Gsα-dependent signaling is required for postnatal establishment of a functional β-cell mass.
Gsα-dependent signaling is required for postnatal establishment of a functional β-cell mass.
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DOI：
10.1016/j.molmet.2021.101264
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发表时间：
2021-11
影响因子：
8.1
通讯作者：
Gasa R
中科院分区：
文献类型：
--
作者：
Serra-Navarro B;Fernandez-Ruiz R;García-Alamán A;Pradas-Juni M;Fernandez-Rebollo E;Esteban Y;Mir-Coll J;Mathieu J;Dalle S;Hahn M;Ahlgren U;Weinstein LS;Vidal J;Gomis R;Gasa R
出生后早期是建立功能性β细胞群的关键时期，β细胞群将在一生中维持全身葡萄糖稳态。β细胞在胚胎发育期间由祖细胞形成，但在出生后数量显著增加并达到功能成熟。参与这些过程的信号和途径尚未完全阐明。环腺苷一磷酸（cAMP）是一种细胞内信号分子，已知可调节成人β细胞的胰岛素分泌、基因表达、增殖和存活。异三聚体G蛋白Gs通过激活腺苷酸环化酶刺激camp依赖通路。在这项研究中，我们试图探索gs依赖性信号在出生后β细胞发育中的作用。为了研究Gs依赖的信号传导，我们使用Cre缺失系Ins1Cre从β细胞中去除Gs蛋白的α亚基（Gsα），产生了条件敲除小鼠。小鼠在葡萄糖稳态方面具有特征，包括体内葡萄糖耐量、葡萄糖诱导的胰岛素分泌和胰岛素敏感性。采用组织形态学分析和光学投影断层扫描研究β细胞团。采用ki67和磷酸化组蛋白H3免疫抑制法检测β-细胞增殖，TUNEL法检测细胞凋亡。在离体胰岛和分选β细胞中采用qPCR检测基因表达。利用基于htrf的技术在离体胰岛中研究细胞内cAMP。在离体胰岛中，通过免疫印迹分析这些通路的相关成分来确定cAMP和胰岛素信号通路的激活状态。用BrdU掺入法评估游离胰岛细胞的体外增殖。β细胞中gsa α的消除导致β细胞质量减少，胰岛素分泌不足和严重的葡萄糖耐受不良。这些缺陷在断奶时表现明显，并与出生后β细胞增殖减少、关键β细胞身份和成熟基因表达不足有关。此外，Gsα的缺失导致胰岛素转导通路广泛的多水平破坏，导致胰岛对胰岛素的增殖反应特异性消除。我们得出的结论是，出生后早期β细胞的生长和成熟需要Gsα，并提出这部分是通过其与胰岛素信号的串扰介导的。我们的发现揭示了出生后β细胞中这两种通路之间的紧密联系，这可能意味着使用camp升高剂促进糖尿病中β细胞的再生和成熟。gsa α信号参与了出生后β细胞团的形成。出生后早期β细胞增殖和成熟需要gsa α。Gsα的缺失导致胰岛素/Igf通路的多级破坏。gsa α的缺失会损害β细胞对胰岛素的增殖反应。胰岛中胰岛素受体剪接和蛋白水平的调控。
Early postnatal life is a critical period for the establishment of the functional β-cell mass that will sustain whole-body glucose homeostasis during the lifetime. β cells are formed from progenitors during embryonic development but undergo significant expansion in quantity and attain functional maturity after birth. The signals and pathways involved in these processes are not fully elucidated. Cyclic adenosine monophosphate (cAMP) is an intracellular signaling molecule that is known to regulate insulin secretion, gene expression, proliferation, and survival of adult β cells. The heterotrimeric G protein Gs stimulates the cAMP-dependent pathway by activating adenylyl cyclase. In this study, we sought to explore the role of Gs-dependent signaling in postnatal β-cell development. To study Gs-dependent signaling, we generated conditional knockout mice in which the α subunit of the Gs protein (Gsα) was ablated from β-cells using the Cre deleter line Ins1Cre. Mice were characterized in terms of glucose homeostasis, including in vivo glucose tolerance, glucose-induced insulin secretion, and insulin sensitivity. β-cell mass was studied using histomorphometric analysis and optical projection tomography. β-cell proliferation was studied by ki67 and phospho-histone H3 immunostatining, and apoptosis was assessed by TUNEL assay. Gene expression was determined in isolated islets and sorted β cells by qPCR. Intracellular cAMP was studied in isolated islets using HTRF-based technology. The activation status of the cAMP and insulin-signaling pathways was determined by immunoblot analysis of the relevant components of these pathways in isolated islets. In vitro proliferation of dissociated islet cells was assessed by BrdU incorporation. Elimination of Gsα in β cells led to reduced β-cell mass, deficient insulin secretion, and severe glucose intolerance. These defects were evident by weaning and were associated with decreased proliferation and inadequate expression of key β-cell identity and maturation genes in postnatal β-cells. Additionally, loss of Gsα caused a broad multilevel disruption of the insulin transduction pathway that resulted in the specific abrogation of the islet proliferative response to insulin. We conclude that Gsα is required for β-cell growth and maturation in the early postnatal stage and propose that this is partly mediated via its crosstalk with insulin signaling. Our findings disclose a tight connection between these two pathways in postnatal β cells, which may have implications for using cAMP-raising agents to promote β-cell regeneration and maturation in diabetes. Gsα signaling is involved in postnatal β-cell mass establishment. Gsα is required for β-cell proliferation and maturation during early postnatal life. Loss of Gsα results in multilevel disruption of the insulin/Igf pathway. Loss of of Gsα impairs the β-cell proliferative response to insulin. Gsα signaling regulates insulin receptor splicing and protein levels in islets.
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影响因子：
7.7
作者：
Hang Y;Yamamoto T;Benninger RK;Brissova M;Guo M;Bush W;Piston DW;Powers AC;Magnuson M;Thurmond DC;Stein R
通讯作者：
Stein R
DOI：
10.1073/pnas.0408268102
发表时间：
2005-05-17
影响因子：
11.1
作者：
Chen, M;Gavrilova, O;Weinstein, LS
通讯作者：
Weinstein, LS
影响因子：
7.7
作者：
Hansotia, T;Baggio, LL;Drucker, DJ
通讯作者：
Drucker, DJ
影响因子：
8.2
作者：
Cantley, J.;Choudhury, A. I.;Withers, D. J.
通讯作者：
Withers, D. J.
影响因子：
29
作者：
Andersson O;Adams BA;Yoo D;Ellis GC;Gut P;Anderson RM;German MS;Stainier DY
通讯作者：
Stainier DY