N-acetylcysteine relieves neurologic signs of acute ethanol hangover in rats

Abstract

Introduction: Alcohol abuse is one of the grave social and medical problems in many countries, including Russia. Alcohol not only negatively affects health, social and family relationships, but also a person's performance. Hangover, which is a one of the negative consequences of alcohol intake, is a complex of neurological and somatic symptoms that occur when ethanol is almost completely metabolized to acetaldehyde. This condition, despite the severity and potential economic damage, remains poorly understood, and there are no effective medicines to treat it. Aim: to provide an experimental basis for the possibility of using N-acetylcysteine (NAC), a precursor of glutathione, as a medicine for prevention of the neurological and cognitive impairments due to alcohol intoxication. Materials and Methods: The study used male Wistar rats, which were intraperitoneally injected with ethanol at a dose of 3 g/kg to simulate acute ethanol intoxication. Sixty minutes before the injection, the animals from the experimental groups were gavaged with NAC (1 g/kg) or with an equivalent volume of saline. Immediately after awakening and 3 h after it, the animals were assessed for neurological deficits, motor skills, spontaneous motor activity, and cognitive functions. After the completion of the behavioral tests, the animals were euthanized to assess the level of glutathione, triglycerides (TGs), and malonic dialdehyde (MDA) in liver homogenates, and to determine the activity of enzymatic antioxidant systems and serum aminotransferases. Results and Discussion: The ethanol intoxication in the animals from the control group was associated with pronounced signs of neurological and cognitive impairments, including low spontaneous motor and exploratory activity, impaired fine motor skills in the adhesive test, and cognitive function decline in the Morris water maze test. The rats which had received NAC before ethanol injection demonstrated better fine motor skills in the adhesive test, a higher level of spontaneous motor activity and better performance in the Morris water maze test (in comparison to the animals treated with saline before alcohol intoxication). In the animals which had received NAC, the levels of glutathione, MDA, and TGs, as well as the activity of liver antioxidant enzymes, were closer to the values of the intact rats to a greater extent than in the animals that had been injected with ethanol and received saline. Conclusion: Orally administered NAC before acute ethanol intoxication led to a decrease in the severity of neurological deficiency in rats and reduced the amnesic effect of ethanol. This could be due to an improvement of ethanol metabolism and a decrease in the severity of disorders associated with oxidative stress and liver dysfunction.