Department of Nutrition and Integrative Physiology, College of Health, University of Utah, Salt Lake City, UT 84112, USA.
Departments of Biology, Bioengineering, & Medicinal Chemistry, University of Utah, Salt Lake City, UT 84112, USA.
Int J Cardiol. 2018 Jun 15;261:155-158. doi: 10.1016/j.ijcard.2018.03.027. Epub 2018 Mar 8.
Glycosaminoglycan (GAG), a major component of the endothelial glycocalyx, is severely perturbed in diabetic vasculature leading to endothelial inflammation and vascular disease in diabetes. We tested the hypothesis that blueberry metabolites (BBM) ameliorate endothelial inflammation in diabetic endothelial cells (ECs) by restoring cell surface GAGs.
ECs isolated from healthy individuals [human aortic ECs (HAECs)] and diabetic patients (diabetic HAECs) were treated with ±BBM (benzoic acid-4-sulfate, hippuric acid, hydroxyhippuric acid, isovanillic acid-3-sulfate, and vanillic acid-4-sulfate at concentrations known to circulate in human plasma following blueberry consumption) for 3 days, and indices for endothelial inflammation were measured. To analyze GAGs, ECs were incubated with sulfate-free medium supplemented with [S] NaSO ± BBM. Total GAGs in ECs and medium were purified using DEAE-Sepharose column and were analyzed with high-pressure liquid chromatography coupled to an inline flow scintillation analyzer. Heparan sulfate/chondroitin sulfate ratio and disaccharide composition of GAGs from the medium were analyzed using DEAE-3SW column and Dionex CarboPac PA1 column, respectively.
BBM suppressed diabetes-induced monocyte binding to ECs, and reduced the expression of inflammatory markers in diabetic HAECs. Diabetic HAECs displayed a decrease in [S] sulfate incorporation into the cell surface GAGs indicating the dysregulation of sulfated GAGs. However, treatment with BBM restored the levels of GAGs in diabetic HAECs. The composition, heparan sulfate/chondroitin sulfate ratio, and disaccharide composition of GAGs from medium were similar among groups.
BBM restored cell surface GAGs and attenuated endothelial inflammation in diabetic HAECs. Blueberry might complement conventional therapies to improve vascular complications in diabetes.
糖胺聚糖（GAG）是内皮糖萼的主要成分，在糖尿病血管中严重受到干扰，导致内皮炎症和糖尿病血管疾病。我们检验了这样一个假设，即蓝莓代谢物（BBM）通过恢复细胞表面 GAG 来改善糖尿病内皮细胞（EC）中的内皮炎症。
用 ±BBM（苯磺酸-4-硫酸盐、马尿酸、羟基马尿酸、香草酸-3-硫酸盐和香草酸-4-硫酸盐，浓度为已知在人类食用蓝莓后在血浆中循环）处理来自健康个体（人主动脉内皮细胞 [HAEC]）和糖尿病患者（糖尿病 HAEC）的 EC3 天，并测量内皮炎症的指标。为了分析 GAG，用不含硫酸盐的培养基孵育 EC，补充 [S] NaSO4 ± BBM。用 DEAE-Sepharose 柱纯化 EC 中的总 GAG 和培养基中的 GAG，并用高压液相色谱法与在线流闪烁分析器联用进行分析。用 DEAE-3SW 柱和 Dionex CarboPac PA1 柱分别分析培养基中 GAG 的硫酸乙酰肝素/硫酸软骨素比值和二糖组成。
BBM 抑制了糖尿病诱导的单核细胞与 EC 的结合，并降低了糖尿病 HAEC 中炎症标志物的表达。糖尿病 HAEC 显示细胞表面 GAG 中 [S]硫酸盐掺入减少，表明硫酸化 GAG 失调。然而，用 BBM 处理可恢复糖尿病 HAEC 中 GAG 的水平。各组培养基中 GAG 的组成、硫酸乙酰肝素/硫酸软骨素比值和二糖组成相似。
BBM 恢复了糖尿病 HAEC 中的细胞表面 GAG 并减轻了内皮炎症。蓝莓可能与常规疗法互补，以改善糖尿病的血管并发症。
