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INTRODUCTION: Heart failure (HF) incidence is increasing in older adults with high hospitalisation and mortality rates. Treatment is complicated by side effects and comorbidities. We investigated the clinical characteristics of octogenarians presenting to the HF clinic. METHODS: Data were collected on octogenarians (80-89 years) referred to the HF clinic in two periods. The data included demographics, HF phenotype, comorbidities, symptoms and treatment. We investigate the temporal changes in clinical characteristics using χ2 test. We aimed to determine the clinical characteristics which were associated with optimisation of HF pharmacological intervention in the clinic, conducting multivariate regression analysis. Statistical significance is determined at p<0.05. RESULTS: Data were collected in April 2012 to January 2014 and in June 2021 to December 2022. In this cross-sectional study of temporal data, 571 octogenarians were referred to the clinic in the latter period, in whom the prevalence of HF was 68.48% (391 patients). HF with preserved ejection fraction (HFpEF) was the most common phenotype and increased significantly compared with the first period (46.3% and 29.2%, p<0.001). Frailty, chronic kidney disease and ischaemic heart disease increased significantly versus the first period (p<0.001). During the second period, and following the consultation, of the patients with HF with reduced ejection fraction (HFrEF), 86.4% and 82.7% were on a beta blocker and on an ACE inhibitor/angiotensin receptor blocker/angiotensin receptor-neprilysin inhibitor, respectively. Clinical characteristics associated with further optimisations of HF pharmacological therapy in the HF clinic were: New York Heart Association (NYHA) functional class III and the presence of HFrEF phenotype CONCLUSIONS: With a prevalence of HF at 68% among the octogenarians referred to the HF clinic, HFpEF incidence is rising. The decision to optimise HF pharmacological treatment in octogenarians is driven by NYHA functional class III and the presence of HFrEF phenotype.
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Insuficiencia Cardíaca , Sistema de Registros , Humanos , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/epidemiología , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/tratamiento farmacológico , Anciano de 80 o más Años , Femenino , Masculino , Estudios Transversales , Prevalencia , Volumen Sistólico/fisiología , Factores de Edad , Incidencia , Comorbilidad , Factores de Riesgo , Función Ventricular Izquierda/fisiologíaRESUMEN
It is estimated that by 2050, 17% of the world's population will be greater than 85 years old, which, combined with cardiovascular disease (CVD) being the leading cause of death and disability, sets an unprecedented burden on our health and care systems. This perfect storm will be accompanied by a rise in the prevalence of CVD due to increased survival of patients with pre-existing CVD and the incidence of CVD that is associated with the process of ageing. In this review, we will focus on the diagnosis and management of common CVD conditions in old age, namely: heart failure (HF), coronary artery disease (CAD), atrial fibrillation (AF) and valvular heart disease (VHD). Despite limited evidence, clinical guidelines are increasingly considering the complexity of management of these conditions in the older person, which often coexist, for example, AF and HF or CAD and VHD. Furthermore, they, in turn, need specific consideration in the context of comorbidities, polypharmacy, frailty and impaired cognition found in this age group. Hence, the emerging role of the geriatric cardiologist is therefore vital in performing comprehensive geriatric assessment, attending multidisciplinary team meetings and ultimately considering the patient and the sum of their diseases in their totality. There have been recent advances in CVD management but how we apply these to deliver integrated care to the elderly population is key. This review article aims to bring together emerging studies and guidelines on assessment and management of CVD in the elderly, summarising latest definitions, diagnostics, therapeutics and future challenges.
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Enfermedades Cardiovasculares , Humanos , Anciano , Enfermedades Cardiovasculares/terapia , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/diagnóstico , Evaluación Geriátrica/métodos , Geriatría , Anciano de 80 o más Años , Cardiología/tendencias , Comorbilidad , EnvejecimientoRESUMEN
AIMS/HYPOTHESIS: Lipoprotein-associated phospholipase A2 (Lp-PLA2) activity has an independent prognostic association with major coronary events (MCE). However, no study has investigated whether type 2 diabetes status modifies the effect of Lp-PLA2 activity or inhibition on the risk of MCE. We investigate the interaction between diabetes status and Lp-PLA2 activity with risk of MCE. Subsequently, we test the resulting hypothesis that diabetes status will play a role in modifying the efficacy of an Lp-PLA2 inhibitor. METHODS: A retrospective cohort study design was utilised in two study populations. Discovery analyses were performed in the Genetics of Diabetes Audit and Research in Tayside Scotland (GoDARTS) cohort based in Scotland, UK. Participants were categorised by type 2 diabetes control status: poorly controlled (HbA1c ≥ 48 mmol/mol or ≥6.5%) and well-controlled (HbA1c < 48 mmol/mol or <6.5%) diabetes (n = 7420). In a secondary analysis of the Stabilization of Atherosclerotic Plaque by Initiation of Darapladib Therapy (STABILITY) trial of Lp-PLA2 inhibitor (darapladib) efficacy, 15,828 participants were stratified post hoc by type 2 diabetes diagnosis status (diabetes or no diabetes) at time of recruitment. Lp-PLA2 activity was then divided into population-specific quartiles. MCE were determined from linked medical records in GoDARTS and trial records in STABILITY. First, the interaction between diabetes control status and Lp-PLA2 activity on the outcome of MCE was explored in GoDARTS. The effect was replicated in the placebo arm of STABILITY. The effect of Lp-PLA2 on MCE was then examined in models stratified by diabetes status. This helped determine participants at higher risk. Finally, the effect of Lp-PLA2 inhibition was assessed in STABILITY in the higher risk group. Cox proportional hazards models adjusted for confounders were used to assess associations. RESULTS: In GoDARTS, a significant interaction between increased Lp-PLA2 activity (continuous and quartile divided) and diabetes control status was observed in the prediction of MCE (p < 0.0001). These effects were replicated in the placebo arm of STABILITY (p < 0.0001). In GoDARTS, stratified analyses showed that, among individuals with poorly controlled diabetes, the hazards of MCE for those with high (Q4) Lp-PLA2 activity was 1.19 compared with individuals with lower (Q1-3) Lp-PLA2 activity (95% CI 1.11, 1.38; p < 0.0001) and 1.35 (95% CI 1.16, 1.57; p < 0.0001) when compared with those with the lowest activity (Q1). Those in the higher risk group were identified as individuals with the highest Lp-PLA2 activity (Q4) and poorly controlled diabetes or diabetes. Based on these observations in untreated populations, we hypothesised that the Lp-PLA2 inhibitor would have more benefit in this higher risk group. In this risk group, Lp-PLA2 inhibitor use was associated with a 33% reduction in MCE compared with placebo (HR 0.67 [95% CI 0.50, 0.90]; p = 0.008). In contrast, Lp-PLA2 inhibitor showed no efficacy in individuals with low activity, regardless of diabetes status, or among those with no baseline diabetes and high Lp-PLA2 activity. CONCLUSIONS/INTERPRETATION: These results support the hypothesis that diabetes status modifies the association between Lp-PLA2 activity and MCE. These results suggest that cardiovascular morbidity and mortality associated with Lp-PLA2 activity is especially important in patients with type 2 diabetes, particularly those with worse glycaemic control. Further investigation of the effects of Lp-PLA2 inhibition in diabetes appears warranted. DATA AVAILABILITY: STABILITY trial data are available from clinicaltrials.gov repository through the GlaxoSmithKline clinical study register https://clinicaltrials.gov/ct2/show/NCT00799903 . GoDARTS datasets generated during and/or analysed during the current study are available following request to the GoDARTS Access Managements Group https://godarts.org/scientific-community/ .
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1-Alquil-2-acetilglicerofosfocolina Esterasa , Diabetes Mellitus Tipo 2 , Biomarcadores , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Humanos , Pronóstico , Estudios Retrospectivos , Factores de RiesgoRESUMEN
Leukotrienes play a central pathophysiological role in both paediatric and adult asthma. However, 35% to 78% of asthmatics do not respond to leukotriene inhibitors. In this study we tested the role of the LTA4H regulatory variant rs2660845 and age of asthma onset in response to montelukast in ethnically diverse populations. We identified and genotyped 3,594 asthma patients treated with montelukast (2,514 late-onset and 1,080 early-onset) from seven cohorts (UKBiobank, GoSHARE, BREATHE, Tayside RCT, PAGES, GALA II and SAGE). Individuals under montelukast treatment experiencing at least one exacerbation in a 12-month period were compared against individuals with no exacerbation, using logistic regression for each cohort and meta-analysis. While no significant association was found with European late-onset subjects, a meta-analysis of 523 early-onset individuals from European ancestry demonstrated the odds of experiencing asthma exacerbations by carriers of at least one G allele, despite montelukast treatment, were increased (odds-ratio = 2.92, 95%confidence interval (CI): 1.04-8.18, I2 = 62%, p = 0.0412) compared to those in the AA group. When meta-analysing with other ethnic groups, no significant increased risk of asthma exacerbations was found (OR = 1.60, 95% CI: 0.61-4.19, I2 = 85%, p = 0.342). Our study demonstrates that genetic variation in LTA4H, together with timing of asthma onset, may contribute to variability in montelukast response. European individuals with early-onset (≤18y) carrying at least one copy of rs2660845 have increased odd of exacerbation under montelukast treatment, presumably due to the up-regulation of LTA4H activity. These findings support a precision medicine approach for the treatment of asthma with montelukast.
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Acetatos/uso terapéutico , Asma/tratamiento farmacológico , Ciclopropanos/uso terapéutico , Epóxido Hidrolasas/genética , Farmacogenética , Quinolinas/uso terapéutico , Sulfuros/uso terapéutico , Adolescente , Adulto , Edad de Inicio , Alelos , Antiasmáticos/uso terapéutico , Asma/fisiopatología , Niño , Preescolar , Estudios Transversales , Europa (Continente) , Femenino , Genotipo , Hospitalización , Humanos , Antagonistas de Leucotrieno/uso terapéutico , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Análisis de Regresión , Riesgo , Adulto JovenRESUMEN
Angioedema occurring in the head and neck region is a rare and sometimes life-threatening adverse reaction to angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs). Few studies have investigated the association of common variants with this extreme reaction, but none have explored the combined influence of rare variants yet. Adjudicated cases of ACEI-induced angioedema (ACEI-AE) or ARB-induced angioedema (ARB-AE) and controls were recruited at five different centers. Sequencing of 1,066 samples (408 ACEI-AE, ARB-AE, and 658 controls) was performed using exome-enriched sequence data. A common variant of the F5 gene that causes an increase in blood clotting (rs6025, p.Arg506Gln, also called factor V Leiden), was significantly associated with both ACEI-AE and ARB-AE (odds ratio: 2.85, 95% confidence interval (CI), 1.89-4.25). A burden test analysis of five rare missense variants in F5 was also found to be associated with ACEI-AE or ARB-AE, P = 2.09 × 10-3 . A combined gene risk score of these variants, and the common variants rs6025 and rs6020, showed that individuals carrying at least one variant had 2.21 (95% CI, 1.49-3.27, P = 6.30 × 10-9 ) times the odds of having ACEI-AE or ARB-AE. The increased risk due to the common Leiden allele was confirmed in a genome-wide association study from the United States. A high risk of angioedema was also observed for the rs6020 variant that is the main coagulation defect-causing variant in black African and Asian populations. We found that deleterious missense variants in F5 are associated with an increased risk of ACEI-AE or ARB-AE.
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Angioedema/inducido químicamente , Angioedema/genética , Antagonistas de Receptores de Angiotensina/efectos adversos , Inhibidores de la Enzima Convertidora de Angiotensina/efectos adversos , Análisis Mutacional de ADN , Secuenciación del Exoma , Factor V/genética , Mutación Missense , Anciano , Angioedema/etnología , Estudios de Casos y Controles , Europa (Continente)/epidemiología , Exoma , Femenino , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Persona de Mediana Edad , Tasa de Mutación , Medición de Riesgo , Factores de Riesgo , Estados Unidos/epidemiologíaRESUMEN
Regulator of G-protein signaling 4 (RGS4) is a potent modulator of G-protein-coupled receptor signal transduction that is expressed throughout the pain matrix. Here, we use genetic mouse models to demonstrate a role of RGS4 in the maintenance of chronic pain states in male and female mice. Using paradigms of peripheral inflammation and nerve injury, we show that the prevention of RGS4 action leads to recovery from mechanical and cold allodynia and increases the motivation for wheel running. Similarly, RGS4KO eliminates the duration of nocifensive behavior in the second phase of the formalin assay. Using the Complete Freud's Adjuvant (CFA) model of hindpaw inflammation we also demonstrate that downregulation of RGS4 in the adult ventral posterolateral thalamic nuclei promotes recovery from mechanical and cold allodynia. RNA sequencing analysis of thalamus (THL) from RGS4WT and RGS4KO mice points to many signal transduction modulators and transcription factors that are uniquely regulated in CFA-treated RGS4WT cohorts. Ingenuity pathway analysis suggests that several components of glutamatergic signaling are differentially affected by CFA treatment between RGS4WT and RGS4KO groups. Notably, Western blot analysis shows increased expression of metabotropic glutamate receptor 2 in THL synaptosomes of RGS4KO mice at time points at which they recover from mechanical allodynia. Overall, our study provides information on a novel intracellular pathway that contributes to the maintenance of chronic pain states and points to RGS4 as a potential therapeutic target.SIGNIFICANCE STATEMENT There is an imminent need for safe and efficient chronic pain medications. Regulator of G-protein signaling 4 (RGS4) is a multifunctional signal transduction protein, widely expressed in the pain matrix. Here, we demonstrate that RGS4 plays a prominent role in the maintenance of chronic pain symptoms in male and female mice. Using genetically modified mice, we show a dynamic role of RGS4 in recovery from symptoms of sensory hypersensitivity deriving from hindpaw inflammation or hindlimb nerve injury. We also demonstrate an important role of RGS4 actions in gene expression patterns induced by chronic pain states in the mouse thalamus. Our findings provide novel insight into mechanisms associated with the maintenance of chronic pain states and demonstrate that interventions in RGS4 activity promote recovery from sensory hypersensitivity symptoms.
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Dolor Crónico/metabolismo , Hiperalgesia/metabolismo , Proteínas RGS/metabolismo , Núcleos Talámicos/metabolismo , Animales , Dolor Crónico/genética , Regulación hacia Abajo , Femenino , Hiperalgesia/genética , Masculino , Ratones , Ratones Noqueados , Dimensión del Dolor , Proteínas RGS/genética , Factores Sexuales , Transducción de Señal/fisiologíaRESUMEN
OBJECTIVE: Progression to insulin therapy in clinically diagnosed type 2 diabetes is highly variable. GAD65 autoantibodies (GADA) are associated with faster progression, but their predictive value is limited. We aimed to determine if a type 1 diabetes genetic risk score (T1D GRS) could predict rapid progression to insulin treatment over and above GADA testing. RESEARCH DESIGN AND METHODS: We examined the relationship between T1D GRS, GADA (negative or positive), and rapid insulin requirement (within 5 years) using Kaplan-Meier survival analysis and Cox regression in 8,608 participants with clinical type 2 diabetes (onset >35 years and treated without insulin for ≥6 months). T1D GRS was both analyzed continuously (as standardized scores) and categorized based on previously reported centiles of a population with type 1 diabetes (<5th [low], 5th-50th [medium], and >50th [high]). RESULTS: In GADA-positive participants (3.3%), those with higher T1D GRS progressed to insulin more quickly: probability of insulin requirement at 5 years (95% CI): 47.9% (35.0%, 62.78%) (high T1D GRS) vs. 27.6% (20.5%, 36.5%) (medium T1D GRS) vs. 17.6% (11.2%, 27.2%) (low T1D GRS); P = 0.001. In contrast, T1D GRS did not predict rapid insulin requirement in GADA-negative participants (P = 0.4). In Cox regression analysis with adjustment for age of diagnosis, BMI, and cohort, T1D GRS was independently associated with time to insulin only in the presence of GADA: hazard ratio per SD increase was 1.48 (1.15, 1.90); P = 0.002. CONCLUSIONS: A T1D GRS alters the clinical implications of a positive GADA test in patients with clinical type 2 diabetes and is independent of and additive to clinical features.
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Autoanticuerpos/sangre , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Glutamato Descarboxilasa/inmunología , Insulina/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Autoanticuerpos/genética , Estudios de Cohortes , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/inmunología , Progresión de la Enfermedad , Femenino , Predisposición Genética a la Enfermedad , Glutamato Descarboxilasa/genética , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Proyectos de Investigación , Factores de Riesgo , Análisis de SupervivenciaRESUMEN
AIMS/HYPOTHESIS: The aim of the study was to examine the association between lipoprotein-associated phospholipase A2 (Lp-PLA2) activity levels and incident diabetic retinopathy and change in retinopathy grade. METHODS: This was a cohort study of diabetic participants with serum collected at baseline and routinely collected diabetic retinal screening data. Participants with type 2 diabetes from the GoDARTS (Genetics of Diabetes Audit and Research in Tayside Scotland) cohort were used. This cohort is composed of individuals of white Scottish ancestry from the Tayside region of Scotland. Survival analysis accounting for informative censoring by modelling death as a competing risk was performed for the development of incident diabetic retinopathy from a disease-free state in a 3 year follow-up period (n = 1364) by stratified Lp-PLA2 activity levels (in quartiles). The same analysis was performed for transitions to more severe grades. RESULTS: The hazard of developing incident diabetic retinopathy was 2.08 times higher (95% CI 1.64, 2.63) for the highest quartile of Lp-PLA2 activity compared with the lowest. Higher Lp-PLA2 activity levels were associated with a significantly increased risk for transitions to all grades. The hazards of developing observable (or more severe) and referable (or more severe) retinopathy were 2.82 (95% CI 1.71, 4.65) and 1.87 (95% CI 1.26, 2.77) times higher for the highest quartile of Lp-PLA2 activity compared with the lowest, respectively. CONCLUSIONS/INTERPRETATION: Higher Lp-PLA2 levels are associated with increased risk of death and the development of incident diabetic retinopathy, as well as transitions to more severe grades of diabetic retinopathy. These associations are independent of calculated LDL-cholesterol and other traditional risk factors. Further, this biomarker study shows that the association is temporally sensitive to the proximity of the event to measurement of Lp-PLA2.
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1-Alquil-2-acetilglicerofosfocolina Esterasa/sangre , Diabetes Mellitus Tipo 2/sangre , Retinopatía Diabética/sangre , Anciano , Biomarcadores/sangre , Diabetes Mellitus Tipo 2/complicaciones , Retinopatía Diabética/diagnóstico , Progresión de la Enfermedad , Registros Electrónicos de Salud , Femenino , Humanos , Estudios Longitudinales , Masculino , Microcirculación , Persona de Mediana Edad , Factores de Riesgo , Escocia , Resultado del TratamientoAsunto(s)
Diabetes Mellitus Tipo 2/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Incidencia , Estimación de Kaplan-Meier , Estilo de Vida , Masculino , Persona de Mediana Edad , Escocia/epidemiología , Autoinforme , Adulto JovenRESUMEN
Aims: A genetic variant in LILRB5 (leukocyte immunoglobulin-like receptor subfamily-B) (rs12975366: T > C: Asp247Gly) has been reported to be associated with lower creatine phosphokinase (CK) and lactate dehydrogenase (LDH) levels. Both biomarkers are released from injured muscle tissue, making this variant a potential candidate for susceptibility to muscle-related symptoms. We examined the association of this variant with statin intolerance ascertained from electronic medical records in the GoDARTS study. Methods and results: In the GoDARTS cohort, the LILRB5 Asp247 variant was associated with statin intolerance (SI) phenotypes; one defined as having raised CK and being non-adherent to therapy [odds ratio (OR) 1.81; 95% confidence interval (CI): 1.34-2.45] and the other as being intolerant to the lowest approved dose of a statin before being switched to two or more other statins (OR 1.36; 95% CI: 1.07-1.73). Those homozygous for Asp247 had increased odds of developing both definitions of intolerance. Importantly the second definition did not rely on CK elevations. These results were replicated in adjudicated cases of statin-induced myopathy in the PREDICTION-ADR consortium (OR1.48; 95% CI: 1.05-2.10) and for the development of myalgia in the JUPITER randomized clinical trial of rosuvastatin (OR1.35, 95% CI: 1.10-1.68). A meta-analysis across the studies showed a consistent association between Asp247Gly and outcomes associated with SI (OR1.34; 95% CI: 1.16-1.54). Conclusion: This study presents a novel immunogenetic factor associated with statin intolerance, an important risk factor for cardiovascular outcomes. The results suggest that true statin-induced myalgia and non-specific myalgia are distinct, with a potential role for the immune system in their development. We identify a genetic group that is more likely to be intolerant to their statins.
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Antígenos CD/genética , Tolerancia a Medicamentos , Dislipidemias/tratamiento farmacológico , Mutación Missense , Mialgia/inducido químicamente , Receptores Inmunológicos/genética , Rosuvastatina Cálcica/efectos adversos , Antígenos CD/metabolismo , Biomarcadores/sangre , Creatina Quinasa/sangre , ADN/genética , Análisis Mutacional de ADN , Dislipidemias/sangre , Femenino , Genotipo , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , L-Lactato Deshidrogenasa/sangre , Masculino , Persona de Mediana Edad , Mialgia/diagnóstico , Mialgia/genética , Fenotipo , Receptores Inmunológicos/metabolismo , Rosuvastatina Cálcica/uso terapéuticoRESUMEN
BACKGROUND: To test the association of a recently reported variant in the creatine kinase (CK) muscle gene, CKM Glu83Gly (rs11559024) with constitutive creatine phosphokinase (CK) levels, CK variation, and inducibility. Given the diagnostic importance of CK in determining muscle damage, we tested the association of the variant with myalgia. METHODS AND RESULTS: Meta-analysis between longitudinal cohort GoDARTS (Genetics of Diabetes Audit and Research, Tayside Scotland), minor allele frequency (=0.02), and randomized clinical trial (JUPITER [Justification for the Use of Statins in Primary Prevention: An Intervention Trial Evaluating Rosuvastatin], minor allele frequency=0.018) was used to replicate the association with baseline CK measures. GoDARTS was used to study the relationship with CK variability. Myalgia was studied in JUPITER trial participants. Baseline and SDs of CK were on average 18% (P value=6×10-63) and 24% (P value=2×10-5) lower for carriers of the variant, respectively. The variant was not associated with myalgia (odds ratio, 0.84; 95% confidence interval, 0.52-1.38). CONCLUSIONS: This study highlights that a genetic factor known to be associated with constitutive CK levels is also associated with CK variability and inducibility. This is discussed in the context of evidence to suggest that the variant has an impact on inducibility of CK by trauma through a previously reported case of a homozygous carrier. However, the lack of association between the variant and myalgia suggests that it cannot reliably be used as a biomarker for muscle symptoms.
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Creatina Quinasa/genética , Diabetes Mellitus Tipo 2/genética , Variación Genética , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Creatina Quinasa/metabolismo , Diabetes Mellitus Tipo 2/patología , Femenino , Frecuencia de los Genes , Genotipo , Homocigoto , Humanos , Hiperlipidemias/prevención & control , Masculino , Persona de Mediana Edad , Mialgia/genética , Mialgia/patología , Oportunidad Relativa , Polimorfismo de Nucleótido Simple , Rosuvastatina Cálcica/uso terapéuticoRESUMEN
Regulator of G-protein signaling 9-2 (RGS9-2) is a striatal-enriched signal-transduction modulator known to have a critical role in the development of addiction-related behaviors following exposure to psychostimulants or opioids. RGS9-2 controls the function of several G-protein-coupled receptors, including dopamine receptor and mu opioid receptor (MOR). We previously showed that RGS9-2 complexes negatively control morphine analgesia, and promote the development of morphine tolerance. In contrast, RGS9-2 positively modulates the actions of other opioid analgesics, such as fentanyl and methadone. Here we investigate the role of RGS9-2 in regulating responses to oxycodone, an MOR agonist prescribed for the treatment of severe pain conditions that has addictive properties. Using mice lacking the Rgs9 gene (RGS9KO), we demonstrate that RGS9-2 positively regulates the rewarding effects of oxycodone in pain-free states, and in a model of neuropathic pain. Furthermore, although RGS9-2 does not affect the analgesic efficacy of oxycodone or the expression of physical withdrawal, it opposes the development of oxycodone tolerance, in both acute pain and chronic neuropathic pain models. Taken together, these data provide new information on the signal-transduction mechanisms that modulate the rewarding and analgesic actions of oxycodone.
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Analgésicos Opioides/uso terapéutico , Dolor Crónico/tratamiento farmacológico , Dolor Crónico/metabolismo , Oxicodona/uso terapéutico , Dimensión del Dolor/métodos , Proteínas RGS/deficiencia , Analgésicos Opioides/farmacología , Animales , Relación Dosis-Respuesta a Droga , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Oxicodona/farmacología , Dimensión del Dolor/efectos de los fármacos , Resultado del TratamientoRESUMEN
OBJECTIVE: Thiazolidinediones (TZDs) are putatively transported into the liver by OATP1B1 (encoded by SLCO1B1) and metabolized by CYP450 2C8 enzyme (encoded by CYP2C8). While CYP2C8*3 has been shown to alter TZD pharmacokinetics, it has not been shown to alter efficacy. RESEARCH DESIGN AND METHODS: We genotyped 833 Scottish patients with type 2 diabetes treated with pioglitazone or rosiglitazone and jointly investigated association of variants in these two genes with therapeutic outcome. RESULTS: The CYP2C8*3 variant was associated with reduced glycemic response to rosiglitazone (P = 0.01) and less weight gain (P = 0.02). The SLCO1B1 521T>C variant was associated with enhanced glycemic response to rosiglitazone (P = 0.04). The super responders defined by combined genotypes at CYP2C8 and SLCO1B1 had a 0.39% (4 mmol/mol) greater HbA1c reduction (P = 0.006) than the poor responders. Neither of the variants had a significant impact on pioglitazone response. CONCLUSIONS: These results show that variants in CYP2C8 and SLCO1B1 have a large clinical impact on the therapeutic response to rosiglitazone and highlight the importance of studying transporter and metabolizing genes together in pharmacogenetics.