The influence of inducers on drug-metabolizing enzyme activity and on formation of reactive drug metabolites in the liver

Glutathione S-transferase M1 and T1 genes deletion polymorphisms and blood pressure control among treated essential hypertensive patients in Burkina Faso

OBJECTIVE

Glutathione S-transferases have been associated with experimental resistance to some drugs. The present study investigated the factors associated with blood pressure control in patients with essential hypertension, especially the role of GSTT1 and GSTM1 genes polymorphisms. This cross-sectional study in Burkina Faso consisted of 200 patients with essential hypertension and under treatment.

RESULTS

In the present study, 57.5% (115/200) of patients had their hypertension under control. No statistically significant difference was found between controlled and uncontrolled groups for anthropometric and biochemical parameters as well as for GSTT1 or GSTM1 gene polymorphisms (all p > 0.05). Current alcohol consumption (OR = 3.04; CI 1.88-6.13; p < 0.001), Physical inactivity (OR = 3.07; CI 1.71-5.49; p < 0.001), severe hypertension before any treatment (Grade III [OR = 3.79; CI 2.00-7.17; p < 0.001]) and heart damage (OR = 3, 14; CI 1.59-6.02; p < 0.001) were statistically more frequent in uncontrolled essential hypertensive patients than controlled hypertensive patients.

Genetic polymorphism of drug metabolism enzymes (GSTM1, GSTT1 and GSTP1) in the healthy Malian population

Glutathione S-transferase genes, known to be highly polymorphic, are implicated in the process of phase II metabolism of many substrates, including xenobiotics, anticancer and anti-infective drugs. The detoxification activity is linked to individual genetic makeup. Therefore, the identification of alleles and genotypes in these genes within a population may help to better design genetic susceptibility and pharmacogenetic studies. We performed the present study to establish the frequencies of the GSTM1, GSTT1, and GSTP1 c. 313A > G (rs1695) polymorphisms in 206 individuals of the Malian healthy population. GSTM1 and GSTT1 were genotyped by using multiplex polymerase chain reaction, whereas genotypes of GSTP1 were identified by polymerase chain reaction followed by restriction fragment length polymorphism. The frequencies of GSTM1-null and GSTT1-null genotypes were respectively 24.3 and 41.3%. The observed genotype frequencies for GSTP1 were 25.73% homozygous wild-type AA, 49.03% heterozygous AG and 25.24% homozygous mutant GG. The frequency of GSTP1-A allele was 50.24% versus 49.76% for the GSTP1-G allele. The distribution of these three genes was homogeneous between men and women (p > 0.05). We found no statistical association between the presence of a particular profile of GSTM1 or GSTT1 with the genotypes of GSTP1 (p > 0.05). Nevertheless, we noticed that the majority of the individuals harboring the GSTM1-present or the GSTT1-present harbor also the GSTP1-AG genotype. In addition, the triple genotype GSTM1-present/GSTT1-present/AG was the most frequent with 25.2%. Our findings will facilitate future studies regarding genetic associations of multifactorial diseases and pharmacogenetic, thus opening the way to personalized medicine in our population.