Berndt-Zipfel Christine, Michelson Georg, Dworak Markus, Mitry Michael, Löffler Andrea, Pfützner Andreas, Forst Thomas
Cardiovasc Diabetol. 2013 Apr 8;12:59. doi: 10.1186/1475-2840-12-59.
Numerous rheological and microvascular alterations characterize the vascular pathology in patients with type 2 diabetes mellitus (T2DM). This study investigated effects of vildagliptin in comparison to glimepiride on retinal microvascular blood flow and erythrocyte deformability in T2DM.Fourty-four patients with T2DM on metformin monotherapy were included in this randomized, exploratory study over 24 weeks. Patients were randomized to receive either vildagliptin (50 mg twice daily) or glimepiride individually titrated up to 4 mg in addition to ongoing metformin treatment. Retinal microvascular blood flow (RBF)and the arteriolar wall to lumen ratio (WLR) were assessed using a laser doppler scanner. In addition, the rythrocyte elongation index (EI) was measured at different shear stresses using laserdiffractoscopy.Both treatments improved glycaemic control (p < 0.05 vs. baseline; respectively). While only slight changes in RBF and the WLR could be observed during treatment with glimepiride, vildagliptin significantly increased retinal bloodflow and decreased the arterial WLR (p < 0.05 vs. baseline respectively). The EI increased during both treatments over a wide range of applied shear stresses (p < 0.05 vs. baseline). An inverse correlation could be observed between improved glycaemic control (HbA1c) and EI (r = -0.524; p < 0.0001) but not with the changes in retinal microvascular measurements.Our results suggest that vildagliptin might exert beneficial effects on retinal microvascular blood flow beyond glucose control. In contrast, the improvement in erythrocyte deformability observed in both treatment groups,seems to be a correlate of improved glycaemic control.
许多流变学和微血管改变是2型糖尿病（T2DM）患者血管病变的特征。本研究调查了与格列美脲相比，维格列汀对T2DM患者视网膜微血管血流和红细胞变形性的影响。44例接受二甲双胍单药治疗的T2DM患者被纳入这项为期24周的随机探索性研究。患者被随机分为接受维格列汀（每日两次，每次50 mg）或格列美脲，除正在进行的二甲双胍治疗外，格列美脲需单独滴定至4 mg。使用激光多普勒扫描仪评估视网膜微血管血流（RBF）和小动脉壁腔比（WLR）。此外，使用激光衍射法在不同切应力下测量红细胞伸长指数（EI）。两种治疗均改善了血糖控制（分别与基线相比，p<0.05）。在用格列美脲治疗期间，仅观察到RBF和WLR有轻微变化，而维格列汀显著增加了视网膜血流并降低了动脉WLR（分别与基线相比，p<0.05）。在两种治疗期间，在广泛的应用切应力范围内EI均增加（与基线相比，p<0.05）。在改善的血糖控制（糖化血红蛋白）与EI之间可观察到负相关（r=-0.524；p<0.0001），但与视网膜微血管测量的变化无关。我们的结果表明，维格列汀可能在血糖控制之外对视网膜微血管血流发挥有益作用。相比之下，在两个治疗组中观察到的红细胞变形性改善似乎与血糖控制改善相关。
