上海交通大学学报(医学版)

• 论著(基础研究) • 上一篇    下一篇

尼克酰胺抑制PKC-βⅡ活性改善高糖导致的心肌微血管内皮细胞血管形成障碍

闫美灵,王法斌*,陈衎恺,李京波,魏 盟   

  1. 上海交通大学附属第六人民医院心内科, 上海 200233
  • 出版日期:2014-08-28 发布日期:2014-09-02
  • 通讯作者: 李京波, 电子信箱: ljbsjtu6h@hotmail.com。
  • 作者简介:闫美灵(1990—), 女, 硕士生; 电子信箱: yanmeiling0622@sina.com; 王法斌(1983—), 男, 硕士生; 电子信箱: wangfabin_2006@163.com。*为共同第一作者。
  • 基金资助:

    上海市科委基金(11ZR1427200)

Inhibition of PKC-βⅡ activity and amelioration of high glucose-induced angiogenesis impairment of cardiac microvasculature by nicotinamide

YAN Mei-ling, WANG Fa-bin*, CHEN Kan-kai, LI Jing-bo, WEI Meng   

  1. Department of Cardiology, the Sixth People's Hospital, Shanghai Jiao Tong University, Shanghai 200233, China
  • Online:2014-08-28 Published:2014-09-02
  • Supported by:

    Foundation of Science and Technology Commission of Shanghai Municipality, 11ZR1427200

摘要:

目的 探讨尼克酰胺对高糖导致的微血管生成障碍的影响及可能机制。方法 将原代心肌微血管内皮细胞分为正常糖组(NG,5.6 mmol/L)、高糖组(HG,33.3
mmol/L)、高糖+尼克酰胺组(HG+N,33.3 mmol/L+20 mmol)和高糖+蛋白激酶C-βⅡ(PKC-βⅡ)抑制剂LY333531组(HG+LY,33.3 mmol/L+20 nmol),培养24 h后分别观察细胞的管腔形成、迁移及增殖情况。Western blotting检测不同组细胞PKC-βⅡ、Akt和内皮型一氧化氮合酶(eNOS)的表达情况。结果 与NG组相比,HG组细胞的管腔形成、迁移和增殖能力明显降低(P<0.05);而HG+N组和HG+LY组细胞的管腔形成、迁移和增殖能力得到明显改善。Western blotting 结果显示:与NG组相比,HG组PKC-βⅡ磷酸化程度上调,且伴随Aktser473及eNOSser1117表达水平的降低(P<0.05)。尼克酰胺不仅抑制了高糖导致的PKC-βⅡ磷酸化程度上调,并且恢复Akt、eNOS磷酸化至NG组水平(P<0.05)。结论 高糖导致了PKC-βⅡ的激活,进而抑制Akt/eNOS通路的活性,从而阻碍了微血管细胞的血管形成。尼克酰胺抑制了高糖条件下PKC-βⅡ的磷酸化,上调Akt/eNOS通路活性,从而改善微血管形成障碍。

关键词: 内皮细胞, 血管生成, 尼克酰胺, 蛋白激酶C

Abstract:

Objective To explore the effects of nicotinamide on the angiogenesis impairment of microvasculature caused by high glucose and the possible mechanisms. Methods Primary cardiac microvascular endothelial cells (CMECs) were divided into the normal glucose group (NG group, 5.6 mmol/L), high glucose group (HG group, 33.3 mmol/L), high glucose+nicotinamide group (HG+N group, 33.3 mmol/L+20 mmol), and high glucose+LY333531, protein kinase C-βⅡ (PKC-βⅡ)
inhibitor, group (HG+LY group, 33.3 mmol/L+20 nmol). Lumen formation, migration, and proliferation of cells were observed after being cultured for 24 h. The expressions of PKC-βⅡ, Akt, and endothelial nitric oxide synthase (eNOS) of cells were detected by the Western blotting. Results Compared to the NG group, the ability of lumen formation, migration, and proliferation of cells of the HG group was significantly lower (P<0.05), while the ability of lumen formation, migration, and proliferation of cells of the HG+N group and HG+LY group was significantly improved. The results of Western blotting showed that compared to the NG group, the phosphorylation level of PKC-βⅡ of the HG group increased and the expressions of protein kinase B (Aktser473) and eNOSser1117 decreased (P<0.05). Nicotinamide not only inhibited the phosphorylation of PKC-βⅡ caused by high glucose, but also recovered the phosphorylation of Akt and eNOS to the level of the NG group (P<0.05). Conclusion The glucose of high concentration activates PKC-βⅡ, inhibits the activity of Akt/eNOS signaling pathway, and prevents the microvascular angiogenesis. Nicotinamide can inhibit the phosphorylation of PKC-βⅡ under high glucose condition, increase the activity of Akt/eNOS signaling pathway, and ameliorate the microvascular angiogenesis impairment.

Key words: endothelial cells, angiogenesis, nicotinamide, protein kinase C