Sözmen E Y, Sözmen B, Delen Y, Onat T
Department of Biochemistry, Ege University School of Medicine, Bornova-Izmir, Turkey.
Arch Med Res. 2001 Jul-Aug;32(4):283-7. doi: 10.1016/s0188-4409(01)00285-5.
Previous studies suggest that elevated oxidative stress implicates poor glycemic control resulting in the development of diabetic complications. By evaluating the relationship between paraoxonase (PON) and antioxidant enzyme activities and glycemic control in diabetic patients with and without complications, we investigated whether there is a role of PON and/or antioxidant status in glycemic control.
A total of 107 patients with type 2 diabetes mellitus (DM) was included in the study. Seventy-five patients had complications including microangiopathy, proliferative retinopathy, and/or nephropathy while 32 had no complications. The control group consisted of 29 age- and sex-matched healthy persons. Serum superoxide dismutase (SOD) and catalase activities were measured according to Sun and Goth, respectively. Basal and salt-stimulated paraoxonase activities and arylesterase activity were determined using the method of Eckerson et al.
There was an increase in the catalase activity and a decrease in the basal and salt-stimulated PON activity of patients when compared with controls, while no significant difference was observed in SOD activity. PON phenotypes had no effect on any parameter in patient and control groups. The ratio of catalase/SOD was 2.44 +/- 7.10 and 0.17 +/- 0.09 in diabetics and controls, respectively (p = 0.004); this was associated with an elevation in HbA1c levels. On the other hand, catalase/PON ratio was also enhanced in diabetic patients (2.8 +/- 5.2), showing a relationship with HbA1c levels compared to controls (0.29 +/- 0.3, p = 0.000).
The data of this study reveal that enhanced catalase/SOD and catalase /PON ratios that are correlated with HbA1c levels are observed in diabetic patients; thus, these ratios may be used as markers of poor glycemic control and as risk factors in the development of diabetic complications.
先前的研究表明，氧化应激升高意味着血糖控制不佳，进而导致糖尿病并发症的发生。通过评估对氧磷酶（PON）与抗氧化酶活性之间的关系以及有无并发症的糖尿病患者的血糖控制情况，我们研究了PON和/或抗氧化状态在血糖控制中是否起作用。
本研究共纳入107例2型糖尿病（DM）患者。75例患者有并发症，包括微血管病变、增殖性视网膜病变和/或肾病，而32例无并发症。对照组由29名年龄和性别匹配的健康人组成。血清超氧化物歧化酶（SOD）活性和过氧化氢酶活性分别根据Sun和Goth的方法进行测定。基础和盐刺激后的对氧磷酶活性及芳基酯酶活性采用Eckerson等人的方法进行测定。
与对照组相比，患者的过氧化氢酶活性升高，基础和盐刺激后的PON活性降低，而SOD活性未观察到显著差异。PON表型对患者组和对照组的任何参数均无影响。糖尿病患者和对照组的过氧化氢酶/SOD比值分别为2.44±7.10和0.17±0.09（p = 0.004）；这与糖化血红蛋白（HbA1c）水平升高相关。另一方面，糖尿病患者的过氧化氢酶/PON比值也升高（2.8±5.2），与对照组相比显示出与HbA1c水平的关系（0.29±0.3，p = 0.000）。
本研究数据显示，在糖尿病患者中观察到与HbA1c水平相关的过氧化氢酶/SOD和过氧化氢酶/PON比值升高；因此，这些比值可作为血糖控制不佳的标志物以及糖尿病并发症发生的危险因素。
