Altered phosphatidylinositol breakdown after K-elastin stimulation in PMNLs of elderly.
The degradation of elastic fibres during atherosclerotic plaque formation in arterial wall is a well known process. The liberated elastin peptides such as K-elastin possess various biological activities: They are chemotactic for monocytes and fibroblasts, stimulate the oxidative burst and the intracellular free Ca2+ mobilisation through the phosphatidylinositol (PIP2) breakdown in PMNLs. It was found that the PIP2 breakdown induced by K-elastin is a pertussis toxin sensitive process in PMNLs of young subjects. In the case of the elderly, the K-elastin-induced oxidative burst, intracellular free Ca2+ elevation was less than in young, and could not be inhibited by pertussis toxin. Studying the K-elastin-induced inositol phosphate (IP) formation in PMNLs of elderly a disturbed PIP2 breakdown was found. K-elastin stimulated the IP formation at a very low level in PMNLs of elderly. This alteration of the second messenger formation (e.g. IP3 and Ca2+) after KE stimulation, might be the consequence of their originally elevated levels in resting PMNLs of elderly.
Varga
Z
Z
First Department of Medicine, University of Medical School, Debrecen, Hungary.
Jacob
M P
MP
Csongor
J
J
Robert
L
L
Leövey
A
A
Fülöp
T
T
D000367:Age Factors; D000368:Aged; D004549:Elastin / Q000502:physiology*; D006801:Humans; D009504:Neutrophils / Q000187:drug effects / Q000378:metabolism*; D019269:Phosphatidylinositol 4,5-Diphosphate; D010716:Phosphatidylinositols / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*
D019269:Phosphatidylinositol 4,5-Diphosphate; D010716:Phosphatidylinositols; D004549:Elastin