Lai Fenghua, Chen Yan, Lin Huimei, Wang Xuelan, Zhu Xiaonan, Li Yanbing, Xiao Haipeng, Cao Xiaopei
Department of Endocrinology, First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan 2nd Rd., Guangzhou, 510080, People's Republic of China.
Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, 74 Zhongshan 2nd Rd., Guangzhou, 510080, People's Republic of China.
Mol Cell Endocrinol. 2017 Sep 5;452:110-119. doi: 10.1016/j.mce.2017.05.021. Epub 2017 May 24.
Pancreatic-derived factor (PANDER) is a pancreatic islet-specific cytokine that co-secretes with insulin. However, its biological function remains largely unknown. We have recently shown that the intestine might be its novel target tissue. The aim of this study was to clarify whether PANDER impacts the production of glucagon-like peptide-1 (GLP-1).
We treated GLUTag cells from the mouse intestine L cell line with recombinant PANDER protein and hepatic overexpression of PANDER in an obese murine model.
In GLUTag cells, PANDER exposure led to decreased proglucagon gene mRNA expression and GLP-1 secretion without affecting cell viability or caspase-3 activation. Overexpression of PANDER in mice induced glucose intolerance and impaired glucose-stimulated GLP-1 secretion Moreover, PANDER blocked insulin-induced GLP-1 secretion by inhibiting the insulin signalling-Wnt pathway and directly inhibited the cAMP/PKA pathway.
Our findings indicate that intestinal L cells are responsive to PANDER, and elevated PANDER levels impair GLP-1 production in vitro and in vivo.
胰腺衍生因子(PANDER)是一种与胰岛素共同分泌的胰岛特异性细胞因子。然而,其生物学功能仍 largely 未知。我们最近发现肠道可能是其新的靶组织。本研究的目的是阐明 PANDER 是否影响胰高血糖素样肽 -1(GLP-1)的产生。
我们用重组 PANDER 蛋白处理来自小鼠肠道 L 细胞系的 GLUTag 细胞,并在肥胖小鼠模型中进行肝脏 PANDER 的过表达。
在 GLUTag 细胞中,PANDER 处理导致胰高血糖素原基因 mRNA 表达降低和 GLP-1 分泌减少,而不影响细胞活力或半胱天冬酶 -3 激活。小鼠中 PANDER 的过表达诱导葡萄糖不耐受并损害葡萄糖刺激的 GLP-1 分泌。此外,PANDER 通过抑制胰岛素信号 -Wnt 途径阻断胰岛素诱导的 GLP-1 分泌,并直接抑制 cAMP/PKA 途径。
我们的研究结果表明肠道 L 细胞对 PANDER 有反应,并且升高的 PANDER 水平在体外和体内损害 GLP-1 的产生。