Melatonin modulates the autophagic response in acute liver failure induced by the rabbit hemorrhagic disease virus.
Autophagy is an important survival pathway and participates in the host response to infection. Beneficial effects of melatonin have been previously reported in an animal model of acute liver failure (ALF) induced by the rabbit hemorrhagic disease virus (RHDV). This study was aimed to investigate whether melatonin protection against liver injury induced by the RHDV associates to modulation of autophagy. Rabbits were infected with 2 × 10(4) hemagglutination units of a RHDV isolate and received 20 mg/kg melatonin at 0, 12, and 24 hr postinfection. RHDV induced autophagy, with increased expression of beclin-1, ubiquitin-like autophagy-related (Atg)5, Atg12, Atg16L1 and sequestrosome 1 (p62/SQSTM1), protein 1 light chain 3 (LC3) staining, and conversion of LC3-I to autophagosome-associated LC3-II. These effects reached a maximum at 24 hr postinfection, in parallel to extensive colocalization of LC3 and lysosome-associated membrane protein (LAMP)-1. The autophagic response induced by RHDV infection was significantly inhibited by melatonin administration. Melatonin treatment also resulted in decreased immunoreactivity for RHDV viral VP60 antigen and a significantly reduction in RHDV VP60 mRNA levels, oxidized to reduced glutathione ratio (GSSG/GSH), caspase-3 activity, and immunoglobulin-heavy-chain-binding protein (BiP) and CCAAT/enhancer-binding protein homologous protein (CHOP) expression. Results indicate that, in addition to its antioxidant and antiapoptotic effects, and the suppression of ER stress, melatonin induces a decrease in autophagy associated with RHDV infection and inhibits RHDV RNA replication. Results obtained reveal novel molecular pathways accounting for the protective effect of melatonin in this animal model of ALF.
Institute of Biomedicine (IBIOMED), University of León, León, Spain.
Beatriz
B
San-Miguel
Irene
I
Crespo
Daniela
D
Vallejo
Marcelino
M
Álvarez
Jesús
J
Prieto
Javier
J
González-Gallego
María J
MJ
Tuñón
D000818:Animals; D001343:Autophagy / Q000187:drug effects*; D017250:Caliciviridae Infections / Q000503:physiopathology / Q000517:prevention & control*; D004195:Disease Models, Animal; D017929:Hemorrhagic Disease Virus, Rabbit / Q000378:metabolism / Q000472:pathogenicity*; D017114:Liver Failure, Acute / Q000503:physiopathology*; D008297:Male; D008550:Melatonin / Q000627:therapeutic use*; D011817:Rabbits; D015678:Viral Structural Proteins / Q000096:biosynthesis
D015678:Viral Structural Proteins; C081149:viral protein 60, rabbit hemorrhagic disease virus; D008550:Melatonin
acute liver failure; autophagy; melatonin; rabbit hemorrhagic disease