Manipulation of lipid composition of rat heart myocytes aged in culture and its effect on alpha1-adrenoceptor stimulation.
The fatty acid composition of the phosphoinositides was evaluated in cultured neonatal rat cardiomyocytes during the aging-like process in vitro, comparing data obtained from control and gamma-linolenic acid supplemented cardiomyocytes. The response to alpha1 stimulation was evaluated in both control and supplemented cells to verify the relationship between the alterations of the phosphoinositide fatty acid composition concomitant to culture aging and the cell response to exogenous stimuli. Arachidonate level decreased as a function of age in all the phosphoinositides, which appeared to be more saturated as cells aged in culture. Inositol phosphate production in response to alpha1 stimulation decreased as cells aged in culture. Supplementation of culture medium with gamma-linolenic acid caused significant modifications in the fatty acid pattern of the phosphoinositides, which appeared less saturated than the corresponding fractions isolated from unsupplemented cells during the aging-like process. The modifications induced by the supplementation in the phosphoinositide fatty acid composition prevented the age-related reduction of inositol phosphate production upon stimulation. These results clearly indicate a major role for the lipid composition in determining the response to alpha1 stimulation, suggesting a nutritional approach to overcome some of the impairments of molecular events related to the process of aging.
Bordoni
A
A
Department of Biochemistry G. Moruzzi, University of Bologna, Italy.
Lorenzini
A
A
Horrobin
D F
DF
Biagi
P L
PL
Hrelia
S
S
D000818:Animals; D016718:Arachidonic Acid / Q000032:analysis; D002478:Cells, Cultured; D005227:Fatty Acids / Q000032:analysis; D005231:Fatty Acids, Unsaturated / Q000032:analysis; D050356:Lipid Metabolism; D008055:Lipids / Q000032:analysis; D009206:Myocardium / Q000378:metabolism*; D019269:Phosphatidylinositol 4,5-Diphosphate / Q000032:analysis; D018129:Phosphatidylinositol Phosphates / Q000032:analysis; D010716:Phosphatidylinositols / Q000032:analysis / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D018340:Receptors, Adrenergic, alpha-1 / Q000502:physiology*; D013997:Time Factors; D017965:gamma-Linolenic Acid / Q000032:analysis / Q000494:pharmacology
D005227:Fatty Acids; D005231:Fatty Acids, Unsaturated; D008055:Lipids; D019269:Phosphatidylinositol 4,5-Diphosphate; D018129:Phosphatidylinositol Phosphates; D010716:Phosphatidylinositols; D018340:Receptors, Adrenergic, alpha-1; D016718:Arachidonic Acid; D017965:gamma-Linolenic Acid