Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The small GTPase rac1 controls actin redistribution to membrane ruffles in fibroblasts and other cell types, as well as the activation of the NADPH oxidase in phagocytes. We explored the possibility that these two processes could be related. We used a replication-deficient adenoviral vector to overexpress the constitutively active form of rac1, racV12, in human and mouse aortic endothelial cells. We show here that, in addition to membrane ruffle formation, racV12 induced an increase in the total amount of F-actin within endothelial cells. Concurrently, racV12-overexpressing cells produced significantly higher amounts of free radicals, as detected by the fluorescent probe 5-(and-6)-chloromethyl-2',7'-dichloro-dihydrofluorescein diacetate, than cells infected with a control virus encoding the bacterial beta-galactosidase (Ad-betaGal). To assess the specific role of superoxide in racV12-induced actin reorganization, we co-expressed the human enzyme Cu,Zn-superoxide dismutase (SOD), by means of another adenoviral vector construct. Overexpressed SOD reduced the concentration of superoxide detected in Ad-racV12-transfected cells and reversed the effects of Ad-racV12 on the content of filamentous actin. MnTMPyP, an SOD mimetic, as well as the antioxidant N-acetyl cysteine, had similar effects, in that they reduced not only the free radicals production, but also ruffle formation and the concentration of F-actin within racV12-overexpressing endothelial cells. Our data support the hypothesis that superoxide is one of the important mediators acting downstream of rac1 on the pathway of actin cytoskeleton remodeling in endothelial cells.
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PMID:The actin cytoskeleton reorganization induced by Rac1 requires the production of superoxide. 1122 30

Although hypertension is a major risk factor for atherosclerosis, its underlying mechanisms remain to be delineated. We have recently reported that both endothelin-1 (ET-1) and vascular cellular adhesion molecule-1 (VCAM-1) levels, key early markers of atherosclerosis, are significantly elevated in carotid arteries of deoxycorticosterone acetate (DOCA)-salt hypertensive rats, a model known for its suppressed plasma renin levels. This study tested the hypothesis that ET-1 augments arterial VCAM-1 expression through NADPH oxidase-derived superoxide (O2-). Carotid arteries of DOCA-salt or sham-operated rats were transduced ex vivo with extracellular superoxide dismutase (EC-SOD), dominant negative HA-tagged N17Rac1 that inhibits Rac1, the small GTPase component of NADPH oxidase, or beta-galactosidase (beta-gal) reporter gene (5x10(10) plaque formation units [pfu]/mL), and the effect of transgene expression on O2- and VCAM-1 levels was assayed 24 hours afterward. The arterial activity of NADPH oxidase but not xanthine oxidase was significantly higher in DOCA-salt than in sham rats, which was abolished by the selective ETA receptor antagonist ABT-627 (3x10(-8) mol/L), NADPH oxidase inhibitor apocynin (10(-4) mol/L), or dominant negative Rac1 gene transfer. The levels of O2- and VCAM-1 were significantly increased in arteries of DOCA-salt rats, an effect that was ameliorated after EC-SOD or dominant negative Rac1 but not beta-gal reporter gene transfer. ABT-627 and apocynin also significantly reduced elevated VCAM-1 levels in ET-1-treated arteries of normal rats and arteries of DOCA-salt rats. The results of this study indicate that ET-1 stimulates arterial VCAM-1 expression by producing O2- from an ETA receptor/NADPH oxidase pathway in low-renin mineralocorticoid hypertension.
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PMID:Endothelin-1 stimulates arterial VCAM-1 expression via NADPH oxidase-derived superoxide in mineralocorticoid hypertension. 1451 26

An efficient route for delivering specific proteins and peptides into neurons could greatly accelerate the development of therapies for various diseases, especially those involving intracellular defects such as Parkinson disease. Here we report the novel use of polybutylcyanoacrylate nanoparticles for delivery of intact, functional proteins into neurons and neuronal cell lines. Uptake of these particles is primarily dependent on endocytosis via the low density lipoprotein receptor. The nanoparticles are rapidly turned over and display minimal toxicity to cultured neurons. Delivery of three different functional cargo proteins is demonstrated. When primary neuronal cultures are treated with recombinant Escherichia coli beta-galactosidase as nanoparticle cargo, persistent enzyme activity is measured beyond the period of nanoparticle degradation. Delivery of the small GTPase rhoG induces neurite outgrowth and differentiation in PC12 cells. Finally, a monoclonal antibody directed against synuclein is capable of interacting with endogenous alpha-synuclein in cultured neurons following delivery via nanoparticles. Polybutylcyanoacrylate nanoparticles are thus useful for intracellular protein delivery in vitro and have potential as carriers of therapeutic proteins for treatment of neuronal disorders in vivo.
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PMID:Functional protein delivery into neurons using polymeric nanoparticles. 1912 99