title: Thunbergia laurifolia extract ameliorates cognitive and emotional deficits in olfactorectomized mice.
abstract: BACKGROUND
  Thunbergia laurifolia Lindl. (Acanthaceae) is a Thai medicinal plant used for the detoxification of poison which is likely to be beneficial for the treatment of cognitive deficits including Alzheimer's disease.
  
  
  OBJECTIVE
  To elucidate the effects of Thunbergia laurifolia leaf extract (TLL) on cognitive dysfunction and depression-like behavior in olfactory bulbectomized mice (OBX).
  
  
  METHODS
  OBX mice were treated daily with TLL at the dose of 250 and 500 mg/kg, tacrine, and imipramine, on the day after 10 d of OBX operation. The effects of TLL on cognitive and depression-like behavior of the animals were analyzed. After completing behavioral experiments, the expression levels of cholinergic marker genes encoding ChAT and muscarinic M1 receptor were quantitatively analyzed.
  
  
  RESULTS
  TLL and tacrine reduced OBX-induced cognitive deficits in the object recognition test (ORT) with the time spent for the novel object two times longer than that of the familiar object. Moreover, TLL at the dose of 500 mg/kg and imipramine ameliorated depression-like behavior in the tail suspension test (TST) by reducing the duration of immobility from 25.18% to 3.16% and from 25.18% to 6.48%, respectively. TLL at the dose of 250 and 500 mg/kg reversed the OBX-induced down-regulation of ChAT mRNA expression in the hippocampus from 0.12 to 0.17 and 0.24, respectively, while the down-regulation of mRNA expression of muscarinic M1 receptor was also reversed by TLL from 0.23 to 0.38 and 0.48, respectively.
  
  
  CONCLUSIONS
  TLL ameliorates non-spatial short-term memory deficits in OBX mice, and has the potential to exhibit an antidepressant-like action.
authors.affiliation: Department of Pharmaceutical Chemistry and.
authors.forename: Piyanuch
authors.initials: P
authors.lastname: Rojsanga
authors.forename: Pongtip
authors.initials: P
authors.lastname: Sithisarn
authors.forename: Ken
authors.initials: K
authors.lastname: Tanaka
authors.forename: Daishu
authors.initials: D
authors.lastname: Mizuki
authors.forename: Kinzo
authors.initials: K
authors.lastname: Matsumoto
mesh_terms: D027901:Acanthaceae; D000818:Animals; D003072:Cognition Disorders / Q000188:drug therapy* / Q000523:psychology; D004305:Dose-Response Relationship, Drug; D004644:Emotions / Q000187:drug effects* / Q000502:physiology; D008297:Male; D051379:Mice; D009830:Olfactory Bulb / Q000502:physiology / Q000601:surgery*; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use*; D018515:Plant Leaves
chemical_list: D010936:Plant Extracts
keywords: Alzheimer's disease; Rang Jurd; modified Y-maze test; object recognition test; tail suspension test