GPR92 activation in islet macrophages controls β cell function in a diet-induced obesity model

Area of Science:

• Metabolic disease research
• Immunology
• Endocrinology

Background:

• Obesity leads to increased pancreatic beta cell mass and dysfunction.
• The role of specific molecular pathways, like GPR92 in islet macrophages, remains unclear.
• Dietary interventions impact metabolic tissues and inflammatory responses.

Purpose of the Study:

• To investigate the function of GPR92 in islet macrophages.
• To determine GPR92's role in high-fat diet-induced obesity and associated inflammation.
• To explore GPR92 as a potential therapeutic target for diabetes.

Main Methods:

• Utilized a high-fat diet-induced (HFD) obese mouse model.
• Compared wild-type (WT) mice with GPR92-knockout (KO) mice.
• Administered GPR92 agonist farnesyl pyrophosphate.

Main Results:

• GPR92-KO mice showed glucose intolerance, reduced insulin, enlarged islets, and increased islet inflammation.
• Lack of GPR92 in macrophages impairs beta cell function and glucose homeostasis.
• GPR92 agonist treatment inhibited HFD-induced islet inflammation and improved insulin secretion in WT mice.

Conclusions:

• GPR92 in islet macrophages is essential for maintaining beta cell function and preventing inflammation.
• GPR92 deficiency exacerbates obesity-induced beta cell dysfunction and diabetes progression.
• Targeting GPR92 presents a promising therapeutic avenue for managing diabetes by reducing islet inflammation.