Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.3.3.1 (citrate synthase)
 4,488 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of chronic left ventricular pressure overload on the activities of mitochondrial respiratory chain enzymes was investigated in myocardial biopsies from the left ventricular apex of 13 patients undergoing aortic valve replacement for aortic valve stenosis. Transvalvular pressure gradients measured by left-sided heart catheterization ranged from 52 to 100 mmHg. The specific activity of mitochondrial respiratory chain enzyme complexes I+III (antimycin A sensitive NADH cytochrome c oxidoreductase) and the myocardial concentrations of coenzyme Q10 (CoQ10) increased significantly (P < 0.05) with increasing aortic valve pressure gradient. In contrast, the specific activities of complex IV (cytochrome c oxidase), succinate dehydrogenase, and citrate synthase, a mitochondrial matrix enzyme, showed no significant correlation with the pressure gradient. Since CoQ10 is the rate-limiting compound of the activity of complexes I+III but not of cytochrome c oxidase, succinate dehydrogenase, or citrate synthase, these data suggest that the increase in the activity of complexes I+III is due to the increase in CoQ10 content.
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PMID:Positive correlation between aortic valve pressure gradient and mitochondrial respiratory chain capacity in hypertrophied human left ventricle. 145 Jun 14

Mitochondrial respiratory chain enzyme activities were measured in biopsies of left ventricular myocardium from 25 adults in 3 groups: cardiac transplant recipients with atherosclerotic coronary artery disease (CAD), transplant recipients with idiopathic dilated cardiomyopathy (IDC), and patients with compensatory left ventricular hypertrophy due to aortic valve stenosis (AS). Specific activities of complexes I + III and II + III were 21 +/- 12 and 58 +/- 21 nmol/min/mg of noncollagen protein, respectively, in CAD, and 56 +/- 21 and 96 +/- 57 nmol/min/mg, respectively, in IDC (p < 0.004 and < 0.03, respectively). Specimens from patients with AS had enzyme activities that were intermediate between those from patients with CAD and IDC. Myocardium of patients with transvalvular pressure gradients between 50 and 79 mm Hg showed low activities of complexes I + III and II + III (17 +/- 5 and 62 +/- 17 nmol/min/mg of noncollagen protein, respectively), whereas those with higher pressure gradients between 80 and 100 mm Hg had enzyme activities of complexes I + III and II + III equal to those in IDC (37 +/- 11 and 73 +/- 18 nmol/min/mg, respectively). The same results were obtained when enzyme activities were normalized for the activity of the mitochondrial matrix enzyme citrate synthase. The data suggest that a compensatory metabolic adaptation of the mitochondrial respiratory chain enzymes occurs in both AS and IDC. A reduction in enzyme activities that is observed in heart failure due to CAD and that may explain the contractile dysfunction in these patients cannot be confirmed in IDC. In IDC, the enzyme activities are sustained until very late in the disease.
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PMID:Myocardial respiratory chain enzyme activities in idiopathic dilated cardiomyopathy, and comparison with those in atherosclerotic coronary artery disease and valvular aortic stenosis. 839 43

We report the first documented case of endocarditis associated with Bartonella clarridgeiae in any species. B. clarridgeiae was identified as a possible etiological agent of human cat scratch disease. Infective vegetative valvular aortic endocarditis was diagnosed in a 2.5-year-old male neutered boxer. Historically, the dog had been diagnosed with a systolic murmur at 16 months of age and underwent balloon valvuloplasty for severe valvular aortic stenosis. Six months later, the dog was brought to a veterinary hospital with an acute third-degree atrioventricular block and was diagnosed with infective endocarditis. The dog died of cardiopulmonary arrest prior to pacemaker implantation. Necropsy confirmed severe aortic vegetative endocarditis. Blood culture grew a fastidious, gram-negative organism 8 days after being plated. Phenotypic and genotypic characterization of the isolate, including partial sequencing of the citrate synthase (gltA) and 16S rRNA genes indicated that this organism was B. clarridgeiae. DNA extraction from the deformed aortic valve and the healthy pulmonic valve revealed the presence of B. clarridgeiae DNA only from the diseased valve. No Borrelia burgdorferi or Ehrlichia sp. DNA could be identified. Using indirect immunofluorescence tests, the dog was seropositive for B. clarridgeiae and had antibodies against Ehrlichia phagocytophila but not against Ehrlichia canis, Ehrlichia ewingii, B. burgdorferi, or Coxiella burnetii.
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PMID:Aortic valve endocarditis in a dog due to Bartonella clarridgeiae. 1157 71