RNA, Small Interfering/metabolism
8.
Am J Hum Genet ; 93(5): 906-14, 2013 Nov 07.
Article in English | MEDLINE | ID: mdl-24119684

ABSTRACT

We used exome sequencing to identify mutations in sideroflexin 4 (SFXN4) in two children with mitochondrial disease (the more severe case also presented with macrocytic anemia). SFXN4 is an uncharacterized mitochondrial protein that localizes to the mitochondrial inner membrane. sfxn4 knockdown in zebrafish recapitulated the mitochondrial respiratory defect observed in both individuals and the macrocytic anemia with megaloblastic features of the more severe case. In vitro and in vivo complementation studies with fibroblasts from the affected individuals and zebrafish demonstrated the requirement of SFXN4 for mitochondrial respiratory homeostasis and erythropoiesis. Our findings establish mutations in SFXN4 as a cause of mitochondriopathy and macrocytic anemia.


Subject(s)
Anemia, Macrocytic/genetics , Membrane Proteins/genetics , Mitochondrial Diseases/genetics , Adolescent , Animals , Child , Erythropoiesis/genetics , Exome , Female , Gene Knockdown Techniques , Humans , Mitochondrial Proteins/genetics , Mutation , Zebrafish/genetics
9.
Cell Metab ; 17(3): 343-52, 2013 Mar 05.
Article in English | MEDLINE | ID: mdl-23416069

ABSTRACT

Sorting of endocytic ligands and receptors is critical for diverse cellular processes. The physiological significance of endosomal sorting proteins in vertebrates, however, remains largely unknown. Here we report that sorting nexin 3 (Snx3) facilitates the recycling of transferrin receptor (Tfrc) and thus is required for the proper delivery of iron to erythroid progenitors. Snx3 is highly expressed in vertebrate hematopoietic tissues. Silencing of Snx3 results in anemia and hemoglobin defects in vertebrates due to impaired transferrin (Tf)-mediated iron uptake and its accumulation in early endosomes. This impaired iron assimilation can be complemented with non-Tf iron chelates. We show that Snx3 and Vps35, a component of the retromer, interact with Tfrc to sort it to the recycling endosomes. Our findings uncover a role of Snx3 in regulating Tfrc recycling, iron homeostasis, and erythropoiesis. Thus, the identification of Snx3 provides a genetic tool for exploring erythropoiesis and disorders of iron metabolism.


Subject(s)
Anemia/genetics , Iron/metabolism , Receptors, Transferrin/metabolism , Sorting Nexins/metabolism , Analysis of Variance , Animals , Blotting, Western , Cells, Cultured , Fluorescein-5-isothiocyanate , Fluorescent Antibody Technique , Gene Silencing , Mice , Sorting Nexins/genetics , Zebrafish
10.
Dev Biol ; 373(2): 431-41, 2013 Jan 15.
Article in English | MEDLINE | ID: mdl-22960038

ABSTRACT

Growth Factor Independence (Gfi) transcription factors play essential roles in hematopoiesis, differentially activating and repressing transcriptional programs required for hematopoietic stem/progenitor cell (HSPC) development and lineage specification. In mammals, Gfi1a regulates hematopoietic stem cells (HSC), myeloid and lymphoid populations, while its paralog, Gfi1b, regulates HSC, megakaryocyte and erythroid development. In zebrafish, gfi1aa is essential for primitive hematopoiesis; however, little is known about the role of gfi1aa in definitive hematopoiesis or about additional gfi factors in zebrafish. Here, we report the isolation and characterization of an additional hematopoietic gfi factor, gfi1b. We show that gfi1aa and gfi1b are expressed in the primitive and definitive sites of hematopoiesis in zebrafish. Our functional analyses demonstrate that gfi1aa and gfi1b have distinct roles in regulating primitive and definitive hematopoietic progenitors, respectively. Loss of gfi1aa silences markers of early primitive progenitors, scl and gata1. Conversely, loss of gfi1b silences runx-1, c-myb, ikaros and cd41, indicating that gfi1b is required for definitive hematopoiesis. We determine the epistatic relationships between the gfi factors and key hematopoietic transcription factors, demonstrating that gfi1aa and gfi1b join lmo2, scl, runx-1 and c-myb as critical regulators of teleost HSPC. Our studies establish a comparative paradigm for the regulation of hematopoietic lineages by gfi transcription factors.


Subject(s)
DNA-Binding Proteins/genetics , Gene Expression Regulation, Developmental , Hematopoiesis/genetics , Zebrafish Proteins/genetics , Zebrafish/genetics , Amino Acid Sequence , Animals , Cloning, Molecular , Conserved Sequence/genetics , DNA-Binding Proteins/chemistry , DNA-Binding Proteins/metabolism , Embryo, Nonmammalian/metabolism , Epistasis, Genetic , Erythropoiesis/genetics , Evolution, Molecular , Hematopoietic Stem Cells/cytology , Hematopoietic Stem Cells/metabolism , Hematopoietic System/embryology , Hematopoietic System/metabolism , Models, Biological , Molecular Sequence Data , Zebrafish/embryology , Zebrafish Proteins/chemistry , Zebrafish Proteins/metabolism
11.
Nature ; 491(7425): 608-12, 2012 Nov 22.
Article in English | MEDLINE | ID: mdl-23135403

ABSTRACT

Defects in the availability of haem substrates or the catalytic activity of the terminal enzyme in haem biosynthesis, ferrochelatase (Fech), impair haem synthesis and thus cause human congenital anaemias. The interdependent functions of regulators of mitochondrial homeostasis and enzymes responsible for haem synthesis are largely unknown. To investigate this we used zebrafish genetic screens and cloned mitochondrial ATPase inhibitory factor 1 (atpif1) from a zebrafish mutant with profound anaemia, pinotage (pnt (tq209)). Here we describe a direct mechanism establishing that Atpif1 regulates the catalytic efficiency of vertebrate Fech to synthesize haem. The loss of Atpif1 impairs haemoglobin synthesis in zebrafish, mouse and human haematopoietic models as a consequence of diminished Fech activity and elevated mitochondrial pH. To understand the relationship between mitochondrial pH, redox potential, [2Fe-2S] clusters and Fech activity, we used genetic complementation studies of Fech constructs with or without [2Fe-2S] clusters in pnt, as well as pharmacological agents modulating mitochondrial pH and redox potential. The presence of [2Fe-2S] cluster renders vertebrate Fech vulnerable to perturbations in Atpif1-regulated mitochondrial pH and redox potential. Therefore, Atpif1 deficiency reduces the efficiency of vertebrate Fech to synthesize haem, resulting in anaemia. The identification of mitochondrial Atpif1 as a regulator of haem synthesis advances our understanding of the mechanisms regulating mitochondrial haem homeostasis and red blood cell development. An ATPIF1 deficiency may contribute to important human diseases, such as congenital sideroblastic anaemias and mitochondriopathies.


Subject(s)
Erythroblasts/metabolism , Erythropoiesis , Heme/biosynthesis , Mitochondria/metabolism , Mitochondrial Proteins/metabolism , Proteins/metabolism , Anemia, Sideroblastic/genetics , Anemia, Sideroblastic/metabolism , Anemia, Sideroblastic/pathology , Animals , Disease Models, Animal , Erythroblasts/cytology , Ferrochelatase/metabolism , Genetic Complementation Test , Humans , Hydrogen-Ion Concentration , Mice , Mitochondria/pathology , Mitochondrial Proteins/deficiency , Mitochondrial Proteins/genetics , Oxidation-Reduction , Proteins/genetics , Zebrafish/metabolism , ATPase Inhibitory Protein
12.
Blood ; 114(21): 4654-63, 2009 Nov 19.
Article in English | MEDLINE | ID: mdl-19729519

ABSTRACT

The nuclear protein FOG-1 binds transcription factor GATA-1 to facilitate erythroid and megakaryocytic maturation. However, little is known about the function of FOG-1 during myeloid and lymphoid development or how FOG-1 expression is regulated in any tissue. We used in situ hybridization, gain- and loss-of-function studies in zebrafish to address these problems. Zebrafish FOG-1 is expressed in early hematopoietic cells, as well as heart, viscera, and paraspinal neurons, suggesting that it has multifaceted functions in organogenesis. We found that FOG-1 is dispensable for endoderm specification but is required for endoderm patterning affecting the expression of late-stage T-cell markers, independent of GATA-1. The suppression of FOG-1, in the presence of normal GATA-1 levels, induces severe anemia and thrombocytopenia and expands myeloid-progenitor cells, indicating that FOG-1 is required during erythroid/myeloid commitment. To functionally interrogate whether GATA-1 regulates FOG-1 in vivo, we used bioinformatics combined with transgenic assays. Thus, we identified 2 cis-regulatory elements that control the tissue-specific gene expression of FOG-1. One of these enhancers contains functional GATA-binding sites, indicating the potential for a regulatory loop in which GATA factors control the expression of their partner protein FOG-1.


Subject(s)
Embryonic Development/physiology , Gene Expression Regulation, Developmental , Nuclear Proteins , Zebrafish Proteins , Zebrafish/embryology , Animals , GATA1 Transcription Factor/genetics , GATA1 Transcription Factor/metabolism , Hematopoiesis/physiology , In Situ Hybridization , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Oligonucleotide Array Sequence Analysis , Polymerase Chain Reaction , Regulatory Elements, Transcriptional/genetics , Zebrafish Proteins/genetics , Zebrafish Proteins/metabolism
13.
Bioorg Med Chem ; 16(24): 10210-5, 2008 Dec 15.
Article in English | MEDLINE | ID: mdl-19013821

ABSTRACT

A series of 5-alkylsulfamoyl benzimidazole derivatives have been designed and synthesized as novel angiotensin II (Ang II) receptor antagonists. The compounds have been evaluated for in vitro Ang II antagonism and for in vivo antihypertensive activity on isolated rat aortic ring and desoxycortisone acetate induced hypertensive rats, respectively. The activity is found related to size of alkyl group. The maximum activity is observed with a compact and bulky alkyl group like tert-butyl and cyclohexyl. The compounds 4g and 4h have shown promising both in vitro and in vivo activities. A receptor binding model is also proposed on the basis on the basis of structure-activity relationship in this study.


Subject(s)
Angiotensin II Type 2 Receptor Blockers , Antihypertensive Agents/chemical synthesis , Benzimidazoles/chemical synthesis , Benzimidazoles/pharmacology , Animals , Antihypertensive Agents/chemistry , Antihypertensive Agents/pharmacology , Benzimidazoles/chemistry , Blood Pressure/physiology , Drug Design , Rats , Receptor, Angiotensin, Type 2/metabolism
14.
Eur J Med Chem ; 43(9): 1808-12, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18158200

ABSTRACT

A series of 5-(alkyl and aryl)carboxamido benzimidazole derivatives had been designed, synthesized and evaluated for in vitro angiotensin II--AT1 receptor antagonism and in vivo antihypertensive activities. The pharmacological activities were inversely related to the size of alkyl and aryl substituents. It can be suggested that compounds with lower alkyl groups at 5-position of benzimidazole nucleus demonstrated potent antihypertensive activity.


Subject(s)
Angiotensin II Type 1 Receptor Blockers/chemical synthesis , Angiotensin II Type 1 Receptor Blockers/pharmacology , Benzimidazoles/chemical synthesis , Benzimidazoles/pharmacology , Drug Design , Receptor, Angiotensin, Type 1 , Angiotensin II Type 1 Receptor Blockers/chemistry , Angiotensin II Type 1 Receptor Blockers/therapeutic use , Animals , Antihypertensive Agents/chemical synthesis , Antihypertensive Agents/chemistry , Antihypertensive Agents/pharmacology , Antihypertensive Agents/therapeutic use , Benzimidazoles/chemistry , Benzimidazoles/therapeutic use , Hypertension/drug therapy , Rats , Reference Standards
15.
Int J Cardiol ; 120(3): 317-24, 2007 Sep 03.
Article in English | MEDLINE | ID: mdl-17240464

ABSTRACT

BACKGROUND: Activation of Akt stimulates phosphorylation of eNOS, production of nitric oxide and reduces oxidative stress. The study has been designed to investigate the effect of DAQ B1, an activator of Akt, in hypertension associated vascular endothelial dysfunction. METHODS: Rats were uninephroctomized and DOCA (40 mg kg(-1), s.c.) was administered to rats to produce hypertension (MABP>140 mm Hg). Vascular endothelial dysfunction was assessed using isolated aortic ring preparation, electron microscopy of thoracic aorta and serum concentration of nitrite/nitrate. The expression of messenger RNA for p22phox and eNOS was assessed by reverse transcription-polymerase chain reaction. Serum TBARS and aortic superoxide anion were estimated to assess oxidative stress. RESULTS: DAQ B1 (5 mg kg(-1), p.o.) or atorvastatin (30 mg kg(-1), p.o.) markedly improved acetylcholine induced endothelium dependent relaxation, vascular endothelial lining, expression of mRNA for eNOS and p22phox, serum nitrite/nitrate concentration and serum TBARS in hypertensive rats. However, this ameliorative effect of DAQ B1 has been prevented by L-NAME (25 mg kg(-1), i.p.), an inhibitor of eNOS. CONCLUSION: Therefore, it may be concluded that DAQ B1 induced activation of Akt may activate eNOS and consequently reduce oxidative stress to improve hypertension associated vascular endothelial dysfunction.


Subject(s)
Endothelium, Vascular/drug effects , Hypertension/drug therapy , Indoles/pharmacology , Animals , Aorta, Thoracic/metabolism , Aorta, Thoracic/pathology , Atorvastatin , Endothelium, Vascular/physiopathology , Heptanoic Acids/pharmacology , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology , Hypertension/physiopathology , Male , Microscopy, Electron , Muscle Relaxation/drug effects , Muscle, Smooth, Vascular/drug effects , NADPH Oxidases/metabolism , Nitrates/blood , Nitric Oxide Synthase Type III/metabolism , Nitrites/blood , Oxidative Stress , Pyrroles/pharmacology , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Superoxides/metabolism , Thiobarbituric Acid Reactive Substances/analysis
16.
Mol Cell Biochem ; 295(1-2): 65-74, 2007 Jan.
Article in English | MEDLINE | ID: mdl-16841179

ABSTRACT

The study has been designed to investigate the effect of demethylasterroquinone B1 (DAQ B1), an activator of Akt, in diabetes mellitus (DM) and hyperhomocysteinemia (HHcy)-induced vascular endothelial dysfunction. Streptozotocin (55 mg kg(-1), i.v.) and methionine (1.7% w/w, p.o., 4 weeks) were administered to rats to produce DM (serum glucose >140 mg dl(-1)) and HHcy (serum homocysteine >10 microM), respectively. Vascular endothelial dysfunction was assessed using isolated aortic ring preparation, electron microscopy of thoracic aorta and serum concentration of nitrite/nitrate. The expression of messenger RNA for p22phox and eNOS was assessed by reverse transcription-polymerase chain reaction. Serum thiobarbituric acid reactive substances (TBARS) and aortic superoxide anion were estimated to assess oxidative stress. DAQ B1 (5 mg kg(-1), p.o.) or atorvastatin (30 mg kg(-1), p.o.) in diabetic and hyperhomocysteinemic rats significantly reduced serum glucose and homocysteine concentration. DAQ B1 or atorvastatin markedly improved acetylcholine-induced endothelium-dependent relaxation, vascular endothelial lining, serum nitrite/nitrate concentration and serum TBARS in diabetic and hyperhomocysteinemic rats. However, this ameliorative effect of DAQ B1 has been prevented by L-NAME (25 mg kg(-1), i.p.), an inhibitor of eNOS. Therefore, it may be concluded that DAQ B1-induced activation of Akt may activate eNOS and consequently reduce oxidative stress to improve vascular endothelial dysfunction.


Subject(s)
Diabetes Mellitus, Experimental/enzymology , Diabetes Mellitus, Experimental/physiopathology , Endothelium, Vascular/enzymology , Endothelium, Vascular/physiopathology , Hyperhomocysteinemia/enzymology , Hyperhomocysteinemia/physiopathology , Proto-Oncogene Proteins c-akt/metabolism , Acetylcholine/pharmacology , Animals , Aorta/drug effects , Aorta/enzymology , Aorta/ultrastructure , Blood Glucose/metabolism , Diabetes Mellitus, Experimental/chemically induced , Endothelium, Vascular/ultrastructure , Gene Expression Regulation, Enzymologic/drug effects , Homocysteine/blood , Hyperhomocysteinemia/chemically induced , Male , NADPH Oxidases/genetics , NADPH Oxidases/metabolism , Nitrates/blood , Nitric Oxide Synthase Type III/genetics , Nitric Oxide Synthase Type III/metabolism , Nitrites/blood , Proto-Oncogene Proteins c-akt/agonists , Quinones/pharmacology , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Rats, Wistar , Superoxides/metabolism , Thiobarbituric Acid Reactive Substances/analysis , Vasodilation/drug effects
17.
Fundam Clin Pharmacol ; 20(6): 595-604, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17109653

ABSTRACT

The study has been designed to investigate the effect of 8-Br-cAMP, an activator of protein kinase A, in hypertension-induced vascular endothelial dysfunction. Rats were uninephroctomized and desoxycortisone acetate (DOCA) (40 mg/kg, s.c.) was administered to rats to produce hypertension (mean arterial blood pressure > 140 mmHg). Vascular endothelial dysfunction was assessed using isolated aortic ring preparation, electron microscopy of thoracic aorta and serum concentration of nitrite/nitrate. The expression of mRNA for p22phox and eNOS was assessed by using reverse transcriptase-polymerase chain reaction. Serum thiobarbituric acid reactive substances concentration and aortic superoxide anion concentration were estimated to assess oxidative stress. 8-Br-cAMP (5 mg/kg, i.p.) or atorvastatin (30 mg/kg, p.o.) prevented hypertension-induced attenuation of acetylcholine-induced endothelium-dependent relaxation, impairment of vascular endothelial lining, decrease in expression of mRNA for endothelial nitric oxide synthase (eNOS), serum nitrite/nitrate concentration and increase in expression of mRNA for p22phox, superoxide anion and serum TBARS. The ameliorative effect of 8-Br-cAMP was prevented by N-nitro-L-arginine methyl ester (25 mg/kg, i.p.) and glibenclamide (30 mg/kg, i.p.). It may be concluded that 8-Br-cAMP may stimulate expression and activity of eNOS and suppress expression of p22phox subunit of NADPH oxidase to reduce oxidative stress and subsequently improve vascular endothelial dysfunction.


Subject(s)
8-Bromo Cyclic Adenosine Monophosphate/pharmacology , Endothelium, Vascular/drug effects , Hypertension/drug therapy , 8-Bromo Cyclic Adenosine Monophosphate/administration & dosage , 8-Bromo Cyclic Adenosine Monophosphate/therapeutic use , Animals , Aorta/drug effects , Atorvastatin , Blood Pressure/drug effects , Cyclic AMP/blood , Drug Administration Schedule , Heptanoic Acids/administration & dosage , Hypertension/complications , Male , NADPH Oxidases/metabolism , Nitrates/blood , Nitric Oxide Synthase Type III/metabolism , Nitrites/blood , Pyrroles/administration & dosage , Rats , Rats, Sprague-Dawley , Superoxides/metabolism , Thiobarbituric Acid Reactive Substances/analysis , Vasodilation/drug effects
18.
Can J Physiol Pharmacol ; 84(8-9): 835-45, 2006.
Article in English | MEDLINE | ID: mdl-17111028

ABSTRACT

The present study has been designed to investigate the effect of fasudil (Rho-kinase inhibitor) in hypercholesterolemia- and hypertension-induced endothelial dysfunction. High fat diet (8 weeks) and desoxycortisone acetate (DOCA) (40 mg.kg-1) were administered (s.c.) to rats to produce hypercholesterolemia and hypertension (mean arterial blood pressure > 120 mmHg), respectively. Endothelial dysfunction was assessed using isolated aortic ring, electron microscopy of thoracic aorta, and serum concentration of nitrite/nitrate. The expression of mRNA for p22phox and eNOS was assessed by using RT-PCR. Serum thiobarbituric acid reactive substances concentration and aortic superoxide anion concentration were estimated to assess oxidative stress. Fasudil (30 mg.kg-1, p.o.) and atorvastatin (30 mg.kg-1, p.o.) treatments markedly prevented hypercholesterolemia- and hypertension-evoked attenuation of acetylcholine-induced endothelium-dependent relaxation, impairment of vascular endothelial lining, decrease in expression of mRNA for eNOS and serum nitrite/nitrate concentration, and an increase in expression of mRNA for p22phox, superoxide anion, and serum thiobarbituric acid reactive substances. The ameliorative effect of fasudil was prevented by L-NAME. In conclusion, fasudil-induced inhibition of Rho-kinase may improve hypercholesterolemia- and hypertension-induced endothelial dysfunction.


Subject(s)
1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine/analogs & derivatives , Hypercholesterolemia/drug therapy , Hypertension/drug therapy , Intracellular Signaling Peptides and Proteins/antagonists & inhibitors , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/antagonists & inhibitors , 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine/pharmacology , Acetylcholine/pharmacology , Animals , Aorta, Thoracic/drug effects , Aorta, Thoracic/metabolism , Aorta, Thoracic/physiopathology , Endothelium, Vascular/drug effects , Endothelium, Vascular/physiopathology , Hypercholesterolemia/physiopathology , Hypertension/chemically induced , Hypertension/physiopathology , In Vitro Techniques , Male , NADPH Oxidases/genetics , NADPH Oxidases/metabolism , Nitrates/blood , Nitric Oxide Synthase Type III/genetics , Nitric Oxide Synthase Type III/metabolism , Nitrites/blood , RNA, Messenger/analysis , Rats , Rats, Wistar , Superoxides/metabolism , Thiobarbituric Acid Reactive Substances/analysis , Vasodilation/drug effects , Vasodilator Agents/pharmacology , rho-Associated Kinases
19.
Endothelium ; 13(4): 267-77, 2006.
Article in English | MEDLINE | ID: mdl-16990183

ABSTRACT

The study has been designed to investigate the effect of 8-Br-cAMP, an activator of protein kinase A (PKA), in diabetes mellitus- and hyperhomocysteinemia-induced vascular endothelial dysfunction. Streptozotocin (55 mg kg-1, i.v.) and methionine (1.7% w/w, p.o., 4 weeks) were administered to rats to produce diabetes mellitus (serum glucose >200 mg dL-1) and hyperhomocysteinemia (serum homocysteine >10 microM), respectively. Vascular endothelial dysfunction was assessed using isolated aortic ring preparation, electron microscopy of thoracic aorta, and serum concentration of nitrite/nitrate. The expression of mRNA for p22phox and endothelial nitric oxide synthase (eNOS) was assessed by using reverse transcriptase-polymerase chain reaction (TBARS) (RT-PCR). Serum thiobarbituric acid-reactive substances (TBARS) concentration and aortic superoxide anion concentration were estimated to assess oxidative stress. 8-Br-cAMP (5 mg kg-1, i.p.) or atorvastatin (30 mg kg-1, p.o.) prevented diabetes mellitus- and hyperhomocysteinemia-induced attenuation of acetylcholine-induced endothelium-dependent relaxation, impairment of vascular endothelial lining, decrease in expression of mRNA for eNOS, serum nitrite/nitrate concentration, and increase in expression of mRNA for p22phox, superoxide anion, and serum TBARS. The ameliorative effect of 8-Br-cAMP was prevented by N omega-nitro-L-arginine methyl ester (L-NAME) (25 mg kg-1, i.p.) and glibenclamide (5 mg kg-1, i.p.). Therefore, it may be concluded that 8-Br-cAMP-induced activation of PKA may improve vascular endothelial dysfunction.


Subject(s)
Cyclic AMP-Dependent Protein Kinases/metabolism , Endothelium, Vascular/enzymology , Endothelium, Vascular/physiopathology , 8-Bromo Cyclic Adenosine Monophosphate/pharmacology , Animals , Blood Glucose/metabolism , Diabetes Mellitus, Experimental/enzymology , Diabetes Mellitus, Experimental/physiopathology , Endothelium, Vascular/drug effects , Homocysteine/blood , Homocysteine/metabolism , Hyperhomocysteinemia/enzymology , Hyperhomocysteinemia/physiopathology , Male , NADPH Oxidases/genetics , NADPH Oxidases/metabolism , Nitric Oxide Synthase Type III/genetics , Nitric Oxide Synthase Type III/metabolism , Nitrites/blood , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Superoxides/metabolism , Thiobarbituric Acid Reactive Substances/metabolism
20.
Naunyn Schmiedebergs Arch Pharmacol ; 373(3): 221-9, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16736159

ABSTRACT

The study has been designed to investigate the effect of bis(maltolato) oxovanadium (BMOV), a protein tyrosine phosphatase inhibitor, on hypercholesterolemia and hypertension-induced vascular endothelial dysfunction. High fat diet (8 weeks) and deoxycorticosterone acetate (DOCA; 40 mg kg(-1), s.c.) were administered to rats to produce hypercholesterolemia and hypertension (mean arterial blood pressure >120 mmHg) respectively. Vascular endothelial dysfunction was assessed using isolated aortic ring preparation, electron microscopy of thoracic aorta, and serum concentration of nitrite/nitrate. Serum thiobarbituric acid reactive substances (TBARS) were estimated to assess oxidative stress. BMOV (0.2 mg/ml in drinking water) or atorvastatin (30 mg kg(-1), p.o.) markedly improved acetylcholine-evoked endothelium-dependent relaxation, lining of vascular endothelium, serum nitrite/nitrate concentration, and serum TBARS in hypercholesterolemic and hypertensive rats. However, this ameliorative effect of BMOV has been prevented by L-NAME (25 mg kg(-1), i.p.), an inhibitor of NOS, or by glibenclamide (5 mg kg(-1), i.p.), a blocker of ATP-sensitive K(+) channels. It may be concluded that BMOV-induced inhibition of PTPase may improve vascular endothelial dysfunction.


Subject(s)
Pyrones/therapeutic use , Vanadates/therapeutic use , Vascular Diseases/drug therapy , Vascular Diseases/physiopathology , Animals , Blood Pressure/drug effects , Endothelins/pharmacology , Lipid Metabolism/drug effects , Male , Microscopy, Electron, Scanning , Nitrates/blood , Nitrites/blood , Pyrones/pharmacology , Rats , Rats, Sprague-Dawley , Thiobarbituric Acid Reactive Substances/metabolism , Vanadates/pharmacology , Vascular Diseases/pathology , Vasodilation/drug effects
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