- Diabetes, obesity and metabolism
- Inhibition of Sodium-Glucose Cotransporter-2 during Serum Deprivation Increases Hepatic Gluconeogenesis via the AMPK/AKT/FOXO Signaling Pathway
-
Jinmi Lee, Seok-Woo Hong, Min-Jeong Kim, Yu-Mi Lim, Sun Joon Moon, Hyemi Kwon, Se Eun Park, Eun-Jung Rhee, Won-Young Lee
-
Endocrinol Metab. 2024;39(1):98-108. Published online January 3, 2024
-
DOI: https://doi.org/10.3803/EnM.2023.1786
-
-
 Abstract
 PDF Supplementary Material PubReader  ePub
- Background
Sodium-dependent glucose cotransporter 2 (SGLT2) mediates glucose reabsorption in the renal proximal tubules, and SGLT2 inhibitors are used as therapeutic agents for treating type 2 diabetes mellitus. This study aimed to elucidate the effects and mechanisms of SGLT2 inhibition on hepatic glucose metabolism in both serum deprivation and serum supplementation states.
Methods
Huh7 cells were treated with the SGLT2 inhibitors empagliflozin and dapagliflozin to examine the effect of SGLT2 on hepatic glucose uptake. To examine the modulation of glucose metabolism by SGLT2 inhibition under serum deprivation and serum supplementation conditions, HepG2 cells were transfected with SGLT2 small interfering RNA (siRNA), cultured in serum-free Dulbecco’s modified Eagle’s medium for 16 hours, and then cultured in media supplemented with or without 10% fetal bovine serum for 8 hours.
Results
SGLT2 inhibitors dose-dependently decreased hepatic glucose uptake. Serum deprivation increased the expression levels of the gluconeogenesis genes peroxisome proliferator-activated receptor gamma co-activator 1 alpha (PGC-1α), glucose 6-phosphatase (G6pase), and phosphoenolpyruvate carboxykinase (PEPCK), and their expression levels during serum deprivation were further increased in cells transfected with SGLT2 siRNA. SGLT2 inhibition by siRNA during serum deprivation induces nuclear localization of the transcription factor forkhead box class O 1 (FOXO1), decreases nuclear phosphorylated-AKT (p-AKT), and p-FOXO1 protein expression, and increases phosphorylated-adenosine monophosphate-activated protein kinase (p-AMPK) protein expression. However, treatment with the AMPK inhibitor, compound C, reversed the reduction in the protein expression levels of nuclear p- AKT and p-FOXO1 and decreased the protein expression levels of p-AMPK and PEPCK in cells transfected with SGLT2 siRNA during serum deprivation.
Conclusion
These data show that SGLT2 mediates glucose uptake in hepatocytes and that SGLT2 inhibition during serum deprivation increases gluconeogenesis via the AMPK/AKT/FOXO1 signaling pathway.
- Diabetes, Obesity and Metabolism
- Dulaglutide Ameliorates Palmitic Acid-Induced Hepatic Steatosis by Activating FAM3A Signaling Pathway
-
Jinmi Lee, Seok-Woo Hong, Min-Jeong Kim, Sun Joon Moon, Hyemi Kwon, Se Eun Park, Eun-Jung Rhee, Won-Young Lee
-
Endocrinol Metab. 2022;37(1):74-83. Published online February 9, 2022
-
DOI: https://doi.org/10.3803/EnM.2021.1293
-
-
4,936
View
-
235
Download
-
5
Web of Science
-
5
Crossref
-
Abstract
PDFSupplementary MaterialPubReader ePub
- Background
Dulaglutide, a long-acting glucagon-like peptide-1 receptor agonist (GLP-1RA), has been shown to reduce body weight and liver fat content in patients with type 2 diabetes. Family with sequence similarity 3 member A (FAM3A) plays a vital role in regulating glucose and lipid metabolism. The aim of this study was to determine the mechanisms by which dulaglutide protects against hepatic steatosis in HepG2 cells treated with palmitic acid (PA).
Methods
HepG2 cells were pretreated with 400 μM PA for 24 hours, followed by treatment with or without 100 nM dulaglutide for 24 hours. Hepatic lipid accumulation was determined using Oil red O staining and triglyceride (TG) assay, and the expression of lipid metabolism-associated factor was analyzed using quantitative real time polymerase chain reaction and Western blotting.
Results
Dulaglutide significantly decreased hepatic lipid accumulation and reduced the expression of genes associated with lipid droplet binding proteins, de novo lipogenesis, and TG synthesis in PA-treated HepG2 cells. Dulaglutide also increased the expression of proteins associated with lipolysis and fatty acid oxidation and FAM3A in PA-treated cells. However, exendin-(9-39), a GLP-1R antagonist, reversed the expression of FAM3A, and fatty acid oxidation-associated factors increased due to dulaglutide. In addition, inhibition of FAM3A by siRNA attenuated the reducing effect of dulaglutide on TG content and its increasing effect on regulation of fatty acid oxidation.
Conclusion
These results suggest that dulaglutide could be used therapeutically for improving nonalcoholic fatty liver disease, and its effect could be mediated in part via upregulation of FAM3A expression through a GLP-1R-dependent pathway.
-
Citations
Citations to this article as recorded by  - GLP-1/GLP-1RAs: New Options for the Drug Treatment of NAFLD
Haoran Jiang, Linquan Zang
Current Pharmaceutical Design.2024; 30(2): 100. CrossRef - GLP-1 Receptor Agonists in Non-Alcoholic Fatty Liver Disease: Current Evidence and Future Perspectives
Riccardo Nevola, Raffaella Epifani, Simona Imbriani, Giovanni Tortorella, Concetta Aprea, Raffaele Galiero, Luca Rinaldi, Raffaele Marfella, Ferdinando Carlo Sasso
International Journal of Molecular Sciences.2023; 24(2): 1703. CrossRef - FAM3A mediates the phenotypic switch of human aortic smooth muscle cells stimulated with oxidised low-density lipoprotein by influencing the PI3K-AKT pathway
Lei Yang, Baoshun Du, Shitao Zhang, Maode Wang
In Vitro Cellular & Developmental Biology - Animal.2023; 59(6): 431. CrossRef - ATP Secretion and Metabolism in Regulating Pancreatic Beta Cell Functions and Hepatic Glycolipid Metabolism
Jing Li, Han Yan, Rui Xiang, Weili Yang, Jingjing Ye, Ruili Yin, Jichun Yang, Yujing Chi
Frontiers in Physiology.2022;[Epub] CrossRef - Targeted therapeutics and novel signaling pathways in non-alcohol-associated fatty liver/steatohepatitis (NAFL/NASH)
Xiaohan Xu, Kyle L. Poulsen, Lijuan Wu, Shan Liu, Tatsunori Miyata, Qiaoling Song, Qingda Wei, Chenyang Zhao, Chunhua Lin, Jinbo Yang
Signal Transduction and Targeted Therapy.2022;[Epub] CrossRef
|
KES
