The protective effect of the Mediterranean diet on endothelial resistance to GLP-1 in type 2 diabetes: a preliminary report

Cardiovasc Diabetol. 2014 Nov 19;13:140. doi: 10.1186/s12933-014-0140-9.

Abstract

Background: In type 2 diabetes, acute hyperglycemia worsens endothelial function and inflammation,while resistance to GLP-1 action occurs. All these phenomena seem to be related to the generation of oxidative stress. A Mediterranean diet, supplemented with olive oil, increases plasma antioxidant capacity, suggesting that its implementation can have a favorable effect on the aforementioned phenomena. In the present study, we test the hypothesis that a Mediterranean diet using olive oil can counteract the effects of acute hyperglycemia and can improve the resistance of the endothelium to GLP-1 action.

Methods: Two groups of type 2 diabetic patients, each consisting of twelve subjects, participated in a randomized trial for three months, following a Mediterranean diet using olive oil or a control low-fat diet. Plasma antioxidant capacity, endothelial function, nitrotyrosine, 8-iso-PGF2a, IL-6 and ICAM-1 levels were evaluated at baseline and at the end of the study. The effect of GLP-1 during a hyperglycemic clamp, was also studied at baseline and at the end of the study.

Results: Compared to the control diet, the Mediterranean diet increased plasma antioxidant capacity and improved basal endothelial function, nitrotyrosine, 8-iso-PGF2a, IL-6 and ICAM-1 levels. The Mediterranean diet also reduced the negative effects of acute hyperglycemia, induced by a hyperglycemic clamp, on endothelial function, nitrotyrosine, 8-iso-PGF2a, IL-6 and ICAM-1 levels. Furthermore, the Mediterranean diet improved the protective action of GLP-1 on endothelial function, nitrotyrosine, 8-iso-PGF2a, IL-6 and ICAM-1 levels, also increasing GLP-1-induced insulin secretion.

Conclusions: These data suggest that the Mediterranean diet, using olive oil, prevents the acute hyperglycemia effect on endothelial function, inflammation and oxidative stress, and improves the action of GLP-1, which may have a favorable effect on the management of type 2 diabetes, particularly for the prevention of cardiovascular disease.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Aged
  • Blood Glucose / metabolism
  • Cardiovascular Diseases / prevention & control*
  • Diabetes Mellitus, Type 2 / drug therapy*
  • Diet, Mediterranean*
  • Drug Resistance / drug effects
  • Endothelium, Vascular / drug effects*
  • Female
  • Glucagon-Like Peptide 1 / metabolism*
  • Humans
  • Hyperglycemia / prevention & control*
  • Inflammation / drug therapy
  • Male
  • Middle Aged
  • Oxidative Stress / drug effects

Substances

  • Blood Glucose
  • Glucagon-Like Peptide 1