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Updated: Jun 6, 2026
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High-resolution Respirometry to Measure Mitochondrial Function of Intact Beta Cells in the Presence of Natural Compounds
Published on: January 23, 2018
Neuregulin 4-dependent MAPK amplification mediates urate-induced β-cell dysfunction
Yunyang Wang1,2, Kun Zhang3, Zhiyuan Li4
1Department of Endocrinology and Metabolism, The Affiliated Hospital of Qingdao University, Qingdao, China.
Journal of Diabetes Investigation
|June 5, 2026
Summary
High uric acid levels disrupt glucose homeostasis and cause pancreatic beta-cell apoptosis through neuregulin-4 (Nrg4) and MAPK signaling.
Area of Science:
- Endocrinology
- Metabolic Research
- Molecular Biology
Background:
- Clinical studies suggest a link between hyperuricemia (HU) and diabetes.
- The exact role of serum urate in glucose metabolism remains unclear.
- Novel spontaneous HU mouse models are needed to investigate these mechanisms.
Purpose of the Study:
- To characterize glucose metabolism in a novel spontaneous HU mouse model.
- To elucidate the molecular mechanisms underlying HU's impact on glucose metabolism.
- To identify key mediators of HU-induced pancreatic beta-cell apoptosis.
Main Methods:
- Generated a Uricase (Uox) gene knockout mouse model for spontaneous HU.
- Analyzed islet microarray data from Uox-KO and wild-type mice to identify apoptosis-related genes.
- Utilized MIN6 cells to assess apoptosis and protein expression via flow cytometry and Western blotting after siRNA transfection.
Main Results:
- Male Uox-KO mice displayed glucose intolerance without insulin resistance.
- Elevated pancreatic beta-cell apoptosis was observed in male Uox-KO mice.
- Neuregulin-4 (Nrg4) was identified as a mediator of HU-induced beta-cell apoptosis, essential for urate-triggered cell death and MAPK activation.
Conclusions:
- Hyperuricemia disrupts glucose homeostasis by inducing pancreatic beta-cell apoptosis.
- Nrg4 upregulation and subsequent MAPK signaling amplification are key mechanisms.
- This study provides molecular insights into the link between HU and impaired glucose metabolism.
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