Protective effects of luteolin against acetaminophen-induced acute liver failure in mouse.

Acetaminophen (APAP) is widely used as a safety analgesic and antipyretic agent. Although considered safe at therapeutic doses, overdose of APAP can cause acute liver injury that is sometimes fatal, requiring efficient pharmacological intervention. Luteolin is a naturally occurring flavonoid which is abundant in plants. The objective of this study was to investigate corresponding anti-oxidative and anti-inflammatory activities of luteolin, using acetaminophen-treated mice as a model system. Male C57BL/C mice were randomly divided into three groups (n=6 each). The control group was given phosphate buffered saline (PBS) orally. The APAP group was given APAP by intraperitoneal injection (i.p) at 300 mg/kg suspended in PBS. The luteolin-treated group was given APAP and luteolin (0-100 mg/kg/day, 1 or 3 days before APAP administration) suspended in PBS orally. 16 h after APAP administration, the liver and serum were collected to determine the liver injury. Luteolin administration significantly decreased acetaminophen-induced serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), malondialdehyde (MDA) levels, as well as glutathione (GSH) depletion and decrease of superoxide dismutase (SOD). Luteolin restored SOD, GSH and GSH-px activities and depressed the expression of pro-inflammatory factors, such as inducible nitric oxide synthase (i-NOS), TNF-α, nuclear factor kappa B (NF-κB), and IL-6, respectively. Moreover, luteolin down-regulated acetaminophen-induced nitrotyrosine (NT) formation and endoplasmic reticulum (ER) stress. These results suggest the presence of anti-oxidative, anti-inflammatory and anti-ER stress properties of luteolin in response to acetaminophen-induced liver injury in mice.

Tai M ，Zhang J ，Song S ，Miao R ，Liu S ，Pang Q ，Wu Q ，Liu C ... -  《-》

Saponins (Ginsenosides) from the Leaves of Panax quinquefolius Ameliorated Acetaminophen-Induced Hepatotoxicity in Mice.

Xu XY ，Hu JN ，Liu Z ，Zhang R ，He YF ，Hou W ，Wang ZQ ，Yang G ，Li W ... -  《-》

Astaxanthin pretreatment attenuates acetaminophen-induced liver injury in mice.

Acetaminophen (APAP) is a conventional drug widely used in the clinic because of its antipyretic-analgesic effects. However, accidental or intentional APAP overdoses induce liver injury and even acute liver failure (ALF). Astaxanthin (ASX) is the strongest antioxidant in nature that shows preventive and therapeutic properties, such as ocular protection, anti-tumor, anti-diabetes, anti-inflammatory, and immunomodulatory effects. The aim of present study was to determine whether ASX pretreatment provides protection against APAP-induced liver failure. Male C57BL/6 mice were randomly divided into 7 groups, including control, oil, ASX (30mg/kg or 60mg/kg), APAP and APAP+ASX (30mg/kg or 60mg/kg) groups. Saline, olive oil and ASX were administered for 14days. The APAP and APAP+ASX groups were given a peritoneal injection of 700mg/kg or 300mg/kg APAP to determine the 5-day survival rate and for further observation, respectively. Blood and liver samples were collected to detect alanine transaminase (ALT), aspartate transaminase (AST), inflammation, oxidative stress and antioxidant systems, and to observe histopathologic changes and key proteins in the mitogen-activated protein kinase (MAPK) family. ASX pretreatment before APAP increased the 5-day survival rate in a dose-dependent manner and reduced the ALT, AST, hepatic necrosis, reactive oxygen species (ROS) generation, lipid peroxidation (LPO), oxidative stress and pro-inflammatory factors. ASX protected against APAP toxicity by inhibiting the depletion of glutathione (GSH) and superoxide dismutase (SOD). Administration of ASX did not change the expression of c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and P38. However, phosphorylation of JNK, ERK and P38 was reduced, consistent with the level of tumor necrosis factor alpha (TNF-α) and TNF receptor-associated factor 2 (TRAF2). ASX provided protection for the liver against APAP hepatotoxicity by alleviating hepatocyte necrosis, blocking ROS generation, inhibiting oxidative stress, and reducing apoptosis by inhibiting the TNF-α-mediated JNK signal pathway and by phosphorylation of ERK and P38, which made sense in preventing and treating liver damage.

Zhang J ，Zhang S ，Bi J ，Gu J ，Deng Y ，Liu C ... -  《-》

Inhibition of acetaminophen-induced hepatotoxicity in mice by exogenous thymosinβ4 treatment.

To study the effects of exogenous thymosinβ4 (Tβ4) treatment in acetaminophen (APAP)-induced hepatotoxicity. Liver injury was induced in mice by a single intraperitoneal injection of APAP (500 mg/kg). Exogenous Tβ4 was intraperitoneally administrated at 0 h, 2 h and 4 h after APAP injection. Chloroquine (CQ) (60 mg/kg) was intraperitoneally injected 2 h before APAP administration to inhibit autophagy. Six hours after APAP injection liver injury was evaluated by histological examinations, biochemical measurements and enzyme linked immunosorbent assay (ELISAs). Western blots were performed to detect proteins expression. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were significantly increased 6 h after APAP administration, but were significantly reduced by co-administration of Tβ4. Histological examinations demonstrated that Tβ4 reduced necrosis and inflammation induced by APAP. Immunofluorescence showed that Tβ4 suppressed APAP-induced translocation of high mobility group box-1 protein (HMGB1) from the nucleus to cytosol and intercellular space. Hepatic glutathione (GSH) depletion, malondialdehyde (MDA) formation and decreased superoxide dismutase (SOD) activities induced by APAP were all attenuated by Tβ4. APAP-induced increases in hepatic nuclear factor-κB (NF-κB) p65 protein expression and inflammatory cytokines production including interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) were reduced by Tβ4 treatment. Increased LC3 and p62 proteins in the liver tissues of APAP-treated mice were decreased by Tβ4 treatment, which indicated the enhancement of autophagy flux by Tβ4. Furthermore, inhibiting autophagy by CQ abrogated the protective effects of Tβ4 against APAP hepatotoxicity. Exogenous Tβ4 treatment exerts protective effects against APAP-induced hepatotoxicity in mice. The underneath molecular mechanisms may involve autophagy enhancement and inhibition of oxidative stress by Tβ4.

Wang L ，Li X ，Chen C 《-》

Protective Effects of Tormentic Acid, a Major Component of Suspension Cultures of Eriobotrya japonica Cells, on Acetaminophen-Induced Hepatotoxicity in Mice.

Jiang WP ，Huang SS ，Matsuda Y ，Saito H ，Uramaru N ，Ho HY ，Wu JB ，Huang GJ ... -  《MOLECULES》