ErbB3 is required for hyperaminoacidemia-induced pancreatic α cell hyperplasia
Qi Kang1, Jianxin Jia1, E Danielle Dean2
1School of Pharmaceutical Sciences and School of Life Sciences, Xiamen University, Xiamen, China; Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, China.
The Journal of Biological Chemistry
|June 29, 2024
Summary
Elevated blood amino acids trigger pancreatic alpha cell growth. This study reveals that ErbB3 signaling is essential for this alpha cell hyperplasia, uncovering a new regulator in amino acid homeostasis.
Area of Science:
- Endocrinology
- Cell Biology
- Metabolic Regulation
Background:
- Pancreatic alpha cells regulate blood amino acid levels via glucagon secretion.
- Disrupted glucagon signaling causes hyperaminoacidemia, leading to alpha cell hyperplasia.
- The precise mechanisms driving hyperaminoacidemia-induced alpha cell hyperplasia are not fully understood.
Purpose of the Study:
- To investigate the molecular mechanisms underlying alpha cell hyperplasia in response to hyperaminoacidemia.
- To identify novel signaling pathways involved in regulating alpha cell proliferation.
Main Methods:
- Utilized a mouse alpha cell line for in vitro studies.
- Conducted in vivo experiments in zebrafish and mice.
- Investigated the role of ErbB3 signaling and its downstream effectors.
Main Results:
- Hyperaminoacidemia-induced alpha cell hyperplasia is dependent on ErbB3 signaling.
- Signal transducer and activator of transcription 3 (STAT3), a downstream effector of ErbB3, is also implicated.
- ErbB3, potentially partnering with ErbB2, modulates cyclin D2 and p27 expression via mTORC1 and STAT3.
Conclusions:
- ErbB3 is identified as a novel regulator of hyperaminoacidemia-induced alpha cell proliferation.
- ErbB3 signaling is a critical component of the liver-alpha cell axis in aminoacidemia regulation.
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