目的:糖尿病是一种影响肾素-血管紧张素系统(RAS)功能的多因素综合征。晚期糖基化终产物(AGEs)在糖尿病中的作用是众所周知的。在本研究中,我们假设使用AGE抑制剂预防AGE积累或废除AGE合成,氨基胍(AG),在链脲佐菌素(STZ)诱导的糖尿病动物模型中,会影响糖尿病及其相关并发症的进展。我们确定了氨基胍(AG)的作用,AGE抑制剂,在STZ诱导的糖尿病大鼠中,通过测定RAS和肾功能的各种指标。此外,我们还调查了这种药物的效果,AG,动物体内的各种血液动力学和生理功能。
方法:体重为200-250g的雄性SpragueDawley大鼠分为四组(n=4-6):载体,车辆+AG,STZ诱导,和STZ诱导的+AG大鼠。通过单次腹膜内(IP)注射溶解在柠檬酸钠缓冲液中的链脲佐菌素(55mg/kg)诱导1型糖尿病。对照组(媒介物)注射缓冲液。48小时后测量血糖水平,和血糖水平>300mg/dL的动物被包括在研究中。还测定载体大鼠中的血糖水平以确保非糖尿病状况。确认后,AG在饮用水中以1g/L的剂量给药两周。收集尿液以测量肾小球滤过率(GFR),并通过免疫印迹分析AT1和AT2蛋白的免疫反应性。数据表示为平均值±平均值的标准误差(SEM),并且p值<0.05被认为具有统计学意义。
结果:糖尿病大鼠体重明显下降,伴随着食物和水消耗的增加。糖尿病大鼠表现出显著增加的尿流量和GFR。在STZAG治疗的糖尿病大鼠中,通过AG治疗,这些表型被显着或彻底逆转。与单独使用STZ诱导的糖尿病大鼠相比,氨基胍阻止了血糖水平的增加(295.9±50.69对462.3±18.6mg/dL(p<0.05))。然而,它不影响肾小球滤过率(GFR)和肾小球损伤,通过肾组织病理学研究评估。STZ诱导的糖尿病大鼠的钠排泄增加(3.24±0.40mmol),AT2受体和AT1受体的表达显着增加,用AG治疗略有逆转。用AG治疗可减少钠排泄(与糖尿病大鼠相比,为2.12±0.63)。这些大鼠的AT2受体表达也略有下降(与STZ诱导的糖尿病大鼠相比,0.99±0.07对1.12±0.08),与STZ诱导的糖尿病大鼠相比,STZAG治疗的大鼠AT1受体略有增加(1.1±0.19对1.08±0.12)。
结论:本研究强调了药物AG在不加重糖尿病大鼠的任何损伤中的作用。使用AG作为防止血糖升高的药物干预措施增加了控制血糖升高和预防糖尿病并发症的新维度。药物AG的就业能力和药理干预,在糖尿病中,因此,需要重新和进一步的调查。
OBJECTIVE: Diabetes is a multifactorial syndrome that affects the functioning of the renin-angiotensin system (RAS). The role of advanced glycation end products (AGEs) in diabetes is well known. In the present study, we hypothesized that the prevention of AGE accumulation or abrogation of AGE synthesis using an AGE inhibitor, aminoguanidine (AG), in streptozotocin (STZ)-induced diabetic animal models would affect the progression of diabetes and its related complications. We determined the effects of aminoguanidine (AG), an AGE inhibitor, in STZ-induced diabetic rats by determining various indices of RAS and renal functions. Additionally, we also investigated the effect of the drug, AG, on various hemodynamic and physiological functions in the body of the animals.
METHODS: Male Sprague Dawley rats weighing 200-250 g were assigned to four groups (n = 4-6): Vehicle, Vehicle+AG, STZ-induced, and STZ-induced+AG rats. Type 1 diabetes was induced by a single intraperitoneal (IP) injection of streptozotocin (55 mg/kg) dissolved in sodium citrate buffer. The control groups (Vehicle) were injected with buffer. The blood glucose levels were measured after 48 hours, and animals with blood glucose levels > 300 mg/dL were included in the study. Blood glucose levels in the vehicle rats were also determined to ensure non-diabetic conditions. After confirmation, AG was administrated at a dose of 1 g/L in drinking water for two weeks. Urine was collected to measure the glomerular filtration rate (GFR), and the immune reactivity for AT1 and AT2 proteins was analyzed by immunoblotting. Data were expressed as mean ± standard error of the mean (SEM), and a p-value < 0.05 was considered statistically significant.
RESULTS: Diabetic rats had a significant drop in body weight, accompanied by increased food and water consumption. The diabetic rats exhibited significantly increased urine flow and GFR. These phenotypes were significantly or considerately reversed by AG treatment in the STZ+AG-treated diabetic rats. Aminoguanidine prevented the increase in blood sugar levels compared to STZ-induced diabetic rats alone (295.9 ± 50.69 versus 462.3 ± 18.6 mg/dL (p < 0.05)). However, it did not affect the glomerular filtration rate (GFR) and glomerular damage, as assessed by the renal histopathological studies. The STZ-induced diabetic rats had an increased sodium excretion (3.24 ± 0.40 mmol) and significantly increased expression of the AT2 receptor and that of the AT1 receptor, which was slightly reversed by the treatment with AG. Treatment with AG decreased sodium excretion (2.12 ± 0.63, as compared to the diabetic rats). These rats also had modestly decreased expression of the AT2 receptor (0.99 ± 0.07 versus 1.12 ± 0.08, as compared to the STZ-induced diabetic rats), while the AT1 receptors showed a slight increase in the STZ+AG-treated rats compared to the STZ-induced diabetic rats (1.1 ± 0.19 versus 1.08 ± 0.12).
CONCLUSIONS: This study highlights the action of the drug AG in not exacerbating any damage in diabetic rats. Employing AG as a pharmacological intervention to prevent an increase in blood sugar adds a new dimension to controlling increased blood sugar and preventing diabetic complications. The employability and pharmacological intervention of the drug AG, in diabetes, therefore, need a renewed and further investigation.