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Effect of substrate composition and concentration on aortic cholesterol ester hydrolase activity
Enzyme
|January 1, 1978
Summary
Pig aorta cholesterol ester hydrolase activity varies by substrate. The enzyme preferentially hydrolyzes cholesteryl linoleate and linolenate, impacting arterial cholesterol ester accumulation.
Area of Science:
- Biochemistry
- Cardiovascular Science
- Enzymology
Background:
- Cholesterol ester accumulation in arteries contributes to atherosclerosis.
- Cholesterol ester hydrolase (CEH) plays a role in regulating arterial cholesterol levels.
Purpose of the Study:
- To investigate the substrate specificity of cholesterol ester hydrolase activity in pig aorta.
- To understand how different cholesterol ester substrates are hydrolyzed by the enzyme.
Main Methods:
- Assessing enzyme specific activity under optimal conditions.
- Measuring the hydrolysis rates of various cholesterol esters, including linoleate, linolenate, palmitate, stearate, and oleate.
Main Results:
- The enzyme specific activity followed the order: cholesteryl linoleate ≥ linolenate > palmitate ≥ stearate > oleate.
- Significant differences in hydrolysis rates were observed among the tested cholesterol esters.
Conclusions:
- Pig aorta cholesterol ester hydrolase exhibits distinct substrate preferences.
- These findings provide insights into the enzymatic regulation of cholesterol ester deposition in arterial tissue.
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