Thus, RA might be able to change
the balance of AP-1 and NFAT activity during T-cell activation, resulting in expression changes find more of specific genes. In summary, RA ameliorated Con A- but not α-GalCer-induced liver injury. This protective effect of RA specific to Con A-induced hepatitis may be due to the different molecular mechanism of the liver injuries. According to our results, RA has therapeutic potential in protecting against liver damage by various agents, especially in the case of fulminant hepatitis. However, before administering therapy with RA, the pathogenic mechanism of specific hepatitis needs to be considered. Six- to 8-week-old female C57BL/6 mice were purchased from Orient Bio. All mice were bred and maintained selleck compound in specific pathogen-free conditions. All studies conformed to the principles for laboratory animal research outlined by Seoul National University (Seoul, Korea). α-GalCer, kindly provided by Dr. Sanghee Kim (Seoul National University, Seoul, Korea), was dissolved in 0.5% Tween 20 in saline [40]. ATRA (Sigma-Aldrich, St. Louis, MO, USA) was dissolved in DMSO, further diluted in olive oil for injection, and 35 mg/kg of RA was intraperitoneally (i.p.) injected into the mice 16 h before injecting Con A or α-GalCer. Disulfiram was dissolved
in DMSO, further diluted in olive oil, and injected i.p. at a concentration of 10 mg/kg. The antagonist of RAR-α (Ro 41–5253) was purchased from Enzo Life Science (NY, USA), and the antagonists against RAR-γ (MM11253) and OSBPL9 RXR (UVI3003) were purchased from Tocris Bioscience (Bristol, UK). They were dissolved in DMSO. Intracellular staining was performed with BD Cytofix/Cytoperm Plus (BD Biosciences, San Jose, CA, USA) according to the manufacturer’s instructions without additional stimulation ex vivo. The antibodies were purchased from BioLegend (San Diego, CA, USA). The stained cells were analyzed with a FACSCalibur flow cytometer (BD
Biosciences) and CellQuest Pro software (BD Biosciences). Con A (Sigma-Aldrich) was dissolved in PBS and intravenously (i.v.) injected into the mice at a concentration of 20 mg/kg. For the survival study, the Con A dosage was increased to 30 mg/kg. The mice were euthanized after becoming moribund. For the disulfiram treatment study, the Con A dosage used for alanine aminotransferase (ALT) detection was 15 mg/kg and for survival monitoring was 17 mg/kg. The level of ALT was measured using Fuji-Dri Chem (Fuji Film, Tokyo, Japan) in accordance with the manufacturer’s instructions. Five micrograms of α-GalCer was further diluted in PBS and i.v. injected into the mice. For histology analysis, livers were fixed in 10% formalin and embedded in paraffin. Sections were stained with H&E at Reference Biolabs (Seoul, South Korea). Anti-asialoGM1 (200 μg) was administered i.p. to mice, followed by ATRA treatment (35 mg/kg) 16 h before Con A i.v. injection.