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1.
Artigo em Inglês | MEDLINE | ID: mdl-38693445

RESUMO

PURPOSE: This study focused on the selected markers of oxidative stress, impact of elevated lead levels on long-term hearing quality. We investigated whether the presence of certain essential minerals might provide protection to the auditory system against the effects of lead (and cadmium) compounds. METHODS: The research group included 280 male employees of the zinc and lead smelter, which was divided into: L-Pb-low blood lead concentration (PbB) subgroup, H-Pb-high PbB subgroup. Hearing tests were performed using the click evoked otoacoustic emission (CEOAE). RESULTS: Zinc protoporphyrin level was significantly higher in the H-Pb subgroup by 68%. Cd concentration was significantly higher in H-Pb by 33%. The Ca concentration was significantly lower in the H-Pb by - 2%. Selected oxidative stress markers concentration were significantly higher in the H-Pb group: malondialdehyde (MDA) by 4%, and lipofuscin (LPS) by 9%. In the CEOAE results showed statistically significant differences between the L-Pb and H-Pb subgroups. Larger negative changes in otoemission amplitude were observed in H-Pb subgroup. All otoemission results showed a statistically significant negative correlation with age, time of work, MDA concentration, and with PbB. Selected CEOAE parameters showed a significant negative correlation with cadmium blood concentration (CdB), and a positive correlation with Ca and Zn. CONCLUSION: Elevated blood lead content in occupational exposure is associated with an increase in MDA and LPS concentration, which negatively correlates with CEOAE parameters. This suggests an important role of oxidative stress in the long-term deterioration of hearing.

2.
Int J Mol Sci ; 25(11)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38892242

RESUMO

Skeletal muscle atrophy (SMA) is caused by a rise in muscle breakdown and a decline in protein synthesis, with a consequent loss of mass and function. This study characterized the effect of an amino acid mixture (AA) in models of SMA, focusing on mitochondria. C57/Bl6 mice underwent immobilization of one hindlimb (I) or cardiotoxin-induced muscle injury (C) and were compared with controls (CTRL). Mice were then administered AA in drinking water for 10 days and compared to a placebo group. With respect to CTRL, I and C reduced running time and distance, along with grip strength; however, the reduction was prevented by AA. Tibialis anterior (TA) muscles were used for histology and mitochondria isolation. I and C resulted in TA atrophy, characterized by a reduction in both wet weight and TA/body weight ratio and smaller myofibers than those of CTRL. Interestingly, these alterations were lightly observed in mice treated with AA. The mitochondrial yield from the TA of I and C mice was lower than that of CTRL but not in AA-treated mice. AA also preserved mitochondrial bioenergetics in TA muscle from I and C mice. To conclude, this study demonstrates that AA prevents loss of muscle mass and function in SMA by protecting mitochondria.


Assuntos
Aminoácidos , Metabolismo Energético , Camundongos Endogâmicos C57BL , Músculo Esquelético , Atrofia Muscular , Animais , Camundongos , Metabolismo Energético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Aminoácidos/farmacologia , Aminoácidos/metabolismo , Atrofia Muscular/metabolismo , Atrofia Muscular/tratamento farmacológico , Atrofia Muscular/patologia , Atrofia Muscular/etiologia , Masculino , Modelos Animais de Doenças , Mitocôndrias Musculares/metabolismo , Mitocôndrias Musculares/efeitos dos fármacos , Mitocôndrias Musculares/patologia , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos
3.
FASEB J ; 36(12): e22650, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36394523

RESUMO

Hepatitis C virus (HCV) adopts several immune evasion mechanisms such as interfering with innate immunity or promoting T-cell exhaustion. However, the recent direct-antiviral agents (DAAs) rapidly eliminate the virus, and the repercussions in terms of immune system balance are unknown. Here we compared the PBMCs transcriptomic profile of patients with HCV chronic infection at baseline (T0) and 12 weeks after the end of the therapy (SVR12) with DAAs. 3862 genes were differently modulated, identifying oxidative phosphorylation as the top canonical pathway differentially activated. Therefore, we dissected PBMCs bioenergetic profile by analyzing mitochondrial respiration and glycolysis at 4 timepoints: T0, 4 weeks of therapy, end of therapy (EoT), and SVR12. Maximal and reserve respiratory capacity considerably increased at EoT, persisting until SVR12. Notably, over time a significant increase was observed in respiratory chain (RC) complexes protein levels and the enzymatic activity of complexes I, II, and IV. Mitochondrial-DNA integrity improved over time, and the expression of mitochondrial biogenesis key regulators such as TFAM, Nrf-1, and PPARGC1A significantly increased at SVR12; hence, RC complexes synthesis and mitochondrial respiration were supported after treatment. HCV clearance with DAAS profoundly changed PBMCs bioenergetic profile, suggesting the immunometabolism study as a new approach to the understanding of viral immune evasion mechanisms and host adaptations during infections and therapies.


Assuntos
Hepacivirus , Hepatite C , Humanos , Antivirais/farmacologia , Antivirais/uso terapêutico , Leucócitos Mononucleares , Hepatite C/tratamento farmacológico , Homeostase , Mitocôndrias
4.
Int J Mol Sci ; 25(1)2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38203581

RESUMO

Hepatic fibrosis is a complex process that develops in chronic liver diseases. Even though the initiation and progression of fibrosis rely on the underlying etiology, mutual mechanisms can be recognized and targeted for therapeutic purposes. Irrespective of the primary cause of liver disease, persistent damage to parenchymal cells triggers the overproduction of reactive species, with the consequent disruption of redox balance. Reactive species are important mediators for the homeostasis of both hepatocytes and non-parenchymal liver cells. Indeed, other than acting as cytotoxic agents, reactive species are able to modulate specific signaling pathways that may be relevant to hepatic fibrogenesis. After a brief introduction to redox biology and the mechanisms of fibrogenesis, this review aims to summarize the current evidence of the involvement of redox-dependent pathways in liver fibrosis and focuses on possible therapeutic targets.


Assuntos
Cognição , Cirrose Hepática , Humanos , Oxirredução , Biologia
5.
Int J Mol Sci ; 24(10)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37240168

RESUMO

Luteolin (3',4',5,7-tetrahydroxyflavone), a member of the flavonoid family derived from plants and fruits, shows a wide range of biomedical applications. In fact, due to its anti-inflammatory, antioxidant and immunomodulatory activities, Asian medicine has been using luteolin for centuries to treat several human diseases, including arthritis, rheumatism, hypertension, neurodegenerative disorders and various infections. Of note, luteolin displays many anti-cancer/anti-metastatic properties. Thus, the purpose of this review consists in highlighting the relevant mechanisms by which luteolin inhibits tumor progression in metastasis, i.e., affecting epithelial-mesenchymal transition (EMT), repressing angiogenesis and lysis of extracellular matrix (ECM), as well as inducing apoptosis.


Assuntos
Luteolina , Neoplasias , Humanos , Luteolina/farmacologia , Luteolina/uso terapêutico , Transição Epitelial-Mesenquimal , Neoplasias/metabolismo , Flavonoides/farmacologia , Apoptose , Linhagem Celular Tumoral
6.
Int J Mol Sci ; 24(3)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36768260

RESUMO

Redox homeostasis is determinant in the modulation of quiescence/self-renewal/differentiation of stem cell lines. The aim of this study consisted of defining the impact of redox modifications on cell fate in a human hepatic progenitor line. To achieve this, the HepaRG cell line, which shows oval ductular bipotent characteristics, was used. The impact of redox status on the balance between self-renewal and differentiation of HepaRG cells was investigated using different methodological approaches. A bioinformatic analysis initially proved that the trans-differentiation of HepaRG toward bipotent progenitors is associated with changes in redox metabolism. We then exposed confluent HepaRG (intermediate differentiation phase) to oxidized (H2O2) or reduced (N-acetylcysteine) extracellular environments, observing that oxidation promotes the acquisition of a mature HepaRG phenotype, while a reduced culture medium stimulates de-differentiation. These results were finally confirmed through pharmacological modulation of the nuclear factor (erythroid-derived 2)-like 2 (NRF2), a principal modulator of the antioxidant response, in confluent HepaRG. NRF2 inhibition led to intracellular pro-oxidative status and HepaRG differentiation, while its activation was associated with low levels of reactive species and de-differentiation. In conclusion, this study shows that both intra- and extracellular redox balance are crucial in the determination of HepaRG fate. The impact of redox status in the differentiation potential of HepaRG cells is significant on the utilization of this cell line in pre-clinical studies.


Assuntos
Peróxido de Hidrogênio , Fator 2 Relacionado a NF-E2 , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Peróxido de Hidrogênio/metabolismo , Fígado/metabolismo , Linhagem Celular , Células-Tronco/metabolismo , Diferenciação Celular/fisiologia , Oxirredução , Hepatócitos/metabolismo
7.
Br J Clin Pharmacol ; 88(2): 846-852, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34265100

RESUMO

This analysis aimed to describe the pharmacokinetics (PK) of acalabrutinib and its active metabolite, ACP-5862. A total of 8935 acalabrutinib samples from 712 subjects and 2394 ACP-5862 samples from 304 subjects from 12 clinical studies in patients with B-cell malignancies and healthy subjects were analysed by nonlinear mixed-effects modelling. Acalabrutinib PK was characterized by a 2-compartment model with first-order elimination. The large variability in absorption was adequately described by transit compartment chain and first-order absorption, with between-occasion variability on the mean transit time and relative bioavailability. The PK of ACP-5862 was characterized by a 2-compartment model with first-order elimination, and the formation rate was defined as the acalabrutinib clearance multiplied by the fraction metabolized. Health status, Eastern Cooperative Oncology Group performance status, and coadministration of proton-pump inhibitors were significant covariates. However, none of the investigated covariates led to clinically meaningful changes in exposure, supporting a flat dosing of acalabrutinib.


Assuntos
Benzamidas , Neoplasias , Benzamidas/farmacocinética , Voluntários Saudáveis , Humanos , Modelos Biológicos , Pirazinas/farmacocinética
8.
Br J Clin Pharmacol ; 88(7): 3211-3221, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35072287

RESUMO

AIMS: Filgotinib is a potent, oral, JAK1-preferential inhibitor for the treatment of rheumatoid arthritis (RA). This report describes exposure-response (ER) analyses of filgotinib for dose confirmation based on three phase 3 and two phase 2 studies in moderate to severe RA patients. METHODS: The pharmacokinetic exposures used in ER analyses were derived from population pharmacokinetic analysis. The exposure-efficacy relationships were assessed for efficacy endpoints (ACR20/50/70 and DAS28) over effective area under curve (AUCeff ), the combined exposures of filgotinib and GS-829845 (major, active metabolite), with nonlinear logistic regression models developed. Also, a t-test was performed to compare the exposure between subjects who achieved response and those who did not. For the ER analyses of safety, exposures were examined between subjects who experienced and who did not experience the evaluated safety events, which was conducted separately for filgotinib and GS-829845. RESULTS: The nonlinear logistic regression showed increasing response with increasing exposure, with exposures at 200 mg dose primarily residing on the curve plateau. Also, AUCeff was significantly higher in the subjects who achieved responses compared to those who did not (10 900 vs 9900 h*ng/mL for ACR20, P value < .0001). For exposure-safety analyses, filgotinib and GS-829845 exposures were similar irrespective of the presence/absence of the evaluated safety endpoints, indicating no exposure-safety relationship for common treatment-emergent adverse events (TEAEs)/laboratory abnormalities and serious TEAEs/infections. CONCLUSIONS: ER analyses confirmed that filgotinib produced more robust therapeutic effects across the exposure range observed at 200 mg once daily compared to lower doses, and collectively with the lack of exposure-safety relationship, the 200 mg once daily dose was supported for commercialization.


Assuntos
Artrite Reumatoide , Piridinas , Triazóis , Antirreumáticos/efeitos adversos , Artrite Reumatoide/tratamento farmacológico , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Humanos , Inibidores de Janus Quinases/efeitos adversos , Piridinas/efeitos adversos , Resultado do Tratamento , Triazóis/efeitos adversos
9.
Int J Mol Sci ; 23(21)2022 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-36361558

RESUMO

This study attempts to determine whether the increased blood lead concentration affects the posturographic test and to determine the relationship between the parameters of posture stability and selected parameters of oxidative stress. The study population consisted of 268 male employees and was divided into two equal subgroups, depending on the lead content in the blood. A posturographic examination was performed. Concentrations of lead, cadmium, zinc protoporphyrin, selected essential elements, and selected markers of oxidative stress in the blood were tested. Higher blood lead concentrations positively affected the values of the sway results: the field and the mean velocity of the center of the feet pressure in posturography. The absolute value of the proprioception ratio was similar in both subgroups. The content of malondialdehyde shows a statistically significantly higher value in a subgroup with high blood lead concentration and exhibits significant correlations only with some of the posturography parameters. The lipofuscin content in erythrocytes correlates with the results of the posturography test. Zinc protoporphyrin, total oxidant status, total antioxidant capacity, selected minerals, and metals did not correlate with the results of the posturography test. In conclusion, posturographic results correlate only with selected markers of oxidative stress, so it can be assumed that the effect on the body balance is only partial.


Assuntos
Chumbo , Postura , Humanos , Masculino , Propriocepção , Estresse Oxidativo , Eritrócitos
10.
Int J Mol Sci ; 22(7)2021 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-33916835

RESUMO

The disturbance of protein O-GlcNAcylation is emerging as a possible link between altered brain metabolism and the progression of neurodegeneration. As observed in brains with Alzheimer's disease (AD), flaws of the cerebral glucose uptake translate into reduced protein O-GlcNAcylation, which promote the formation of pathological hallmarks. A high-fat diet (HFD) is known to foster metabolic dysregulation and insulin resistance in the brain and such effects have been associated with the reduction of cognitive performances. Remarkably, a significant role in HFD-related cognitive decline might be played by aberrant protein O-GlcNAcylation by triggering the development of AD signature and mitochondrial impairment. Our data support the impairment of total protein O-GlcNAcylation profile both in the brain of mice subjected to a 6-week high-fat-diet (HFD) and in our in vitro transposition on SH-SY5Y cells. The reduction of protein O-GlcNAcylation was associated with the development of insulin resistance, induced by overfeeding (i.e., defective insulin signaling and reduced mitochondrial activity), which promoted the dysregulation of the hexosamine biosynthetic pathway (HBP) flux, through the AMPK-driven reduction of GFAT1 activation. Further, we observed that a HFD induced the selective impairment of O-GlcNAcylated-tau and of O-GlcNAcylated-Complex I subunit NDUFB8, thus resulting in tau toxicity and reduced respiratory chain functionality respectively, highlighting the involvement of this posttranslational modification in the neurodegenerative process.


Assuntos
Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Dieta Hiperlipídica/efeitos adversos , Mitocôndrias/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Acilação , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/patologia , Animais , Encéfalo/patologia , Linhagem Celular Tumoral , Masculino , Camundongos , Mitocôndrias/patologia
11.
Int J Mol Sci ; 21(11)2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32481481

RESUMO

Iron deficiency (ID) is the most frequent nutritional deficiency in the whole population worldwide, and the second most common cause of anemia in the elderly. The prevalence of anemia is expecting to rise shortly, because of an ageing population. Even though WHO criteria define anemia as a hemoglobin serum concentration <12 g/dL in women and <13 g/dL in men, several authors propose different and specific cut-off values for the elderly. Anemia in aged subjects impacts health and quality of life, and it is associated with several negative outcomes, such as longer time of hospitalization and a higher risk of disability. Furthermore, it is an independent risk factor of increased morbidity and mortality. Even though iron deficiency anemia is a common disorder in older adults, it should be not considered as a normal ageing consequence, but a sign of underlying dysfunction. Relating to the molecular mechanism in Iron Deficiency Anemia (IDA), hepcidin has a key role in iron homeostasis. It downregulates the iron exporter ferroportin, inhibiting both iron absorption and release. IDA is frequently dependent on blood loss, especially caused by gastrointestinal lesions. Thus, a diagnostic algorithm for IDA should include invasive investigation such as endoscopic procedures. The treatment choice is influenced by the severity of anemia, underlying conditions, comorbidities, and the clinical state of the patient. Correction of anemia and iron supplementation should be associated with the treatment of the causal disease.


Assuntos
Anemia Ferropriva/etiologia , Anemia Ferropriva/terapia , Ferro/administração & dosagem , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Algoritmos , Pessoas com Deficiência , Feminino , Hemoglobinas/análise , Hepcidinas/fisiologia , Humanos , Infusões Parenterais , Ferro/farmacocinética , Deficiências de Ferro , Masculino , Ciências da Nutrição , Prevalência , Qualidade de Vida , Fatores de Risco
12.
Aging Clin Exp Res ; 31(5): 727-732, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30132205

RESUMO

AIM: Aging is associated with increased inflammation, particularly in frailty. Indeed, such patient presents increased serum inflammatory markers, such as C-reactive protein and interleukin-6. Interleukin-6 is an important stimulating factor for the production of procalcitonin. The aim of this study is to evaluate the diagnostic reliability of serum PCT in the diagnosis of sepsis in frail elderly patients. METHODS: Using Fried's criteria for frailty, 140 older patients hospitalized for any cause were consecutively enrolled and divided in two groups: no-frail (60 patients) and frail (80 patients). Patients were further categorized on the basis of the presence/absence of sepsis. Interleukin-6, procalcitonin and inflammatory indices were sampled at hospital admission. RESULTS: Septic patients from frail and no-frail groups showed higher values of interleukin-6 and procalcitonin. However, focusing on groups without sepsis, a statistically significant difference of interleukin-6 and procalcitonin values among frail and no-frail groups was seen at the post-hoc analysis. In frail group, procalcitonin cut-off of 0.5 ng/ml had a sensibility and specificity, respectively, of 100 and 22%. Through receiver operating characteristic curve (ROC) analysis, we found that procalcitonin serum value of 1.4 ng/ml had better sensibility and specificity (respectively, 93.8 and 84.4%, AUC 0.965). CONCLUSIONS: In our study, we confirm the diagnostic reliability of procalcitonin in frail elderly patients for the diagnosis of sepsis. We found that 1.4 ng/ml was the best cut-off in this population.


Assuntos
Pró-Calcitonina/sangue , Sepse/sangue , Sepse/diagnóstico , Idoso , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Estudos de Casos e Controles , Feminino , Fragilidade/complicações , Humanos , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Reprodutibilidade dos Testes , Sepse/complicações
13.
Toxicol Appl Pharmacol ; 320: 51-59, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28213092

RESUMO

Increased incidence of C-cell carcinogenicity has been observed for glucagon-like-protein-1 receptor (GLP-1r) agonists in rodents. It is suggested that the duration of exposure is an indicator of carcinogenic potential in rodents of the different products on the market. Furthermore, the role of GLP-1-related mechanisms in the induction of C-cell carcinogenicity has gained increased attention by regulatory agencies. This study proposes an integrative pharmacokinetic/pharmacodynamic (PKPD) framework to identify explanatory factors and characterize differences in carcinogenic potential of the GLP-1r agonist products. PK models for four products (exenatide QW (once weekly), exenatide BID (twice daily), liraglutide and lixisenatide) were developed using nonlinear mixed effects modelling. Predicted exposure was subsequently linked to GLP-1r stimulation using in vitro GLP-1r potency data. A logistic regression model was then applied to exenatide QW and liraglutide data to assess the relationship between GLP-1r stimulation and thyroid C-cell hyperplasia incidence as pre-neoplastic predictor of a carcinogenic response. The model showed a significant association between predicted GLP-1r stimulation and C-cell hyperplasia after 2years of treatment. The predictive performance of the model was evaluated using lixisenatide, for which hyperplasia data were accurately described during the validation step. The use of a model-based approach provided insight into the relationship between C-cell hyperplasia and GLP-1r stimulation for all four products, which is not possible with traditional data analysis methods. It can be concluded that both pharmacokinetics (exposure) and pharmacodynamics (potency for GLP-1r) factors determine C-cell hyperplasia incidence in rodents. Our work highlights the pharmacological basis for GLP-1r agonist-induced C-cell carcinogenicity. The concept is promising for application to other drug classes.


Assuntos
Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Liraglutida/toxicidade , Peptídeos/toxicidade , Neoplasias da Glândula Tireoide/induzido quimicamente , Peçonhas/toxicidade , Animais , Bases de Dados Factuais/tendências , Esquema de Medicação , Exenatida , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/toxicidade , Liraglutida/administração & dosagem , Dinâmica não Linear , Peptídeos/administração & dosagem , Valor Preditivo dos Testes , Roedores , Neoplasias da Glândula Tireoide/patologia , Peçonhas/administração & dosagem
14.
Br J Clin Pharmacol ; 83(3): 593-602, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27641003

RESUMO

AIMS: Despite long clinical experience with deferiprone, there is limited information on its pharmacokinetics in children aged <6 years. Here we assess the impact of developmental growth on the pharmacokinetics of deferiprone in this population using a population approach. Based on pharmacokinetic bridging concepts, we also evaluate whether the recommended doses yield appropriate systemic exposure in this group of patients. METHODS: Data from a study in which 18 paediatric patients were enrolled were available for the purposes of this analysis. Patients were randomised to three deferiprone dose levels (8.3, 16.7 and 33.3 mg kg-1 ). Blood samples were collected according to an optimised sampling scheme in which each patient contributed to a maximum of five samples. A population pharmacokinetic model was developed using NONMEM v.7.2. Model selection criteria were based on graphical and statistical summaries. RESULTS: A one-compartment model with first-order absorption and first-order elimination best described the pharmacokinetics of deferiprone. Drug disposition parameters were affected by body weight, with both clearance and volume increasing allometrically with size. Simulation scenarios show that comparable systemic exposure (AUC) is achieved in children and adults after similar dose levels in mg kg-1 , with median (5-95th quantiles) AUC values, respectively, of 340.6 (223.2-520.0) µmol l-1  h and 318.5 (200.4-499.0) µmol l-1  h at 75 mg kg-1 day-1 , and 453.7 (297.3-693.0) µmol l-1  h and 424.2 (266.9-664.0) µmol l-1  h at 100 mg kg-1  day-1 given as three times daily (t.i.d.) doses. CONCLUSIONS: Based on the current findings, a dosing regimen of 25 mg kg-1  t.i.d. is recommended in children aged <6 years, with the possibility of titration up to 33.3 mg kg-1  t.i.d.


Assuntos
Piridonas/administração & dosagem , Piridonas/farmacocinética , Pré-Escolar , Simulação por Computador , Deferiprona , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Humanos , Lactente , Quelantes de Ferro/farmacocinética , Masculino , Modelos Biológicos , Piridonas/sangue , Método Simples-Cego
15.
Pharm Res ; 33(2): 498-509, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26555666

RESUMO

PURPOSE: Here we show how a model-based approach may be used to provide further insight into the role of clinical and demographic covariates on the progression of iron overload. The therapeutic effect of deferoxamine is used to illustrate the application of disease modelling as a means to characterising treatment response in individual patients. METHODS: Serum ferritin, demographic characteristics and individual treatment data from clinical routine practice on 27 patients affected by ß-thalassaemia major were used for the purposes of this analysis. The time course of serum ferritin was described by a hierarchical nonlinear mixed effects model, in which compliance was parameterised as a covariate factor. Modelling and simulation procedures were implemented in NONMEM (7.2.0). RESULTS: A turnover model best described serum ferritin changes over time, with the effect of blood transfusions introduced on the ferritin conversion rate and the effect of deferoxamine on the elimination parameter (Kout) in a proportional manner. The results of the simulations showed that poor quality of execution is preferable over drug holidays; and that independently of the compliance pattern, the therapeutic intervention is not effective if >60% of the doses are missed. CONCLUSIONS: Modelling of ferritin response enables characterisation of the dynamics of iron overload due to chronic transfusion. The approach can be used to support decision making in clinical practice, including personalisation of the dose for existing and novel chelating agents.


Assuntos
Terapia por Quelação/métodos , Desferroxamina/uso terapêutico , Ferritinas/sangue , Sobrecarga de Ferro/tratamento farmacológico , Sideróforos/uso terapêutico , Talassemia beta/terapia , Adolescente , Adulto , Criança , Simulação por Computador , Desferroxamina/sangue , Desferroxamina/farmacologia , Relação Dose-Resposta a Droga , Transfusão de Eritrócitos/efeitos adversos , Humanos , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/etiologia , Modelos Biológicos , Sideróforos/sangue , Sideróforos/farmacologia , Adulto Jovem , Talassemia beta/sangue , Talassemia beta/complicações
17.
Br J Clin Pharmacol ; 80(5): 979-91, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25940398

RESUMO

AIM: Despite the continuous endeavour to achieve high standards in medical care through effectiveness measures, a quantitative framework for the assessment of the benefit-risk balance of new medicines is lacking prior to regulatory approval. The aim of this short review is to summarise the approaches currently available for benefit-risk assessment. In addition, we propose the use of pharmacokinetic-pharmacodynamic (PKPD) modelling as the pharmacological basis for evidence synthesis and evaluation of novel therapeutic agents. METHODS: A comprehensive literature search has been performed using MESH terms in PubMed, in which articles describing benefit-risk assessment and modelling and simulation were identified. In parallel, a critical review of multi-criteria decision analysis (MCDA) is presented as a tool for characterising a drug's safety and efficacy profile. RESULTS: A definition of benefits and risks has been proposed by the European Medicines Agency (EMA), in which qualitative and quantitative elements are included. However, in spite of the value of MCDA as a quantitative method, decisions about benefit-risk balance continue to rely on subjective expert opinion. By contrast, a model-informed approach offers the opportunity for a more comprehensive evaluation of benefit-risk balance before extensive evidence is generated in clinical practice. CONCLUSIONS: Benefit-risk balance should be an integral part of the risk management plan and as such considered before marketing authorisation. Modelling and simulation can be incorporated into MCDA to support the evidence synthesis as well evidence generation taking into account the underlying correlations between favourable and unfavourable effects. In addition, it represents a valuable tool for the optimization of protocol design in effectiveness trials.


Assuntos
Aprovação de Drogas/métodos , Drogas em Investigação/farmacocinética , Medição de Risco/métodos , Técnicas de Apoio para a Decisão , Humanos , Modelos Biológicos
18.
Biochim Biophys Acta ; 1832(12): 2019-26, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23851051

RESUMO

Cholestasis is one of the major causes of liver diseases. A chronic accumulation of toxic bile acids in the liver, which occurs in this condition, can induce fibrosis and cirrhosis. Inflammation is a fundamental component of acute and chronic cholestatic liver injury. Platelet-activating factor (PAF) is a proinflammatory lipid which may be generated by two independent pathways called the de novo and remodeling pathway being the last responsible for the synthesis of PAF during inflammation. In recent years a key role in PAF remodeling has been attributed to lysophosphatidylcholine acyltransferase (LPCAT) enzymes. Although the knowledge on their characteristic is growing, the exact mechanism of LPCAT in pathological conditions remains still unknown. Here, we reported that the level of lyso-PAF and PAF significantly increased in the liver of cirrhotic vs. control rats together with a significant decrease in both mRNA abundance and protein level of both LPCAT1 and LPCAT2. Acyltransferase activities of both LPCAT1 and LPCAT2 were parallel decreased in the liver of cirrhotic animals. Interestingly, treatment with silybin strongly decreased the level of both pro-inflammatory lipids and restored the activity and expression of both LPCAT1 and LPCAT2 of cirrhotic liver. Silybin effect was specific for LPCAT1 and LPCAT2 since it did not affect LPCAT3 mRNA abundance of cirrhotic liver.


Assuntos
1-Acilglicerofosfocolina O-Aciltransferase/antagonistas & inibidores , Cromatografia em Camada Fina , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/prevenção & controle , Cirrose Hepática/complicações , Fator de Ativação de Plaquetas/metabolismo , Silimarina/farmacologia , 1-Acilglicerofosfocolina O-Aciltransferase/genética , 1-Acilglicerofosfocolina O-Aciltransferase/metabolismo , Animais , Antioxidantes/farmacologia , Western Blotting , Regulação para Baixo , Inflamação/etiologia , Inflamação/metabolismo , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Fosfolipases A2/metabolismo , Fator de Ativação de Plaquetas/genética , RNA Mensageiro/genética , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Silibina
19.
Br J Clin Pharmacol ; 78(6): 1397-406, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25052529

RESUMO

AIMS: To characterize the pharmacokinetics of deferiprone in healthy subjects using a model-based approach and to assess the effect of demographic and physiological factors on drug exposure. METHODS: Data from 55 adult healthy subjects receiving deferiprone (solution 100 mg ml(-1)) were used for model building purposes. A population pharmacokinetic analysis was performed using nonmem v.7.2. The contribution of gender, age, weight and creatinine clearance (CLcr) on drug disposition was evaluated according to standard forward inclusion, backward deletion procedures. Model selection criteria were based on graphical and statistical summaries. RESULTS: A one compartment model with first order oral absorption was found to describe best the pharmacokinetics of deferiprone. Simulated exposure values were comparable with previously published data. Mean AUC estimates were 45.8 and 137.4 mg l(-1) h, whereas Cmax increased from 17.6 to 26.5 mg l(-1) after administration of 25 and 75 mg kg(-1) doses, respectively. Gender differences in the apparent volume of distribution (20%) have been identified, which are unlikely to be of clinical relevance. Furthermore, simulation scenarios reveal that dose adjustment is required for patients with reduced CLcr . Doses of 60, 40 and 25 mg kg(-1) for patients showing mild, moderate and severe renal impairment are proposed based on CLcr values of 60-89, 30-59 and 15-29 ml min(-1), respectively. CONCLUSIONS: Our analysis has enabled the assessment of the impact of gender and CLcr on the pharmacokinetics of deferiprone. Moreover, it provides the basis for dosing recommendations in renal impairment. The implication of these covariates on systemic exposure is currently not available in the prescribing information of deferiprone.


Assuntos
Piridonas/farmacocinética , Adulto , Área Sob a Curva , Creatinina/sangue , Deferiprona , Feminino , Humanos , Masculino , Taxa de Depuração Metabólica , Modelos Biológicos , Piridonas/administração & dosagem , Insuficiência Renal/metabolismo , Caracteres Sexuais
20.
Nutrients ; 16(9)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38732604

RESUMO

BACKGROUND: Among elderly inpatients, malnutrition is one of the most important predictive factors affecting length of stay (LOS), mortality, and risk of re-hospitalization. METHODS: We conducted an observational, retrospective study on a cohort of 2206 acutely inpatients. Serum albumin and lymphocytes were evaluated. Instant Nutritional Assessment (INA) and the Prognostic Nutritional Index (PNI) were calculated to predict in-hospital mortality, LOS, and risk of rehospitalization. RESULTS: An inverse relationship between LOS, serum albumin, and PNI were found. Deceased patients had lower albumin levels, lower PNI values, and third- and fourth-degree INA scores. An accurate predictor of mortality was PNI (AUC = 0.785) after ROC curve analysis; both lower PNI values (HR = 3.56) and third- and fourth-degree INA scores (HR = 3.12) could be independent risk factors for mortality during hospitalization after Cox regression analysis. Moreover, among 309 subjects with a lower PNI value or third- and fourth-class INA, hospitalization was re-hospitalization. CONCLUSIONS: PNI and INA are two simple and quick-to-calculate tools that can help in classifying the condition of hospitalized elderly patients also based on their nutritional status, or in assessing their mortality risk. A poor nutritional status at the time of discharge may represent an important risk factor for rehospitalization in the following thirty days. This study confirms the importance of evaluating nutritional status at the time of hospitalization, especially in older patients. This study also confirms the importance for adequate training of doctors and nurses regarding the importance of maintaining a good nutritional status as an integral part of the therapeutic process of hospitalization in acute departments.


Assuntos
Avaliação Geriátrica , Mortalidade Hospitalar , Pacientes Internados , Tempo de Internação , Desnutrição , Avaliação Nutricional , Estado Nutricional , Humanos , Idoso , Masculino , Feminino , Estudos Retrospectivos , Idoso de 80 Anos ou mais , Tempo de Internação/estatística & dados numéricos , Avaliação Geriátrica/métodos , Prognóstico , Desnutrição/diagnóstico , Desnutrição/mortalidade , Pacientes Internados/estatística & dados numéricos , Readmissão do Paciente/estatística & dados numéricos , Fatores de Risco , Hospitalização/estatística & dados numéricos , Albumina Sérica/análise
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