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Yuan H, Kang Q, Li Z, Bai X, Jia J, Han D, Wu X, Li M. Crispr-Cas9 mediated complete deletion of glucagon receptor in mice display hyperglucagonemia and α-cell hyperplasia. Biochem Biophys Res Commun 2023; 643:121-128. [PMID: 36596263 DOI: 10.1016/j.bbrc.2022.12.079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 12/27/2022] [Indexed: 12/29/2022]
Abstract
Glucagon receptor plays an important role in the regulation of glucose metabolism. Studies have revealed that glucagon receptor antagonism is a potential effective treatment for diabetes. However, the functions of GCGR have not been fully illustrated. Although two Gcgr truncation knockout mice models have been widely used for GCGR function studies, truncated gene may remain neomorphic and/or dominant-negative function. In this study, we took the advantages of Crispr-Cas9 technique and generated a novel allele of GCGR in the mouse that yields complete loss of GCGR protein. Our studies reveal that complete deletion of Gcgr results in hyperglucagonemia, α-cell hyperplasia, improvement of glucose tolerance. These results are similar to the Gcgr-truncated mutation in mice. Hence, we provide a novel strain of GCGR knockout mice for the GCGR function studies.
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Affiliation(s)
- Hang Yuan
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, 361102, China; Department of Cardiac Surgery, The Xiamen Cardiovascular Hospital of Xiamen University, Xiamen, 361016, China
| | - Qi Kang
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, 361102, China; State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, 361102, China
| | - Zhehui Li
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, 361102, China
| | - Xuanxuan Bai
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, 361102, China; School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Jianxin Jia
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, 361102, China; State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, 361102, China
| | - Daxiong Han
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, 361102, China
| | - Xijie Wu
- Department of Cardiac Surgery, The Xiamen Cardiovascular Hospital of Xiamen University, Xiamen, 361016, China.
| | - Mingyu Li
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, 361102, China; Key Laboratory of Tropical Marine Ecosystem and Bioresource, Fourth Institute of Oceanography, Ministry of Natural Resources, Beihai, 536007, China.
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Ng XW, Chung YH, Piston DW. Intercellular Communication in the Islet of Langerhans in Health and Disease. Compr Physiol 2021; 11:2191-2225. [PMID: 34190340 DOI: 10.1002/cphy.c200026] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Blood glucose homeostasis requires proper function of pancreatic islets, which secrete insulin, glucagon, and somatostatin from the β-, α-, and δ-cells, respectively. Each islet cell type is equipped with intrinsic mechanisms for glucose sensing and secretory actions, but these intrinsic mechanisms alone cannot explain the observed secretory profiles from intact islets. Regulation of secretion involves interconnected mechanisms among and between islet cell types. Islet cells lose their normal functional signatures and secretory behaviors upon dispersal as compared to intact islets and in vivo. In dispersed islet cells, the glucose response of insulin secretion is attenuated from that seen from whole islets, coordinated oscillations in membrane potential and intracellular Ca2+ activity, as well as the two-phase insulin secretion profile, are missing, and glucagon secretion displays higher basal secretion profile and a reverse glucose-dependent response from that of intact islets. These observations highlight the critical roles of intercellular communication within the pancreatic islet, and how these communication pathways are crucial for proper hormonal and nonhormonal secretion and glucose homeostasis. Further, misregulated secretions of islet secretory products that arise from defective intercellular islet communication are implicated in diabetes. Intercellular communication within the islet environment comprises multiple mechanisms, including electrical synapses from gap junctional coupling, paracrine interactions among neighboring cells, and direct cell-to-cell contacts in the form of juxtacrine signaling. In this article, we describe the various mechanisms that contribute to proper islet function for each islet cell type and how intercellular islet communications are coordinated among the same and different islet cell types. © 2021 American Physiological Society. Compr Physiol 11:2191-2225, 2021.
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Affiliation(s)
- Xue W Ng
- Department of Cell Biology and Physiology, Washington University, St Louis, Missouri, USA
| | - Yong H Chung
- Department of Cell Biology and Physiology, Washington University, St Louis, Missouri, USA
| | - David W Piston
- Department of Cell Biology and Physiology, Washington University, St Louis, Missouri, USA
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