Introduction:
Induction of autophagy could protect against acetaminophen (APAP)-induced hepatotoxicity; however, little is known about the role of autophagy in APAP-induced encephalopathy (APAP-E). This study aimed to evaluate the effects of coenzyme Q10 (CoQ10) and captopril on APAP-E.

Material and methods:
Forty-eight rats were randomly allotted to 4 equal groups: control, an APAP-E, coenzyme Q10-treated (CoQ10-treated), and captopril-treated groups. Behavioral tests were conducted. Serum ammonia and total antioxidant capacity (TAC) and hippocampal Na+/K+ ATPase activity were measured. The expression levels of hippocampal microtubule-associated protein light chain 3 (LC3-II) and beclin-1 mRNA were detected using quantitative polymerase chain reaction (qPCR). General histological, immunohistochemical staining for glial fibrillary acid protein (GFAP) and electron microscopy (EM) of the hippocampus were performed.

Results:
In the APAP-E group, serum ammonia was increased significantly, hippocampal LC3-II and beclin-1 mRNA were elevated insignificantly, while serum TAC and the activity of hippocampal Na+/K+ ATPase were reduced significantly compared with the control group. APAP-E rats showed remarkable degenerative changes in CA1 pyramidal neurons in the form of electron-dense cytoplasm with ill-defined nuclei and accumulation of lysosomal structure-like dense bodies. Increased immunoreactivity of astrocytes for GFAP was observed. Treatment with either CoQ10 or captopril significantly reduced ammonia levels, increased hippocampal LC3-II and beclin-1 mRNA, increased serum TAC and Na+/K+ ATPase activity, and noticeably ameliorated the hippocampal neuronal changes. EM revealed restoration of the normal structure of pyramidal neurons. These effects were more obvious in CoQ10-treated than captopril-treated rats.

Conclusions:
CoQ10 and captopril have neuroprotective effects on APAP-E via enhancing LC3-II, beclin-1 mRNA expression, serum TAC level and hippocampal Na+/K+ ATPase activity.