title: Role of decreased plasma tryptophan in memory deficits observed in type-I diabetes.
abstract: OBJECTIVE
  To investigate the relationship between plasma tryptophan and the occurrence of memory dysfunctions in male and female type 1 diabetics.
  
  
  METHODS
  The case-control study was conducted at two urban healthcare facilities in Karachi from January to June 2009, and comprised 100 diabetic subjects of among whom were 50 men and 50 women. The controls were also similar in number and gender. A questionnaire was used to evaluate the memory impairment in the subjects. Plasma tryptophan was determined by high performance liquid chromatography with ultra-violet method. Students' t test was used to analyse tryptophan data.
  
  
  RESULTS
  There was considerable memory impairment in the cases (n = 40) compared to the controls (n = 5). Results also showed a significant (p < 0.01) decrease in plasma tryptophan levels in both male and female diabetic patients.
  
  
  CONCLUSIONS
  Diabetic subjects exhibited occurrence of memory impairment with concomitant decline in plasma tryptophan levels. The findings indicate that decreased brain uptake of tryptophan and lowered brain 5-hydroxytryptamine levels may be responsible for the memory deficits seen in diabetics.
authors.affiliation: Neurochemistry and Biochemical Neuropharmacology Research Unit, Department of Biochemistry, University of Karachi, Pakistan. saara_ahmad@hotmail.com
authors.forename: Saara
authors.initials: S
authors.lastname: Ahmad
authors.forename: Saiqa
authors.initials: S
authors.lastname: Tabassum
authors.forename: Saida
authors.initials: S
authors.lastname: Haider
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000097:blood* / Q000209:etiology*; D008875:Middle Aged; D014364:Tryptophan / Q000097:blood*
chemical_list: D014364:Tryptophan