Expression of NAT2 in immune system cells and the relation of NAT2 gene polymorphisms in the anti-tuberculosis therapy in Mexican mestizo population

Abstract

Arylamine N-acetyltransferase 2 (NAT2) metabolizes isoniazid (INH) and Single Nucleotide Polymorphisms (SNP) responsible for its activity has been reported. The aim of this study in the Mexican mestizo population was to evaluate NAT2 expression at the protein level in immune cells, as well as the distribution and frequency of six NAT2 SNPs and their association with anti-TB therapy, by measuring the plasma levels of INH and Acetyl-INH (AcINH). We performed genotyping assays of NAT2 SNPs in 40 TB patients and 121 healthy volunteers by real-time PCR. A method for detecting NAT2 in immune cells using flow cytometry was developed. Plasma concentrations of INH and AcINH were obtained by HPLC in TB patients and the Metabolic Ratio (MR) was calculated. The phenotypes obtained in the healthy volunteers were as follows; 18.87 % of subjects had the rapid acetylator phenotype, 45.45 % had the intermediate phenotype and 39.66 % exhibited the slow acetylator phenotype. In the TB patient group, 35 % of patients had the rapid acetylator phenotype, 32.5 % were intermediate and 32.5 % showed the slow acetylator phenotype. A higher expression level of NAT2 in innate immune cells from TB patients compared to those from healthy volunteers was detected (P < 0.013). In TB patients the MR showed a bimodal distribution with an antimode of 0.7, which was used as a threshold value for acetylator classification. A high correspondence between the rapid and slow acetylator phenotype with MR was demonstrated. In conclusion, the 282C>T, 341T>C, 481C>T, 590G>A, 803A>G, 857G>A SNPs of NAT2 gene provides accurate for prediction of the acetylator phenotype in Mexican mestizo population. A statistical difference was found in frequency of rapid metabolizer phenotype, which was higher in TB patients. In addition, the expression of NAT2 protein in immune cells can lead to further studies related to its functional role in the innate immune response against M. tuberculosis and other xenobiotics metabolized by this enzyme.

The role of NAT2 polymorphism and methylation in anti‐tuberculosis drug‐induced liver injury in Mongolian tuberculosis patients

“…It has been reported that 52%‐72% of Caucasians have slow acetylating phenotypes, while 34%‐61% of Africans carry slow acetylated phenotypes . In America, the rate of slow acetylation types ranges from 23% to 75%, while Asians only have 9%‐32% of the slow acetylation phenotype . In this study, we found that slow acetylation in Mongolian tuberculosis patients accounted for 29.4%, which was consistent with Asians.…”

Expression and genotype-dependent catalytic activity of N-acetyltransferase 2 (NAT2) in human peripheral blood mononuclear cells and its modulation by Sirtuin 1

“…The presence of slow acetylation activity SNPs has been linked to the risk of developing type 2 diabetes [7, 8]. The sample of healthy volunteers participating on this study showed a high prevalence of a slow acetylation phenotype consistent with previous reports with larger samples of Mexican [34, 37] and Central American populations [43]. This can be attributed to the admixture effect present on American mestizo groups [44, 45].…”

“…Six SNPs were analyzed: rs1041983 (282C>T), rs1801280 (341T>C), rs1799929 (481C>T), rs1799930 (590G>A), rs1208 (803A>G) and rs1799931 (857G>A). The genotyping assays were performed as previously described [34]. Briefly, A 20X primer and probe mix was supplied for each assay, and a 1X concentration of this mix as well as a half volume of 2X TaqMan® Genotyping Master Mix (Life Technologies, Waltham, MA, USA) and 10 ng/μL of the genomic DNA sample were added to each well.…”

“…NAT2 and SIRT1 expression were evaluated on PBMC using different combinations of monoclonal antibodies on the T, B or NK cell subpopulations as previously reported [24, 33, 34]. Briefly, to detect CD3, CD19 or CD56 molecules on plasmatic membrane an incubation step using the corresponding monoclonal antibodies, anti-CD3-PE, anti-CD19-PE or anti-CD56-PE was performed (BD Biosciences, San Jose, CA, USA).…”

Rol de la farmacogenómica en el régimen de tratamiento de tuberculosis

“…Otros países ya han reportado los genotipos de NAT2 en sus poblaciones, entre ellos están, China (28) , México (28)(29)(30) , Morocco (31) , India (32) y Brasil (33) , encontrado diferencias en sus genotipos comparados con los de otras poblaciones. La Tabla 2a muestra un metaanálisis de las frecuencias de los alelos de NAT2 en nueve poblaciones (31) .…”