Majallah-i Dānishgāh-i ̒Ulūm-i Pizishkī-i Bābul (Nov 2012)
Determination of CYP1A2 Phenotype after Oral Administration of Caffeine in a Sample of Healthy Volunteer from Mazandaran Province
Abstract
BACKGROUND AND OBJECTIVE: Assay of caffeine (CA) plasma concentration can help to find out the activity level of hepatic microsomal cytochrome oxidase 1A2 (CYP1A2). This study was conducted to evaluate the phenotype of activity of CYP2A1 in a sample of Iranian volunteers based on salivary concentration of CA as typical probe of CYP1A2.METHODS: Saliva concentration of CA in 100 Iranian healthy subjects from Mazandaran province (82 men and 18 women) was measured at 0, 0.5, 2, and 5 h after drinking a cup of coffee containing 50 mg caffeine using HPLC method. C8 analytical column and a mobile phase composed of methanol (60%) and water (40%) were used for the chromatographic separation. The peak was detected using a UV detector set at 210 nm.FINDINGS: The mean ± SD of age and body mass index were 24.5 ± 6.9 years (range: 18-55 years) and 23.45± 3.7 (range: 16.7-37.4), respectively. The CV was 3.2% and good linearity (R2= 0.997) was confirmed. The mean elimination half time of CA was 2.01 ± 0.124 h (1.98 h for females and 2.02 h for males) and elimination half-time of CA in above 30 years old (2.05 h) was higher than below 30 years old (2.00 h). The mean Cmax of CA was 0.16 ± 0.02 micg/ml and Kel was calculated 0.41 ± 0.016.CONCLUSION: A normal phenotype of CYP2A1 activity was observed in the Iranian participants in this study. The CYP2A1 activity is higher in elderly subjects than in young.
