Consumption of virgin olive oil influences membrane lipid composition and regulates intracellular signaling in elderly adults with type 2 diabetes mellitus.
We aimed to define changes in membrane fatty acids and signaling proteins induced by virgin olive oil (VOO) consumption in elderly persons with type 2 diabetes (n = 16) compared to a control group (n = 28). The fatty acid composition was determined by gas chromatography and G-protein subunits and protein kinase C alpha (PKCalpha) by immunoblotting. VOO consumption increased the monounsaturated fatty acid content in phospholipids and cholesterol esters in both groups. In contrast, saturated fatty acids were decreased only in phospholipids. The levels of Galphao, Gbeta, and PKCalpha were significantly lower in diabetics than in controls. However, whereas VOO consumption reduced Galphas, Gbeta, and PKCalpha in both groups, reduction in Galphai was observed only in diabetics. These results indicate that long-term VOO consumption modifies the fatty acid composition of plasma membrane, which influences the association of G proteins and PKCalpha with the lipid bilayer. These combined effects probably account for the positive effects of VOO on glycemic homeostasis.
Perona
Javier S
JS
Nutrition and Lipid Metabolism, Instituto de la Grasa (CSIC), Av Padre García Tejero, 4, 41012 Sevilla, Spain.
Vögler
Oliver
O
Sánchez-Domínguez
Jose M
JM
Montero
Emilio
E
Escribá
Pablo V
PV
Ruiz-Gutierrez
Valentina
V
D000368:Aged; D000369:Aged, 80 and over; D002788:Cholesterol Esters / Q000032:analysis; D002849:Chromatography, Gas; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism* / Q000503:physiopathology; D004042:Dietary Fats, Unsaturated / Q000008:administration & dosage*; D004910:Erythrocyte Membrane / Q000737:chemistry; D005227:Fatty Acids / Q000032:analysis; D005229:Fatty Acids, Monounsaturated / Q000032:analysis; D005260:Female; D044385:GTP-Binding Protein alpha Subunits / Q000032:analysis; D044387:GTP-Binding Protein beta Subunits / Q000032:analysis; D019204:GTP-Binding Proteins / Q000032:analysis; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000032:analysis*; D008051:Lipid Bilayers / Q000032:analysis; D008297:Male; D008563:Membrane Lipids / Q000032:analysis*; D000069463:Olive Oil; D010743:Phospholipids / Q000032:analysis; D010938:Plant Oils / Q000008:administration & dosage*; D051571:Protein Kinase C-alpha / Q000032:analysis; D015398:Signal Transduction / Q000502:physiology
D002788:Cholesterol Esters; D004042:Dietary Fats, Unsaturated; D005227:Fatty Acids; D005229:Fatty Acids, Monounsaturated; D044385:GTP-Binding Protein alpha Subunits; D044387:GTP-Binding Protein beta Subunits; D047908:Intracellular Signaling Peptides and Proteins; D008051:Lipid Bilayers; D008563:Membrane Lipids; D000069463:Olive Oil; D010743:Phospholipids; D010938:Plant Oils; D051571:Protein Kinase C-alpha; D019204:GTP-Binding Proteins