Changes in peripheral inflammation-related gene expression by postprandial glycemic response in healthy Japanese men

Continuous postprandial hyperglycemia is associated with the onset of cardiovascular disease. In recent years, the mRNA expression of inflammation-related genes in peripheral blood leukocytes has been shown to be induced by an increase in blood glucose levels. The aim of this study was to investigate differences in the expression of inflammation-related genes in peripheral blood leukocytes in response to an increase in blood glucose from individuals who consumed two kinds of breakfast meals with different glycemic indexes (GIs).

Twenty healthy Japanese men 40 to 70 y of age were given low- or high-GI meals for breakfast for 14 d. Clinical examinations were performed on days 7 and 14. Their blood glucose levels and insulin concentrations were measured from before breakfast ingestion to 120 min after. Additionally, using the blood obtained before and 120 min after breakfast, the mRNA expression levels of inflammation-related genes in peripheral leukocytes were measured.

The blood glucose levels were significantly lower in the low-GI meal intake group at 30, 60, and 120 min after breakfast than in the high-GI meal intake group. The intake of high-GI meals for 6 d led to an increase in the mRNA levels of interleukin-1β, S100A4, and CD18 compared with the period of low-GI meals.

The intake of a low-GI breakfast for 1 wk in healthy Japanese men resulted in lower postprandial blood glucose and insulin levels, which were accompanied by a reduced expression of inflammation-related genes in peripheral blood leukocytes.