Membrane fluidity, membrane lipid pattern, and cytosolic Ca2+ content in platelets from a group of type II diabetic patients with macrovascular complications.
OBJECTIVE
To evaluate platelet membrane fluidity and some platelet metabolic parameters in type II diabetic patients with macrovascular complications.


METHODS
In a group of 21 type II diabetic patients with macrovascular complications, we evaluated platelet membrane fluidity [marking intact resting platelets with the fluorescent probe 1,4-(trimethylamino)-phenyl-4-phenylhexatriene (TMA-DPH)], platelet membrane lipid pattern (cholesterol:phospholipid [C:PL] ratio and individual phospholipids), and platelet cytosolic Ca2+ content (marking intact resting platelets with the fluorescent probe Fura 2AM).


RESULTS
Platelet membrane fluidity is decreased in type II diabetic patients with macrovascular complications compared with normal subjects (P < 0.001). Platelet membrane C:PL ratio and cytosolic Ca2+ content do not discriminate normal subjects from diabetic patients, and for individual phospholipids, only phosphatidylethanolamine is decreased in diabetic patients compared with control subjects (P = 0.051). In normal subjects, the polarization degree of TMA-DPH is related to phosphatidylserine (P < 0.05) and phosphatidylcholine (P < 0.05), and in diabetic patients the polarization degree of TMA-DPH is related to C:PL ratio (P < 0.05) and sphyngomyelin (P < 0.05).


CONCLUSIONS
In type II diabetic patients with macrovascular complications, we observed an abnormality of platelet membrane fluidity, which may contribute to platelet functional alteration present in this clinical condition.
Caimi
G
G
Institute of Internal Medicine and Cardiovascular Disease, University of Palermo, Italy.
Lo Presti
R
R
Montana
M
M
Canino
B
B
Ventimiglia
G
G
Romano
A
A
Catania
A
A
Sarno
A
A
D000368:Aged; D001792:Blood Platelets / Q000378:metabolism*; D002118:Calcium / Q000097:blood*; D003600:Cytosol / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D003925:Diabetic Angiopathies / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D008560:Membrane Fluidity / Q000502:physiology*; D008563:Membrane Lipids / Q000378:metabolism*; D008875:Middle Aged; D013050:Spectrometry, Fluorescence
D008563:Membrane Lipids; D002118:Calcium