Profile of the bile acid FXR-FGF15 pathway in the glucolipid metabolism disorder of diabetic mice suffering from chronic stress

Weijia Cai; Canye Li; Zuanjun Su; Jinming Cao; Zhicong Chen; Yitian Chen; Zhijun Guo; Jian Cai; Feng Xu

doi:10.7717/peerj.16407

Profile of the bile acid FXR-FGF15 pathway in the glucolipid metabolism disorder of diabetic mice suffering from chronic stress

PeerJ. 2023 Nov 15:11:e16407. doi: 10.7717/peerj.16407. eCollection 2023.

Authors

Weijia Cai^{1

2}, Canye Li^{1

2}, Zuanjun Su^{1

2}, Jinming Cao^{1

2}, Zhicong Chen^{1

2}, Yitian Chen^{1

2}, Zhijun Guo³, Jian Cai⁴, Feng Xu^{1

5}

Affiliations

¹ Fengxian Hospital, Southern Medical University, Shanghai, China.
² School of Pharmaceutical Science, Southern Medical University, Guangzhou, China.
³ Heyou Meihe Hospital, Foshan, Guangdong, China.
⁴ Fengxian Mental Health Center, Shanghai, China.
⁵ Sixth People' s Hospital South Campus, Shanghai Jiaotong University, Shanghai, China.

Abstract

Background: Imbalances in bile acid (BA) synthesis and metabolism are involved in the onset of diabetes and depression in humans and rodents. However, the role of BAs and the farnesoid X receptor (FXR)/fibroblast growth factor (FGF) 15 signaling pathway in the development of diabetes and depression is still largely unknown. Therefore, we investigated the potential molecular mechanisms of BAs that may be associated with glucolipid metabolism disorders in diabetic mice subjected to chronic stress.

Methods: The type 2 diabetes mellitus (T2DM) mouse model was induced by feeding mice a high-fat diet and administering an intraperitoneal injection of streptozotocin (STZ). The chronic unpredictable mild stress (CUMS) procedure was performed by introducing a series of mild stressors. Forty mice were randomly divided into the regular chow feeding group and the high-fat diet feeding group. After two weeks of feeding, the mice were randomly divided into four groups: the Control group, CUMS group, T2DM group, and T2DM+CUMS group. The T2DM group and T2DM+CUMS group received an intraperitoneal injection of STZ to induce the T2DM model. The CUMS and T2DM+CUMS groups were exposed to CUMS to induce depressive-like phenotypes. Blood and tissue samples were obtained for pertinent analysis and detection.

Results: Compared with the T2DM mice, T2DM+CUMS mice had higher blood glucose and lipid levels, insulin resistance, inflammation of the liver and pancreas, impaired liver function, and increased total bile acids. These changes were accompanied by attenuated FXR signaling. Chronic stress was found to attenuate FXR expression and its downstream target, FGF15, in the ileum when compared with the T2DM group.

Conclusion: FXR may play a role in the diabetic disorder of glucolipid metabolism when aggravated by chronic stress. FXR and its downstream target, FGF15, may be therapeutic targets for treating comorbid T2DM and depression.

Keywords: Bile acids; Depression; FGF15; FXR; Glucolipid metabolism; High fed diet; Insulin; Streptozotocin.

MeSH terms

Animals
Bile Acids and Salts
Diabetes Mellitus, Experimental* / metabolism
Diabetes Mellitus, Type 2* / complications
Humans
Liver Diseases*
Mice

Substances

Bile Acids and Salts

Grants and funding

This work was supported by the Shanghai Municipal Science Commission (grant number 19411971700). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.