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)

A non-contracting scar following myocardial infarction can adversely affect ventricular topography and hemodynamic function. Gene transfer has the potential to prevent or alter such pathophysiological processes. Normal myocardium is a proven target for delivery of DNA or viral vectors but the potential for gene therapy in ischemic myocardium has not been evaluated. In an initial series of experiments, we determined whether the direct injection of reporter genes into hearts subjected to coronary artery occlusion followed by reperfusion could result in gene expression comparable to the levels observed in non-occluded normal hearts. Anesthetized rats were subjected to 15 min or 60 min of proximal coronary occlusion or sham operation. Luciferase gene under the control of the Rous sarcoma virus promoter was injected directly into the anterior left wall. At 1 week, high expression of luciferase was observed in both the ischemic/reperfused and non-ischemic tissue. Thus DNA transfer by direct injection is possible after ischemic injury and uptake and expression are not impaired. In a second series of experiments, myocardial infarcts in dogs were injected with a beta-galactosidase expressing retroviral vector. LNPOZ. Six to 11 days later frozen sections revealed macroscopically visible expression of beta-galactosidase activity. Not only can foreign genes be taken up by direct injection of DNA or retroviruses into ischemic/reperfused myocardium but they can be transcribed and the protein synthetic machinery of the injured cells can produce recombinant polypeptides that retain enzymatic activity. These results open the way for the investigation of gene therapy in models of ischemia.
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PMID:Ischemic/reperfused myocardium can express recombinant protein following direct DNA or retroviral injection. 874 21

An efficient gene delivery system is a prerequisite for myocardial gene therapy. Among the various procedures studied so far, catheter-based percutaneous gene delivery to the myocardium through the coronary vessels seems the most relevant to routine clinical practice; however, the optimal conditions remain to be determined. We selectively infused adenoviral vectors encoding luciferase (1 x 10(9) PFU) or beta-galactosidase (1 x 10(10) PFU) into coronary arteries of adult rabbits in various experimental conditions. Coronary artery occlusion for 30 sec, during and after adenovirus delivery, was required to observe luciferase activity in the target area of the circumflex artery (4.0 +/- 1.0 x 10(5) vs. 1.1 +/- 0.2 x 10(4) RLU/mg with and without coronary occlusion, respectively, p < 0.01, and 1.0 +/- 0.1 x 10(3) RLU/mg using nonselective infusion). When adenoviruses were delivered using high-pressure infusion (82 +/- 12 vs. 415 +/- 25 mmHg before and during infusion, respectively, p < 0.01), luciferase activity increased to 8.5 +/- 2.5 x 10(5) RLU/mg (p < 0.05 vs coronary occlusion alone). Coronary venous sinus occlusion with saline buffer retroinfusion starting before and during anterograde adenovirus delivery resulted in a further 4.7-fold increase in luciferase activity (4.4 +/- 0.8 x 10(6) RLU/mg, p < 0.01) with 5-25% blue-stained myocytes in the target area, compared with 0-5% with the other procedures. Histamine or VEGF-A(165) pretreatment, used to increase vascular permeability, slightly increased gene transfer efficiency (8.5 +/- 2.0 x 10(5) and 9.0 +/- 2.5 x 10(5) RLU/mg respectively, p < 0.05 vs. coronary occlusion alone). We conclude that catheter-mediated adenoviral gene transfer to cardiac myocytes through coronary vessels can be a very efficient procedure for myocardial gene therapy, particularly when the vector residence time and perfusion pressure in the vessels are increased.
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PMID:How to optimize in vivo gene transfer to cardiac myocytes: mechanical or pharmacological procedures? 1153 64

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.
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PMID:G-CSF treatment increases side population cell infiltration after myocardial infarction in mice. 1513 66

The purpose of this study was to examine the influence of adenovirus-carried VEGF165 transgene at 5 x 10(10) pfu (Ad-VEGF) on vascular formation, cardiac geometry and ventricular function in infarcted hearts of the rat and to explore the mechanism of Ad-VEGF-mediated actions on ventricular function by quantitative proteomic analysis. Seven days after coronary occlusion, intramyocardial injection with normal saline (vehicle control), adenovirus-carried beta-galactosidase gene (Ad-LacZ, vector control) or Ad-VEGF to infarcted hearts was conducted. Seven days after intramyocardial injection, ventricular function, cardiac morphology and vascular density were assessed after echocardiographic analysis and immunohistological staining. One dimensional gel electrophoresis coupled with stable isotope dimethyl labeling and LC/MS/MS was used to quantify the abundance ratio of each protein pair in Ad-VEGF- and Ad-LacZ-treated hearts. Our data indicated that both Ad-VEGF and Ad-LacZ increased arteriolar densities. However, the former increased arterial densities but the latter did not. Compared with the vehicle control, Ad-LacZ reversed occlusion-induced wall thinning and functional impairment but Ad-VEGF did not. Quantitative proteomic analysis showed increased ratios of plasma proteins (such as albumin) and oxygen carriers (such as myoglobin) by Ad-VEGF and decreased ratios of proteins involved in glycolysis, calcium homeostasis and lipolysis by Ad-VEGF. Taken together, our functional, morphological and proteomic data suggest that intramuscular delivery of Ad-LacZ at higher doses may improve ventricular function and wall thinning with arteriolar formation. Excessive amounts of VEGF by Ad-VEGF may offset Ad-LacZ-induced improvement in ventricular functions by interfering with calcium homeostasis and lipolysis in infarcted hearts.
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PMID:Enhancement of vascular formation but not improvement of ventricular function of infarcted rat hearts by a high dose of adenovirus-carried VEGF transgene. 2035 29