Liraglutide inhibits receptor for advanced glycation end products (RAGE)/reduced form of nicotinamide-adenine dinucleotide phosphate (NAPDH) signaling to ameliorate non-alcoholic fatty liver disease (NAFLD) in vivo and vitro - PubMed (original) (raw)
Liraglutide inhibits receptor for advanced glycation end products (RAGE)/reduced form of nicotinamide-adenine dinucleotide phosphate (NAPDH) signaling to ameliorate non-alcoholic fatty liver disease (NAFLD) in vivo and vitro
Jingquan Ji et al. Bioengineered. 2022 Mar.
Abstract
The study was designed to investigate the effects of liraglutide and reveal its action mechanism associated with RAGE/NAPDH in NAFLD. The liver tissue was collected for HE, Masson, and ROS staining. Apoptosis levels were detected through TUNEL staining and ROS levels were evaluated through ROS staining. The expression levels of c-Jun N-terminal kinase (JNK) and transforming growth factor-β (TGF-β) were detected through Western blot. JNK and the expression of Collagenα1, Collagenα2 and connective tissue growth factor (CTGF) were detected through RT-qPCR and Western blot and the expression in mouse liver stellate cells (JS-1) cells were evaluated through immunofluorescence staining. We detected the effects of liraglutide on NAFLD in high-fat diet (HFD)-fed mice. Liraglutide treatment improved bridging fibrosis and liver function, as well as lessening ROS levels and the protein levels of RAGE, NOX1, NOX2 and NOX4. In PA and H2O2-induced AML12 cells, liraglutide treatment was able to decrease cell apoptosis, ROS levels and the levels of inflammatory factors including tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6, while it effects were reversed by the induction of RAGE overexpression or NOX2 overexpression. In JS-1 cells treated with medium culturing AML12 cells, liraglutide markedly suppressed cell proliferation and activation, while RAGE overexpression or NOX2 overexpression blunted these effects of liraglutide. Taken together, liraglutide exerts a protective role in improving liver injury caused by HFD, which could be related to decreased apoptosis and oxidative stress of liver cells, as well as decreased proliferation and activation of hepatic stellate cells through RAGE/NOX2.
Keywords: Liraglutide; NOX2; RAGE; nonalcoholic fatty liver disease.
Conflict of interest statement
No potential conflict of interest was reported by the authors.
Figures
Graphical abstract
Figure1
Liraglutide ameliorates liver injury in the HFD mice. (a) The weight, epididymal white fat mass and fasting blood-glucose levels. (b) HE staining of liver tissue. (c) Masson’s trichrome staining. (d) The levels of ALT and AST in the serum of mice. (e) FFA levels. (f, g) Representative images of ROS staining. (h) The levels of RAGE, NOX1, NOX2 and NOX4 in liver tissue of different group. The data were displayed as mean ± SD. n = 7 for each group. ***P < 0.001 compared with Control. # P < 0.05, ## P < 0.01, ### P < 0.001 compared with HFD group.
Figure 2.
Liraglutide reduces the expression levels of RAGE and NOX2 in PA and H2O2-induced AML12 cells. (a) The mRNA levels of RAGE and NOX2. (b) The protein levels of RAGE and NOX2. (c) Cell viability through CCK8 assay. (d) The mRNA levels of RAGE and NOX2. (e) The protein levels of RAGE and NOX2. The data were displayed as mean ± SD. n = 7 for each group. *P < 0.05, **P < 0.01, ***P < 0.001 compared with Control. # P < 0.05, ## P < 0.01, compared with H2O2 200 µM group. ### P < 0.001 compared with PA+ H2O2 group.
Figure 3.
Liraglutide reduces apoptosis levels via RAGE/NOX2 in AML12 cells induced with PA and H2O2. (a, b) RAGE levels. (c, d) NOX2 levels. ***P < 0.001 compared with Ov-NC. (e) TUNEL staining for apoptotic cells. (f) Apoptosis-related protein levels. ***P < 0.001 compared with Control. ### P < 0.001 compared with PA+ H2O2 group. ΔΔ_P_ < 0.001, ΔΔΔ_P_ < 0.001 compared with Ov-NC group.
Figure 4.
Liraglutide reduces ROS production and JNK signals via RAGE/NOX2 in AML12 cells induced with PA and H2O2. (a) ROS staining. (b) JNK and p38-MAPK expression levels. The data are represented as the mean ± SD. ***P < 0.001 compared with Control. ### P < 0.001 compared with PA+ H2O2 group. ΔΔΔ_P_ < 0.001 compared with Ov-NC group.
Figure 5.
Effect of liraglutide treatment in inflammatory factor and TGFβ/SMAD. (a) The mRNA levels of TNF-α, IL-1β and IL-6. (b) The protein levels of TGF and SMAD2. Values are indicated as mean ± SD. ***P < 0.001 compared with Control. ### P < 0.001 compared with PA+ H2O2 group. ΔΔΔ_P_ < 0.001 compared with Ov-NC group.
Figure 6.
Effects of liraglutide in suppressing proliferation and the expression of Collagenα1, Collagenα2, CTGF and α-SMA of JS-1 cells via RAGE/NOX2. (a) CCK8 assay for the detection of cell proliferation. (b) Collagenα1, Collagenα2, CTGF and α-SMA expression through RT-qPCR. (c) Collagenα1, Collagenα2 C and TGF expression through Western blot assay. (d) Immunofluorescence staining for α-SMA. The data were indicated as mean ± SD. ***P < 0.001 compared with Control. ### P < 0.001 compared with PA+ H2O2 group. ΔΔΔ_P_ < 0.001 compared with Ov-NC group.
References
- Zhou Y, Zheng T, Chen H, et al. Microbial intervention as a novel target in treatment of non-alcoholic fatty liver disease progression. Cell Physiol Biochem. 2018;51(5):2123–2135. - PubMed
- Chalasani N, Younossi Z, Lavine JE, et al. The diagnosis and management of nonalcoholic fatty liver disease: practice guidance from the American Association for the Study of Liver Diseases. Hepatology. 2018;67:328–357. - PubMed
- Younossi Z, Anstee QM, Marietti M, et al. Global burden of NAFLD and NASH: trends, predictions, risk factors and prevention. Nat Rev Gastroenterol Hepatol. 2018;15(1):11–20. - PubMed
- Videla LA, Rodrigo R, Araya J, et al. Insulin resistance and oxidative stress interdependency in non-alcoholic fatty liver disease. Trends Mol Med. 2006;12(12):555–558. - PubMed
Publication types
MeSH terms
Substances
LinkOut - more resources
Full Text Sources
Medical
Research Materials
Miscellaneous