Visualization and Quantification of Lipogenesis Using a -GLuc Mouse Model

Overview

Journal Ann Transl Med

Publisher AME Publishing Company

Date 2022 Oct 21

PMID 36267736

Authors

Wenjiao Li

Song Zhang

Xin Fu

Jiehao Zhang

Renlong Li

Haohao Zhang

Qingling An

Weizhen Wang

Zuhong Tian

Changhong Shi

Yongzhan Nie

Affiliations

Soon will be listed here.

Abstract

Background: De novo lipogenesis (DNL) is a dynamic process that converts excess carbohydrates into fatty acids to maintain cellular homeostasis. Dysregulation of DNL is associated with diverse obesity-related diseases and many tumor types. Therefore, monitoring DNL in real-time with high sensitivity should be highly beneficial when screening therapeutic agents for their potential use as obesity treatments.

Methods: A sequence coding for Gaussia luciferase (GLuc) preceded by a 2A peptide was inserted into the murine fatty acid synthase (FASN) genetic locus by homologous recombination to generate FASN-2A-GLuc mice. The luciferase mouse model was evaluated in conditions of physical and pharmacological stimuli by in vivo and ex vivo imaging.

Results: The distribution of bioluminescence signals in different organs was identical to the FASN expression: high in white fat, brown fat, and the lungs. In addition, the bioluminescence signals accurately recapitulated the dynamic change of FASN in response to fasting and refeeding conditions. Moreover, with this murine reporter model, we also discovered that fatostatin, a synthetic inhibitor of sterol regulatory element-binding proteins, effectively inhibited DNL in multiple organs, especially in adipose tissues under a high-carbohydrate diet.

Conclusions: Our FASN-2A-GLuc reporter mouse model proved to be a sensitive visualization tool for monitoring both systemic and organ-specific DNL in real time.

References

Talebi A, Dehairs J, Rambow F, Rogiers A, Nittner D, Derua R . Sustained SREBP-1-dependent lipogenesis as a key mediator of resistance to BRAF-targeted therapy. Nat Commun. 2018; 9(1):2500. PMC: 6021375. DOI: 10.1038/s41467-018-04664-0. View

Liu Y, Dentin R, Chen D, Hedrick S, Ravnskjaer K, Schenk S . A fasting inducible switch modulates gluconeogenesis via activator/coactivator exchange. Nature. 2008; 456(7219):269-73. PMC: 2597669. DOI: 10.1038/nature07349. View

Shaikh F, Kurtys E, Kubassova O, Roettger D . Reporter gene imaging and its role in imaging-based drug development. Drug Discov Today. 2020; 25(3):582-592. DOI: 10.1016/j.drudis.2019.12.010. View

Brejchova K, Balas L, Paluchova V, Brezinova M, Durand T, Kuda O . Understanding FAHFAs: From structure to metabolic regulation. Prog Lipid Res. 2020; 79:101053. DOI: 10.1016/j.plipres.2020.101053. View

Koutsoudakis G, Romero-Brey I, Berger C, Perez-Vilaro G, Monteiro Perin P, Vondran F . Soraphen A: A broad-spectrum antiviral natural product with potent anti-hepatitis C virus activity. J Hepatol. 2015; 63(4):813-21. DOI: 10.1016/j.jhep.2015.06.002. View

Wang H, Willershauser M, Karlas A, Gorpas D, Reber J, Ntziachristos V . A dual Ucp1 reporter mouse model for imaging and quantitation of brown and brite fat recruitment. Mol Metab. 2018; 20:14-27. PMC: 6358570. DOI: 10.1016/j.molmet.2018.11.009. View

Cohen C, Li K, Alazraki A, Beysen C, Carrier C, Cleeton R . Dietary sugar restriction reduces hepatic de novo lipogenesis in adolescent boys with fatty liver disease. J Clin Invest. 2021; 131(24). PMC: 8670836. DOI: 10.1172/JCI150996. View

Barrios-Correa A, Estrada J, Contreras I . Leptin Signaling in the Control of Metabolism and Appetite: Lessons from Animal Models. J Mol Neurosci. 2018; 66(3):390-402. DOI: 10.1007/s12031-018-1185-0. View

Heidenreich S, Weber P, Stephanowitz H, Petricek K, Schutte T, Oster M . The glucose-sensing transcription factor ChREBP is targeted by proline hydroxylation. J Biol Chem. 2020; 295(50):17158-17168. PMC: 7863887. DOI: 10.1074/jbc.RA120.014402. View

10.

Imamura F, Fretts A, Marklund M, Ardisson Korat A, Yang W, Lankinen M . Fatty acids in the de novo lipogenesis pathway and incidence of type 2 diabetes: A pooled analysis of prospective cohort studies. PLoS Med. 2020; 17(6):e1003102. PMC: 7292352. DOI: 10.1371/journal.pmed.1003102. View

11.

Batchuluun B, Pinkosky S, Steinberg G . Lipogenesis inhibitors: therapeutic opportunities and challenges. Nat Rev Drug Discov. 2022; 21(4):283-305. PMC: 8758994. DOI: 10.1038/s41573-021-00367-2. View

12.

Sekiya M, Yahagi N, Matsuzaka T, Takeuchi Y, Nakagawa Y, Takahashi H . SREBP-1-independent regulation of lipogenic gene expression in adipocytes. J Lipid Res. 2007; 48(7):1581-91. DOI: 10.1194/jlr.M700033-JLR200. View

13.

Liu Y, Zhang N, Zhang H, Wang L, Duan Y, Wang X . Fatostatin in Combination with Tamoxifen Induces Synergistic Inhibition in ER-Positive Breast Cancer. Drug Des Devel Ther. 2020; 14:3535-3545. PMC: 7457819. DOI: 10.2147/DDDT.S253876. View

14.

Tannous B, Teng J . Secreted blood reporters: insights and applications. Biotechnol Adv. 2011; 29(6):997-1003. PMC: 3189544. DOI: 10.1016/j.biotechadv.2011.08.021. View

15.

Nogalska A, Sucajtys-Szulc E, Swierczynski J . Leptin decreases lipogenic enzyme gene expression through modification of SREBP-1c gene expression in white adipose tissue of aging rats. Metabolism. 2005; 54(8):1041-7. DOI: 10.1016/j.metabol.2005.03.007. View

16.

Tannous B . Gaussia luciferase reporter assay for monitoring biological processes in culture and in vivo. Nat Protoc. 2009; 4(4):582-91. PMC: 2692611. DOI: 10.1038/nprot.2009.28. View

17.

Smith G, Shankaran M, Yoshino M, Schweitzer G, Chondronikola M, Beals J . Insulin resistance drives hepatic de novo lipogenesis in nonalcoholic fatty liver disease. J Clin Invest. 2019; 130(3):1453-1460. PMC: 7269561. DOI: 10.1172/JCI134165. View

18.

Shimano H, Shimomura I, Hammer R, Herz J, Goldstein J, Brown M . Elevated levels of SREBP-2 and cholesterol synthesis in livers of mice homozygous for a targeted disruption of the SREBP-1 gene. J Clin Invest. 1997; 100(8):2115-24. PMC: 508404. DOI: 10.1172/JCI119746. View

19.

Flannery C, Dufour S, Rabol R, Shulman G, Petersen K . Skeletal muscle insulin resistance promotes increased hepatic de novo lipogenesis, hyperlipidemia, and hepatic steatosis in the elderly. Diabetes. 2012; 61(11):2711-7. PMC: 3478531. DOI: 10.2337/db12-0206. View

20.

AlSawaftah N, Farooq A, Dhou S, Majdalawieh A . Bioluminescence Imaging Applications in Cancer: A Comprehensive Review. IEEE Rev Biomed Eng. 2020; 14:307-326. DOI: 10.1109/RBME.2020.2995124. View