GALNT4 primes monocytes adhesion and transmigration by regulating O-Glycosylation of PSGL-1 in atherosclerosis
GALNT4 primes monocytes adhesion and transmigration by regulating O-Glycosylation of PSGL-1 in atherosclerosis
复制标题
GALNT4 通过调节动脉粥样硬化中 PSGL-1 的 O-糖基化来启动单核细胞粘附和迁移
DOI：
10.1016/j.yjmcc.2021.12.012
复制
发表时间：
2022-01-05
影响因子：
5
通讯作者：
Huang, Rongchong
中科院分区：
文献类型：
--
作者：
Ye, Zhishuai;Guo, Hongzhou;Huang, Rongchong
动脉粥样硬化是心血管疾病的主要潜在原因。全基因组关联研究表明，负责启动粘蛋白型O-糖基化的GalNAc-T4（GALNT 4）在心血管疾病的易感性中起重要作用，但其确切机制尚不清楚。因此，我们试图确定GALNT 4在动脉粥样硬化中的作用和机制。首先，我们通过免疫组化发现随着ApoE（-/-）小鼠动脉粥样硬化的进展，斑块中GALNT 4的表达和蛋白O-糖基化均增加。体外用ACS（急性冠状动脉综合征）血清处理并经受LPS和ox-LDL的人单核细胞中GALNT 4的表达也增加。此外，通过shRNA慢病毒沉默GALNT 4的表达减轻了ApoE（-/-）小鼠中动脉粥样硬化斑块的形成和单核细胞/巨噬细胞浸润。功能研究表明，GALNT 4敲低抑制P-选择素诱导的单核细胞表面β 2整合素的活化，降低单核细胞在P-选择素刺激的流动条件下的粘附，以及抑制单核细胞趋化蛋白-1（MCP-1）触发的单核细胞迁移。相反，GALNT 4过表达增强单核细胞粘附和迁移。此外，野豌豆凝集素（VVL）下拉和PSGL-1免疫沉淀分析显示，GALNT 4过表达增加PSGL-1的O-糖基化，并且P-选择素诱导单核细胞上Akt/ mTOR和I kappa B α/NF kappa B的磷酸化。相反，GALNT 4的敲低降低了VVL结合并减弱了Akt/mTOR和I κ B α/NF κ B的活化。此外，mTOR抑制剂雷帕霉素阻断了GALNT 4过表达对单核细胞的这些影响。总之，GALNT 4催化PSGL-10-糖基化，其参与P-选择素通过Akt/mTOR和NF κ B途径诱导单核细胞粘附和迁移。因此，GALNT 4可能是动脉粥样硬化的潜在治疗靶点。
Atherosclerosis is a major underlying cause of cardiovascular disease. Genome wide association studies have predicted that GalNAc-T4 (GALNT4), which responsible for initiating step of mucin-type O-glycosylation, plays a causal role in the susceptibility to cardiovascular diseases, whereas the precise mechanism remains obscure. Thus, we sought to determine the role and mechanism of GALNT4 in atherosclerosis. Firstly, we found the expression of GALNT4 and protein O-glycosylation were both increased in plaque as atherosclerosis progressed in ApoE(-/-) mice by immunohistochemistry. And the expression of GALNT4 was also increased in human monocytes treated with ACS (acute coronary syndrome) sera and subjected to LPS and ox-LDL in vitro. Moreover, silencing expression of GALNT4 by shRNA lentivirus alleviated atherosclerotic plaque formation and monocyte/macrophage infiltration in ApoE(-/-) mice. Functional investigations demonstrate that GALNT4 knockdown inhibited Pselectin-induced activation of beta 2 integrin on the surface of monocytes, decreased monocytes adhesion under flow condition with P-selectin stimulation, as well as suppressed monocytes transmigration triggered by monocyte chemotactic protein-1(MCP-1). In contrast, GALNT4 overexpression enhanced monocytes adhesion and transmigration. Furthermore, Vicia Villosa Lectin (VVL) pull down and PSGL-1 immunoprecipitation assays showed that GALNT4 overexpression increased O-Glycosylation of PSGL-1 and P-selectin induce phosphorylation of Akt/ mTOR and I kappa B alpha/NF kappa B on monocytes. Conversely, knockdown of GALNT4 decreased VVL binding and attenuated the activation of Akt/mTOR and I kappa B alpha/NF kappa B. Additionally, mTOR inhibitor rapamycin blocked these effects of GALNT4 overexpression on monocytes. Collectively, GALNT4 catalyzed PSGL-1 O-glycosylation that involved in P-selectin induced monocytes adhesion and transmigration via Akt/mTOR and NF kappa B pathway. Thus, GALNT4 may be a potential therapeutic target for atherosclerosis.