OBJECTIVE To investigate the hepato-protective mechanism of thymoquinone (TQ) onthe development of
acetaminophen (
APAP )- induced
liver injury .
METHODS In vivo,
male kunming
mice were injected with a
single dose of 300 mg·kg-1
APAP . Some
mice were pretreated with TQ (5 or 20 mg·kg-1) and
N-acetylcysteine (NAC, 300 mg·kg-1) 2 h before
APAP injection .
Mice were euthanized at 2 h, 6 h, 12 h after
APAP treatment .
In vitro ,
human Chang
liver cells were incubated with 3.125, 6.25 or 12.5 μmol·L-1 TQ, 10 μmol·L-1 SP600125 and 500 μmol·L-1 AICAR in the presence of
APAP for 24 h.
Cell viability were analyzed by MTT assay,
protein expressions were assessed by
Western blot . RESULTS TQ pretreatment significantly reduced
serum aminotransferase and increased hepatic gluta?
thione (GSH) and
glutathione peroxidase (GSH-PX) activities, while significantly inhibited
interleukin-1 β(
IL-1 β) levels. TQ significantly inhibited
c-Jun N-terminal kinase (JNK),
extracellular signal regulated kinase (ERK) and P38
phosphorylation induced by
APAP . Moreover, TQ inhibited
phosphatidylinositol 3-
kinase (PI3K)/
mammalian target of rapamycin (mTOR) signaling activation and activated AMPK
phosphorylation induced by
APAP . In addition, TQ inhibited
signal transducer and activator of transcription 3 (STAT3)
phosphorylation on
APAP -induced
liver injury .
In vitro ,
APAP enhanced JNK
phosphorylation and attenuated AMPK
phosphorylation in Chang
liver cells , and these effects were blocked by pretreatment with TQ, SP600125 (JNK inhibitor) and AICAR (AMPK activator). CONCLUSION Our findings suggest that TQ may actively prevent
APAP -induced
liver injury , and this effect may be mediated by JNK and AMPK signaling pathways.