Evaluation of insulin sensitivity in mice using 13C-glucose labeled clamp technique
10.16352/j.issn.1001-6325.2025.04.0442
- VernacularTitle:13C-葡萄糖钳夹实验评估小鼠胰岛素敏感性
- Author:
Kexin CAO
1
;
Zhuohang LIU
;
Yishen JIANG
;
Xu SUN
;
Jie CHEN
Author Information
1. 中国医学科学院基础医学研究所 北京协和医学院基础学院 重大疾病共性机制研究全国重点实验室免疫学系,北京 100005
- Keywords:
insulin resistance;
glucose clamp experiment;
jugular vein catheterization surgery;
D-glucose-13C6
- From:
Basic & Clinical Medicine
2025;45(4):442-449
- CountryChina
- Language:Chinese
-
Abstract:
Objective To establish a 13C isotope-labeled hyperinsulinemic-euglycemic clamp model for the assessment of insulin sensitivity in mice.Methods The mouse model of insulin resistance was established by high-fat diet feeding.The phosphorylation level of downstream insulin signaling protein,Protein Kinase,also known as Akt was assessed.Glucose metabolism was evaluated using glucose tolerance test,insulin tolerance test,and pyruvate tol-erance tests and the area under the curve of the respective testes over 2 hours was calculated to quantify overall blood glucose level.Mice underwent jugular vein catheterization surgery,and a 13C isotope-labeled hyperinsulinemic-eugly-cemic clamp experiment was conducted to monitor blood glucose levels and to calculate the glucose infusion rate(GIR).Tail vein serum was collected for liquid chromatography-tandem mass spectrometry(LC-MS/MS)analysis to determine glucose disposal rate(GDR)and hepatic gluconeogenesis rate(HGP).Following the inhibition of glycog-enolysis in mice,Akt phosphorylation level was measured to evaluate insulin signaling.The clamp test was repeated to calculate GIR,and tail vein blood serum was analyzed by LC-MS/MS to determine GDR and HGP.Results After one week of high-fat diet feeding,mice exhibited significantly elevated blood glucose level(P＜0.001)accompanied by reduced p-Akt level in liver and muscle.Glucose tolerance tests,insulin tolerance tests and pyruvate tolerance test demonstrated a significant increase in blood glucose level(P＜0.05)and a higher area under curves(AUC)(P＜0.001)in high-fat-fed mice.During the 13C-labeled hyperinsulinemic-euglycemic clamp experiment,after the blood glucose levels were stable,the GIR of high-fat-fed mice was significantly reduced(P＜0.001),GDR was de-creased(P＜0.0001)and hepatic gluconeogenesis rate was increased(P＜0.01).After pharmacological inhibition of glycogenolysis,mice showed elevated blood glucose level(P＜0.001)and further reductions in p-Akt level in liver and muscle.The 13C-labeled clamp experiment revealed that in the treated group,the GIR decreased(P＜0.01)while GDR was reduced(P＜0.000 1)and HGP increased(P＜0.01).Conclusions An improved hyperinsulinemic-eugly-cemic clamp model was developed to assess insulin sensitivity in mice.
