Effect Of SLC22A1 Genetic Polymorphism On Pharmacokinetic Parameters Of Metformin Hydrochloride In Xinjiang Uygur Healthy Population

Objective: To study the distribution of eight single nucleotide polymorphisms(SNPs)alleles and genotype frequencies of SLC22A1 which is coding gene of organic cation transporter 1(OCT1)in healthy Uygur population of Xinjiang,to further explore the effect of SLC22A1 genetic polymorphism on pharmacokinetic parameters of metformin hydrochloride in Xinjiang Uygur healthy population,and to provide reference for clinical individual drug of metformin.Methods: Two hundred and seventy-six healthy Uygur male volunteers were recruited in Xinjiang.After the extraction of blood genomic DNA,the common genetic polymorphisms of SLC22A1 were genotyped by means of snapshot technique.Based on the above genotyping results,the Uygur healthy subjects carrying the SLC22A1 M420 del gene mutation were screened to recieve the pharmacokinetic test of metformin.A total of 14 subjects were included in this trial.The selected SLC22A1 M420 del gene subjects were divided into three groups according to different genotypes: GG wild homozygote group(n=5),GT mutant heterozygote group(n=5)and TT mutant homozygous group(n=4).In this study,a single-cycle open design was used and all subjects selected were randomly numbered.In the morning,the metformin with the dose of 500 mg was orally administered to each subject.After oral administration,5ml of forearm venous blood in each subject was taken,respectively,at 0,0.5,l,1.5,2,2.5,3,3.5,4,6,8,10,12,24 h.At the same time,the urine were collected at the period of 0-1h,1-3h,3-6h,6-10 h and 10-24 h.The plasma and urine concentration of metformin in each subject was determined by high performance liquid chromatography.The pharmacokinetic parameters were calculated by Kinetic 5.10 software.SPSS17.0 statistical software was used to compare the pharmacokinetic parameters of the subjects in three groups and combined the genotyping results of SLC22A1 M420 del to analyze the association of SLC22A1 M420 del gene polymorphism and pharmacokinetics parameters of metformin.Results: 1.Understanded the distribution of common genetic polymorphisms of SLC22A1 in Xinjiang Uygur healthy population.A total of 8 genetic variants of SLC22A1 SNPs from 276 Uygur healthy male volunteers were measured,and six SNPs variants were detected,which were G465 R,P283L,R61 C,P341L,F160 L,Met420del.While,C859 G and G401 S variations were not detected.The minimum alleles frequencies of G465 R,P283L,R61 C,P341L,F160 L and Met420 del were 0.2%,1.6%,2.7%,4.9%,16.1% and 19.4%,respectively.2.We have successfully established a simple,sensitive method for HPLC-UV detecting the blood and urine concentration of metformin hydrochloride in vivo.3.There were significant differences in the pharmacokinetic parameters in Uygur healthy subjects carrying different genotypes of SLC22A1 M420 del after taking a single dose of 500 mg metformin.The Cmax of the SLC22A1 M420 del GT mutant heterozygote group(1.10±0.09mg/L)and the TT mutant homozygote group(1.17±0.05mg/L)was significantly higher than that of the GG wild type homozygote group(0.89±1.10mg/L);The AUC0-24 of GT mutant heterozygotes group(7.26±1.34mg/h/L)and TT mutant homozygotes group(7.94±1.68mg/h/L)were significantly higher than those of GG wild type Homozygous group(5.49±0.96mg/h/L);The V/F of GT mutant heterozygotes group(541.96±146.13L)and TT mutant homozygotes group(389.94±87.80L)were significantly lower than those of the GG wild type homozygous group(741.41±166.91L).The CL/F of GT mutant heterozygotes(65.47±12.04L/h)and the TT mutant homozygote(59.89±12.45L/h)were significantly lower than those of the GG wild type homozygous group(84.51±14.01L/h);In addition,the fe,u% of GT mutant heterozygotes group(43.44±7.48%)and TT mutant homozygotes group(48.84±12.10%)were significantly higher than those of GG wild-type homozygotes group(30.31±4.65%);The above differences were statistically significant(P<0.05).However,there was no significant difference in Tl/2?AUC0-? and Tmax pharmacokinetic parameters of subjects in the three groups(P>0.05).Conclusion:1.The G465 R,P283L,R61 C,P341L,F160 L and Met420 del mutations of SLC22A1 gene were found in Xinjiang Uygur healthy population,while C859 G and G401 S mutations were not found.The mutations of P283 L,R61C,P341 L,F160L and Met420 del were higher than other mutations in the Xinjiang Uygur healthy population(MAF>1%),while the frequency of G465 R mutation was lower than others(MAF<1%).In addition,there was a significant racial difference for the above genetic polymorphisms of SLC22A1.2.After verification by methodology,the method that HPLC-UV determination of the blood and urine concentration of metformin hydrochloride in human body is suitable for the study of metformin pharmacokinetic.3.The topic that SLC22A1 M420 del gene polymorphism can significantly affect the pharmacokinetics of metformin in the human body,which is firstly confirmed by this study of Xinjiang Uygur healthy population.In conclusion,this study provides an explanation with genetic pharmacology level for the individual differences and provides a theoretical guidance for the rational application of metformin through the molecular level study of healthy subjects.