Methamphetamine-induced changes in myocardial gene transcription are sex-dependent.

BACKGROUND: Prior work demonstrated that female rats (but not their male littermates) exposed to methamphetamine become hypersensitive to myocardial ischemic injury. Importantly, this sex-dependent effect persists following 30 days of subsequent abstinence from the drug, suggesting that it may be mediated by long term changes in gene expression that are not rapidly reversed following discontinuation of methamphetamine use. The goal of the present study was to determine whether methamphetamine induces sex-dependent changes in myocardial gene expression and whether these changes persist following subsequent abstinence from methamphetamine. RESULTS: Methamphetamine induced changes in the myocardial transcriptome were significantly greater in female hearts than male hearts both in terms of the number of genes affected and the magnitude of the changes. The largest changes in female hearts involved genes that regulate the circadian clock (Dbp, Per3, Per2, BMal1, and Npas2) which are known to impact myocardial ischemic injury. These genes were unaffected by methamphetamine in male hearts. All changes in gene expression identified at day 11 returned to baseline by day 30. CONCLUSIONS: These data demonstrate that female rats are more sensitive than males to methamphetamine-induced changes in the myocardial transcriptome and that methamphetamine does not induce changes in myocardial transcription that persist long term after exposure to the drug has been discontinued.

The impact of tacrolimus exposure on extrarenal adverse effects in adult renal transplant recipients.

AIMS: Tacrolimus has been associated with notable extrarenal adverse effects (AEs), which are unpredictable and impact patient morbidity. The association between model-predicted tacrolimus exposure metrics and standardized extrarenal AEs in stable renal transplant recipients was investigated and a limited sampling strategy (LSS) was developed to predict steady-state tacrolimus area under the curve over a 12-h dosing period (AUCss,0-12h ). METHODS: All recipients receiving tacrolimus and mycophenolic acid ≥6 months completed a 12-h cross-sectional observational pharmacokinetic-pharmacodynamic study. Patients were evaluated for the presence of individual and composite gastrointestinal, neurological, and aesthetic AEs during the study visit. The associations between AEs and tacrolimus exposure metrics generated from a published population pharmacokinetic model were investigated using a logistic regression analysis in NONMEM 7.3. An LSS was determined using a Bayesian estimation method with the same patients. RESULTS: Dose-normalized tacrolimus AUCss,0-12h and apparent clearance were independently associated with diarrhoea, dyspepsia, insomnia and neurological AE ratio. Dose-normalized tacrolimus maximum concentration was significantly correlated with skin changes and acne. No AE associations were found with trough concentrations. Using limited sampling at 0, 2h; 0, 1, 4h; and 0, 1, 2, 4h provided a precise and unbiased prediction of tacrolimus AUC (root mean squared prediction error < 10%), which was not well characterized using trough concentrations only (root mean squared prediction error >15%). CONCLUSIONS: Several AEs (i.e. diarrhoea, dyspepsia, insomnia and neurological AE ratio) were associated with tacrolimus dose normalized AUCss,0-12h and clearance. Skin changes and acne were associated with dose-normalized maximum concentrations. To facilitate clinical implementation, a LSS was developed to predict AUCss,0-12h values using sparse patient data to efficiently assess projected immunosuppressive exposure and potentially minimize AE manifestations.

Sequential Evolution of Vancomycin-Intermediate Resistance Alters Virulence in Staphylococcus aureus: Pharmacokinetic/Pharmacodynamic Targets for Vancomycin Exposure.

Staphylococcus aureus possesses exceptional virulence and a remarkable ability to adapt in the face of antibiotic therapy. We examined the in vitro evolution of S. aureus in response to escalating vancomycin exposure by evaluating bacterial killing and the progression of resistance. A hollow-fiber infection model was utilized to simulate human doses of vancomycin increasing from 0.5 to 4 g every 12 h (q12h) versus a high inoculum (10(8) CFU/ml) of methicillin-resistant S. aureus (MRSA) USA300 and USA400. Host-pathogen interactions using Galleria mellonella and accessory gene regulator (agr) expression were studied in serially obtained isolates. In both USA300 and USA400 MRSA isolates, vancomycin exposure up to 2 g q12h resulted in persistence and regrowth, whereas 4 g administered q12h achieved sustained killing against both strains. As vancomycin exposure increased from 0.5 to 2 g q12h, the bacterial population shifted toward vancomycin-intermediate resistance, and collateral increases in the MICs of daptomycin and televancin were observed over 10 days. Guideline-recommended exposure of a ratio of the area under the concentration-time curve for the free, unbound fraction of the drug to the MIC (fAUC/MIC ratio) of 200 displayed a 0.344-log bacterial reduction in area, whereas fAUC/MICs of 371 and 554 were needed to achieve 1.00- and 2.00-log reductions in area, respectively. The stepwise increase in resistance paralleled a decrease in G. mellonella mortality (P = 0.021) and a gradual decline of RNAIII expression over 10 days. Currently recommended doses of vancomycin resulted in amplification of resistance and collateral damage to other antibiotics. Decreases in agr expression and virulence during therapy may be an adaptive mechanism of S. aureus persistence.

Trends in the Number of Authors and Institutions in Papers Published in AJPE 2015-2019.

Objective. To investigate the number of authors and unique institutions per paper published in the American Journal of Pharmaceutical Education (AJPE) in 2015 through 2019, and to examine the number of authors and unique institutions for papers that were nominated for the Rufus A. Lyman Award in the same period.Methods. Articles published in AJPE from 2015 through 2019 were reviewed. Data collected for each article included article type, number of authors, and number of institutions.Results. Of the 811 articles published in AJPE during this period, the number of authors increased significantly from a mean (SD) of 3.5 (1.8) to 4.5 (2.2). The number of unique institutions also increased significantly from 1.7 (1.1) to 2.4 (1.8).Conclusion. There is a trend toward a greater number of authors and unique institutions for the publications in one pharmacy education journal. Explanations for this trend may include pressure to publish, increased research complexity, and expanded interprofessional collaboration.

Comparison of P-glycoprotein function in peripheral blood mononuclear cells ex vivo in stable Black and White male and female kidney transplant recipients.

Kidney allograft survival remains poorer in Black compared to White recipients due to racial differences in calcineurin inhibitor (CNI) pharmacology. P-glycoprotein (P-gp), an ABC efflux transporter expressed in peripheral blood mononuclear cells (PBMCs), modulates CNI pharmacokinetics and intracellular pharmacology. This study investigated P-gp function in PBMC ex vivo at 0 (trough), 4, 8, and 12 h in stable Black and White male and female kidney transplant recipients (n = 67) receiving tacrolimus and mycophenolic acid. Tacrolimus doses were adjusted to troughs of 4-10 ng/ml. P-gp function was quantified with flow cytometric measurement of cyclosporine (CYA; 2.5 µM)-reversible efflux of P-gp substrate, 3,3'-Diethyloxacarbocyanine iodide by determining the percentage change of mean fluorescent intensity (MFI) with CYA (% ΔMFI). The composite parameter of area under the concentration versus time (AUC)0-12h % ΔMFI estimated P-gp function. Data analysis examined race, sex, and race-sex associations to P-gp function. A secondary aim analyzed ABCB1 genotypes: 1236C>T (rs1128503), 2677G>T/A (rs2032582), 3435C>T (rs1045642), and P-gp function. P-gp function (% ΔMFI) was higher in White patients at troughs (p = 0.031) compared to Black counterparts with similar trends at 4 and 8 h. Reduced AUC0-12h % ΔMFI was noted in Black recipients (N = 32) compared with Whites (N = 35, p = 0.029) with notable pairwise adjusted differences between Black and White women (p = 0.021). Higher AUC0-12h % ΔMFI was associated with ABCB1 2677 TT compared to GG variants (p = 0.035). The AUC0-12h % ΔMFI was greater in White than Black subjects. P-gp function was higher at troughs in White subjects and differed between race-sex groups. P-gp function in PBMC may influence intracellular tacrolimus exposure and inter-relating pharmacodynamic responses which may support race and sex pharmacologic differences.

Front-loaded linezolid regimens result in increased killing and suppression of the accessory gene regulator system of Staphylococcus aureus.

Front loading is a strategy used to optimize the pharmacodynamic profile of an antibiotic through the administration of high doses early in therapy for a short duration. Our aims were to evaluate the impact of front loading of linezolid regimens on bacterial killing and suppression of resistance and on RNAIII, the effector molecule of the accessory gene regulator system (encoded by agr) in methicillin-resistant Staphylococcus aureus (MRSA). Time-killing experiments over 48 h were utilized for linezolid against four strains of MRSA: USA100, USA300, USA400, and ATCC 29213. A hollow-fiber infection model simulated traditional and front-loaded human therapeutic regimens of linezolid versus USA300 at 10(6) CFU/ml over 240 h. Over 48 h in time-kill experiments, linezolid displayed bacteriostatic activity, with reductions of >1 log(10) CFU/ml for all strains. Front-loaded regimens that were administered over 5 days, 1,200 mg every 12 h (q12h) (total, 10 doses) and 2,400 mg q12h (total, 10 doses) followed by 300 mg q12h thereafter, resulted in sustained bactericidal activity, with reductions of the area under the CFU curve of -6.15 and -6.03, respectively, reaching undetectable limits at the 10-day study endpoint. All regimens displayed a reduction in RNAIII relative expression at 24 h and 240 h compared with that of the growth control. Monte Carlo simulations predicted a <1.27× increase in the fractional decreases in platelets for all front-loaded regimens versus the 600 mg q12h regimen, except for the highest-dose front-loaded regimen. Front-loading strategies for linezolid are promising and may be of utility in severe MRSA infections, where early aggressive therapy is necessary.

Prenatal Exposure to Methamphetamine Causes Vascular Dysfunction in Adult Male Rat Offspring.

Methamphetamine use during pregnancy can have negative consequences on the offspring. However, most studies investigating the impact of prenatal exposure to methamphetamine have focused on behavioral and neurological outcomes. Relatively little is known regarding the impact of prenatal methamphetamine on the adult cardiovascular system. This study investigated the impact of chronic fetal exposure to methamphetamine on vascular function in adult offspring. Pregnant female rats received daily saline or methamphetamine (5 mg/kg) injections starting on gestational day 1 and continuing until the pups were born. Vascular function was assessed in 5 month old offspring. Prenatal methamphetamine significantly decreased both the efficacy and potency of acetylcholine-induced relaxation in isolated male (but not female) aortas when perivascular adipose tissue (PVAT) remained intact. However, prenatal methamphetamine had no impact on acetylcholine-induced relaxation when PVAT was removed. Nitroprusside-induced relaxation of the aorta was unaffected by prenatal methamphetamine. Angiotensin II-induced contractile responses were significantly potentiated in male (but not female) aortas regardless of the presence of PVAT. This effect was reversed by L-nitro arginine methyl ester (L-NAME). Serotonin- and phenylephrine-induced contraction were unaffected by prenatal methamphetamine. Prenatal methamphetamine had no impact on acetylcholine-induced relaxation of third order mesenteric arteries and no effect on basal blood pressure. These data provide evidence that prenatal exposure to methamphetamine sex-dependently alters vasomotor function in the vasculature and may increase the risk of developing vascular disorders later in adult life.

Maternal use of methamphetamine induces sex-dependent changes in myocardial gene expression in adult offspring.

Methamphetamine is a commonly abused illicit stimulant that has prevalent use among women of child-bearing age. While there are extensive studies on the neurological effects of prenatal methamphetamine exposure, relatively little is known about the effect of prenatal methamphetamine on the adult cardiovascular system. Earlier work demonstrated that prenatal methamphetamine exposure sex dependently (females only) sensitizes the adult heart to ischemic injury. These data suggest that prenatal exposure to methamphetamine may induce sex-dependent changes in cardiac gene expression that persist in adult offspring. The goal of this study was to test the hypothesis that prenatal methamphetamine exposure induces changes in cardiac gene expression that persist in the adult heart. Hearts of prenatally exposed female offspring exhibited a greater number of changes in gene expression compared to male offspring (184 changes compared with 74 in male offspring and 89 changes common between both sexes). Dimethylarginine dimethylaminohydrolase 2 and 3-hydroxybutyrate dehydrogenase 1 (genes implicated in heart failure) were shown by Western Blot to be under expressed in adult females that were prenatally exposed to methamphetamine, while males were deficient in 3-Hydroxybutyrate Dehydrogenase 1 only. These data indicate that prenatal methamphetamine exposure induces changes in gene expression that persist into adulthood. This is consistent with previous findings that prenatal methamphetamine sex dependently sensitizes the adult heart to ischemic injury and may increase the risk of developing cardiac disorders during adulthood.

Race and sex associations with tacrolimus pharmacokinetics in stable kidney transplant recipients.

STUDY OBJECTIVE: This study investigated race and sex differences in tacrolimus pharmacokinetics and pharmacodynamics in stable kidney transplant recipients. DESIGN AND SETTING: A cross-sectional, open-label, single center, 12-h pharmacokinetic-pharmacodynamic study was conducted. Tacrolimus pharmacokinetic parameters included area under the concentration-time curve (AUC0-12 ), AUC0-4 , 12-h troughs (C12 h ), maximum concentrations (Cmax ), oral clearance (Cl), with dose-normalized AUC0-12 , troughs, and Cmax with standardized adverse effect scores. Statistical models were used to analyze end points with individual covariate-adjustment including clinical factors, genotypic variants CYP3A5*3, CYP3A5*6, CYP3A5*7(CYP3A5*3*6*7) metabolic composite, and ATP binding cassette gene subfamily B member 1 (ABCB1) polymorphisms. PATIENTS: 65 stable, female and male, Black and White kidney transplant recipients receiving tacrolimus and mycophenolic acid ≥6 months post-transplant were evaluated. MEASUREMENTS AND MAIN RESULTS: Black recipients exhibited higher tacrolimus AUC0-12 (Race: p = 0.005), lower AUC* (Race: p < 0.001; Race × Sex: p = 0.068), and higher Cl (Race: p < 0.001; Sex: p = 0.066). Greater cumulative (Sex: p < 0.001; Race × Sex: p = 0.014), neurologic (Sex: p = 0.021; Race × Sex: p = 0.005), and aesthetic (Sex: p = 0.002) adverse effects were found in females, with highest scores in Black women. In 84.8% of Black and 68.8% of White patients, the target AUC0-12 was achieved (p = 0.027). In 31.3% of White and 9.1% of Black recipients, AUC0-12 was <100 ng‧h/ml despite tacrolimus troughs in the target range (p = 0.027). The novel CYP3A5*3*6*7 metabolic composite was the significant covariate accounting for 15%-19% of tacrolimus variability in dose (p = 0.002); AUC0-12 h * (p < 0.001), and Cl (p < 0.001). CONCLUSIONS: Tacrolimus pharmacokinetics and adverse effects were different among stable kidney transplant recipient groups based upon race and sex with interpatient variability associated with the CYP3A5*3*6*7 metabolic composite. More cumulative, neurologic, and aesthetic adverse effects were noted among females. Tacrolimus regimens that consider race and sex may reduce adverse effects and enhance allograft outcomes by facilitating more patients to achieve the targeted AUC0-12 h .

Nitroglycerin alters matrix remodeling proteins in THP-1 human macrophages and plasma metalloproteinase activity in rats.

Several studies suggested that long-term nitrate therapy may produce negative outcomes in patient mortality and morbidity. A possible mechanism may involve nitrate-mediated activation of various extracellular matrix (ECM) proteases, particularly matrix metalloproteinase-9 (MMP-9), and adhesion molecules in human macrophages, leading to the destabilization of atherosclerotic plaques. We examined the gene and protein regulating effects on THP-1 human macrophages by repeated exposure to therapeutically relevant concentrations of nitroglycerin (NTG) and possible involvement of nuclear factor (NF)-κB signaling mechanism in mediating some of these observed effects. THP-1 human macrophages repeatedly exposed to NTG (at 10 nM, added on days 1, 4 and 7) exhibited extensive alterations in the expression of multiple genes encoding ECM proteases and adhesion molecules. These effects were dissimilar to those produced by a direct nitric oxide donor, diethylenetriamine NONOate. NTG exposure significantly up-regulated NF-κB DNA nuclear binding activity and MMP-9 protein expression, and reduced tissue inhibitor of metalloproteinase-1 (TIMP-1) expression; these effects were abrogated in the presence of the NF-κB inhibitor parthenolide (a chemical inhibitor derived from the feverfew plant). Further, we examined whether our in vitro findings (an elevated MMP-9/TIMP-1 ratio and gelatinase activity) can be translated to in vivo effects, in a rat model. Sprague-Dawley rats exposed continuously to NTG subcutaneously for 8 days via mini-osmotic pumps showed significant induction of plasma MMP-9 dimer concentrations and the expression of a complex of MMP-9 with lipocalin-2 or neutrophil gelatinase associated lipocalin (NGAL). Plasma gelatinase activity was significantly increased by NTG over the entire study period, attaining peak elevation at day 6. Plasma TIMP-1 protein was down-regulated significantly by day 2 and days 4-7 in the NTG-treated rats. Pharmacokinetic monitoring of NTG and its dinitrate metabolites indicated that concentrations were well within therapeutic levels observed in humans. Our studies indicate that clinically relevant concentrations of NTG not only altered ECM matrix by changing the expression of multiple genes that govern cellular integrity, affecting cellular MMP-9/TIMP-1 balance in THP-1 human macrophages possibly via NF-κB activation, but also led to systemic changes in MMP-9/TIMP-1 expression and gelatinase activity in rats. These effects may contribute to extracellular matrix degradation and possible atherosclerotic plaque destabilization.

Dietary phenethyl isothiocyanate alters gene expression in human breast cancer cells.

Phenethyl isothiocyanate (PEITC), a component in cruciferous vegetables, can block chemical carcinogenesis in animal models. Our objective was to determine the effect of treatment with PEITC on gene expression changes in MCF-7 human breast cancer cells in order to evaluate potential mechanisms involved in its chemopreventive effects. MCF-7 cells were treated for 48 hours with either PEITC (3 µM) or the vehicle. Total RNA was extracted from cell membrane preparations, and labeled cDNA's representing the mRNA pool were reverse-transcribed directly from total RNA isolated for use in the microarray hybridizations. Two specific human GE Array Kits (Superarray Inc.) that both contain 23 marker genes, related to signal transduction pathways or cancer/tumor suppression, plus 2 housekeeping genes (ß-actin and GAPDH), were utilized. Arrays from treated and control cells (n = 4 per group) were evaluated using a Student's t-test. Gene expression was significantly induced for tumor protein p53 (p53), cyclin-dependent kinase inhibitor 1C (p57 Kip2), breast cancer Type 2 early onset (BRCA2), cAMP responsive element binding protein 2 (ATF-2), interleukin 2 (IL-2), heat shock 27 KD protein (hsp27), and CYP19 (aromatase). Induction of p57 Kip2, p53, BRCA2, IL-2, and ATF-2 would be expected to decrease cellular proliferation and increase tumor suppression and/or apoptosis. PEITC treatment produced significant alterations in some genes involved in tumor suppression and cellular proliferation/apoptosis that may be important in explaining the chemopreventive effects of PEITC.

Perspectives on natural compounds in chemoprevention and treatment of cancer: an update with new promising compounds.

Cancer is the second deadliest disease worldwide. Although recent advances applying precision treatments with targeted (molecular and immune) agents are promising, the histological and molecular heterogeneity of cancer cells and huge mutational burdens (intrinsic or acquired after therapy) leading to drug resistance and treatment failure are posing continuous challenges. These recent advances do not negate the need for alternative approaches such as chemoprevention, the pharmacological approach to reverse, suppress or prevent the initial phases of carcinogenesis or the progression of premalignant cells to invasive disease by using non-toxic agents. Although data are limited, the success of several clinical trials in preventing cancer in high-risk populations suggests that chemoprevention is a rational, appealing and viable strategy to prevent carcinogenesis. Particularly among higher-risk groups, the use of safe, non-toxic agents is the utmost consideration because these individuals have not yet developed invasive disease. Natural dietary compounds present in fruits, vegetables and spices are especially attractive for chemoprevention and treatment because of their easy availability, high margin of safety, relatively low cost and widespread human consumption. Hundreds of such compounds have been widely investigated for chemoprevention and treatment in the last few decades. Previously, we reviewed the most widely studied natural compounds and their molecular mechanisms, which were highly exploited by the cancer research community. In the time since our initial review, many promising new compounds have been identified. In this review, we critically review these promising new natural compounds, their molecular targets and mechanisms of anticancer activity that may create novel opportunities for further design and conduct of preclinical and clinical studies.

Perspectives for synthetic curcumins in chemoprevention and treatment of cancer: An update with promising analogues.

Curcumin, a pure compound extracted from the flowering plant, turmeric (Curcuma longa. Zingiberaceae), is a common dietary ingredient found in curry powder. It has been studied extensively for its anti-inflammatory, antioxidant, antimicrobial and anti-tumour activities. Evidence is accumulating demonstrating its potential in chemoprevention and as an anti-tumour agent for the treatment of cancer. Despite demonstrated safety and tolerability, the clinical application of curcumin is frustrated by its poor solubility, metabolic instability and low oral bioavailability. Consequently researchers have tried novel techniques of formulation and delivery as well as synthesis of analogues with enhanced properties to overcome these barriers. This review presents the synthetic analogues of curcumin that have proven their anticancer potential from different studies. It also highlights studies that combined these analogues with approved chemotherapies and delivered them via novel techniques. Currently, there are no reports of clinical studies on any of the synthetic congeners of curcumin and this presents an opportunity for future research. This review presents the synthetic analogues of curcumin and makes a compelling argument for their potential application in the management of cancerous disease.

Association of ABCC2 Haplotypes to Mycophenolic Acid Pharmacokinetics in Stable Kidney Transplant Recipients.

Mycophenolic acid exhibits significant interpatient pharmacokinetic variability attributed to factors including race, sex, concurrent medications, and enterohepatic circulation of the mycophenolic acid glucuronide metabolite to mycophenolic acid. This conversion by enterohepatic circulation is mediated by the multidrug resistance-associated protein 2, encoded by ABCC2. This study investigated ABCC2 haplotype associations with mycophenolic acid pharmacokinetics in 147 stable kidney transplant recipients receiving mycophenolic acid in combination with calcineurin inhibitors. The role of the ABCC2 genotypes -24C>T (rs717620), 1249C>T (rs2273697), and 3972C>T (rs3740066) were evaluated in prospective, cross-sectional pharmacokinetic studies of stable recipients receiving mycophenolic acid and either tacrolimus or cyclosporine. Haplotype phenotypic associations with mycophenolic acid pharmacokinetic parameters were computed using THESIAS (v. 3.1). Four ABCC2 haplotypes with estimated frequencies greater than 10% were identified (H1:CGC [wild type], H9:CGT, H2:CAC, H12:TGT). There were no differences in haplotype frequencies by either race or sex. There were significant associations of pharmacokinetic parameters with ABCC2 haplotypes for mycophenolic acid clearance (L/h), mycophenolic acid AUC0-12h (mg·h/L), and the ratio of mycophenolic acid glucuronide to mycophenolic acid AUC0-12h . The wild-type haplotype ABCC2 CGC had greater mycophenolic acid AUC0-12h (P = .017), slower clearance (P = .013), and lower mycophenolic acid glucuronide to mycophenolic acid AUC0-12h ratio (P = .047) compared with the reduced function ABCC2 haplotype CGT. These differences were most pronounced among patients receiving tacrolimus cotreatment. No phenotypic associations were found with the cyclosporine-mycophenolic acid regimen. Variation in ABCC2 haplotypes contributes to subtherapeutic mycophenolic acid exposure and influences interpatient variability in pharmacokinetic phenotypes based on concurrent calcineurin inhibitor treatment.

Broad regulation of matrix and adhesion molecules in THP-1 human macrophages by nitroglycerin.

Although nitroglycerin (NTG) is effective for the acute relief in coronary ischemic diseases, its long-term benefits in mortality and morbidity have been questioned. The possibility has been raised that NTG may increase the activity of matrix metalloproteinases (MMP), which could lead to disruption and dislodging of atherosclerotic plaques. This study examined the broad effects of acute NTG exposure on the expression and activity of genes encoding MMP-9, as well as an array of ECM and adhesion molecules in THP-1 human macrophages. Gene array studies identified that while NTG exposure (100microM, 48h) did not significantly increase MMP-9 gene expression, genes encoding testican-1, integrin alpha-1, thrombospondin-3, fibronectin-1 and MMP-26 were significantly down-regulated. On the other hand, genes encoding catenin beta-1 and vascular cell-adhesion molecule-1 were up-regulated. Real-time PCR studies confirmed significant down-regulation of testican-1 gene expression, but its protein expression was not significantly altered. NTG exposure, caused a significant increase in total MMP-9 protein expression (1.96-fold) and active MMP-9 (3.7-fold) concentrations. Recombinant MMP-9 was significantly activated by NTG and its dinitrate metabolites, indicating post-translation modification of this protein by organic nitrates. These results indicate that NTG exposure could broadly affect the gene expression and activity of proteases that govern the ECM cascade, thereby potentially altering atherosclerotic plaque stability.

Beyond Single Nucleotide Polymorphisms: CYP3A5∗3∗6∗7 Composite and ABCB1 Haplotype Associations to Tacrolimus Pharmacokinetics in Black and White Renal Transplant Recipients.

Interpatient variability in tacrolimus pharmacokinetics is attributed to metabolism by cytochrome P-450 3A5 (CYP3A5) isoenzymes and membrane transport by P-glycoprotein. Interpatient pharmacokinetic variability has been associated with genotypic variants for both CYP3A5 or ABCB1. Tacrolimus pharmacokinetics was investigated in 65 stable Black and Caucasian post-renal transplant patients by assessing the effects of multiple alleles in both CYP3A5 and ABCB1. A metabolic composite based upon the CYP3A5 polymorphisms: ∗3(rs776746), ∗6(10264272), and ∗7(41303343), each independently responsible for loss of protein expression was used to classify patients as extensive, intermediate and poor metabolizers. In addition, the role of ABCB1 on tacrolimus pharmacokinetics was assessed using haplotype analysis encompassing the single nucleotide polymorphisms: 1236C > T (rs1128503), 2677G > T/A(rs2032582), and 3435C > T(rs1045642). Finally, a combined analysis using both CYP3A5 and ABCB1 polymorphisms was developed to assess their inter-related influence on tacrolimus pharmacokinetics. Extensive metabolizers identified as homozygous wild type at all three CYP3A5 loci were found in 7 Blacks and required twice the tacrolimus dose (5.6 ± 1.6 mg) compared to Poor metabolizers [2.5 ± 1.1 mg (P < 0.001)]; who were primarily Whites. These extensive metabolizers had 2-fold faster clearance (P < 0.001) with 50% lower AUC∗ (P < 0.001) than Poor metabolizers. No differences in C12 h were found due to therapeutic drug monitoring. The majority of blacks (81%) were classified as either Extensive or Intermediate Metabolizers requiring higher tacrolimus doses to accommodate the more rapid clearance. Blacks who were homozygous for one or more loss of function SNPS were associated with lower tacrolimus doses and slower clearance. These values are comparable to Whites, 82% of who were in the Poor metabolic composite group. The ABCB1 haplotype analysis detected significant associations of the wildtype 1236T-2677T-3435T haplotype to tacrolimus dose (P = 0.03), CL (P = 0.023), CL/LBW (P = 0.022), and AUC∗ (P = 0.078). Finally, analysis combining CYP3A5 and ABCB1 genotypes indicated that the presence of the ABCB1 3435 T allele significantly reduced tacrolimus clearance for all three CPY3A5 metabolic composite groups. Genotypic associations of tacrolimus pharmacokinetics can be improved by using the novel composite CYP3A5∗3∗4∗5 and ABCB1 haplotypes. Consideration of multiple alleles using CYP3A5 metabolic composites and drug transporter ABCB1 haplotypes provides a more comprehensive appraisal of genetic factors contributing to interpatient variability in tacrolimus pharmacokinetics among Whites and Blacks.

AMBIENCE: a novel approach and efficient algorithm for identifying informative genetic and environmental associations with complex phenotypes.

We developed a computationally efficient algorithm AMBIENCE, for identifying the informative variables involved in gene-gene (GGI) and gene-environment interactions (GEI) that are associated with disease phenotypes. The AMBIENCE algorithm uses a novel information theoretic metric called phenotype-associated information (PAI) to search for combinations of genetic variants and environmental variables associated with the disease phenotype. The PAI-based AMBIENCE algorithm effectively and efficiently detected GEI in simulated data sets of varying size and complexity, including the 10K simulated rheumatoid arthritis data set from Genetic Analysis Workshop 15. The method was also successfully used to detect GGI in a Crohn's disease data set. The performance of the AMBIENCE algorithm was compared to the multifactor dimensionality reduction (MDR), generalized MDR (GMDR), and pedigree disequilibrium test (PDT) methods. Furthermore, we assessed the computational speed of AMBIENCE for detecting GGI and GEI for data sets varying in size from 100 to 10(5) variables. Our results demonstrate that the AMBIENCE information theoretic algorithm is useful for analyzing a diverse range of epidemiologic data sets containing evidence for GGI and GEI.

Comparison of the effects of phenethyl isothiocyanate and sulforaphane on gene expression in breast cancer and normal mammary epithelial cells.

Phenethyl isothiocyanate (PEITC) and sulforaphane (SF) exhibit tumor preventive activity in lung, prostate, breast and colon cancers. Our objective was to examine the effect of these two isothiocyanates on estrogen receptor-related genes, and genes related to apoptosis and cell cycle in the estrogen-dependent breast cancer cell line MCF7 and in normal human epithelial breast (HME) cells. We treated cells with 0.3 microM or 3.0 microM concentrations of PEITC or SF. In HME cells, gene expression was significantly altered for 23 genes by PEITC at a concentration of 0.3 microM and 4 genes at 3.0 microM. SF altered the expression of 16 genes at a concentration of 0.3 microM and 2 genes at 3.0 microM. In HME cells, genes altered by both PEITC and SF exhibited changes in gene expression that were similar in extent as well as direction of change. In MCF-7 cells, PEITC did not produce any significant changes in the gene expression at both treatment levels. SF produced significant changes in 7 genes, but only at the higher treatment level of 3.0 microM. Normal mammary cells exhibited more changes in the expression of estrogen receptor related genes than did breast cancer cells, and significantly these changes occurred predominantly at the low concentration of 0.3 microM, a concentration achievable by dietary input of isothiocyanates. Novel findings were the upregulation of the pro-apoptotic gene BAD and estrogen receptor beta gene in normal human mammary cells. These gene alterations observed, along with upregulation of tumor suppressors p21 and p27, may provide a protective effect to mammary cells against breast cancer.

Influence of Exercise Time of Day on Salivary Melatonin Responses.

BACKGROUND: Sleep deprivation negatively affects cognition, pain, mood, metabolism, and immunity, which can reduce athletic performance. Melatonin facilitates sleepiness and may be affected by the proximity of exercise to sleep. PURPOSE: To evaluate the influence of exercise time of day on salivary melatonin (s-melatonin) responses. METHODS: Twelve regularly exercising men (age 20.75 [0.62] y, height 1.75 [0.04] m, mass 73.63 [10.43] kg, and maximal oxygen consumption 57.72 [6.11] mL/kg/min) participated in a randomized, crossover design. Subjects completed 3 protocols-morning exercise (09:00 h), afternoon exercise (16:00 h), and no exercise (CON)-at least 5 d apart. Exercise sessions consisted of 30 min of steady-state running at 75% of maximal oxygen consumption. Saliva was collected via passive drool at 20:00, 22:00, and 03:00 h following all sessions. RESULTS: Repeated-measures analysis of variance revealed significant time (P = .001) and condition (P = .026) effects for melatonin. Levels of s-melatonin were significantly increased at 03:00 h compared with 20:00 and 22:00 h for all conditions. Post hoc analyses revealed that s-melatonin at 22:00 h was significantly higher after morning exercise (16.5 [7.5] pg/mL) compared with afternoon exercise (13.7 [6.1] pg/mL) sessions (P = .03), whereas neither exercise condition significantly differed from the control (P > .05). CONCLUSIONS: It appears that exercising in the afternoon may blunt melatonin secretion compared with morning exercise. If sleep is an issue, morning exercise may be preferable to afternoon exercise.

Information-theoretic identification of predictive SNPs and supervised visualization of genome-wide association studies.

The size, dimensionality and the limited range of the data values makes visualization of single nucleotide polymorphism (SNP) datasets challenging. The purpose of this study is to evaluate the usefulness of 3D VizStruct, a novel multi-dimensional data visualization technique for SNP datasets capable of identifying informative SNPs in genome-wide association studies. VizStruct is an interactive visualization technique that reduces multi-dimensional data to three dimensions using a combination of the discrete Fourier transform and the Kullback-Leibler divergence. The performance of 3D VizStruct was challenged with several diverse, biologically relevant published datasets including the human lipoprotein lipase (LPL) gene locus, the human Y-chromosome in several populations and a multi-locus genotype dataset of coral samples from four populations. In every case, the SNPs and or polymorphic markers identified by the 3D VizStruct mapping were predictive of the underlying biology.