Pharmacogenomics
Variability of the Genes Involved in the Cellular Redox Status and Their Implication in Drug Hypersensitivity Reactions
Antioxidants (Basel). 2021 Feb 15;10(2):294. doi: 10.3390/antiox10020294.
ABSTRACT
Adverse drug reactions are a major cause of morbidity and mortality. Of the great diversity of drugs involved in hypersensitivity drug reactions, the most frequent are non-steroidal anti-inflammatory drugs followed by β-lactam antibiotics. The redox status regulates the level of reactive oxygen and nitrogen species (RONS). RONS interplay and modulate the action of diverse biomolecules, such as inflammatory mediators and drugs. In this review, we address the role of the redox status in the initiation, as well as in the resolution of inflammatory processes involved in drug hypersensitivity reactions. We summarize the association findings between drug hypersensitivity reactions and variants in the genes that encode the enzymes related to the redox system such as enzymes related to glutathione: Glutathione S-transferase (GSTM1, GSTP, GSTT1) and glutathione peroxidase (GPX1), thioredoxin reductase (TXNRD1 and TXNRD2), superoxide dismutase (SOD1, SOD2, and SOD3), catalase (CAT), aldo-keto reductase (AKR), and the peroxiredoxin system (PRDX1, PRDX2, PRDX3, PRDX4, PRDX5, PRDX6). Based on current evidence, the most relevant candidate redox genes related to hypersensitivity drug reactions are GSTM1, TXNRD1, SOD1, and SOD2. Increasing the understanding of pharmacogenetics in drug hypersensitivity reactions will contribute to the development of early diagnostic or prognosis tools, and will help to diminish the occurrence and/or the severity of these reactions.
PMID:33672092 | DOI:10.3390/antiox10020294
<em>Cannabis</em>-Based Oral Formulations for Medical Purposes: Preparation, Quality and Stability
Pharmaceuticals (Basel). 2021 Feb 22;14(2):171. doi: 10.3390/ph14020171.
ABSTRACT
Current legislation in Italy provides that medical Cannabis may be administered orally or by inhalation. One of the fundamental criteria for the administration of oral formulations is that they deliver a known consistent quantity of the active ingredients to ensure uniform therapies leading to the optimisation of the risks/benefits. In 2018, our group developed an improved Cannabis oil extraction technique. The objective of the present work was to carry out a stability study for the oil extracts obtained by this method. Furthermore, in order to facilitate the consumption of the prescribed medical Cannabis therapy by patients, a standard procedure was defined for the preparation of a single-dose preparation for oral use (hard capsules) containing the oil extract; thereafter, the quality and stability were evaluated. The hard capsules loaded with the oil extract were analysed and found to be uniform in content. The encapsulation process did not alter the quantity of the active molecule present in the oil. The stability tests yielded excellent results. Since the capsule dosage form is easily transported and administered, has pleasant organoleptic properties and is stable at room temperature for extended periods of time, this would facilitate the adherence to therapy by patients in treatment.
PMID:33671760 | DOI:10.3390/ph14020171
The FDA-Approved Antiviral Raltegravir Inhibits Fascin1-Dependent Invasion of Colorectal Tumor Cells In Vitro and In Vivo
Cancers (Basel). 2021 Feb 18;13(4):861. doi: 10.3390/cancers13040861.
ABSTRACT
BACKGROUND: Fascin1 is the key actin-bundling protein involved in cancer invasion and metastasis whose expression is associated with bad prognosis in tumor from different origins.
METHODS: In the present study, virtual screening (VS) was performed for the search of Fascin1 inhibitors and RAL, an FDA-approved inhibitor of human immunodeficiency virus-1 (HIV-1) integrase, was identified as a potential Fascin1 inhibitor. Biophysical techniques including nuclear magnetic resonance (NMR) and differential scanning fluorimetry (DSF) were carried out in order to confirm RAL as a Fascin1 blocker. The effect of RAL on actin-bundling activity Fascin1 was assessed by transmission electron microscopy (TEM), immunofluorescence, migration, and invasion assays on two human colorectal adenocarcinoma cell lines: HCT-116 and DLD-1. In addition, the anti-metastatic potential of RAL was in vivo evaluated by using the zebrafish animal model.
RESULTS: NMR and DSF confirmed in silico predictions and TEM demonstrated the RAL-induced disorganization of the actin structure compared to control conditions. The protrusion of lamellipodia in cancer cell line overexpressing Fascin1 (HCT-116) was abolished in the presence of this drug. By following the addition of RAL, migration of HCT-116 and DLD-1 cell lines was significantly inhibited. Finally, using endogenous and exogenous models of Fascin1 expression, the invasive capacity of colorectal tumor cells was notably impaired in the presence of RAL in vivo assays; without undesirable cytotoxic effects.
CONCLUSION: The current data show the in vitro and in vivo efficacy of the antiretroviral drug RAL in inhibiting human colorectal cancer cells invasion and metastasis in a Fascin1-dependent manner.
PMID:33670655 | DOI:10.3390/cancers13040861
Multicompartmental Lipopolyplex as Vehicle for Antigens and Genes Delivery in Vaccine Formulations
Pharmaceutics. 2021 Feb 19;13(2):281. doi: 10.3390/pharmaceutics13020281.
ABSTRACT
Vector design and its characterization is an area of great interest in current vaccine research. In this article, we have formulated and characterized a multicompartmental lipopolyplex, which associates multiple liposomes and polyplexes in the same complex. These particles allow the simultaneous delivery of lipid or water-soluble antigens associated with genes to the same cell, in much higher amounts than conventional lipopolyplexes. The vector characterization and optimization were carried out using liposomes with entrapped carboxyfluorescein and adapted electrophoretic assays. Two types of lipopolyplexes (containing hydrophilic or lipophilic antigens) were employed to evaluate their interest in vaccination. The lipopolyplex loaded with an extract of water-soluble melanoma proteins proved to efficiently induce humoral response in murine melanoma model, increasing the levels of IgM and IgG. The specificity of the immune response induced by the lipopolyplex was demonstrated in mice with the lipopolyplex containing the GD3 ganglioside lipid antigen, abundant in melanoma cells. The levels of anti-GD3 IgG increased markedly without modifying the expression of humoral antibodies against other gangliosides.
PMID:33669785 | DOI:10.3390/pharmaceutics13020281
Pharmacogenomic Profile and Adverse Drug Reactions in a Prospective Therapeutic Cohort of Chagas Disease Patients Treated with Benznidazole
Int J Mol Sci. 2021 Feb 16;22(4):1960. doi: 10.3390/ijms22041960.
ABSTRACT
Chagas disease remains a major social and public health problem in Latin America. Benznidazole (BZN) is the main drug with activity against Trypanosoma cruzi. Due to the high number of adverse drug reactions (ADRs), BZN is underprescribed. The goal of this study was to evaluate the genetic and transcriptional basis of BZN adverse reactions.
METHODS: A prospective cohort with 102 Chagas disease patients who underwent BZN treatment was established to identify ADRs and understand their genetic basis. The patients were classified into two groups: those with at least one ADR (n = 73), and those without ADRs (n = 29). Genomic analyses were performed comparing single nucleotide polymorphisms between groups. Transcriptome data were obtained comparing groups before and after treatment, and signaling pathways related to the main ADRs were evaluated.
RESULTS: A total of 73 subjects (71.5%) experienced ADRs. Dermatological symptoms were most frequent (45.1%). One region of chromosome 16, at the gene LOC102724084 (rs1518601, rs11861761, and rs34091595), was associated with ADRs (p = 5.652 × 10-8). Transcriptomic data revealed three significantly enriched signaling pathways related to BZN ADRs.
CONCLUSIONS: These data suggest that part of adverse BZN reactions might be genetically determined and may facilitate patient risk stratification prior to starting BZN treatment.
PMID:33669428 | DOI:10.3390/ijms22041960
Common Treatment, Common Variant: Evolutionary Prediction of Functional Pharmacogenomic Variants
J Pers Med. 2021 Feb 16;11(2):131. doi: 10.3390/jpm11020131.
ABSTRACT
Pharmacogenomics holds the promise of personalized drug efficacy optimization and drug toxicity minimization. Much of the research conducted to date, however, suffers from an ascertainment bias towards European participants. Here, we leverage publicly available, whole genome sequencing data collected from global populations, evolutionary characteristics, and annotated protein features to construct a new in silico machine learning pharmacogenetic identification method called XGB-PGX. When applied to pharmacogenetic data, XGB-PGX outperformed all existing prediction methods and identified over 2000 new pharmacogenetic variants. While there are modest pharmacogenetic allele frequency distribution differences across global population samples, the most striking distinction is between the relatively rare putatively neutral pharmacogene variants and the relatively common established and newly predicted functional pharamacogenetic variants. Our findings therefore support a focus on individual patient pharmacogenetic testing rather than on clinical presumptions about patient race, ethnicity, or ancestral geographic residence. We further encourage more attention be given to the impact of common variation on drug response and propose a new 'common treatment, common variant' perspective for pharmacogenetic prediction that is distinct from the types of variation that underlie complex and Mendelian disease. XGB-PGX has identified many new pharmacovariants that are present across all global communities; however, communities that have been underrepresented in genomic research are likely to benefit the most from XGB-PGX's in silico predictions.
PMID:33669176 | DOI:10.3390/jpm11020131
Response and Toxicity to Cytarabine Therapy in Leukemia and Lymphoma: From Dose Puzzle to Pharmacogenomic Biomarkers
Cancers (Basel). 2021 Feb 25;13(5):966. doi: 10.3390/cancers13050966.
ABSTRACT
Cytarabine is a pyrimidine nucleoside analog, commonly used in multiagent chemotherapy regimens for the treatment of leukemia and lymphoma, as well as for neoplastic meningitis. Ara-C-based chemotherapy regimens can induce a suboptimal clinical outcome in a fraction of patients. Several studies suggest that the individual variability in clinical response to Leukemia & Lymphoma treatments among patients, underlying either Ara-C mechanism resistance or toxicity, appears to be associated with the intracellular accumulation and retention of Ara-CTP due to genetic variants related to metabolic enzymes. Herein, we reported (a) the latest Pharmacogenomics biomarkers associated with the response to cytarabine and (b) the new drug formulations with optimized pharmacokinetics. The purpose of this review is to provide readers with detailed and comprehensive information on the effects of Ara-C-based therapies, from biological to clinical practice, maintaining high the interest of both researcher and clinical hematologist. This review could help clinicians in predicting the response to cytarabine-based treatments.
PMID:33669053 | DOI:10.3390/cancers13050966
Dual 2-Hydroxypropyl-β-Cyclodextrin and 5,10,15,20-Tetrakis (4-Hydroxyphenyl) Porphyrin System as a Novel Chiral-Achiral Selector Complex for Enantioseparation of Aminoalkanol Derivatives with Anticancer Activity in Capillary Electrophoresis
Molecules. 2021 Feb 13;26(4):993. doi: 10.3390/molecules26040993.
ABSTRACT
In this study, a complex consisting of 2-hydroxypropyl-β-cyclodextrin and 5,10,15,20-tetrakis (4-hydroxyphenyl) porphyrin, (named dual chiral-achiral selector complex) was used for the determination of two novel potential anticancer agents of (I) and (II) aminoalkanol derivatives. This work aimed at developing an effective method that can be utilized for the determination of I (S), I (R), and II (S) and II (R) enantiomers of (I) and (II) compounds through the use of a dual chiral-achiral selector complex consisting of hydroxypropyl-β-cyclodextrin and 5,10,15,20-tetrakis (4-hydroxyphenyl) porphyrin system by applying capillary electrophoresis. This combination proved to be beneficial in achieving high separation selectivity due to the combined effects of different modes of chiral discrimination. The enantiomers of (I) and (II) compounds were separated within a very short time of 3.6-7.2 min, in pH 2.5 phosphate buffer containing 2-hydroxypropyl-β-cyclodextrin and 5,10,15,20-tetrakis (4-hydroxyphenyl) porphyrin system at a concentration of 5 and 10 mM, respectively, at 25 °C and +10 kV. The detection wavelength of the detector was set at 200 nm. The LOD for I (S), I (R), II (S), and II (R) was 65.2, 65.6, 65.1, and 65.7 ng/mL, respectively. LOQ for I (S), I (R), II (S), and II (R) was 216.5, 217.8, 217.1, and 218.1 ng/mL, respectively. Recovery was 94.9-99.9%. The repeatability and reproducibility of the method based on the values of the migration time, and the area under the peak was 0.3-2.9% RSD. The stability of the method was determined at 0.1-4.9% RSD. The developed method was used in the pilot studies for determining the enantiomers I (S), I (R), II (S), and II (R) in the blood serum.
PMID:33668491 | DOI:10.3390/molecules26040993
Outcomes of Individuals With and Without Heart Failure Presenting With Acute Coronary Syndrome
Am J Cardiol. 2021 Mar 2:S0002-9149(21)00202-2. doi: 10.1016/j.amjcard.2021.02.027. Online ahead of print.
ABSTRACT
Major adverse cardiac event (MACE) and bleeding risks following percutaneous coronary intervention (PCI) for acute coronary syndromes (ACS) are not well defined in individuals with heart failure (HF). We followed 1,145 individuals in the Pharmacogenomic Resource to improve Medication Effectiveness Genotype Guided Antiplatelet Therapy cohort for MACE and bleeding events following PCI for ACS. We constructed Cox proportional hazards models to compare MACE and bleeding in those with vs. without HF, adjusting for sociodemographics, comorbidities, and medications. We also determined predictors of MACE and bleeding events in both groups. 370 (32%) individuals did and 775 (68%) did not have HF prior to PCI. Mean age was 61.7 ± 12.2 years, 31% were female, and 24% were African American. After a median follow-up of 0.78 years, individuals with HF had higher rates of MACE compared to those without HF (48 vs. 24 events per 100 person years) which remained significant after multivariable adjustment (hazard ratio [HR] 1.31, 95% confidence interval [CI] 1.00-1.72). Similarly, bleeding was higher in those with vs. without HF (22 vs. 11 events per 100 person years), although this was no longer statistically significant after multivariable adjustment (HR 1.29, 95% CI 0.86-1.93). Diabetes and peripheral vascular disease were predictors of MACE, and ESRD was a predictor of bleeding among participants with HF. MACE risk is higher in individuals with vs. without HF following PCI for ACS. However, the risk of bleeding, especially among those with ESRD, must be considered when determining post-PCI anticoagulant strategies.
PMID:33667441 | DOI:10.1016/j.amjcard.2021.02.027
Tribute to Professor Hartmut Derendorf - 1953 to 2020: Driving force in Clinical Pharmacology and Mentor Extraordinaire
Clin Pharmacol Ther. 2021 Mar 5. doi: 10.1002/cpt.2193. Online ahead of print.
NO ABSTRACT
PMID:33667324 | DOI:10.1002/cpt.2193
Drug Interactions with Antihypertensives
Curr Hypertens Rep. 2021 Mar 5;23(3):14. doi: 10.1007/s11906-021-01131-y.
ABSTRACT
PURPOSE OF REVIEW: Hypertension is remarkably prevalent, affecting an estimated 1.13 billion people worldwide. It often requires the use of multi-drug regimens and is commonly associated with a myriad of other comorbidities which increase medication use. The pervasive use of antihypertensive medications combined with the presence of polypharmacy in many hypertensive patients results in significant risk of drug interactions. This review will summarize the relevant literature to assist clinicians in mitigating drug interaction risks when prescribing antihypertensives.
RECENT FINDINGS: Pharmacokinetic interactions affect drug disposition in the body and can occur at the steps of absorption, distribution, metabolism, or elimination of involved medications. Data has established the calcium channel blockers, namely, diltiazem and verapamil, as potent inhibitors of CYP3A4, and the majority of significant drug interactions involving antihypertensives are attributable to these two agents. Although less common, pharmacokinetic drug interactions with other antihypertensive classes have also been identified. Pharmacodynamic drug interactions with antihypertensives lead to synergy or antagonism of blood pressure lowering effects and can increase or mitigate adverse effects depending on the agents involved. Knowledge is emerging about drug-induced phenoconversion, a phenomenon whereby a drug interaction results in a drug metabolizing phenotype that is different than that predicted by an individual's genotype. Antihypertensive use in patients with comorbidities and polypharmacy increases the likelihood of encountering important drug-drug interactions. Dedicated efforts to better understand the relationship between pharmacokinetic drug interactions and pharmacogenomic information is important to advance efforts related to personalized medicine.
PMID:33666764 | DOI:10.1007/s11906-021-01131-y
Developing a gene panel for pharmacoresistant epilepsy: a review of epilepsy pharmacogenetics
Pharmacogenomics. 2021 Mar 5. doi: 10.2217/pgs-2020-0145. Online ahead of print.
ABSTRACT
Evaluating genes involved in the pharmacodynamics and pharmacokinetics of epilepsy drugs is critical to better understand pharmacoresistant epilepsy. We reviewed the pharmacogenetics literature on six antiseizure medicines (carbamazepine, perampanel, lamotrigine, levetiracetam, sodium valproate and zonisamide) and compared the genes found with those present on epilepsy gene panels using a functional annotation pathway analysis. Little overlap was found between the two gene lists; pharmacogenetic genes are mainly involved in detoxification processes, while epilepsy panel genes are involved in cell signaling and gene expression. Our work provides support for a specific pharmacoresistant epilepsy gene panel to assist antiseizure medicine selection, enabling personalized approaches to treatment. Future efforts will seek to include this panel in genomic analyses of pharmacoresistant patients, to determine clinical utility and patient treatment responses.
PMID:33666520 | DOI:10.2217/pgs-2020-0145
Predictive Biomarkers and Clinical Evidence
Basic Clin Pharmacol Toxicol. 2021 Mar 4. doi: 10.1111/bcpt.13578. Online ahead of print.
ABSTRACT
Predictive biomarkers play an important role in our efforts to individualize pharmacotherapy and within recent years, a number of different types of assays have been introduced. These biomarkers may potentially support the selection and dosage of specific drugs in order to maximize efficacy and minimize adverse reactions in the individual patient. However, in many instances, the scientific and clinical evidence is insufficient to support the prescribing decision. When predictive biomarkers are used to guide pharmacotherapy, it is important to secure that decisions are based on solid clinical evidence. Here, the regulatory authorities, especially the FDA have been at the forefront in relation to regulate this type of biomarker assay in order to secure patient safety. The approval process for companion diagnostics is an example of this effort, where the scientific validity of the biomarker and assay is in focus. With the approaching implementation of the new IVD Regulation, greater attention will also be paid to analytical and clinical validity of biomarker assays in the EU. For any type of predictive biomarker assay, including pharmacogenetic and tumour profiling tests, the clinical evidence needs to be in place before they are used routinely in the clinic.
PMID:33665955 | DOI:10.1111/bcpt.13578
Artificial increase of uracilemia during fluoropyrimidine treatment can lead to DPD deficiency misinterpretation
Ann Oncol. 2021 Mar 1:S0923-7534(21)00160-5. doi: 10.1016/j.annonc.2021.02.020. Online ahead of print.
NO ABSTRACT
PMID:33662499 | DOI:10.1016/j.annonc.2021.02.020
Cutting-edge genetics in obsessive-compulsive disorder
Fac Rev. 2020 Dec 23;9:30. doi: 10.12703/r/9-30. eCollection 2020.
ABSTRACT
This article reviews recent advances in the genetics of obsessive-compulsive disorder (OCD). We cover work on the following: genome-wide association studies, whole-exome sequencing studies, copy number variation studies, gene expression, polygenic risk scores, gene-environment interaction, experimental animal systems, human cell models, imaging genetics, pharmacogenetics, and studies of endophenotypes. Findings from this work underscore the notion that the genetic architecture of OCD is highly complex and shared with other neuropsychiatric disorders. Also, the latest evidence points to the participation of gene networks involved in synaptic transmission, neurodevelopment, and the immune and inflammatory systems in this disorder. We conclude by highlighting that further study of the genetic architecture of OCD, a great part of which remains to be elucidated, could benefit the development of diagnostic and therapeutic approaches based on the biological basis of the disorder. Studies to date revealed that OCD is not a simple homogeneous entity, but rather that the underlying biological pathways are variable and heterogenous. We can expect that translation from bench to bedside, through continuous effort and collaborative work, will ultimately transform our understanding of what causes OCD and thus how best to treat it.
PMID:33659962 | PMC:PMC7886082 | DOI:10.12703/r/9-30
<em>In vitro</em> Differentiation of Human iPSC-derived Cardiovascular Progenitor Cells (iPSC-CVPCs)
Bio Protoc. 2020 Sep 20;10(18):e3755. doi: 10.21769/BioProtoc.3755. eCollection 2020 Sep 20.
ABSTRACT
Induced pluripotent stem cell derived cardiovascular progenitor cells (iPSC-CVPCs) provide an unprecedented platform for examining the molecular underpinnings of cardiac development and disease etiology, but also have great potential to play pivotal roles in the future of regenerative medicine and pharmacogenomic studies. Biobanks like iPSCORE ( Stacey et al., 2013 ; Panopoulos et al., 2017 ), which contain iPSCs generated from hundreds of genetically and ethnically diverse individuals, are an invaluable resource for conducting these studies. Here, we present an optimized, cost-effective and highly standardized protocol for large-scale derivation of human iPSC-CVPCs using small molecules and purification using metabolic selection. We have successfully applied this protocol to derive iPSC-CVPCs from 154 different iPSCORE iPSC lines obtaining large quantities of highly pure cardiac cells. An important component of our protocol is Cell confluency estimates (ccEstimate), an automated methodology for estimating the time when an iPSC monolayer will reach 80% confluency, which is optimal for initiating iPSC-CVPC derivation, and enables the protocol to be readily used across iPSC lines with different growth rates. Moreover, we showed that cellular heterogeneity across iPSC-CVPCs is due to varying proportions of two distinct cardiac cell types: cardiomyocytes (CMs) and epicardium-derived cells (EPDCs), both of which have been shown to have a critical function in heart regeneration. This protocol eliminates the need of iPSC line-to-line optimization and can be easily adapted and scaled to high-throughput studies or to generate large quantities of cells suitable for regenerative medicine applications.
PMID:33659414 | PMC:PMC7853936 | DOI:10.21769/BioProtoc.3755
Expansion of Knowledge on OCT1 Variant Activity <em>In Vitro</em> and <em>In Vivo</em> Using Oct1/2<sup>-/-</sup> Mice
Front Pharmacol. 2021 Feb 15;12:631793. doi: 10.3389/fphar.2021.631793. eCollection 2021.
ABSTRACT
The role of organic cation transporter 1 (OCT1) in humans is gaining attention as data emerges regarding its role in physiology, drug exposure, and drug response. OCT1 variants with decreased in vitro function correlate well with altered exposure of multiple OCT1 substrates in variant carriers. In the current research, we investigate mechanisms behind activity of OCT1 variants in vitro by generating cell lines expressing known OCT1 variants and quantifying membrane OCT1 protein expression with corresponding OCT1 activity and kinetics. Oct knockout mice have provided additional insight into the role of Oct1 in the liver and have reproduced effects of altered OCT1 activity observed in the clinic. To assess the complex effect of Oct1 depletion on pharmacokinetics of prodrug proguanil and its active moiety cycloguanil, both of which are OCT1 substrates, Oct1/2-/- mice were used. Decreased membrane expression of OCT1 was demonstrated for all variant cell lines, although activity was substrate-dependent, as reported previously. Lack of change in activity for OCT1*2 resulted in increased intrinsic activity per pmol of OCT1 protein, particularly for sumatriptan but also for proguanil and cycloguanil. Similar to that reported in humans with decreased OCT1 function, systemic exposure of proguanil was minimally affected in Oct1/2-/- mice. However, proguanil liver partitioning and exposure decreased. Cycloguanil exposure decreased following proguanil administration in Oct1/2-/- mice, as did the systemic metabolite:parent ratio. When administered directly, systemic exposure of cycloguanil decreased slightly; however liver partitioning and exposure were decreased in Oct1/2-/- mice. Unexpectedly, following proguanil administration, the metabolite ratio in the liver changed only minimally, and liver partitioning of cycloguanil was affected in Oct1/2-/- mice to a lesser extent following proguanil administration than direct administration of cycloguanil. In conclusion, these in vitro and in vivo data offer additional complexity in understanding mechanisms of OCT1 variant activity as well as the effects of these variants in vivo. From cell lines, it is apparent that intrinsic activity is not directly related to OCT1 membrane expression. Additionally, in situations with a more complicated role of OCT1 in drug pharmacokinetics there is difficulty translating in vivo impact simply from intrinsic activity from cellular data.
PMID:33658943 | PMC:PMC7917185 | DOI:10.3389/fphar.2021.631793
Diffusion Mechanism Modeling of Metformin in Human Organic Cationic Amino Acid Transporter one and Functional Impact of S189L, R206C, and G401S Mutation
Front Pharmacol. 2021 Feb 9;11:587590. doi: 10.3389/fphar.2020.587590. eCollection 2020.
ABSTRACT
Metformin used as a first-line drug to treat Type 2 Diabetes Mellitus is transported via organic cation channels to soft tissues. Mutations in the SLC22A1 gene, such as Gly401Ser, Ser189Leu, and Arg206Cys, may affect the drug's therapeutic effect on these patients. This study aims at proposing a potential structural model for drug interactions with the hOCT1 transporter, as well as the impact of these mutations at both topological and electronic structure levels on the channel's surface, from a chemical point of view with, in addition to exploring the frequency distribution. To chemically understand metformin diffusion, we used an open model from the protein model database, with ID PM0080367, viewed through UCSF Chimera. The effect of the mutations was assessed using computational hybrid Quantum Mechanics/Molecular Mechanics, based on the Austin Model 1 semi-empirical method using Spartan 18' software. The results demonstrate coupling energy for metformin with amino acids F, W, H and Y, because of the interaction between the metformin dication and the electron cloud of π orbitals. The mutations analyzed showed changes in the chemical polarity and topology of the structure. The proposed diffusion model is a possible approach to the interaction mechanism between metformin and its transporter, as well as the impacts of variants, suggesting structural changes in the action of the drug. Metformin efficacy considerably varies from one patient to another; this may be largely attributed to the presence of mutations on the SLC22A1 gene. This study aims at proposing a potential structural model for metformin-hOCT1 (SLC22A1) transporter interaction, as well as the identification of the effect of mutations G401S (rs34130495), S189L (rs34104736), and R206C (616C > T) of the SLC22A1 gene at the topological and electronic structure levels on the channel surfaces, from a chemical viewpoint. Our results demonstrated that the coupling energies for metformin with aromatic amino acids F, W, H and Y, because of the interaction between the metformin dication and the electron cloud of π orbitals. Changes in the chemical environment's polarity and the structure's topology were reported in the mutations assessed. The diffusion model proposed is a potential approach for the mechanism of interaction of metformin with its transporter and the effects of variants on the efficacy of the drug in the treatment of type 2 diabetes. The assessment of the frequency of these mutations in a sample of Colombian type 2 diabetes patients suggests that different SLC22A1 gene variants might be involved in reduced OCT1 activity in the Colombian population since none of these mutations were detected.
PMID:33658930 | PMC:PMC7917475 | DOI:10.3389/fphar.2020.587590
The analysis of GSTA1 promoter genetic and functional diversity of human populations
Sci Rep. 2021 Mar 3;11(1):5038. doi: 10.1038/s41598-021-83996-2.
ABSTRACT
GSTA1 encodes a member of a family of enzymes that function to add glutathione to target electrophilic compounds, including carcinogens, therapeutic drugs, environmental toxins, and products of oxidative stress. GSTA1 has several functional SNPs within its promoter region that are responsible for a change in its expression by altering promoter function. This study aims to investigate distributions of GSTA1 promoter haplotypes across different human populations and to assess their impact on the expression of GSTA1. PHASE 2.1.1 was used to infer haplotypes and diplotypes of six GSTA1 promoter SNPs on 2501 individuals from 26 populations classified by the 1000 Genomes Project into five super-populations that included Africa (N = 660), America (N = 347), East Asia (N = 504), Europe (N = 502), and South Asia (N = 488). We used pairwise FST analysis to compare sub-populations and luciferase reporter assay (LRA) to evaluate the impact of each SNP on activation of transcription and interaction with other SNPs. The distributions of GSTA1 promoter haplotypes and diplotypes were significantly different among the different human populations. Three new promoter haplotypes were found in the African super-population. LRA demonstrated that SNPs at -52 and -69 has the most impact on GSTA1 expression, however other SNPs have a significant impact on transcriptional activity. Based on LRA, a new model of cis-elements interaction is presented. Due to the significant differences in GSTA1 diplotype population frequencies, future pharmacogenomics or disease-related studies would benefit from the inclusion of the complete GSTA1 promoter haplotype based on the newly proposed metabolic grouping derived from the LRA results.
PMID:33658540 | DOI:10.1038/s41598-021-83996-2
RNA tape sampling in cutaneous lupus erythematosus discriminates affected from unaffected and healthy volunteer skin
Lupus Sci Med. 2021 Mar;8(1):e000428. doi: 10.1136/lupus-2020-000428.
ABSTRACT
OBJECTIVE: Punch biopsy, a standard diagnostic procedure for patients with cutaneous lupus erythematosus (CLE) carries an infection risk, is invasive, uncomfortable and potentially scarring, and impedes patient recruitment in clinical trials. Non-invasive tape sampling is an alternative that could enable serial evaluation of specific lesions. This cross-sectional pilot research study evaluated the use of a non-invasive adhesive tape device to collect messenger RNA (mRNA) from the skin surface of participants with CLE and healthy volunteers (HVs) and investigated its feasibility to detect biologically meaningful differences between samples collected from participants with CLE and samples from HVs.
METHODS: Affected and unaffected skin tape samples and simultaneous punch biopsies were collected from 10 participants with CLE. Unaffected skin tape and punch biopsies were collected from 10 HVs. Paired samples were tested using quantitative PCR for a candidate immune gene panel and semi-quantitative immunohistochemistry for hallmark CLE proteins.
RESULTS: mRNA collected using the tape device was of sufficient quality for amplification of 94 candidate immune genes. Among these, we found an interferon (IFN)-dominant gene cluster that differentiated CLE-affected from HV (23-fold change; p<0.001) and CLE-unaffected skin (sevenfold change; p=0.002), respectively. We found a CLE-associated gene cluster that differentiated CLE-affected from HV (fourfold change; p=0.005) and CLE-unaffected skin (fourfold change; p=0.012), respectively. Spearman's correlation between per cent area myxovirus 1 protein immunoreactivity and IFN-dominant mRNA gene cluster expression was highly significant (dermis, rho=0.86, p<0.001). In total, skin tape-derived RNA expression comprising both IFN-dominant and CLE-associated gene clusters correlated with per cent area immunoreactivity of some hallmark CLE-associated proteins in punch biopsies from the same lesions.
CONCLUSIONS: A non-invasive tape RNA collection technique is a potential tool for repeated skin biomarker measures throughout a clinical trial.
PMID:33658303 | DOI:10.1136/lupus-2020-000428