Alghamdi Farah, Guo Merry, Abdulkhalek Samar, Crawford Nicola, Amith Schammim Ray, Szewczuk Myron R
Department of Biomedical & Molecular Sciences, Queen's University, Kingston, Ontario K7L 3N6, Canada.
Cell Signal. 2014 Jun;26(6):1355-68. doi: 10.1016/j.cellsig.2014.02.015. Epub 2014 Feb 28.
Insulin-induced insulin receptor (IR) tyrosine kinase activation and insulin cell survival responses have been reported to be under the regulation of a membrane associated mammalian neuraminidase-1 (Neu1). The molecular mechanism(s) behind this process is unknown. Here, we uncover a novel Neu1 and matrix metalloproteinase-9 (MMP-9) cross-talk in alliance with neuromedin B G-protein coupled receptor (GPCR), which is essential for insulin-induced IR activation and cellular signaling. Neu1, MMP-9 and neuromedin B GPCR form a complex with IRβ subunit on the cell surface. Oseltamivir phosphate (Tamiflu®), anti-Neu1 antibodies, broad range MMP inhibitors piperazine and galardin (GM6001), MMP-9 specific inhibitor (MMP-9i), and GPCR neuromedin B specific antagonist BIM-23127 dose-dependently inhibited Neu1 activity associated with insulin stimulated rat hepatoma cells (HTCs) that overly express human IRs (HTC-IR). Tamiflu, anti-Neu1 antibodies and MMP-9i attenuated phosphorylation of IRβ and insulin receptor substrate-1 (IRS1) associated with insulin-stimulated cells. Olanzapine, an antipsychotic agent associated with insulin resistance, induced Neu3 sialidase activity in WG544 or 1140F01 human sialidosis fibroblast cells genetically defective in Neu1. Neu3 antagonist 2-deoxy-2,3-didehydro-N-acetylneuraminic acid (DANA) and anti-Neu3 antibodies inhibited sialidase activity associated with olanzapine treated murine Neu4 knockout macrophage cells. Olanzapine attenuated phosphorylation of IGF-R and IRS1 associated with insulin-stimulated human wild-type fibroblast cells. Our findings identify a novel insulin receptor-signaling platform that is critically essential for insulin-induced IRβ tyrosine kinase activation and cellular signaling. Olanzapine-induced Neu3 sialidase activity attenuated insulin-induced IGF-R and IRS1 phosphorylation contributing to insulin resistance.
据报道，胰岛素诱导的胰岛素受体（IR）酪氨酸激酶激活和胰岛素细胞存活反应受膜相关的哺乳动物神经氨酸酶-1（Neu1）调控。这一过程背后的分子机制尚不清楚。在此，我们发现了一种与神经介素B G蛋白偶联受体（GPCR）相关的新型Neu1和基质金属蛋白酶-9（MMP-9）相互作用，这对于胰岛素诱导的IR激活和细胞信号传导至关重要。Neu1、MMP-9和神经介素B GPCR在细胞表面与IRβ亚基形成复合物。磷酸奥司他韦（达菲®）、抗Neu1抗体、广谱MMP抑制剂哌嗪和加拉迪宁（GM6001）、MMP-9特异性抑制剂（MMP-9i）以及GPCR神经介素B特异性拮抗剂BIM-23127均剂量依赖性地抑制与胰岛素刺激的过度表达人IRs的大鼠肝癌细胞（HTC-IR）相关的Neu1活性。达菲、抗Neu1抗体和MMP-9i减弱了与胰岛素刺激细胞相关的IRβ和胰岛素受体底物-1（IRS1）的磷酸化。奥氮平是一种与胰岛素抵抗相关的抗精神病药物，在Neu1基因缺陷的WG544或1140F01人涎酸沉积症成纤维细胞中诱导Neu3唾液酸酶活性。Neu3拮抗剂2-脱氧-2,,3-二脱氢-N-乙酰神经氨酸（DANA）和抗Neu3抗体抑制与奥氮平处理的小鼠Neu4基因敲除巨噬细胞相关的唾液酸酶活性。奥氮平减弱了与胰岛素刺激的人野生型成纤维细胞相关的IGF-R和IRS1的磷酸化。我们的研究结果确定了一个新型的胰岛素受体信号平台，该平台对于胰岛素诱导的IRβ酪氨酸激酶激活和细胞信号传导至关重要。奥氮平诱导的Neu3唾液酸酶活性减弱了胰岛素诱导的IGF-R和IRS1磷酸化，导致胰岛素抵抗。
