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Background Metabolic syndrome (MetS) associated with psychiatric disorders and psychotropic treatments represents a major health issue. 11 beta-Hydroxysteroid dehydrogenase type 1 (11 beta-HSD1) is an enzyme that catalyzes tissue regeneration of active cortisol from cortisone. Elevated enzymatic activity of 11 beta-HSD1 may lead to the development of MetS. Methods We investigated the association between seven HSD11B1 gene (encoding 11 beta-HSD1) polymorphisms and BMI and MetS components in a psychiatric sample treated with potential weight gain-inducing psychotropic drugs (n = 478). The polymorphisms that survived Bonferroni correction were analyzed in two independent psychiatric samples (n(R1) = 168, n(R2) = 188) and in several large population-based samples (n(1) = 5338; n(2) = 123 865; n(3) > 100 000). Results HSD11B1 rs846910-A, rs375319-A, and rs4844488-G allele carriers were found to be associated with lower BMI, waist circumference, and diastolic blood pressure compared with the reference genotype (P-corrected < 0.05). These associations were exclusively detected in women (n = 257) with more than 3.1 kg/m(2), 7.5 cm, and 4.2 mmHg lower BMI, waist circumference, and diastolic blood pressure, respectively, in rs846910-A, rs375319-A, and rs4844488-G allele carriers compared with noncarriers (P-corrected < 0.05). Conversely, carriers of the rs846906-T allele had significantly higher waist circumference and triglycerides and lower high-density lipoprotein-cholesterol exclusively in men (P-corrected = 0.028). The rs846906-T allele was also associated with a higher risk of MetS at 3 months of follow-up (odds ratio: 3.31, 95% confidence interval: 1.53-7.17, P-corrected = 0.014). No association was observed between HSD11B1 polymorphisms and BMI and MetS components in the population-based samples. Conclusions Our results indicate that HSD11B1 polymorphisms may contribute toward the development of MetS in psychiatric patients treated with potential weight gain-inducing psychotropic drugs, but do not play a significant role in the general population. Copyright (C) 2015 Wolters Kluwer Health, Inc. All rights reserved.

Background There is a high interindividual variability in cytochrome P4501A2 (CYP1A2) activity and in its inducibility by smoking, only poorly explained by known CYP1A2 polymorphisms. We aimed to study the contribution of other regulatory pathways, including transcription factors and nuclear receptors, toward this variability. Methods CYP1A2 activity was determined by the paraxanthine/caffeine ratio in 184 smokers and in 113 of them who were abstinent for 4 weeks. Participants were genotyped for 22 polymorphisms in 12 genes. Results A significant influence on CYP1A2 inducibility was observed for the NR1I3 rs2502815 (P=0.0026), rs4073054 (P=0.029), NR2B1 rs3818740 (P=0.0045), rs3132297 (P=0.036), AhR rs2282885 (P=0.040), rs2066853 (P=0.019), NR1I1 rs2228570 (P=0.037), and NR1I2 rs1523130 (P=0.044) polymorphisms. Among these, the NR1I3 rs2502815 (P=0.0045), rs4073054 (P=0.048), and NR2B1 rs3818740 (P=0.031) also influenced CYP1A2 basal activity. Conclusion This is the first in-vivo demonstration of the influence of genes involved in CYP1A2 regulatory pathways on its basal activity and inducibility by smoking. These results need to be confirmed by other studies.

BACKGROUND: (S)-Methadone, metabolized mainly by CYP2B6, shows a wide interindividual variability in its pharmacokinetics and pharmacodynamics. METHODS: Resequencing of the CYP2B6 gene was performed in 12 and 35 selected individuals with high (S)-methadone plasma exposure and low (S)-methadone plasma exposure, respectively, from a previously described cohort of 276 patients undergoing methadone maintenance treatment. Selected genetic polymorphisms were then analyzed in the complete cohort. RESULTS: The rs35303484 (*11; c136A>G; M46V) polymorphism was overrepresented in the high (S)-methadone level group, whereas the rs3745274 (*9; c516G>T; Q172H), rs2279344 (c822+183G>A), and rs8192719 (c1294+53C>T) polymorphisms were underrepresented in the low (S)-methadone level group, suggesting an association with decreased CYP2B6 activity. Conversely, the rs3211371 (*5; c1459C>T; R487C) polymorphism was overrepresented in the low-level group, indicating an increased CYP2B6 activity. A higher allele frequency was found in the high-level group compared with the low-level group for rs3745274 (*9; c516G>T; Q172H), rs2279343 (*4; c785A>G; K262R) (together representing CYP2B6*6), rs8192719 (c1294+53C>T), and rs2279344 (c822+183G>A), suggesting their involvement in decreased CYP2B6 activity. These results should be replicated in larger independent cohorts. CONCLUSION: Known genetic polymorphisms in CYP2B6 contribute toward explaining extreme (S)-methadone plasma levels observed in a cohort of patients following methadone maintenance treatment.

The expression on lymphocytes of P-glycoprotein, an efflux transporter encoded by the ABCB1 gene, might influence cyclosporine intracellular concentration.ABCB1 genotypes, cyclosporine intracellular and blood concentrations were determined in 64 stable renal, liver or lung transplant recipients.Cyclosporine intracellular concentration correlated moderately with blood concentration (r=0.30, P0.00005). The ABCB1 1199A carriers presented a 1.8-fold decreased cyclosporine intracellular concentration (P=0.04), whereas the 3435T carriers presented a 1.7-fold increase (P=0.02) as well as a 1.2-fold increased blood concentration (P=0.04). In contrast, ABCB1 61AG, 1236CT and 2677GT polymorphisms did not influence cyclosporine intracellular and blood concentrations.This is the first report demonstrating that ABCB1 polymorphisms influence cyclosporine intracellular concentration. Interestingly, its influence on intracellular concentration is significantly higher than on blood concentration (P0.002). This may therefore modulate cyclosporine immunosuppressive activity.

CYP3A4, CYP3A5 and CYP3A7 are hepatic enzymes that metabolize about 50% of drugs on the market, with a large overlap in their specificities. We investigated the genetic bases that contribute to the variation of CYP3A activity.We phenotyped 251 individuals from two independent studies (182 patients treated with methadone and 69 patients with clozapine) for CYP3A activity using the midazolam phenotyping test and genotyped them for CYP3A4, CYP3A5, and CYP3A7 genetic variants, including the single nucleotide polymorphism (SNP) rs4646437CT in intron 7 of CYP3A4. Owing to the fact that CYP enzymes require electron transfer through the P450 oxidoreductase (POR), and functional impairment has been shown for the POR*28 SNP, this polymorphism was also analysed.We show that CYP3A4, CYP3A5 and CYP3A7 genotypes, including the SNP rs4646437CT, do not reflect the inter-individual variability of CYP3A activity (P0.1). In contrast, POR*28 TT genotype presents a 1.6-fold increase in CYP3A activity compared with POR*28C carriers (n = 182, P = 0.004). This finding was replicated in the second independent dataset (n = 69, P = 0.04).The SNP POR*28 seems to be a better genetic marker of the variability of total CYP3A activity in vivo than CYP3A4, CYP3A5 and CYP3A7 genetic variants.