Silva Carolina, Sampaio-Pinto Vasco, Andrade Sara, Rodrigues Ilda, Costa Raquel, Guerreiro Susana, Carvalho Eugenia, Pinto-do-Ó Perpétua, Nascimento Diana S, Soares Raquel
Department of Biomedicine, Unit of Biochemistry, Faculty of Medicine of the University of Porto, Porto, Portugal.
i3S, Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.
Cell Physiol Biochem. 2019;52(3):503-516. doi: 10.33594/000000036.
BACKGROUND/AIMS: Vascular complications contribute significantly to the extensive morbidity and mortality rates observed in people with diabetes. Despite well known that the diabetic kidney and heart exhibit imbalanced angiogenesis, the mechanisms implicated in this angiogenic paradox remain unknown. In this study, we examined the angiogenic and metabolic gene expression profile (GEP) of endothelial cells (ECs) isolated from a mouse model with type1 diabetes mellitus (T1DM).
ECs were isolated from kidneys and hearts of healthy and streptozocin (STZ)-treated mice. RNA was then extracted for molecular studies. GEP of 84 angiogenic and 84 AMP-activated Protein Kinase (AMPK)-dependent genes were examined by microarrays. Real time PCR confirmed the changes observed in significantly altered genes. Microvessel density (MVD) was analysed by immunohistochemistry, fibrosis was assessed by the Sirius red histological staining and connective tissue growth factor (CTGF) was quantified by ELISA.
The relative percentage of ECs and MVD were increased in the kidneys of T1DM animals whereas the opposite trend was observed in the hearts of diabetic mice. Accordingly, the majority of AMPK-associated genes were upregulated in kidneys and downregulated in hearts of these animals. Angiogenic GEP revealed significant differences in Tgfβ, Notch signaling and Timp2 in both diabetic organs. These findings were in agreement with the angiogenesis histological assays. Fibrosis was augmented in both organs in diabetic as compared to healthy animals.
Altogether, our findings indicate, for the first time, that T1DM heart and kidney ECs present opposite metabolic cues, which are accompanied by distinct angiogenic patterns. These findings enable the development of innovative organ-specific therapeutic strategies targeting diabetic-associated vascular disorders.
背景/目的：血管并发症是导致糖尿病患者出现高发病率和高死亡率的重要因素。尽管已知糖尿病患者的肾脏和心脏存在血管生成失衡的情况，但这种血管生成悖论背后的机制仍不清楚。在本研究中，我们检测了从1型糖尿病（T1DM）小鼠模型中分离出的内皮细胞（ECs）的血管生成和代谢基因表达谱（GEP）。
从健康小鼠和经链脲佐菌素（STZ）处理的小鼠的肾脏和心脏中分离出ECs。然后提取RNA用于分子研究。通过微阵列检测84个血管生成相关基因和84个AMP激活蛋白激酶（AMPK）依赖性基因的GEP。实时PCR证实了显著改变的基因中观察到的变化。通过免疫组织化学分析微血管密度（MVD），通过天狼星红组织学染色评估纤维化，并通过ELISA定量结缔组织生长因子（CTGF）。
T1DM动物肾脏中ECs的相对百分比和MVD增加，而糖尿病小鼠心脏中则观察到相反的趋势。因此，这些动物的肾脏中大多数与AMPK相关的基因上调，而心脏中则下调。血管生成GEP显示，在两个糖尿病器官中，转化生长因子β（Tgfβ）、Notch信号通路和金属蛋白酶组织抑制因子2（Timp2）存在显著差异。这些发现与血管生成组织学检测结果一致。与健康动物相比，糖尿病动物的两个器官中的纤维化均加重。
总之，我们的研究结果首次表明，T1DM心脏和肾脏的ECs呈现相反代谢信号，并伴有不同的血管生成模式。这些发现有助于开发针对糖尿病相关血管疾病的创新性器官特异性治疗策略。
