5'-AMP-activated protein kinase plays an essential role in geniposide-regulated glucose-stimulated insulin secretion in rat pancreatic INS-1 β cells.
Our previous work showed that geniposide affected glucose-stimulated insulin secretion (GSIS) via regulating glucose uptake and metabolism in pancreatic β cells; however, the molecular mechanisms remain largely unknown. Substantial evidence suggests that activation of 5'-AMP-activated protein kinase (AMPK) plays a central role in GSIS. Here, we aim to determine the role of AMPK on geniposide-regulated GSIS in rat pancreatic INS-1 cells. The results demonstrated that 6-[4-(2-piperidin-1-yletoxy)-phenyl]-3-pyridin-4-yl-pyrazolo[1,5-α] pyrimidine (Compound C; an AMPK inhibitor) significantly attenuated the effects of geniposide on glucose uptake, energy metabolism, and insulin secretion in INS-1 cells. We also observed that geniposide induced phosphorylation of acetyl-CoA carboxylase (ACC), a marker of AMPK activity, in a time-dependent manner in INS-1 cells; however, in the presence of Compound C, the influence of geniposide on ACC phosphorylation was obviously inhibited. Furthermore, the knockdown of AMPK protein with AMPK siRNA treatment decreased the effects of geniposide on glucose uptake, adenosine triphosphate production, and GSIS. All these data indicate that AMPK plays an essential role in geniposide-regulated GSIS in pancreatic β cells.
Chongqing Key Lab of Medicinal Chemistry and Molecular Pharmacology, Chongqing University of Technology, Chongqing, 400054, China.
Yanan
Y
Hao
Chongqing Key Lab of Medicinal Chemistry and Molecular Pharmacology, Chongqing University of Technology, Chongqing, 400054, China.
Chunyan
C
Liu
Chongqing Key Lab of Medicinal Chemistry and Molecular Pharmacology, Chongqing University of Technology, Chongqing, 400054, China.
Fei
F
Yin
Chongqing Key Lab of Medicinal Chemistry and Molecular Pharmacology, Chongqing University of Technology, Chongqing, 400054, China.
Yonglan
Y
Zhang
Chongqing Key Lab of Medicinal Chemistry and Molecular Pharmacology, Chongqing University of Technology, Chongqing, 400054, China. jhliu@cqut.edu.cn.
Jianhui
J
Liu
D055372:AMP-Activated Protein Kinases / Q000378:metabolism*; D000818:Animals; D005947:Glucose / Q000378:metabolism*; D007328:Insulin; D050417:Insulin-Secreting Cells / Q000378:metabolism*; D039823:Iridoids / Q000378:metabolism*; D051381:Rats; D014162:Transfection
D007328:Insulin; D039823:Iridoids; C007835:geniposide; D055372:AMP-Activated Protein Kinases; D005947:Glucose
5′-AMP-activated protein kinase (AMPK); Acetyl-CoA carboxylase (ACC); Geniposide; Glucose-stimulated insulin secretion (GSIS)