Lin Yi-Tsen, Tseng Yung-Zu, Chang Kuo-Chu
Department of Physiology, College of Medicine, National Taiwan University, No. 1, Sec. 1, Jen-Ai Road, Taipei, Taiwan.
Exp Biol Med (Maywood). 2004 Nov;229(10):1038-45. doi: 10.1177/153537020422901008.
Fructose has been reported as a potent agent in forming advanced glycation end products (AGEs) and, thus, may play a significant role in the pathogenesis of diabetic complications. Herein, we determined the effects of aminoguanidine (AG), an inhibitor of AGEs, on the mechanical properties of the arterial system in fructose-fed (FF) rats, using aortic impedance analysis. Rats at 2 months were given 10% fructose in drinking water for 2 weeks and compared with untreated age-matched controls. Meanwhile, FF rats were treated for 2 weeks with AG (daily peritoneal injections of 50 mg kg(-1)) and compared with the untreated FF group. Neither fructose nor AG affects body weight, blood glucose level, and basal heart rate. In comparison with controls, FF rats showed a decrease in cardiac output in the absence of any significant changes in mean aortic pressure, having increased total peripheral resistance (R(p)), at 51.1 +/- 2.9 versus 66.2 +/- 1.9 mm Hg sec ml(-1) (P < 0.05). Fructose also contributed to an increase in aortic characteristic impedance (Z(c)), from 1.528 +/- 0.094 to 1.933 +/- 0.084 mm Hg sec ml (-1) (P < 0.05) and a decrease in wave transit time (tau), from 22.6 +/- 0.6 to 19.2 +/- 0.7 msec (P < 0.05). The elevated Z(c) and the reduced tau suggest that fructose may cause a detriment to the aortic distensibility in animals. After exposure to AG, FF rats exhibited a significant improvement in physical properties of the resistance vessels, as evidenced by the reduction of 21.3% in R(p). Meanwhile, AG retarded the fructose-induced decline in aortic distensibility, as reflected in the decrease of 16.0% in Z(c) (P < 0.05) and the increase of 18.1% in tau (P < 0.05). By contrast, AG exerted no effects on the mechanical properties of Windkessel vessels, as well as resistance vessels, in normal diet controls. We conclude that AG may prevent the fructose-derived changes in arterial stiffening, possibly through inhibition of the fructose-derived advanced glycation end product formation in Wistar rats.
据报道,果糖是形成晚期糖基化终末产物(AGEs)的强效因子,因此可能在糖尿病并发症的发病机制中起重要作用。在此,我们使用主动脉阻抗分析,确定了AGEs抑制剂氨基胍(AG)对喂食果糖(FF)大鼠动脉系统力学性能的影响。2月龄大鼠饮用含10%果糖的水2周,并与未处理的年龄匹配对照组进行比较。同时,FF大鼠用AG处理2周(每日腹腔注射50 mg kg(-1)),并与未处理的FF组进行比较。果糖和AG均不影响体重、血糖水平和基础心率。与对照组相比,FF大鼠的心输出量降低,而平均主动脉压无显著变化,总外周阻力(R(p))增加,分别为51.1±2.9与66.2±1.9 mmHg sec ml(-1)(P<0.05)。果糖还导致主动脉特征阻抗(Z(c))增加,从1.528±0.094增加到1.933±0.084 mmHg sec ml (-1)(P<0.05),波传播时间(tau)缩短,从22.6±0.6缩短到19.2±0.7 msec(P<0.05)。Z(c)升高和tau降低表明果糖可能损害动物的主动脉扩张性。暴露于AG后,FF大鼠阻力血管的物理性能有显著改善,R(p)降低21.3%证明了这一点。同时,AG减缓了果糖诱导的主动脉扩张性下降,表现为Z(c)降低16.0%(P<0.05)和tau增加18.1%(P<0.05)。相比之下,AG对正常饮食对照组的Windkessel血管以及阻力血管的力学性能没有影响。我们得出结论,AG可能通过抑制Wistar大鼠中果糖衍生的晚期糖基化终末产物形成,预防果糖引起的动脉僵硬变化。