Effect of Obesity and Roux-En-Y Gastric Surgery on Omeprazole Pharmacokinetics.

INTRODUCTION: The prevalence of obesity is increasing globally. The principal aim was to evaluate whether gastric bypass surgery modifies the bioavailability and pharmacokinetic (PK) parameters of omeprazole. METHODS: Controlled, open-label, bioavailability clinical trial in patients undergoing Roux-en-Y gastric bypass (RYGB). Healthy patients with obesity (body mass index >35) were included and assessed for omeprazole PKs before and after RYGB (1 and 6 months). PK sampling was done at baseline and several times up to 12 h after drug dosing. Pre- and post-surgery parameters were compared using paired ANOVA or Wilcoxon tests, and control versus cases using ANOVA or Mann-Whitney tests. Given the post-surgery change in body weight, parameters were corrected by dose/body weight. RESULTS: Fourteen case and 24 control subjects were recruited; 92% were women (N = 35/38). In patients who underwent RYGB, maximum plasma concentration (Cmax) was significantly reduced at 1 and 6 months after surgery compared with presurgery values (p = 0.001). Regarding the AUC, the values are lower at 1 and 6 months after surgery than at baseline (p < 0.001). The drug clearance was also increased in the first month after surgery. No differences were found between patients 6 months after surgery and controls. Cmax and AUC corrected by dose/body weight were significantly different between the baseline surgery subjects and controls. Discusion/Conclusions: Omeprazole bioavailability is reduced in patients with obesity at 1 and 6 months after RYGB. However, omeprazole PK parameters 6 months after RYGB are similar to control subjects, and thus no dose correction is required after RYGB for a given indication.

Physical Performance and Quality of Life in Older Adults: Is There Any Association between Them and Potential Drug Interactions in Polymedicated Octogenarians.

Older adults are at increased risk of several cytochrome P450 (CYP) drug interactions that can result in drug toxicity, reduced pharmacological effect, and adverse drug reactions. This study aimed to assess the prevalence of potential CYP interactions referring to the most clinically relevant drugs and exploring the relationship between them and quality of life and physical performance in Spanish octogenarians. Institutionalized and community-dwelling octogenarians (n = 102) treated at three primary care centers, were recruited by a research nurse. Anthropometric measurements, chronic diseases, prescribed drugs, quality of life, physical performance, mobility skills, hand grip strength and cognitive status data were collected. Potential CYP drug-drug interactions (DDIs) were selected referring to the main CYP implicated in their metabolism. The 72.2% of recruited octogenarians presented potentially inappropriate CYP inhibitor-substrate or CYP inductor-substrate combinations. Analyzing the EuroQol Visual Analogue scale (EQ-VAS) results, patients with a potential CYP DDI perceived worse health status than patients without it (p = 0.004). In addition, patients with a potential CYP DDI presented worse exercise capacity, kinesthetic abilities, or mobility than those who didn't present a potential interaction (p = 0.01, p = 0.047, and p = 0.02, respectively). To investigate and control factors associated with loss of muscle strength and poor quality of life, polypharmacy and DDIs could help institutions in the management of physical frailty.

Association of HTR2A-1438G/A Genetic Polymorphism With Smoking and Chronic Obstructive Pulmonary Disease / Asociación del polimorfismo genético HTR2A-1438G/A con el tabaco y la enfermedad pulmonar obstructiva crónica

Introduction: Cigarette smoking is a major risk factor in the development of chronic obstructive pulmonary disease (COPD). Serotonin levels have been associated with COPD and smoking has been as a significant modulator. Elevated levels of serotonin are responsible for bronchoconstriction and pulmonary vasoconstriction and also nicotine dependence, thus serotonin response could be affected by genetic polymorphisms in transporters and receptors of serotonin. Objectives: The aim of the current study was to analyze the effect of SLC6A4 (5HTT_LPR) (rs25531) and HTR2A-1438G/A (rs6311) genetic polymorphisms on the relation between smoking habits and COPD. Methods: The association between SLC6A4 (5HTT_LPR) (rs25531), HTR2A-1438G/A (rs6311), smoking degree and COPD was analyzed in a total of 77 COPD patients (active smokers) and 90 control subjects (active healthy smokers). The DNA was extracted of peripheral leukocytes samples and genotyping was performed using an allele specific polymerase chain reaction. Results: The distribution of SLC6A4 genotypes did not vary between healthy smokers and COPD patients (P = 0.758). On the other hand, the A allele of HTR2A (rs6311) was significantly associated with COPD incidence in the trend model (P = 0.02; 1.80 [1.04-3.11]). Among all smokers, this allele was also associated with the number of pack years smoked (P = 0.02) and also, we observed a marginal association with FEV1/FVC values (P = 0.06). Conclusion: Our results point a possible role of the A allele of HTR2A (rs6311) in COPD pathogenesis, suggesting that this effect depends partly on tobacco consumption due to a gene-by-environment interaction

Introducción: El consumo de tabaco es el principal riesgo para desarrollar enfermedad pulmonar obstructiva crónica (EPOC). Los niveles de serotonina se han relacionado con el riesgo de desarrollo de EPOC, siendo el consumo de tabaco un modulador significativo. Los niveles elevados de serotonina producen broncoconstricción y vasoconstricción pulmonar, así como dependencia a la nicotina. Así, la respuesta a serotonina podría verse afectada por los polimorfismos genéticos en los transportadores y receptores de este neurotransmisor. Objetivos: El objetivo de este estudio fue analizar el papel de los polimorfismos genéticos SLC6A4 (5HTT_LPR) (rs25531) y HTR2A -1438G/A (rs6311) en la relación entre el consumo de tabaco y la EPOC. Métodos: Se analizó la asociación entre SLC6A4 (5HTT_LPR) (rs25531), HTR2A -1438G/A (rs6311), grado de tabaquismo y EPOC en 77 pacientes con EPOC (fumadores activos) y 90 sujetos control (fumadores activos sanos). El ADN se extrajo a partir de leucocitos de sangre periférica y la genotipificación se realizó utilizando la reacción en cadena de la polimerasa alelo-específica. Resultados: No se observaron diferencias en la distribución de genotipos SLC6A4 entre fumadores sanos y fumadores con EPOC (p = 0,758). Se encontró una asociación significativa entre el alelo A de HTR2A (rs6311) y la incidencia de EPOC en el modelo predictivo (p = 0,02; 1,80 [1,04-3,11]). En los fumadores, este alelo también se asoció al número de paquetes fumados al año (p = 0,02) y, además, de forma marginal con los valores de FEV1/FVC (p = 0,06). Conclusión: Nuestros resultados apuntan a un posible papel del alelo A de HTR2A (rs6311) en la patogénesis de EPOC, indicando que este efecto dependería en parte del consumo de tabaco a través de una interacción gen-ambiente

Effect of Roux-en-Y gastric surgery on ciprofloxacin pharmacokinetics: an obvious effect?

PURPOSE: To evaluate pharmacokinetic parameters of ciprofloxacin in patients undergoing Roux-en-Y gastric surgery (RYGS). METHODS: Controlled, single-dose, open-label study in patients undergoing RYGS. Healthy overweight/obese patients 18-60 years old were included. The assessment was performed once in control patients and three times in case patients (before surgery and 1 and 6 months after surgery). In each visit, the subjects received a single oral dose of ciprofloxacin 500 mg. Venous blood samples were obtained at baseline and 0.5, 1, 1.25, 1.5, 1.75, 2, 2.5, 3, 4, 8 and 14 h after ciprofloxacin intake. Pre- and post-surgery variables were compared using paired ANOVA or the Wilcoxon tests and control vs cases using ANOVA or Mann Whitney. Given the post-surgery change in body weight, the parameters were corrected by dose (mg)/body weight (kg). The analysis was performed using SPSS. RESULTS: Ciprofloxacin Cmax was significantly reduced 1 month after surgery (1840.9 ± 485.2 vs 1589.6 ± 321.8 ng/ml; p = 0.032) but not 6 months after. Cmax on the sixth month was lower than Cmax in control group (2160.4 ± 408.6 vs 1589.6 ± 321.8 ng/ml; p < 0.001). After correcting by the dose (mg)/patient's body weight, both Cmax and AUClast showed significant decrease 1 and 6 months after surgery: Cmax, 289.1 ± 65.3 and 263.5 ± 52.1 (ng/ml)/(dose (mg)/weight (kg)) respectively vs 429.3 ± 127.6 (ng/ml)/(dose (mg)/weight (kg)) at baseline; AUC, 1340.6 ± 243.0 and 1299.2 ± 415.4 (h × ng/ml)/(dose (mg)/weight (kg)) respectively vs 1896.7 ± 396.8 (h × ng/ml)/(dose (mg)/weight (kg)) at baseline. Cmax 1 month post-surgery showed lower values than the control group (375.4 ± 77.4 vs 263.5 ± 52.1 ng/ml; p < 0.001). CONCLUSION: Ciprofloxacin absorption is impaired 1 month and 6 months after RYGS. The effect on Cmax and AUClast faded on the sixth month due to weight loss. It is no necessary to modify the doses of ciprofloxacin in these patients.

Association of HTR2A-1438G/A Genetic Polymorphism With Smoking and Chronic Obstructive Pulmonary Disease.

INTRODUCTION: Cigarette smoking is a major risk factor in the development of chronic obstructive pulmonary disease (COPD). Serotonin levels have been associated with COPD and smoking has been as a significant modulator. Elevated levels of serotonin are responsible for bronchoconstriction and pulmonary vasoconstriction and also nicotine dependence, thus serotonin response could be affected by genetic polymorphisms in transporters and receptors of serotonin. OBJECTIVES: The aim of the current study was to analyze the effect of SLC6A4 (5HTT_LPR) (rs25531) and HTR2A-1438G/A (rs6311) genetic polymorphisms on the relation between smoking habits and COPD. METHODS: The association between SLC6A4 (5HTT_LPR) (rs25531), HTR2A-1438G/A (rs6311), smoking degree and COPD was analyzed in a total of 77 COPD patients (active smokers) and 90 control subjects (active healthy smokers). The DNA was extracted of peripheral leukocytes samples and genotyping was performed using an allele specific polymerase chain reaction. RESULTS: The distribution of SLC6A4 genotypes did not vary between healthy smokers and COPD patients (P=0.758). On the other hand, the A allele of HTR2A (rs6311) was significantly associated with COPD incidence in the trend model (P=0.02; 1.80 [1.04-3.11]). Among all smokers, this allele was also associated with the number of pack years smoked (P=0.02) and also, we observed a marginal association with FEV1/FVC values (P=0.06). CONCLUSION: Our results point a possible role of the A allele of HTR2A (rs6311) in COPD pathogenesis, suggesting that this effect depends partly on tobacco consumption due to a gene-by-environment interaction.

A Paradox: α-Klotho Levels and Smoking Intensity.

Reports regarding smoking differences in α-klotho expression have provided conflicting results. In the current study we focused on the influence of smoking intensity to serum levels of the aging molecule α-klotho in healthy smokers. 40 middle aged healthy smokers without airway obstruction or restriction were selected for the analysis. Serum levels of soluble α-klotho were significantly higher in heavy smokers (P < 0.001). These results are in agreement with the possibility that α-klotho acts as anti-inflammatory molecule and strengthen the hypothesis that an increase of serum levels of α-klotho might be a compensatory response to smoking stress in healthy population.

Effect of Genetic Polymorphisms and Long-Term Tobacco Exposure on the Risk of Breast Cancer.

INTRODUCTION: Tobacco smoke contains many potentially harmful compounds that may act differently and at different stages in breast cancer development. The focus of this work was to assess the possible role of cigarette smoking (status, dose, duration or age at initiation) and polymorphisms in genes coding for enzymes involved in tobacco carcinogen metabolism (CYP1A1, CYP2A6) or in DNA repair (XRCC1, APEX1, XRCC3 and XPD) in breast cancer development. METHODS: We designed a case control study with 297 patients, 217 histologically verified breast cancers (141 smokers and 76 non-smokers) and 80 healthy smokers in a cohort of Spanish women. RESULTS: We found an association between smoking status and early age at diagnosis of breast cancer. Among smokers, invasive carcinoma subtype incidence increased with intensity and duration of smoking (all Ptrend < 0.05). When smokers were stratified by smoking duration, we only observed differences in long-term smokers, and the CYP1A1 Ile462Ile genotype was associated with increased risk of breast cancer (OR = 7.12 (1.98-25.59)). CONCLUSIONS: Our results support the main effect of CYP1A1 in estrogenic metabolism rather than in tobacco carcinogen activation in breast cancer patients and also confirmed the hypothesis that CYP1A1 Ile462Val, in association with long periods of active smoking, could be a breast cancer risk factor.

The Effect of Polymorphisms in DNA Repair Genes and Carcinogen Metabolizers on Leukocyte Telomere Length: A Cohort of Healthy Spanish Smokers.

INTRODUCTION: Smoking implies exposure to carcinogenic agents that causes DNA damage, which could be suspected to enhance telomere attrition. To protect and deal with DNA damage, cells possess mechanisms that repair and neutralize harmful substances. Polymorphisms altering DNA repair capacity or carcinogen metabolism may lead to synergistic effects with tobacco carcinogen-induced shorter telomere length independently of cancer interaction. The aim of this study was to explore the association between leukocyte telomere length (LTL) and several genetic polymorphisms in DNA repair genes and carcinogen metabolizers in a cohort of healthy smokers. METHODS: We evaluated the effect of six genetic polymorphisms in cytochrome P1A1 (Ile462Val), XRCC1 (Arg399Gln), APEX1 (Asp148Glu), XRCC3 (Thr241Met), and XPD (Asp312Asn; Lys751Gln) on LTL in a cohort of 145 healthy smokers in addition to smoking habits. RESULTS: Logistic regression analysis showed an association between XRCC1 399Gln allele and shorter telomere length (OR = 5.03, 95% CI = 1.08% to 23.36%). There were not association between the rest of polymorphisms analyzed and LTL. CONCLUSIONS: Continuous exposure to tobacco could overwhelm the DNA repair machinery, making the effect of the polymorphisms that reduce repair capacity more pronounced. Analyzing the function of smoking-induced DNA-repair genes and LTL is an important goal in order to identify therapeutic targets to treat smoking-induced diseases.

Are SNP-Smoking Association Studies Needed in Controls? DNA Repair Gene Polymorphisms and Smoking Intensity.

Variations in tobacco-related cancers, incidence and prevalence reflect differences in tobacco consumption in addition to genetic factors. Besides, genes related to lung cancer risk could be related to smoking behavior. Polymorphisms altering DNA repair capacity may lead to synergistic effects with tobacco carcinogen-induced lung cancer risk. Common problems in genetic association studies, such as presence of gene-by-environment (G x E) correlation in the population, may reduce the validity of these designs. The main purpose of this study was to evaluate the independence assumption for selected SNPs and smoking behaviour in a cohort of 320 healthy Spanish smokers. We found an association between the wild type alleles of XRCC3 Thr241Met or KLC3 Lys751Gln and greater smoking intensity (OR = 12.98, 95% CI = 2.86-58.82 and OR=16.90, 95% CI=2.09-142.8; respectively). Although preliminary, the results of our study provide evidence that genetic variations in DNA-repair genes may influence both smoking habits and the development of lung cancer. Population-specific G x E studies should be carried out when genetic and environmental factors interact to cause the disease.

Effects of cigarette smoking and nicotine metabolite ratio on leukocyte telomere length.

Studies of the effects of smoking on leukocyte telomere length (LTL) using cigarettes smoked per day or pack years smoked (PYS) present limitations. Reported high levels of smoking may not increase toxin exposure levels proportionally. Nicotine metabolism ratio (NMR) predicts total cigarette puff volume and overall exposure based on total N-nitrosamines, is highly reproducible and independent of time since the last cigarette. We hypothesized that smokers with higher NMRs will exhibit increased total puff volume, reflecting efforts to extract more nicotine from their cigarettes and increasing toxin exposure. In addition, higher levels of smoking could cause a gross damage in LTL. The urinary cotinine, 3-OH cotinine and nicotine levels of 147 smokers were analyzed using a LC/MS system Triple-Q6410. LTL and CYP2A6 genotype was determined by PCR in blood samples. We found a significant association between NMR and CYP2A6 genotype. Reduction in LTL was seen in relation to accumulated tobacco consumption and years smoking when we adjusted for age and gender. However, there were no significant differences between NMR values and LTL. In our study the higher exposure was associated with lower number of PYS. Smokers with reduced cigarette consumption may exhibit compensatory smoking behavior that results in no reduced tobacco toxin exposure. Our results suggest that lifetime accumulated smoking exposure could cause a gross damage in LTL rather than NMR or PYS. Nevertheless, a combination of smoking topography (NMR) and consumption (PYS) measures may provide useful information about smoking effects on health outcomes.

Relationship between genotypes Sult1a2 and Cyp2d6 and tamoxifen metabolism in breast cancer patients.

Tamoxifen is a pro-drug widely used in breast cancer patients to prevent tumor recurrence. Prior work has revealed a role of cytochrome and sulfotransferase enzymes in tamoxifen metabolism. In this descriptive study, correlations were examined between concentrations of tamoxifen metabolites and genotypes for CYP2D6, CYP3A4, CYP3A5, SULT1A1, SULT1A2 and SULT1E1 in 135 patients with estrogen receptor-positive breast cancer. Patients were genotyped using the Roche-AmpliChip® CYP450 Test, and Real-Time and conventional PCR-RFLP. Plasma tamoxifen, 4-hydroxy-tamoxifen, N-desmethyl-tamoxifen, endoxifen and tamoxifen-N-oxide were isolated and quantified using a high-pressure liquid chromatography-tandem mass spectrometry system. Significantly higher endoxifen levels were detected in patients with the wt/wt CYP2D6 compared to the v/v CYP2D6 genotype (p<0.001). No differences were detected in the remaining tamoxifen metabolites among CYP2D6 genotypes. Patients featuring the SULT1A2*2 and SULT1A2*3 alleles showed significantly higher plasma levels of 4-hydroxy-tamoxifen and endoxifen (p = 0.025 and p = 0.006, respectively), as likely substrates of the SULT1A2 enzyme. Our observations indicate that besides the CYP2D6 genotype leading to tamoxifen conversion to potent hydroxylated metabolites in a manner consistent with a gene-dose effect, SULT1A2 also seems to play a role in maintaining optimal levels of both 4-hydroxy-tamoxifen and endoxifen.

Favorable responses to acute and chronic exercise in McArdle patients.

OBJECTIVE: This study reports acute exercise responses in a large (N = 46) series of patients with McArdle disease and responses to exercise training in a smaller (n = 9) set of patients. DESIGN: Patients were studied during both incremental and steady-state cycle ergometer exercise, using cardiopulmonary testing, and the patients were compared with age- and gender-matched controls. SETTING: The study was performed in a university setting (clinical exercise physiology laboratory). PARTICIPANTS: The 46 patients showed common features of McArdle disease. They were definitively diagnosed by histochemistry, biochemistry, and/or molecular genetic analysis. The 46 controls were healthy, sedentary individuals. INTERVENTION: Nine patients were studied before and after an 8-month supervised aerobic exercise training program (including five weekly sessions of walking and/or cycling exercise with a duration no greater than 60 minutes). MAIN OUTCOME MEASUREMENTS: The main indicators of exercise capacity that we measured were peak power output, peak oxygen uptake (VO2peak), and ventilatory threshold (VT). RESULTS: Exercise capacity (peak power output, 35% control; VO2peak, 44% control; VT, 66% control) was markedly depressed in the patients. The patients who trained improved peak power output (25%), VO2peak (44%), and VT (27%), with no evidence of negative outcomes from training. Although not achieving normal values, the response to training put the patients into the lower limit of normal controls. CONCLUSIONS: Under carefully controlled conditions, patients with McArdle disease may perform acute exercise safely, and they may respond favorably to training. This may offer an additional therapeutic option to help normalize the lifestyles of these patients.