Paracetamol or acetaminophen (N-acetyl-para-aminophenol, APAP) is an analgesic and antipy-retic drug commonly used worldwide, implicated in numerous intoxications due to overdose, and causing serious liver damage. APAP can cross the blood-brain barrier and affects brain function in numerous ways including pain signals, temperature regulation, neuroimmune response and emotional behavior; however, its effect on adult neurogenesis has not been thoroughly investi-gated.
We analyze the effect of APAP overdose (750 mg/kg/day), for 3 and 4 consecutive days and after cessation of APAP administration for 6 and 15 days, on cell proliferation and survival in two relevant neurogenic zones: the subgranular zone of the dentate gyrus and the hypothalamus. The involvement of liver damage (plasma transaminases), neuronal activity (c-Fos) and astroglia (GFAP) was also evaluated.
Our results indicated that repeated APAP overdoses were associated with inhibition of adult neurogenesis in a context of elevated liver transaminase levels, neuronal hyperactivity and as-trogliosis. These effects were partially reversed after cessation of APAP administration for 6 and 15 days.
In conclusion, these results suggest that APAP overdose impairs adult neurogenesis in the hip-pocampus and hypothalamus, a fact that may contribute to the effects of APAP on brain function.