Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.2.1.23 (beta-galactosidase)
14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Proline-rich tyrosine kinase 2 (PYK2) is a nonreceptor protein tyrosine kinase that links G-protein-coupled receptors to activation of MAPK cascades and cellular growth. In smooth muscle and other cell types, PYK2 activation is dependent on either Ca(2+) or protein kinase C (PKC), and we have previously shown that endothelin-1 (ET) activates PYK2 in adult and neonatal rat ventricular myocytes (NRVM). However, ET both alters intracellular Ca(2+) ([Ca(2+)](i)), and activates the novel, Ca(2+)-independent PKCs. Therefore, immunoprecipitation and western blotting experiments were used to examine the PKC and Ca(2+) dependence of PYK2 activation in NRVM. PYK2 was activated by ET (100 nM; 2-30 min) and phenylephrine (50 microM; 2-30 min), which are both hypertrophic agonists that activate Gq-coupled receptors. Moreover, adenoviral (Adv)-mediated overexpression of constitutively active (ca) Galphaq increased PYK2-Y(402) phosphorylation as early as 8 h post-infection, as compared to NRVM infected with a control Adv encoding beta-galactosidase. caGalphaq overexpression also induced PKC epsilon and PKCdelta (but not PKCalpha) translocation, followed by downregulation of both novel PKC isoenzymes. Phorbol myristate acetate (PMA; 200 nM), a direct activator of Ca(2+)-dependent and Ca(2+)-independent PKCs, activated PYK2 within 10 min, and PYK2 phosphorylation remained elevated after 30 min of stimulation. Adv-mediated overexpression of caPKC epsilon increased PYK2 phosphorylation, whereas Adv-mediated overexpression of a kinase-inactive mutant of PKC epsilon markedly inhibited ET-induced, but not basal PYK2 phosphorylation. In contrast, both basal and ET-induced PYK2 phosphorylation were blocked by treatment with the Src-family protein kinase inhibitor PP2. Although reducing [Ca(2+)](i) with either nifedipine (10 microM) or BAPTA-AM (50 microM) decreased basal PYK2 phosphorylation, it did not prevent ET-induced PYK2 activation. Furthermore, increasing [Ca(2+)](i) with ionomycin (10 microM), K(+) depolarization, or BayK8644 (1 microM) was not sufficient to further activate PYK2. These data demonstrate that ET-induced PYK2 activation is Gq, PKC epsilon, and Src dependent, describing a distinct signaling pathway leading to agonist-induced PYK2 activation in cardiomyocytes.
J Mol Cell Cardiol 2003 Sep
PMID:Protein kinase C epsilon-dependent activation of proline-rich tyrosine kinase 2 in neonatal rat ventricular myocytes. 1296 35

One of the major issues in myocardial gene therapy is poor transfection efficiency. The herpes simplex virus protein VP22 is known to facilitate intercellular protein transport. Not only VP22 but also VP22-linked protein are exported from the cytoplasm of cells, in which it is synthesised endogenously, and transferred to surrounding cells, where it is translocated into the nuclei. However, the feasibility and efficiency of the intercellular trafficking properties of VP22-linked protein in the myocardium has not been clarified. Rat hearts were transfected by direct intramyocardial injection of naked plasmid vectors encoding either lacZ or VP22-linked lacZ. At day 5 following transfection, similar numbers of cardiomyocytes surrounding the injection sites showed beta-galactosidase (beta-gal) expression in the cytoplasm in both groups. In addition to this, following transfection of VP22-linked lacZ, most of the cardiomyocytes adjacent to the cytoplasmic-positive cells demonstrated nuclear-localised beta-gal expression. The number of these nuclear-positive cardiomyocytes, which are thought to be secondary protein-transported cells, was 4.3-fold greater than that of primary transfected, cytoplasmic-positive cells. Western blot analysis demonstrated that the amount of targeted protein expression is 2.9-fold greater following VP22-lacZ transfection (VP22-linked beta-gal; approximately 40 kDa bigger than wild-type beta-gal) compared with lacZ transfection (wild-type beta-gal). This data highlights the efficiency of the VP22-mediated intercellular protein delivery in the myocardium following in vivo gene transfection and suggests that the VP22-mediated effect is useful in enhancing the efficacy of myocardial gene therapy.
J Mol Cell Cardiol 2004 Apr
PMID:Enhanced effect of myocardial gene transfection by VP22-mediated intercellular protein transport. 1508 20

Granulocyte-colony stimulating factor (G-CSF) has been reported to mobilize bone marrow multi-potent stem cells, which differentiate into cardiac myocytes after myocardial infarction (MI). However, there have not been any reports regarding the effect of G-CSF on stem cell infiltration in the MI site. Hearts of mice that had undergone coronary occlusion were isolated and digested with collagenase. Infiltrating cells in the heart were collected using Percoll density gradients. The infiltrating cells were sorted for side population (SP) cells using Hoechst 33342 dye. Hundreds of infiltrating SP cells were found in the heart from 1 to 14 d after MI. There were only a few SP cells in hearts without infarction. Infiltrating SP cells were increased in the 4-d G-CSF treated group compared with the vehicle group (1106 +/- 106 vs. 323 +/- 26/heart, P < 0.05). The infiltration of inflammatory cells was not influenced by the G-CSF treatment. In a separate series of experiments, we confirmed that the infiltrating SP cells were derived from bone marrow. That is, SP cells in the infarcted hearts of mice, which had been transplanted with bone marrow from ROSA 26 (beta-galactosidase transgenic) mice, were positive for beta-galactosidase. In the immunohistochemical examination, Sca-1(+)/CD45(-) cells were existed in the infarcted site after MI. Therefore, SP cells may infiltrate into infarcted heart. G-CSF augmented this kind of stem cell infiltration without increasing inflammatory cells. These results suggest that G-CSF may enhance myocardial regeneration without aggravated inflammation in the infarcted heart.
J Mol Cell Cardiol 2004 May
PMID:G-CSF treatment increases side population cell infiltration after myocardial infarction in mice. 1513 66

Gene therapy is emerging as a realistic addition to the therapeutic arsenal in heart failure, but the search for suitable vectors for cardiac transfection is still ongoing. In this study, we explore the applicability of recombinant Semliki Forest virus (SFV) in heart failure. SFV was intracoronarily delivered 2 weeks after induction of myocardial infarction in the rat model for heart failure. Duration of SFV expression was determined, and tissue distribution was studied by histochemical, biochemical, and reverse transcriptase-polymerase chain reaction (RT-PCR) analyses. Expression of SFV-mediated transfection in the heart reached its maximum after 48-72 h and subsided within a week. Intracoronary administration of SFV efficiently transfected the non-infarcted cardiac wall, resulting in high levels of beta-galactosidase (beta-gal) activity (1337 +/- 537 IU/mg) and lacZ RNA in the hearts of all rats, whereas brain, kidney, liver, lung, spleen, and testis were lacZ negative. In conclusion, intracoronarily delivered SFV has a favourable distribution pattern, showing expression of the transgene restricted to the heart.
J Mol Cell Cardiol 2004 Jul
PMID:Semliki Forest virus is an efficient and selective vector for gene delivery in infarcted rat heart. 1524 44

Endothelial cells (ECs) in normal vessels are poorly transducible by retroviral vectors, which require cell division for gene transduction. Among retroviruses, lentiviruses have the unique ability to integrate their genome into the chromatin of nondividing cells. Here we show that multiply attenuated, self-inactivating, lentiviral vectors transduce both proliferating and growth-arrested human umbilical vein ECs (HUVECs), human coronary artery ECs (HCAECs), and human coronary artery smooth muscle cells (HCASMCs), with high efficacy. Lentiviral vectors containing the enhanced green fluorescence protein (EGFP) transgene driven by either the cytomegalovirus or the elongation factor-1alpha promoter, but not the phosphoglycerate kinase promoter, directed high-level EGFP expression in endothelial and smooth muscle cells. The endothelium-specific Tie2 promoter also directed transgene expression in ECs. Re-insertion of cis-acting sequences from pol of human immunodeficiency virus type 1 (HIV-1) into the vectors improved transgene expression. A lentiviral vector containing the vascular endothelial growth factor transgene promoted EC proliferation and sprouting in vitro. In vivo gene transfer was studied by lumenal infusion of vector containing solutions into rat carotid arteries. Lentivirus-mediated EGFP gene transfer was observed in approximately 5% of ECs. Lentiviral vectors containing the LacZ transgene achieved detectable beta-galactosidase activity in rat arteries, albeit at a lower level compared with adenoviral vectors. This difference was mainly due to the lower concentration of lentiviral vector preparations. Lentivirus-mediated gene transfer was associated with minimal neointimal hyperplasia and scant inflammatory cell infiltrates in the media and adventitia. These observations indicate that lentiviral vectors may be useful for genetic modifications of vascular cells in vitro and in vivo.
J Mol Cell Cardiol 2005 Feb
PMID:Multiply attenuated, self-inactivating lentiviral vectors efficiently transduce human coronary artery cells in vitro and rat arteries in vivo. 1569 40

We have tested the feasibility of using recombinant adeno-associated virus (rAAV) vectors as a tool for labeling bone marrow (BM) cells in vivo. We infected BM cells of donor FVB mice with rAAV vectors containing the lacZ gene for 2 h. We then injected the rAAV-infected cells to lethally irradiated-recipient FVB mice. Peripheral blood (PB), BM and spleen harvested at 4 weeks after BM transplant (BMT) demonstrated stable engraftment in beta-galactosidase (beta-gal) expression. In contrast, Dil-labeling displayed only a faint signal 4 weeks after BMT. To analyze the kinetics of BM cells, we injected vascular endothelial growth factor (VEGF), which promotes mobilization of BM cells. Administration of VEGF protein significantly increased the rAAV-mediated beta-gal expression in PB and BM of recipient mice. Moreover, when myocardial infarction was induced in BMT mice, the ischemic area exhibited significant beta-gal staining in rAAV-labeled BMT group. rAAV vectors programmed stable transduction in BM cells in vivo through rapid infection. rAAV appears to represent a useful vector for labeling BM cells ex vivo prior to BMT for analysis of cardiovascular therapeutic purposes.
J Mol Cell Cardiol 2005 May
PMID:Use of recombinant adeno-associated viral vectors as a tool for labeling bone marrow cells. 1585 May 73

Initial studies have suggested that transplantation of embryonic stem (ES) cells following myocardial infarction (MI) in animal models is beneficial; however, the mechanism of benefit is largely unknown. The present study investigated the fate of mouse ES cells transplanted post-MI to determine if the ES cells give rise to the range of major cell types present in the native myocardium. MI was produced by coronary artery ligation in C57BL/6 mice. Two different mouse ES cell lines, expressing eGFP and beta-galactosidase, respectively, were tested. Post-MI intramyocardial injection of 3 x 10(4) ES cells was compared to injection of media alone. Histochemistry and immunofluorescence were used to track the transplanted ES cells and identify the resulting cell types. Echocardiography assessed the cardiac size and function in a blinded fashion. Two weeks post-MI, engraftment of the transplanted ES cells was demonstrated by eGFP or beta-galactosidase-positive cells in the infarct region without evidence for tumor formation. Co-immunolabeling demonstrated that the transplanted ES cells had become cardiomyocytes, vascular smooth muscle, and endothelial cells. Echocardiographic analysis showed that ES cell transplantation resulted in reduced post-MI remodeling of the heart and improved cardiac function. In conclusion, transplanted mouse ES cells can regenerate infarcted myocardium in part by becoming cardiomyocytes, vascular smooth muscle, and endothelial cells that result in an improvement in cardiac structure and function. Therefore, ES cells hold promise for myocardial cellular therapy.
J Mol Cell Cardiol 2006 Jan
PMID:Transplantation of embryonic stem cells into the infarcted mouse heart: formation of multiple cell types. 1628 79

Our previous studies showed that homocysteine (Hcy) reduces endothelial progenitor cell (EPC) numbers and impairs functional activity. However, the mechanisms by which Hcy reduces EPCs numbers and activity remain to be determined. Recent studies have demonstrated that reduced EPCs numbers and activity was associated with EPCs senescence which involved telomerase activity. Therefore, we investigated whether Hcy accelerates the onset of EPCs senescence through telomerase inactivation, leading to cellular dysfunction. EPCs were isolated from peripheral blood and characterized. After ex vivo cultivation, EPCs became senescent as determined by acidic beta-galactosidase staining. Hcy dose-dependently accelerated the onset of EPCs senescence in culture. Moreover, Hcy decreased proliferation of EPCs as assessed by BrdU incorporation assay and colony-forming capacity. To get further insights into the underlying mechanisms of these effects induced by Hcy, we measured telomerase activity and determined the phosphorylation of Akt by using western blot. Hcy significantly diminished telomerase activity and Akt phosphorylation. Taken together, the results of the present study demonstrated that Hcy accelerated the onset of EPCs senescence, leading to cellular dysfunction. The effect of Hcy might be dependent on telomerase inactivation, and Akt dephosphorylation also appeared to play a major role. In addition, atorvastatin had a preventative effect against Hcy-induced EPCs senescence.
J Mol Cell Cardiol 2006 May
PMID:Homocysteine accelerates senescence and reduces proliferation of endothelial progenitor cells. 1660 Feb 90

The aim of this study was to examine whether short- and long-term gene transfer of Ca(2+) handling proteins restore left ventricular (LV) mechanoenergetics in aortic banding-induced failing hearts. Aortic-banded rats received recombinant adenoviruses carrying sarcoplasmic reticulum Ca(2+)-ATPase (SERCA2a) (Banding+SERCA), parvalbumin (Banding+Parv) or beta-galactosidase (Banding+betagal), or an adeno-associated virus carrying SERCA2a (Banding+AAV.SERCA) by a catheter-based technique. LV mechanoenergetic function was measured in cross-circulated hearts. "Banding", "Banding+betagal" and "Banding+saline" groups showed lower end-systolic pressure at 0.1 ml intraballoon water (ESP(0.1)), higher end-diastolic pressure at 0.1 ml intraballoon water (EDP(0.1)) and slower LV relaxation rate, compared with "Normal" and "Sham". However, "Banding+SERCA" and "Banding+Parv" showed high ESP(0.1), low EDP(0.1) and fast LV relaxation rate. In "Banding", "Banding+betagal" and "Banding+saline", slope of relation between cardiac oxygen consumption and systolic pressure-volume area, O(2) cost of total mechanical energy, was twice higher than normal value, whereas slope in "Baning+SERCA" and "Banding+Parv" was similar to normal value. Furthermore, O(2) cost of LV contractility in the 3 control banding groups was approximately 3 times higher than normal value, whereas O(2) cost of contractility in "Banding+SERCA", "Banding+AAV.SERCA" and "Banding+Parv" was as low as normal value. Thus, high O(2) costs of total mechanical energy and of LV contractility in failing hearts indicate energy wasting both in chemomechanical energy transduction and in calcium handling. Improved calcium handling by both short- and long-term overexpression of SERCA2a and parvalbumin transforms the inefficient energy utilization into a more efficient state. Therefore enhancement of calcium handling either by resequestration into the SR or by intracellular buffering improves not only mechanical but energetic function in failing hearts.
J Mol Cell Cardiol 2007 Apr
PMID:Restoration of mechanical and energetic function in failing aortic-banded rat hearts by gene transfer of calcium cycling proteins. 1730 Aug

There is an association between obesity and heart failure associated with LV dysfunction. Adiponectin is an adipocyte-derived hormone that is downregulated in obesity. Here, we examined the role of adiponectin in cardiac remodeling after myocardial infarction with loss- and gain-of-function genetic manipulations in an experimental model. Myocardial infarction was created in adiponectin-deficient (APN-KO) and wild-type (WT) mice by the permanent ligation of the left anterior descending (LAD) artery. For some experiments, adenoviral vectors expressing adiponectin or beta-galactosidase were delivered systemically. Cardiac structure and function were assessed by echocardiographic and Millar catheter measurements. Myocardial capillary density was assessed by staining with anti-CD31 antibody. Myocyte apoptotic activity was determined by TUNEL-staining. Myocardial interstitial fibrosis was evaluated by Masson's trichrome staining. APN-KO mice showed exacerbated left ventricular (LV) dilation, myocyte hypertrophy and contractile dysfunction compared with WT mice at 4 weeks after LAD ligation. Impaired LV function in APN-KO mice was coupled to myocyte hypertrophy, increased apoptotic activity and interstitial fibrosis in the remote zone, and reduced capillary density in the infarct border zone. No difference in infarct size was observed between WT and APN-KO mice. Administration of adenovirus-mediated adiponectin in WT mice resulted in decreased LV dilatation and improved LV function that was associated with increased capillary density in the infarct border zone and decreased myocyte hypertrophy, diminished myocardial apoptosis and decreased interstitial fibrosis in the remote zone. These data suggest that adiponectin protects against the development of systolic dysfunction after myocardial infarction through its abilities to suppress cardiac hypertrophy and interstitial fibrosis, and protect against myocyte and capillary loss.
J Mol Cell Cardiol 2007 Jun
PMID:Adiponectin protects against the development of systolic dysfunction following myocardial infarction. 1749 64


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