Macro- and Microvascular Response to Cocoa Flavanols in Healthy and Type 2 Diabetes

Proof-of-concept Study to Investigate Hand and Foot Microvascular Response to Cocoa Flavanols in Healthy and Type 2 Diabetes Participant

The greatest challenge in our ageing society are cardiovascular diseases such as stroke, heart attack, peripheral artery disease of the legs with non-healing wounds (ulcers), or diabetes. Specific diets with high polyphenol content are associated with lower incidence of cardiovascular disease and can improve macrovascular function when consumed acutely and chronically. Which role the smallest blood vessels (microcirculation) play in this and if the microcirculation responds to therapies is not well understood. One reason for this is that no generally available medical instrument has the resolution to study the microcirculation. The recently developed optical coherence tomography angiography (OCTA), currently mainly used by eye doctors, is able to visualise the microcirculation. The current randomised controlled cross-over proof-of-concept study will test the acute effect of a cocoa flavanol intervention on cutaneous microvascular structure and function of hands and feet together with macrovascular function of upper and lower extremities in healthy and type 2 diabetes participants. It is the hypothesis that cocoa flavanol intervention as compared to placebo can acutely increase microvascular vasodilation and macrovascular endothelial function in arms and legs together with arterial stiffness in both healthy and type 2 diabetes participants.

Microangiopathy, Diabetic, Polyphenol, Optical Tomography, Vascular Endothelium, Arterial Stiffness, Healthy Participants

Participants with type 2 diabetes receiving cocoa flavanols on first study day and placebo on second study day

Participants with type 2 diabetes receiving placebo on first study day and cocoa flavanols on second study day

Capsules identical to ccocoa flavanol capsules filled with calorically matched brown sugar (6 capsules)

Healthy: Inclusion Criteria: Healthy, 20-70 years BMI 20-30 kg/m^2 Exclusion Criteria: Diabetes mellitus Symptoms of acute infection Cardiac rhythm other than sinus Active malignancy Clinical signs or symptoms of cardiovascular disease (coronary artery disease, lower extremity artery disease, cerebrovascular disease): angina pectoris, dyspnea, palpitation, syncope, claudication Active vasoactive medication. Type 2 Diabetes: Inclusion Criteria: Type 2 diabetes mellitus 20-70 years BMI 20-30 kg/m^2 Exclusion Criteria: Symptoms of acute infection Cardiac rhythm other than sinus Active malignancy Clinical signs or symptoms of cardiovascular disease (coronary artery disease, lower extremity artery disease, cerebrovascular disease): angina pectoris, dyspnea, palpitation, syncope, claudication Active vasoactive medication.