title: Kefir protective effects against nicotine cessation-induced anxiety and cognition impairments in rats.
abstract: BACKGROUND
  Nicotine as one of the potent psychostimulant drugs is characterized by its parasympathomimetic activity. Upon the abrupt discontinuation of nicotine intake, a number of symptoms such as anxiety, depression and cognition impairment develop. Kefir as a food supplement is rich in tryptophan. In this study, we have evaluated the effects of Kefir on nicotine cessation-induced anxiety, depression and cognition impairment.
  
  
  METHODS
  Forty adult male rats were divided into four groups. All the groups received 6 mg/kg/day of nicotine for 17 days and then the negative control groups got 5 mg/kg/day of normal saline. The positive control groups were given 40 mg/kg/day of Sertraline HCl for 7 days. The group treated with Cow Milk Kefir (CMK) and Soy Milk Kefir (SMK) received 5 mg/kg/day for 7 days. On the 25(th) day, Elevated Plus Maze (EPM), Open Field Test (OFT) and Forced Swim Test (FST) were used to investigate anxiety and depression. In addition, Moris Water Maze was applied to evaluate learning and memory in the animals between the 20(th) and 25(th) days.
  
  
  RESULTS
  The results showed that administration of CMK, SMK and Sertraline had higher anti-depression and anxiolytic effects on nicotine withdrawal-induced depression and anxiety in rats (P < 0.05). Moreover, CMK and SMK improved learning and memory impairment results in the nicotine withdrawal period (P < 0.05).
  
  
  CONCLUSIONS
  This study revealed that Kefir had a potential effect on the treatment of nicotine cessation-induced depression, anxiety and cognition impairment in the animal model. Kefir may be useful for adjunct therapy for nicotine abandonment treatment protocols.
authors.affiliation: Department of Food Hygiene, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran.
authors.forename: Negin
authors.initials: N
authors.lastname: Noori
authors.affiliation: Department of Food Hygiene, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran.
authors.forename: Mohammad Yasan
authors.initials: MY
authors.lastname: Bangash
authors.affiliation: Department of Pharmacology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Majid
authors.initials: M
authors.lastname: Motaghinejad
authors.affiliation: Department of Food Hygiene, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran.
authors.forename: Pantea
authors.initials: P
authors.lastname: Hosseini
authors.affiliation: Department of Food Hygiene, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran.
authors.forename: Behshad
authors.initials: B
authors.lastname: Noudoost
keywords: Anxiety; cognition impairment; kefir; nicotine cessation-induced depression