Intuitive pharmacogenetic dosing of risperidone according to CYP2D6 phenotype extrapolated from genotype in a cohort of first episode psychosis patients.

Eur Neuropsychopharmacol. 2017 Apr 04;:

Authors: Mas S, Gassó P, Torra M, Bioque M, Lobo A, González-Pinto A, Olmeda MS, Corripio I, Vieta E, Castro-Fornieles J, Rodriguez-Jimenez R, Bobes J, Usall J, Llerena A, Saiz-Ruiz J, Bernardo M, Lafuente A, PEPs Group

Abstract
Risperidone (R) is the most prescribed antipsychotic drug for patients with a first episode of psychosis (FEP). In a naturalistic cohort of chronic psychiatric inpatients, we demonstrated that clinicians adjust R dosage by CYP2D6 activity, despite being blinded to the genotype, which we described as an "intuitive pharmacogenetic" process. The aim of the present study is to replicate our previous findings of intuitive pharmacogenetic in a cohort of FEP patients using CYP2D6 phenotype extrapolated from genotypes. 70 FEP patients, under baseline treatment with R monotherapy were genotyped using the iPLEX® ADME PGx multiplex panel and TaqMan® Genotyping and Copy Number Assays. Plasma concentrations of R and its metabolite, 9-hydroxyrisperidone (9-OH), were determined. The predictive properties of those variables associated with R dosage were tested using a multiple linear regression model as well as regression trees. Significant differences in the mean daily dosage of R among CYP2D6 phenotypes were observed (Kruskal-Wallis test p=0.02): PM (4.00±2.3mg/mL), IM (4.56±2.44), EM (6.22±4.0mg/day) and UM (10.20±4.91mg/day). However, non-significant differences were observed in the R/9-OH ratio or in the Concentration/Dose ratio. Regression tree provided better estimations of R dosage than the multiple linear regression model (MAE=0.958 and R(2)=0.871). We confirm the "intuitive pharmacogenetic" dosing of R according to the CYP2D6 phenotype in a FEP cohort. The results presented provides a rationale for the clinical use of CYP2D6 genotyping in personalized medicine.

PMID: 28389049 [PubMed - as supplied by publisher]

Regulation of drug metabolism and toxicity by multiple factors of genetics, epigenetics, lncRNAs, gut microbiota, and diseases: a meeting report of the 21(st) International Symposium on Microsomes and Drug Oxidations (MDO).

Acta Pharm Sin B. 2017 Mar;7(2):241-248

Authors: Yu AM, Ingelman-Sundberg M, Cherrington NJ, Aleksunes LM, Zanger UM, Xie W, Jeong H, Morgan EM, Turnbaugh PJ, Klaassen CD, Bhatt AP, Redinbo MR, Hao P, Waxman DJ, Wang L, Zhong XB

Abstract
Variations in drug metabolism may alter drug efficacy and cause toxicity; better understanding of the mechanisms and risks shall help to practice precision medicine. At the 21(st) International Symposium on Microsomes and Drug Oxidations held in Davis, California, USA, in October 2-6, 2016, a number of speakers reported some new findings and ongoing studies on the regulation mechanisms behind variable drug metabolism and toxicity, and discussed potential implications to personalized medications. A considerably insightful overview was provided on genetic and epigenetic regulation of gene expression involved in drug absorption, distribution, metabolism, and excretion (ADME) and drug response. Altered drug metabolism and disposition as well as molecular mechanisms among diseased and special populations were presented. In addition, the roles of gut microbiota in drug metabolism and toxicology as well as long non-coding RNAs in liver functions and diseases were discussed. These findings may offer new insights into improved understanding of ADME regulatory mechanisms and advance drug metabolism research.

PMID: 28388695 [PubMed]

Genome-Wide Association and Replication Study of Hepatotoxicity Induced by Antiretrovirals Alone or with Concomitant Anti-Tuberculosis Drugs.

OMICS. 2017 Apr;21(4):207-216

Authors: Petros Z, Lee MT, Takahashi A, Zhang Y, Yimer G, Habtewold A, Schuppe-Koistinen I, Mushiroda T, Makonnen E, Kubo M, Aklillu E

Abstract
Drug-induced hepatotoxicity (DIH) is a common adverse event that is associated with both antiretroviral (ARV) and anti-tuberculosis drugs (ATD). Moreover, the genetic variations predisposing ARV- and ARV-ATD-induced liver toxicity in African populations are not well investigated, despite the two diseases being the major global health problems in sub-Saharan Africa. We performed a genome-wide association study (GWAS) and replication study to identify the genetic variants linked to the risk of developing DIH due to ARV drugs alone, and ARV-ATD co-treatment in Ethiopian HIV-positive patients. Treatment-naïve newly diagnosed HIV patients (n = 719) with or without tuberculosis (TB) co-infection were enrolled prospectively and received efavirenz-based ARV therapy with or without rifampicin-based short course ATD, respectively. Whole-genome genotyping was performed by using the Illumina Omni Express Exome Bead Chip genotyping array with 951,117 single nucleotide polymorphisms (SNPs) on a total of 41 cases of DIH, and 452 people without DIH (treatment tolerants). The replication study was carried out for 100 SNPs with the lowest p-values (top SNPs) by using an independent cohort consisting of 18 DIH cases and 208 treatment tolerants. We identified a missense SNP rs199650082 (2756G→A, R919Q, p = 1.4 × 10(-6), odds ratio [OR] = 18.2, 95% confidence interval [CI] = 7.1-46.9) in an endoplasmic reticulum to the nucleus signaling-1 (ERN1) gene on chromosome 17 to be associated with DIH in the ARV-only cohort. In the ARV-ATD co-treatment groups, rs4842407, a long intergenic noncoding RNAs (lincRNAs) transcript variant on chromosome 12, was associated with DIH (p = 5.3 × 10(-7), OR = 5.4, 95% CI = 2.8-10.3). These genetic variants that are putatively associated with DIH due to ARV drugs alone and ARV-ATD co-treatment establish a foundation for future personalized medicine in people with HIV and TB and call for larger studies in independent populations.

PMID: 28388302 [PubMed - in process]

Defective Gpsm2/Gαi3 signalling disrupts stereocilia development and growth cone actin dynamics in Chudley-McCullough syndrome.

Nat Commun. 2017 Apr 07;8:14907

Authors: Mauriac SA, Hien YE, Bird JE, Carvalho SD, Peyroutou R, Lee SC, Moreau MM, Blanc JM, Geyser A, Medina C, Thoumine O, Beer-Hammer S, Friedman TB, Rüttiger L, Forge A, Nürnberg B, Sans N, Montcouquiol M

Abstract
Mutations in GPSM2 cause Chudley-McCullough syndrome (CMCS), an autosomal recessive neurological disorder characterized by early-onset sensorineural deafness and brain anomalies. Here, we show that mutation of the mouse orthologue of GPSM2 affects actin-rich stereocilia elongation in auditory and vestibular hair cells, causing deafness and balance defects. The G-protein subunit Gαi3, a well-documented partner of Gpsm2, participates in the elongation process, and its absence also causes hearing deficits. We show that Gpsm2 defines an ∼200 nm nanodomain at the tips of stereocilia and this localization requires the presence of Gαi3, myosin 15 and whirlin. Using single-molecule tracking, we report that loss of Gpsm2 leads to decreased outgrowth and a disruption of actin dynamics in neuronal growth cones. Our results elucidate the aetiology of CMCS and highlight a new molecular role for Gpsm2/Gαi3 in the regulation of actin dynamics in epithelial and neuronal tissues.

PMID: 28387217 [PubMed - in process]

The Protective Effect of Aucubin from Eucommia ulmoides Against Status Epilepticus by Inducing Autophagy and Inhibiting Necroptosis.

Am J Chin Med. 2017 Apr 07;:1-17

Authors: Wang J, Li Y, Huang WH, Zeng XC, Li XH, Li J, Zhou J, Xiao J, Xiao B, Ouyang DS, Hu K

Abstract
Eucommia ulmoides Oliv. is a famous traditional Chinese medicine which exhibits anti-oxidative stress ability and neuro-protective effects. Aucubin is the predominant component of Eucommia ulmoides Oliv. Our present study is intended to investigate aucubin's potential protective effects on neurons against epilepsy in the hippocampus by establishing the lithium-pilocarpine induced status epilepticus (SE) rat model in vivo. Aucubin (at a low dose and a high dose of 5[Formula: see text]mg/kg and 10[Formula: see text]mg/kg, respectively) was administered through gavage for two weeks before lithium-pilocarpine injection. Rats were sacrificed at 4, 24 and 72[Formula: see text]h after SE induction. Pretreatment with both low-dose and high-dose aucubin significantly reduced the number of death neurons ([Formula: see text]) and increased the number of surviving neurons ([Formula: see text]) in DG, Hilus, CA1 and CA3 hippocampal regions post SE. Meanwhile, it significantly inhibited necroptosis proteins (MLKL and RIP-1) ([Formula: see text] or [Formula: see text]) and enhanced autophagy protein (Beclin-1 and LC3BII/LC3BI) prevalence in the hippocampus ([Formula: see text] or [Formula: see text]). In conclusion, aucubin appeared to ameliorate damages in lithium-pilocarpine induced SE in hippocampus, reduce the number of apoptotic neurons, and increased the number of survival neurons by inducing autophagy and inhibiting necroptosis. These original findings might provide an important basis for the further investigation of the therapeutic role of aucubin in treatment or prevention of epilepsy-related neuronal damages.

PMID: 28387136 [PubMed - as supplied by publisher]

Activation of the ventral tegmental area increased wakefulness in mice.

Sleep Biol Rhythms. 2017;15(2):107-115

Authors: Sun HX, Wang DR, Ye CB, Hu ZZ, Wang CY, Huang ZL, Yang SR

Abstract
The ventral tegmental area (VTA) is crucial for brain functions, such as voluntary movement and cognition; however, the role of VTA in sleep-wake regulation when directly activated or inhibited remains unknown. In this study, we investigated the effects of activation or inhibition of VTA neurons on sleep-wake behavior using the pharmacogenetic "designer receptors exclusively activated by designer drugs (DREADD)" approach. Immunohistochemistry staining was performed to confirm the microinjection sites, and combined with electrophysiological experiments, to determine whether the VTA neurons were activated or inhibited. The hM3Dq-expressing VTA neurons were excited confirmed by clozapine-N-oxide (CNO)-driven c-Fos expression and firing in patch-clamp recordings; whereas the hM4Di-expressing VTA neurons inhibited by reduction of firing. Compared with controls, the activation of VTA neurons at 9:00 (inactive period) produced a 120.1% increase in the total wakefulness amount for 5 h, whereas NREM and REM sleep were decreased by 62.5 and 92.2%, respectively. Similarly, when VTA neurons were excited at 21:00 (active period), the total wakefulness amount increased 81.5%, while NREM and REM sleep decreased 64.6 and 93.8%, respectively, for 8 h. No difference of the amount and EEG power density of the NREM sleep was observed following the arousal effects of CNO. The inhibition of VTA neurons during active or inactive periods gave rise to no change in the time spent in the wakefulness, REM, and NREM sleep compared with control. The results indicated that VTA neurons activated pharmacogentically played important roles in promoting wakefulness.

PMID: 28386207 [PubMed - in process]

Upregulation of long noncoding RNA zinc finger antisense 1 enhances epithelial-mesenchymal transition in vitro and predicts poor prognosis in glioma.

Tumour Biol. 2017 Mar;39(3):1010428317695022

Authors: Lv QL, Chen SH, Zhang X, Sun B, Hu L, Qu Q, Huang YT, Wang GH, Liu YL, Zhang YY, Zhou HH

Abstract
Increasing evidence indicates that long noncoding RNAs play important roles in development and progression of various cancers. Zinc finger antisense 1 is a novel long noncoding RNA whose clinical significance, biological function, and underlying mechanism are still undetermined in glioma. In this study, we reported that zinc finger antisense 1 expression was markedly upregulated in glioma and tightly correlated with clinical stage. Moreover, patients with high zinc finger antisense 1 expression had shorter survival. Multivariate Cox regression analysis provided a clue that, probably, zinc finger antisense 1 level could serve as an independent prognostic factor for glioma. Functionally, zinc finger antisense 1 acted as an oncogene in glioma because its knockdown could promote apoptosis and significantly inhibit cell proliferation, migration, and invasion. Furthermore, zinc finger antisense 1 silencing could result in cell cycle arrest at the G0/G1 phase and correspondingly decrease the percentage of S phase cells in both U87 and U251 cell lines. Moreover, it was found that silenced zinc finger antisense 1 could impair migration and invasion by inhibiting the epithelial-mesenchymal transition through reducing the expression of MMP2, MMP9, N-cadherin, Integrin β1, ZEB1, Twist, and Snail as well as increasing E-cadherin level in glioma. Taken together, our data identified that zinc finger antisense 1 might act as a valuable prognostic biomarker and potential therapeutic target for glioma.

PMID: 28349823 [PubMed - indexed for MEDLINE]

Evidence for circulating cancer stem-like cells and epithelial-mesenchymal transition phenotype in the pleurospheres derived from lung adenocarcinoma using liquid biopsy.

Tumour Biol. 2017 Mar;39(3):1010428317695915

Authors: Mirza S, Jain N, Rawal R

Abstract
Lung cancer stem cells are supposed to be the main drivers of tumor initiation, maintenance, drug resistance, and relapse of the disease. Hence, identification of the cellular and molecular aspects of these cells is a prerequisite for targeted therapy of lung cancer. Currently, analysis of circulating tumor cells has the potential to become the main diagnostic technique to monitor disease progression or therapeutic response as it is non-invasive. However, accurate detection of circulating tumor cells has remained a challenge, as epithelial cell markers used so far are not always trustworthy for detecting circulating tumor cells, especially during epithelial-mesenchymal transition. As cancer stem cells are the only culprit to initiate metastatic tumors, our aim was to isolate and characterize circulating tumor stem cells rather than circulating tumor cells from the peripheral blood of NSCLC adenocarcinoma as limited data are available addressing the gene expression profiling of lung cancer stem cells. Here, we reveal that CD44(+)/CD24(-) population in circulation not only exhibit stem cell-related genes but also possess epithelial-mesenchymal transition characteristics. In conclusion, the use of one or more cancer stem cell markers along with epithelial, mesenchymal and epithelial mesenchymal transition markers will prospectively provide the most precise assessment of the threat for recurrence and metastatic disease and has a great potential for forthcoming applications in harvesting circulating tumor stem cells and their downstream applications. Our results will aid in developing diagnostic and prognostic modalities and personalized treatment regimens like dendritic cell-based immunotherapy that can be utilized for targeting and eliminating circulating tumor stem cells, to significantly reduce the possibility of relapse and improve clinical outcomes.

PMID: 28347243 [PubMed - indexed for MEDLINE]

Antioxidant polymorphisms do not influence the risk of epilepsy or its drug resistance after neonatal hypoxic-ischemic brain injury.

Seizure. 2017 Mar;46:38-42

Authors: Esih K, Goričar K, Dolžan V, Rener-Primec Z

Abstract
PURPOSE: The aim of this study was to investigate if common functional antioxidant polymorphisms are associated with epilepsy after neonatal hypoxic-ischemic encephalopathy (HIE). The antioxidant enzymes manganese superoxide dismutase (SOD2), glutathione peroxidase 1 (GPX1) and catalase (CAT) represent the primary defence mechanism against reactive oxygen species (ROS). Evidence suggests that genetic variants in antioxidant enzymes could influence susceptibility to epilepsy, but to date the relationship between them remains unclear.
METHODS: The study comprised 214 patients with epilepsy (64 with and 150 without neonatal HIE) as well as 95 healthy controls. Genomic DNA was isolated from buccal swabs or venous blood samples and genotyped for SOD2 rs4880, GPX1 rs1050450 and CAT rs1001179 using real-time PCR-based methods.
RESULTS: The investigated polymorphisms influenced neither the overall risk of epilepsy nor the risk of epilepsy after HIE in comparison with healthy controls. Furthermore, no significant difference in genotype distribution was observed between patients with drug-resistant epilepsy and patients in remission in either the group with epilepsy but without HIE or in the group with epilepsy and HIE, although the frequency of drug-resistant cases was higher in the latter group (p=0.009, OR=2.52; 95% CI=1.22-4.15).
CONCLUSION: According to this study, common GPX1, SOD2 and CAT polymorphisms do not influence the overall risk of epilepsy after HIE and its drug resistance.

PMID: 28222320 [PubMed - indexed for MEDLINE]

Critical evaluation of challenges and future use of animals in experimentation for biomedical research.

Int J Immunopathol Pharmacol. 2016 Dec;29(4):551-561

Authors: Singh VP, Pratap K, Sinha J, Desiraju K, Bahal D, Kukreti R

Abstract
Animal experiments that are conducted worldwide contribute to significant findings and breakthroughs in the understanding of the underlying mechanisms of various diseases, bringing up appropriate clinical interventions. However, their predictive value is often low, leading to translational failure. Problems like translational failure of animal studies and poorly designed animal experiments lead to loss of animal lives and less translatable data which affect research outcomes ethically and economically. Due to increasing complexities in animal usage with changes in public perception and stringent guidelines, it is becoming difficult to use animals for conducting studies. This review deals with challenges like poor experimental design and ethical concerns and discusses key concepts like sample size, statistics in experimental design, humane endpoints, economic assessment, species difference, housing conditions, and systematic reviews and meta-analyses that are often neglected. If practiced, these strategies can refine the procedures effectively and help translate the outcomes efficiently.

PMID: 27694614 [PubMed - indexed for MEDLINE]

Cross-Validation of High-Resolution Melting Analysis-Based Genotyping Platform.

Genet Test Mol Biomarkers. 2017 Apr;21(4):259-264

Authors: Langaee T, Stauffer L, Galloway C, Solayman MH, Cavallari L

Abstract
AIMS: Developing genetic and pharmacogenetic panels enhances genetic testing in clinical molecular diagnostics and precision medicine. This study was designed to cross-validate the performance of Canon's multiplex high-resolution DNA melting analysis platform with the Applied Biosystems TaqMan(®)-based Quant Studio Real-Time PCR System and Pyrosequencing(®) genotyping platforms for common genetic polymorphisms of the vitamin K epoxide reductase complex 1 (VKORC1) and CYP2C9.
MATERIALS AND METHODS: Genomic DNA isolated from 240 blood and saliva samples was used to genotype the VKORC1-1639 G/A (rs9923231), CYP2C9*2 (430C>T, rs28371674), and CYP2C9*3 (1075A>C, rs1057910) single-nucleotide polymorphisms (SNPs) on the three above-mentioned genotyping platforms.
RESULTS: There was 99.2%, 100%, and 100% concordance among the Canon DNA analyzer, the TaqMan-based QuantStudio, and the Pyrosequencing genotyping results for the VKORC1 (rs9923231), CYP2C9*2, and CYP2C9*3 SNPs, respectively, in DNA samples isolated from blood. The DNA samples isolated from saliva showed 100% concordance among the three test platforms for the three tested SNPs.
CONCLUSION: These results show that, the DNA analyzer performed very well when compared with two commonly used genotyping platforms. The reliability, multiple genetic variant testing capability, and short turnaround time for up to eight samples make the DNA analyzer an ideal genotyping platform for genetic testing in the clinical practice setting, where efficient genotyping is important to prevent delays in optimizing drug therapy.

PMID: 28384046 [PubMed - in process]

ABC Transport Proteins in Cardiovascular Disease-A Brief Summary.

Molecules. 2017 Apr 06;22(4):

Authors: Schumacher T, Benndorf RA

Abstract
Adenosine triphosphate (ATP)-binding cassette (ABC) transporters may play an important role in the pathogenesis of atherosclerotic vascular diseases due to their involvement in cholesterol homeostasis, blood pressure regulation, endothelial function, vascular inflammation, as well as platelet production and aggregation. In this regard, ABC transporters, such as ABCA1, ABCG5 and ABCG8, were initially found to be responsible for genetically-inherited syndromes like Tangier diseases and sitosterolemia. These findings led to the understanding of those transporter's function in cellular cholesterol efflux and thereby also linked them to atherosclerosis and cardiovascular diseases (CVD). Subsequently, further ABC transporters, i.e., ABCG1, ABCG4, ABCB6, ABCC1, ABCC6 or ABCC9, have been shown to directly or indirectly affect cellular cholesterol efflux, the inflammatory response in macrophages, megakaryocyte proliferation and thrombus formation, as well as vascular function and blood pressure, and may thereby contribute to the pathogenesis of CVD and its complications. Furthermore, ABC transporters, such as ABCB1, ABCC2 or ABCG2, may affect the safety and efficacy of several drug classes currently in use for CVD treatment. This review will give a brief overview of ABC transporters involved in the process of atherogenesis and CVD pathology. It also aims to briefly summarize the role of ABC transporters in the pharmacokinetics and disposition of drugs frequently used to treat CVD and CVD-related complications.

PMID: 28383515 [PubMed - in process]

SMAD-4 gene expression in human colorectal cancer: Comparison with some clinical and pathological parameters.

Pathol Res Pract. 2017 Jan;213(1):45-49

Authors: Wosiak A, Wodziński D, Kolasa M, Sałagacka-Kubiak A, Balcerczak E

Abstract
The aim of this study was to evaluate the expression of SMAD-4 gene in cases of colorectal cancer and to link the obtained data with the development of this disease. SMAD-4 gene is responsible for the control of many important cellular processes, for example prevention of excessive epithelial cell growth and divisions. This suppressor gene is located on chromosome 18 within the region with frequent genetic losses in colorectal cancer. Inactivation of this gene is commonly found in pancreatic cancer where the SMAD-4 gene lost in the expression has been associated with a poor prognosis in this cancer. However, the role of SMAD-4 gene in other cancers has not been completely explained, therefore in the present study we tried to find the role of this gene in colon cancer. The relative expression level of SMAD-4 gene was determined by real-time PCR for 80 cases of colorectal cancer. The obtained results for SMAD-4 expression were compared with many clinical and pathological variables (such as the size and depth of primary tumour penetration, presence of the metastases, stage of cancer, histological grade or overall survival). It was found that the level of SMAD-4 gene expression was not associated with the analyzed parameters of clinical staging. The lack of dependence can be caused by slight differences within the study group in view of parameters correlated with invasive colon cancer. Further analysis in this direction is needed.

PMID: 27914767 [PubMed - indexed for MEDLINE]

NAT2 variants are associated with drug-induced liver injury caused by anti-tuberculosis drugs in Indonesian patients with tuberculosis.

J Hum Genet. 2016 Jun;61(6):533-7

Authors: Yuliwulandari R, Susilowati RW, Wicaksono BD, Viyati K, Prayuni K, Razari I, Kristin E, Syafrizal, Subagyo, Sri Diana E, Setiawati S, Ariyani A, Mahasirimongkol S, Yanai H, Mushiroda T, Tokunaga K

Abstract
Drug-induced liver injury (DILI) is the most common adverse drug reaction in the treatment of tuberculosis (TB). Several studies showed that patients with TB and the slow-acetylator phenotype caused by NAT2 variants are highly susceptible to DILI caused by anti-TB drugs, hereafter designated AT-DILI. However, the role of NAT2 variants in AT-DILI has never been assessed for an Indonesian population. We recruited 50 patients with TB and AT-DILI and 191 patients with TB but without AT-DILI; we then used direct DNA sequencing to assess single-nucleotide polymorphisms in the coding region of NAT2. NAT2*6A was significantly associated with susceptibility to AT-DILI (P=7.7 × 10(-4), odds ratio (OR)=4.75 (1.8-12.55)). Moreover, patients with TB and the NAT2-associated slow-acetylator phenotype showed higher risk of AT-DILI than patients with the rapid- or intermediate-acetylator phenotypes (P=1.7 × 10(-4), OR=3.45 (1.79-6.67)). In conclusion, this study confirms the significance of the association between slow-acetylator NAT2 variants and susceptibility to AT-DILI in an Indonesian population.

PMID: 26911349 [PubMed - indexed for MEDLINE]

Genetic Polymorphisms in Organic Cation Transporter 1 Attenuates Hepatic Metformin Exposure in Humans.

Clin Pharmacol Ther. 2017 Apr 05;:

Authors: Sundelin EI, Gormsen LC, Jensen JB, Vendelbo MH, Jakobsen S, Munk OL, Christensen MM, Brøsen K, Frøkiaer J, Jessen N

Abstract
Metformin has been used successfully to treat type 2 diabetes for decades. However, the efficacy of the drug varies considerably from patient to patient and this may in part be due to its pharmacokinetic properties. The aim of this study was to examine if common polymorphisms in SLC22A1, encoding the transporter protein OCT1, affect the hepatic distribution of metformin in humans. We performed non-invasive (11) C-metformin PET/CT to determine hepatic exposure in 12 subjects genotyped for variants in SLC22A1. Hepatic distribution of metformin was significantly reduced after oral intake in carriers of M420del and R61C variants in SLC22A1 without being associated with changes in circulating levels of metformin. Our data show that genetic polymorphisms in transporter proteins cause variation in hepatic exposure to metformin, and it demonstrates the application of novel imaging techniques to investigate pharmacogenetic properties in humans. This article is protected by copyright. All rights reserved.

PMID: 28380657 [PubMed - as supplied by publisher]

Worldwide distribution of cytochrome P450 alleles: A meta-analysis of population-scale sequencing projects.

Clin Pharmacol Ther. 2017 Apr 05;:

Authors: Zhou Y, Ingelman-Sundberg M, Lauschke VM

Abstract
Genetic polymorphisms in cytochrome P450 (CYP) genes can result in altered metabolic activity towards a plethora of clinically important medications. Thus, single nucleotide variants and copy number variations in CYP genes are major determinants of drug pharmacokinetics and toxicity and constitute pharmacogenetic biomarkers for drug dosing, efficacy and safety. Strikingly, the distribution of CYP alleles differs considerably between populations with important implications for personalized drug therapy and healthcare programs. To provide a global distribution map of CYP alleles with clinical importance, we integrated whole-genome and exome sequencing data from 56,945 unrelated individuals of five major human populations. By combining this data set with population-specific linkage information, we derive the frequencies of 176 CYP haplotypes, providing an extensive resource for major genetic determinants of drug metabolism. Furthermore, we aggregated this data set into spectra of predicted functional variability in the respective populations and discuss the implications for population-adjusted pharmacological treatment strategies. This article is protected by copyright. All rights reserved.

PMID: 28378927 [PubMed - as supplied by publisher]

Vitamin Pharmacogenomics: New Insight into Individual Differences in Diseases and Drug Responses.

Genomics Proteomics Bioinformatics. 2017 Apr 01;:

Authors: He HY, Liu MZ, Zhang YL, Zhang W

Abstract
Vitamins are vital to sustain normal physiological function, metabolism, and growth for all living organisms. Being an integral component of coenzyme, vitamins can affect the catalytic activities of many enzymes and the expression of drug transporters. Genetic variations in metabolism and/or transporter genes of drugs can influence the exposure of the human body to drugs and/or their active metabolites, thus contributing to the variations in drug responses and toxicities. Nonetheless, pharmacogenomics studies on nutrients have been rarely summarized. In this article, we reviewed recent progress on vitamin pharmacogenomics, for a better understanding on the influence of vitamin-related gene polymorphisms on inter-individual differences in diseases and drug efficacy and safety.

PMID: 28377107 [PubMed - as supplied by publisher]

Influence of arginase polymorphisms and arginase levels/activity on the response to erectile dysfunction therapy with sildenafil.

Pharmacogenomics J. 2017 Apr 04;:

Authors: Lacchini R, Muniz JJ, Nobre YT, Cologna AJ, Martins AC, Tanus-Santos JE

Abstract
Arginase 1 (ARG1) and arginase 2 (ARG2) compete with nitric oxide synthases for the substrate l-arginine. Here we aim to assess whether arginase 1 and 2 plasma levels, plasma arginase activity or genetic factors are associated with altered responsiveness to sildenafil. We studied 71 post-prostatectomy erectile dysfunction (ED) patients (PED group) and 72 clinical ED patients (CED). Patients responded to the International Index of Erectile Function questionnaire before and after the treatment. We found positive and negative correlations between plasma levels of arginase 1 and sildenafil responsiveness in the PED and CED groups, respectively. PED group also presented negative correlation between plasma arginase activity and sildenafil responsiveness. Sildenafil poor responders have shown higher plasma arginase activity in PED and higher arginase 1 levels on CED groups. In addition, variant genotypes for the rs2781659, rs2781667 and rs17599586 polymorphisms were associated with reduced arginase activity, as well as the GTTT ARG1 haplotype in CED group.The Pharmacogenomics Journal advance online publication, 4 April 2017; doi:10.1038/tpj.2017.2.

PMID: 28374859 [PubMed - as supplied by publisher]

Sulfotransferase 1A3/4 copy number variation is associated with neurodegenerative disease.

Pharmacogenomics J. 2017 Apr 04;:

Authors: Butcher NJ, Horne MK, Mellick GD, Fowler CJ, Masters CL, AIBL research group, Minchin RF

Abstract
The cytosolic aryl sulfotransferase genes SULT1A3 and SULT1A4 are located on chromosome 16p11.2 in a region of chromosomal instability. SULT1A3/4 are important enzymes in the metabolism of catecholamines linked to neurodegenerative diseases such as Parkinson's and Alzheimer's. In the present study, copy number variation of the SULT1A3/4 genes in healthy individuals, as well as a cohort of Parkinson's disease and Alzheimer's disease patients was examined. In all subjects, SULT1A3/4 copy number varied from 1 to 10. In Alzheimer's disease patients, there was a significantly lower copy number compared to controls, and a positive correlation between copy number and age of disease onset. By contrast, there were no differences in Parkinson's disease patients. However, when early-onset Parkinson's disease was evaluated separately, there appeared to be an association with gene copy number and risk. The current study shows that these neurodegenerative diseases may be related to SULT1A3/4 copy number.The Pharmacogenomics Journal advance online publication, 4 April 2017; doi:10.1038/tpj.2017.4.

PMID: 28374858 [PubMed - as supplied by publisher]

The Role of Pharmacogenetics in Chronic Plaque Psoriasis: Update of the Literature.

Mol Diagn Ther. 2017 Apr 03;:

Authors: Talamonti M, D'Adamio S, Bianchi L, Galluzzo M

Abstract
Psoriasis is a chronic inflammatory disease triggered by both genetic and environmental factors. Systemic and biologic therapies used to treat moderate-to-severe psoriasis show significant variability in efficacy, are associated with various degrees of toxicity, and, for biologic therapies, are expensive. There is a great need for non-invasive biomarkers to predict treatment outcomes of these therapies and to individualize care for patients with psoriasis. This article reviews currently recognized pharmacogenetic targets related to the treatment of chronic plaque psoriasis, in particular to biologic therapies. The use of pharmacogenetic and pharmacogenomic approaches to genetically profile patients will allow therapies to be targeted more precisely and safely to individual patients, to optimize the treatment of psoriasis, and minimize unnecessary costs. Characterizing patients with psoriasis according to common molecular mechanisms rather than by clinical phenotype may also allow more selective therapeutic agents to be targeted to genetically distinct groups of patients.

PMID: 28374122 [PubMed - as supplied by publisher]