Post-prandial rise of microvesicles in peripheral blood of healthy human donors

Abstract

Background: Microvesicles isolated from body fluids are membrane - enclosed fragments of cell interior which carry information on the status of the organism. It is yet unclear how metabolism affects the number and composition of microvesicles in isolates from the peripheral blood.

Aim: To study the post - prandial effect on microvesicles in isolates from the peripheral blood of 21 healthy donors, in relation to blood cholesterol and blood glucose concentrations.

Results: The average number of microvesicles in the isolates increased 5 hours post - prandially by 52%; the increase was statistically significant (p = 0.01) with the power P = 0.68, while the average total blood cholesterol concentration, average low density lipoprotein cholesterol concentration (LDL-C) and average high density lipoprotein cholesterol concentration (HDL-C) all remained within 2% of their fasting values. We found an 11% increase in triglycerides (p = 0.12) and a 6% decrease in blood glucose (p < 0.01, P = 0.74). The post - prandial number of microvesicles negatively correlated with the post - fasting total cholesterol concentration (r = - 0.46, p = 0.035) while the difference in the number of microvesicles in the isolates between post - prandial and post - fasting states negatively correlated with the respective difference in blood glucose concentration (r = - 0.39, p = 0.05).

Conclusions: In a population of healthy human subjects the number of microvesicles in isolates from peripheral blood increased in the post - prandial state. The increase in the number of microvesicles was affected by the fasting concentration of cholesterol and correlated with the decrease in blood glucose.

Figure 1

Scanning electron micrograph of an isolate from peripheral blood of a healthy human subject. A: numerous microvesicles (black arrow) and residual cells (white arrow), B: high magnification image of microvesicles.

Figure 2

A typical dot plot detected by the flow cytometer. FS: forward scattered light, PMT1: side scattered light. The three regions marked estimate R1: microspheres with 10 μm diameter, R2: residual cells and R3: microvesicles.

Figure 3

Flow cytometry histogram showing the intensity of fluorescent light emitted by microvesicles in the post - fasting and in the post - prandial states. PMT4 detects light expected from anti-CD42b-PE molecules.