Abstract: Objective To investigate the effect of blood glucose instability on respiratory burst of leukocytes in patients with
type 2 diabetes (T2DM). Methods Forty-five patients with T2DM were divided into 3 groups after continuous glucose
monitoring for 72 h with glucose wavy coefficient <1.5 (n=11), between 1.5 and 3.0 (n=19), and >3.0 (n=15). Peripheral blood
neutrophils were isolated from the diabetic patients and normal control subjects for assay of glucose 6-phosphate
dehydrogenase (G6PD) with a spectrophotometric method, detecting G6PD mRNA expression by real-time PCR, and
determining reactive oxygen species level using the fluorescent probe DCFH-DA. Results Compared with the normal control
group, the diabetic patients showed significantly lowered G6PD activity (F=78.739, P<0.05) and ROS level (F=384.962, P<0.05)
but significantly increased G6PD mRNA expression (F=269.612, P<0.01). These changes were significantly correlated with the
blood glucose wavy coefficients. Conclusion The fluctuation of blood glucose in T2DM patients can decrease G6PD activity
and lead to functional decline of the respiratory burst.