糖尿病肾病动物模型的研究进展

糖尿病肾病是终末期肾衰的主要原因,也是糖尿病致命的重要原因。但是糖尿病肾病的致病机制迄今尚不完全明了,理想的动物模型无疑可对糖尿病肾病的研究提供重要线索。糖尿病肾病动物模型包括诱发性、自发性和转基因等多种类型的动物模型,各种类型的动物模型在疾病的发生发展、病理生理变化等多个方面与人类糖尿病肾病具有相似的特征。应用这些模型有助于开展对糖尿病肾病的防治、发病机理、相关药物的开发等多方面的研究。     

糖尿病肾病啮齿动物模型研究进展*

糖尿病肾病(Diabetic nephropathy,DN),是糖尿病微血管病变中常见的并发症,也是发展为终末期肾病(End stage renaldisease,ESRD)的主要原因之一,其病因与发病机制非常复杂,至今尚未完全阐明。理想的动物模型研究对于探索DN的病因、发病机制,发病早期作出诊断、发现临床相关治疗靶点并探索新的治疗方法,评价干预措施等方面有着不可替代的作用。本文现就目前国内外常用的DN啮齿动物模型展开综述,探讨不同DN啮齿动物模型的特点和应用范围。     

蛋白质组学在糖尿病肾病研究中的应用

糖尿病肾病作为糖尿病的主要并发症之一,是导致终末期肾功能衰竭(end-stage renal disease,ERSD)的最主要原因之一。目前,人们对糖尿病肾病的发病机制尚不完全清楚。近年来蛋白质组学技术逐渐被应用于这一疾病发病机制的研究中,为人们探索糖尿病肾病的发病机制提供了有力的实验依据。本文对蛋白质组学在糖尿病肾病研究中的新近进展进行了综述和讨论,并通过具体实例介绍了如何对蛋白质组学数据进行系统分析,揭示潜在的新调控网络及其生理与病理生理意义,为糖尿病肾病的研究与治疗提供新的思路。     

糖尿病肾病的发病机制和药物干预研究进展

糖尿病肾病作为糖尿病最严重的并发症之一,也是糖尿病患者最主要的死亡原因之一。糖尿病肾病的发病机制主要与代谢紊乱、 血流动力学紊乱、氧化应激、炎症及遗传因素等相关。综述糖尿病肾病发病机制及相关药物治疗的研究新进展,为糖尿病肾病的早期干 预和治疗提供参考。     

糖尿病肾病遗传学研究进展

糖尿病肾病是糖尿病最严重的慢性并发症之一, 不同种族的发病率分析和家族聚集性研究显示遗传因素是糖尿病肾病发生、发展的重要因素。文章从3个方面对糖尿病肾病的遗传学研究进展进行综述：“候选基因”的关联研究、连锁分析和全基因组关联研究。关联研究及荟萃分析显示一些候选基因与糖尿病肾病显著相关, 包括ACE、AGT和PPARG等基因; 连锁分析及全基因组连锁分析发现多个糖尿病肾病的易感染色体位点; 随着高通量测序技术和芯片技术的发展, 全基因组关联研究已成为糖尿病肾病遗传学研究的重要途径。虽然遗传因素在糖尿病肾病发病中占据重要的位置, 但还不能完全解释糖尿病肾病的发病原因, 因为糖尿病肾病的发生还受环境因素的影响, 然而糖尿病肾病的遗传学研究可为糖尿病肾病发病机制研究以及药物治疗靶点研究提供一定的理论依据。     

大鼠糖尿病溃疡动物模型的初步研究

目的构建大鼠糖尿病溃疡动物模型,观察评价该模型的临床及病理特点。方法利用磁片循环压迫的方法,构建大鼠糖尿病溃疡动物模型,并从整体,组织和生化三个层次对糖尿病溃疡进行了研究。结果构建出了一个可以复制的糖尿病溃疡动物模型,该模型具有组织坏死、白细胞聚集以及高浓度晚期糖化终末产物等特征。结论利用缺血再灌注法构建了大鼠糖尿病溃疡动物模型。其病理改变与人极为相似,是一种很好的用于糖尿病溃疡发病机制和治疗研究的动物模型。     

实验性链脲佐菌素诱导的大、小鼠糖尿病动物模型研究进展

糖尿病正呈快速上升趋势,而糖尿病的病因、发病机制尚未完全阐明,糖尿病及其并发症的预防和治疗仍不完善。因此,在糖尿病研究领域优化糖尿病实验动物模型的研究,寻找更接近人类糖尿病自然发病过程的动物模型,对于深入研究糖尿病具有重要的科学意义。     

糖尿病肾病主要发病机制的研究进展

糖尿病肾病是糖尿病微血管并发症之一,同时也是引起终末期肾脏病的重要病因。临床上主要以持续存在的白蛋白尿和(或)肾小球滤过率进行性下降为特征。糖尿病肾病致病机制复杂,目前普遍认为氧化应激、炎症和自噬是其主要的发病机制。临床上还没有针对糖尿病肾病治疗的药物,糖尿病肾病的治疗依然是亟待攻克的一个重点和难点。现对影响糖尿病肾病进展的三大主要发病机制进行一个总结性概括,以期为糖尿病肾病药物的研发带来一些新的思路和启发。     

线粒体功能障碍在糖尿病肾病进展的作用

糖尿病肾病是糖尿病微血管并发症之一,亦是引起终末期肾脏病的主要原因。目前各种临床治疗手段并没有阻止糖尿病肾病患者肾功能的进行性减退。因此,当务之急是进一步研究糖尿病肾病的发病机制,并从中寻找新的治疗靶点。大量研究结果显示线粒体功能障碍在糖尿病肾病的发生发展过程中具有重要作用。正常线粒体功能的维持依赖于多方面因素的共同参与,如线粒体质量控制机制、线粒体DNA等。这篇综述回顾了关于线粒体与糖尿病肾病相关文献,阐述线粒体功能障碍在糖尿病肾病进展中可能的作用。     

Ⅱ型糖尿病动物模型的构建

动物模型在Ⅱ型糖尿病研究中发挥重要作用,对于深入研究糖尿病及其并发症的发病、预防、诊断和治疗有重要意义。本文就Ⅱ型糖尿病动物模型的构建进行了概述,对发展新型构建糖尿病模型的方法具有重要的参考价值。     

糖尿病肾病发病分子机制

糖尿病肾病(DN)是高血糖所导致的一种主要的微血管并发症。在全世界糖尿病病人中,糖尿病肾病都有着非常高的发病率和致死率。并且在中国,糖尿病肾病已经成为一种常见的导致末期肾衰竭的因素。由于糖尿病肾病患者不断增多,传统的单纯通过控制血糖来控制糖尿病肾病并没有取得理想的效果,因此临床上迫切需要一些新的治疗方法来控制糖尿病肾病的发生和发展。最近的研究表明肾素-血管紧张素-醛固酮系统(RAAS)、蛋白激酶-C(PKC)、还原型烟酰胺腺嘌呤二核苷酸磷酸(NADPH)氧化酶、转化生长因子-β(TGF-β)等都单独的或共同的参与了DN的发生和发展过程。这些通路彼此交叉,十分复杂,因此需要对糖尿病肾病发病分子机制进行全面的综合的理解。这篇文章旨在讨论已发现的与糖尿病肾病密切相关的分子机制以及下调通路。     

mTOR信号通路在糖尿病肾病发病机制中的研究进展

糖尿病肾病（diabetic nephropathy,DN）是糖尿病最常见的并发症之一,因其具有高发病率且与晚期肾病、心血管疾病和过早死亡等风险相关,糖尿病肾病已成为全球性的公共健康问题,但目前其发病机制尚不清楚。雷帕霉素靶蛋白（mammalian target of rapamycin,mTOR）是一种丝氨酸/苏氨酸的蛋白酶,在延迟细胞凋亡以及促进细胞分裂、细胞存活、血管生成中发挥着重要作用。近年来有研究表明,mTOR存在于DN进展的关键步骤中,包括自噬、炎症及氧化应激等。因此,就mTOR介导的自噬、炎症及氧化应激信号通路在DN发病机制中的相关研究进展做一综述,以期为DN治疗及预防提供理论参考。     

Sinensetin ameliorates high glucose-induced diabetic nephropathy via enhancing autophagy in vitro and in vivo

Diabetic nephropathy (DN) affects around 40% of people with diabetes, the final outcome of which is end-stage renal disease. The deficiency of autophagy and excessive oxidative stress have been found to participate in the pathogenesis of DN. Sinensetin (SIN) has been proven to have strong antioxidant capability. However, the effect of SIN on DN has not been studied. We examined the effect of SIN on cell viability and autophagy in the podocyte cell line, MPC5 cells, treated with high glucose (HG). For in vivo studies, DN mice models were established by intraperitoneal injected with streptozotocin (40 mg/kg) for 5 consecutive days and fed with a 60% high-fat diet, and SIN was given (10, 20, and 40 mg/kg) for 8 weeks via intraperitoneal injection. The results showed that SIN could protect MPC5 cells against HG-induced damage and significantly improve the renal function of DN mice. Moreover, SIN remarkably restored the autophagy activity of MPC5 cells which was inhibited under HG conditions. Consistent with this, SIN efficiently improved autophagy in the kidney tissue of DN mice. In brief, our findings demonstrated the protective effect of SIN on DN via restoring the autophagic function, which might provide a basis for drug development.     

Elevated Serum Levels of Mannose-Binding Lectin and Diabetic Nephropathy in Type 2 Diabetes

Objective

Inflammation and complement activation initiated by mannose-binding lectin (MBL) may be implicated in the pathogenesis of diabetic vascular complications. We investigated serum MBL levels in type 2 diabetes with diabetic nephropathy (DN) and with persistent normoalbuminuria.

Method

Serum MBL levels were determined in 242 type 2 diabetes with overt nephropathy and 242 type 2 diabetes with persistent normoalbuminuria matched for age, sex, and duration of diabetes, as well as in 100 healthy control subjects. The prediction value of MBL was compared with HbA1c, Hs-CRP and with other known predictors. Multivariate analyses were performed using logistic regression models.

Results

The serum MBL levels were significantly higher in diabetes with DN as compared to with persistent normoalbuminuria (P<0.0001). Multivariate logistic regression analysis adjusted for common factors showed that serum MBL levels≥2950ug/L was an independent indictor of DN (OR=7.55; 95%CI: 3.44–19.04). Based on the ROC curve, the optimal cutoff value of serum MBL levels as an indicator for diagnosis of DN was projected to be 2950ug/L, which yielded a sensitivity of 77.2 % and a specificity of 80.8%, with the area under the curve at 0.809 (95%CI, 0.769—0.848).

Conclusion

Our findings suggested that MBL may be involved in the pathogenesis of DN in type 2 diabetes, and that determination of MBL status might be used to identify patients at increased risk of developing nephropathy complications.     

Molecular genetic approaches for studying the etiology of diabetic nephropathy

A critical challenge faced by clinical nephrologists today is the escalating number of patients developing end stage renal disease, a major proportion of which is attributed to diabetic nephropathy (DN). The need for new measures to prevent and treat this disease cannot be overemphasized. To this end, modern genetic approaches provide powerful tools to investigate the etiology of DN. Human studies have already established the importance of genetic susceptibility for DN. Several major susceptibility loci have been identified using linkage studies. In addition, linkage studies in rodents have pinpointed promising chromosomal segments that influence renal traits. Besides augmenting our understanding of disease pathogenesis, these animal studies may facilitate the cloning of disease susceptibility genes in man through the identification of homologous regions that contribute to renal disease. In human diabetes, various genes have been evaluated for their risk contribution to DN. This widespread strategy has been propelled by our knowledge of the glucose-activated pathways underlying DN. Evidence has emerged that a true association does indeed exist for some candidate genes. Furthermore, the in vivo manipulation of gene expression has shown that these genes can modify features of DN in transgenic and knockout rodent models, thus corroborating the findings from human association studies. Still, the exact molecular mechanisms involving these genes remain to be fully elucidated. This formidable task may be accomplished by continuing to harness the synergy between human and experimental genetic approaches. In this respect, our review provides a first synthesis of the current literature to facilitate this challenging effort.     

DUSP1 recuses diabetic nephropathy via repressing JNK-Mff-mitochondrial fission pathways

Excessive mitochondrial fission has been identified as the pathogenesis of diabetic nephropathy (DN), although the upstream regulatory signal for mitochondrial fission activation in the setting of DN remains unknown. In the current study, we found that dual-specificity protein phosphatase-1 (DUSP1) was actually downregulated by chronic hyperglycemia stimulus. Lower DUSP1 expression was associated with glucose metabolism disorder, renal dysfunction, kidney hypertrophy, renal fibrosis, and glomerular apoptosis. At the molecular level, defective DUSP1 expression activated JNK pathway, and the latter selectively opened mitochondrial fission by modulating mitochondrial fission factor (Mff) phosphorylation. Excessive Mff-related mitochondrial fission evoked mitochondrial oxidative stress, promoted mPTP opening, exacerbated proapoptotic protein leakage into the cytoplasm, and finally initiated mitochondria-dependent cellular apoptosis in the setting of diabetes. However, overexpression of DUSP1 interrupted Mff-related mitochondrial fission, reducing hyperglycemia-mediated mitochondrial damage and thus improving renal function. Overall, we have shown that DUSP1 functions as a novel malefactor in diabetic renal damage that mediates via modifying Mff-related mitochondrial fission. Thus, finding strategies to regulate the balance of the DUSP1-JNK-Mff signaling pathway and mitochondrial homeostasis may be a therapeutic target for treating diabetic nephropathy in clinical practice.     

Gene polymorphisms in patients with type 2 diabetes and diabetic nephropathy

A considerable variability in the incidence and prevalence of diabetic nephropathy (DN) coheres with an important contribution of multigenetic predisposition in the development of DN. Some genes, which probably participate in the pathogenesis of diabetic nephropathy, also play a role in the regulation of blood pressure, familial hyperlipidemia, familial hypertension and other diseases of the cardiovascular system. We have examined the association of diabetic nephropathy, nephropathy of non-diabetic origin, hypertension and of type 2 diabetes itself with several genetic polymorphisms (the insertion/deletion polymorphism in the gene for angiotensin-converting enzyme, the G/T polymorphism in the glucose transporter 1 gene, the G/T (894) polymorphism and the T/C (−786) polymorphism in the eNOS gene in three groups of patients with diabetes mellitus: 1) patients without diabetic nephropathy (DM); 2) patients with DN; 3) patients with nephropathy of non-diabetic origin (NDRD). Angiotensin-converting enzyme is an important factor in a development of arterial hypertension, but in our groups of Central European diabetic patients the I/D polymorphism was not associated with diabetic nephropathy. Furthermore, we have confirmed that the T/C (T786C) polymorphism in the eNOS gene is associated with metabolic syndrome including type 2 diabetes.     

A novel improved therapy strategy for diabetic nephropathy

Diabetic nephropathy (DN), is a disorder that causes significant morbidity and mortality. Studies on the pathological mechanisms of DN reveal that advanced glycation end products (AGEs) play an important role in the pathogenesis of DN through interacting with receptors for advanced glycation end products (RAGE), which activate a series of intracellular signaling pathways. AGEs and RAGE have therefore been considered to be two potential key targets. Although multiple studies have been made for anti-DN therapy against AGEs or RAGE, the results have been disappointing due to poor effectiveness or to side effects in clinical practice. In this hypothesis article, we propose a novel treatment based on a dual-target approach. A kind of multi-functional intelligent nanoparticle is constructed, which has a core-shell nanoparticle structure to load the dual-target drugs (AGEs inhibitors and RAGE inhibitors), and has a functional “RAGE analog” to be used as “bait” to catch AGEs and target them to the kidney. Owing to its advantages of having a dual-target, synergistic effect and high efficiency, the proposition may have potential applications in DN therapy.