Related Experiment Videos
Atherosclerosis and acetaldehyde metabolism in blood
H Ohlin1, L Brattström, B Israelsson
1Department of Medicine, University Hospital, Lund, Sweden.
Insights
Patients with arterial stenosis show faster acetaldehyde elimination in blood, linked to reduced protein binding, not aldehyde dehydrogenase activity. This suggests protein modification in atherosclerotic disease.
Area of Science:
- Biochemistry
- Cardiovascular Science
- Toxicology
Background:
- Acetaldehyde metabolism is crucial for understanding alcohol-related health issues.
- Aldehyde dehydrogenase (ALDH) is a key enzyme in acetaldehyde detoxification.
- Atherosclerotic diseases affect major arteries and may influence metabolic processes.
Purpose of the Study:
- To investigate acetaldehyde elimination and aldehyde dehydrogenase (ALDH) activity in patients with symptomatic arterial stenosis.
- To explore the relationship between acetaldehyde metabolism and protein binding in atherosclerotic patients.
Main Methods:
- Studied acetaldehyde elimination in blood homogenates and ALDH activity in 64 patients with arterial stenosis and 38 controls.
- Analyzed [14C]acetaldehyde binding to plasma proteins, hemoglobin, and erythrocyte membranes in 10 patients and 12 controls.
- Measured acetaldehyde half-life (T1/2) and correlated it with protein binding.
Main Results:
- Patients exhibited significantly enhanced acetaldehyde elimination (T1/2 = 103 min) compared to controls (T1/2 = 198 min).
- No correlation was found between ALDH activity and acetaldehyde elimination rate.
- A significant correlation (p=0.74) was observed between unstable [14C]acetaldehyde binding to plasma proteins and faster acetaldehyde elimination.
- Acetaldehyde binding to hemoglobin and erythrocyte membranes did not differ between groups.
Conclusions:
- Patients with angiopathy demonstrate enhanced blood acetaldehyde elimination, associated with reduced binding to plasma proteins.
- The findings suggest potential modifications of protein amino groups in atherosclerotic disease, impacting acetaldehyde binding.
Abstract:
Acetaldehyde elimination in blood homogenates and erythrocyte aldehyde dehydrogenase (ALDH) activity were studied in 64 patients operated before the age of 60 years because of symptomatic stenosis of aorta, iliac, or carotid arteries and in 38 healthy controls. The disappearance of acetaldehyde in blood homogenates was biphasic. Patients showed an enhanced elimination of acetaldehyde during the second phase (30-60 min), as compared to controls (T1/2 of acetaldehyde was 103 +/- 47 and 198 +/- 93 min, respectively, P less than 0.001). No correlation was found between ALDH activity and acetaldehyde elimination rate. Acetaldehyde elimination in blood homogenates and [14C]acetaldehyde binding to plasma proteins, hemoglobin, and erythrocyte membranes were studied in 10 patients with atherosclerotic disease and in 12 healthy controls. There was a significant correlation between unstable binding of [14C]acetaldehyde to plasma proteins and the half-life of acetaldehyde in the elimination test (p = 0.74, P less than 0.005). Fractionation of plasma proteins after incubation with [14C]acetaldehyde revealed no difference between patients and controls in the distribution of radioactivity. The binding of [14C]acetaldehyde to hemoglobin or erythrocyte membranes did not differ between patients and controls. These results indicate that patients with angiopathy and an enhanced acetaldehyde elimination in blood have reduced binding of acetaldehyde to plasma proteins. As unstable binding of acetaldehyde to proteins is known to involve free amino groups of amino acid residues, modification of these residues in atherosclerotic disease is conceivable.