Spectrophotometric assay for the condensing enzyme activity of the microsomal fatty acid chain elongation system

Nagi, Mahmoud N.; Cook, Lynda; Suneja, Sanoj K.; Osei, Peter; Cinti, Dominick L.

doi:10.1016/0003-2697(89)90124-3

Cited by 11 publications

(7 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The substrate-dependent rate was determined by subtracting the NADPH oxidation rate from the rate after adding malonylCoA. Glycerol-3-phosphate acyltransferase GPAT activity in microsomes was determined according to Yamada 40 . In brief, the assay mixture contained 15 nmol palmitoyl-CoA or palmitoleoyl-CoA, 100 nmol 2-14 C malonyl-CoA 20 nCi , 12 nmol bovine serum albumin, 0.5 μmol KCN, 250 μg of microsomal protein and 100 mM Tris-HCl pH 7.4 in a total volume of 0.5 mL.…”

Section: Enzyme Assaysmentioning

confidence: 99%

Altered Fatty Acid Profile in the Liver and Serum of Stroke-Prone Spontaneously Hypertensive Rats: Reduced Proportion of cis-Vaccenic Acid

et al. 2013

View full text Add to dashboard Cite

Section: Enzyme Assaysmentioning

confidence: 99%

Altered Fatty Acid Profile in the Liver and Serum of Stroke-Prone Spontaneously Hypertensive Rats: Reduced Proportion of cis-Vaccenic Acid

et al. 2013

View full text Add to dashboard Cite

“…The assay for microsomal condensation of palmitoylCoA was performed spectrophotometrically by measuring the formation of β-ketopalmitoyl-CoA -bovine serum albumin complex (10). Briefly, the assay was performed by recording the changes in absorbance between 303 and 350 nm at 37°C.…”

Section: Enzyme Assaysmentioning

confidence: 99%

Effects of Pioglitazone on Stearoyl-CoA Desaturase in Obese Zucker fa/fa Rats

et al. 2007

View full text Add to dashboard Cite

Abstract. The effects of a peroxisome proliferator activated receptor γ (PPARγ) agonist on hepatic stearoyl-CoA desaturase (SCD) in insulin-resistant and obese Zucker fa / fa rats were studied. The administration of pioglitazone, a PPARγ agonist, to Zucker obese rats greatly improved their insulin sensitivity. The treatment of Zucker obese rats with pioglitazone did not affect the index of fatty acid desaturation of either serum or liver. Hepatic SCD activity and the mRNA level of SCD1 were not changed by treatment of the rats with pioglitazone. The activity of palmitoly-CoA chain elongase, which is involved in the biosynthesis of oleic acid in concert with SCD, was not significantly altered when Zucker obese rats received pioglitazone. Although neither the activity nor mRNA expression of acyl-CoA oxidase was changed by treatment of Zucker obese rats with pioglitazone, the mRNA expressions of both sterol regulatory elementbinding protein-1c and acetyl-CoA carboxylase sensitively responded to the challenge by pioglitazone. These results suggest that the insulin sensitivity of insulin-resistant and obese Zucker fa / fa rats is improved by pioglitazone independently of SCD activity.

show abstract

“…The method II radiochemical assay for fatty acyl-CoA elongation was identical except that the solvent in the pooled petroleum ether extracts was allowed to evaporate to dryness at room temperature before the samples were taken for liquid scintillation counting. Activity of the condensing enzyme of the fatty acyl-CoA elongation system was measured spectrophotometrically at 37 mC as described previously [29], in 1 ml of buffer containing 0.1 M Tris\HCl (pH 7.4), bovine albumin (2.6 mg\ml), 40 µM palmitoyl-CoA and 0.25 mg of microsomal protein. A baseline was recorded in a split-beam spectrophotometer by scanning from 400-290 nm against an identical reference cuvette.…”

Section: Enzyme Assaysmentioning

confidence: 99%

“…A baseline was recorded in a split-beam spectrophotometer by scanning from 400-290 nm against an identical reference cuvette. The reaction was then initiated by addition of 60 µM malonyl-CoA to the sample cuvette, and the relative change in absorbance at 303 nm (due to the formation of an enolate-albumin compex [29]) was followed. Any change in absorbance at 350 nm was subtracted from that observed at 303 nm.…”

Section: Enzyme Assaysmentioning

confidence: 99%

Malonyl-CoA metabolism in cardiac myocytes

HAMILTON

Saggerson

2000

Biochem. J.

View full text Add to dashboard Cite

(1) Malonyl-CoA is thought to play a signalling role in fuel-selection in cardiac muscle, but the rate at which the concentration of this potential signal can be changed has not previously been investigated. (2) Rapid changes in cellular malonyl-CoA could be observed when rat cardiac myocytes were incubated in glucose-free medium followed by re-addition of 5 mM glucose, or when cells were transferred from a medium containing glucose to a glucose-free medium. On addition of glucose, malonyl-CoA increased by 62% to a new steady-state level, at a rate of at least 0.4 nmol/g dry wt. per min. The half-time of this change was less than 3 min. After removal of glucose the malonyl-CoA content was estimated to decline by 0.43-0.55 nmol/g dry wt. per min. (3) Malonyl-CoA decarboxylase (MDC) is a possible route for disposal of malonyl-CoA. No evidence was obtained for a cytosolic activity of MDC in rat heart where most of the activity was found in the mitochondrial fraction. MDC in the mitochondrial matrix was not accessible to extramitochondrial malonyl-CoA. However, approx. 16% of the MDC activity in mitochondria was overt, in a manner that could not be explained by mitochondrial leakage. It is suggested that this, as yet uncharacterized, overt MDC activity could provide a route for disposal of cytosolic malonyl-CoA in the heart. (4) No activity of the condensing enzyme for the fatty acid elongation system could be detected in any heart subcellular fraction using two assay systems. A previous suggestion [Awan and Saggerson (1993) Biochem. J. 295, 61-66] that this could provide a route for disposal of cytosolic malonyl-CoA in heart should therefore be abandoned.

show abstract

Spectrophotometric assay for the condensing enzyme activity of the microsomal fatty acid chain elongation system

Cited by 11 publications

References 33 publications

Altered Fatty Acid Profile in the Liver and Serum of Stroke-Prone Spontaneously Hypertensive Rats: Reduced Proportion of cis-Vaccenic Acid

Altered Fatty Acid Profile in the Liver and Serum of Stroke-Prone Spontaneously Hypertensive Rats: Reduced Proportion of cis-Vaccenic Acid

Effects of Pioglitazone on Stearoyl-CoA Desaturase in Obese Zucker fa/fa Rats

Malonyl-CoA metabolism in cardiac myocytes

Contact Info

Product

Resources

About